title: Enhanced down-regulation of ALCAM/CD166 in African-American Breast Cancer.
abstract: BACKGROUND
  Variation in tumor biology in African-American (AA) and Caucasian (CAU) women with breast cancer is poorly defined. Activated leukocyte cell adhesion molecule (ALCAM) is a bad prognostic factor of breast cancer yet it has never being studied in the AA population. We tested the hypothesis that ALCAM expression would be markedly lower in cases of AA breast cancer when compared to CAU.
  
  
  METHODS
  Cases of breast cancer among AA (n = 78) and CAU (n = 95) women were studied. Immunohistochemical staining was used to semi-quantitatively score ALCAM expression in tumor and adjacent non-tumor breast tissues. Clinico-pathological characteristics including histological type, histological grade, tumor size, lymph node metastasis, estrogen receptor (ER), progesterone receptor (PR), and HER2-neu status were abstracted, and their association with ALCAM expression tested.
  
  
  RESULTS
  Univariate analysis revealed that the level of ALCAM expression at intercellular junctions of primary tumors correlates with histological grade (AA; p = 0.04, CUA; p = 0.02), ER status (AA; p = 0.0004, CAU; p = 0.0015), PR status (AA; p = 0.002, CUA p = 0.034) and triple-negative tumor status (AA; p = 0.0002, CAU; p = 0.0006,) in both ethnic groups. Multivariate analysis demonstrated that ethnicity contribute significantly to ALCAM expression after accounting for basal-like subtype, age, histological grade, tumor size, and lymph node status. Compared to CAU tumors, the AA are 4 times more likely to have low ALCAM expression (p = 0.003).
  
  
  CONCLUSIONS
  Markedly low expression of ALCAM at sites of cell-cell contact in primary breast cancer tumors regardless of differentiation, size and lymph node involvement may contribute to the more aggressive phenotype of breast cancer among AA women.
authors.forename: Fang
authors.initials: F
authors.lastname: Tan
authors.forename: Marina
authors.initials: M
authors.lastname: Mosunjac
authors.forename: Amy L
authors.initials: AL
authors.lastname: Adams
authors.forename: Beverly
authors.initials: B
authors.lastname: Adade
authors.forename: Oleyad
authors.initials: O
authors.lastname: Taye
authors.forename: Yijuan
authors.initials: Y
authors.lastname: Hu
authors.forename: Monica
authors.initials: M
authors.lastname: Rizzo
authors.affiliation: Aflac Cancer Center and Blood Disorders Service, Department of Pediatrics, Emory University School of Medicine, 2015 Uppergate Drive, Atlanta, GA 30322, USA. sfo2@pitt.edu.
authors.forename: Solomon F
authors.initials: SF
authors.lastname: Ofori-Acquah
mesh_terms: D001741:Black or African American; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D001943:Breast Neoplasms / Q000208:ethnology / Q000378:metabolism* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000208:ethnology / Q000378:metabolism* / Q000556:secondary; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D005260:Female; D005326:Fetal Proteins / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D008207:Lymphatic Metastasis; D008875:Middle Aged; D010641:Phenotype; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D047368:Tumor Burden; D044465:White People; D020410:Activated-Leukocyte Cell Adhesion Molecule
chemical_list: D015703:Antigens, CD; D015816:Cell Adhesion Molecules, Neuronal; D005326:Fetal Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C105613:ALCAM protein, human; D020410:Activated-Leukocyte Cell Adhesion Molecule; C508053:ERBB2 protein, human