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AKT-mediated regulation of chromatin ubiquitylation and tumorigenesis through Mel18 phosphorylation. Oncogene 2021; 40:2422-2436. [PMID: 33664452 DOI: 10.1038/s41388-020-01602-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 11/25/2020] [Accepted: 12/03/2020] [Indexed: 01/31/2023]
Abstract
Polycomb repressor complex 1 (PRC1) is linked to the regulation of gene expression and histone ubiquitylation conformation, which contributes to carcinogenesis. However, the upstream regulators of PRC1 biogenesis machinery remain obscure. Here, we report that the polycomb group-related mammalian gene Mel18 is a target of the protein kinase AKT. AKT phosphorylates Mel18 at T334 to disrupt the interaction between Mel18 and other PRC1 members, leading to attenuated PRC1-dependent ubiquitylation of histone H2A at Lys119. As such, PRC1 target genes, many of which are known oncogenes, are derepressed upon T334-Mel18 phosphorylation, which promotes malignant behaviours, including cell proliferation, tumour formation, migration and invasion, bone and brain metastatic lesion formation. Notably, a positive correlation between AKT activity and pT334-Mel18 is observed, and prognostic models based on p-AKT and pT334-Mel18 that predicted overall survival and distant metastasis-free survival in breast cancer patients are established. These findings have implications for understanding the role of AKT and its associated proteins in chromatin ubiquitylation, and also indicate the AKT-Mel18-H2AK119ub axis as a novel prognostic biomarker and therapeutic target for cancer patients.
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Wang J, Ji H, Zhu Q, Yu X, Du J, Jiang Z. Co-inhibition of BMI1 and Mel18 enhances chemosensitivity of esophageal squamous cell carcinoma in vitro and in vivo. Oncol Lett 2019; 17:5012-5022. [PMID: 31186712 PMCID: PMC6507449 DOI: 10.3892/ol.2019.10160] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 02/20/2019] [Indexed: 12/18/2022] Open
Abstract
Esophageal squamous cell carcinoma (ESCC) accounts for almost 90% of esophageal cancer cases and is the sixth most common cause of cancer-associated mortality worldwide. Cisplatin is the standard therapeutic reagent for ESCC; however, chemoresistance frequently occurs after a few weeks, which leads to ESCC recurrence. Aberrant expression of B lymphoma Mo-MLV insertion region 1 homolog (BMI1) has been reported to activate multiple growth-regulatory pathways, induce antiapoptotic abilities in numerous types of cancer cells and promote chemoresistance. However, to the best of our knowledge, the role of BMI1 in cisplatin-resistant ESCC, and the interaction between BMI1 and its homologue melanoma nuclear protein 18 (Mel18) remain unknown. The present study identified that knockdown of BMI1 promoted cytotoxic effects of cisplatin, and co-inhibition of Mel18 and BMI1 enhanced cisplatin-induced apoptosis and cytotoxicity. Inhibition of BMI1 and Mel18 also suppressed the expression of c-Myc. Furthermore, this combined inhibition sensitized esophageal xenograft tumors to cisplatin to a greater extent compared with BMI1 inhibition alone. In summary, the current study demonstrated that inhibition of BMI1 and Mel18 could increase the sensitivity of esophageal cancer cells to cisplatin via inhibition of c-Myc. Therefore, combined targeting of BMI1 and Mel18 may serve as a promising therapeutic strategy for sensitizing ESCC to chemotherapy.
