Investigating the Relationship Between Long Non-Coding RNAs and miR-200 Family Expression in Clear Cell Renal Cell Carcinoma

<b>Objectives:</b> MicroRNAs of the <i>miR-200</i> family are recognized as key inhibitors of epithelial-to-mesenchymal transition (EMT). However, there is limited data on the potential regulation of <i>miR-200</i> family expression by long non-coding RNAs (lncRNAs) in RCC. <b>Methods:</b> We conducted a comprehensive literature and database search to identify lncRNAs that had been already functionally validated as regulators of any member of the <i>miR-200</i> family. We analyzed the expression levels of the <i>miR-200</i> family and the identified lncRNAs by qPCR. The study included 42 samples of carcinoma and non-carcinoma tissue from 25 RCC patients. In addition, we used RNA sequencing data from The Cancer Genome Atlas (TCGA), encompassing 511 kidney RCC (KIRC) samples, to further analyze the expression of miRNAs and lncRNAs. <b>Results:</b> We identified 127 lncRNAs with confirmed regulatory functions, 31 of which were validated in our samples. The majority of lncRNAs, along with all members of the <i>miR-200</i> family, showed consistent downregulation in carcinoma tissues compared to non-carcinoma tissues. We observed a significant correlation between the expression of at least one member of the <i>miR-200</i> family and 17 lncRNAs. In particular, three lncRNAs (<i>MALAT1</i>, <i>OIP5-AS1</i>, and <i>LINC00467)</i> showed a correlation with the expression of all members of the <i>miR-200</i> family. Our results were at least partially confirmed in KIRC samples from the TCGA dataset. <b>Conclusions:</b> Our results suggest that the expression of the <i>miR-200</i> family in RCC might be at least partially influenced by lncRNAs. Based on our cohort of samples, <i>MALAT1</i>, <i>OIP5-AS1</i>, and <i>LINC00467</i> appear to be potentially important contributors to RCC development.