Biologic role of activated leukocyte cell adhesion molecule overexpression in breast cancer cell lines and clinical tumor tissue.
The activated leukocyte cell adhesion molecule (ALCAM) is overexpressed in many mammary tumors, but controversial results about its role and prognostic impact in breast cancer have been reported. Therefore, we evaluated the biologic effects of ALCAM expression in two breast cancer cell lines and a larger cohort of mammary carcinomas. By stable transfections, MCF7 cells with ALCAM overexpression and MDA-MB231 cells with reduced ALCAM levels were generated and analyzed in functional assays and cDNA microarrays. In addition, an immunohistochemical study on 347 patients with breast cancer with long-term follow-up and analysis of disseminated tumor cells (DTCs) was performed. In both cell lines, high ALCAM expression was associated with reduced cell motility. In addition, ALCAM silencing in MDA-MB231 cells resulted in lower invasive potential, whereas high ALCAM expression was associated with increased apoptosis in both cell lines. Among genes which were differentially expressed in clones with altered ALCAM expression, there was an overlap of 15 genes between both cell lines, among them cathepsin D, keratin 7, gelsolin, and ets2 whose deregulation was validated by western blot analysis. In MDA-MB231 cells, we observed a correlation with VEGF expression which was validated by enzyme-linked immuno sorbent assay (ELISA). Our IHC results on primary breast carcinomas showed that ALCAM expression was associated with an estrogen receptor-positive phenotype. In addition, strong ALCAM immunostaining correlated with nodal involvement and the presence of tumor cells in bone marrow. By Kaplan-Meier analysis, strong ALCAM expression in ductal carcinomas correlated with shorter recurrence-free intervals (P=0.048) and overall survival (OAS, P=0.003). Our results indicate that the biologic role of ALCAM in breast cancer is complex, but overexpression might be relevant for outcome in ductal carcinomas.
Department of Gynecology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
Sibyll
S
Hein
Volkmar
V
Müller
Nadine
N
Köhler
Harriet
H
Wikman
Sylke
S
Krenkel
Thomas
T
Streichert
Michaela
M
Schweizer
Sabine
S
Riethdorf
Volker
V
Assmann
Maike
M
Ihnen
Katrin
K
Beck
Rana
R
Issa
Fritz
F
Jänicke
Klaus
K
Pantel
Karin
K
Milde-Langosch
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D017209:Apoptosis; D001943:Breast Neoplasms / Q000098:blood supply / Q000235:genetics / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000098:blood supply / Q000235:genetics / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D002448:Cell Adhesion; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D002465:Cell Movement; D016009:Chi-Square Distribution; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005326:Fetal Proteins / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D018919:Neovascularization, Physiologic; D020411:Oligonucleotide Array Sequence Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D015996:Survival Rate; D013997:Time Factors; D046888:Tissue Array Analysis / Q000379:methods; D014162:Transfection; D015854:Up-Regulation; D020410:Activated-Leukocyte Cell Adhesion Molecule
D015703:Antigens, CD; D015816:Cell Adhesion Molecules, Neuronal; D005326:Fetal Proteins; C105613:ALCAM protein, human; D020410:Activated-Leukocyte Cell Adhesion Molecule