TY - JOUR
T1 - Promoter hypermethylation of the p16 gene and loss of its protein expression is correlated with tumor progression in extrahepatic bile duct carcinomas
AU - Hong, Seung Mo
AU - Choi, Jene
AU - Ryu, Kyueun
AU - Ro, Jae
AU - Yu, Eunsil
PY - 2006/1/1
Y1 - 2006/1/1
N2 - Context.-The p16 gene is one of the tumor suppressor genes, and its inactivation results in abnormal regulation of the cell cycle in human neoplasms. Promoter hypermethylation, a mechanism of p16 gene inactivation, has been reported to play an important role in tumorigenesis and to be related to patient prognosis in several carcinomas. Objective.-To determine the role of the p16 gene in extrahepatic bile duct (EBD) carcinomas. Design.-We examined promoter hypermethylation of the p16 gene using a methylation-specific polymerase chain reaction and the expression of the p16 protein using an immunohistochemical staining method in 90 cases of EBD carcinomas. We then compared the data with various clinicopathologic parameters, including survival rate. Results.-Promoter hypermethylation was observed in 69 (77%) of the 90 cases. Of 69 hypermethylated cases, 32 (46%) demonstrated loss of p16 expression. Promoter hypermethylation of the p16 gene was more commonly observed in tumors with vascular invasion (22 [92%] of 24 cases) than without vascular invasion (71%, P = .03). Furthermore, p16 promoter hypermethylation with loss of p16 expression was more frequently observed in cases with lymph node metastasis (P = .006) and higher tumor stage group (P = .04). However, there was no significant difference in survival rate according to the status of p16 promoter methylation and/or p16 expression. Conclusion.-Promoter hypermethylation is an important mechanism in the inactivation of the p16 gene in EBD carcinogenesis. Furthermore, the loss of p16 expression, with or without p16 gene promoter hypermethylation, is closely related to the tumor progression in EBD carcinomas.
AB - Context.-The p16 gene is one of the tumor suppressor genes, and its inactivation results in abnormal regulation of the cell cycle in human neoplasms. Promoter hypermethylation, a mechanism of p16 gene inactivation, has been reported to play an important role in tumorigenesis and to be related to patient prognosis in several carcinomas. Objective.-To determine the role of the p16 gene in extrahepatic bile duct (EBD) carcinomas. Design.-We examined promoter hypermethylation of the p16 gene using a methylation-specific polymerase chain reaction and the expression of the p16 protein using an immunohistochemical staining method in 90 cases of EBD carcinomas. We then compared the data with various clinicopathologic parameters, including survival rate. Results.-Promoter hypermethylation was observed in 69 (77%) of the 90 cases. Of 69 hypermethylated cases, 32 (46%) demonstrated loss of p16 expression. Promoter hypermethylation of the p16 gene was more commonly observed in tumors with vascular invasion (22 [92%] of 24 cases) than without vascular invasion (71%, P = .03). Furthermore, p16 promoter hypermethylation with loss of p16 expression was more frequently observed in cases with lymph node metastasis (P = .006) and higher tumor stage group (P = .04). However, there was no significant difference in survival rate according to the status of p16 promoter methylation and/or p16 expression. Conclusion.-Promoter hypermethylation is an important mechanism in the inactivation of the p16 gene in EBD carcinogenesis. Furthermore, the loss of p16 expression, with or without p16 gene promoter hypermethylation, is closely related to the tumor progression in EBD carcinomas.
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M3 - Article
C2 - 16390235
AN - SCOPUS:30444450833
VL - 130
SP - 33
EP - 38
JO - Archives of Pathology and Laboratory Medicine
JF - Archives of Pathology and Laboratory Medicine
SN - 0003-9985
IS - 1
ER -