Effect of human seminal fluid on production of messenger ribonucleic acid for metalloproteinase 2 and metalloproteinase 9 in cervical epithelial carcinoma cells

The Female Response to Seminal Fluid

Seminal fluid is often assumed to have just one function in mammalian reproduction, delivering sperm to fertilize oocytes. But seminal fluid also transmits signaling agents that interact with female reproductive tissues to facilitate conception and .pregnancy. Upon seminal fluid contact, female tissues initiate a controlled inflammatory response that affects several aspects of reproductive function to ultimately maximize the chances of a male producing healthy offspring. This effect is best characterized in mice, where the female response involves several steps. Initially, seminal fluid factors cause leukocytes to infiltrate the female reproductive tract, and to selectively target and eliminate excess sperm. Other signals stimulate ovulation, induce an altered transcriptional program in female tract tissues that modulates embryo developmental programming, and initiate immune adaptations to promote receptivity to implantation and placental development. A key result is expansion of the pool of regulatory T cells that assist implantation by suppressing inflammation, mediating tolerance to male transplantation antigens, and promoting uterine vascular adaptation and placental development. Principal signaling agents in seminal fluid include prostaglandins and transforming growth factor-β. The balance of male signals affects the nature of the female response, providing a mechanism of ‟cryptic female choiceˮ that influences female reproductive investment. Male-female seminal fluid signaling is evident in all mammalian species investigated including human, and effects of seminal fluid in invertebrates indicate evolutionarily conserved mechanisms. Understanding the female response to seminal fluid will shed new light on infertility and pregnancy disorders and is critical to defining how events at conception influence offspring health.

Seminal plasma enhances cervical adenocarcinoma cell proliferation and tumour growth in vivo

Cervical cancer is one of the leading causes of cancer-related death in women in sub-Saharan Africa. Extensive evidence has shown that cervical cancer and its precursor lesions are caused by Human papillomavirus (HPV) infection. Although the vast majority of HPV infections are naturally resolved, failure to eradicate infected cells has been shown to promote viral persistence and tumorigenesis. Furthermore, following neoplastic transformation, exposure of cervical epithelial cells to inflammatory mediators either directly or via the systemic circulation may enhance progression of the disease. It is well recognised that seminal plasma contains an abundance of inflammatory mediators, which are identified as regulators of tumour growth. Here we investigated the role of seminal plasma in regulating neoplastic cervical epithelial cell growth and tumorigenesis. Using HeLa cervical adenocarcinoma cells, we found that seminal plasma (SP) induced the expression of the inflammatory enzymes, prostaglandin endoperoxide synthase (PTGS1 and PTGS2), cytokines interleukin (IL) -6, and -11 and vascular endothelial growth factor-A(VEGF-A). To investigate the role of SP on tumour cell growth in vivo, we xenografted HeLa cells subcutaneously into the dorsal flank of nude mice. Intra-peritoneal administration of SP rapidly and significantly enhanced the tumour growth rate and size of HeLa cell xenografts in nude mice. As observed in vitro, we found that SP induced expression of inflammatory PTGS enzymes, cytokines and VEGF-A in vivo. Furthermore we found that SP enhances blood vessel size in HeLa cell xenografts. Finally we show that SP-induced cytokine production, VEGF-A expression and cell proliferation are mediated via the induction of the inflammatory PTGS pathway.

Activation of telomerase by seminal plasma in malignant and normal cervical epithelial cells

Seminal fluids are involved in the development of cervical cancer but the underlying mechanism is unclear. Because cellular transformation requires telomerase activation by expression of the telomerase reverse transcriptase (hTERT) gene, we examined the role of seminal fluids in telomerase activation. Significantly elevated hTERT mRNA and telomerase activity were observed in cervical cell lines (HeLa, SiHa and Caski) treated with seminal plasma. Normal cervical epithelial cells expressed minimal levels of hTERT mRNA and telomerase activity, and seminal plasma substantially enhanced both expression and activity. The hTERT promoter activity was similarly increased in seminal plasma-treated HeLa cells and this effect was closely correlated with increased Sp1 expression and binding to the hTERT promoter. Cyclooxygenase-2 (COX-2) was simultaneously increased in HeLa cells exposed to seminal plasma, and blockade of COX-2 induction abolished seminal plasma stimulation of the hTERT promoter activity, hTERT expression and telomerase activity. Prostaglandin E2 (PGE2) mimics the effect of seminal plasma, stimulating Sp1 expression, enhancing Sp1 occupancy on the hTERT promoter and promoter activity. Moreover, tumour growth was robustly enhanced when HeLa cells together with seminal plasma were injected into nude-mice. Taken together, seminal plasma stimulates COX-2-PGE2-Sp1-dependent hTERT transcription, which provides insights into the putative mechanism underlying telomerase activation in cervical epithelial and cancer cells.

