Mutations in PBRM-1 and BAP-1 genes, and the expression of S100P have been related to survival in ICC. miR-31 seems also to play important regulatory functions in ICC and it directly regulates BAP-1 expression in lung cancer.
Using a bioinformatics approach, we identified miR-31 target mRNAs and independently confirmed them as direct targets in human and mouse lung cancer cell lines.
CSC significantly increased miR-31 expression and activated LOC554202 in normal respiratory epithelia and lung cancer cells; miR-31 and LOC554202 expression persisted following discontinuation of CSC exposure. miR-31 and LOC554202 expression levels were significantly elevated in lung cancer specimens relative to adjacent normal lung tissues.
As a direct downstream target of miR-31, SATB2 is a prominent transcription factor, and nuclear matrix binding protein implicated in many types of human diseases including lung cancer.
A survival curve was drawn according to the Kaplan-Meier method to evaluate the prognostic value of the circulating microRNA-31 expression levels for lung cancer.
However, high expression of circulating miR-31 did not significantly increase the risk of poor differentiation (pooled OR=1.39, 95% CI: 0.56-3.47) and LNM (pooled OR=3.46, 95% CI: 0.96-12.42) in lung cancer.
Moreover, the present data indicate that the interaction of miR-31 targets may be promising candidates as biomarkers for the diagnosis, prognosis and personalized therapy of lung cancer.
From the miRNAs, a logistic regression model was built on the basis of miR-31 and miR-210, both of which had the best prediction for lung cancer, producing an area under receiver operating characteristic curve of 0.83.
The enhanced expression of miR-31 has been observed in many human malignancies including lung cancer, and this microRNA regulates several aspects of oncogenesis.
Furthermore, combined quantification of miR-31 and miR-210 copy number by using digital PCR in sputum of the cases and controls provided 65.71 % sensitivity and 85.00 % specificity for lung cancer diagnosis.