Yang Yang,Guoying Zhang,Jian Li,Rui Gong,Yingbao Wang,Yang Qin,Qinrong Ping,Libing Hu
Background Increasing evidences have proved that long noncoding RNAs (lncRNAs) regulate the occurrence of bladder cancer (BC) and participate in various pathophysiology processes. However, little is unknown about the role of lncRNAs in drug resistance of BC cells. In this study, we explored the role of non-coding RNA activated by DNA damage (NORAD) in the gemcitabine (GEM) resistant of BC cells and explored its potential mechanism. Methods Real-time quantitative PCR (RT-qPCR) was used to detect the expression of NORAD and miR-155–5p of BC cells. Cell counting kit-8 (CCK-8) and Western blot were used to detect cell inhibition rate and the expression of WEE1 G2 checkpoint kinase (WEE1), P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1). Flow cytometry detected cell cycle and apoptosis . Dual luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay were used to confirm the targeting relationship between miR-155–5p, NORAD and WEE1. The xenograft model was used to observe the function of NORAD in vivo. immunohistochemistry (IHC) assay was used to detect the expression of WEE1, caspase-3 and Ki67 in tumor tissues. Results NORAD highly expressed in GEM-resistant BC cell lines . Knockdown of NORAD significantly inhibited the proliferation of T24/GEM cells, the expression of drug-resistant proteins P-gp and MRP1, inhibit the G0/G1 phase of cells, and induce cell apoptosis. Knockdown of NORAD reversed the promotion effect of miR-155–5p on WEE1 expression and promoted the sensitivity of T24/GEM cells to GEM. In vivo , knockdown of NORAD inhibited the tumor growth, and enhanced the GEM-sensitivity in mice. Conclusion These data highlight the potential of NORAD acts as a therapeutic target for BC GEM resistance. It revealed the vital roles of NORAD/miR-155–5p/WEE1 axis in GEM resistant BC cells, providing a novel therapeutic strategy for BC.
Background & aims Abnormal expression of long noncoding RNAs is strongly linked to metabolic dysfunction-associated steatotic liver disease (MASLD). However, the precise molecular mechanisms remain unclear. This study explores the roles of noncoding RNA activated by DNA damage (NORAD)/miR-511-3p/Rho-associated protein kinase 2 ( Rock2 ) axis and the NORAD/ROCK2 interaction in the development of MASLD. Methods In vitro and in vivo models of MASLD were created using high-fat diet-fed mice and free fatty acid (FFA)-treated hepatocytes. To examine the relationships between NORAD, miR-511-3p, and ROCK2, we employed bioinformatics, luciferase assays, RNA immunoprecipitation, and biotinylated NORAD pull-down assays. MASLD progression was assessed based on food intake, energy expenditure, insulin resistance, hepatic steatosis, inflammation, white fat growth, and liver fibrosis. Results NORAD and ROCK2 were upregulated, while miR-511-3p was downregulated in MASLD liver tissues and FFA-treated hepatocytes. Mechanistically, NORAD competitively interacted with miR-511-3p to modulate Rock2 mRNA expression, and directly stabilized ROCK2 protein by abrogating its ubiquitination degradation. Functionally, liver-specific knockdown of NORAD or overexpression of miR-511-3p significantly slowed MASLD progression. Overexpression of NORAD or ROCK2 partially reversed miR-511-3p-induced inhibition of MASLD. Additionally, ROCK2 knockdown attenuated NORAD-induced worsening of MASLD. Moreover, overexpressing NORAD or ROCK2 or interfering miR-511-3p influenced resmetirom treatment to suppress MASLD development. Finally, metabolic changes in liver driven by the NORAD/miR-511-3p/ Rock2 axis and NORAD/ROCK2 interaction also influenced white adipose growth, pancreatic β-cell dedifferentiation, and liver fibrosis. Conclusions The NORAD/miR-511-3p/ Rock2 axis and the NORAD/ROCK2 interaction play critical roles in MASLD progression, identifying potential therapeutic targets for its treatment.