Expressions and clinical significance of DNA methyltransferase 1 in pancreatic carcinoma / 中华胰腺病杂志

ABSTRACT

Objective To investigate the expressions of DNA methyltransferase 1 (DNMT1) in pancreatic carcinoma and its clinical significance.Methods 30 samples of pancreatic cancer tissues and paired para-cancerous tissues were collected from patients who underwent curative pancreatectomy.The levels of DNMT1 mRNA were detected by real-time RT-PCR.Expressions of DNMT1 protein were detected by streptavidin peroxidase immunohistochemistry.The relationships between expression of DNMT1 and clinicopathological findings were analyzed.Results The value of relative quantification (RQ) of DNMT1 mRNA in human pancreatic cancer tissues was 2.32 (1.17 ～ 5.17 ), which was significant higher than 0.78 (0.07 ～3.14) in para-cancerous tissues(P ＜0.05).The index of expression of DNMT1 protein in human pancreatic cancer tissues was (54.5 ±21.2)% ,which was significant higher than( 10.9 ± 15.0)% in paracancerous tissues (P ＜ 0.01 ).Patients were divided into the high DNMT1 group (n = 19) with above 54.5% of the DNMT1 positively cancer cells and the low DNMT1 group ( n = 11 ) with less than 54.5% of the DNMT1 positively cancer cells.The high expression of DNMT1 was correlated significantly with clinical staging ( x2 =6.897, P = 0.029), lymph node metastasis ( x2 = 4.739, P = 0.029) and neural invasion ( x2 = 5.44, P =0.020).On the other hand, no association between DNMT1 expression and age, gender, tumor location,tumor size, tumor differentiation, the serum CEA and CA19-9 levels could be found.Conclusions DNMT1 mRNA and protein was highly expressed in pancreatic cancer tissues.High expression of DNMT1 might be related to the aggressiveness of pancreatic cancer, lymph node metastasis and neural invasion.