Figure 2.

Immunohistochemical findings in breast, ovarian, and cervical cancer and malignant melanoma, and corresponding benign tissue. (magnification 250×) a) Normal breast tissue with no detectable expression of the TRAP protein by immunohistochemistry. The brown staining in the duct is due to nonspecific staining of secretions. b) Invasive ductal carcinoma of the breast with significant expression of TRAP protein. (brown = DAB) c) Benign ovarian celomic epithelium with no expression of TRAP. d) Serous papillary ovarian cancer cells expressing TRAP (brown = DAB). e) No TRAP expression is detectable in non-transformed cervical tissue. f) Only weak expression of TRAP is seen in this cervical cancer specimen. Tumor-infiltrating monocytes clearly stain for TRAP, as shown in the enlarged section (brown = DAB). g) No expression of TRAP is detectable by immunohistochemistry in normal skin (VIP). The slight brown staining is due to skin pigmentation. h) There is marked overexpression of TRAP in the malignant melanoma in the same specimen as in (g), allowing differentiation of the malignant tumor from the adjacent normal skin. The slight brown staining is due to skin pigmentation. (purple = VIP)