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Gong X, Chen T, Lin C, Ping H, Tong X, Zhang K, Chen Z, Cai C, Lu Z, Ke H. Bioinformatics Analysis of the Prognostic Significance of VPS16 in Hepatocellular Carcinoma and Its Role in Drug Screening. BIOMED RESEARCH INTERNATIONAL 2023; 2023:2501596. [PMID: 37124933 PMCID: PMC10137196 DOI: 10.1155/2023/2501596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 05/02/2023]
Abstract
Background Vacuolar protein sorting 16 (VPS16) overexpression was recently considered related to cancer growth and drug resistance; however, little is known about whether VPS16 plays a vital role in liver hepatocellular carcinoma (LIHC). Methods The TIMER2 online database was used to analyze the expression of VPS16 in pancancer, and the Xena Browser was used to explore the correlation between VPS16 expression level and survival time. R language was used to test the survival data of 374 LIHC cases in the TCGA database. DESeq2 was used for differentially expressed gene (DEG) analysis. The HPA database was used to verify the expression level of VPS16 in LIHC. The clusterProfiler package was used to analyze functions and related signaling pathways via GO/KEGG enrichment analysis. Drug sensitivity analysis and molecular docking technology were used to screen the most sensitive drugs targeting VPS16 molecules. Results Pancancer analysis showed that VPS16 was highly expressed in various tumors, especially in LIHC. With the increase in the T stage and grade of LIHC, the expression level of VPS16 was also increased. The expression of VPS16 was negatively correlated with the overall survival of LIHC patients. The stage can be used as an independent prognostic factor. A total of 63 sensitive drugs were found, and 19 drugs were displaying strong molecular binding energy with VPS16. Conclusion VPS16 may be a potential biomarker for the diagnosis and prognosis of LIHC. Drugs targeting VPS16 may be used in the treatment of LIHC in the future.
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Affiliation(s)
- Xiaoming Gong
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
- Department of Radiology, Xianning Central Hospital, The First Affiliated Hospital of Hubei University of Science and Technology, Xianning, Hubei, China
| | - Tao Chen
- Department of Radiology, Xianning Central Hospital, The First Affiliated Hospital of Hubei University of Science and Technology, Xianning, Hubei, China
| | - Cheyu Lin
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
| | - Haiqin Ping
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
| | - Xin Tong
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
| | - Kai Zhang
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
| | - Zhaojun Chen
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
| | - Caiyun Cai
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
| | - Zhiyan Lu
- Department of Radiology, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
| | - Hengning Ke
- Department of Infectious Disease, Hubei AIDS Clinical Training Center, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuchang District 430000, Wuhan, China
- Cancer Research Institute, General Hospital, Ningxia Medical University, Yinchuan, China
- Wuhan Research Center for Infectious Diseases and Cancer, Chinese Academy of Medical Sciences, Wuhan, China
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Targeting the actin/tropomyosin cytoskeleton in epithelial ovarian cancer reveals multiple mechanisms of synergy with anti-microtubule agents. Br J Cancer 2021; 125:265-276. [PMID: 33981016 PMCID: PMC8292367 DOI: 10.1038/s41416-021-01420-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 04/12/2021] [Accepted: 04/22/2021] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Anti-microtubule agents are widely used to treat ovarian cancers, but the efficacy is often compromised by drug resistance. We investigated co-targeting the actin/tropomyosin cytoskeleton and microtubules to increase treatment efficacy in ovarian cancers and potentially overcome resistance. METHODS The presence of tropomyosin-3.1 (Tpm3.1) was examined in clinical specimens from ovarian cancer patients using immunohistochemistry. Combinatorial effects of an anti-Tpm3.1 compound, ATM-3507, with vinorelbine and paclitaxel were evaluated in ovarian cancer cells via MTS and apoptosis assays. The mechanisms of action were established using live- and fixed-cell imaging and protein analysis. RESULTS Tpm3.1 is overexpressed in 97% of tumour tissues (558 of 577) representing all histotypes of epithelial ovarian cancer. ATM-3507 displayed synergy with both anti-microtubule agents to reduce cell viability. Only vinorelbine synergised with ATM-3507 in causing apoptosis. ATM-3507 significantly prolonged vinorelbine-induced mitotic arrest with elevated activity of the spindle assembly checkpoint and mitotic cell death; however, ATM-3507 showed minor impact on paclitaxel-induced mitotic defects. Both combinations substantially increased post-mitotic G1 arrest with cyclin D1 and E1 downregulation and an increase of p21Cip and p27Kip. CONCLUSION Combined targeting of Tpm3.1/actin and microtubules is a promising treatment strategy for ovarian cancer that should be further tested in clinical settings.