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Affiliation(s)
- Jiansong Wang
- Department of Thoracic Surgery, Weifang Medical University, Weifang, Shandong 261031, P.R. China
| | - Huaijun Ji
- Department of Thoracic Surgery, Weihai Municipal Hospital, Weihai, Shandong 264200, P.R. China
| | - Qiang Zhu
- Department of Thoracic Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong 250014, P.R. China
| | - Xinshuang Yu
- Department of Radiation Oncology, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong 250014, P.R. China
| | - Juan Du
- Central Laboratory, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong 250014, P.R. China
| | - Zhongmin Jiang
- Department of Thoracic Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong 250014, P.R. China
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Wang XF, Zhang XW, Hua RX, Du YQ, Huang MZ, Liu Y, Cheng YF, Guo WJ. Mel-18 negatively regulates stem cell-like properties through downregulation of miR-21 in gastric cancer. Oncotarget 2018; 7:63352-63361. [PMID: 27542229 PMCID: PMC5325369 DOI: 10.18632/oncotarget.11221] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 07/16/2016] [Indexed: 12/15/2022] Open
Abstract
Mel-18, a polycomb group protein, has been reported to act as a tumor suppressor and be down-regulated in several human cancers including gastric cancer. It was also found that Mel-18 negatively regulates self-renewal of hematopoietic stem cells and breast cancer stem cells (CSCs). This study aimed to clarify its role in gastric CSCs and explore the mechanisms. We found that low-expression of Mel-18 was correlated with poor prognosis and negatively correlated with overexpression of stem cell markers Oct4, Sox2, and Gli1 in 101 gastric cancer tissues. Mel-18 was down-regulated in cultured spheroid cells, which possess CSCs, and overexpression of Mel-18 inhibits cells sphere-forming ability and tumor growth in vivo. Besides, Mel-18 was lower-expressed in ovary metastatic lesions compared with that in primary lesions of gastric cancer, and Mel-18 overexpression inhibited the migration ability of gastric cancer cells. Interestingly, overexpression of Mel-18 resulted in down-regulation of miR-21 in gastric cancer cells and the expression of Mel-18 was negatively correlated with the expression of miR-21 in gastric cancer tissues. Furthermore, miR-21 overexpression partially restored sphere-forming ability, migration potential and chemo-resistance in Mel-18 overexpressing gastric cancer cells. These results suggests Mel-18 negatively regulates stem cell-like properties through downregulation of miR-21 in gastric cancer cells.
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Affiliation(s)
- Xiao-Feng Wang
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiao-Wei Zhang
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Rui-Xi Hua
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yi-Qun Du
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Ming-Zhu Huang
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yong Liu
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yu Fang Cheng
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wei-Jian Guo
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
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Ji H, Cao M, Ren K, Sun N, Wang W, Zhu Q, Zang Q, Jiang Z. Expression and Clinicopathological Significance of Mel-18 and Bmi-1 in Esophageal Squamous Cell Carcinoma. Technol Cancer Res Treat 2017; 16:828-834. [PMID: 28425347 PMCID: PMC5762038 DOI: 10.1177/1533034617705055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The Polycomb group genes are a general class of regulators that are responsible for maintaining homeotic gene expression throughout cell division. Polycomb group expression plays an important role in oncogenesis of several types of human cancer. Melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 are key Polycomb group proteins. Studies have shown that melanoma nuclear protein 18 is a potential tumor suppression, and B-cell-specific Moloney leukemia virus insert site 1 is overexpressed in several human malignancies. However, the roles of melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 in esophageal squamous cell carcinoma are still unclear. In this study, we analyzed the expression levels of melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 in 89 esophageal cancer tissues and paired normal mucosal tissues using immunohistochemistry, Western blotting, and quantitative real-time polymerase chain reaction analyses. We found that the expression of melanoma nuclear protein 18 in the carcinoma tissues was significantly lower than that in the noncancerous mucosal tissues (P < .05), and B-cell-specific Moloney leukemia virus insert site 1 expression in the carcinoma tissues was significantly higher than that in the noncancerous mucosal tissues (P < .05). In addition, the expression of melanoma nuclear protein 18 was correlated with clinical stage, depth of invasion, and lymph node metastasis (P < .05) but was not correlated with gender, age, degree of differentiation, or disease-free survival (P > .05). B-cell-specific Moloney leukemia virus insert site 1 expression was strongly correlated with the degree of differentiation, clinical stage, and lymph node metastasis (P <.05) but was not correlated with the gender, age, depth of invasion or disease-free survival (P > .05). Moreover, there was a negative correlation between melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 expressions in esophageal squamous cell carcinoma (P < .05). Our study suggests that melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 may play a crucial role in esophageal squamous cell carcinoma. Melanoma nuclear protein 18 or B-cell-specific Moloney leukemia virus insert site 1 may be a potential biomarker for diagnosis and prognosis of esophageal squamous cell carcinoma.