Descriptive evidence that risk profiles for cervical intraepithelial neoplasia 1, 2, and 3 are unique

OBJECTIVE

This study aimed to estimate if risk factor profiles for histologically confirmed cervical intraepithelial neoplasia (CIN) 2 lesions differ from those for CIN 1 or 3.

METHODS

A total of 2,055 women positive for high-risk human papillomavirus, with a minimum of five cervical biopsies, were enrolled in the Shanxi Province Cervical Cancer Screening Study II. We evaluated risk factor profiles for CIN 2 in comparison with CIN 1 and 3. Polytomous logistic regression was used to generate odds ratios and corresponding 95% confidence intervals and to test for differences in odds ratios across histologic grades.

RESULTS

The risk for CIN 3 associated with three or more pregnancies and sexual intercourse within 4 months of childbirth was higher than that for CIN 2 (P(difference) = 0.02 and 0.0007, respectively). Significant differences in the associations of age groups with CIN 1 and 2 were observed, such that there were positive associations with CIN 2 but none for CIN 1. There was no difference in the association of number of sexual partners or reported number of abortions between CIN 1 and 2 or between CIN 3 and 2.

CONCLUSIONS

In our study, the patterns of risk factor profiles for CIN 1, 2, and 3 were unique. Conventional grouping of CIN 2 with 3 for analysis of risk factors may need revisiting.

Seminal plasma promotes the expression of tumorigenic and angiogenic genes in cervical adenocarcinoma cells via the E-series prostanoid 4 receptor

E-series prostanoid (EP)4 receptor is up-regulated in numerous cancers, including cervical carcinomas, and has been implicated in mediating the effects of prostaglandin (PG)E(2) in tumorigenesis. In addition to regulation by endogenously biosynthesized PGE(2), neoplastic cervical epithelial cells in sexually active women may also be regulated by PGs present in seminal plasma. In this study, we investigated the signal transduction pathways mediating the role of seminal plasma and PGE(2) in the regulation of tumorigenic and angiogenic genes via the EP4 receptor in cervical adenocarcinoma (HeLa) cells. HeLa cells were stably transfected with EP4 receptor in the sense orientation. Seminal plasma and PGE(2) signaling via the EP4 receptor induced the activation of cyclooxygenase (COX)-2 and vascular endothelial growth factor (VEGF) promoters, expression of COX-2 and VEGF mRNA and protein, and secretion of VEGF protein into the culture medium. Treatment of HeLa cells with seminal plasma or PGE(2) also rapidly induced the phosphorylation of ERK1/2 via the EP4 receptor. Preincubation of cells with a specific EP4 receptor antagonist (ONO-AE2-227) or chemical inhibitors of epidermal growth factor receptor (EGFR) tyrosine kinase or MAPK kinase or cotransfection of cells with dominant-negative mutant cDNA targeted against the EGFR, serine/threonine kinase Raf, or MAPK kinase abolished the EP4-induced activation of COX-2, VEGF, and ERK1/2. Therefore, we have demonstrated that seminal plasma and PGE(2) can promote the expression of tumorigenic and angiogenic factors, in cervical adenocarcinoma cells via the EP4 receptor, EGFR, and ERK1/2 signaling pathways.

Seminal fluid enhances replication of human T-cell leukemia virus type 1: implications for sexual transmission

Seminal fluid enhanced human T-cell leukemia virus type 1 (HTLV-1) infection by transactivating the HTLV-1 long terminal repeat promoter, which is chromosomally integrated in a cell-type-dependent manner. Our data may indicate a potential role for seminal fluid in the sexual transmission of HTLV-1 and imply complex features of regulation of HTLV-1 expression.