miR-452-5p and miR-215-5p expression levels in colorectal cancer tissues and their relationship with clinicopathological features

The aim of the study was to investigate the expression levels of miR-452-5p and miR-215-5p in colorectal cancer tissues and their relationship with clinicopathological features. A total of 50 specimens of cancerous and adjacent normal tissues were collected from patients with colorectal cancer who underwent surgical resection at the Xingtai People's Hospital from March 2012 to February 2014. All specimens were confirmed by the Department of Pathology. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to measure the expression levels of miR-452-5p and miR-215-5p in cancerous and adjacent normal tissues. Moreover, the relationship of the expression levels of miR-452-5p and miR-215-5p with the clinicopathological features of patients with colorectal cancer was explored. The expression levels of both miR-452-5p and miR-215-5p in colorectal cancer tissues were significantly lower than those in adjacent normal tissues (P<0.05). miR-452-5p expression was related to tumor-node-metastasis (TNM) staging and differentiation degree in colorectal cancer tissues, and the expression of miR-215-5p was associated with TNM staging, lymph node metastasis and infiltration depth (P<0.05). The 5-year overall survival (OS) rate in the miR-452-5p high-expression group was significantly higher than that in the low-expression group (P<0.05). The 5-year OS rates in the miR-215-5p high- and low-expression groups were 53.57% (15/28) and 40.91% (9/22), respectively, indicating that the 5-year OS rate in the miR-215-5p high-expression group was significantly higher than that in the low-expression group. Cox proportional hazards regression model showed that TNM staging, lymph node metastasis, as well as miR-452-5p and miR-215-5p expression levels were independent risk factors affecting colorectal cancer prognosis (P<0.05), whereas the differentiation degree and infiltration depth were not (P>0.05). In conclusion, the expression levels of miR-452-5p and miR-215-5p were significantly downregulated in colorectal cancer tissues promoting the occurrence, progression, invasion and metastasis of colorectal cancer, which suggests that miR-452-5p and miR-215-5p could be used as prognostic indicators for patients with colorectal cancer.