title: Validation of flow-cytometric determination of Ki67 expression as a measure of growth factor response in acute myelogenous leukemia.
abstract: Despite its growing use as a marker of proliferation, the relationship between expression of the nuclear antigen Ki67 and other indices of proliferation in acute myelogenous leukemia (AML) has not been elucidated. In this study, short-term primary suspension cultures of human AML bone marrow cells were used to compare flow-cytometric methods of quantifying Ki67 expression and to test whether flow-cytometric determination of Ki67 expression correlates with incorporation of 3H-thymidine or bromodeoxyuridine (BrdU). BrdU incorporation was determined by staining of cells with anti-BrdU and propidium iodide (PI) followed by flow cytometry. When samples were double-labeled with Ki67 and PI, Ki67 was underestimated compared to single-color quantification of the nuclear antigen. Ki67+ cell number correlated well with incorporation of 3H-thymidine (r = 0.89, p < 0.001). Cells from 17 cases of AML were cultured for 3 days in the presence and absence of a variety of growth factors and growth factor combinations before comparison of Ki67 expression and BrdU incorporation. Ki67 expression correlated strongly with BrdU incorporation (r = 0.82, p < 0.001). Unlike the double-label with PI, containing with a phycoerythrin (PE)-labeled antibody directed against a cell surface antigen did not significantly affect Ki67 quantification. Flow cytometric determination of Ki67 is a simple and valid measurement of proliferation in AML bone marrow cells.
authors.affiliation: Johns Hopkins Oncology Center, Baltimore, MD 21287-8963.
authors.forename: S D
authors.initials: SD
authors.lastname: Gore
authors.forename: L J
authors.initials: LJ
authors.lastname: Weng
authors.forename: P J
authors.initials: PJ
authors.lastname: Burke
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001853:Bone Marrow / Q000473:pathology; D001973:Bromodeoxyuridine / Q000378:metabolism; D002452:Cell Count; D002455:Cell Division; D004273:DNA, Neoplasm / Q000096:biosynthesis; D005434:Flow Cytometry; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D007377:Interleukin-3 / Q000494:pharmacology; D019394:Ki-67 Antigen; D015470:Leukemia, Myeloid, Acute / Q000276:immunology / Q000473:pathology*; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis*; D009687:Nuclear Proteins / Q000032:analysis*; D016196:S Phase; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D006133:Growth Substances; D007377:Interleukin-3; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D016179:Granulocyte Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D001973:Bromodeoxyuridine