Downregulation of Dicer, a component of the microRNA machinery, in bladder cancer
MOLECULAR MEDICINE REPORTS
Authors: Wu, Deyao; Tao, Jun; Xu, Bin; Li, Pengchao; Lu, Qiang; Zhang, Wei
Abstract
Dysregulation of microRNA metabolism has been observed in a variety of human cancers. In this study, we evaluated the expression of the enzymes of the machinery Dicer, Drosha and DGCR8, in transitional cell carcinomas (TCCs) of the urinary bladder. The expression of Dicer, Drosha and DGCR8 was analyzed using semi-quantitative RT-PCR in clinical specimens from normal bladder mucosa, TCCs and their normal adjacent tissues (NATs). Immunohistochemistry was performed to compare the expression of Dicer in normal, TCCs and NATs. Our study demonstrated that Dicer mRNA levels in TCCs were significantly lower compared to normal samples and NAT samples. The immunohistochemistry results revealed that Dicer protein levels in TCCs were significantly downregulated compared to normal bladder mucosa and NATs. Our data demonstrated that Dicer is significantly downregulated in TCCs compared to paired NAT samples and normal samples, suggesting that reduced expression of Dicer may play an important role in bladder cancer.
Splicing factors as regulators of miRNA biogenesis - links to human disease
SEMINARS IN CELL & DEVELOPMENTAL BIOLOGY
Authors: Ratnadiwakara, Madara; Mohenska, Monika; Anko, Minna-Liisa
Abstract
MicroRNAs ( miRNAs) are small non-coding RNAs that regulate gene expression post-transcriptionally by fine-tuning mRNA levels and translation during development and in adult tissues. miRNAs are transcribed as parts of longer precursors that undergo multiple processing steps before the mature miRNAs reach their target mRNAs in the cytoplasm. In addition to Drosha/DGCR8 and Dicer that are the essential components of the miRNA processing pathway, a range of other RNA binding proteins have recently been implicated in miRNA biogenesis. Among these, several well-known splicing factors have emerged as regulators of distinct miRNAs. In this review, we examine the mechanisms by which splicing factors regulate miRNA biogenesis. As both splicing factors and miRNAs play central roles in human disease biology we discuss implications of the links between splicing factors and miRNAs in human disease. (C) 2017 Elsevier Ltd. All rights reserved.