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Burns EA, Wilson JJ, Mathur S, Kieser R, Gong Z, Hu CCA, Tang CHA, Petkova J, Yuen C, Mai H, Shah S, Rice L, Ganguly S, Pingali SR. Long-term outcomes in patients with Burkitt lymphoma older than 65 years: an analysis of the Texas Cancer Registry. Ann Hematol 2023; 102:2753-2763. [PMID: 37422592 DOI: 10.1007/s00277-023-05328-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 06/19/2023] [Indexed: 07/10/2023]
Abstract
Burkitt lymphoma (BL) is an extremely aggressive but curable subtype of non-Hodgkin lymphoma. While younger patients have excellent outcomes in response to aggressive chemoimmunotherapy, the rarity of this disease in older patients and limitations caused by age, comorbidities, and performance status may negate survival advantages. This analysis assessed outcomes of older adults with BL through data provided by the Texas Cancer Registry (TCR). Patients ≥65 years with BL were assessed. Patients were dichotomized into 1997-2007 and 2008-2018. Median overall survival (OS) and disease-specific survival (DSS) were assessed using Kaplan-Meier methodology, and covariates including age, race, sex, stage, primary site, and poverty index were analyzed using Pearson Chi-squared analysis. Odds ratio (OR) with 95% confidence intervals (CI) was used to assess factors contributing to patients not offered systemic therapy. P value <0.05 was considered statistically significant. Non-BL mortality events were also categorized. There were 325 adults, 167 in 1997-2007 and 158 in 2008-2018; 106 (63.5%) and 121 (76.6%) received systemic therapy, a trend that increased with time (p = 0.010). Median OS for 1997-2007 and 2008-2018 was 5 months (95% CI 2.469, 7.531) and 9 months (95% CI 0.000, 19.154) (p = 0.013), and DSS was 72 months (95% CI 56.397, 87.603) (p = 0.604) and not reached, respectively. For patients that received systemic therapy, median OS was 8 months (95% CI 1.278, 14.722) and 26 months (95% CI 5.824, 46.176) (p = 0.072), respectively, and DSS was 79 months (95% CI: 56.416, 101.584) and not reached, respectively (p = 0.607). Age ≥75 years (HR 1.39 [95% CI 1.078, 1.791], p = 0.011) and non-Hispanic whites (HR 1.407 [95% CI 1.024, 1.935], p = 0.035) had poorer outcomes, and patients at the 20-100% poverty index (OR 0.387 [95% CI 0.163, 0.921], p = 0.032) and increasing age at diagnosis (OR 0.947 [95% CI 0.913, 0.983], p = 0.004) were less likely to receive systemic therapy. Of 259 (79.7%) deaths, 62 (23.9%) were non-BL deaths, and 6 (9.6%) of these were from a second cancer. This two-decade analysis of older Texas patients with BL indicates a significant improvement in OS over time. Although patients were more likely to receive systemic therapy over time, treatment disparities existed in patients residing in poverty-stricken regions of Texas and in advancing age. These statewide findings reflect an unmet national need to find a systemic therapeutic strategy that can be tolerated by and augment outcomes in the growing elderly population.
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Affiliation(s)
- Ethan A Burns
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Justin J Wilson
- Trinity School of Medicine, 925 Woodstock Road, Ste 200, GA, Roswell, USA
| | - Sunil Mathur
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Ryan Kieser
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Zimu Gong
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Chih-Chi Andrew Hu
- Center for Translational Research in Hematologic Malignancies, Neal Cancer Center, Houston Methodist Research Institute, 6550 Fannin St, Houston, TX, 77030, USA
| | - Chih-Hang Anthony Tang
- Center for Translational Research in Hematologic Malignancies, Neal Cancer Center, Houston Methodist Research Institute, 6550 Fannin St, Houston, TX, 77030, USA
| | - Jenny Petkova
- Department of Academic Medicine, Houston Methodist Hospital, 6550 Fannin St Ste. 1001, Houston, TX, 77030, USA
| | - Carrie Yuen
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Hanh Mai
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Shilpan Shah
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Lawrence Rice
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
- Department of Academic Medicine, Houston Methodist Hospital, 6550 Fannin St Ste. 1001, Houston, TX, 77030, USA
| | - Siddhartha Ganguly
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA
| | - Sai Ravi Pingali
- Neal Cancer Center, Houston Methodist Hospital, 6445 Main Street, Outpatient Center, 24th Floor., Houston, TX, 77030, USA.
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2
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Ji Y, Luo Y, Wu Y, Sun Y, Zhao L, Xue Z, Sun M, Wei X, He Z, Wu SA, Lin LL, Lu Y, Chang L, Chen F, Chen S, Qian W, Xu X, Chen S, Pan D, Zhou Z, Xia S, Hu CCA, Liang T, Qi L. SEL1L-HRD1 endoplasmic reticulum-associated degradation controls STING-mediated innate immunity by limiting the size of the activable STING pool. Nat Cell Biol 2023; 25:726-739. [PMID: 37142791 PMCID: PMC10185471 DOI: 10.1038/s41556-023-01138-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 03/17/2023] [Indexed: 05/06/2023]
Abstract
Stimulator of interferon genes (STING) orchestrates the production of proinflammatory cytokines in response to cytosolic double-stranded DNA; however, the pathophysiological significance and molecular mechanism underlying the folding and maturation of nascent STING protein at the endoplasmic reticulum (ER) remain unknown. Here we report that the SEL1L-HRD1 protein complex-the most conserved branch of ER-associated degradation (ERAD)-is a negative regulator of the STING innate immunity by ubiquitinating and targeting nascent STING protein for proteasomal degradation in the basal state. SEL1L or HRD1 deficiency in macrophages specifically amplifies STING signalling and immunity against viral infection and tumour growth. Mechanistically, nascent STING protein is a bona fide substrate of SEL1L-HRD1 in the basal state, uncoupled from ER stress or its sensor inositol-requiring enzyme 1α. Hence, our study not only establishes a key role of SEL1L-HRD1 ERAD in innate immunity by limiting the size of the activable STING pool, but identifies a regulatory mechanism and therapeutic approach to targeting STING.
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Affiliation(s)
- Yewei Ji
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA.
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Yuan Luo
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yating Wu
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yao Sun
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lianfeng Zhao
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhen Xue
- Graduate Program in Nutrition, Cornell University, Ithaca, NY, USA
| | - Mengqi Sun
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaoqiong Wei
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Zinan He
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Shuangcheng Alivia Wu
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Liangguang Leo Lin
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - You Lu
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Lei Chang
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Fei Chen
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Siyu Chen
- Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, China
| | - Wei Qian
- Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Xiaoxi Xu
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Shengnuo Chen
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Dongli Pan
- Department of Medical Microbiology and Parasitology, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhangsen Zhou
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
- Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, Shanghai, China
| | - Sheng Xia
- Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Chih-Chi Andrew Hu
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX, USA
| | - Tingbo Liang
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ling Qi
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA.
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA.
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
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3
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Lee AC, Pingali SR, Pinilla-Ibarz JA, Atchison ML, Koumenis C, Argon Y, Thomas-Tikhonenko A, De Trez C, Hu CCA, Tang CHA. Loss of AID exacerbates the malignant progression of CLL. Leukemia 2022; 36:2430-2442. [PMID: 36042317 PMCID: PMC9522595 DOI: 10.1038/s41375-022-01663-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 07/17/2022] [Accepted: 07/20/2022] [Indexed: 01/16/2023]
Abstract
Activation-induced cytidine deaminase (AID) has been implicated as both a positive and a negative factor in the progression of B cell chronic lymphocytic leukemia (CLL), but the role that it plays in the development and progression of this disease is still unclear. We generated an AID knockout CLL mouse model, AID-/-/Eμ-TCL1, and found that these mice die significantly earlier than their AID-proficient counterparts. AID-deficient CLL cells exhibit a higher ER stress response compared to Eμ-TCL1 controls, particularly through activation of the IRE1/XBP1s pathway. The increased production of secretory IgM in AID-deficient CLL cells contributes to their elevated expression levels of XBP1s, while secretory IgM-deficient CLL cells express less XBP1s. This increase in XBP1s in turn leads AID-deficient CLL cells to exhibit higher levels of B cell receptor signaling, supporting leukemic growth and survival. Further, AID-/-/Eμ-TCL1 CLL cells downregulate the tumor suppressive SMAD1/S1PR2 pathway and have altered homing to non-lymphoid organs. Notably, CLL cells from patients with IgHV-unmutated disease express higher levels of XBP1s mRNA compared to those from patients with IgHV-mutated CLL. Our studies thus reveal novel mechanisms by which the loss of AID leads to worsened CLL and may explain why unmutated CLL is more aggressive than mutated CLL.
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Affiliation(s)
- Avery C Lee
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX, USA
- Cell & Molecular Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sai Ravi Pingali
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX, USA
| | - Javier A Pinilla-Ibarz
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, USA
| | - Michael L Atchison
- Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Constantinos Koumenis
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yair Argon
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Cell Pathology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Andrei Thomas-Tikhonenko
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Cancer Pathobiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Carl De Trez
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Chih-Chi Andrew Hu
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX, USA.
| | - Chih-Hang Anthony Tang
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX, USA.
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4
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Mogre S, Blazanin N, Walsh H, Ibinson J, Minnich C, Andrew Hu CC, Glick AB. TGFβ1 regulates HRas-mediated activation of IRE1α through the PERK-RPAP2 axis in keratinocytes. Mol Carcinog 2022; 61:958-971. [PMID: 35975910 PMCID: PMC9486931 DOI: 10.1002/mc.23453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/25/2022] [Accepted: 06/08/2022] [Indexed: 11/08/2022]
Abstract
Transforming Growth Factor β1 (TGFβ1) is a critical regulator of tumor progression in response to HRas. Recently, TGFβ1 has been shown to trigger ER stress in many disease models; however, its role in oncogene-induced ER stress is unclear. Oncogenic HRas induces the unfolded protein response (UPR) predominantly via the Inositol-requiring enzyme 1α (IRE1α) pathway to initiate the adaptative responses to ER stress, with importance for both proliferation and senescence. Here, we show a role of the UPR sensor proteins IRE1α and (PKR)-like endoplasmic reticulum kinase (PERK) to mediate the tumor-suppressive roles of TGFβ1 in mouse keratinocytes expressing mutant forms of HRas. TGFβ1 suppressed IRE1α phosphorylation and activation by HRas both in in vitro and in vivo models while simultaneously activating the PERK pathway. However, the increase in ER stress indicated an uncoupling of ER stress and IRE1α activation by TGFβ1. Pharmacological and genetic approaches demonstrated that TGFβ1-dependent dephosphorylation of IRE1α was mediated by PERK through RNA Polymerase II Associated Protein 2 (RPAP2), a PERK-dependent IRE1α phosphatase. In addition, TGFβ1-mediated growth arrest in oncogenic HRas keratinocytes was partially dependent on PERK-induced IRE1α dephosphorylation and inactivation. Together, these results demonstrate a critical cross-talk between UPR proteins that is important for TGFβ1-mediated tumor suppressive responses.
