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Lin S, Tao C, Yan Q, Gao H, Qin L, Zhong Y, Yao Q, Zhang P, Yang J, Zou X, Xiao G. Pip5k1c expression in osteocytes regulates bone remodeling in mice. J Orthop Translat 2024; 45:36-47. [PMID: 38495744 PMCID: PMC10943313 DOI: 10.1016/j.jot.2023.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 10/22/2023] [Accepted: 10/24/2023] [Indexed: 03/19/2024] Open
Abstract
Research background The role of osteocytes in maintaining bone mass has been progressively emphasized. Pip5k1c is the most critical isoform among PIP5KIs, which can regulate cytoskeleton, biomembrane, and Ca2+ release of cells and participate in many processes, such as cell adhesion, differentiation, and apoptosis. However, its expression and function in osteocytes are still unclear. Materials and methods To determine the function of Pip5k1c in osteocytes, the expression of Pip5k1c in osteocytes was deleted by breeding the 10-kb mouse Dmp1-Cre transgenic mice with the Pip5k1cfl/fl mice. Bone histomorphometry, micro-computerized tomography analysis, immunofluorescence staining and western blotting were used to determine the effects of Pip5k1c loss on bone mass. In vitro, we explored the mechanism by siRNA knockdown of Pip5k1c in MLO-Y4 cells. Results Pip5k1c expression was decreased in osteocytes in senescent and osteoporotic tissues both in humans and mice. Loss of Pip5k1c in osteocytes led to a low bone mass in long bones and spines and impaired biomechanical properties in femur, without changes in calvariae. The loss of Pip5k1c resulted in the reduction of the protein level of type 1 collagen in tibiae and MLO-Y4 cells. Osteocyte Pip5k1c loss reduced the osteoblast and bone formation rate with high expression of sclerostin, impacting the osteoclast activities at the same time. Moreover, Pip5k1c loss in osteocytes reduced expression of focal adhesion proteins and promoted apoptosis. Conclusion Our studies demonstrate the critical role and mechanism of Pip5k1c in osteocytes in regulating bone remodeling. The translational potential of this article Osteocyte has been considered to a key role in regulating bone homeostasis. The present study has demonstrated that the significance of Pip5k1c in bone homeostasis by regulating the expression of collagen, sclerostin and focal adhesion expression, which provided a possible therapeutic target against human metabolic bone disease.
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Affiliation(s)
- Sixiong Lin
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, China
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
| | - Chu Tao
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
| | - Qinnan Yan
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
| | - Huanqing Gao
- State Key Laboratory of Genetic Engineering and School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Lei Qin
- Department of Orthopedics, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen, 518000, China
| | - Yiming Zhong
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
| | - Qing Yao
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
| | - Peijun Zhang
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
| | - Jiaming Yang
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
- Department of Orthopaedics & Traumatology, Stem Cells and Regenerative Medicine Laboratory, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, China
| | - Xuenong Zou
- Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, Department of Spinal Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, China
| | - Guozhi Xiao
- Department of Biochemistry, School of Medicine, Southern University of Science and Technology, Guangdong Provincial Key Laboratory of Cell Microenvironment and Disease Research, Shenzhen Key Laboratory of Cell Microenvironment, Shenzhen, 518055, China
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Karami Fath M, Akhavan Masouleh R, Afifi N, Loghmani S, Tamimi P, Fazeli A, Mousavian SA, Falsafi MM, Barati G. PI3K/AKT/mTOR signaling pathway modulation by circular RNAs in breast cancer progression. Pathol Res Pract 2023; 241:154279. [PMID: 36584499 DOI: 10.1016/j.prp.2022.154279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022]
Abstract
The PI3K/Akt/mTOR signaling pathway is responsible for many cellular behaviors, including survival, growth, and proliferation. A newly identified RNA, circular RNA (circRNA), plays a crucial role in the regulation of gene expression. The upregulation of the PI3K/Akt pathway through dysregulated circRNAs promotes breast tumor initiation, growth, and progression. The dysregulation of PI3K/Akt-regulating circRNAs seems to be directly correlated with breast cancer clinical features, including overall survival, tumor size, cancer stage, and lymph node metastasis. In addition, targeting these circRNAs may be a promising option in cancer-targeted therapy. Understanding the molecular pathogenesis of the circRNA-PI3K/AKT axis may give the insight to develop new therapeutic and diagnostic approaches for breast cancer therapy. Here we reviewed the expression and functions of PI3K/AKT-regulating circRNAs, and their correlation with breast cancer clinical features. In addition, the potential of PI3K/AKT-regulating circRNAs as diagnostic/prognostic biomarkers or therapeutic targets was discussed.
