Abstract: Objective To investigate the relationship between the expression of miR-429, miR-200C and prognosis in patients with nasopharyngeal carcinoma. Methods 80 patients with nasopharyngeal carcinoma who received treatment between January 2016 and May 2017 were selected Tissue puncture samples were subjected to qRT-PCR detection to analyze the offset expression of miR-429 and miR-200C, and three treatments were performed. The Efficacy will be evaluated in the coming months. After discharge from the hospital, follow-up was conducted by telephone and outpatient follow-up, and the survival time of the patient was recorded. Results The relative expression levels of miR-429 and miR-200C in patients with different pathological stages, T stages, N stages and clinical stages were statistically significantly different, and the expression levels decreased with the increase of severity(P<0.05). After three months of treatment, the overall effective rate of 80 patients was 100%, of which 71 were CR(88.75%)and 9 were PR(11.25%). Fifty-five patients with death, recurrence or metastasis belonged to the poor prognosis group, and 18 patients with tumor-free survival belonged to the good prognosis group. The relative expression levels of miR-429 and miR-200C in the good prognosis group were higher than those in the poor prognosis group(P<0.05). The relative expression of miR-429 has a predictive cut-off value of 1.36 for the poor prognosis of nasopharyngeal carcinoma. The AUC was 0.723, 95% CI of 0.547 to 0.898, sensitivity of 82.15%, and the specificity was 81.72%; relative expression of miR-200C The predictive cut-off value of poor prognosis for nasopharyngeal carcinoma was 0.53, the AUC was 0.713, 95%CI was 0.562-0.865, the sensitivity was 82.01%, and the specificity was 79.61%. The average survival time of the miR-429 high expression group(miR-429 relative expression level ≥ 1.36)was 39.07±1.59 months, with a 95%CI: of 35.95-42.19; miR-429 in the low expression group(miR-429 relative expression level < 1.36). The average survival time was 23.57±1.02 months, with a 95%CI of 21.57-25.58(P<0.05). The average survival time of the miR-200C high expression group(miR-200C relative expression ≥0.53)was(38.28±1.71)months the 95%CI was 34.94-41.63; and the miR was-200C in the low expression group(miR-200C relative expression <0.53 )The average survival time was 23.52±1.07 months, 95%CI: 21.42-25.62(P<0.05). Conclusion The relative expression levels of miR-429 and miR-200C in nasopharyngeal carcinoma patients at different pathological stages, T stages, N stages and clinical stages were different, and the expression levels of miR-429 and miR-200C decreased as the severity of the disease increased. The survival time of nasopharyngeal carcinoma patients decreased when the relative expression of miR-429 was <1.36 and the relative expression of miR-200C was <0.53.

Key words: Nasopharyngeal carcinoma, miR-429, miR-200C, Prognosis, Survival analysis