To investigate the expression of microRNA (miRNA)-381-3p in colon cancer tissues and analyze its relationship with postoperative recurrence.

This was a retrospective study. Clinical data of 156 colon cancer patients who underwent surgery and had preserved colon cancer tissues and adjacent tissues in wax blocks from December 2021 to May 2024 were collected. The expression of miR-381-3p was detected by real-time fluorescence quantitative PCR. Independent sample t test and paired sample t test were used to compare the relative expression levels of miR-381-3p between groups and within groups. Chi-square test or Fisher's exact probability method was used to compare count data. Multivariate Logistic regression analysis was used to analyze the influencing factors of postoperative recurrence. The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of miR-381-3p for recurrence.

The relative expression level of miR-381-3p in cancer tissues was significantly lower than that in adjacent tissues (P<0.05). The relative expression level of miR-381-3p in cancer tissues of the recurrence group was lower than that of the non-recurrence group. The proportions of patients with lymph node metastasis, low differentiation of tissue, and TNM stage of Ⅲ were higher than those of the non-recurrence group (P<0.05). Multivariate Logistic regression model analysis showed that tissue differentiation and the relative expression level of miR-381-3p in cancer tissues were the influencing factors of postoperative recurrence (P<0.05). The ROC curve showed that the area under the curve (AUC) of miR-381-3p relative expression level for predicting postoperative recurrence was 0.907 (95%CI: 0.858~0.955), with a specificity of 83.3% and a sensitivity of 87.0%.

miR-381-3p is lowly expressed in colon cancer tissues. Its expression level is an independent risk factor for predicting postoperative recurrence. The AUC is 0.907, which has a high predictive value.