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Mohapatra S, Gupta V, Mondal P, Chatterjee S, Bhunia D, Ghosh S. A Small Molecule with Bridged Carbonyl and Tri-fluoro-aceto-phenone Groups Impedes Microtubule Dynamics and Subsequently Triggers Cancer Cell Apoptosis. ChemMedChem 2021; 16:2703-2714. [PMID: 33983670 DOI: 10.1002/cmdc.202100192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 05/13/2021] [Indexed: 11/08/2022]
Abstract
We identified a new microtubule targeted small molecule, which showed significant anticancer activity and induced apoptotic death of cancer cells. Precisely the central bridged carbonyl group and trifluoro-acetophenone group of a bis-benzothiazole molecule (BBT) interacts with tubulin close to the curcumin site and perturbs microtubule dynamics as well as causes microtubule depolymerization. We observed a significant enhancement of fluorescence while BBT interacts with the tubulin through bridged carbonyl moiety, a similar phenomenon to colchicine. Further, BBT activates tumor-suppressing bim and p53-puma axes to inhibit cancer survival. It also shows promising results against a tumor spheroid model. BBT is also capable of tumor regression, which shows that this molecule can serve as a potential template for the design of next-generation microtubule targeted anticancer drugs.
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Affiliation(s)
- Saswat Mohapatra
- Department of Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal, 700032, India
| | - Varsha Gupta
- Department of Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal, 700032, India
| | - Prasenjit Mondal
- Department of Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal, 700032, India
| | - Shreyam Chatterjee
- The Institute of Scientific and Industrial Research, Osaka University, 8-1, Mihogaoka, Ibaraki, Osaka, 567-0047, Japan
| | - Debmalya Bhunia
- Department of Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal, 700032, India
| | - Surajit Ghosh
- Department of Bioscience & Bioengineering, Indian Institute of Technology Jodhpur, NH 62, Surpura Bypass Road, Karwar, Rajasthan, 342037, India.,Department of Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata, West Bengal, 700032, India
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Role of 3′ repressor sequences of p53 in anti-cancer drug sensitivity of human lung tumor cells. Gene 2016; 594:190-196. [DOI: 10.1016/j.gene.2016.08.053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/09/2016] [Accepted: 08/31/2016] [Indexed: 11/24/2022]
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Rovini A, Savry A, Braguer D, Carré M. Microtubule-targeted agents: When mitochondria become essential to chemotherapy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:679-88. [DOI: 10.1016/j.bbabio.2011.01.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 01/02/2011] [Accepted: 01/04/2011] [Indexed: 12/22/2022]
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Li Y, Ligr M, McCarron JP, Daniels G, Zhang D, Zhao X, Ye F, Wang J, Liu X, Osman I, Mencher SK, Lepor H, Wang LG, Ferrari A, Lee P. Natura-alpha targets forkhead box m1 and inhibits androgen-dependent and -independent prostate cancer growth and invasion. Clin Cancer Res 2011; 17:4414-24. [PMID: 21606178 DOI: 10.1158/1078-0432.ccr-11-0431] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE The development of new effective therapeutic agents with minimal side effects for prostate cancer (PC) treatment is much needed. Indirubin, an active molecule identified in the traditional Chinese herbal medicine-Qing Dai (Indigo naturalis), has been used to treat leukemia for decades. However, the anticancer properties of Natura-alpha, an indirubin derivative, are not well studied in solid tumors, particularly in PC. EXPERIMENTAL DESIGN The growth kinetics and invasion ability of on human PC cell lines with or without Natura-alpha treatment were measured by cell proliferation and invasion assays. The antitumor effects of Natura-alpha were examined in nude mice tumor xenograft models, and in a patient with advanced hormone-refractory metastatic PC. Signal network proteins targeted by Natura-alpha were analyzed by using proteomic pathway array analysis (PPAA) on xenografts. RESULTS Natura-alpha inhibited the growth of both androgen-dependent (LNCaP) and androgen-independent (LNCaP-AI, PC-3, and DU145) PC cells with IC(50) between 4 to 10 mmol/L, and also inhibited invasion of androgen-independent PC cells. Its antitumor effects were further evident in in vivo tumor reduction in androgen-dependent and androgen-independent nude mice tumor xenograft models and reduced tumor volume in the patient with hormone refractory metastatic PC. PPAA revealed that antiproliferative and antiinvasive activities of Natura-alpha on PC might primarily be through its downregulation of Forkhead box M1 (FOXM1) protein. Forced overexpression of FOXM1 largely reversed the inhibition of growth and invasion by Natura-alpha. CONCLUSION Natura-alpha could serve as a novel and effective therapeutic agent for treatment of both hormone-sensitive and hormone-refractory PC with minimal side effects.
