Identification of miR-195-5p as a novel prognostic biomarker for colorectal cancer

Background: Recent evidence indicated that transcription patterns of microRNAs could be used as promising biomarkers for numerous cancers. It is stated that miR-195-5p could be used as a tumor suppressor in colorectal cancer (CRC). The purpose of the current work was to explore the transcription level of miR-195-5p and its clinical relevance in CRC patients.

Methods and results: We used quantitative real-time polymerase chain reaction (qRT-PCR) to assess the tumor tissue sample of 140 CRC cases compared with normal adjacent tissue for the transcription of miR-195-5p and the clinicopathological relevance was statistically evaluated. We showed that tumor tissue miR-195-5p transcription was statistically downregulated in patients with CRC (median expression value 0.23, range 0.03-6.62) compared to normal adjacent tissue (median expression value 0.98, range 0.092-29.6, p < 0.001). The median transcription of miR-195-5p divided the CRC patients into miR-195-5p low-transcription (miR-195-5p^low) and miR-195-5p high-transcription (miR-195-5p^high) groups. Furthermore, low miR-195-5p transcription level was statistically related with TNM stage, lymph node metastasis and tumor differentiation in CRC patients (all p-value < 0.05). Moreover, our results indicated that CRC cases with a decreased transcription level of miR-195-5p displayed a statistically shorter overall survival (OS) (p = 0.001) compared to higher miR-195-5p transcription.

Conclusion: In conclusion, the finding proposes that miR-195-5p might be a valuable biomarker and a prognostic factor for CRC in the future.