Plasma miR-183-5p in colorectal cancer patients as potential predictive lymph node metastasis marker

Lymph node metastasis (LNM) is a point that often, treatment is not effective in colorectal cancer (CRC). Clinical and pathologic markers of prognosis help clinicians in selecting patients for adjuvant therapy after surgical resection in CRC. MiR-183-5p has been demonstrated to play as an oncogene in CRC, although its biological role still remains unclear. The aim of this study was to evaluate the expression of miR-183-5p in CRC and its potential relevance to clinicopathological characteristics as a prognostic biomarker.

In this case-control study, 33 CRC plasma samples at stage I-II-III, as well as plasma samples from 13 healthy controls, were collected. The relative expression levels of miR-183-5p in cancer and the normal samples were measured by quantitative real-time PCR. We analyzed their correlation with clinicopathological parameters and prognostic value.

Our results indicated that miR-183-5p was significantly overexpressed in CRC samples compared to healthy controls (P < 0.001) from a cutoff value of 3.9 with a sensitivity of 89% and a specificity of 91% and an AUC value of 0.74. Further analysis showed that a high plasma expression level of miR-183-5p was significantly associated with LNM and higher tumor/node/metastases stage (III) (P-value < 0.001).

In conclusion, the overexpression of miR-183-5p is highly related to advanced clinical stage, LNM and poor prognosis of CRC, indicating that miR-183-5p may serve as a predictive biomarker for the prognosis or the aggressiveness of CRC.