BACKGROUND Molecules that are highly expressed by human prostate cancers may serve as therapeutically relevant targets or tumor markers. Tyrosine kinases are frequently overexpressed in metastatic tumor cells and this prompted us to screen for tyrosine kinases that are overexpressed in prostate cancer cells. METHODS Expression levels of the EphA2 receptor tyrosine kinase were determined by Western blot analysis in canine and human prostate cancer cell lines and in immortalized and transformed variants of 267B1 prostatic epithelial cells. EphA2 levels in benign human prostate and prostate cancers were also determined in formalin‐fixed, paraffin‐embedded tissues using immunohistochemical staining. RESULTS Metastatic prostate cancer cells overexpressed EphA2 by 10‐100 fold as compared with non‐invasive prostatic epithelial cells. EphA2 immunoreactivity in vivo was also significantly greater in human prostate cancers as compared with benign prostate epithelium. CONCLUSIONS The EphA2 receptor tyrosine kinase is differentially expressed in human and canine prostate cancer cell lines and overexpressed in human prostate cancers as compared with benign prostate tissues. Metastasis‐derived canine prostate carcinoma cell lines overexpress EphA2 and may provide pre‐clinical models to further evaluate the role of EphA2 in prostate carcinogenesis. Further investigations are needed to determine the utility of EphA2 as a tumor marker and a novel target in human prostate cancer. Prostate 41:275–280, 1999. © 1999 Wiley‐Liss, Inc.

Further studies are needed to determine if PTP1B overexpression balances or augments PTK activity. PTP1B overexpression might also be evaluated as a clinical prognostic factor in human breast cancers.

Background. Several molecular‐genetic alterations in endometrial cancers, including aneuploidy and aberrant expression of p53 and HER‐2/neu, have been associated with poor prognosis. To determine the importance of molecular‐genetic factors relative to more traditional surgical‐pathologic prognostic factors, a multivariable analysis was performed. Methods. Immunohistochemical staining for p53, HER‐2/neu, estrogen receptor, progesterone receptor, and epidermal growth factor receptor was performed on frozen sections from 100 primary endometrial cancers. DNA ploidy was determined using computerized image analysis of Feulgen‐stained touch preparations. In addition, information regarding surgical‐pathologic features of the cancers was obtained. Univariable analysis was performed followed by multivariable analysis using Cox's proportional hazards model to identify variables predictive of poor prognosis. Results. With univariable analysis, race, histologic type, stage, grade, myometrial invasion, estrogen receptor, progesterone receptor, ploidy, p53 and HER‐2/neu were predictive of the presence of persistent or recurrent disease. In the multivariable analysis, only International Federation of Gynecology and Obstetrics stage (P = 0.005), grade (P = 0.005), myometrial invasion (P = 0.024), and ploidy (P = 0.028) were significant. Conclusions. Among molecular‐genetic prognostic factors, DNA ploidy was the most strongly predictive of persistent or recurrent disease.

Acne keloidalis is a chronic scarring folliculitis located on the posterior neck of young black men. It is manifest clinically by follicular papules that coalesce into firm plaques and nodules. Examination of early lesions shows that inflammation begins at the deep infundibular and isthmic levels of the hair follicle and is accompanied by absence of sebaceous glands. The etiology of acne keloidalis is uncertain, but centers around anatomic, infectious, and autoimmune theories. Successful surgical therapy of advanced cases can be carried out using a number of methods as long as subfollicular destruction of the process is achieved.