Abstract: Objective To investigate the expression and clinical significance of serum microRNA-451 (miR-451),miR-15a,miR-133b in patients with pancreatic cancer.Methods Between January 2021 and October 2024,195 patients with pancreatic cancer admitted to our hospital were regarded as the observation object,namely pancreatic cancer group,and 205 healthy volunteers who underwent physical examinations in our hospital during the same period were selected as the control group.The qRT-PCR method was performed to detect serum miR-451,miR-15a,and miR-13b.The general information of the subjects and the clinical features of the patients were recorded.Multivariate logistic regression was performed to analyze the factors affecting the occurrence of pancreatic cancer.ROC curve was used to analyze the diagnostic value of serum miR-451,miR-15a and miR-133b in pancreatic cancer.Results There was no prominent difference in BMI,drinking history,age,gender,and smoking history between control group and pancreatic cancer group (P>0.05).The levels of total cholesterol (TC) and triglycerides (TG) in the pancreatic cancer group were (1.92±0.28) mmol/L and (1.66±0.29) mmol/L respectively,which were higher than those in the control group [(1.85±0.22) mmol/L and (1.35±0.28) mmol/L].The difference was statistically significant (P<0.05).The levels of serum miR-451,miR-15a and miR-133b in the pancreatic cancer group were (0.84±0.12),(0.82±0.16),and (0.85±0.15),respectively,which were lower than those in the control group [(1.03±0.16),(1.01±0.19),and (1.02±0.16)].The difference was statistically significant (P<0.05).Elevated levels of serum miR-451,miR-15a and miR-133b are protective factors for pancreatic cancer (P<0.05);The AUCs of miR-451,miR-15a and miR-133b in the diagnosis of pancreatic cancer alone and in combination were 0.855,0.766,0.790,and 0.941,respectively.The combination of the three was superior to the individual diagnosis (Z=5.681、7.806、7.314，P＜0.001).There was no prominent difference in serum miR-451,miR-15a,and miR-133b among pancreatic cancer patients of different ages,tumor size,gender,and differentiation degree (P>0.05).In pancreatic cancer patients with lymph node metastasis,TNM stage Ⅲ-Ⅳ,and distant metastasis,the proportions of low expression of serum miR-451,miR-15a,and miR-133b were higher than the proportions of high expression (P<0.05).Conclusion Serum miR-451,miR-15a,miR-133b in patients with pancreatic cancer are decreased.The three factors have certain diagnostic value for pancreatic cancer,and are related to the clinical pathological features.

Key words: pancreatic cancer, microRNA-451, microRNA-15a, microRNA-133b, diagnostic value, clinical pathological features