bims-lorfki Biomed News
on Long non-coding RNA functions in the kidney
Issue of 2021‒05‒02
four papers selected by
Nikita Dewani
Max Delbrück Centre for Molecular Medicine

  1. Cell Signal. 2021 Apr 23. pii: S0898-6568(21)00102-9. [Epub ahead of print] 110013
      Clear cell renal cell carcinoma (ccRCC) is a common subtype of renal cell carcinoma (RCC) and causes many deaths. Numerous medical studies have suggested that long noncoding RNAs (lncRNAs) exert their biological functions on ccRCC. Herein, functions of lncRNA SNHG16 in ccRCC cells and the mechanism mediated by SNHG16 were investigated. The expression levels of SNHG16 and its downstream genes in ccRCC cells and RCC tissues were examined utilizing reverse transcription quantitative polymerase chain reaction analyses. Cell counting kit-8 and 5-Ethynyl-2'-deoxyuridine assays were performed to evaluate the proliferation of ccRCC cells, and flow cytometry analyses were employed to determine the apoptosis of ccRCC cells. Western blot analysis was applied to examine protein levels associated with cell proliferation and apoptosis. The combination between SNHG16 and miRNA as well as miRNA and its target gene were explored by luciferase reporter, RNA pull down, and RNA immunoprecipitation assays. The significant upregulation of SNHG16 was observed in RCC tissues and ccRCC cells. SNHG16 downregulation inhibited the proliferation and promoted the apoptosis of ccRCC cells. In addition, SNHG16 served as a competing endogenous RNA for miR-1301-3p, and STARD9 was a target gene of miR-1301-3p in ccRCC cells. SNHG16 upregulated STARD9 expression by binding with miR-1301-3p in ccRCC cells. Rescue assays validated that SNHG16 promoted ccRCC cell promotion and induced ccRCC cell apoptosis by upregulating STARD9 expression. In conclusions, SNHG16 promotes ccRCC cell proliferation and suppresses ccRCC cell apoptosis via interaction with miR-1301-3p to upregulate STARD9 expression in ccRCC cells.
    Keywords:  Renal cell carcinoma; SNHG16; STARD9; miR-1301-3p
  2. Diabetes Metab Syndr Obes. 2021 ;14 1741-1750
      Background: Diabetic nephropathy (DN), as a complication of diabetes, is a leading cause of mortality in diabetic patients. It has been reported that lncRNA PVT1 (PVT1) could accelerate the progression of DN by promoting ECM accumulation and increasing the expression of fibronectin 1 (FN1). However, the underlying mechanism of PVT1 on DN remains unknown.Methods: To study the effect of PVT1 on DN, mice were injected 50 mg/kg STZ to build the DN models. Mesangial cells (MCs) were induced by high glucose as in vitro model of DN. The expression level of PVT1, miR-325-3 and Snail1 was assessed by qRT-PCR and Western blot. Luciferase reporter assay, RNA pull-down and RIP were used to explore the interaction among PVT1, miR-325-3 and Snail1.
    Results: In in vivo and in vitro DN models, the expression of PVT1 was upregulated. High glucose (HG) induced cell viability, oxidative stress, fibrosis and inflammation in MCs, which were reversed in the PVT1-KD MCs. The level of miR-325-3p was also increased in in vivo and in vitro experiments. Additionally, PVT1 can directly bind to miR-325-3p. Finally, Snail1 was a direct target of miR-325-3p.
    Conclusion: PVT1 inhibits viability, oxidative stress, fibrosis, and inflammation in DN via miR-325-3p/Snail1 axis.
