Isaiah G. Schauer

Elevated epithelial expression of interleukin-8 correlates with myofibroblast reactive stroma in benign prostatic hyperplasia.

OBJECTIVES Numerous inflammatory diseases display elevated interleukin (IL)-8, and most are associated with a reactive stroma. IL-8 expression is also elevated in benign prostatic hyperplasia (BPH), yet little is known about reactive stroma in BPH. Whether a reactive stroma response exists in BPH, whether this correlates with elevated IL-8, and whether IL-8 can induce a reactive stroma phenotype have not been determined. This study was designed to specifically address these issues. METHODS Normal prostate transition zone tissue and BPH specimens, as identified by the Baylor College of Medicine pathology department, were examined by quantitative immunohistochemistry to correlate IL-8, smooth muscle alpha-actin, vimentin, calponin, and tenascin-C. In addition, human prostate stromal cell cultures were used to evaluate the effect of IL-8 on the expression of reactive stroma biomarkers. RESULTS BPH nodules exhibited elevated epithelial IL-8 immunoreactivity, and this correlated with elevated smooth muscle alpha-actin, reduced calponin, and altered deposition of tenascin-C, relative to the normal prostate transition zone tissue (P <0.05). Multiple vimentin-positive prostate stromal fibroblast cultures were induced by IL-8 to also co-express smooth muscle alpha-actin and tenascin-C, typical of a reactive stroma myofibroblast phenotype. CONCLUSIONS These data show that BPH reactive stroma is fundamentally different from normal prostate fibromuscular stroma and is typified by the emergence of a reactive stroma myofibroblast phenotype. This reactive stroma pattern correlated spatially with IL-8 elevation in adjacent epithelium. Additionally, IL-8 induced expression of myofibroblast markers in human prostate fibroblasts in vitro. These results suggest that IL-8 acts as a regulator of BPH reactive stroma and is therefore a potential therapeutic target.

Keratinocyte-Derived Chemokine Induces Prostate Epithelial Hyperplasia and Reactive Stroma in a Novel Transgenic Mouse Model

Interleukin‐8 (IL‐8) is upregulated in fibrotic and malignant diseases and is a key mediator of proliferative responses. Elevated IL‐8 was recently correlated with benign prostatic hyperplasia epithelium and a myofibroblast reactive stroma. Thus, we sought to determine whether overexpressed IL‐8 and keratinocyte‐derived chemokine (KC), the functional murine homolog of IL‐8, induce prostate epithelial hyperplasia and a reactive phenotype.

Overexpression of the β Subunit of Human Chorionic Gonadotropin Promotes the Transformation of Human Ovarian Epithelial Cells and Ovarian Tumorigenesis

Ovarian carcinoma is the most lethal gynecologic malignancy, however underlying molecular events remain elusive. Expression of human chorionic gonadotropin β subunit (β-hCG) is clinically significant for both trophoblastic and nontrophoblastic cancers; however, whether β-hCG facilitates ovarian epithelial cell tumorigenic potential remains uncharacterized. Immortalized nontumorigenic ovarian epithelial T29 and T80 cells stably overexpressing β-hCG were examined for alterations in cell cycle and apoptotic status by flow cytometry, expression of proteins regulating cell cycle and apoptosis by Western blot, proliferation status by MTT assay, anchorage-independent colony formation, and mouse tumor formation. Immunoreactivity for β-hCG was evaluated using mouse xenografts and on human normal ovarian, fallopian tube, endometrium, and ovarian carcinoma tissues. T29 and T80 cells overexpressing β-hCG demonstrated significantly increased proliferation, anchorage-independent colony formation, prosurvival Bcl-X(L) protein expression, G2-checkpoint progression, elevated cyclins E/D1 and Cdk 2/4/6, and decreased apoptosis. Collectively, these transformational alterations in phenotype facilitated increased xenograft tumorigenesis (P < 0.05). Furthermore, β-hCG immunoreactivity was elevated in malignant ovarian tumors, compared with normal epithelial expression in ovaries, fallopian tube, and endometrium (P < 0.001). Our data indicate that elevated β-hCG transforms ovarian surface epithelial cells, facilitating proliferation, cell cycle progression, and attenuated apoptosis to promote tumorigenesis. Our results further decipher the functional role and molecular mechanism of β-hCG in ovarian carcinoma. β-hCG may contribute to ovarian cancer etiology, which introduces a new therapeutic intervention target for ovarian cancer.