title: Single-strand breaks or alkali-sensitive sites in the DNA of human myeloma plasma cells and chronic lymphocytic leukemia lymphocytes.
abstract: Alkaline-elution studies showed significant levels of either DNA single-strand breaks or alkali-sensitive sites in the plasma cells of six out of six myeloma patients and in the lymphocytes of two out of four patients with chronic lymphocytic leukemia as compared with normal human lymphocytes. The increased rate of DNA elution was variable from sample to sample with a range that would correspond to that observed with 100-1000 rad (1 rad = 10 mGy) of X-ray irradiation. This alteration in DNA structure was observed in both new and advanced patients, did not appear to be related to prior therapy, and did not affect the in vitro viability of these cells. Repetitive alkaline-elution profiles obtained with tumor cells from three patients were similar on subsequent samples obtained 1 month apart. Altered DNA elution was not evident in peripheral blood lymphocytes from myeloma patients with altered plasma cell DNA elution. These observations are interesting in light of the recent hypothesis that breaking and rejoining of DNA, regulated by poly(ADP-ribosyl)ation, may be a general mechanism of altering gene expression during differentiation.
mesh_terms: D000468:Alkalies; D001402:B-Lymphocytes / Q000378:metabolism* / Q000473:pathology; D001853:Bone Marrow / Q000473:pathology; D002471:Cell Transformation, Neoplastic / Q000378:metabolism / Q000473:pathology; D004273:DNA, Neoplasm / Q000302:isolation & purification / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism*; D005260:Female; D006801:Humans; D007945:Leukemia, Lymphoid / Q000378:metabolism* / Q000473:pathology; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D009101:Multiple Myeloma / Q000378:metabolism* / Q000473:pathology; D010950:Plasma Cells / Q000378:metabolism* / Q000473:pathology
chemical_list: D000468:Alkalies; D004273:DNA, Neoplasm; D004277:DNA, Single-Stranded