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Affiliation(s)
- Mohsen Karami Fath
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | | | - Negin Afifi
- School of Medicine, Islamic Azad University, Qeshm Branch, Qeshm, Iran
| | - Shirin Loghmani
- Faculty of Medicine, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Parham Tamimi
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Alireza Fazeli
- Department of Medical Education, Medical Education Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Seyed Ali Mousavian
- Pharmacy Department, EMU(Eastern Mediterranean University), Famagusta, North Cyprus, Republic of Cyprus
| | | | - Ghasem Barati
- Department of Medical Biotechnology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran; Stem Cell Technology Research Center, Tehran, Iran.
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Fumagalli S, Pende M. S6 kinase 1 at the central node of cell size and ageing. Front Cell Dev Biol 2022; 10:949196. [PMID: 36036012 PMCID: PMC9417411 DOI: 10.3389/fcell.2022.949196] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 07/07/2022] [Indexed: 11/17/2022] Open
Abstract
Genetic evidence in living organisms from yeast to plants and animals, including humans, unquestionably identifies the Target Of Rapamycin kinase (TOR or mTOR for mammalian/mechanistic) signal transduction pathway as a master regulator of growth through the control of cell size and cell number. Among the mTOR targets, the activation of p70 S6 kinase 1 (S6K1) is exquisitely sensitive to nutrient availability and rapamycin inhibition. Of note, in vivo analysis of mutant flies and mice reveals that S6K1 predominantly regulates cell size versus cell proliferation. Here we review the putative mechanisms of S6K1 action on cell size by considering the main functional categories of S6K1 targets: substrates involved in nucleic acid and protein synthesis, fat mass accumulation, retrograde control of insulin action, senescence program and cytoskeleton organization. We discuss how S6K1 may be involved in the observed interconnection between cell size, regenerative and ageing responses.
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Affiliation(s)
| | - Mario Pende
- *Correspondence: Stefano Fumagalli, ; Mario Pende,
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Antitumor Effect of Pseudolaric Acid B Involving Regulation of Notch1/Akt Signaling Response in Human Hepatoma Cell In Vitro. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:5353686. [PMID: 35747382 PMCID: PMC9213129 DOI: 10.1155/2022/5353686] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 12/11/2022]
Abstract
Background Liver cancer, particularly hepatocellular carcinoma (HCC), is the fourth leading cause of cancer-related death worldwide. Sorafenib is a crucial drug for the treatment of advanced HCC, but it is difficult to meet the challenge of increasing clinical demands due to its severe side effects and drug resistance. Hence, development of novel antitumor drugs is urged. Previous studies showed that pseudolaric acid B (PAB) could reduce the expression of protein kinase B (PKB/Akt), a downstream effector of Notch signaling, facilitating cell apoptosis in HCC. The disruption of Notch signaling was verified to exacerbate malignant progression and drug resistance, however, the antitumor effect of PAB on Notch signaling in HCC remains unclear. Thus, this study aims to investigate the anti-HCC effect of PAB in association with the regulation of Notch1/Akt signaling. Methods CCK-8 assay and transwell assay were used to examine the cell proliferation and invasion in Huh7 cells after treatment with PAB and a Notch inhibitor DAPT. Moreover, the cell cycle of Huh7 cells after treatment with PAB was analyzed using flow cytometry. Finally, the changes of Notch1, Jagged1, Hes1, and Akt expression at the protein and mRNA level in Notch1/Akt signaling in Huh7 cells after treatment with PAB and DAPT were analyzed using immunofluorescence assay and real-time qPCR. Results The proliferation rate of Huh7 cells exposed to PAB of 0.5, 1, 2, 4, 8, 10, 20, 40, 80, 100, and 200 μmol/L revealed a time-and dose-dependent decrease in vitro, showing cell cycle arrest at G2/M phase (P < 0.05). Furthermore, compared with the untreated group, at the concentration of 40 μmol/L, the proliferation rate and invasion rate of Huh7 cells in PAB, DAPT, and PAB-DAPT combination (PAB + DAPT) group were significantly decreased (P < 0.05), but the PAB + DAPT showed no synergistic antiproliferation and anti-invasion effect in comparison with PAB treatment alone (P > 0.05). In addition, compared with the untreated group, PAB and DAPT alone significantly downregulated the expression of Notch1, Jagged1, Hes1, Akt mRNA, or/and protein in Huh7 cells (P < 0.05), but there was no significant difference in synergistic downregulated effect between the PAB + DAPT group and the PAB group (P > 0.05). Conclusion PAB can suppress proliferation and invasion of HCC cells through downregulating the expression of Notch1/Akt signaling protein and mRNA, and may be a potential novel antitumor drug candidate for the clinical treatment of HCC in the future.
