Objective To evaluate the feasibility of testing the high methylation of ppENK gene in stool with methylation-specific polymerase chain reaction (MSP) assay in pancreatic cancer diagnosis.Methods Twenty-four fresh stool samples of pancreatic cancer patients and six healthy control samples were collected.The methylation status of ppENK gene in all the stool samples was detected by MSP assay.The positive rate of wild-type ppENK gene in all the stool samples was determined by polymerase chain reaction (PCR).And 10 non wild-type ppENK gene negative pancreatic cancer samples were collected,and K-ras gene mutation was detected by PCR-restriction fragment length polymorphism (RFLP).The single cell suspension of pancreatic cancer PC3 cell line was added into stool sample from the same healthy individual,the positive rate of ppENK gene methylation was detected by MSP assay.The minimum number of pancreatic cancer cell was calculated when methylation was positive.Results The rate of methylation detection in 30 samples was 0 (0/30); and the rate of non-methylation detection was 10％ (3/30).The rate of wild-type ppENK detection was 6.7％ (2/30).By PCR-RFLP assay,eight were successfully amplified and seven had mutation in 12th code of K-ras gene in 10 selected wild-type ppENK gene negative pancreatic cancer samples.The minimum number of pancreatic cancer cells needed for ppENK methylation band positive detected by MSP was 50 cell/ml.Conclusion Detecting ppENK gene methylation status in stool samples of pancreatic cancer patients by MSP assay has not yet become the method of pancreatic cancer screening and diagnosis.

Objective To investigate the suppression effects of tumor suppressor gene p53 alone and apoptosis incombination with TNF-? in a hepatocellular carcinoma cell line Hep3B. Methods Hep3B cells were transfected with a wild-type p53 cDNA(wt-p53)and plain vector(pNeo) respectively. Then the cell were cultured for 12 hours, one of the transfected p53 groups was added TNF-?(20 ?g/ml). The expression of p53 was detected by immunological fluorescence assay. Determination of apoptosis was used by DNA fragmentation, TUNEL assay. Results Both a small dose TNF-? and wt-p53 can induce apoptosis more efficiently comparing with non-transfected cultures(P

Colonoscopy has been accepted as the standard method for evaluation of colon and rectum,its success rate depends on the quality of bowel preparation. Aims:To evaluate the cleanliness and tolerance of fractionated dose versus single dose polyethylene glycol electrolyte solution( PEG-ES) bowel preparation regimens for colonoscopy. Methods:A total of 427 consecutive asymptomatic individuals undergoing colorectal cancer screening were enrolled and randomly assigned into 2 groups. Subjects in group A drank 1. 5 L PEG-ES on the eve and 4 hours before colonoscopy, respectively;subjects in group B received a single dose of 3 L PEG-ES 5 hours before colonoscopy. Score and degree of Boston bowel preparation scale(BBPS)and PEG-ES related adverse effects of the two groups were assessed and compared. Results:There were no significant differences in gender,age and cecal insertion rate between group A and group B(P ﹥ 0. 05). Score of BBPS was significantly higher in group A than in group B(P ﹤0. 01). Both regimens met the requirement of conventional colonoscopy,however,the cleanliness of colon was graded as excellent in more subjects of group A( P ﹤ 0. 01),and less subjects of group A complained PEG-ES related nausea(P ﹤0. 05). Logistic regression analysis revealed that the PEG-ES drinking pattern was associated with cleanliness of colon and occurrence of nausea( P ﹤ 0. 05). Conclusions:Fractionated dose PEG-ES regimen provides a better colonic cleansing quality and tolerance for bowel preparation of colonoscopy,which is superior to that of single dose regimen.