Cancer and MicroRNA as a Diagnostic and Therapeutic Marker

Abstract

MicroRNAs（miRNAs）are non-coding small RNAs that regulate cell proliferation and functions by interfering with the translation of target mRNAs. Altered expression of miRNAs is known to induce various human malignancies. We recently reported that miR-205 might be a specific marker miRNA of both normal and malignant squamous epithelia, while miR-21 might be a putative oncogenic miRNA in human head and neck squamous cell carcinoma（HNSCC），by miRNA microarray analysis. We next confirmed that altered expression of miR-200c and miR-27b directly regulated by hepatocyte growth factor（HGF）might contribute enhanced progressive and invasive characteristics（such as epithelial mesenchymal transition（EMT））of HNSCC by regulating the translation of HGF-induced functional molecules. We also found that the expression of miR-182-5p depended on the cancer grade（Gleason score（GS））even in same Gleason’s pattern（GP）4 prostate cancer, and reported that the expression of miRNA associated with Gleason’s grading system may contribute to more accurate preoperative cancer risk evaluation. These results suggested the significance of miRNAs as diagnositic, prognostic and therapeutic markers. In this paper, we review the relation of cancer with miRNA expression, and discuss the possibility of miRNAs as histopathological diagnostic, prognostic and therapeutic markers.