title: Unfavourable clinical implications for HLA-G expression in acute myeloid leukaemia.
abstract: Human leukocyte antigen-G (HLA-G) molecule exerts multiple immunoregulatory functions that have been suggested to contribute to the immune evasion of tumour cells. Studies on HLA-G expression in malignant haematopoietic diseases are controversial, and the functions of HLA-G on this context are limited. In the current study, HLA-G expression was analysed in different types of patients: de novo acute myeloid leukaemia (AML, n = 54), B cell acute lymphoblastic leukaemia (B-ALL, n= 13), chronic myeloid leukaemia (CML, n= 9) and myelodysplastic syndrome (MDS, n= 11). HLA-G expression was observed in 18.5% cases of AML, 22.2% in CML and 18.2% in MDS, but not in B-ALL patients. In AML, HLA-G-positive patients had a significant higher bone marrow leukaemic blast cell percentage when compared with that of HLA-G-negative patients (P < 0.01). Total T-cell percentage was dramatically decreased in HLA-G-positive patients (P < 0.05). Cytogenetic karyotyping results showed that all HLA-G-positive AML patients (n= 5) were cytogenetically abnormal, which was markedly different from that of HLA-G-negative patients (P < 0.01). Ex vivo cytotoxicity analysis revealed that HLA-G expression in AML leukaemic cells could directly inhibit NK cell cytolysis (P < 0.01). These findings indicated that HLA-G expression in AML is of unfavourable clinical implications, and that HLA-G could be a potential target for therapy.
authors.affiliation: Medical Research Center, Taizhou Hospital of Zhejiang province, Wenzhou Medical College, Linhai, Zhejiang, People's Republic of China. yanwhcom@yahoo.com
authors.forename: W-H
authors.initials: WH
authors.lastname: Yan
authors.forename: A
authors.initials: A
authors.lastname: Lin
authors.forename: B-G
authors.initials: BG
authors.lastname: Chen
authors.forename: W-D
authors.initials: WD
authors.lastname: Luo
authors.forename: M-Z
authors.initials: MZ
authors.lastname: Dai
authors.forename: X-J
authors.initials: XJ
authors.lastname: Chen
authors.forename: H-H
authors.initials: HH
authors.lastname: Xu
authors.forename: B-L
authors.initials: BL
authors.lastname: Li
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology; D002871:Chromosome Banding; D003601:Cytotoxicity Tests, Immunologic; D005260:Female; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D006680:HLA Antigens / Q000276:immunology* / Q000378:metabolism; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D016130:Immunophenotyping; D007621:Karyotyping; D007694:Killer Cells, Natural / Q000276:immunology; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D015470:Leukemia, Myeloid, Acute / Q000145:classification / Q000175:diagnosis* / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D013601:T-Lymphocytes / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D005456:Fluorescent Dyes; D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I; D007770:L-Lactate Dehydrogenase; D016650:Fluorescein-5-isothiocyanate