Overexpression of Apg-2 increases cell proliferation and protects from oxidative damage in BaF3-BCR/ABL cells.
Apg-2, a mammalian heat-shock protein belonging to the heat-shock protein 110 (Hsp110) family, was previously found to be overexpressed in BaF3-BCR/ABL cells that were treated with hydrogen peroxide (H2O2) through our comparative proteomics study. The expression of Apg-2 in chronic myelogenous leukemia (CML) cells and its role have not been investigated, forming the basis for this study. BaF3-MIGR1 and BaF3-BCR/ABL cell lines stably overexpressing Apg-2 were established and exposed to 50 microM H2O2 for 10 min. Western blot analysis of Apg-2 expression confirmed that H2O2 treatment significantly up-regulated Apg-2 expression. Apg-2 overexpression elevated BaF3-BCR/ABL cell proportions in S and G2/M phase, increased cell proliferation and colony formation in vitro. Moreover, BaF3-MIGR1 and BaF3-BCR/ABL cells were exposed to 50 microM H2O2 in the absence or presence of Apg-2 overexpression and induction of H2AX phosphorylation, the reporters of DNA damage were assessed by Western blot and immunofluorescence. Results showed that exposure to H2O2 induced H2AX phosphorylation in BaF3-MIGR1 cells, but no increase was observed in BaF3-BCR/ABL cells. Together, the data indicate that Apg-2 is overexpressed and overexpression of Apg-2 in BaF3-BCR/ABL cells increases cell proliferation and protects cells from oxidative damage, which may play an important role in CML carcinogenesis and progression.
Li
Chunli
C
Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics Designated by the Ministry of Education, Chongqing Medical University, Chongqing 400016, P.R. China.
Liu
Dingbin
D
Yuan
Ying
Y
Huang
Shifeng
S
Shi
Meng
M
Tao
Kun
K
Feng
Wenli
W
D000818:Animals; D015153:Blotting, Western; D002453:Cell Cycle; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D003114:Colony-Forming Units Assay; D019610:Cytoprotection; D005455:Fluorescent Antibody Technique; D016044:Fusion Proteins, bcr-abl / Q000235:genetics / Q000378:metabolism*; D050957:HSP110 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology; D051379:Mice; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D010766:Phosphorylation; D054448:Precursor Cells, B-Lymphoid / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D013997:Time Factors; D014162:Transfection; D015854:Up-Regulation
D016044:Fusion Proteins, bcr-abl; D050957:HSP110 Heat-Shock Proteins; D006657:Histones; D006861:Hydrogen Peroxide; D016877:Oxidants; C485680:Hspa4 protein, mouse; C475961:gamma-H2AX protein, mouse