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Majeed ST, Batool A, Majeed R, Bhat NN, Zargar MA, Andrabi KI. mTORC1 induces eukaryotic translation initiation factor 4E interaction with TOS-S6 kinase 1 and its activation. Cell Cycle 2021; 20:839-854. [PMID: 33938392 DOI: 10.1080/15384101.2021.1901038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Eukaryotic translation initiation factor 4E was recently shown to be a substrate of mTORC1, suggesting it may be a mediator of mTORC1 signaling. Here, we present evidence that eIF4E phosphorylated at S209 interacts with TOS motif of S6 Kinase1 (S6K1). We also show that this interaction is sufficient to overcome rapamycin sensitivity and mTORC1 dependence of S6K1. Furthermore, we show that eIF4E-TOS interaction relieves S6K1 from auto-inhibition due to carboxy terminal domain (CTD) and primes it for hydrophobic motif (HM) phosphorylation and activation in mTORC1 independent manner. We conclude that the role of mTORC1 is restricted to engaging eIF4E with S6K1-TOS motif to influence its state of HM phosphorylation and inducing its activation.
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Affiliation(s)
- Sheikh Tahir Majeed
- Growth Factor Signaling Laboratory, Department of Biotechnology, University of Kashmir, Srinagar, India.,Department of Biotechnology, Central University of Kashmir, Ganderbal, India
| | - Asiya Batool
- Growth Factor Signaling Laboratory, Department of Biotechnology, University of Kashmir, Srinagar, India.,Division of Cancer Pharmacology, Indian Institute of Integrative Medicine, Srinagar, India
| | - Rabiya Majeed
- Growth Factor Signaling Laboratory, Department of Biotechnology, University of Kashmir, Srinagar, India.,Department of Biochemistry, University of Kashmir, Srinagar, India
| | - Nadiem Nazir Bhat
- Growth Factor Signaling Laboratory, Department of Biotechnology, University of Kashmir, Srinagar, India
| | | | - Khurshid Iqbal Andrabi
- Growth Factor Signaling Laboratory, Department of Biotechnology, University of Kashmir, Srinagar, India
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Lu G, Zhou B, He Y, Liu H, Luo S, Amos CI, Lee JE, Yang K, Qureshi A, Han J, Wei Q. Novel genetic variants of PIP5K1C and MVB12B of the endosome-related pathway predict cutaneous melanoma-specific survival. Am J Cancer Res 2020; 10:3382-3394. [PMID: 33163277 PMCID: PMC7642651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 07/22/2020] [Indexed: 06/11/2023] Open
Abstract
Endosomes regulate cell polarity, adhesion, signaling, immunity, and tumor progression, which may influence cancer outcomes. Here we evaluated associations between 36,068 genetic variants of 228 endosome-related pathway genes and cutaneous melanoma disease-specific survival (CMSS) using genotyping data from two previously published genome-wide association studies. The discovery dataset included 858 CM patients with 95 deaths from The University of Texas MD Anderson Cancer Center, and the replication dataset included 409 CM patients with 48 deaths from the Nurses' Health Study (NHS) and the Health Professionals Follow-up Study (HPFS). In multivariate Cox proportional hazards regression analysis, we found that two novel SNPs (PIP5K1C rs11666894 A>C and MVB12B rs12376285 C>T) predicted CMSS, with adjusted hazards ratios of 1.47 (95% confidence interval = 1.15-1.89 and P = 0.002) and 1.73 (1.30-2.31 and 0.0002), respectively. Combined analysis of risk genotypes of these two SNPs revealed a dose-dependent decrease in CMSS associated with an increased number of risk genotypes (P trend = 0.0002). Subsequent expression quantitative trait loci (eQTL) analysis revealed that PIP5K1C rs11666894 was associated with mRNA expression levels in lymphoblastoid cell lines from 373 European descendants (P<0.0001) and that MVB12B rs12376285 was associated with mRNA expression levels in cultured fibroblasts from 605 European-Americans (P<0.0001). Our findings suggest that novel genetic variants of PIP5K1C and MVB12B in the endosome-related pathway genes may be promising prognostic biomarkers for CMSS, but these results need to be validated in future larger studies.