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Affiliation(s)
- Saie Mogre
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, Pennsylvania, USA
| | - Nicholas Blazanin
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, Pennsylvania, USA
| | - Hailey Walsh
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, Pennsylvania, USA
| | - Jack Ibinson
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, Pennsylvania, USA
| | - Chase Minnich
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, Pennsylvania, USA
| | - Chih-Chi Andrew Hu
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, Texas, USA
| | - Adam B Glick
- Department of Veterinary and Biomedical Sciences, Pennsylvania State University, Pennsylvania, USA
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5
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Shao A, Xu Q, Kang CW, Cain CF, Lee AC, Tang CHA, Del Valle JR, Hu CCA. IRE-1-Targeting Caged Prodrug with Endoplasmic Reticulum Stress-Inducing and XBP-1S-Inhibiting Activities for Cancer Therapy. Mol Pharm 2022; 19:1059-1067. [PMID: 35253431 PMCID: PMC9296017 DOI: 10.1021/acs.molpharmaceut.1c00639] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Activation
of the IRE-1/XBP-1s pathway supports tumor progression.
Here, we report a novel prodrug, TC-D-F07, in which a thiol-reactive
dinitrobenzenesulfonyl (Dns) cage was installed onto the C8 hydroxyl
of the covalent IRE-1 inhibitor D-F07. The electron-withdrawing Dns
group in TC-D-F07 stabilizes the neighboring 1,3-dioxane acetal, allowing
for stimulus-mediated control of its inhibitory activity. TC-D-F07
exhibits high sensitivity to intracellular thiols. Because tumor cells
exhibit higher concentrations of glutathione and cysteine, treatment
with TC-D-F07 results in more sustained levels of D-F07 in transformed
versus normal cells. In addition, we show that a dinitrophenyl cysteine
adduct resulting from cleavage of the Dns group induces endoplasmic
reticulum (ER) stress, causing tumor cells to increase the expression
of XBP-1s. The accumulated levels of D-F07 and its gradual decomposition
into the active IRE-1 inhibitor eventually deprive tumor cells of
XBP-1s, leading to more severe apoptosis than those treated with its
uncaged analogue.
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Affiliation(s)
- Andong Shao
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Qin Xu
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Chang Won Kang
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Christopher F. Cain
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Avery C. Lee
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Chih-Hang Anthony Tang
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Juan R. Del Valle
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Chih-Chi Andrew Hu
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, Texas 77030, United States
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6
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Choi HJ, Tang CHA, Tian L, Wu Y, Sofi MH, Ticer T, Schutt SD, Hu CCA, Yu XZ. XBP-1s Promotes B Cell Pathogenicity in Chronic GVHD by Restraining the Activity of Regulated IRE-1α-Dependent Decay. Front Immunol 2021; 12:705484. [PMID: 34659198 PMCID: PMC8517405 DOI: 10.3389/fimmu.2021.705484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/15/2021] [Indexed: 11/20/2022] Open
Abstract
Allogeneic hematopoietic cell transplantation (allo-HCT) is an effective therapeutic procedure to treat hematological malignancies. However, the benefit of allo-HCT is limited by a major complication, chronic graft-versus-host disease (cGVHD). Since transmembrane and secretory proteins are generated and modified in the endoplasmic reticulum (ER), the ER stress response is of great importance to secretory cells including B cells. By using conditional knock-out (KO) of XBP-1, IRE-1α or both specifically on B cells, we demonstrated that the IRE-1α/XBP-1 pathway, one of the major ER stress response mediators, plays a critical role in B cell pathogenicity on the induction of cGVHD in murine models of allo-HCT. Endoribonuclease activity of IRE-1α activates XBP-1 signaling by converting unspliced XBP-1 (XBP-1u) mRNA into spliced XBP-1 (XBP-1s) mRNA but also cleaves other ER-associated mRNAs through regulated IRE-1α-dependent decay (RIDD). Further, ablation of XBP-1s production leads to unleashed activation of RIDD. Therefore, we hypothesized that RIDD plays an important role in B cells during cGVHD development. In this study, we found that the reduced pathogenicity of XBP-1 deficient B cells in cGVHD was reversed by RIDD restriction in IRE-1α kinase domain KO mice. Restraining RIDD activity per se in B cells resulted in an increased severity of cGVHD. Besides, inhibition of RIDD activity compromised B cell differentiation and led to dysregulated expression of MHC II and costimulatory molecules such as CD86, CD40, and ICOSL in B cells. Furthermore, restraining the RIDD activity without affecting XBP-1 splicing increased B cell ability to induce cGVHD after allo-HCT. These results suggest that RIDD is an important mediator for reducing cGVHD pathogenesis through targeting XBP-1s.
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Affiliation(s)
- Hee-Jin Choi
- Microbiology & Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Chih-Hang Anthony Tang
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX, United States
| | - Linlu Tian
- Microbiology & Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Yongxia Wu
- Microbiology & Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - M Hanief Sofi
- Microbiology & Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Taylor Ticer
- Microbiology & Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Steven D Schutt
- Microbiology & Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Chih-Chi Andrew Hu
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX, United States
| | - Xue-Zhong Yu
- Microbiology & Immunology, Medical University of South Carolina, Charleston, SC, United States.,Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States
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7
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Zundell JA, Fukumoto T, Lin J, Fatkhudinov N, Nacarelli T, Kossenkov AV, Liu Q, Cassel J, Hu CCA, Wu S, Zhang R. Targeting the IRE1α/XBP1 Endoplasmic Reticulum Stress Response Pathway in ARID1A-Mutant Ovarian Cancers. Cancer Res 2021; 81:5325-5335. [PMID: 34548333 DOI: 10.1158/0008-5472.can-21-1545] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 07/22/2021] [Accepted: 08/26/2021] [Indexed: 11/16/2022]
Abstract
The SWI/SNF chromatin-remodeling complex is frequently altered in human cancers. For example, the SWI/SNF component ARID1A is mutated in more than 50% of ovarian clear cell carcinomas (OCCC), for which effective treatments are lacking. Here, we report that ARID1A transcriptionally represses the IRE1α-XBP1 axis of the endoplasmic reticulum (ER) stress response, which confers sensitivity to inhibition of the IRE1α-XBP1 pathway in ARID1A-mutant OCCC. ARID1A mutational status correlated with response to inhibition of the IRE1α-XBP1 pathway. In a conditional Arid1aflox/flox/Pik3caH1047R genetic mouse model, Xbp1 knockout significantly improved survival of mice bearing OCCCs. Furthermore, the IRE1α inhibitor B-I09 suppressed the growth of ARID1A-inactivated OCCCs in vivo in orthotopic xenograft, patient-derived xenograft, and the genetic mouse models. Finally, B-I09 synergized with inhibition of HDAC6, a known regulator of the ER stress response, in suppressing the growth of ARID1A-inactivated OCCCs. These studies define the IRE1α-XBP1 axis of the ER stress response as a targetable vulnerability for ARID1A-mutant OCCCs, revealing a promising therapeutic approach for treating ARID1A-mutant ovarian cancers. SIGNIFICANCE: These findings indicate that pharmacological inhibition of the IRE1α-XBP1 pathway alone or in combination with HDAC6 inhibition represents an urgently needed therapeutic strategy for ARID1A-mutant ovarian cancers.
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Affiliation(s)
- Joseph A Zundell
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania.,Department of Biological Sciences, Misher College of Arts and Sciences, University of Science, Philadelphia, Pennsylvania
| | - Takeshi Fukumoto
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania
| | - Jianhuang Lin
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania
| | - Nail Fatkhudinov
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania
| | - Timothy Nacarelli
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania
| | - Andrew V Kossenkov
- Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, Pennsylvania
| | - Qin Liu
- Molecular and Cellular Oncogenesis Program, The Wistar Institute, Philadelphia, Pennsylvania
| | - Joel Cassel
- Molecular Screening and Protein Expression Facility, The Wistar Institute, Philadelphia, Pennsylvania
| | - Chih-Chi Andrew Hu
- Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, Texas
| | - Shuai Wu
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania.
| | - Rugang Zhang
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania.
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8
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Lin J, Liu H, Fukumoto T, Zundell J, Yan Q, Tang CHA, Wu S, Zhou W, Guo D, Karakashev S, Hu CCA, Sarma K, Kossenkov AV, Zhang R. Targeting the IRE1α/XBP1s pathway suppresses CARM1-expressing ovarian cancer. Nat Commun 2021; 12:5321. [PMID: 34493732 PMCID: PMC8423755 DOI: 10.1038/s41467-021-25684-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 08/25/2021] [Indexed: 11/10/2022] Open
Abstract
CARM1 is often overexpressed in human cancers including in ovarian cancer. However, therapeutic approaches based on CARM1 expression remain to be an unmet need. Cancer cells exploit adaptive responses such as the endoplasmic reticulum (ER) stress response for their survival through activating pathways such as the IRE1α/XBP1s pathway. Here, we report that CARM1-expressing ovarian cancer cells are selectively sensitive to inhibition of the IRE1α/XBP1s pathway. CARM1 regulates XBP1s target gene expression and directly interacts with XBP1s during ER stress response. Inhibition of the IRE1α/XBP1s pathway was effective against ovarian cancer in a CARM1-dependent manner both in vitro and in vivo in orthotopic and patient-derived xenograft models. In addition, IRE1α inhibitor B-I09 synergizes with immune checkpoint blockade anti-PD1 antibody in an immunocompetent CARM1-expressing ovarian cancer model. Our data show that pharmacological inhibition of the IRE1α/XBP1s pathway alone or in combination with immune checkpoint blockade represents a therapeutic strategy for CARM1-expressing cancers.
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Affiliation(s)
- Jianhuang Lin
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Heng Liu
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Takeshi Fukumoto
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Joseph Zundell
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Qingqing Yan
- grid.251075.40000 0001 1956 6678Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, PA USA
| | - Chih-Hang Anthony Tang
- grid.63368.380000 0004 0445 0041Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX USA
| | - Shuai Wu
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Wei Zhou
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Dajiang Guo
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Sergey Karakashev
- grid.251075.40000 0001 1956 6678Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA USA
| | - Chih-Chi Andrew Hu
- grid.63368.380000 0004 0445 0041Center for Translational Research in Hematologic Malignancies, Houston Methodist Cancer Center, Houston Methodist Research Institute, Houston, TX USA
| | - Kavitha Sarma
- grid.251075.40000 0001 1956 6678Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, PA USA
| | - Andrew V. Kossenkov
- grid.251075.40000 0001 1956 6678Gene Expression and Regulation Program, The Wistar Institute, Philadelphia, PA USA
| | - Rugang Zhang
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, PA, USA.
