Prognostic significance of p53 and Bcl-2 in acute lymphoblastic leukemia

P53 and Bcl-2 protein accumulation and mutations have been found in a wide variety of cancers including different types of leukemia, with varying frequencies. The objective of our study is to find out the correlation between p53 and Bcl-2 protein expression with respect to overall survival of patient taking clinical features and hematological parameters into consideration. Acute lymphoblastic leukemia (ALL) patients, 100 de novo and 10 relapse, were investigated taking different percentage of stained lymphocytes of patients into consideration. Immunocytochemistry and Western blot analysis were used to investigate protein expression. PCR-SSCP technique was used to detect point Mutations in exon 5, 6, 7 and 8 of p53 gene. P53 protein expression is of prognostic significance in univariate analysis and when combine with Bcl-2 expression data it provides additional information about overall survival. p53 and Bcl-2 failed to provide additional prognostic information in multivariate analysis. None of the samples shows mutation in exon 5, 6, 7 and 8 of p53 gene. Contrary to previous reports, p53 negativity was associated with lower relapse-free survival. Lower p53 expression was associated with improved disease-free survival. The correlation of p53 and Bcl-2 expression data with respect to clinical outcome may shed new sight into the biological significance of p53/Bcl-2 protein.