BACKGROUNDTo investigate the different expressions of p53 gene family members p53, p63 and p73, and their clinical significance in non small cell lung cancer (NSCLC).

METHODSp53, p63 and p73 protein expressions were detected in 60 NSCLC tissues and 7 normal lung tissues by immunohistochemistry.

RESULTSIn NSCLC, positive rate of p53, p63 and p73 protein was 61.67%(37/60), 80.00%(48/60), 73.33% (44/60) respectively. There were significant differences in positive rate of three proteins as compared to normal lung tissue ( P < 0.05). p53 protein expression was closely associated with tumor cell differentiation degree ( P =0.023), but was not associated with histological classification, lymph node metastasis and clinical stages ( P > 0.05). Expression of p63 protein was closely related to lymph node metastasis ( P =0.028) and histological classification ( P =0.001), but not to cell differentiation degree and clinical stages ( P > 0.05). There was no significant relationship between p73 protein expression and clinical characteristics of NSCLC ( P > 0.05). A positive correlation was present between p63 and p73 protein expressions ( P =0.000 1). No statistical correlation was found between p53 and p73 ( P > 0.05).

CONCLUSIONSp53 gene family may be related to the oncogenesis and development of NSCLC. p63 and p73 proteins may have different biological function from p53 protein, and both might play oncogenic roles.