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9
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Tcyganov EN, Hanabuchi S, Hashimoto A, Campbell D, Kar G, Slidel TW, Cayatte C, Landry A, Pilataxi F, Hayes S, Dougherty B, Hicks KC, Mulgrew K, Tang CHA, Hu CCA, Guo W, Grivennikov S, Ali MAA, Beltra JC, Wherry EJ, Nefedova Y, Gabrilovich DI. Distinct mechanisms govern populations of myeloid-derived suppressor cells in chronic viral infection and cancer. J Clin Invest 2021; 131:e145971. [PMID: 34228641 DOI: 10.1172/jci145971] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 07/01/2021] [Indexed: 12/20/2022] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are major negative regulators of immune responses in cancer and chronic infections. It remains unclear if regulation of MDSC activity in different conditions is controlled by similar mechanisms. We compared MDSCs in mice with cancer and lymphocytic choriomeningitis virus (LCMV) infection. Chronic LCMV infection caused the development of monocytic MDSCs (M-MDSCs) but did not induce polymorphonuclear MDSCs (PMN-MDSCs). In contrast, both MDSC populations were present in cancer models. An acquisition of immune-suppressive activity by PMN-MDSCs in cancer was controlled by IRE1α and ATF6 pathways of the endoplasmic reticulum (ER) stress response. Abrogation of PMN-MDSC activity by blockade of the ER stress response resulted in an increase in tumor-specific immune response and reduced tumor progression. In contrast, the ER stress response was dispensable for suppressive activity of M-MDSCs in cancer and LCMV infection. Acquisition of immune-suppressive activity by M-MDSCs in spleens was mediated by IFN-γ signaling. However, it was dispensable for suppressive activity of M-MDSCs in tumor tissues. Suppressive activity of M-MDSCs in tumors was retained due to the effect of IL-6 present at high concentrations in the tumor site. These results demonstrate disease- and population-specific mechanisms of MDSC accumulation and the need for targeting different pathways to achieve inactivation of these cells.
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Affiliation(s)
- Evgenii N Tcyganov
- Immunology, Microenvironment, and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania, USA
| | | | - Ayumi Hashimoto
- Immunology, Microenvironment, and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania, USA.,AstraZeneca, Gaithersburg, Maryland, USA
| | | | - Gozde Kar
- AstraZeneca, Translational Medicine, Research and Early Development, Oncology Research & Development, Cambridge, United Kingdom
| | - Timothy Wf Slidel
- AstraZeneca, Translational Medicine, Research and Early Development, Oncology Research & Development, Cambridge, United Kingdom
| | | | | | | | | | | | | | | | - Chih-Hang Anthony Tang
- Immunology, Microenvironment, and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Chih-Chi Andrew Hu
- Immunology, Microenvironment, and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Wei Guo
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA
| | - Sergei Grivennikov
- Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA
| | | | - Jean-Christophe Beltra
- Department of Systems Pharmacology and Translational Therapeutics and.,Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Parker Institute for Cancer Immunotherapy at University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - E John Wherry
- Department of Systems Pharmacology and Translational Therapeutics and.,Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Parker Institute for Cancer Immunotherapy at University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yulia Nefedova
- Immunology, Microenvironment, and Metastasis Program, The Wistar Institute, Philadelphia, Pennsylvania, USA
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10
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Ricci D, Tutton S, Marrocco I, Ying M, Blumenthal D, Eletto D, Vargas J, Boyle S, Fazelinia H, Qian L, Suresh K, Taylor D, Paton JC, Paton AW, Tang CHA, Hu CCA, Radhakrishnan R, Gidalevitz T, Argon Y. An interdomain helix in IRE1α mediates the conformational change required for the sensor's activation. J Biol Chem 2021; 296:100781. [PMID: 34000298 PMCID: PMC8203841 DOI: 10.1016/j.jbc.2021.100781] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/07/2021] [Accepted: 05/12/2021] [Indexed: 11/07/2022] Open
Abstract
The unfolded protein response plays an evolutionarily conserved role in homeostasis, and its dysregulation often leads to human disease, including diabetes and cancer. IRE1α is a major transducer that conveys endoplasmic reticulum stress via biochemical signals, yet major gaps persist in our understanding of how the detection of stress is converted to one of several molecular outcomes. It is known that, upon sensing unfolded proteins via its endoplasmic reticulum luminal domain, IRE1α dimerizes and then oligomerizes (often visualized as clustering). Once assembled, the kinase domain trans-autophosphorylates a neighboring IRE1α, inducing a conformational change that activates the RNase effector domain. However, the full details of how the signal is transmitted are not known. Here, we describe a previously unrecognized role for helix αK, located between the kinase and RNase domains of IRE1α, in conveying this critical conformational change. Using constructs containing mutations within this interdomain helix, we show that distinct substitutions affect oligomerization, kinase activity, and the RNase activity of IRE1α differentially. Furthermore, using both biochemical and computational methods, we found that different residues at position 827 specify distinct conformations at distal sites of the protein, such as in the RNase domain. Of importance, an RNase-inactive mutant, L827P, can still dimerize with wildtype monomers, but this mutation inactivates the wildtype molecule and renders leukemic cells more susceptible to stress. We surmise that helix αK is a conduit for the activation of IRE1α in response to stress.
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Affiliation(s)
- Daniela Ricci
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA
| | - Stephen Tutton
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA
| | - Ilaria Marrocco
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA
| | - Mingjie Ying
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Daniel Blumenthal
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA
| | - Daniela Eletto
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA
| | - Jade Vargas
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA
| | - Sarah Boyle
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA
| | - Hossein Fazelinia
- Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Lei Qian
- Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Krishna Suresh
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Deanne Taylor
- Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, Australia
| | - Adrienne W Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide, South Australia, Australia
| | | | | | - Ravi Radhakrishnan
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Tali Gidalevitz
- Department of Biology, Drexel University, Philadelphia, Pennsylvania, USA
| | - Yair Argon
- Division of Cell Pathology, Children's Hospital of Philadelphia and University of Pennsylvania, Civic Center Boulevard, Philadelphia, Pennsylvania, USA.
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11
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Yoshida S, Wei X, Zhang G, O'Connor CL, Torres M, Zhou Z, Lin L, Menon R, Xu X, Zheng W, Xiong Y, Otto E, Tang CHA, Hua R, Verma R, Mori H, Zhang Y, Hu CCA, Liu M, Garg P, Hodgin JB, Sun S, Bitzer M, Qi L. Endoplasmic reticulum-associated degradation is required for nephrin maturation and kidney glomerular filtration function. J Clin Invest 2021; 131:143988. [PMID: 33591954 DOI: 10.1172/jci143988] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 02/11/2021] [Indexed: 02/06/2023] Open
Abstract
Podocytes are key to the glomerular filtration barrier by forming a slit diaphragm between interdigitating foot processes; however, the molecular details and functional importance of protein folding and degradation in the ER remain unknown. Here, we show that the SEL1L-HRD1 protein complex of ER-associated degradation (ERAD) is required for slit diaphragm formation and glomerular filtration function. SEL1L-HRD1 ERAD is highly expressed in podocytes of both mouse and human kidneys. Mice with podocyte-specific Sel1L deficiency develop podocytopathy and severe congenital nephrotic syndrome with an impaired slit diaphragm shortly after weaning and die prematurely, with a median lifespan of approximately 3 months. We show mechanistically that nephrin, a type 1 membrane protein causally linked to congenital nephrotic syndrome, is an endogenous ERAD substrate. ERAD deficiency attenuated the maturation of nascent nephrin, leading to its retention in the ER. We also show that various autosomal-recessive nephrin disease mutants were highly unstable and broken down by SEL1L-HRD1 ERAD, which attenuated the pathogenicity of the mutants toward the WT allele. This study uncovers a critical role of SEL1L-HRD1 ERAD in glomerular filtration barrier function and provides insights into the pathogenesis associated with autosomal-recessive disease mutants.
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Affiliation(s)
- Sei Yoshida
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,State Key Laboratory of Medical Chemical Biology, College of Life Sciences, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, China
| | - Xiaoqiong Wei
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Gensheng Zhang
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Christopher L O'Connor
- Division of Nephrology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Mauricio Torres
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Zhangsen Zhou
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Liangguang Lin
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Rajasree Menon
- Division of Nephrology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Xiaoxi Xu
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Wenyue Zheng
- State Key Laboratory of Medical Chemical Biology, College of Life Sciences, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, China
| | - Yi Xiong
- Center for Molecular Medicine and Genetics, Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Edgar Otto
- Division of Nephrology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Chih-Hang Anthony Tang
- Houston Methodist Cancer Center, Houston Methodist Academic Institute, Houston, Texas, USA
| | - Rui Hua
- State Key Laboratory of Medical Chemical Biology, College of Life Sciences, Frontiers Science Center for Cell Responses, Nankai University, Tianjin, China
| | - Rakesh Verma
- Division of Nephrology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Hiroyuki Mori
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Yang Zhang
- Department of Computational Medicine and Bioinformatics and Department of Biological Chemistry and
| | - Chih-Chi Andrew Hu
- Houston Methodist Cancer Center, Houston Methodist Academic Institute, Houston, Texas, USA
| | - Ming Liu
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Puneet Garg
- Division of Nephrology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | | | - Shengyi Sun
- Center for Molecular Medicine and Genetics, Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Markus Bitzer
- Division of Nephrology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ling Qi
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
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12
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van Anken E, Bakunts A, Hu CCA, Janssens S, Sitia R. Molecular Evaluation of Endoplasmic Reticulum Homeostasis Meets Humoral Immunity. Trends Cell Biol 2021; 31:529-541. [PMID: 33685797 DOI: 10.1016/j.tcb.2021.02.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/02/2021] [Accepted: 02/03/2021] [Indexed: 12/16/2022]
Abstract
The biosynthesis of about one third of the human proteome, including membrane receptors and secreted proteins, occurs in the endoplasmic reticulum (ER). Conditions that perturb ER homeostasis activate the unfolded protein response (UPR). An 'optimistic' UPR output aims at restoring homeostasis by reinforcement of machineries that guarantee efficiency and fidelity of protein biogenesis in the ER. Yet, once the UPR 'deems' that ER homeostatic readjustment fails, it transitions to a 'pessimistic' output, which, depending on the cell type, will result in apoptosis. In this article, we discuss emerging concepts on how the UPR 'evaluates' ER stress, how the UPR is repurposed, in particular in B cells, and how UPR-driven counter-selection of cells undergoing homeostatic failure serves organismal homeostasis and humoral immunity.
