Meng Jiao1,2, Mei Qi3, Facai Zhang4, Jing Hu1, Tingting Feng1, Mingfeng Zhao5, Xinjun Li6, Hui Liu1, Wei Teng7, Jing Zhang8, Zhiyan Liu1,3, Lili Zhang9, Zhen Wu1, Bo Han1,3. 1. The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Pathology, School of Basic Medical Sciences, Shandong University, Jinan, China. 2. Department of Pathology, Second Hospital of Shandong University, Jinan, China. 3. Department of Pathology, Shandong University Qilu Hospital, Jinan, China. 4. Department of Urology, The Affiliated Hospital of Guizhou Medical University, Guizhou, China. 5. Department of Pathology, Binzhou Medical University, Binzhou, China. 6. Department of Pathology, Binzhou People's Hospital, Binzhou, China. 7. Education Quality Management Office, Institute of Continuing Education, Shandong University, Jinan, China. 8. Department of Pharmacy, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, China. 9. State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China.
Abstract
BACKGROUND: Cancer stem-like traits contribute to prostate cancer (PCa) progression and metastasis. Cullin 4B (CUL4B) is a member of the ubiquitin E3 ligase family and overexpressed in several solid malignancies including PCa. CUL4B has been suggested to be an oncogene through epigenetic repression of tumor suppressors. However, the link between CUL4B expression and cancer stem-like phenotype remains unclear. METHODS: Western blot analysis, sphere formation, and colony formation assays were used to examine the effect of CUL4B on cancer stem-like traits in PCa cells. Mechanically, bioinformatic analysis was utilized to evaluate whether BMI1 was a target of CUL4B. Moreover, real-time polymerase chain reaction, chromatin immunoprecipitation, and luciferase reporter assays were performed to identify microRNAs regulated by CUL4B. Finally, Western blot assay was used to validate the regulation of CUL4B, miR200b, and miR200c (miR200b/c) on the stem-like characteristics of PCa cells. RESULTS: CUL4B promotes PCa pluripotency-associated markers expression, sphere formation, and anchorage-independent growth ability in vitro. Mechanically, CUL4B upregulates BMI1 expression via epigenetically repressing miR200b/c expression. In addition, miR200b/c could partially reverse CUL4B-induced BMI1 and pluripotency-associated marker expression. CONCLUSIONS: Our study revealed that CUL4B regulates cancer stem-like traits of prostate cancer cells by targeting BMI1 via miR200b/c, which might give novel insight into how CUL4B promotes PCa progression through regulating cancer stem-like traits.
BACKGROUND:Cancer stem-like traits contribute to prostate cancer (PCa) progression and metastasis. Cullin 4B (CUL4B) is a member of the ubiquitin E3 ligase family and overexpressed in several solid malignancies including PCa. CUL4B has been suggested to be an oncogene through epigenetic repression of tumor suppressors. However, the link between CUL4B expression and cancer stem-like phenotype remains unclear. METHODS: Western blot analysis, sphere formation, and colony formation assays were used to examine the effect of CUL4B on cancer stem-like traits in PCa cells. Mechanically, bioinformatic analysis was utilized to evaluate whether BMI1 was a target of CUL4B. Moreover, real-time polymerase chain reaction, chromatin immunoprecipitation, and luciferase reporter assays were performed to identify microRNAs regulated by CUL4B. Finally, Western blot assay was used to validate the regulation of CUL4B, miR200b, and miR200c (miR200b/c) on the stem-like characteristics of PCa cells. RESULTS:CUL4B promotes PCa pluripotency-associated markers expression, sphere formation, and anchorage-independent growth ability in vitro. Mechanically, CUL4B upregulates BMI1 expression via epigenetically repressing miR200b/c expression. In addition, miR200b/c could partially reverse CUL4B-induced BMI1 and pluripotency-associated marker expression. CONCLUSIONS: Our study revealed that CUL4B regulates cancer stem-like traits of prostate cancer cells by targeting BMI1 via miR200b/c, which might give novel insight into how CUL4B promotes PCa progression through regulating cancer stem-like traits.
Authors: Hisham F Bahmad; Mohammad Jalloul; Joseph Azar; Maya M Moubarak; Tamara Abdul Samad; Deborah Mukherji; Mohamed Al-Sayegh; Wassim Abou-Kheir Journal: Front Genet Date: 2021-03-26 Impact factor: 4.599