Protein Expression of BLM Gene and Its Apoptosis Sensitivity in Hematopoietic Tumor Cell Strains / 华中科技大学学报（医学）（英德文版）

ABSTRACT

Patients with Bloom syndrome (BS) show an immunodeficiency, an enhanced sister chromatid exchanges (SCEs), a strong genetic instability and an increased predisposition to all. In order to investigate the differential expression of BLM protein in hematopoietic tumor cell strains and study the effects of BLM gene on ultraviolet (UV)- or hydroxyurea (HU)-induced apoptosis, Western blot was used to detect the expression of BLM protein in normal human bone marrow mononuclear cells and 4 kinds of hematopoietic tumor cell strains. The 4 kinds of hematopoietic tumor cells were exposed to UV light with a germicidal UV lamp or treated with 2 mmol/L hydroxyurea and the apoptotic rate was detected by using AnnexinV-FITC. The results showed that these tumor cells ex- pressed BLM protein higher than the normal human bone marrow mononuclear cells (P＜0.01). In the 4 hematopoietic tumor cells, BLM protein was all specially cleaved in response to UV- or HU-induced apoptosis. The increase of BLM protein expression may play an important role in the evelopment of these tumors, and BLM proteolysis is likely to be a general feature of the apoptotic esponse.