Expression of prostate apoptosis response (Par-4) is associated with progesterone receptor in breast cancer.

BACKGROUND: The prostate apoptosis response (Par-4) gene encodes a proapoptotic protein that selectively induces apoptosis in cancer cells after diverse apoptotic stimuli. Par-4 expression and its association with other biomarkers have not been reported in breast cancer. The purpose of this study was to determine Par-4 expression in breast cancer samples and its association with other biomarkers and clinical factors (T-stage, age, nodal status). METHODS: Paraffin-embedded section samples of breast cancer were evaluated by immunohistochemical analysis to determine Par-4, estrogen receptor (ER), progesterone receptor (PgR), c-erbB2, Ki67, p53 and bcl-2 expression. The correlation between Par-4 and the other biomarkers and clinical factors was determined by multivariate analysis. RESULTS: Thirty five percent (n=21) of samples were PAR-4 positive and 64.4% (n=38) were negative. The hormonal status was 64% ER positive (n=38), 35% ER-negative (n=21) and 40.7% PgR positive (n=24), 59.3% PgR negative (n=35). The majority (90%) of the samples presented clear cytoplasmic localization and a small portion (10%) was cytoplasmic and nuclear. Univariate analysis indicates that the Par-4 expression has a significant inverse association (p=0.04) only with expression of PgR and not with the other variables analyzed. Normal breast tissue analyzed was negative for Par-4 immunostaining. CONCLUSIONS: Our results suggest that, in breast cancer, Par-4 plays a similar tumor suppressor gene role as reported in endometrial carcinoma.

Transitional cell carcinoma of the endometrium and endometrial carcinoma with transitional cell differentiation: a clinicopathologic study of 5 cases and review of the literature.

To date, only 16 cases of transitional cell carcinoma of the endometrium and endometrial carcinoma with transitional cell differentiation have been reported in the literature. We reviewed the clinicopathologic features of 5 cases of endometrial carcinoma with transitional cell differentiation. The mean age was 68 years, and all patients presented with postmenopausal bleeding. Macroscopically, the tumors were intracavitary and friable. Microscopically, the tumors were composed of tightly packed papillary structures with thin fibrovascular cores, resembling a transitional cell carcinoma of the urinary tract. One tumor showed exclusively transitional cell differentiation, whereas the remaining 4 neoplasms showed that the transitional cell carcinoma was admixed with a variable proportions of endometrioid adenocarcinoma. Four cases were in FIGO stage IB, whereas the remaining tumor infiltrated the uterine cervix (FIGO stage IIB). Immunoreactivity was typical of müllerian derivatives (cytokeratin 7 positive, cytokeratin 20 negative). p16 protein was positive in all cases, but human papillomavirus DNA was not detected in any of the tumors. None of the patients developed local recurrence or distant metastases, even though there are too few cases of transitional cell carcinoma of the endometrium reported to make any statistically valid conclusions about response to therapy and prognosis. Transitional cell carcinoma is an unusual variant of endometrial carcinoma, with distinctive histologic and immunophenotypic features. Identification of this variant broadens the morphological spectrum of epithelial neoplasms of the endometrium.