Correlation between serum microRNA-497 expression and invasion, metastasis and prognosis of colorectal cancer / 中国医师杂志

ABSTRACT

Objective:To investigate the correlation between microRNA-497 (miR-497) expression and invasion and metastasis and prognosis of colorectal cancer (CRC).Methods:The expression of miR-497 in 93 CRC patients (CRC group), 30 colorectal adenoma polyps (colorectal adenomatous polyp group) and 30 healthy patients (normal control group)were detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR); meanwhile, the content of serum carcinoembryonic antigen (CEA) was detected by chemiluminescence; After 3 years follow-up, the expression of miR-497 was measured again; the correlation between the expression of miR-497 and the clinicopathological characteristics and prognosis of CRC was analyzed.Results:The expression of miR-497 in CRC group was significantly lower than that at the end of postoperative treatment, adenomatous polyps group and normal control group ( P<0.01), and the content of CEA in CRC group was significantly higher than that at the end of postoperative treatment, adenomatous polyps group and normal control group ( P<0.01); At the end of postoperative treatment, the expression of serum miR-497 in CRC group was lower than that in normal control group ( P<0.05), and the content of serum CEA was higher than that in normal control group ( P<0.05). The diagnosis positive rate of serum miR497 expression in CRC group was significantly higher than that of serum CEA ( P<0.01), and they showed no correlation ( r=0.232, P>0.05). The pre-and post-operative serum miR-497 expression levels in the recurred and metastasis group were significantly lower than those in the no postoperative recurrence and metastasis group ( P<0.01). The preoperative expression of miR-497 was related to the differentiation degree of CRC, tumor node metastasis (TNM) stage, lymph node metastasis, distant metastasis and survival period ( P<0.01), but not with the age, sex, tumor size and location of the patients ( P>0.05). Cox multivariate analysis showed that tumor differentiation, TNM stage, preoperative miR-497 expression, lymph node metastasis and distant metastasis were all independent risk factors influencing prognosis of CRC patients ( P<0.05); The survival rate of 1, 2, 3 years in the miR-497 low expression group was lower than that in the miR-497 high expression group ( P<0.05). Conclusions:The preoperative low serum miR-497 expression levels are closely relative with invasion and metastasis and poor prognosis of CRC, and can be a prognostic indicator of CRC. The reduced postoperative serum miR-497 expression levels may be a predictor of the postoperative recurrence and metastasis of CRC.