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Affiliation(s)
- Eelco van Anken
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy.
| | - Anush Bakunts
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
| | | | - Sophie Janssens
- Laboratory for Endoplasmic Reticulum (ER) Stress and Inflammation, VIB Center for Inflammation Research, and Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Roberto Sitia
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy
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13
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Affiliation(s)
- Juan R Del Valle
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Brian C Betts
- Division of Hematology, Oncology, and Transplantation, University of Minnesota, Minneapolis, MN, USA
| | - Xue-Zhong Yu
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA
| | | | | | - M Celeste Simon
- Abramson Family Cancer Research Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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14
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Shao A, Xu Q, Spalek WT, Cain CF, Kang CW, Tang CHA, Del Valle JR, Hu CCA. Development of Tumor-Targeting IRE-1 Inhibitors for B-cell Cancer Therapy. Mol Cancer Ther 2020; 19:2432-2444. [PMID: 33051362 DOI: 10.1158/1535-7163.mct-20-0127] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 07/02/2020] [Accepted: 10/08/2020] [Indexed: 11/16/2022]
Abstract
The IRE-1 kinase/RNase splices the mRNA of the XBP-1 gene, resulting in the spliced XBP-1 (XBP-1s) mRNA that encodes the functional XBP-1s transcription factor that is critically important for the growth and survival of B-cell leukemia, lymphoma, and multiple myeloma (MM). Several inhibitors targeting the expression of XBP-1s have been reported; however, the cytotoxicity exerted by each inhibitor against cancer cells is highly variable. To design better therapeutic strategies for B-cell cancer, we systematically compared the ability of these compounds to inhibit the RNase activity of IRE-1 in vitro and to suppress the expression of XBP-1s in mouse and human MM cell lines. Tricyclic chromenone-based inhibitors B-I09 and D-F07, prodrugs harboring an aldehyde-masking group, emerged as the most reliable inhibitors for potent suppression of XBP-1s expression in MM cells. The cytotoxicity of B-I09 and D-F07 against MM as well as chronic lymphocytic leukemia and mantle cell lymphoma could be further enhanced by combination with inhibitors of the PI3K/AKT pathway. Because chemical modifications of the salicylaldehyde hydroxy group could be used to tune 1,3-dioxane prodrug stability, we installed reactive oxygen species-sensitive structural cage groups onto these inhibitors to achieve stimuli-responsive activities and improve tumor-targeting efficiency.
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Affiliation(s)
- Andong Shao
- The Wistar Institute, Philadelphia, Pennsylvania
| | - Qin Xu
- The Wistar Institute, Philadelphia, Pennsylvania
| | | | - Christopher F Cain
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana
| | - Chang Won Kang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana
| | | | - Juan R Del Valle
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana.
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15
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Tang CHA, Lee AC, Chang S, Xu Q, Shao A, Lo Y, Spalek WT, Pinilla-Ibarz JA, Del Valle JR, Hu CCA. STING regulates BCR signaling in normal and malignant B cells. Cell Mol Immunol 2020; 18:1016-1031. [PMID: 32999453 PMCID: PMC8115116 DOI: 10.1038/s41423-020-00552-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 09/02/2020] [Indexed: 12/22/2022] Open
Abstract
STING is an endoplasmic reticulum (ER)-resident protein critical for sensing cytoplasmic DNA and promoting the production of type I interferons; however, the role of STING in B cell receptor (BCR) signaling remains unclear. We generated STING V154M knock-in mice and showed that B cells carrying constitutively activated STING specifically degraded membrane-bound IgM, Igα, and Igβ via SEL1L/HRD1-mediated ER-associated degradation (ERAD). B cells with activated STING were thus less capable of responding to BCR activation by phosphorylating Igα and Syk than those without activated STING. When immunized with T-independent antigens, STING V154M mice produced significantly fewer antigen-specific plasma cells and antibodies than immunized wild-type (WT) mice. We further generated B cell-specific STINGKO mice and showed that STINGKO B cells indeed responded to activation by transducing stronger BCR signals than their STING-proficient counterparts. When B cell-specific STINGKO mice were T-independently immunized, they produced significantly more antigen-specific plasma cells and antibodies than immunized STINGWT mice. Since both human and mouse IGHV-unmutated malignant chronic lymphocytic leukemia (CLL) cells downregulated the expression of STING, we explored whether STING downregulation could contribute to the well-established robust BCR signaling phenotype in malignant CLL cells. We generated a STING-deficient CLL mouse model and showed that STING-deficient CLL cells were indeed more responsive to BCR activation than their STING-proficient counterparts. These results revealed a novel B cell-intrinsic role of STING in negatively regulating BCR signaling in both normal and malignant B cells.
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Affiliation(s)
| | - Avery C Lee
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, 19104, USA
| | - Shiun Chang
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, 19104, USA
| | - Qin Xu
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, 19104, USA
| | - Andong Shao
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, 19104, USA
| | - Yun Lo
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, 19104, USA
| | - Walker T Spalek
- The Wistar Institute, 3601 Spruce Street, Philadelphia, PA, 19104, USA
| | - Javier A Pinilla-Ibarz
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, 33612, USA
| | - Juan R Del Valle
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
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16
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Shrestha N, Liu T, Ji Y, Reinert RB, Torres M, Li X, Zhang M, Tang CHA, Hu CCA, Liu C, Naji A, Liu M, Lin JD, Kersten S, Arvan P, Qi L. Sel1L-Hrd1 ER-associated degradation maintains β cell identity via TGF-β signaling. J Clin Invest 2020; 130:3499-3510. [PMID: 32182217 PMCID: PMC7324191 DOI: 10.1172/jci134874] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 03/11/2020] [Indexed: 12/21/2022] Open
Abstract
β Cell apoptosis and dedifferentiation are 2 hotly debated mechanisms underlying β cell loss in type 2 diabetes; however, the molecular drivers underlying such events remain largely unclear. Here, we performed a side-by-side comparison of mice carrying β cell-specific deletion of ER-associated degradation (ERAD) and autophagy. We reported that, while autophagy was necessary for β cell survival, the highly conserved Sel1L-Hrd1 ERAD protein complex was required for the maintenance of β cell maturation and identity. Using single-cell RNA-Seq, we demonstrated that Sel1L deficiency was not associated with β cell loss, but rather loss of β cell identity. Sel1L-Hrd1 ERAD controlled β cell identity via TGF-β signaling, in part by mediating the degradation of TGF-β receptor 1. Inhibition of TGF-β signaling in Sel1L-deficient β cells augmented the expression of β cell maturation markers and increased the total insulin content. Our data revealed distinct pathogenic effects of 2 major proteolytic pathways in β cells, providing a framework for therapies targeting distinct mechanisms of protein quality control.
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Affiliation(s)
- Neha Shrestha
- Department of Molecular and Integrative Physiology, University of Michigan Medical School
| | - Tongyu Liu
- Life Sciences Institute, University of Michigan, and
- Department of Cell and Developmental Biology and
| | - Yewei Ji
- Department of Molecular and Integrative Physiology, University of Michigan Medical School
| | - Rachel B. Reinert
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Mauricio Torres
- Department of Molecular and Integrative Physiology, University of Michigan Medical School
| | - Xin Li
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Maria Zhang
- College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, Michigan, USA
| | - Chih-Hang Anthony Tang
- Immunology, Microenvironment, Metastasis Program, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Chih-Chi Andrew Hu
- Immunology, Microenvironment, Metastasis Program, Wistar Institute, Philadelphia, Pennsylvania, USA
| | - Chengyang Liu
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ali Naji
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ming Liu
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Jiandie D. Lin
- Life Sciences Institute, University of Michigan, and
- Department of Cell and Developmental Biology and
| | - Sander Kersten
- Nutrition, Metabolism and Genomics group, Wageningen University, Wageningen, Netherlands
| | - Peter Arvan
- Department of Molecular and Integrative Physiology, University of Michigan Medical School
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ling Qi
- Department of Molecular and Integrative Physiology, University of Michigan Medical School
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
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17
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Wu Y, Mealer C, Sofi M, Tian L, Bastian D, Schutt S, Choi HJ, Tang CHA, Hu CCA, Yu XZ. STING Negatively Regulates Allogeneic T Cell Responses by Constraining Function of Antigen Presenting Cells. The Journal of Immunology 2020. [DOI: 10.4049/jimmunol.204.supp.87.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Stimulator of interferon genes (STING) plays an important role in eliciting innate immune responses by sensing tumor and microbial DNA in anti-tumor and anti-infection responses, respectively. How the STING signal affects allogeneic response is not clear. To address this question, we utilized murine models of allogeneic hematopoietic stem cell transplantation (allo-HCT). By transferring donor bone marrow (BM) and T cells into allogeneic recipients, we found that significantly more severe graft-versus-host disease (GVHD) was induced in STING−/− recipients as compared to WT controls. By generating BM-chimeric mice in which STING was deficient in hematopoietic or non-hematopoietic antigen-presenting cells (APCs), we confirmed that STING on hematopoietic cells was primarily responsible for constraining host APC function. We further demonstrated that STING on host CD11c+ APCs played a predominant role in the regulation of allogenic T-cell responses. Mechanistically, we found that host CD11c+IAb+ cells deficient for STING could survive better and be activated more strongly after allo-HCT. As a consequence, STING-deficient APCs augmented donor T-cell expansion, chemokine receptor expression and migration into intestinal tissues, resulting accelerated/exacerbated GVHD after allo-HCT. Using pharmacologic approaches, we further demonstrated that systemic administration of STING agonist (c-diGMP) on recipient mice before irradiation significantly reduced GVHD mortality. In conclusion, we reveal a novel role of STING in APC activity that dictates T-cell allogenic responses, and validate STING as a potential therapeutic target for controlling GVHD after allo-HCT.
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Ricci D, Tutton S, Chomistek S, Marrocco I, Ying M, Blumental D, Eletto D, Vargas J, Boyle S, Fazelinia H, Paton J, Paton A, Tang A, Hu CCA, Gidalevitz T, Argon Y. The connector between the kinase and RNase domains of IRE1α differentially controls the activities of this stress sensor. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.03046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Daniela Ricci
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Stephen Tutton
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Steven Chomistek
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Ilaria Marrocco
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Mingjie Ying
- Department of Biology, Drexel University, Philadelphia, PA 19104
| | - Daniel Blumental
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Daniela Eletto
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Jade Vargas
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Sarah Boyle
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - Hossein Fazelinia
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
| | - James Paton
- Department of Biology, Drexel University, Philadelphia, PA 19104
| | - Adrienne Paton
- School of Molecular and Biomedical Science, University of Adelaide, Adelaide, SA, 5005 Australia
| | | | | | - Tali Gidalevitz
- Department of Biology, Drexel University, Philadelphia, PA 19104
| | - Yair Argon
- Division of Cell Pathology, the Children’s Hospital of Philadelphia and the University of Pennsylvania, Civic Center Blvd, Philadelphia, PA 19104
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Liao Y, Tham DKL, Liang FX, Chang J, Wei Y, Sudhir PR, Sall J, Ren SJ, Chicote JU, Arnold LL, Hu CCA, Romih R, Andrade LR, Rindler MJ, Cohen SM, DeSalle R, Garcia-España A, Ding M, Wu XR, Sun TT. Mitochondrial lipid droplet formation as a detoxification mechanism to sequester and degrade excessive urothelial membranes. Mol Biol Cell 2019; 30:2969-2984. [PMID: 31577526 PMCID: PMC6857570 DOI: 10.1091/mbc.e19-05-0284] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The apical surface of the terminally differentiated mammalian urothelial umbrella cell is mechanically stable and highly impermeable, in part due to its coverage by urothelial plaques consisting of 2D crystals of uroplakin particles. The mechanism for regulating the uroplakin/plaque level is unclear. We found that genetic ablation of the highly tissue-specific sorting nexin Snx31, which localizes to plaques lining the multivesicular bodies (MVBs) in urothelial umbrella cells, abolishes MVBs suggesting that Snx31 plays a role in stabilizing the MVB-associated plaques by allowing them to achieve a greater curvature. Strikingly, Snx31 ablation also induces a massive accumulation of uroplakin-containing mitochondria-derived lipid droplets (LDs), which mediate uroplakin degradation via autophagy/lipophagy, leading to the loss of apical and fusiform vesicle plaques. These results suggest that MVBs play an active role in suppressing the excessive/wasteful endocytic degradation of uroplakins. Failure of this suppression mechanism triggers the formation of mitochondrial LDs so that excessive uroplakin membranes can be sequestered and degraded. Because mitochondrial LD formation, which occurs at a low level in normal urothelium, can also be induced by disturbance in uroplakin polymerization due to individual uroplakin knockout and by arsenite, a bladder carcinogen, this pathway may represent an inducible, versatile urothelial detoxification mechanism.