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Affiliation(s)
- Guiqing Lu
- Department of Dermatology, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical UniversityNanjing 210019, Jiangsu, China
- Duke Cancer Institute, Duke University Medical CenterDurham, NC 27710, USA
- Department of Population Health Sciences, Duke University School of MedicineDurham, NC 27710, USA
| | - Bingrong Zhou
- Duke Cancer Institute, Duke University Medical CenterDurham, NC 27710, USA
- Department of Population Health Sciences, Duke University School of MedicineDurham, NC 27710, USA
| | - Yuanmin He
- Duke Cancer Institute, Duke University Medical CenterDurham, NC 27710, USA
- Department of Population Health Sciences, Duke University School of MedicineDurham, NC 27710, USA
| | - Hongliang Liu
- Duke Cancer Institute, Duke University Medical CenterDurham, NC 27710, USA
- Department of Population Health Sciences, Duke University School of MedicineDurham, NC 27710, USA
| | - Sheng Luo
- Department of Biostatistics and Bioinformatics, Duke University School of MedicineDurham, NC 27710, USA
| | - Christopher I Amos
- Institute for Clinical and Translational Research, Baylor College of MedicineHouston, TX 77030, USA
| | - Jeffrey E Lee
- Department of Surgical Oncology, The University of Texas M.D. Anderson Cancer CenterHouston, TX 77030, USA
| | - Keming Yang
- Department of Nutrition, Harvard T.H. Chan School of Public HealthBoston, MA, USA
| | - Abrar Qureshi
- Department of Dermatology, Warren Alpert Medical School, Brown UniversityProvidence, RI 02903, USA
| | - Jiali Han
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s HospitalBoston, MA 02115, USA
- Department of Epidemiology, Fairbanks School of Public Health, Indiana UniversityIndianapolis, IN 46202, USA
| | - Qingyi Wei
- Duke Cancer Institute, Duke University Medical CenterDurham, NC 27710, USA
- Department of Population Health Sciences, Duke University School of MedicineDurham, NC 27710, USA
- Department of Medicine, Duke University School of MedicineDurham, NC 27710, USA
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Murugan AK. mTOR: Role in cancer, metastasis and drug resistance. Semin Cancer Biol 2019; 59:92-111. [PMID: 31408724 DOI: 10.1016/j.semcancer.2019.07.003] [Citation(s) in RCA: 253] [Impact Index Per Article: 50.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 06/14/2019] [Accepted: 07/03/2019] [Indexed: 02/09/2023]
Abstract
Mammalian target of rapamycin (mTOR) is a serine/threonine kinase that gets inputs from the amino acids, nutrients, growth factor, and environmental cues to regulate varieties of fundamental cellular processes which include protein synthesis, growth, metabolism, aging, regeneration, autophagy, etc. The mTOR is frequently deregulated in human cancer and activating somatic mutations of mTOR were recently identified in several types of human cancer and hence mTOR is therapeutically targeted. mTOR inhibitors were commonly used as immunosuppressors and currently, it is approved for the treatment of human malignancies. This review briefly focuses on the structure and biological functions of mTOR. It extensively discusses the genetic deregulation of mTOR including amplifications and somatic mutations, mTOR-mediated cell growth promoting signaling, therapeutic targeting of mTOR and the mechanisms of resistance, the role of mTOR in precision medicine and other recent advances in further understanding the role of mTOR in cancer.
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Affiliation(s)
- Avaniyapuram Kannan Murugan
- Department of Molecular Oncology, King Faisal Specialist Hospital & Research Centre, PO Box 3354, Research Center (MBC 03), Riyadh, 11211, Saudi Arabia.
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Ni W, Li Y, Cai L, Dong C, Fang H, Chen Y, Li H, Yao M, Xiao N. SUMOylation is required for PIPK1γ-driven keratinocyte migration and growth. FEBS J 2019; 286:4709-4720. [PMID: 31276292 DOI: 10.1111/febs.14978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 04/11/2019] [Accepted: 07/02/2019] [Indexed: 12/13/2022]
Abstract
PIPKIγ, a key member of the type I phosphatidylinositol 4-phosphate kinase (PIPKI) family that regulates the spatial-temporal generation of PIP2, has been implicated in diverse biological processes including cell survival, cell polarity, and cell migration. An essential role of PIPKIγ in tumor cells and nerve cells has been established in previous studies. However, the function and regulatory mechanism of PIPKIγ remains incompletely understood. Here, we showed that PIPKIγ can specifically associate with the SUMO-conjugating (E2) enzyme UBC9 and can be SUMOylated both in vivo and in vitro. We further identified that Lys-591 is the critical SUMO-acceptor site of PIPKIγ and that SUMO conjugation at this site is required for PIPKIγ-driven keratinocyte migration and growth. Mechanistically, SUMOylation deficiency significantly disrupts PIPKIγ-mediated generation of intracellular PIP2, rather than the subcellular translocation and protein stability of PIPKIγ. Our findings reveal that PIPKIγ is a novel SUMOylation target and highlight the essential role of PIPKIγ SUMOylation in human keratinocyte function, providing an important orientation for in-depth study of wound repair.
