Expression of anti-apoptotic protein survivin and tumor suppressor p53 protein in patients with pulmonary carcinoma

BACKGROUND: Survivin is one of the inhibitors of the apoptosis gene family that has been implicated in both inhibition of apoptosis and mitosis regulation. p53 is one of the tumor suppressor genes; prevents tumor formation through cell cycle blocking and eliminates damaged cells via activation of apoptosis. OBJECTIVE: To investigate the possible regulation of survivin by p53, we examined the expression of both proteins in 67 patients with diagnosed lung cancer using immunohistochemical visualization. RESULTS: Survivin was predominantly expressed in both nucleus and cytoplasm, whereas p53 was expressed in the nucleus. There was a negative correlation between survivin and p53 expression. A decreased intensity of expression and fewer cells positive for survivin in small cell lung cancer in comparison with other lung cancer types were detected. There was no significant difference in the intensity of expression and the number of cells positive for p53 between small cell and non-small cell lung cancer types. CONCLUSION: The present study suggests that survivin expression, as opposed to that of p53, is decreased in small cell lung cancer, which may differentiate this cancer from other lung cancer types other types.