Comparison of expression patterns of keratin 6, 7, 16, 17, and 19 within multiple independent isolates of As super(+3)- and Cd super(+2)-induced bladder cancer. Keratin 6, 7, 16, 17, and 19 in bladder cancer

This laboratory has generated a series of seven cadmium (Cd super(+2))- and six arsenite (As super(+3))-transformed urothelial cancer cell lines by exposure of parental UROtsa cells to each agent under similar conditions of exposure. In this study, the seven Cd super(+2)-transformed cell lines were characterized for the expression of keratin 6, 16, and 17 while the six As super(+3) cell lines were assessed for the expression of keratin 7 and 19. The results showed that the series of Cd super(+2)-transformed cell lines and their respective transplants all had expression of keratin 6, 16, and 17 mRNA and protein. The expression of keratin 6, 16, and 17 was also correlated with areas of the urothelial tumor cells that had undergone squamous differentiation. The results also showed that four of the six As super(+3)-transformed cell lines had expression of keratin 7 and 19 mRNA and protein and produced subcutaneous tumors with intense focal staining for keratin 7 and 19. The other two As super(+3)-transformed cell lines had very low expression of keratin 7 mRNA and protein and produced subcutaneous tumors having no immunoreactivity for keratin 7; although keratin 19 expression was still present. The peritoneal tumors produced by one of these two cell lines regained expression of keratin 7 protein. The present results, coupled with previous studies, indicate that malignant transformation of UROtsa cells by Cd super(+2) or As super(+3) produce similar patterns of keratin 6, 7, 16, 17, and 19 in the resulting series of cell lines and their respective tumors.