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Affiliation(s)
- Yirong Li
- Department of Pathology, New York University School of Medicine, New York, New York, USA
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Li Y, Wang L, Zhang M, Melamed J, Liu X, Reiter R, Wei J, Peng Y, Zou X, Pellicer A, Garabedian MJ, Ferrari A, Lee P. LEF1 in androgen-independent prostate cancer: regulation of androgen receptor expression, prostate cancer growth, and invasion. Cancer Res 2009; 69:3332-8. [PMID: 19351848 PMCID: PMC3182465 DOI: 10.1158/0008-5472.can-08-3380] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A major obstacle in treating prostate cancer is the development of androgen-independent disease. In this study, we examined LEF1 expression in androgen-independent cancer as well as its regulation of androgen receptor (AR) expression, prostate cancer growth, and invasion in androgen-independent prostate cancer cells. Affymetrix microarray analysis of LNCaP and LNCaP-AI (androgen-independent variant LNCaP) cells revealed 100-fold increases in LEF1 expression in LNCaP-AI cells. We showed that LEF1 overexpression in LNCaP cells resulted in increased AR expression and consequently enhanced growth and invasion ability, whereas LEF1 knockdown in LNCaP-AI cells decreased AR expression and, subsequently, growth and invasion capacity. Chromatin immunoprecipitation, gel shift, and luciferase assays confirmed LEF1 occupancy and regulation of the AR promoter. Thus, we identified LEF1 as a potential marker for androgen-independent disease and as a key regulator of AR expression and prostate cancer growth and invasion. LEF1 is highly expressed in androgen-independent prostate cancer, potentially serving as a marker for androgen-independent disease.
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Affiliation(s)
- Yirong Li
- Department of Pathology, New York University School of Medicine, NY 10010, USA
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Wang L, Zou X, Berger AD, Twiss C, Peng Y, Li Y, Chiu J, Guo H, Satagopan J, Wilton A, Gerald W, Basch R, Wang Z, Osman I, Lee P. Increased expression of histone deacetylaces (HDACs) and inhibition of prostate cancer growth and invasion by HDAC inhibitor SAHA. Am J Transl Res 2009; 1:62-71. [PMID: 19966939 PMCID: PMC2776287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Accepted: 11/05/2008] [Indexed: 05/28/2023]
Abstract
Histone deacetetylases (HDACs) are a group of corepressors of transcriptional activators and their levels of expression are potentially dysregulated in prostate cancer. Certain inhibitors of histone deacetylases show anti-tumor activity in prostate cancer cell lines. Here, we systemically studied the expression of HDACs in human prostate cancer and the suppression of prostate cancer growth and invasion by HDAC inhibitor SAHA. HDAC1-5 showed increased expression using a combination of DNA microarray, in-situ hybridization, and immunohistochemistry in benign and malignant human prostate tissue as well as RT-PCR and Western blot analysis on various PCa cell lines. Importantly, HDAC inhibitor SAHA suppressed, in particular, prostate cancer cell growth and invasion determined using cell proliferation and Matrigel invasion assays. The findings of this study show that the expression of HDACs and their associated corepressors are increased in prostate cancer in humans and HDAC inhibitor SAHA could serve as a potential therapeutic agent in prostate cancer in addition to anti-androgens.