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Affiliation(s)
- Yi Liao
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Daniel K L Tham
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Feng-Xia Liang
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Jennifer Chang
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Yuan Wei
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Putty-Reddy Sudhir
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Joseph Sall
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Sarah J Ren
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Javier U Chicote
- Research Unit, Hospital Joan XXIII, Institut de Investigacio Sanitaria Pere Virgili (IISPV), Universitat Rovira i Virgili, Tarragona 43007, Spain
| | - Lora L Arnold
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Chih-Chi Andrew Hu
- The Wistar Institute, University of Pennsylvania, Philadelphia, PA 19104
| | - Rok Romih
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | | | - Michael J Rindler
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Samuel M Cohen
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Rob DeSalle
- Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024
| | - Antonio Garcia-España
- Research Unit, Hospital Joan XXIII, Institut de Investigacio Sanitaria Pere Virgili (IISPV), Universitat Rovira i Virgili, Tarragona 43007, Spain
| | - Mingxiao Ding
- College of Life Sciences, Peking University, Dachengfang, Haidian, Beijing 100871, China
| | - Xue-Ru Wu
- Department of Urology, New York University School of Medicine, New York, NY10016.,Department of Pathology, New York University School of Medicine, New York, NY10016.,Veterans Affairs Medical Center, New York, NY 10010
| | - Tung-Tien Sun
- Department of Cell Biology, New York University School of Medicine, New York, NY10016.,Department of Urology, New York University School of Medicine, New York, NY10016.,Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY10016.,Department of Dermatology, New York University School of Medicine, New York, NY10016
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20
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Tang CHA, Valle JRD, Hu CCA. Abstract 2661: Targeting endoplasmic reticulum-resident proteins for the treatment of B cell cancer. Cancer Res 2019. [DOI: 10.1158/1538-7445.am2019-2661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
IRE-1 splices XBP-1 mRNAs, leading to activation of the functional XBP-1 transcription factor. We showed that genetic deletion of XBP-1 in chronic lymphocytic leukemia (CLL) cells decelerated malignant progression of CLL in mice. We synthesized and characterized a specific inhibitor, B-I09, which could block the RNase activity of IRE-1 with high potency and efficacy. B-I09 clearly suppressed activation of the IRE-1/XBP-1 pathway, as evidenced by the decreased mRNA and protein levels of XBP-1 in intact cells. B-I09 specifically targeted mouse CLL cells in vivo by inducing apoptosis. Because XBP-1 deficiency could compromise the BCR signaling, a crucial survival signal for CLL, we tested whether pharmacological inhibition of XBP-1 could enhance the effect of inhibitors of the BCR signaling by combining B-I09 with ibrutinib (a Bruton’s tyrosine kinase inhibitor) to treat human CLL cells. A strong pharmacological synergism was determined using the Chou-Talalay combination index method, suggesting that B-I09 could help ibrutinib to achieve higher cytotoxicity at a lower dose, addressing ibrutinib’s toxicity issue. Our studies also led us to discover that IRE-1 interacted with STING, an ER-resident protein critical for cytoplasmic DNA sensing and interferon production. We showed that the IRE-1/XBP-1 pathway was required for the interferon-producing function of STING, and that agonists of STING selectively triggered mitochondria-mediated apoptosis in malignant B cells. Upon stimulation, STING was degraded inefficiently in malignant B cells, implying that prolonged activation of STING could lead to apoptosis. In CLL-bearing mice, injection of the STING agonist, 3'3'-cGAMP, induced apoptosis and regression of leukemia. Similarly efficacious effects were elicited by 3'3'-cGAMP injection in syngeneic or immunodeficient NSG mice grafted with malignant B cells. These data suggested that STING agonists could directly eradicate CLL and other B cell malignancies in vivo. IRE-1 and STING are thus useful ER-resident protein targets for the treatment of B cell cancer.
Citation Format: Chih-Hang Anthony Tang, Juan R. Del Valle, Chih-Chi Andrew Hu. Targeting endoplasmic reticulum-resident proteins for the treatment of B cell cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2661.
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Shao A, Kang CW, Tang CHA, Cain CF, Xu Q, Phoumyvong CM, Del Valle JR, Hu CCA. Structural Tailoring of a Novel Fluorescent IRE-1 RNase Inhibitor to Precisely Control Its Activity. J Med Chem 2019; 62:5404-5413. [PMID: 31083990 DOI: 10.1021/acs.jmedchem.9b00269] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Activation of the IRE-1/XBP-1 pathway has been linked to many human diseases. We report a novel fluorescent tricyclic chromenone inhibitor, D-F07, in which we incorporated a 9-methoxy group onto the chromenone core to enhance its potency and masked the aldehyde to achieve long-term efficacy. Protection of the aldehyde as a 1,3-dioxane acetal led to strong fluorescence emitted by the coumarin chromophore, enabling D-F07 to be tracked inside the cell. We installed a photolabile structural cage on the hydroxy group of D-F07 to generate PC-D-F07. Such a modification significantly stabilized the 1,3-dioxane acetal protecting group, allowing for specific stimulus-mediated control of inhibitory activity. Upon photoactivation, the re-exposed hydroxy group on D-F07 triggered the aldehyde-protecting 1,3-dioxane acetal to slowly decompose, leading to the inhibition of the RNase activity of IRE-1. Our novel findings will also allow for spatiotemporal control of the inhibitory effect of other salicylaldehyde-based compounds currently in development.
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Affiliation(s)
- Andong Shao
- The Wistar Institute , 3601 Spruce Street , Philadelphia , Pennsylvania 19104 , United States
| | - Chang Won Kang
- Department of Chemistry , University of South Florida , Tampa , Florida 33620 , United States
| | - Chih-Hang Anthony Tang
- The Wistar Institute , 3601 Spruce Street , Philadelphia , Pennsylvania 19104 , United States
| | - Christopher F Cain
- Department of Chemistry , University of South Florida , Tampa , Florida 33620 , United States
| | - Qin Xu
- The Wistar Institute , 3601 Spruce Street , Philadelphia , Pennsylvania 19104 , United States
| | - Claire M Phoumyvong
- The Wistar Institute , 3601 Spruce Street , Philadelphia , Pennsylvania 19104 , United States
| | - Juan R Del Valle
- Department of Chemistry , University of South Florida , Tampa , Florida 33620 , United States
| | - Chih-Chi Andrew Hu
- The Wistar Institute , 3601 Spruce Street , Philadelphia , Pennsylvania 19104 , United States
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22
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Tang CH, Chang S, Hashimoto A, Chen YJ, Kang CW, Mato A, Valle JD, Gabrilovich D, Hu CCA. Abstract 4756: Secretory IgM exacerbates tumor progression by inducing accumulations of myeloid-derived suppressor cells in mice. Cancer Res 2018. [DOI: 10.1158/1538-7445.am2018-4756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
To explore the role of B cell receptor (BCR) in promoting malignant progression of chronic lymphocytic leukemia (CLL) in mice, we generate MD4/Eμ-TCL1 mice, whose B cells harbor a monoclonal BCR against hen egg lysozyme (HEL) and secrete IgM against HEL. MD4/Eμ-TCL1 mice survive significantly shorter than Eμ-TCL1 mice. While precancerous B cells in young MD4/Eμ-TCL1 mice recognize HEL, CLL cells developed in older MD4/Eμ-TCL1 mice fail to recognize HEL. Nevertheless, MD4/Eμ-TCL1 CLL cells can be activated by goat F(ab')2 anti-mouse IgM and respond by phosphorylation of Igα, Syk and ERK1/2, indicating reactivation of a parental Ig gene allele. MD4/Eμ-TCL1 CLL cells also produce large quantities of secretory IgM (sIgM), which does not react with HEL. Compared with age-matched Eμ-TCL1 mice, MD4/Eμ-TCL1 mice also generate a significantly increased population of CD11b+/Ly6G+ granulocytic cells in the peripheral blood, spleens and bone marrow. CD11b+/Ly6G+ granulocytic cells purified from spleens of MD4/Eμ-TCL1 mice can suppress CD3/CD28-mediated proliferation of CD8+ T cells and gp100-loaded class I MHC-mediated proliferation of CD8+ T cells from PMEL-1 mice, qualifying these cells as myeloid-derived suppressor cells (MDSCs). Increased MDSCs may account for significantly decreased T cells and poor prognosis in CLL-bearing MD4/Eμ-TCL1 mice. Because MD4/Eμ-TCL1 mouse CLL cells and human CLL cells can produce sIgM, we hypothesize that sIgM may account for the accumulation of MDSCs. To test this hypothesis, we cross μS-/- mice, which cannot produce sIgM, with Eμ-TCL1 mice. The μS-/-/Eμ-TCL1 mice indeed develop significantly lower numbers of MDSCs, and survive significantly longer than Eμ-TCL1 mice. We decide to target the synthesis of sIgM by deleting the function of XBP-1, because the synthesis of sIgM is tightly regulated by a mechanism called regulated IRE-1-dependent decay (RIDD), which is hyperactivated in B cells as a response to XBP-1 deficiency. We cross B cell-specific XBP-1KO mice with MD4/Eμ-TCL1 mice, and the resultant XBP-1KO/MD4/Eμ-TCL1 mice indeed produce significantly reduced amounts of sIgM and decreased numbers of MDSCs. In addition, μS-/- mice grafted with Lewis lung carcinoma exhibit reduced functions of MDSCs in suppressing T cells, resulting in significantly slower tumor growth. These results clearly demonstrate that sIgM produced by B cells can upregulate the immunosuppressive functions of MDSCs in tumor-bearing mice to aggravate cancer progression.
Citation Format: Chih-Hang Tang, Shiun Chang, Ayumi Hashimoto, Yi-Ju Chen, Chang Won Kang, Anthony Mato, Juan Del Valle, Dmitry Gabrilovich, Chih-Chi Andrew Hu. Secretory IgM exacerbates tumor progression by inducing accumulations of myeloid-derived suppressor cells in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4756.
