A mathematical model for predicting putative association between E2/T ratio and the development of benign prostate hyperplasia in rats.

Benign prostatic hyperplasia (BPH) develops more likely with increasing age and changing serum concentrations of circulating estradiol (E2) and/or testosterone (T). In this study, we explored the relationship between serum E2/T ratio and BPH risk in rats by fitting a mathematical model. A total of 176 rats were randomized to one of the following treatment groups: normal control, castrated control, and 20 more groups of castrated animals treated with increasing dose combinations of T and E2, once daily for 30 days. Serial blood samples were obtained to determine serum T and E2 levels by magnetic bead enzyme-linked immunosorbent assay. Prostate tissue was taken to measure prostate volume. MATLAB software was used to simulate the relationship between prostate/body weight ratio (PBR) and E2/T ratio with a mathematical equation. The values of PBR, E2 and T in the treatment groups were significantly higher than those in the control groups. Stepwise regression showed that PBR was a function of E2 and T. PBR = -0.1782 + 0.0081 E2 + 0.063 T - 0.6 × 10-5 E22 - 0.28 × 10-3 T2. E2/T ratio change may be one of the risk factors for PBR, which is associated with the development of BPH.

[Correlation of prostate-specific antigen with the progression and metastasis of human prostate cancer].

Prostate-specific antigen (PSA) is a biomarker for the diagnosis and management of prostate cancer and involved in the development of prostate cancer and/or its progression from the localized to the metastatic stage. This review presents an overview of the roles of PSA in promoting the progression and metastasis of human prostate cancer and its underlying mechanisms, including its serine protease activity, interaction with the cellular membrane receptor, and suppression of specific immune responsiveness, and also points out some of the key problems to be solved.

Oral exposure of low-dose bisphenol A promotes proliferation of dorsolateral prostate and induces epithelial-mesenchymal transition in aged rats.

Bisphenol A (BPA) is a well-known endocrine disruptor compound reported to have prostate toxicity. This study aimed to assess the effect of BPA on the proliferation of dorsolateral prostate (DLP) and the expression of epithelial-mesenchymal transition (EMT)-related genes in aged rats. Male aged SD rats were treated with BPA (10.0, 30.0, and 90.0 µg/kg i.g., daily) or vehicle (i.g., daily) for 3 months. Treatment with BPA resulted in increased the expression of PCNA, DLP weight and DLP epithelial height compared with the control group (P < 0.01); such effects were more obvious at higher BPA doses. 90 µg/kg BPA significantly increased the estrogen to androgen ratio (P < 0.05). The EMT chip showed the BPA induced upregulation of vimentin, Snail, Twist1, and transforming growth factor beta 1, as well as the downregulation of E-cadherin in the DLP. Immunohistochemical data showed that the expression of vimentin, estrogen receptor subtypes, and androgen receptor increased and the expression of E-cadherin decreased in 30 and 90 µg/kg BPA groups. It was concluded that environmental exposure to low doses of BPA might promote the proliferation of DLP in aged rats by increasing the estrogen to androgen ratio and inducing EMT.

Effect of Mono-2-ethyhexyl Phthalate on DNA Methylation in Human Prostate Cancer LNCaP Cells.

OBJECTIVE: To evaluate whether mono (2-ethylhexyl) phthalate (MEHP) affects genomic DNA methylation and the methylation status of some specific genes such as patched gene (PTCH) and smoothened gene (SMO) in LNCaP cells. METHODS: LNCaP cells were treated with MEHP (0, 1, 5, 10, and 25 µmol/L) for 3 days. An ELISA assay was preformed to detect genomic methylation, including 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) content. A pyrosequencing assay was applied to assess DNA methylation in PTCH and SMO gene promoters. The correlation between DNA methylation and gene expression was assessed. RESULTS: The proportion of cytosines with 5-mC methylation in LNCaP cells was significantly decreased by MEHP (1, 5, 10, and 25 µmol/L) in a dose-dependent manner (P < 0.01). For genes in the Hedgehog pathway, there was no significant MEHP concentration-dependent difference in the DNA methylation of PTCH and SMO. CONCLUSION: MEHP might affect the progression of prostate cancer through its effect on global DNA methylation.