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Affiliation(s)
- Longgui Wang
- Department of Urology, New York University School of MedicineNew York, NY
| | - Xuanyi Zou
- Department of Pathology, New York University School of MedicineNew York, NY
| | - Aaron D. Berger
- Department of Urology, New York University School of MedicineNew York, NY
| | - Christian Twiss
- Department of Urology, New York University School of MedicineNew York, NY
| | - Yi Peng
- Department of Pathology, New York University School of MedicineNew York, NY
| | - Yirong Li
- Department of Pathology, New York University School of MedicineNew York, NY
| | - Jason Chiu
- Department of Pathology, New York University School of MedicineNew York, NY
| | - Hongfeng Guo
- Department of Pathology, New York University School of MedicineNew York, NY
| | - Jaya Satagopan
- Department of Biostatistics, Memorial Sloan Kettering Cancer CenterNew York, NY
| | - Andrew Wilton
- Department of Biostatistics, Memorial Sloan Kettering Cancer CenterNew York, NY
| | - William Gerald
- Department of Pathology, Memorial Sloan Kettering Cancer CenterNew York, NY
| | - Ross Basch
- Department of Pathology, New York University School of MedicineNew York, NY
| | - Zhengxin Wang
- Department of Cancer Biology, MDAnderson Cancer CenterHouston, TX, USA
| | - Iman Osman
- Department of Urology, New York University School of MedicineNew York, NY
- Department of Dermatology, New York University School of MedicineNew York, NY
- Department of New York Harbor Healthcare SystemNew York, NY
| | - Peng Lee
- Department of Pathology, New York University School of MedicineNew York, NY
- Department of New York Harbor Healthcare SystemNew York, NY
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Colomer R, Llombart-Cussac A, Tusquets I, Rifà J, Mayordomo JI, Ojeda B, Ciruelos E, Hornedo J, Vicente D, Cortés-Funes H. Biweekly gemcitabine plus vinorelbine in first-line metastatic breast cancer: efficacy and correlation with HER2 extracellular domain. Clin Transl Oncol 2006; 8:896-902. [PMID: 17169763 DOI: 10.1007/s12094-006-0153-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Purpose. To assess the toxicity and efficacy of biweekly gemcitabine plus vinorelbine in first-line advanced breast cancer, and to establish whether circulating HER2 ECD levels correlate with the efficacy of the combination. Patients and methods. 52 patients were treated with gemcitabine 2500 mg/m(2) plus vinorelbine 30 mg/m(2), both on day 1 of 14-day cycles, for a maximum of 10 cycles. Baseline serum levels of HER2 ECD were assessed with an ELISA. Results. All patients were evaluable for toxicity, and 50 for efficacy. Overall toxicity was moderate. Grade 3 neutropenia occurred in 35% of patients and grade 4 in 19%. Other grade 3 toxicities were observed in less than 6%. There was one episode of febrile neutropenia, and one death after cycle three. Overall response rate was 52% (95% CI: 38% to 66%), with 2 patients achieving a CR (4%). Response rate did not correlate with HER2 ECD, with 50% of HER2 ECD positive patients responding, vs 48.5% of the HER2 ECD negative. Median overall survival was 24.6 months. Conclusion. Gemcitabine plus vinorelbine, given as an every-two-week schedule, is an active regimen in advanced breast carcinoma. This combination can be an option when anthracyclines and taxanes are not preferred. HER2 ECD has no predictive value in this non-taxane combination.
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Affiliation(s)
- R Colomer
- Institut Catala d'Oncologia, Girona, Spain.