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Affiliation(s)
- Wei Ni
- Cancer Institute of Traditional Chinese Medicine, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, China.,Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China.,Bengbu Medical College, Anhui, China
| | - Ying Li
- Department of Emergency, Qingdao Municipal Hospital, Shandong, China
| | - Lili Cai
- Cancer Institute of Traditional Chinese Medicine, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, China
| | - Changsheng Dong
- Cancer Institute of Traditional Chinese Medicine, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, China
| | - Houshun Fang
- Key Laboratory of Pediatric Hematology and Oncology, Ministry of Health and Pediatric Translational Medicine Institute, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, China
| | - Yao Chen
- Key Laboratory of Pediatric Hematology and Oncology, Ministry of Health and Pediatric Translational Medicine Institute, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, China
| | - Hui Li
- Key Laboratory of Pediatric Hematology and Oncology, Ministry of Health and Pediatric Translational Medicine Institute, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, China
| | - Min Yao
- Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Ning Xiao
- Cancer Institute of Traditional Chinese Medicine, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, China
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Zhang S, Hu B, Lv X, Chen S, Liu W, Shao Z. The Prognostic Role of Ribosomal Protein S6 Kinase 1 Pathway in Patients With Solid Tumors: A Meta-Analysis. Front Oncol 2019; 9:390. [PMID: 31139572 PMCID: PMC6527894 DOI: 10.3389/fonc.2019.00390] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 04/26/2019] [Indexed: 12/26/2022] Open
Abstract
Background: Recent studies supported the predictive role of ribosomal protein S6 kinase 1 (S6K1), phosphorylated S6K1 (p-S6K1), and phosphorylated ribosomal protein S6 (p-S6) for the outcome of cancer patients. However, inconsistent results were acquired across different researches. To comprehensively and quantitatively elucidate their prognostic significance in solid malignancies, the current meta-analysis was carried out utilizing the results of clinical studies. Methods: We conducted the literature retrieval by searching PubMed, Web of Science, EMBASE, and Cochrane library to identify eligible publications. Data were collected from included articles to calculate pooled overall survival (OS), disease-free survival (DFS), recurrence-free survival (RFS), and progression-free survival (PFS). Hazard ratios (HRs) with 95% confidence intervals (CIs) served as appropriate parameters to assess prognostic significance. Results: Forty-four original studies were included, of which 7 studies were analyzed for S6K1, 24 for p-S6K1, and 16 for p-S6. The overexpression of p-S6K1 was significantly associated with poorer prognosis of solid tumor patients in OS (HR = 1.706, 95%CI: 1.369–2.125, p < 0.001), DFS (HR = 1.665, 95%CI: 1.002–2.768, p = 0.049). However, prognostic role of p-S6K1 in RFS and PFS was not found. The result also revealed that S6K1 and p-S6 were significantly associated with reduced OS (HR = 1.691, 95%CI: 1.306–2.189, p < 0.001; HR = 2.019, 95%CI: 1.775–2.296, p < 0.001, respectively). Conclusions: The present meta-analysis demonstrated that elevated expression of S6K1, p-S6K1, or p-S6 might indicate worse prognosis of patients with solid tumors, and supported a promising clinical test to predict solid tumor prognosis based on the level of S6K1 pathway.
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Affiliation(s)
- Shuo Zhang
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Binwu Hu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao Lv
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Songfeng Chen
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Weijian Liu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zengwu Shao
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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The temporal profile of activity-dependent presynaptic phospho-signalling reveals long-lasting patterns of poststimulus regulation. PLoS Biol 2019; 17:e3000170. [PMID: 30822303 PMCID: PMC6415872 DOI: 10.1371/journal.pbio.3000170] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 03/13/2019] [Indexed: 12/23/2022] Open
Abstract
Depolarization of presynaptic terminals stimulates calcium influx, which evokes neurotransmitter release and activates phosphorylation-based signalling. Here, we present the first global temporal profile of presynaptic activity-dependent phospho-signalling, which includes two KCl stimulation levels and analysis of the poststimulus period. We profiled 1,917 regulated phosphopeptides and bioinformatically identified six temporal patterns of co-regulated proteins. The presynaptic proteins with large changes in phospho-status were again prominently regulated in the analysis of 7,070 activity-dependent phosphopeptides from KCl-stimulated cultured hippocampal neurons. Active zone scaffold proteins showed a high level of activity-dependent phospho-regulation that far exceeded the response from postsynaptic density scaffold proteins. Accordingly, bassoon was identified as the major target of neuronal phospho-signalling. We developed a probabilistic computational method, KinSwing, which matched protein kinase substrate motifs to regulated phosphorylation sites to reveal underlying protein kinase activity. This approach allowed us to link protein kinases to profiles of co-regulated presynaptic protein networks. Ca2+- and calmodulin-dependent protein kinase IIα (CaMKIIα) responded rapidly, scaled with stimulus strength, and had long-lasting activity. Mitogen-activated protein kinase (MAPK)/extracellular signal–regulated kinase (ERK) was the main protein kinase predicted to control a distinct and significant pattern of poststimulus up-regulation of phosphorylation. This work provides a unique resource of activity-dependent phosphorylation sites of synaptosomes and neurons, the vast majority of which have not been investigated with regard to their functional impact. This resource will enable detailed characterization of the phospho-regulated mechanisms impacting the plasticity of neurotransmitter release. Analysis of activity-dependent phosphorylation-based signalling in synaptosomes revealed six patterns of long-lasting presynaptic regulation from 1,917 phosphopeptides. The authors identified patterns most likely to be regulated by CamKII and MAPK/ERK and showed the active zone scaffold protein bassoon to be a major signalling target. Neurobiological processes are altered by linking neuronal activity to regulated changes in protein phosphorylation levels that influence protein function. Although some of the major targets of activity-dependent phospho-signalling have been identified, a large number of substrates remain unknown. Here, we have screened systematically for these substrates and extended the list from hundreds to thousands of phosphorylation sites, thereby providing a new depth of understanding. We monitored phospho-signalling for 15 min after the stimulation, which to our knowledge had not been attempted at a large scale. We focused on presynaptic protein substrates of phospho-signalling by isolating the presynaptic terminal. We also stimulated hippocampal neurons but did not monitor the poststimulus. Although the phospho-signalling is immensely complex, the findings could be simplified through data exploration. We identified distinct patterns of presynaptic phospho-regulation across the time course that may constitute co-regulated protein networks. In addition, we found a subset of proteins that had many more phosphorylation sites than the average and high-magnitude responses, implying major signalling or functional roles for these proteins. We also determined the likely protein kinases with the strongest responses to the stimulus at different times using KinSwing, a computational tool that we developed. This resource reveals a new depth of activity-dependent phospho-signalling and identifies major signalling targets, major protein kinases, and co-regulated phosphoprotein networks.
