Abstract
Objectives: MicroRNAs of the miR-200 family are recognized as key inhibitors of epithelial-to-mesenchymal transition (EMT). However, there is limited data on the potential regulation of miR-200 family expression by long non-coding RNAs (lncRNAs) in RCC. Methods: We conducted a comprehensive literature and database search to identify lncRNAs that had been already functionally validated as regulators of any member of the miR-200 family. We analyzed the expression levels of the miR-200 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. Results: 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 miR-200 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 miR-200 family and 17 lncRNAs. In particular, three lncRNAs (MALAT1, OIP5-AS1, and LINC00467) showed a correlation with the expression of all members of the miR-200 family. Our results were at least partially confirmed in KIRC samples from the TCGA dataset. Conclusions: Our results suggest that the expression of the miR-200 family in RCC might be at least partially influenced by lncRNAs. Based on our cohort of samples, MALAT1, OIP5-AS1, and LINC00467 appear to be potentially important contributors to RCC development.