title: Relationship between p53 dysfunction, CD38 expression, and IgV(H) mutation in chronic lymphocytic leukemia.
abstract: Established adverse prognostic factors in chronic lymphocytic leukemia (CLL) include CD38 expression, relative lack of IgV(H) mutation, and defects of the TP53 gene. However, disruption of the p53 pathway can occur through mechanisms other than TP53 mutation, and we have recently developed a simple screening test that detects p53 dysfunction due to mutation of the genes encoding either p53 or ATM, a kinase that regulates p53. The present study was conducted to examine the predictive value of this test and to establish the relationship between p53 dysfunction, CD38 expression, and IgV(H) mutation. CLL cells from 71 patients were examined for IgV(H) mutation, CD38 expression, and p53 dysfunction (detected as an impaired p53/p21 response to ionizing radiation). Survival data obtained from 69 patients were analyzed according to each of these parameters. Relative lack of IgV(H) mutation (less than 5%; n = 45), CD38 positivity (antigen expressed on more than 20% of malignant cells; n = 19), and p53 dysfunction (n = 19) were independently confirmed as adverse prognostic factors. Intriguingly, all p53-dysfunctional patients and all but one of the CD38(+) patients had less [corrected] than 5% IgV(H) mutation. Moreover, patients with p53 dysfunction and/or CD38 positivity (n = 31) accounted for the short survival of the less mutated group. These findings indicate that the poor outcome associated with having less than 5% IgV(H) mutation may be due to the overrepresentation of high-risk patients with p53 dysfunction and/or CD38 positivity within this group, and that CD38(-) patients with functionally intact p53 may have a prolonged survival regardless of the extent of IgV(H) mutation.
authors.affiliation: Department of Haematology, Royal Liverpool University Hospital, United Kingdom.
authors.forename: Ke
authors.initials: K
authors.lastname: Lin
authors.forename: Paul D
authors.initials: PD
authors.lastname: Sherrington
authors.forename: Michael
authors.initials: M
authors.lastname: Dennis
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Matrai
authors.forename: John C
authors.initials: JC
authors.lastname: Cawley
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Pettitt
mesh_terms: D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000032:analysis*; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000276:immunology / Q000401:mortality; D008562:Membrane Glycoproteins; D009154:Mutation; D009244:NAD+ Nucleosidase / Q000032:analysis*; D011379:Prognosis; D015996:Survival Rate; D016159:Tumor Suppressor Protein p53 / Q000502:physiology*
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D008562:Membrane Glycoproteins; D016159:Tumor Suppressor Protein p53; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D009244:NAD+ Nucleosidase; D051997:ADP-ribosyl Cyclase 1