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Durand N, Borges S, Hall T, Bastea L, Döppler H, Edenfield BH, Thompson EA, Geiger X, Storz P. The phosphorylation status of PIP5K1C at serine 448 can be predictive for invasive ductal carcinoma of the breast. Oncotarget 2018; 9:36358-36370. [PMID: 30555634 PMCID: PMC6284740 DOI: 10.18632/oncotarget.26357] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 10/31/2018] [Indexed: 11/25/2022] Open
Abstract
Phosphatidylinositol-4-phosphate 5-kinase type-1C (PIP5K1C) is a lipid kinase that regulates focal adhesion dynamics and cell attachment through site-specific formation of phosphatidylinositol-4,5-bisphosphate (PI4,5P2). By comparing normal breast tissue to carcinoma in situ and invasive ductal carcinoma subtypes, we here show that the phosphorylation status of PIP5K1C at serine residue 448 (S448) can be predictive for breast cancer progression to an aggressive phenotype, while PIP5K1C expression levels are not indicative for this event. PIP5K1C phosphorylation at S448 is downregulated in invasive ductal carcinoma, and similarly, the expression levels of PKD1, the kinase that phosphorylates PIP5K1C at this site, are decreased. Overall, since PKD1 is a negative regulator of cell migration and invasion in breast cancer, the phosphorylation status of this residue may serve as an indicator of aggressiveness of breast tumors.
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Affiliation(s)
- Nisha Durand
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Sahra Borges
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Tavia Hall
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Ligia Bastea
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Heike Döppler
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Brandy H Edenfield
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
| | - E Aubrey Thompson
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
| | | | - Peter Storz
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Mayo Clinic, Jacksonville, FL 32224, USA
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12
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Wang S, Xue X, Wang R, Li X, Li Q, Wang Y, Xie P, Kang Y, Meng R, Feng X. CircZNF609 promotes breast cancer cell growth, migration, and invasion by elevating p70S6K1 via sponging miR-145-5p. Cancer Manag Res 2018; 10:3881-3890. [PMID: 30288120 PMCID: PMC6162997 DOI: 10.2147/cmar.s174778] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Background Accumulating evidence suggests that circular RNAs (circRNAs) play critical roles in carcinomas. However, the contributions of circRNAs to breast cancer remain unclear. Herein, we determined the role of circZNF609 in breast cancer. Methods A total of 143 breast cancer and 38 normal tissues were collected to assess the expression of circZNF609 and its relationship with breast cancer prognosis. A series of in vitro and in vivo functional experiments were carried out to elucidate the role of circZNF609 in breast cancer progression and its underlying molecular mechanisms. Results CircZNF609 was markedly over-expressed in breast cancer tissues and cell lines, and high circZNF609 expression was closely associated with poor outcome. Silencing of circZNF609 inhibited the malignant phenotype of breast cancer in vitro and in vivo. Mechanistically, circ-ZNF609 served as a sponge of miR-145-5p to elevate p70S6K1 expression. Moreover, miR-145-5p overexpression or p70S6K1 knockdown abrogated the oncogenic effects of circZNF609 in breast cancer. In addition, clinically, a strong negative correlation was observed between the expression of circZNF609 and miR-145-5p in breast cancer tissues (r=–0.597, P<0.001), whereas a positive correlation between circZNF609 and p70S6K1 expression (r=0.319, P<0.001). Conclusion These data suggest that circZNF609 contributes to breast cancer progression, at least partly, by modulating the miR-145-5p/p70S6K1 axis, and it may be a potential therapeutic target for breast cancer.
