Erratum to: "Fer exacerbates renal fibrosis and can be targeted by miR-29c-3p".

[This corrects the article DOI: 10.1515/med-2021-0319.].

Fer exacerbates renal fibrosis and can be targeted by miR-29c-3p.

AIM: Renal fibrosis (RF) is a common clinical condition leading to irreversible renal function loss. Tyrosine kinase proteins and microRNAs (miRs) are associated with pathogenesis and we aim to investigate the role of Fer and its partner miR(s) in RF. METHOD: In silico reproduction of Mouse Kidney FibrOmics browser was performed to identify potential miR(s) and target gene(s). In vivo validation was performed in C57BL/6 mice with unilateral ureteral obstruction (UUO). In vitro validation was performed in rat kidney fibroblast NRK-49F cells. Mimics and inhibitors of miR-29c-3p were constructed. The target gene Fer was monitored by RT-PCR and western blotting. The levels of interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α in serum and media were measured by ELISA. RESULTS: The Fer expression and protein level were gradually increased during 14 days of UUO modeling. miR-29c-3p expression was strongly correlated with that of Fer. In vivo validation showed increased expressions of fibrosis-associated genes and increased phospoho-Smad3 level in the UUO model. Fer-knockdown (KD) significantly decreased expressions of fibrosis-associated genes. Pharmaceutical inhibition of Fer showed similar effects to miR-29c-3p, and miR inhibition showed a significant decrease of excretion of inflammatory factors. CONCLUSION: Dysregulation of miR-29c-3p and Fer plays a role in RF. Pharmaceutical or genetic inhibition of Fer may serve as the potential treatment for RF.

microRNA let-7i-5p aggravates kidney fibrosis via targeting GALNT1.

Renal fibrosis poses critical health problem. We aimed to investigate role of let-7i-5p in renal fibrosis. In silico reproduction of Mouse Kidney FibrOmics browser was used to identify potential target of let-7i-5p. In vivo validation was conducted in C57BL/6 mice with unilateral ureteral obstruction (UUO) and folic acid (FA) induction. In vitro validation was performed in transforming growth factor (TGF)-ß1-treated HK-2 cells. Mimics and inhibitors of let-7i-5p, and target gene polypeptide N-acetylgalactosaminyltransferase 1 (GALNT1) were monitored by RT-PCR and Western blotting. Fibrosis markers, injury markers, and house-keeping genes were evaluated. Levels of interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α in serum and media were measured by ELISA. In silico analysis showed gradual increase of let-7i-5p and decrease of GALNT1 over time and the combination was validated both in mouse and human miR-gene target prediction databases. Expression of GALNT1 decreased while expression of let-7i-5p increased in renal tissues of both UUO and FA mice. Serum IL-6, IL-1ß, and TNF-α levels were elevated in vivo. In vitro models revealed negative correlation between expression levels of let-7i-5p and GALNT1. Overexpression of let-7i-5p inhibited GALNT1 expression and reduced release of inflammatory factors. In conclusion, overexpression of GALNT1 may combat the inflammation induced by let-7i-5p.

circPRRC2A promotes angiogenesis and metastasis through epithelial-mesenchymal transition and upregulates TRPM3 in renal cell carcinoma.

Background: Circular RNAs (circRNAs) have been identified as essential regulators in a plethora of cancers. Nonetheless, the mechanistic functions of circRNAs in Renal Cell Carcinoma (RCC) remain largely unknown. Methods: In this study, we aimed to identify novel circRNAs that regulate RCC epithelial-mesenchymal transition (EMT), and to subsequently determine their regulatory mechanisms and clinical significance. Results: circPRRC2A was identified by circRNA microarray and validated by qRT-PCR. The role of circPRRC2A in RCC metastasis was evaluated both in vitro and in vivo. We found that increased expression of circPRRC2A is positively associated with advanced clinical stage and worse survivorship in RCC patients. Mechanistically, our results indicate that circPRRC2A prevents the degradation of TRPM3, a tissue-specific oncogene, mRNA by sponging miR-514a-5p and miR-6776-5p. Moreover, circPRRC2A promotes tumor EMT and aggressiveness in patients with RCC. Conclusions: These findings infer the exciting possibility that circPRRC2A may be exploited as a therapeutic and prognostic target for RCC patients.

Overexpression of CKAP4 is Associated with Poor Prognosis in Clear Cell Renal Cell Carcinoma and Functions via Cyclin B Signaling.

Aim: We aimed to study the role of CKAP4 in clear cell renal cell carcinoma (ccRCC), which is not reported previously. Method: In silico exploration and validation using immunohistochemistry in ccRCC samples were used to identify the impact of CKAP4 expression on clinicopathological parameters. In vitro and in vivo studies were carried out to recapitulate the role of CKAP4 in ccRCC cell lines and animal models. Results: Overexpression of CKAP4 occurred in 5% of ccRCC patients, who had significantly worsened prognosis. Increased CKAP4 expression was significantly associated with TNM staging and Fuhrman grade. Pathway analysis for genes coexpressed with CKAP4 in ccRCC unanimously revealed significant cell cycle progression at G2/M phase. Expressions of CCNB1 and CCNB2 were correlated with CKAP4 expression. Genetic upregulation of CKAP4 significantly increased proliferation, cell invasion and migration in ccRCC cell lines, and vice versa for CKAP4 silencing. CKAP4 silencing also significantly increased cell population at G2/M phase, while not influencing cell apoptosis. Silencing or upregulation of CKAP4 resulted in decreased or increased CCNB1/2 expressions, respectively. CCNB1/CDK1 inhibitor significantly inhibited colony formation ability and in vivo tumor growth of RCC cells with CKAP4 overexpression. Conclusion: Upregulation of CKAP4 was associated with worsened characteristics of ccRCC. CKAP4 was related with CCNB signaling in ccRCC, which supported a role for CCNB/CDK inhibitor for ccRCC with such genotype.

Genetic alteration in phosphofructokinase family promotes growth of muscle-invasive bladder cancer.

AIMS: Metabolic alterations in cancer, including bladder cancer, have been addressed in recent years. We aimed to study the role of phosphofructokinase (PFK) in muscle-invasive bladder cancer (MIBC). METHOD: By in silico analysis of the bladder cancer data from the Cancer Genome Atlas (TCGA) database using the cBioPortal platform, we studied genetic alteration of genes within the PFK family (PFKL, PFKM, PFKP, PFKFB1, PFKFB2, PFKFB3, and PFKFB4). In vitro studies were carried out using the PFK inhibitor 2,5-anhydro-D-glucitol-6-phosphate. RESULTS: Genetic alterations of PFK family genes were observed in ~44% of MIBC cases in TCGA. The main alterations were amplification and upregulation. Patients with altered PFK gene status were more likely to have a history of noninvasive bladder cancer. Altered PFK status was not associated with survival or disease relapse. Use of the PFK inhibitor significantly decreased the level of glycolysis and inhibited the growth and invasion of bladder cancer cells. CONCLUSIONS: PFKs were critical genes in charge of glycolysis and were upregulated in bladder cancer. Targeting this pathway could inhibit cell growth in bladder cancer.