Small molecules targeting bromodomains of BET proteins possess strong anti-tumor activities and have emerged as potential therapeutics for cancer. However, the underlying mechanisms for the anti-proliferative activity of these inhibitors are still not fully characterized. In this study, we demonstrated that BET inhibitor JQ1 suppressed the proliferation and invasiveness of gastric cancer cells by inducing cellular senescence. Depletion of BRD4, which was overexpressed in gastric cancer tissues, but not other BET proteins recapitulated JQ1-induced cellular senescence with increased cellular SA-β-Gal activity and elevated p21 levels. In addition, we showed that the levels of p21 were regulated at the post-transcriptional level by BRD4-dependent expression of miR-106b-5p, which targets the 3'-UTR of p21 mRNA. Overexpression of miR-106b-5p prevented JQ1-induced p21 expression and BRD4 inhibition-associated cellular senescence, whereas miR-106b-5p inhibitor up-regulated p21 and induced cellular senescence. Finally, we demonstrated that inhibition of E2F suppressed the binding of BRD4 to the promoter of miR-106b-5p and inhibited its transcription, leading to the increased p21 levels and cellular senescence in gastric cancer cells. Our results reveal a novel mechanism by which BRD4 regulates cancer cell proliferation by modulating the cellular senescence through E2F/miR-106b-5p/p21 axis and provide new insights into using BET inhibitors as potential anticancer drugs.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5833665 | PMC |
http://dx.doi.org/10.1038/s41419-017-0181-6 | DOI Listing |
ACS Biomater Sci Eng
January 2025
Department of Gastrointestinal Surgery, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China.
Perianal fistulas (PAFs) are a severe complication of Crohn's disease that significantly impact patient prognosis and quality of life. While stem-cell-based strategies have been widely applied for PAF treatment, their efficacy remains limited. Our study introduces an injectable, temperature-controlled decellularized adipose tissue-alginate hydrogel loaded with dental pulp mesenchymal stem cells (DPMSCs) for in vivo fistula treatment.
View Article and Find Full Text PDFCancer Res
January 2025
Oregon Health & Science University, Portland, OR, United States.
Senescence is a non-proliferative, survival state that cancer cells can enter to escape therapy. In addition to soluble factors, senescence cells secrete extracellular vesicles (EVs), which are important mediators of intercellular communication. To explore the role of senescent cell-derived EVs (senEVs) in inflammatory responses to senescence, we developed an engraftment-based senescence model in wild-type mice and genetically blocked senEV release in vivo, without significantly affecting soluble mediators.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Orthopedic Surgery, Changzheng Hospital, Naval Medical University, Shanghai, 200003, P. R. China.
Nucleus pulposus cell (NPC) senescence contributes to intervertebral disc degeneration (IVDD). However, the underlying molecular mechanisms are not fully understood. In this study, it is demonstrated that angiotensin-converting enzyme 2 (ACE2) counteracted the aging of NPCs and IVDD at the cellular and physiological levels.
View Article and Find Full Text PDFMol Cell Biol
January 2025
Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, Maryland, USA.
Cellular senescence is a complex biological response to sublethal damage. The RNA-binding protein HNRNPK was previously found to decrease prominently during senescence in human diploid fibroblasts. Here, analysis of the mechanisms leading to reduced HNRNPK abundance revealed that in cells undergoing senescence, mRNA levels declined transcriptionally and full-length HNRNPK protein was progressively lost, while the abundance of a truncated HNRNPK increased.
View Article and Find Full Text PDFCalcineurin inhibitors (CNIs) are indispensable immunosuppressants for transplant recipients and patients with autoimmune diseases, but chronic use causes nephrotoxicity, including kidney fibrosis. Why inhibiting calcineurin, a serine/threonine phosphatase, causes kidney fibrosis remains unknown. We performed single-nucleus RNA sequencing of the kidney from a chronic CNI nephrotoxicity mouse model and found an increased proportion of injured proximal tubule cells, which exhibited altered expression of genes associated with oxidative phosphorylation, cellular senescence and fibrosis.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!