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Affiliation(s)
- Huaijun Ji
- Division of Surgery, Graduate Department, Weifang Medical College, Weifang, Shandong, People's Republic of China
| | - Ming Cao
- Department of Thoracic Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong, People's Republic of China
| | - Kunlun Ren
- Division of Surgery, Graduate Department, Weifang Medical College, Weifang, Shandong, People's Republic of China
| | - Ningbo Sun
- Department of Thoracic Surgery, Shengli Oilfield Central Hospital, Dongying, Shandong, People's Republic of China
| | - Wei Wang
- Department of Thoracic Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong, People's Republic of China
| | - Qiang Zhu
- Department of Thoracic Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong, People's Republic of China
| | - Qi Zang
- Department of Thoracic Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong, People's Republic of China
| | - Zhongmin Jiang
- Department of Thoracic Surgery, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong, People's Republic of China
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Chen DH, Huang Y, Ruan Y, Shen WH. The evolutionary landscape of PRC1 core components in green lineage. PLANTA 2016; 243:825-46. [PMID: 26729480 DOI: 10.1007/s00425-015-2451-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 12/16/2015] [Indexed: 05/20/2023]
Abstract
The origin and evolution of plant PRC1 core components. Polycomb repressive complex1 (PRC1) plays critical roles in epigenetic silencing of homeotic genes and determination of cell fate. Animal PRC1 has been well investigated for a long time, whereas plant PRC1 was just confirmed in recent years. It is enigmatic whether PRC1 core components in plants share a common ancestor with those in animals. We evaluated the origin of plant PRC1 RING-finger proteins (RING1 and BMI1) through comparing with the homologs in some representative unikonts and using BMI1- and RING1-like proteins as reciprocal outgroup, finding both PRC1 RING-finger proteins have the earliest origin in mosses, similar to LHP1. Additionally, the gene structure, copy number, and domain organization were analyzed to deeply understand the evolutionary history of plant PRC1 complex. In conclusion, PRC1 RING-finger proteins have independent origins in plants and animals, but convergent evolution might attribute to the conservation of PRC1 complex in plants and animals. Plant LHP1 as the homolog of non-PRC1 protein HP1 was recruited to fulfill the role of Pc counterpart. Gene duplication followed by functional divergence makes a great contribution to evolutionary progress of PRC1 in green plants.
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Affiliation(s)
- Dong-hong Chen
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Hunan Agricultural University, 410128, Changsha, China.
| | - Yong Huang
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Hunan Agricultural University, 410128, Changsha, China
| | - Ying Ruan
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Hunan Agricultural University, 410128, Changsha, China.
| | - Wen-Hui Shen
- College of Bioscience and Biotechnology, International Associated Laboratory of CNRS-Fudan-HUNAU on Plant Epigenome Research, Hunan Agricultural University, 410128, Changsha, China
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, 12 rue du Général Zimmer, 67084, Strasbourg Cedex, France
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Context-dependent actions of Polycomb repressors in cancer. Oncogene 2015; 35:1341-52. [DOI: 10.1038/onc.2015.195] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 04/15/2015] [Accepted: 05/05/2015] [Indexed: 12/21/2022]
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Tao J, Liu YL, Zhang G, Ma YY, Cui BB, Yang YM. Expression and clinicopathological significance of Mel-18 mRNA in colorectal cancer. Tumour Biol 2014; 35:9619-25. [DOI: 10.1007/s13277-014-2220-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 06/10/2014] [Indexed: 10/25/2022] Open
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Benetatos L, Vartholomatos G, Hatzimichael E. Polycomb group proteins and MYC: the cancer connection. Cell Mol Life Sci 2014; 71:257-69. [PMID: 23897499 PMCID: PMC11113285 DOI: 10.1007/s00018-013-1426-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 07/12/2013] [Accepted: 07/15/2013] [Indexed: 01/07/2023]
Abstract
Polycomb group proteins (PcGs) are transcriptional repressors involved in physiological processes whereas PcG deregulation might result in oncogenesis. MYC oncogene is able to regulate gene transcription, proliferation, apoptosis, and malignant transformation. MYC deregulation might result in tumorigenesis with tumor maintenance properties in both solid and blood cancers. Although the interaction of PcG and MYC in cancer was described years ago, new findings are reported every day to explain the exact mechanisms and results of such interactions. In this review, we summarize recent data on the PcG and MYC interactions in cancer, and the putative involvement of microRNAs in the equation.
