In vivo expression of p53 and Bcl-2 and their role in programmed cell death in premalignant and malignant lung lesions.
Forty-four specimens of non-malignant and malignant human lung tissue, taken from patients with non-small cell lung cancer (NSCLC), were examined for the expression of wild-type p53, mutant p53, and bcl-2 and the occurrence of programmed cell death (apoptosis). Wild-type p53 expression peaked in peritumoral and metaplastic samples, whereas mutant p53, bcl-2 and apoptosis were first detected in metaplasia and increased with progression to carcinoma. Bcl-2 positive samples had lower levels of apoptosis than bcl-2 negative samples and was independent of wild-type or mutant p53 expression. These results suggest that the over-expression of wild-type p53 may be an early cellular response to an alteration in normal cellular homeostasis. The ensuing increase in apoptosis appears to be relatively independent of mutant or wild-type p53 expression, but does not occur in cells expressing bcl-2.
Koty
Patrick P
PP
Department of Environmental and Occupational Health, University of Pittsburgh, 260 Kappa Drive, Pittsburgh, PA 15238, USA.
Zhang
Haifan
H
Franklin
Wilbur A
WA
Yousem
Samuel A
SA
Landreneau
Rodney
R
Levitt
Mark L
ML
D017209:Apoptosis; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000503:physiopathology*; D015972:Gene Expression Regulation, Neoplastic; D006706:Homeostasis; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000503:physiopathology*; D011230:Precancerous Conditions / Q000235:genetics* / Q000503:physiopathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53