摘要目的:探讨结直肠癌(CRC)患者血清microRNA-497(miR-497)表达量与CRC侵袭转移及预后的关系。方法:实时荧光定量PCR(qRT-PCR)检测93例CRC患者术前及术后、30例结直肠腺瘤息肉患者及30位健康者血清miR-497表达量，同时化学发光法检测血清癌胚抗原(CEA)含量；随访CRC患者术后3年预后，复测血清miR-497表达量；分析术前血清miR-497表达量与CRC临床病理特征及预后的关系。结果:CRC组术前血清miR-497表达量显著低于其术后治疗结束时、腺瘤息肉组和正常对照组( P<0.01)，CEA含量显著高于术后治疗结束时、结直肠腺瘤息肉组和正常对照组( P<0.01)；结直肠癌组术后治疗结束时血清miR-497表达量低于正常对照组( P<0.05)，血清CEA含量高于术后正常对照组( P<0.05)；CRC组术前血清miR-497诊断阳性率显著高于血清CEA( P<0.01)；复发转移组术前及术后血清miR-497表达量均显著低于无复发转移组( P<0.01)；术前血清miR-497表达量与CRC分化程度、TNM分期、是否淋巴结转移、是否远处转移、生存期长短有关( P<0.01)，而与患者年龄、性别、肿瘤大小及部位均无相关性( P>0.05)。Cox多因素分析显示肿瘤分化程度、TNM分期、术前血清miR-497表达量、淋巴结转移及远处转移均是影响CRC患者预后的独立危险因素( P<0.05)；血清miR-497低表达量组1、2、3年生存率低于血清miR-497高表达量组( P<0.05)。 结论:术前血清miR-497低表达与CRC侵袭转移、不良预后密切相关，可成为其预后评价指标；术后血清miR-497表达量降低对CRC术后复发转移有一定预测价值。

abstractsObjective: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.