title: PCNA Ki-67 dissociation in childhood acute lymphoblastic leukaemia. An immunofluorescent laser confocal scanning microscopical study.
abstract: Cell proliferation rates of diagnostic marrow aspirate cells of 21 children with Acute Lymphoblastic Leukaemia and 16 controls were compared using immunocytochemical labelling of PCNA and Ki-67 antigen as assessed by Confocal Laser Scanning Microscopy. The results showed an unexpected, highly significant degree of dissociation between PCNA and Ki-67 expression in ALL blasts. The PCNA labelling indices of ALL patients were significantly increased (mean 44, range 24-77) compared with normal reactive marrow cells (mean 13.8, range 4-26) (p < 0.000001, Mann Whitney U two tailed test), suggesting an abnormal commitment to proliferation. Ki-67 expression was raised to a lesser extent in ALL cells (mean 14.8, range 1.2-35) when compared to non-malignant proliferations (mean 6.6, range 1.7-25) (p < 0.02). PCNA/Ki-67 LI ratios in ALL (mean 7, range 1.1-35) were higher than in controls (mean 2.7, range 1.04-6.5, p < 0.09). As cell proliferation rates actually achieved in the bone marrow do not differ as strongly as suggested by the extreme difference in PCNA labelling, a pathological dissociation of PCNA/Ki-67 expression exists, suggesting immortalisation.
authors.affiliation: Dep. of Paediatric Clinical Haematology, RLCH Alder Hey, United Kingdom.
authors.forename: L M
authors.initials: LM
authors.lastname: Ball
authors.forename: J
authors.initials: J
authors.lastname: Pope
authors.forename: C V
authors.initials: CV
authors.lastname: Howard
authors.forename: P
authors.initials: P
authors.lastname: Eccles
authors.forename: D
authors.initials: D
authors.lastname: van Velzen
mesh_terms: D000293:Adolescent; D000911:Antibodies, Monoclonal; D001853:Bone Marrow / Q000737:chemistry*; D002453:Cell Cycle; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D019394:Ki-67 Antigen; D008297:Male; D018613:Microscopy, Confocal; D009363:Neoplasm Proteins / Q000032:analysis*; D009687:Nuclear Proteins / Q000032:analysis*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000378:metabolism* / Q000473:pathology; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis*
chemical_list: D000911:Antibodies, Monoclonal; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen