[Abnormality of p16 gene and its clinicopathological significance in non-small cell lung cancer].
OBJECTIVE
To investigate the ways of inactivation and expression of p16 gene mRNA and its protein as well, and their clinicopathological significance in non-small cell lung carcinomas (NSCLC).


METHODS
Comparative- multiplex PCR, in situ hybridization, and immunohistochemistry were used to detect the promotor methylation status, mRNA, and protein expression in 64 cases of NSCLC, respectively.


RESULTS
Promoter methylation of p16 gene was detected in 36 (56.3%) of 64 NSCLC cases. This positive result of methylation showed a negative correlation statistically with p16 protein expression by immunohistochemistry (P < 0.05). By in situ hybridization, 13 cases (20.3%) showed positive results for mRNA and all of these positive cases (13/13) had also a positive result by immunohistochemistry. Thirty-seven cases (57.8%) showed a negative immunohistochemical result. The metastatic rate of lymph nodes of those NSCLC patients with either promoter methylation or negative protein expression was higher (P = 0.038), and 3-year survival rate was lower statistically (P = 0.002).


CONCLUSIONS
Dysfunction of p16 gene in NSCLC is mainly caused by promoter methylation, and patients with p16 gene dysfunction may have a poor prognosis.
Fu
Jing
J
Department of Pathology, Beijing Haidian Hospital, Beijing 100080, China.
Zhang
Jun
J
Zhang
Hong-wei
HW
D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000473:pathology / Q000556:secondary; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000096:biosynthesis* / Q000235:genetics; D019175:DNA Methylation; D004273:DNA, Neoplasm / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D019942:Genes, p16; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008207:Lymphatic Metastasis; D011379:Prognosis; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D015996:Survival Rate
D019941:Cyclin-Dependent Kinase Inhibitor p16; D004273:DNA, Neoplasm; D012333:RNA, Messenger