Immunocytochemical staining of renal cancer cells for CA II, IV, IX, and XII. Caki-1, Caki-2, and A-498 cells show strong positive staining for CA II, whereas the signal in ACHN cells is less intense. None of the cell lines express CA IV. Only A-498 cells show positive immunostaining for CA IX, whereas Caki-2, ACHN, and A-498 are all positive for CA XII.