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Affiliation(s)
- Shengting Wang
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Xukai Xue
- Department of Spine Surgery, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, China
| | - Rui Wang
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Xiaoming Li
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Qian Li
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Yufang Wang
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Peijun Xie
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Yuhua Kang
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Rui Meng
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
| | - Xinghua Feng
- Department of Clinical Medicine, Peihua University, Xi'an 710125, China,
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13
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Li L, Kołodziej T, Jafari N, Chen J, Zhu H, Rajfur Z, Huang C. Cdk5-mediated phosphorylation regulates phosphatidylinositol 4-phosphate 5-kinase type I γ 90 activity and cell invasion. FASEB J 2018; 33:631-642. [PMID: 30040488 DOI: 10.1096/fj.201800296r] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Phosphatidylinositol 4-phosphate 5-kinase type I γ (PIPKIγ90) regulates cell migration, invasion, and metastasis. However, it is unknown how cellular signals regulate those processes. Here, we show that cyclin-dependent kinase 5 (Cdk5), a protein kinase that regulates cell migration and invasion, phosphorylates PIPKIγ90 at S453, and that Cdk5-mediated PIPKIγ90 phosphorylation is essential for cell invasion. Moreover, Cdk5-mediated phosphorylation down-regulates the activity of PIPKIγ90 and the secretion of fibronectin, an extracellular matrix protein that regulates cell migration and invasion. Furthermore, inhibition of PIPKIγ activity with the chemical inhibitor UNC3230 suppresses fibronectin secretion in a dose-dependent manner, whereas depletion of Cdk5 enhances fibronectin secretion. With total internal reflection fluorescence microscopy, we found that secreted fibronectin appears as round dots, which colocalize with Tks5 and CD9 but not with Zyxin. These data suggest that Cdk5-mediated PIPKIγ90 phosphorylation regulates cell invasion by controlling PIPKIγ90 activity and fibronectin secretion.-Li, L., Kołodziej, T., Jafari, N., Chen, J., Zhu, H., Rajfur, Z., Huang, C. Cdk5-mediated phosphorylation regulates phosphatidylinositol 4-phosphate 5-kinase type I γ 90 activity and cell invasion.
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Affiliation(s)
- Liqing Li
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA
| | - Tomasz Kołodziej
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA.,Faculty of Physics, Astronomy, and Applied Computer Science, Institute of Physics, Jagiellonian University, Krakow, Poland
| | - Naser Jafari
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA
| | - Jing Chen
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, USA; and
| | - Haining Zhu
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, USA; and
| | - Zenon Rajfur
- Faculty of Physics, Astronomy, and Applied Computer Science, Institute of Physics, Jagiellonian University, Krakow, Poland
| | - Cai Huang
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
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14
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Esaki N, Ohkawa Y, Hashimoto N, Tsuda Y, Ohmi Y, Bhuiyan RH, Kotani N, Honke K, Enomoto A, Takahashi M, Furukawa K, Furukawa K. ASC amino acid transporter 2, defined by enzyme-mediated activation of radical sources, enhances malignancy of GD2-positive small-cell lung cancer. Cancer Sci 2018; 109:141-153. [PMID: 29151270 PMCID: PMC5765286 DOI: 10.1111/cas.13448] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 10/31/2017] [Accepted: 11/12/2017] [Indexed: 12/20/2022] Open
Abstract
Ganglioside GD2 is specifically expressed in small‐cell lung cancer (SCLC) cells, leading to enhancement of malignant phenotypes, such as cell proliferation and migration. However, how GD2 promotes malignant phenotypes in SCLC cells is not well known. In this study, to reveal the mechanisms by which GD2 increases malignant phenotypes in SCLC cells, we used enzyme‐mediated activation of radical sources combined with mass spectrometry in GD2+SCLC cells. Consequently, we identified ASC amino acid transporter 2 (ASCT2), a major glutamine transporter, which coordinately works with GD2. We showed that ASCT2 was highly expressed in glycolipid‐enriched microdomain/rafts in GD2+SCLC cells, and colocalized with GD2 in both proximity ligation assay and immunocytostaining, and bound with GD2 in immunoprecipitation/TLC immunostaining. Malignant phenotypes of GD2+SCLC cells were enhanced by glutamine uptake, and were suppressed by L‐γ‐glutamyl‐p‐nitroanilide, a specific inhibitor of ASCT2, through reduced phosphorylation of p70 S6K1 and S6. These results suggested that ASCT2 enhances glutamine uptake in glycolipid‐enriched microdomain/rafts in GD2+SCLC cells, leading to the enhancement of cell proliferation and migration through increased phosphorylation of the mTOR complex 1 signaling axis.
