Relationship between inactivation of p16 gene and gastric carcinoma.
OBJECTIVE
To investigate the relationship between inactivation of p16 gene and gastric carcinoma, and the mechanism of inactivation of p16 gene in gastric carcinogenesis.


METHODS
40 fresh tumor tissue specimens were taken from primary gastric cancer patients. Expression of P16 protein was detected by immunohistochemical method. Deletion and point mutation of p16 gene were analyzed by polymerase chain reaction (PCR) and DNA sequencing, respectively.


RESULTS
The frequency of loss of P16 protein expression in the gastric cancer tissue, adjacent nontumor tissue, and distal normal tissue was 77.5 % (31/40), 55.0 % (22/40), and 17.5 % (7/40), respectively (P<0.005). Homozygous deletion of exon 1 and exon 3 was observed in two and three cases, respectively, giving an overall frequency of homozygous deletion of 12.5 %. All five cases had diffuse type gastric carcinoma. No p16 gene point mutation was detected.


CONCLUSIONS
These findings suggest a close correlation between inactivation of p16 gene and gastric carcinoma. Further investigations are needed to testify the mechanism of inactivation of p16 gene in gastric carcinogenesis.
Zhao
Guo-Hai
GH
Department of Surgery, the Affiliated Yijishan Hospital, Wannan Medical College, Wuhu 241001, Anhui Province, China. zhaoguohai@163.net
Li
Tie-Chen
TC
Shi
Liang-Hui
LH
Xia
Ya-Bin
YB
Lu
Lin-Ming
LM
Huang
Wen-Bin
WB
Sun
Hui-Lan
HL
Zhang
Yi-Sheng
YS
D000328:Adult; D000368:Aged; D001483:Base Sequence; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000378:metabolism; D004273:DNA, Neoplasm / Q000235:genetics; D005091:Exons; D005260:Female; D015870:Gene Expression; D019942:Genes, p16; D006720:Homozygote; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D017384:Sequence Deletion; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
D019941:Cyclin-Dependent Kinase Inhibitor p16; D004273:DNA, Neoplasm