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Tang CHA, Chang S, Paton AW, Paton JC, Gabrilovich DI, Ploegh HL, Del Valle JR, Hu CCA. Phosphorylation of IRE1 at S729 regulates RIDD in B cells and antibody production after immunization. J Cell Biol 2018; 217:1739-1755. [PMID: 29511123 PMCID: PMC5940306 DOI: 10.1083/jcb.201709137] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/23/2018] [Accepted: 02/07/2018] [Indexed: 01/16/2023] Open
Abstract
Phosphorylation of IRE1 at S729 enhances splicing of XBP1 messenger RNA and regulates RIDD. lipopolysaccharide-stimulated plasmablasts from S729A knock-in mice fail to boost spliced XBP1 in response to ER stress. Such mice exhibit plasma cells with decreased numbers and altered functions after immunization. To relieve endoplasmic reticulum (ER) stress, IRE1 splices XBP1 messenger RNA (mRNA) or engages regulated IRE1-dependent decay (RIDD) of other mRNAs. Upon XBP1 deficiency, IRE1 switches to perform RIDD. We examined IRE1 in XBP1-deficient B cells and discovered that IRE1 undergoes phosphorylation at S729. We generated an anti–phospho-S729 antibody to investigate such phosphorylation. Compared with pharmacological ER stress inducers or Toll-like receptor ligands, the bacterial subtilase cytotoxin has an unusual capability in causing rapid and strong phosphorylation at S729 and triggering B cells to express spliced XBP1. To assess the function of S729 in IRE1, we generated S729A knock-in mice and found S729 is critically important for lipopolysaccharide-stimulated plasmablasts to respond to additional ER stress and for antibody production in response to immunization. We further crossed mice carrying an S729A mutation or ΔIRE1 (missing the kinase domain) with B cell–specific XBP1-deficient mice to trigger RIDD and discovered a critical role for S729 in regulating RIDD in B cells.
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Affiliation(s)
| | | | - Adrienne W Paton
- Department of Molecular and Cellular Biology, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | - James C Paton
- Department of Molecular and Cellular Biology, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, Australia
| | | | - Hidde L Ploegh
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
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24
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Betts BC, Locke FL, Sagatys EM, Pidala JA, Walton K, Menges M, Reff J, Djeu JY, Kiluk JV, Lee MC, Kang CW, List AF, Del Valle JR, Hu CCA, Anasetti C. Inhibition of Human Dendritic Cell ER Stress Reduces Gvhd Without Impairing Tregs, NK Cells, or Anti-Tumor Ctl. Biol Blood Marrow Transplant 2018. [DOI: 10.1016/j.bbmt.2017.12.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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25
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Xie H, Tang CHA, Song JH, Mancuso A, Del Valle JR, Cao J, Xiang Y, Dang CV, Lan R, Sanchez DJ, Keith B, Hu CCA, Simon MC. IRE1α RNase-dependent lipid homeostasis promotes survival in Myc-transformed cancers. J Clin Invest 2018; 128:1300-1316. [PMID: 29381485 DOI: 10.1172/jci95864] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 01/16/2018] [Indexed: 12/14/2022] Open
Abstract
Myc activation is a primary oncogenic event in many human cancers; however, these transcription factors are difficult to inhibit pharmacologically, suggesting that Myc-dependent downstream effectors may be more tractable therapeutic targets. Here, we show that Myc overexpression induces endoplasmic reticulum (ER) stress and engages the inositol-requiring enzyme 1α (IRE1α)/X-box binding protein 1 (XBP1) pathway through multiple molecular mechanisms in a variety of c-Myc- and N-Myc-dependent cancers. In particular, Myc-overexpressing cells require IRE1α/XBP1 signaling for sustained growth and survival in vitro and in vivo, dependent on elevated stearoyl-CoA-desaturase 1 (SCD1) activity. Pharmacological and genetic XBP1 inhibition induces Myc-dependent apoptosis, which is alleviated by exogenous unsaturated fatty acids. Of note, SCD1 inhibition phenocopies IRE1α RNase activity suppression in vivo. Furthermore, IRE1α inhibition enhances the cytotoxic effects of standard chemotherapy drugs used to treat c-Myc-overexpressing Burkitt's lymphoma, suggesting that inhibiting the IRE1α/XBP1 pathway is a useful general strategy for treatment of Myc-driven cancers.
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Affiliation(s)
- Hong Xie
- Abramson Family Cancer Research Institute and.,Department of Cancer Biology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Jun H Song
- Abramson Family Cancer Research Institute and.,Department of Cell and Developmental Biology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Juan R Del Valle
- Department of Chemistry, University of South Florida, Tampa, Florida, USA
| | - Jin Cao
- Department of Molecular and Cellular Biology.,Lester and Sue Smith Breast Center, and.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, Texas, USA
| | - Yan Xiang
- Abramson Family Cancer Research Institute and
| | - Chi V Dang
- Abramson Family Cancer Research Institute and
| | - Roy Lan
- Abramson Family Cancer Research Institute and
| | - Danielle J Sanchez
- Abramson Family Cancer Research Institute and.,Department of Cell and Developmental Biology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Brian Keith
- Abramson Family Cancer Research Institute and.,Department of Cancer Biology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - M Celeste Simon
- Abramson Family Cancer Research Institute and.,Department of Cell and Developmental Biology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Tang CH, Chang S, Paton A, Paton J, Gabrilovich D, Ploegh H, Valle JD, Hu CCA. Abstract LB-336: Specific serine phosphorylation of IRE-1 controls enhanced splicing of XBP-1 and regulated IRE-1-dependent decay (RIDD). Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-lb-336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The endoplasmic reticulum (ER) stress sensor IRE-1 is critical for cancer survival and anti-tumor immunity. IRE-1 splices the mRNA of XBP-1 to activate the functional XBP-1s transcription factor or engages regulated IRE-1-dependent decay (RIDD) to degrade tissue-specific mRNAs. It is unclear how IRE-1 RNase activity is regulated to perform the two functions. Upon XBP-1 deficiency, IRE-1 switches to perform RIDD. We examined IRE-1 in XBP-1-deficient B cells, and discovered that IRE-1 undergoes glycosylation at asparagine 178 (N178) and phosphorylation at serine 729 (S729). We generated an anti-phospho-S729 antibody and confirmed that S729 is indeed phosphorylated in XBP-1-deficient B cells. Different from conventional ER stress inducers or Toll-like receptor ligands, subtilase cytotoxin (SubAB), an AB5 toxin produced by Shiga-toxigenic E. coli, has an unusual capability in causing rapid and strong phosphorylation of S729. To further understand the function of N178 and S729 of IRE-1, we generated two knock-in mouse models (N178Q and S729A). Compared with wild-type B cells and those carrying the N178Q mutation, B cells carrying the S729A mutation similarly respond to cues of differentiation by expressing XBP-1s, but they completely fail to respond to pharmacological ER stress inducers or SubAB, suggesting that phosphorylation of S729 is critically important for secondary ER stress response. To evaluate the role of N178, S729 and the kinase domain of IRE-1 in regulating RIDD, we crossed N178Q, S729A and ΔIRE-1 (deletion of amino acids 652 to 751 in the kinase domain) mice with B cell-specific XBP-1KO (CD19Cre/XBP-1f/f) mice to induce RIDD. RIDD was evidenced by the decreased mRNA levels of secretory immunoglobulin (Ig) μ heavy chains in XBP-1-deficient B cells. RIDD was blocked in S729A/XBP-1KO and ΔIRE-1/XBP-1KO but not in N178Q/XBP-1KO B cells. While deleting the kinase function of IRE-1 blocks both XBP-1 splicing and RIDD, mutating S729 only blocks RIDD, highlighting an important role of S729 in regulating RIDD. Since SubAB can efficiently trigger phosphorylation of S729 of IRE-1, we further demonstrated that exposure to SubAB indeed causes RIDD of secretory Ig μ heavy chains in wild-type B cells but not in those carrying the S729A mutation, further supporting the role of S729 in regulating RIDD. In addition, we showed that a potent inhibitor of the IRE-1 RNase, B-I09, can inhibit RIDD. The identification of phosphorylated S729 as a control for RIDD may help scientists devise new ways to specifically target this phosphorylation, contributing to the control of human cancer.
Citation Format: Chih-Hang Tang, Shiun Chang, Adrienne Paton, James Paton, Dmitry Gabrilovich, Hidde Ploegh, Juan Del Valle, Chih-Chi Andrew Hu. Specific serine phosphorylation of IRE-1 controls enhanced splicing of XBP-1 and regulated IRE-1-dependent decay (RIDD) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-336. doi:10.1158/1538-7445.AM2017-LB-336
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Affiliation(s)
| | | | | | - James Paton
- 2University of Adelaide, Adelaide, Australia
| | | | - Hidde Ploegh
- 3Whitehead Institute for Biomedical Research, Cambridge, MA
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Tang CHA, Zundell JA, Ranatunga S, Lin C, Nefedova Y, Del Valle JR, Hu CCA. Agonist-Mediated Activation of STING Induces Apoptosis in Malignant B Cells. Cancer Res 2016; 76:2137-52. [PMID: 26951929 DOI: 10.1158/0008-5472.can-15-1885] [Citation(s) in RCA: 203] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 01/19/2016] [Indexed: 02/05/2023]
Abstract
Endoplasmic reticulum (ER) stress responses through the IRE-1/XBP-1 pathway are required for the function of STING (TMEM173), an ER-resident transmembrane protein critical for cytoplasmic DNA sensing, IFN production, and cancer control. Here we show that the IRE-1/XBP-1 pathway functions downstream of STING and that STING agonists selectively trigger mitochondria-mediated apoptosis in normal and malignant B cells. Upon stimulation, STING was degraded less efficiently in B cells, implying that prolonged activation of STING can lead to apoptosis. Transient activation of the IRE-1/XBP-1 pathway partially protected agonist-stimulated malignant B cells from undergoing apoptosis. In Eμ-TCL1 mice with chronic lymphocytic leukemia, injection of the STING agonist 3'3'-cGAMP induced apoptosis and tumor regression. Similarly efficacious effects were elicited by 3'3'-cGAMP injection in syngeneic or immunodeficient mice grafted with multiple myeloma. Thus, in addition to their established ability to boost antitumoral immune responses, STING agonists can also directly eradicate malignant B cells. Cancer Res; 76(8); 2137-52. ©2016 AACR.
