关键词: miR-21, miR-135a, 胃癌, 化疗, 复发, 转移

Abstract: Objective To investigate the predictive value of serum miR-21 and miR-135a expression in the recurrence and metastasis of gastric cancer patients after chemotherapy. Methods A total of 100 gastric cancer patients（gastric cancer group） who underwent chemotherapy were enrolled,and 50 healthy subjects were enrolled as control group. The clinical data of all the patients were collected. Follow-up started 1 month after chemotherapy,and the follow-up time was 24 months. The relative expression levels of serum miR-21 and miR-135a in control subjects and gastric cancer patients before chemotherapy and at 3,8,13,18,and 24 months after chemotherapy were determined. Receiver operating characteristic（ROC） curve was used to evaluate the efficiency of miR-21 and miR-135a in judging the prognosis of gastric cancer. Results Compared with control group,the relative expression of miR-21 in gastric cancer group before chemotherapy increased（P<0.05）,and the relative expression of miR-135a decreased（P<0.05）. The relative expression levels of serum miR-21 and miR-135a before chemotherapy were related to lymph node metastasis,differentiation degree and the depth of invasion in patients with gastric cancer（P<0.05）,but they were not related to age,sex,TNM stage and the presence or absence of distant metastasis（P>0.05）. The 3 cases of 100 gastric cancer patients were lost to follow-up,and 66 cases（68%） had recurrence or metastasis. The relative expression of serum miR-21 in patients with recurrence or metastasis after chemotherapy increased with the extension of follow-up time（P<0.05）,and the relative expression of serum miR-135a decreased with the extension of follow-up time（P<0.05）. ROC curve analysis results showed that the areas under curves（AUC） of miR-21 and miR-135a single determinations to judge the poor prognosis of gastric cancer were 0.789 and 0.826,respectively. Taking both positive results as combined determination positive,and taking both negative results as combined determination negative,the sensitivity and specificity of the combined determination of miR-21 and miR-135a in judging the prognosis of gastric cancer were 91.2% and 67.8%,respectively. Conclusions The expressions of miR-21 and miR-135a in serum of patients with gastric cancer are abnormal,and the expression level is closely related to lymph node metastasis,the degree of differentiation and the depth of invasion. The combined determination of serum miR-21 and miR-135a has a value in judging the recurrence or metastasis of gastric cancer after chemotherapy.

Key words: MiR-21, MiR-135a, Gastric cancer, Chemotherapy, Recurrence, Metastasis