A nuclear protein complex containing high mobility group proteins B1 and B2, heat shock cognate protein 70, ERp60, and glyceraldehyde-3-phosphate dehydrogenase is involved in the cytotoxic response to DNA modified by incorporation of anticancer nucleoside analogues.
Thiopurine treatment of human leukemia cells deficient in components of the mismatch repair system (Nalm6) initiated apoptosis after incorporation into DNA, as revealed by caspase activation and terminal deoxynucleotidyl transferase-mediated nick end labeling assay. To elucidate the cellular sensor(s) responsible for recognition of DNA damage in cells with an inactive mismatch repair system, we isolated a multiprotein nuclear complex that preferentially binds DNA with thioguanine incorporated. The components of this nuclear multiprotein complex, as identified by protein mass spectroscopy, included high mobility group proteins 1 and 2 (HMGB1, HMGB2), heat shock protein HSC70, protein disulfide isomerase ERp60, and glyceraldehyde 3-phosphate dehydrogenase. The same complex was also shown to bind synthetic oligodeoxyribonucleotide duplexes containing the nonnatural nucleosides 1-beta-D-arabinofuranosylcytosine or 5-fluoro-2'-deoxyuridine. Fibroblast cell line derived from Hmgb1(-/-) murine embryos had decreased sensitivity to thiopurines, with an IC(50) 10-fold greater than Hmgb1-proficient cells (P < 0.0001) and exhibited comparable sensitivity to vincristine, a cytotoxic drug that is not incorporated into DNA. These findings indicate that the HMGB1-HMGB2-HSC70-ERp60-glyceraldehyde 3-phosphate dehydrogenase complex detects changes in DNA structure caused by incorporation of nonnatural nucleosides and is a determinant of cell sensitivity to such DNA modifying chemotherapy.
Krynetski
Eugene Y
EY
Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
Krynetskaia
Natalia F
NF
Bianchi
Marco E
ME
Evans
William E
WE
D000964:Antimetabolites, Antineoplastic / Q000633:toxicity*; D001483:Base Sequence; D037282:Calreticulin / Q000187:drug effects / Q000378:metabolism*; D002453:Cell Cycle / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000187:drug effects / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000187:drug effects / Q000378:metabolism*; D006609:High Mobility Group Proteins / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D015448:Leukemia, B-Cell; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D009687:Nuclear Proteins / Q000187:drug effects / Q000378:metabolism*; D016196:S Phase / Q000187:drug effects; D014407:Tumor Cells, Cultured
D000964:Antimetabolites, Antineoplastic; D037282:Calreticulin; D018840:HSP70 Heat-Shock Proteins; D006609:High Mobility Group Proteins; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases