title: BCL2 expression in chronic lymphocytic leukemia: lack of association with the BCL2 938A>C promoter single nucleotide polymorphism.
abstract: High-level BCL2 expression is seen in most patients with chronic lymphocytic leukemia (CLL) in the absence of BCL2 chromosomal translocation. A single nucleotide polymorphism (SNP; -938C>A) within an inhibitory region of the BCL2 promoter has been reported to regulate BCL2 protein expression and to be associated with adverse prognostic features in CLL. We screened 276 patients with CLL for this SNP and 100 patients by quantitative Western blot for BCL2 expression. In contrast to the previous report, we found no association with BCL2 protein levels or with any clinical or laboratory parameters. BCL2 protein levels remained constant in 10 individual patients at different time points. A total of 19 patients with the lowest levels of BCL2 protein expression were biologically and clinically heterogeneous; 5 patients exhibited high-level BCL2 RNA expression and 4 were fludarabine resistant. BCL2 protein levels in CLL reflect a complex interplay of transcriptional and posttranscriptional controls, but do not appear to be associated with the -938C>A promoter SNP.
authors.affiliation: Medical Research Council Toxicology Unit, and Department of Haematology, University Hospitals, Leicester, UK.
authors.forename: Aneela
authors.initials: A
authors.lastname: Majid
authors.forename: Olga
authors.initials: O
authors.lastname: Tsoulakis
authors.forename: Renata
authors.initials: R
authors.lastname: Walewska
authors.forename: Stefan
authors.initials: S
authors.lastname: Gesk
authors.forename: Reiner
authors.initials: R
authors.lastname: Siebert
authors.forename: D Ben J
authors.initials: DB
authors.lastname: Kennedy
authors.forename: Martin J S
authors.initials: MJ
authors.lastname: Dyer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm / Q000187:drug effects / Q000235:genetics; D005260:Female; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects / Q000235:genetics; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012334:RNA, Neoplasm / Q000096:biosynthesis / Q000235:genetics; D050436:Regulatory Elements, Transcriptional / Q000235:genetics; D013997:Time Factors; D014178:Translocation, Genetic; D014740:Vidarabine / Q000008:administration & dosage / Q000031:analogs & derivatives
chemical_list: D000970:Antineoplastic Agents; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D014740:Vidarabine; C024352:fludarabine