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Wang LG, Ferrari AC. Mithramycin targets sp1 and the androgen receptor transcription level-potential therapeutic role in advanced prostate cancer. TRANSLATIONAL ONCOGENOMICS 2006; 1:19-31. [PMID: 23662037 PMCID: PMC3642134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
UNLABELLED Multiple lines of evidence implicate over-expression and activation of the androgen receptor (AR) in the progression of prostate cancer (PC) to androgen-independence (AI) and resistance to therapy. The mechanisms leading to AR over-expression are not fully understood but binding of Sp1 to specific Sp1-binding sites in the AR promoter and 5'-untranslated region (5'-UTR) was shown to up-regulate AR transcription. In this work, we further characterized the role of Sp1 in the control of AR transcription and explored its potential as a therapeutic target in androgen-dependent (AD) and independent (AI) LNCaP cells. We identified a pair of new Sp1-binding site in the 5'-UTR of AR which we named ARSp1-3. ARSp1-3 binds Sp1 with higher affinity than other known Sp1-binding sites in the promoter/5'-UTR and in transfection experiments, the ARSp1-3 reporter showed higher transcriptional activity in AI than in AD cells. Treatment of these cells with nanomolar concentrations of Mithramycin inhibited binding of Sp1 to its binding sites in the promoter/5'-UTR of the AR gene but more specifically the binding of ARSp1-3 while other regulatory elements of the AR promoter were not affected. Inhibition of Sp1 binding by Mithramycin decreased the AR transcription and transactivation of PSA reporter constructs. At the lowest concentrations, Mithramycin decreased endogenous AR protein and proliferation of AD and AI LNCaP cells. The combinations of Mithramycin with either paclitaxel or bicalutamide were highly synergistic. CONCLUSION Sp1 binding induces AR transcription in LNCaP cells. The higher affinity of ARSp1-3 for Sp1 may support higher AR mRNA levels in AI than AD LNCaP cells. Mithramycin is a potent and specific inhibitor of Sp1 and AR transcription with potential, at very low concentrations, to enhance the efficacy of hormones or taxane based therapy in patients with recurrent or androgen-independent progression that sustain AR expression.
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Affiliation(s)
- Long G. Wang
- Correspondence: Long G. Wang, NYU Cancer Institute, Department of Medicine, New York University School of Medicine, VAMC 18th floor, Room 18003W, Tel: (212) 263-4274; Fax: (212) 2636091;
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Zhang Z, Wang H, Li M, Agrawal S, Chen X, Zhang R. MDM2 is a negative regulator of p21WAF1/CIP1, independent of p53. J Biol Chem 2004; 279:16000-6. [PMID: 14761977 DOI: 10.1074/jbc.m312264200] [Citation(s) in RCA: 206] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The MDM2 oncogene has both p53-dependent and p53-independent activities. We have previously reported that antisense MDM2 inhibitors have significant anti-tumor activity in multiple human cancer models with various p53 statuses (Zhang, Z., Li, M., Wang, H., Agrawal, S., and Zhang, R. (2003) Proc. Natl. Acad. Sci. U. S. A. 100, 11636-11641). We have also provided evidence that MDM2 has a direct role in the regulation of p21, a cyclin-dependent kinase inhibitor. Here we provide evidence supporting functional interaction between MDM2 and p21 in vitro and in vivo. The inhibition of MDM2 with anti-MDM2 antisense oligonucleotide or Short Interference RNA targeting MDM2 significantly elevated p21 protein levels in PC3 cells (p53 null). In contrast, overexpression of MDM2 diminished the p21 level in the same cells by shortening the p21 half-life, an effect reversed by MDM2 antisense inhibition. MDM2 facilitates p21 degradation independent of ubiquitination and the E3 ligase function of MDM2. Instead, MDM2 promotes p21 degradation by facilitating binding of p21 with the proteasomal C8 subunit. The physical interaction between p21 and MDM2 was demonstrated both in vitro and in vivo with the binding region in amino acids 180-298 of the MDM2 protein. In summary, we provide evidence supporting a physical interaction between MDM2 and p21. We also demonstrate that, by reducing p21 protein stability via proteasome-mediated degradation, MDM2 functions as a negative regulator of p21, an effect independent of both p53 and ubiquitination.
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Affiliation(s)
- Zhuo Zhang
- Department of Pharmacology and Toxicology, Division of Clinical Pharmacology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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