    Keywords:  Snail1; diabetic nephropathy; lncRNA PVT1; miR-325-3p
  3. Noncoding RNA. 2021 Apr 10. pii: 25. [Epub ahead of print]7(2):
      Long non-coding RNAs (lncRNAs) can be specifically expressed in different tissues and cancers. By controlling the gene expression at the transcriptional and translational levels, lncRNAs have been reported to be involved in tumor growth and metastasis. Recent data demonstrated that multiple lncRNAs have a crucial role in renal cell carcinoma (RCC) progression-the most common malignant urogenital tumor. In the present study, we found a trend towards increased PROX1 antisense RNA 1 (PROX1-AS1) expression in RCC specimens compared to non-tumoral margins. Next, we found a positive correlation between PROX1-AS1 expression and the occurrence of distant and lymph node metastasis, higher tumor stage (pT1 vs. pT2 vs. pT3-T4) and high-grade (G1/G2 vs. G3/G4) clear RCC. Furthermore, global demethylation in RCC-derived cell lines (769-P and A498) and human embryonic kidney 293 (HEK293) cells induced a significant increase of PROX1-AS1 expression level, with the most remarkable change in HEK293 cells. In line with this evidence, bisulfite sequencing analysis confirmed the specific demethylation of bioinformatically selected CpG islands on the PROX1-AS1 promoter sequence in the HEK293 cell line but not in the tumor cells. Additionally, the human specimen analysis showed the hemimethylated state of CG dinucleotides in non-tumor kidney tissues, whereas the tumor samples presented the complete, partial, or no demethylation of CpG-islands. In conclusion, our study indicated that PROX1-AS1 could be associated with RCC progression, and further investigations may define its role as a new diagnostic marker and therapeutic target.
    Keywords:  PROX1-AS1; human specimens; non-coding RNA; renal cell carcinoma
  4. Exp Physiol. 2021 Apr 29.
      NEW FINDINGS: What is the central question of this study? Diabetic nephropathy (DN) is a severe diabetic complication correlated to higher mortality rate in diabetic patients. Renal tubular injury participates in the pathogenesis of DN. We aimed to uncover the biological function of NEAT1/miR-150-5p/Drp1 axis in an in vitro model of DN and elaborate the potential mechanisms. What is the main finding and its importance? NEAT1 facilitated HG-induced damage in HK-2 cells by reducing mitophagy via miR-150-5p/Drp1 axis, which sheds light on DN pathogenesis and discovers a potential treatment for DN.ABSTRACT: Diabetic nephropathy (DN) is a severe diabetic complication with a high mortality rate in diabetic patients. Renal tubular injury is involved in the pathogenesis of DN. In this study, we aimed to uncover the regulatory roles of NEAT1/miR-150-5p/Drp1 axis in an in vitro model of DN and its possible mechanisms. HG-challenged HK-2 cells were used as an in vitro DN model. NEAT1, miR-150-5p, and Drp1 levels were assessed by RT-qPCR. Cell viability was determined by MTT assay. MitoSOX red and JC-1 were used to evaluate intra-cellular ROS production and mitochondrial membrane potential (MMP), respectively. LDH release and SOD activity were assessed by commercial kits. The protein levels of Drp1, p62, Beclin-1 and BNIP3 were determined by Western blotting. The interaction between NEAT1 (Drp1) and miR-150-5p was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our results showed that NEAT1 and Drp1 levels were up-regulated, while miR-150-5p level was down-regulated in HK-2 cells in response to HG. Knockdown of NEAT1 or Drp1 inhibited excessive ROS production and LDH release, increased cell viability, MMP, SOD activity and enhanced mitophagy in HG-challenged HK-2 cells. However, inhibition of miR-150-5p resulted in the opposite results. Mechanistically, NEAT1 sponged miR-150-5p to increase Drp1 level. Moreover, silencing of NEAT1 or Drp1 could counteract miR-150-5p inhibition-induced deleterious effects. Collectively, our findings indicate that NEAT1 facilitates HG-induced damage in HK-2 cells by suppressing mitophagy via miR-150-5p/Drp1 axis, which sheds light on a novel mechanism of DN. This article is protected by copyright. All rights reserved.
    Keywords:  Drp1; NEAT1; diabetic nephropathy; miR-150-5p; mitophagy; renal tubular injury