MiRNAs as molecular biomarkers in stage II egyptian colorectal cancer patients.

AIM: To assess the role of aberrant miRNAs expressions in stage II CRC patients from Egypt.

METHODS: Tumor tissue samples were obtained from 124 CRC stage II patients compared to 100 healthy controls for assessing miRNAs expression using; 1) a cataloged 84-miRNAs PCR array panel, and 2) another five miRNAs (miR-21, miR-137, miR-145, miR-320 and miR-498) that have been reported in previous studies to have a role in CRC, by quantitative real time PCR (qPCR). The results were correlated to patients' characteristics, response to treatment and survival.

RESULTS: There were 17 out of 84 miRNAs differentially expressed in the CRC patients. Twenty six miRNAs were significantly differentially expressed in the female CRC patients, while 16 miRNAs were significantly differentially expressed in the male CRC patients. Only, five miRNAs (miR-21, Let-7a-5p, miR-100-5p, miR-200c-3p and miR-23b-3p) were significantly common deregulated in CRC patients regardless gender. miR-21 was overexpressed in 48.4% of the patients and it was significantly downregulated in females and over expressed in males. In univariate analysis; performance status, over-expression of miR-21 and miR-498 and reduced miR-137, miR-145, and miR-320 associated significantly with reduced DFS and OS whereas in multivariate analysis; miR-498 and miR-320 were independent prognostic factors for DFS and miR-21 was independent prognostic factors for OS.

CONCLUSION: miRNAs expression differs significantly between male and female stage II CRC patients, miR-21, Let-7a-5p, miR-100-5p, miR-200c-3p and miR-23b-3p could be used as common diagnostic biomarkers for CRC. On the other hand, a three miRNAs panel (miR-21, miR-498 and miR-320) can predict recurrence and survival in those patients.