Fourteen patients with various leukemias were examined and two with acute lymphoblastic leukemia and one with Waldenström's macroglobulinemia were identified to have mutations in the coding region of the p53 gene.
Acute lymphoblastic leukemia with low hypodiploid/near triploid karyotype is a specific clinical entity and exhibits a very high TP53 mutation frequency of 93%.
The p53 gene was examined in primary lymphoblasts of 25 pediatric patients with acute lymphoblastic leukemia by the RNase protection assay and by single strand conformation polymorphism analysis in 23 of 25 cases. p53 mutations were found to occur, but at a low frequency (4 of 25).
Marked overexpression was found in two cases of T-cell prolymphocytic leukemias and in four B-cell lineage acute lymphoblastic leukemia including one case with the t(8;14) and another case with a p53 mutation.
Frequency and clinical relevance of DNA microsatellite alterations of the CDKN2A/B, ATM and p53 gene loci: a comparison between pediatric precursor T-cell lymphoblastic lymphoma and T-cell lymphoblastic leukemia.
Amplification of the dihydrofolate reductase gene is a mechanism of acquired resistance to methotrexate in patients with acute lymphoblastic leukemia and is correlated with p53 gene mutations.
TP53 mutation does not confer a poor outcome in adult patients with acute lymphoblastic leukemia who are treated with frontline hyper-CVAD-based regimens.
Inactivated genes, such as <i>ASPP1, TP53, IKZF1</i> and <i>P15</i>, may correlate with poor prognosis in acute lymphoid leukemia (ALL), chronic lymphoid leukemia (CLL), chronic myelogenous leukemia (CML) and acute myeloid leukemia (AML), respectively.
In the present study, protein expressions of MDM2 and p53 were investigated by immunohistochemistry from bone marrow samples in 23 patients with acute lymphoblastic leukemia aged 1-13 years at diagnosis. p53 protein overexpression was detected in only one case, while overexpression of MDM2 was detected in samples from five patients.