摘要：The
P53 gene is a tumour suppressor, often inactivated by deletion and/or point
mutation in malignancies. The incidence of p53 mutation in haematological
malignancies varies with malignancy type and cell lineage affected. It is
associated with disease progression, poor prognosis and resistance to
chemotherapy. The wild-type p53 protein has a short half-life and cannot be
detected by immunocytochemistry, whereas the mutated form has an extended
half-life and can be.
Materials and methods .
Using lymphocyte cytospin preparations from patients with a range of
haematological malignancies, p53 mutation was assessed with immunocytochemistry.
Results .
83 patients showed intracellular p53 in 16 cases, including 4/18 (22%)
Non-Hodgkin’s lymphoma (NHL), 3/15 (20%) chronic lymphocytic leukaemia (CLL),
2/13 (15%) myeloma, 2/19 (11%) chronic myeloid leukaemia (CML), 1/3 (33%) hairy
cell leukaemia (HCL), 4/15 (27%) myelodysplatic syndromes (MDS) including two
transformed acute myeloid leukaemia (AML).
Using the Comet assay, lymphocytes from the p53 positive NHL, CLL, CML
and AML cases showed reduced damage to the alkylating agent, ethyl
methanesulfonate (EMS), when compared to p53 negative cases. Conclusions .
This suggested that mutant p53 positive cases are resistant to damage by
cytotoxic agents.
