title: Creatine kinase BB isoenzyme levels in tumour cytosols and survival of breast cancer patients.
abstract: Creatinine kinase BB (CK-BB) is elevated in many tumours including those of the breast. We have recently described a new, highly sensitive and specific method for measuring CK-BB, based on monoclonal antibodies and time-resolved fluorometry. Using this method, we quantitated CK-BB in 172 breast tumour cytosols and examined the associations between CK-BB and other clinicopathological variables and patient survival. High CK-BB levels were seen more frequently in tumours from patients who were younger (age < 50 years), patients who qualified for chemotherapy and patients with oestrogen receptor-positive tumours. No association was seen between CK-BB and tumour stage, grade, size, histological type or the progesterone receptor. In univariate analysis, the risk of relapse or death was higher in the group with tumours containing high CK-BB levels but the difference did not reach statistical significance. In multivariate analysis, the risk of death was statistically significantly higher in the high-CK-BB group. Analysis of subsets of patients revealed that patients with oestrogen receptor-negative cancer have higher risk of death if their tumours contain high levels of CK-BB. Our data suggest that, in general, CK-BB is associated with more aggressive tumours but its value as a prognostic indicator is limited. CK-BB content of breast tumours may be more useful as an aid in selecting therapy directed at inhibiting this enzyme activity and thus depriving tumour cells of their energy source.
authors.affiliation: Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Zarghami
authors.forename: M
authors.initials: M
authors.lastname: Giai
authors.forename: H
authors.initials: H
authors.lastname: Yu
authors.forename: R
authors.initials: R
authors.lastname: Roagna
authors.forename: R
authors.initials: R
authors.lastname: Ponzone
authors.forename: D
authors.initials: D
authors.lastname: Katsaros
authors.forename: P
authors.initials: P
authors.lastname: Sismondi
authors.forename: E P
authors.initials: EP
authors.lastname: Diamandis
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000201:enzymology*; D003402:Creatine Kinase / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012044:Regression Analysis; D016019:Survival Analysis
chemical_list: D014408:Biomarkers, Tumor; D007527:Isoenzymes; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D003402:Creatine Kinase