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Affiliation(s)
- Leonidas Benetatos
- Blood Bank, General Hospital of Preveza, Selefkias 2, 48100, Preveza, Greece,
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Zakrzewska M, Zakrzewski K, Grešner SM, Piaskowski S, Zalewska-Szewczyk B, Liberski PP. Polycomb genes expression as a predictor of poor clinical outcome in children with medulloblastoma. Childs Nerv Syst 2011; 27:79-86. [PMID: 20717685 PMCID: PMC3015167 DOI: 10.1007/s00381-010-1260-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 07/30/2010] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Medulloblastoma is the most frequent type of embryonal tumor in the pediatric population, accounting for 20-25% of all brain tumors in children. Recently, the suspected contribution of the Polycomb group (PcG) genes in medulloblastoma development was described. PcG genes play an important role in developmental processes; they are also involved in the self-renewal of hematopoietic and neural stem cells as well as in malignant transformation. PURPOSE In this study, we evaluated the expression of BMI1and PCGF2, members of family of PcG genes, and their potential target, MYC oncogene, and analyzed their association with demographic and clinical data. MATERIALS AND METHODS Thirty-one children (18 males and 13 females, aged from 0.4 to 17 years) with medulloblastoma were included in this study. The gene's expression level was measured by quantitative real-time PCR, obtained using the two-color multiplexing technique. RESULTS We found that the higher expression levels of BMI1 and PCGF2 genes were associated with significantly decreased patient survival (p = 0.02 and p = 0.012, respectively). Significant differences between gender were found, with a higher expression level of the PCGF2 gene observed among females (p = 0.02). CONCLUSION Our analysis showed correlation between BMI1 and PCGF2 gene's expression and survival in children with medulloblastoma.
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Affiliation(s)
- Magdalena Zakrzewska
- Department of Molecular Pathology and Neuropathology, Chair of Oncology, Medical University of Łódź, Czechosłowacka 8/10, Łódź, Poland.
| | - Krzysztof Zakrzewski
- Department of Neurosurgery, Polish Mother’s Memorial Hospital Research Institute, Rzgowska 281/289, 93-338 Łódź, Poland
| | - Sylwia M. Grešner
- Department of Molecular Pathology and Neuropathology, Chair of Oncology, Medical University of Łódź, Czechosłowacka 8/10, 92-216 Łódź, Poland
| | - Sylwester Piaskowski
- Department of Molecular Pathology and Neuropathology, Chair of Oncology, Medical University of Łódź, Czechosłowacka 8/10, 92-216 Łódź, Poland
| | - Beata Zalewska-Szewczyk
- Department of Pediatrics, Oncology, Hematology and Diabetology, 1st Chair of Pediatrics, Medical University of Łódź, Sporna 36/50, 91-738 Łódź, Poland
| | - Paweł P. Liberski
- Department of Molecular Pathology and Neuropathology, Chair of Oncology, Medical University of Łódź, Czechosłowacka 8/10, 92-216 Łódź, Poland
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Liu H, Ding J, Chen F, Fan B, Gao N, Yang Z, Qi L. Increased expression of elongation factor-1α is significantly correlated with poor prognosis of human prostate cancer. ACTA ACUST UNITED AC 2010; 44:277-83. [PMID: 20545466 DOI: 10.3109/00365599.2010.492787] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Overexpression of elongation factor-1α (EF-1α) has been demonstrated to be related to increased cell proliferation, oncogenic transformation and delayed cell senescence. The purpose of this study was to determine whether EF-1α expression affects the progression of prostate cancer (PCa), and whether it can be used as a prognostic marker for PCa. MATERIAL AND METHODS EF-1α was evaluated by immunostaining in paraffin-embedded specimens of prostates obtained from 80 patients with PCa. Correlations of EF-1α with patients' ages, Gleason scores, American Joint Committee on Cancer (AJCC) stages, International Union Against Cancer (UICC) stages, preoperative prostate-specific antigen (PSA) concentrations and PSA failure were evaluated. Survival in all patients was analysed to evaluate the influence of EF-1α expression in cancer progression using Kaplan-Meier and multivariate Cox regression analysis. RESULTS The positive expression rate of EF-1α in PCa tissues [64/80 (80.0%)] was significantly higher than that in normal prostate tissues [1/20 (5.0%)] (p < 0.001). Increased immunostaining of EF-1α was a significant predictor of distant metastasis-free survival [hazard ratio (HR) 0.386, 95% confidence interval (CI) 0.032-2.519, p = 0.003] and overall survival (HR 0.305, 95% CI 0.091-0.872, p = 0.005). In multivariate analysis including competing biological variables, EF-1α expression was still significantly linked to distant metastasis-free survival (HR 0.216, 95% CI 0.042-0.876, p = 0.015) and overall survival (HR 0.395, 95% CI 0.116-0.798, p = 0.008). CONCLUSION These findings provide convincing evidence for the first time that EF-1α correlates closely with the survival of patients with PCa and may be a novel prognostic marker.
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Affiliation(s)
- Huaizheng Liu
- Department of Urology, Xiang Ya Hospital, Central South University, Changsha City, Hunan Province, PR China
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Zhang XW, Sheng YP, Li Q, Qin W, Lu YW, Cheng YF, Liu BY, Zhang FC, Li J, Dimri GP, Guo WJ. BMI1 and Mel-18 oppositely regulate carcinogenesis and progression of gastric cancer. Mol Cancer 2010; 9:40. [PMID: 20170541 PMCID: PMC2842237 DOI: 10.1186/1476-4598-9-40] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Accepted: 02/21/2010] [Indexed: 12/17/2022] Open
Abstract
Background The BMI1 oncogene is overexpressed in several human malignancies including gastric cancer. In addition to BMI1, mammalian cells also express Mel-18, which is closely related to BMI1. We have reported that Mel-18 functions as a potential tumor suppressor by repressing the expression of BMI1 and consequent downregulation of activated AKT in breast cancer cells. However, the mechanisms of BMI1 overexpression and the role of Mel-18 in other cancers are still not clear. The purpose of this study is to investigate the role of BMI1 and Mel-18 in gastric cancer. Results BMI1 was found to be overexpressed in gastric cancer cell lines and gastric tumors. Overexpression of BMI1 correlated with advanced clinical stage and lymph node metastasis; while the expression of Mel-18 negatively correlated with BMI1. BMI1 but not Mel-18 was found to be an independent prognostic factor. Downregulation of BMI1 by Mel-18 overexpression or knockdown of BMI1 expression in gastric cancer cell lines led to upregulation of p16 (p16INK4a or CDKN2A) in p16 positive cell lines and reduction of phospho-AKT in both p16-positive and p16-negative cell lines. Downregulation of BMI1 was also accompanied by decreased transformed phenotype and migration in both p16- positive and p16-negative gastric cancer cell lines. Conclusions In the context of gastric cancer, BMI1 acts as an oncogene and Mel-18 functions as a tumor suppressor via downregulation of BMI1. Mel-18 and BMI1 may regulate tumorigenesis, cell migration and cancer metastasis via both p16- and AKT-dependent growth regulatory pathways.
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Affiliation(s)
- Xiao-Wei Zhang
- Department of Medical Oncology, Cancer Hospital of Fudan University, 270 Dong An Road, Shanghai 200032, China
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