p63 expression in adamantinoma.

Adamantinoma is a rare primary bone neoplasm with epithelial differentiation that is frequently associated with a concomitant fibrous component. Clinical, cytogenetic and histomorphologic overlap has previously been described with osteofibrous dysplasia, thereby suggesting a relationship between these two lesions. We performed a retrospective review of our archives to characterize the clinical and pathologic aspects of adamantinoma and osteofibrous dysplasia diagnosed at our institution, and to compare the expression patterns of p63 and keratin. Nine cases of adamantinoma (six classical, three osteofibrous dysplasia-like) and 11 cases of osteofibrous dysplasia were identified. The epithelial component in adamantinoma was found to stain for p63. Rare cells expressing p63 were also identified in eight cases of osteofibrous dysplasia. Expression of p63 was not identified in any of the five cases of fibrous dysplasia controls. The presence of staining for p63, albeit rare, in osteofibrous dysplasia supports the notion of a possible relationship between osteofibrous dysplasia and adamantinoma. Furthermore, our results suggest that, in some situations, p63 may be useful in helping differentiate metastatic carcinoma from adamantinoma.

Human kallikrein 11: a new biomarker of prostate and ovarian carcinoma.

Human kallikrein 11 (hK11) is a putative serine protease of the human kallikrein gene family. Currently, no methods are available for measuring hK11 in biological fluids and tissues. Our aim was to develop immunological reagents and assays for measuring hK11 and examine if the concentration of this kallikrein is altered in disease states. We produced recombinant hK11 protein in a baculovirus system and used it to develop monoclonal and polyclonal antibodies against hK11. We then developed an immunofluorometric procedure for measuring hK11 in biological fluids and tissue extracts with high sensitivity and specificity. We further quantified hK11 in various biological fluids and in serum of patients with various cancers. The hK11 immunofluorometric assay is highly sensitive (detection limit, 0.1 microg/l) and specific (no detectable cross-reactivity for other homologous kallikreins). We established the tissue expression pattern of hK11 at the protein level and found the highest levels in the prostate, followed by stomach, trachea, skin, and colon. We have immunohistochemically localized hK11 in epithelial cells of various organs. We further detected hK11 in amniotic fluid, milk of lactating women, cerebrospinal fluid, follicular fluid, and breast cancer cytosols. However, highest levels were seen in prostatic tissue extracts and seminal plasma. hK11 in seminal plasma and prostatic extracts is present at approximately 300-fold lower levels than prostate-specific antigen and at approximately the same levels as hK2. hK11 expression in breast cancer cell lines is up-regulated by estradiol. Elevated serum levels of hK11 were found in 70% of women with ovarian cancer and in 60% of men with prostate cancer. This is the first reported immunological assay for hK11. Analysis of this biomarker in serum may aid in the diagnosis and monitoring of ovarian and prostatic carcinoma.