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Affiliation(s)
| | | | - Sujeewa Ranatunga
- Department of Chemistry, University of South Florida, Tampa, Florida
| | - Cindy Lin
- The Wistar Institute, Philadelphia, Pennsylvania
| | | | - Juan R Del Valle
- Department of Chemistry, University of South Florida, Tampa, Florida
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28
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Zhao C, Brown RSH, Tang CHA, Hu CCA, Schlieker C. Site-specific Proteolysis Mobilizes TorsinA from the Membrane of the Endoplasmic Reticulum (ER) in Response to ER Stress and B Cell Stimulation. J Biol Chem 2016; 291:9469-81. [PMID: 26953341 DOI: 10.1074/jbc.m115.709337] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Indexed: 01/01/2023] Open
Abstract
Torsin ATPases are the only representatives of the AAA+ ATPase family that reside in the lumen of the endoplasmic reticulum (ER) and nuclear envelope. Two of these, TorsinA and TorsinB, are anchored to the ER membrane by virtue of an N-terminal hydrophobic domain. Here we demonstrate that the imposition of ER stress leads to a proteolytic cleavage event that selectively removes the hydrophobic domain from the AAA+ domain of TorsinA, which retains catalytic activity. Both the pharmacological inhibition profile and the identified cleavage site between two juxtaposed cysteine residues are distinct from those of presently known proteases, suggesting that a hitherto uncharacterized, membrane-associated protease accounts for TorsinA processing. This processing occurs not only in stress-exposed cell lines but also in primary cells from distinct organisms including stimulated B cells, indicating that Torsin conversion in response to physiologically relevant stimuli is an evolutionarily conserved process. By establishing 5-nitroisatin as a cell-permeable inhibitor for Torsin processing, we provide the methodological framework for interfering with Torsin processing in a wide range of primary cells without the need for genetic manipulation.
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Affiliation(s)
- Chenguang Zhao
- From the Departments of Molecular Biophysics and Biochemistry and
| | | | - Chih-Hang Anthony Tang
- the Department of Translational Tumor Immunology, The Wistar Institute, Philadelphia, Pennsylvania 19104
| | - Chih-Chi Andrew Hu
- the Department of Translational Tumor Immunology, The Wistar Institute, Philadelphia, Pennsylvania 19104
| | - Christian Schlieker
- From the Departments of Molecular Biophysics and Biochemistry and Cell Biology, Yale University, New Haven, Connecticut 06520 and
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29
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Tang CHA, Ranatunga S, Kriss CL, Cubitt CL, Tao J, Pinilla-Ibarz JA, Del Valle JR, Hu CCA. Inhibition of ER stress-associated IRE-1/XBP-1 pathway reduces leukemic cell survival. J Clin Invest 2014; 124:2585-98. [PMID: 24812669 DOI: 10.1172/jci73448] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Activation of the ER stress response is associated with malignant progression of B cell chronic lymphocytic leukemia (CLL). We developed a murine CLL model that lacks the ER stress-associated transcription factor XBP-1 in B cells and found that XBP-1 deficiency decelerates malignant progression of CLL-associated disease. XBP-1 deficiency resulted in acquisition of phenotypes that are disadvantageous for leukemic cell survival, including compromised BCR signaling capability and increased surface expression of sphingosine-1-phosphate receptor 1 (S1P1). Because XBP-1 expression requires the RNase activity of the ER transmembrane receptor IRE-1, we developed a potent IRE-1 RNase inhibitor through chemical synthesis and modified the structure to facilitate entry into cells to target the IRE-1/XBP-1 pathway. Treatment of CLL cells with this inhibitor (B-I09) mimicked XBP-1 deficiency, including upregulation of IRE-1 expression and compromised BCR signaling. Moreover, B-I09 treatment did not affect the transport of secretory and integral membrane-bound proteins. Administration of B-I09 to CLL tumor-bearing mice suppressed leukemic progression by inducing apoptosis and did not cause systemic toxicity. Additionally, B-I09 and ibrutinib, an FDA-approved BTK inhibitor, synergized to induce apoptosis in B cell leukemia, lymphoma, and multiple myeloma. These data indicate that targeting XBP-1 has potential as a treatment strategy, not only for multiple myeloma, but also for mature B cell leukemia and lymphoma.
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MESH Headings
- Adenine/analogs & derivatives
- Animals
- Apoptosis/drug effects
- Cell Line, Tumor
- Cell Survival/drug effects
- DNA-Binding Proteins/antagonists & inhibitors
- DNA-Binding Proteins/deficiency
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Endoplasmic Reticulum Stress/drug effects
- Endoribonucleases/antagonists & inhibitors
- Endoribonucleases/genetics
- Endoribonucleases/metabolism
- Enzyme Inhibitors/chemistry
- Enzyme Inhibitors/pharmacology
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Mice
- Mice, Knockout
- Piperidines
- Protein Serine-Threonine Kinases/antagonists & inhibitors
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Pyrazoles/pharmacology
- Pyrimidines/pharmacology
- Regulatory Factor X Transcription Factors
- Signal Transduction/drug effects
- Transcription Factors/antagonists & inhibitors
- Transcription Factors/deficiency
- Transcription Factors/genetics
- Transcription Factors/metabolism
- X-Box Binding Protein 1
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30
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Ranatunga S, Tang CHA, Kang CW, Kriss CL, Kloppenburg BJ, Hu CCA, Del Valle JR. Synthesis of novel tricyclic chromenone-based inhibitors of IRE-1 RNase activity. J Med Chem 2014; 57:4289-301. [PMID: 24749861 PMCID: PMC4032190 DOI: 10.1021/jm5002452] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
![]()
Inositol-requiring enzyme 1 (IRE-1)
is a kinase/RNase ER stress
sensor that is activated in response to excessive accumulation of
unfolded proteins, hypoxic conditions, calcium imbalance, and other
stress stimuli. Activation of IRE-1 RNase function exerts a cytoprotective
effect and has been implicated in the progression of cancer via increased
expression of the transcription factor XBP-1s. Here, we describe the
synthesis and biological evaluation of novel chromenone-based covalent
inhibitors of IRE-1. Preparation of a family of 8-formyltetrahydrochromeno[3,4-c]pyridines was achieved via a Duff formylation that
is attended by an unusual cyclization reaction. Biological evaluation
in vitro and in whole cells led to the identification of 30 as a potent inhibitor of IRE-1 RNase activity and XBP-1s expression
in wild type B cells and human mantle cell lymphoma cell lines.
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Affiliation(s)
- Sujeewa Ranatunga
- Drug Discovery Department and ‡Department of Immunology, H. Lee Moffitt Cancer Center and Research Institute , 12902 Magnolia Drive MRC3E, Tampa, Florida 33612, United States
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31
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Abstract
Lucentamycin A is a marine-derived peptide natural product harboring a unique 4-ethylidene-3-methylproline (Emp) subunit. The proposed structure of lucentamycin A and the core Emp residue have recently been called into question through synthesis. Here, we report the first total synthesis of lucentamycin A, which confirms that the ethylidene substituent in Emp bears an E geometry, in contrast to the originally assigned Z configuration. Synthesis of the desired (E)-Emp subunit required the implementation of a novel strategy starting from Garner's aldehyde.
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Affiliation(s)
- Sujeewa Ranatunga
- Drug Discovery Department, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, United States
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32
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Kim YB, Balasis ME, Doi K, Berndt N, DuBoulay C, Hu CCA, Guida W, Wang HG, Sebti SM, Del Valle JR. Synthesis and evaluation of substituted hexahydronaphthalenes as novel inhibitors of the Mcl-1/BimBH3 interaction. Bioorg Med Chem Lett 2012; 22:5961-5. [PMID: 22901384 DOI: 10.1016/j.bmcl.2012.07.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 07/10/2012] [Accepted: 07/12/2012] [Indexed: 01/03/2023]
Abstract
Mcl-1, an anti-apoptotic member of the Bcl-2 protein family, is overexpressed in a broad range of human cancers and plays a critical role in conferring resistance to chemotherapy. In the course of screening a natural product-like library of sesquiterpenoid analogs, we identified substituted hexahydronaphthalenes that showed activity against the Mcl-1/BimBH3 interaction in vitro. Here, we describe the synthesis of a small library of analogs and their biological evaluation. The most potent inhibitor in the series (19) exhibits an IC(50) of 8.3 μM by ELISA and disrupts the interaction between endogenously expressed Mcl-1 and Bim in cultured MDA-MB-468 breast cancer cells.
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Affiliation(s)
- Young B Kim
- Drug Discovery Department, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
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33
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Hu CCA, Dougan SK, Winter SV, Paton AW, Paton JC, Ploegh HL. Subtilase cytotoxin cleaves newly synthesized BiP and blocks antibody secretion in B lymphocytes. ACTA ACUST UNITED AC 2009; 206:2429-40. [PMID: 19808260 PMCID: PMC2768844 DOI: 10.1084/jem.20090782] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Shiga-toxigenic Escherichia coli (STEC) use subtilase cytotoxin (SubAB) to interfere with adaptive immunity. Its inhibition of immunoglobulin secretion is both rapid and profound. SubAB favors cleavage of the newly synthesized immunoglobulin heavy chain–binding protein (BiP) to yield a C-terminal fragment that contains BiP’s substrate-binding domain. In the absence of its regulatory nucleotide-binding domain, the SubAB-cleaved C-terminal BiP fragment remains tightly bound to newly synthesized immunoglobulin light chains, resulting in retention of light chains in the endoplasmic reticulum (ER). Immunoglobulins are thus detained in the ER, making impossible the secretion of antibodies by SubAB-treated B cells. The inhibitory effect of SubAB is highly specific for antibody secretion, because other secretory proteins such as IL-6 are released normally from SubAB-treated B cells. Although SubAB also causes BiP cleavage in HepG2 hepatoma cells, (glyco)protein secretion continues unabated in SubAB-exposed HepG2 cells. This specific block in antibody secretion is a novel means of immune evasion for STEC. The differential cleavage of newly synthesized versus “aged” BiP by SubAB in the ER provides insight into the architecture of the ER compartments involved.
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34
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McGehee AM, Dougan SK, Klemm EJ, Shui G, Park B, Kim YM, Watson N, Wenk MR, Ploegh HL, Hu CCA. XBP-1-deficient plasmablasts show normal protein folding but altered glycosylation and lipid synthesis. J Immunol 2009; 183:3690-9. [PMID: 19710472 DOI: 10.4049/jimmunol.0900953] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The accumulation of misfolded secreted IgM in the endoplasmic reticulum (ER) of X-box binding protein 1 (XBP-1)-deficient B cells has been held responsible for the inability of such cells to yield plasma cells, through the failure to mount a proper unfolded protein response. LPS-stimulated B cells incapable of secreting IgM still activate the XBP-1 axis normally, as follows: XBP-1 is turned on by cues that trigger differentiation and not in response to accumulation of unfolded IgM, but the impact of XBP-1 deficiency on glycoprotein folding and assembly has not been explored. The lack of XBP-1 compromised neither the formation of functional hen egg lysozyme-specific IgM nor the secretion of free kappa-chains. Although XBP-1 deficiency affects the synthesis of some ER chaperones, including protein disulfide isomerase, their steady state levels do not drop below the threshold required for proper assembly and maturation of the Igalpha/Igbeta heterodimer and MHC molecules. Intracellular transport and surface display of integral membrane proteins are unaffected by XBP-1 deficiency. Given the fact that we failed to observe any defects in folding of a variety of glycoproteins, we looked for other means to explain the requirement for XBP-1 in plasma cell development. We observed significantly reduced levels of phosphatidylcholine, sphingomyelin, and phosphatidylinositol in total membranes of XBP-1-deficient B cells, and reduced ER content. Terminal N-linked glycosylation of IgM and class I MHC was altered in these cells. XBP-1 hence has important roles beyond folding proteins in the ER.
