1. microRNA-155-5p initiates childhood acute lymphoblastic leukemia by regulating the IRF4/CDK6/CBL axis
- Author
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Yunpeng Dai, Ping Zhao, Guotao Guan, Qi Wang, Xiuli Li, Xiaojun Sun, and Liying Liu
- Subjects
Mice, Nude ,Apoptosis ,Pathology and Forensic Medicine ,Mice ,Ubiquitin ,Cell Line, Tumor ,hemic and lymphatic diseases ,microRNA ,Animals ,Humans ,Molecular Biology ,Childhood Acute Lymphoblastic Leukemia ,Cell Proliferation ,Reporter gene ,biology ,Kinase ,Cyclin-Dependent Kinase 6 ,Cell Biology ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,Ubiquitin ligase ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,Interferon Regulatory Factors ,biology.protein ,Cancer research ,Cyclin-dependent kinase 6 ,IRF4 - Abstract
Acute lymphoblastic leukemia (ALL) is a common malignancy in children. In this study, we aimed to explore putative mechanisms of microRNA-155-5p (miR-155-5p) involvement in childhood ALL (cALL) via interactions with casitas B-lineage lymphoma (CBL), interferon regulatory factor 4 (IRF4), and cyclin-dependent kinase 6 (CDK6). Bioinformatic analysis was performed initially to identify differentially expressed genes in cALL. The expression levels of miR-155-5p, CBL, IRF4, and CDK6 in peripheral blood lymphocytes from clinical ALL samples were determined using RT-qPCR and Western blot assays. A dual-luciferase reporter gene assay was used to ascertain a possible targeting relationship between miR-155-5p and CBL, CCK-8 assay and flow cytometry were used to measure cell activity and apoptosis of ALL cells. Co-IP was performed to investigate the interaction between CBL and IRF4 and the ubiquitination level of IRF4. Furthermore, in vivo validation was performed inducing xenograft tumor models with ALL cells in nude mice. As indicated by bioinformatic analysis, miR-155-5p and CDK6 were upregulated and CBL was downregulated in ALL. miR-155-5p was found to target CBL to inhibit CBL expression. miR-155-5p promoted the proliferation of ALL cells and inhibited their apoptosis by inhibiting the expression of CBL, which otherwise degraded IRF4 protein through ubiquitination, leading to inhibited CDK6 expression. Collectively, the results show that miR-155-5p can promote the development of cALL via the regulation on CBL-mediated IRF4/CDK6 axis. The authors explored the role of microRNA-155-5p (miR-155-5p) in childhood acute lymphoblastic leukemia (cALL). They found that miRNA-155-5p targets the E3 ubiquitin ligase CBL and inhibits its expression, reducing the ubiquitination and degradation of interferon regulatory factor 4, thus elevating expression of cyclin-dependent kinase 6. These findings suggest a basis for potential future therapeutic strategies for cALL.
- Published
- 2022
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