Abstract
Objectives: Functional E-cadherin adhesion complexes are necessary to maintain the normal differentiated phenotype in bladder epithelial cells and dysfunction of molecules in this complex is associated with an invasive phenotype. Moreover, loss of functioning of E-cadherin and/or α-catenin in cancer cells is associated with a poor prognosis for bladder cancer patients. Clearly, other adhesion molecules are also involved in the process of invasion and/or metastasis. For example the expression of activated leukocyte cell adhesion molecule, ALCAM, an adhesion molecule belonging to the immunoglobulin superfamily, appeared to be correlated with malignant potential in human melanoma.
*Present address. Department of Urology, Faculty of Medicine, University of Tokyo, Japan.
Methods: The expression of ALCAM in human bladder cancer specimens was studied by immunohistochemistry and correlated with E-cadherin and α-catenin expression.
Results: In normal bladder tissue, only the umbrella cells showed positive membrane staining of ALCAM. In 19 out of 52 bladder cancer specimens, we found ALCAM staining, particularly in those areas that showed aberrant expression of α-catenin and E-cadherin.
Conclusions: There was a correlation between ALCAM expression in tumor cells and stage and grade, i.e. Ta-1:0/15, > T1: 19/37 (36.5%), G1: 0/5, G2: 2/14 (14.3%) and G3: 17/33 (51.5%) (Ta-1: > T1, G1:G2:G3, ). Moreover, positive ALCAM expression was strongly associated with a poor prognosis for bladder cancer patients. Multivariate analysis showed that ALCAM immunohistochemistry had additional prognostic value over pathological stage. Furthermore, it provides better prediction of prognosis when compared to grade and aberrant E-cadherin or α-catenin staining.
Notes
*Present address. Department of Urology, Faculty of Medicine, University of Tokyo, Japan.
†Present address. Department of Pathology, University of Colorado Health Sciences Center, Denver, CO, 80220, USA.