Brief communication HLA class I expression in bladder carcinomas

Correspondence to: Dr Federico Garrido Hospital Universitario Virgen de las Nieves Department de Análisis Clı́nicos Avd. Fuerzas Armadas n 2 18014 Granada Spain Tel: þ34 958 283147] Fax: þ34 958 283147 e-mail: federico.garrido. [email protected] Abstract: HLA class I molecules are frequently lost in a large variety of human carcinomas, possibly because of T-cell immune selection of major histocompatibility complex class I deficient tumor variants. We report that this phenomenon is also a frequent event in bladder carcinomas. Of a total of 72 bladder carcinomas, 72% of the tumors had at least one alteration in HLA class I expression. These altered HLA class I phenotypes were classified as total HLA class I loss (25%; phenotype I); HLA-A or/and HLA-B locus-specific loss (12%; phenotype III); and HLA class I allelic loss (35%; phenotype II or IV). Comparison of histopathological parameters with HLA class I expression showed a statistically significant relationship with the degree of differentiation and tumor recurrence.