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Affiliation(s)
- Nobutoshi Esaki
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Kasugai, Japan.,Departments of Biochemistry 2, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuki Ohkawa
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Kasugai, Japan
| | - Noboru Hashimoto
- Departments of Biochemistry 2, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuhsuke Tsuda
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Kasugai, Japan.,Departments of Biochemistry 2, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuhsuke Ohmi
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Kasugai, Japan
| | - Robiul H Bhuiyan
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Kasugai, Japan
| | - Norihiro Kotani
- Department of Biochemistry, Saitama Medical University, Moroyama, Japan
| | - Koichi Honke
- Department of Biochemistry, Kochi University School of Medicine, Kochi, Japan
| | - Atsushi Enomoto
- Departments of Pathology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masahide Takahashi
- Departments of Pathology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Keiko Furukawa
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Kasugai, Japan
| | - Koichi Furukawa
- Department of Biomedical Sciences, Chubu University College of Life and Health Sciences, Kasugai, Japan
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15
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Li L, Li X, Qi L, Rychahou P, Jafari N, Huang C. The role of talin2 in breast cancer tumorigenesis and metastasis. Oncotarget 2017; 8:106876-106887. [PMID: 29290996 PMCID: PMC5739781 DOI: 10.18632/oncotarget.22449] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 10/25/2017] [Indexed: 12/19/2022] Open
Abstract
Recent studies show that talin2 has a higher affinity to β-integrin tails and is indispensable for traction force generation and cell invasion. However, its roles in cell migration, cancer cell metastasis and tumorigenesis remain to be determined. Here, we used MDA-MB-231 human breast cancer cells as a model to define the roles of talin2 in cell migration, invasion, metastasis and tumorigenesis. We show here that talin2 knockdown (KD) inhibited cell migration and focal adhesion dynamics, a key step in cell migration, and that talin2 knockout (KO) inhibited cell invasion and traction force generation, the latter is crucial for cell invasion. Re-expression of talin2WT in talin2-KO cells restored traction force generation and cell invasion, but that of talin2S339C, a β-integrin-binding deficient mutant, did not. Moreover, talin2 KO (or KD) suppressed tumorigenesis and metastasis in mouse xenograft models. However, surprisingly, re-expression of talin2WT in talin2-KO cells did not rescue tumorigenesis. Thus, talin2 is required for breast cancer cell migration, invasion, metastasis and tumorigenesis, although exogenous expression of high levels of talin2 could inhibit tumorigenesis.
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Affiliation(s)
- Liqing Li
- Markey Cancer Center, University of Kentucky, Lexington, KY 40506, USA
| | - Xiang Li
- Markey Cancer Center, University of Kentucky, Lexington, KY 40506, USA
| | - Lei Qi
- Markey Cancer Center, University of Kentucky, Lexington, KY 40506, USA
| | - Piotr Rychahou
- Markey Cancer Center, University of Kentucky, Lexington, KY 40506, USA
| | - Naser Jafari
- Markey Cancer Center, University of Kentucky, Lexington, KY 40506, USA
| | - Cai Huang
- Markey Cancer Center, University of Kentucky, Lexington, KY 40506, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY 40506, USA
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16
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Smurf1 regulates lung cancer cell growth and migration through interaction with and ubiquitination of PIPKIγ. Oncogene 2017; 36:5668-5680. [DOI: 10.1038/onc.2017.166] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 03/31/2017] [Accepted: 04/26/2017] [Indexed: 12/12/2022]
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17
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The molecular basis of talin2's high affinity toward β1-integrin. Sci Rep 2017; 7:41989. [PMID: 28155884 PMCID: PMC5290461 DOI: 10.1038/srep41989] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 01/04/2017] [Indexed: 01/16/2023] Open
Abstract
Talin interacts with β-integrin tails and actin to control integrin activation, thus regulating focal adhesion dynamics and cell migration. There are two talin genes, Tln1 and Tln2, which encode talin1 and talin2, and it is generally believed that talin2 functions redundantly with talin1. However, we show here that talin2 has a higher affinity to β1-integrin tails than talin1. Mutation of talin2 S339 to leucine, which can cause Fifth Finger Camptodactyly, a human genetic disease, completely disrupted its binding to β–integrin tails. Also, substitution of talin1 C336 with Ser enhanced the affinity of talin1, whereas substitution of talin2 S339 with Cys diminished that of talin2. Further computational modeling analysis shows that talin2 S339 formed a hydrogen bond with E353, which is critical for inducing key hydrogen bonds between talin2 N326 and β1-integrin R760, and between talin2 K327 and β1-integrin D759. Mutation at any of these residues significantly diminished the interaction of talin2 with β1- integrin tails. These hydrogen bonds were not observed in talin1/β1-integrin, but did exist in talin1C336S/β1-integrin complex. These results suggest that talin2 S339 forms a hydrogen bond with E353 to mediate its high affinity to β1-integrin.
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