The Research Of DNA Methylation Markers,CD1D,for The Early Diagnosis Of Pancreatic Cancer

Purpose Incidence and mortality rates of pancreatic cancer continue to rise,and the degree of malignancy is high and the diagnosis is difficult.It is later found.It is of great clinical significance to find discriminant markers for pancreatic cancer early diagnosis.We sought to identify and validate methylated DNA markers,CD1 D,for pancreatic cancer using next-generation sequencing unbiased by known targets.We will obtain the expression of CD1 D in pancreatic cancer,the sensitivity and specificity of pancreatic cancer diagnosis.To evaluate the correlation between the CD1 D of methylated DNA markers and the gender,age,smoking,clinical stage of tumor,tumor site and other indicators in patients with pancreatic cancer.Methods This study was conducted through four consecutive case-control studies.In the first three studies based on organization,pancreatic cancer organization is the experimental group.There are two comparison groups,the first control group is normal pancreatic tissue,the second group is a colon epithelial tissue of patients with pancreatic cancer or colon tumors,20 cases respectively.First,the DNA of 20 pancreatic cancer tissues,20 normal pancreatic tissues and 20 normal colonic epithelial tissues was sequenced by RBBS,the methylated DNA markers are identified using residual variance logistic regression equations.Using a more sensitive test system(methylation-specific PCR)to validate these findings from a technical perspective,the findings were validated biologically from a separate,controlled tissue sample.The fourth study,using pancreatic juice as a study sample from clinical perspective,methylation candidates and mutant KRAS was performed on secretin-stimulated pancreatic juice samples from 20 patients with pancreatic cancer,20 with chronic pancreatitis,and 20 with normal pancreas on endoscopic ultrasound,ERCP or EST.Areas under receiver-operating char-acteristics curves(AUC)for markers were calculated,and the sensitivity and specificity of the two diagnoses were compared.Compare pancreatic and chronic pancreatitis with a 95%confidence interval(CI)and pancreatic cancer and normal pancreatic group.Logistic regression analysis was carried out on gender,age,smoking and clinical stages and sites of tumor.Using chi-square test to estimate the discrete parameters,it was concluded whether there was a correlation,and P<0.05 was considered to be statistically significant.Results By sequencing RRBS and MSP primer design test analysis measured group has38 of suspicious markers in pancreatic cancer tissue,the AUC value(95% confidence interval)of CD1 D,KCNK12,WT1 and CLEC11 A are respectively 0.95(0.92 1),0.92(0.93 1),0.90(0.86 1)and 0.86(0.84 1).The methylation value of the markers in the experimental group was 30 or more times higher than that in the control group.In the pancreatic test,the AUC value of the methylated DNA markers measured by RBBS sequencing method was between 0.72 and 0.94.The AUC value of CD1 D,KCNK12,CLEC11 A and KRAS in pancreatic cancer group and normal pancreatic pancreatic juice are 0.90(0.86-0.98),0.87(0.80-0.95),0.84(0.76-0.95)and 0.76(0.64-0.86)(P = 0.001).The AUC value of CD1 D,KCNK12,CLEC11 A and KRAS in pancreatic cancer and chronic pancreatitis group are 0.90(0.85-0.98),0.72(0.61-0.86),0.75(0.64-0.87)and0.64(0.49-0.74)(P = 0.03).The methylated DNA marker CD1 D could specifically identify the experimental group and the control group.CD1 D showed that 75% of patients with pancreatic cancer had a specificity of 94% and a false positive rate of 10%(P < 0.01).DNA methylation markers CD1 D with pancreatic cancer patients' gender,age,smoking,clinical stage,tumor site,tumor markers of correlation analysis of measured P values are 0.06,0.4,0.07,0.052,0.08,P>0.05,there is no statistically significant difference.Conclusions We identified and validated DNA methy-lation markers,CD1 D,strongly associated with pancreatic cancer.Age,sex,or current smoking did not significantly influence the strength of association between methylated marker,CD1 D,levels and pancreatic cancer.There were no significant differences when patients were stratified for T-stage 1 and 2 compared with T3 and 4 or for tumor location in the head of the pancreas compared with body and tail.