ABSTRACT
MicroRNAs (miRNAs) are involved in the progression of different types of cancers giving new hope for cancer treatment. The role and regulatory mechanism of microRNA187 (miR187) are largely unknown. In the present study, 74 patients with nonsmall cell lung cancer (NSCLC) were selected. Tumor tissues and matched normal tissues were collected for determining the expression level of miR187. Cell research was performed to detect the function of miR187. The expression level was measured and miR187 was found to be overexpressed in the NSCLC cell lines and tissues. Overexpression of miR187 promoted cell proliferation in the A549 and H1650 cell lines. Moreover, overexpression of miR187 also promoted cell migration and invasion. Polymerase I and transcript release factor (PTRF) was identified as a target of miR187. Overexpression of miR187 suppressed the expression of PTRF. Knockdown of PTRF promoted lung cancer cell invasion, and overexpression of PTRF had a negative effect on lung cancer cell invasion. The PTRF messenger RNA (mRNA) levels in cancer tissues were significantly lower than those in their adjacent normal lung tissues as determined by realtime PCR (RTPCR). The expression of the PTRF protein was significantly weaker than that in the adjacent normal lung tissues using immunohistochemical staining. The findings revealed that miR187 promotes cell growth and invasion by targeting PTRF and miR187 may be a new prognostic factor for NSCLC.
