MicroRNA Expression Profiling in Clear Cell Renal Cell Carcinoma: Identification and Functional Validation of Key miRNAs

Abstract

ObjectiveThis study aims to profile dysregulated microRNA (miRNA) expression in clear cell renal cell carcinoma (ccRCC) and to identify key regulatory miRNAs in ccRCC.Methods and ResultsmiRNA expression profiles in nine pairs of ccRCC tumor samples at three different stages and the adjacent, non-tumorous tissues were investigated using miRNA arrays. Eleven miRNAs were identified to be commonly dysregulated, including three up-regulated (miR-487a, miR-491-3p and miR-452) and eight down-regulated (miR-125b, miR-142-3p, miR-199a-5p, miR-22, miR-299-3p, miR-29a, miR-429, and miR-532-5p) in tumor tissues as compared with adjacent normal tissues. The 11 miRNAs and their predicted target genes were analyzed by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and three key miRNAs (miR-199a-5p, miR-22 and miR-429) were identified by microRNA-gene network analysis. Dysregulation of the three key miRNAs were further validated in another cohort of 15 ccRCC samples, and the human kidney carcinoma cell line 786-O, as compared with five normal kidney samples. Further investigation showed that over-expression of miR-199a-5p significantly inhibited the invasion ability of 786-O cells. Luciferase reporter assays indicated that miR-199a-5p regulated expression of TGFBR1 and JunB by directly interacting with their 3’ untranslated regions. Transfection of miR-199a-5p successfully suppressed expression of TGFBR1 and JunB in the human embryonic kidney 293T cells, further confirming the direct regulation of miR-199a-5p on these two genes.ConclusionsThis study identified 11 commonly dysregulated miRNAs in ccRCC, three of which (miR-199a-5p, miR-22 and miR-429) may represent key miRNAs involved in the pathogenesis of ccRCC. Further studies suggested that miR-199a-5p plays an important role in inhibition of cell invasion of ccRCC cells by suppressing expression of TGFBR1 and JunB.

Aberrantly expressed microRNAs in bladder cancer and renal cell carcinoma

“…52,53 miRNA expression signatures of RCC We also reviewed six recently published miRNA expression signatures comparing RCC and normal kidney tissue using clinical specimens (Table 3). [18][19][20][21][22][23] Two signatures were constructed from deep sequencing and the other four signatures were constructed from microarrays. Commonly downregulated miRNAs or upregulated miRNAs in multiple signatures are listed in Table 4, sorted according to the number of signatures.…”

“…In this review, we summarize aberrantly expressed miRNAs based on current BC and RCC miRNA signatures. [11][12][13][14][15][16][17][18][19][20][21][22][23] We discuss the dysregulated expression of the miR-200 family and miR-200 family target genes in BC and RCC.…”

miR-125b is associated with renal cell carcinoma cell migration, invasion and apoptosis

“…The expression of miR-125b has been revealed to be deregulated in a number of types of cancer, including gastric cancer (16), non-small-cell lung cancer (NSCLC) (19) and osteosarcoma (12). Numerous previous studies about gene microarray in RCC revealed that miR-125b was downregulated in ccRCC tissues (20)(21)(22). However, another study identified that miR-125b was upregulated in ccRCC by performing ISH (17).…”

Effects of a 28-day dietary co-exposure to melamine and cyanuric acid on the levels of serum microRNAs in male and female Fisher 344 rats

“…miR-22 was found down-regulated in clear cell renal cell carcinoma (RCR) samples when compared to adjacent non-tumorous samples (He et al , 2015). The expression of miR-128 was reported also as down-regulated in the kidneys of patients with progressive versus stable chronic kidney disease (Rudnicki et al , 2016).…”