Aberrantly expressed microRNAs in bladder cancer and renal cell carcinoma

Abstract

Bladder cancer (BC) and renal cell carcinoma (RCC) are frequently diagnosed urinary tract cancers. Recently developed molecular-targeted therapies for RCC have shown remarkable therapeutic efficacy; however, no targeted therapeutics are currently approved for the treatment of BC, and few effective treatment options exist. Current studies have shown that small noncoding RNA molecules have major roles in cancer cells. MicroRNAs (miRNAs) are endogenous small noncoding RNA molecules that regulate protein-/nonprotein-coding RNAs in human cells. A large body of evidence suggests that aberrantly expressed miRNAs are deeply involved in the pathogenesis of human cancers. In this paper, we review recently published miRNA expression signatures of BC and RCC. We focus on downregulated or upregulated miRNAs in multiple signatures and discuss putative target genes of miRNAs. Comparisons of RCC and BC expression signatures revealed that the two types of cancer showed opposite expression patterns for miR-200 family miRNAs (i.e., miR-141/200c and miR-200a/200b/429). We discuss in silico analysis of genes targeted by miR-200 family miRNAs and the molecular mechanisms underlying BC and RCC.

The epigenetic landscape of renal cancer

“…As discussed above, E-cadherin is essential to maintain epithelial identity and localizes β-catenin to MET and mTOR pathways. miR-206 is frequently downregulated in ccRCC 196 and directly downregulates c-MET and BCL2 transcripts in lung and rhabdomyosarcoma tumours 205,206 , suggesting that this mechanism might contribute to tumour progression in RCC. Phosphatase and tensin homologue (PTEN) inhibits PI3K-mediated phosphorylation of AKT and subsequent activation of mTORC1.…”

“…Protein levels of VEGF are controlled by miR-206 and miR-106a-5p, which are frequently downregulated in ccRCC 196 . The VEGF receptor can also be upregulated if the levels of mi RNAs 206, 106-5a, 216b, 3065-5p, 335-5p or 3065-5p 196 are decreased.…”

“…Protein levels of VEGF are controlled by miR-206 and miR-106a-5p, which are frequently downregulated in ccRCC 196 . The VEGF receptor can also be upregulated if the levels of mi RNAs 206, 106-5a, 216b, 3065-5p, 335-5p or 3065-5p 196 are decreased. The dysregulation of multiple mi RNAs is a common hallmark of cancers, and is often associated with genome-wide methylation and chromatin pattern changes or mutations in miRNA-processing proteins 43,180,197 .…”

Potential therapeutic implications of miRNAs in osteosarcoma chemotherapy

“…[5][6][7][8] Recently, many researches show aberrant levels of miRNAs in various cancer cells. [9][10][11] In addition, plenty of reports demonstrate that miRNAs are involved in modulation cancer cell proliferation, metastasis, apoptosis, and autophagy. [12][13][14][15][16][17][18][19] Moreover, latest documents associate miRNAs with resistance to chemotherapy drugs in cancer including ostesoarcoma.…”

Regulation of HMGB3 by antitumor miR-205-5p inhibits cancer cell aggressiveness and is involved in prostate cancer pathogenesis

“…In contrast, downregulated antitumor miRNAs can lead to overexpression or activation of oncogenes. Discovery of microRNA (miRNA)-regulated genes improves our understanding RNA networks in cancer cells [9][10][11][12][13][14][15].…”