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Affiliation(s)
- Annette M McGehee
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
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35
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Hu CCA, Dougan SK, McGehee AM, Love JC, Ploegh HL. XBP-1 regulates signal transduction, transcription factors and bone marrow colonization in B cells. EMBO J 2009; 28:1624-36. [PMID: 19407814 PMCID: PMC2684024 DOI: 10.1038/emboj.2009.117] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2009] [Accepted: 03/27/2009] [Indexed: 11/09/2022] Open
Abstract
XBP-1, a transcription factor that drives the unfolded protein response (UPR), is activated in B cells when they differentiate to plasma cells. Here, we show that in the B cells, whose capacity to secrete IgM has been eliminated, XBP-1 is induced normally on induction of differentiation, suggesting that activation of XBP-1 in B cells is a differentiation-dependent event, but not the result of a UPR caused by the abundant synthesis of secreted IgM. Without XBP-1, B cells fail to signal effectively through the B-cell receptor. The signalling defects lead to aberrant expression of the plasma cell transcription factors IRF4 and Blimp-1, and altered levels of activation-induced cytidine deaminase and sphingosine-1-phosphate receptor. Using XBP-1-deficient/Blimp-1-GFP transgenic mice, we find that XBP-1-deficient B cells form antibody-secreting plasmablasts in response to initial immunization; however, these plasmablasts respond ineffectively to CXCL12. They fail to colonize the bone marrow and do not sustain antibody production. These findings define the role of XBP-1 in normal plasma cell development and have implications for management of B-cell malignancies.
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Affiliation(s)
- Chih-Chi Andrew Hu
- Department of Biology, Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge, MA 02142, USA
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36
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Hu CCA, Liang FX, Zhou G, Tu L, Tang CHA, Zhou J, Kreibich G, Sun TT. Assembly of urothelial plaques: tetraspanin function in membrane protein trafficking. Mol Biol Cell 2005; 16:3937-50. [PMID: 15958488 PMCID: PMC1196309 DOI: 10.1091/mbc.e05-02-0136] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The apical surface of mammalian urothelium is covered by 16-nm protein particles packed hexagonally to form 2D crystals of asymmetric unit membranes (AUM) that contribute to the remarkable permeability barrier function of the urinary bladder. We have shown previously that bovine AUMs contain four major integral membrane proteins, i.e., uroplakins Ia, Ib, II, and IIIa, and that UPIa and Ib (both tetraspanins) form heterodimers with UPII and IIIa, respectively. Using a panel of antibodies recognizing different conformational states of uroplakins, we demonstrate that the UPIa-dependent, furin-mediated cleavage of the prosequence of UPII leads to global conformational changes in mature UPII and that UPIb also induces conformational changes in its partner UPIIIa. We further demonstrate that tetraspanins CD9, CD81, and CD82 can stabilize their partner protein CD4. These results indicate that tetraspanin uroplakins, and some other tetraspanin proteins, can induce conformational changes leading to the ER-exit, stabilization, and cell surface expression of their associated, single-transmembrane-domained partner proteins and thus can function as "maturation-facilitators." We propose a model of AUM assembly in which conformational changes in integral membrane proteins induced by uroplakin interactions, differentiation-dependent glycosylation, and the removal of the prosequence of UPII play roles in regulating the assembly of uroplakins to form AUM.
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Affiliation(s)
- Chih-Chi Andrew Hu
- Epithelial Biology Unit, The Ronald O. Perelman Department of Dermatology, New York University School of Medicine, New York, NY 10016, USA
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37
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Tang CHA, Hu CCA, Wei CW, Wang JJ. Synergism of Rana catesbeiana ribonuclease and IFN-gamma triggers distinct death machineries in different human cancer cells. FEBS Lett 2005; 579:265-70. [PMID: 15620724 DOI: 10.1016/j.febslet.2004.11.086] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2004] [Revised: 11/22/2004] [Accepted: 11/24/2004] [Indexed: 10/26/2022]
Abstract
Rana catesbeiana ribonuclease (RC-RNase) possesses tumor-specific cytotoxicity, which can be synergized by IFN-gamma. However, it is unclear how RC-RNase and RC-RNase/IFN-gamma induce cell death. In this study, we use substrate cleavage assays to systematically investigate RC-RNase- and RC-RNase/IFN-gamma-induced caspase activation in HL-60, MCF-7, and SK-Hep-1 cells. We find that RC-RNase and RC-RNase/IFN-gamma induce mitochondria-mediated caspase activation in HL-60 and MCF-7 cells but not in SK-Hep-1 cells, although death of SK-Hep-1 cells is closely related to mitochondrial disruptions. Our findings provide evidence that RC-RNase and RC-RNase/IFN-gamma can kill different cancer cells by distinct mechanisms. Compared with onconase, RC-RNase seems to harbor a more specific anti-cancer activity.
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38
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Chiou CT, Hu CCA, Chen PH, Liao CL, Lin YL, Wang JJ. Association of Japanese encephalitis virus NS3 protein with microtubules and tumour susceptibility gene 101 (TSG101) protein. J Gen Virol 2003; 84:2795-2805. [PMID: 13679614 DOI: 10.1099/vir.0.19201-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Previously reported findings by our group showed that non-structural protein 3 (NS3) of Japanese encephalitis virus (JEV) was localized mainly in the JEV-induced convoluted membrane (CM), which has been proposed to originate from rough endoplasmic reticulum (rER), Golgi apparatus or the trans-Golgi network (TGN), and serves as a reservoir for viral proteins during virus assembly. Earlier findings indicated that NS3 of Kunjin virus interacts with microtubules. In addition, one of the Golgi-associated proteins, tumour susceptibility protein 101 (TSG101), associates with microtubules and is required for budding of retroviral particles. To clarify the association of NS3 with microtubules or with TSG101 during JEV assembly, we applied immunofluorescence, co-immunoprecipitation and immunoelectron microscopic methods. Virus infection, as well as transfection with an NS2B-NS3 expression plasmid, induced microtubule rearrangement. When cells were treated with colchicine, which interferes with microtubule polymerization, NS3 still associated with tubulin and TSG101. Furthermore, tubulin and TSG101 were co-localized with NS3 in the CM by immunogold labelling. Our observations indicate that microtubules and TSG101 associate with NS3, which is incorporated into the JEV-induced structure during JEV replication.
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Affiliation(s)
- Chun-Tang Chiou
- Graduate Institute of Life Sciences, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
| | - Chih-Chi Andrew Hu
- Department of Biology and Anatomy, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
| | - Pi-Hsin Chen
- Department of Biology and Anatomy, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
| | - Ching-Len Liao
- Department of Microbiology and Immunology, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
- Graduate Institute of Life Sciences, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
| | - Yi-Ling Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
- Graduate Institute of Life Sciences, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
| | - Jaang-Jiun Wang
- Department of Biology and Anatomy, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
- Graduate Institute of Life Sciences, National Defense Medical Center, 161 MinChuan E. Rd Sec. 6, Taipei 114, Taiwan
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39
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Deng FM, Liang FX, Tu L, Resing KA, Hu P, Supino M, Hu CCA, Zhou G, Ding M, Kreibich G, Sun TT. Uroplakin IIIb, a urothelial differentiation marker, dimerizes with uroplakin Ib as an early step of urothelial plaque assembly. J Cell Biol 2002; 159:685-94. [PMID: 12446744 PMCID: PMC2173100 DOI: 10.1083/jcb.200204102] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Urothelial plaques consist of four major uroplakins (Ia, Ib, II, and III) that form two-dimensional crystals covering the apical surface of urothelium, and provide unique opportunities for studying membrane protein assembly. Here, we describe a novel 35-kD urothelial plaque-associated glycoprotein that is closely related to uroplakin III: they have a similar overall type 1 transmembrane topology; their amino acid sequences are 34% identical; they share an extracellular juxtamembrane stretch of 19 amino acids; their exit from the ER requires their forming a heterodimer with uroplakin Ib, but not with any other uroplakins; and UPIII-knockout leads to p35 up-regulation, possibly as a compensatory mechanism. Interestingly, p35 contains a stretch of 80 amino acid residues homologous to a hypothetical human DNA mismatch repair enzyme-related protein. Human p35 gene is mapped to chromosome 7q11.23 near the telomeric duplicated region of Williams-Beuren syndrome, a developmental disorder affecting multiple organs including the urinary tract. These results indicate that p35 (uroplakin IIIb) is a urothelial differentiation product structurally and functionally related to uroplakin III, and that p35-UPIb interaction in the ER is an important early step in urothelial plaque assembly.
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Affiliation(s)
- Fang-Ming Deng
- Epithelial Biology Unit, Ronald O. Perelman Department of Dermatology, New York University School of Medicine, New York, NY 10016, USA
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40
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Liu RT, Huang CC, You HL, Chou FF, Hu CCA, Chao FP, Chen CM, Cheng JT. Overexpression of tumor susceptibility gene TSG101 in human papillary thyroid carcinomas. Oncogene 2002; 21:4830-7. [PMID: 12101421 DOI: 10.1038/sj.onc.1205612] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2001] [Revised: 04/17/2002] [Accepted: 04/26/2002] [Indexed: 11/08/2022]
Abstract
Functional inactivation of tumor susceptibility gene tsg101 leads to cellular transformation and tumorigenesis in mice. While human TSG101 is located in a region where frequent loss of heterozygosity can be detected in a variety of cancers, no genomic deletion in TSG101 gene has been reported, casting a doubt on the role of TSG101 as a classical tumor suppressor. Some studies have revealed that TSG101 is a frequent target of splicing defects, which correlate with cellular stress and p53 status. Furthermore, recent reports have identified TSG101 as a part of the MDM2/p53 regulatory circuitry, a well-recognized circuitry that upon deregulation results in tumorigenesis. Interestingly, overexpression of tsg101 from an adventitious promoter also leads to neoplastic transformation. On the basis of this information, we have analysed TSG101 gene expression in 20 human papillary thyroid carcinomas (PTCs) by immunohistochemistry and demonstrated that the overexpression of TSG101 protein is closely associated with human PTCs. Further sequence analysis reveals no mutation in cDNA region encoding steadiness box in these PTC specimens, indicating that the upregulation of TSG101 protein is not caused by the alteration of this region. In situ hybridization analysis confirms that overexpression of TSG101 also occurs at the transcriptional level. In addition, semi-quantitative RT-PCR and subsequent Southern hybridization verify that the amounts of TSG101 transcripts are indeed lower in three normal thyroid tissues than in PTC specimens. Here we report the upregulation of TSG101 expression in PTC cells, providing the first evidence of the association of TSG101 overexpression with human tumors and suggesting that upregulation of TSG101 steady-state level might play a role in mediating tumorigenesis of human PTC.
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Affiliation(s)
- Rue-Tsuan Liu
- Division of Metabolism, Chang Gung Memorial Hospital, Kaohsiung, Taiwan 833, Republic of China
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