ABSTRACT
Objective To establish the blood Septin9 methylation detection system for early screening of colorectal cancer based on fluorescence PCR technology .Methods The PCR primer of Septin9 was designed by searching the CpG island site of Septin9 methylation in the NCBI database .The high methylation site of Septin9 gene promoter region was confirmed by PCR amplification and sequencing after extracting DNA from colorectal cancer and para-carcinoma tissues .The fluorescence PCR and TaqMan probe detection technique was designed by aiming at high methylation site for constructing the plasma sample methylation detection sys-tem .Then its accuracy ,specificity ,repeatability and minimum detectable amount were performed the assess-ment and analysis .The SETP9 methylation detection was performed in plasma samples from 57 cases of color-ectal cancer and 30 healthy persons .Results The high methylation site of Septin9 gene in tissue samples was confirmed by sequencing .This site served as the target for designing fluorescence PCR detection system .After assessment ,the accuracy ,specificity and repeatability of this detection system were 100％ ,the lowest detection amount reached 0 .1 ng/μL .Among the plasma samples in 57 cases of colorectal cancer ,the positive rate of Septin9 methylation site detection was 71 .92％ (41/57) and the positive rate of in the patients with pathologi-cal stage Ⅰ and Ⅱ of colorectal cancer reached 64 .2％ .But Septin9 gene had no methylation in plasma of healthy population .Conclusion The plasma fluorescence PCR detection system with Septin9 gene methylation as the target has the characteristics of high sensitivity ,high specificity and high accuracy ,which is the reliable detection technique for the early screening of colorectal cancer and has good clinical application prospect .
ABSTRACT
Objective The aim of our study was to explore the relationship between prostate cancer and four serum markers,including Prostate specific antigen (PSA),Beta 2 Microglobulin (β2M),Neutrophil-to-lympochyte ratio (NLR) and Lactic dehydrogenase (LDH),and their variation rules in development of prostate cancer.Then to find one or more markers that can increase the sensitivity and specificity of diagnosis to provide reference for clinic.Methods A total of 149 prostate cancer patients,40 patients with benign prostatic hyperplasia,80 healthy subjects in our hospital were analyzed,and subsequent the T-PSA,F-PSA,β2M,LDH and NLR were measured.The correlation between these markers and prostate cancer as well as its different types and Gleason score was assessed statistically.We determined the cut-off point of the NLR and T-PSA according to the specificity and sensitivity levels derived from area under receiver operator characteristic (ROC) curve.Results The level of T-PSA was significantly higher in patients of prostate cancer and benign prostatic hyperplasia,and the level of NLR was higher only in patients of prostate cancer.Based on the area under ROC,the cut-off value of T-PSA was determined to be 4.625 ng/ml,and NLR was 2.11,and combined NLR and T-PSA can increase the specificity of diagnose.There is a statistical difference in Gleason scores in patients with different NLR of prostate cancer (P =0.030).Conclusions It could increased the specificity when combined NLR and T-PSA to diagnose prostate cancer.And NLR has positive correlation with the prognosis of patients of prostate cancer as well.
