Biologic role of activated leukocyte cell adhesion molecule overexpression in breast cancer cell lines and clinical tumor tissue.

TY - JOUR

T1 - Biologic role of activated leukocyte cell adhesion molecule overexpression in breast cancer cell lines and clinical tumor tissue.

AU - Hein, Sybill

AU - Müller, Volkmar

AU - Köhler, Nadine

AU - Wikman, Harriet

AU - Krenkel, Sylke

AU - Streichert, Thomas

AU - Schweizer, Michaela

AU - Riethdorf, Sabine

AU - Assmann, Volker

AU - Henningsen, Maike

AU - Beck, Katrin

AU - Issa, Rana

AU - Jänicke, Fritz

AU - Pantel, Klaus

AU - Milde-Langosch, Karin

PY - 2011

Y1 - 2011

N2 - 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.

AB - 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.

M3 - SCORING: Journal article

VL - 129

SP - 347

EP - 360

JO - BREAST CANCER RES TR

JF - BREAST CANCER RES TR

SN - 0167-6806

IS - 2

M1 - 2

ER -