[Gene regulation of prostaglandin synthase and prostate diseases].

Prostaglandin synthase (PGS) can catalyze the production of various types of prostaglandins and regulate the expression levels of related substances. The regulation mechanisms of the PGS gene are closely related with the occurrence and development of prostate diseases. However, few studies are reported on the regulation mechanisms of PGS in prostatic diseases, such as benign prostatic hyperplasia (BPH) and prostate cancer (PCa), or on the relationship between PGS gene regulation and prostate diseases. This review aims to analyze their correlation and provide some ideas for the prevention and control of BPH and PCa by intervention of the prostaglandin synthase regulatory pathway.

[Research progress in mechanism of traditional Chinese medicine treatment of polycystic ovary syndrome].

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder, which is characterized by hyperandrogenism, insulin resistance and chronic anovulation, and has become a serious threat to the health of adolescents and women of childbearing age.At present,lowering androgen, improving insulin resistance and inducing ovulation are the main methods adopted by doctors to treat the disease, but the adverse reactions of the western medicine and the long-term treatment are hard to be accepted by the patients. PCOS treated by traditional Chinese medicine has achieved a certain effect in recent years.Traditional Chinese medicine is relatively safe and has more effect in many links and targets in improving the symptom of endocrine and metabolic disorder in patients with PCOS. This paper expounds the traditional Chinese medicine pathogenesis of PCOS through clinical and experimental aspects of the literature research：correcting endocrine hormone disorder,the effects of the expression of gene and regulatory factors,improving insulin resistance,correcting lipid metabolic disorder,improving the pregnancy outcome and improving ovarian morphology to summarize the treatment of traditional Chinese medicine in PCOS research results in recent years.

Pharmacodynamic study of 131I-labeled CA215 antibody on an animal model of estrogen-resistant OC-3-VGH ovarian cancer.

The aim of the present study was to explore the inhibitory effect of 131I-labeled ovarian cancer antigen 215 (131I-CA215) antibody on human OC-3-VGH ovarian cancer. A subcutaneous transplanted tumor model of estrogen-resistant human OC-3-VGH ovarian cancer in nude mice was established. The model mice were randomly divided into seven groups, which were the negative control (NC), positive control (PC; 60 mg/kg cyclophosphamide), high-dose CA215 antibody (HA; 10 mg/kg), low-dose CA215 antibody (LA; 2 mg/kg), high-dose 131I-CA215 antibody (131I-HA; 10 mg/kg + 125 µCi), medium-dose 131I-CA215 antibody (131I-MA; 6 mg/kg + 75 µCi) and low-dose 131I-CA215 antibody (131I-LA; 2 mg/kg + 25 µCi) groups. Each group received intraperitoneal administration for 14 consecutive days. At 24 h after the final administration, the tumor was removed and weighed to calculate the tumor inhibition rate (TIR) and the relative tumor increase rate (T/C). Compared with the NC group, the HA group, as well as the 31I-HA and 131I-MA antibody groups, exhibited significantly inhibited tumor growth. The relative T/C values were 54, 30 and 48%, respectively, and the TIRs were 33.59, 64.89 and 45.80%, respectively. All differences were statistically significant. The difference between the HA and 131I-HA groups also presented statistical significance. CA215 and 131I-CA215 antibodies can markedly inhibit OC-3-VGH ovarian cancer. The high-dose 131I-CA215 antibody demonstrated a clear synergetic effect.

Studies on the characteristics and mechanisms of testicular toxicity induced by Hydroxyurea.

OBJECTIVE: Apoptosis plays a dominant role in both spontaneous spermatogenesis and germ cell death. This study was aimed to investigate the functions of related genes in testicular germ cell death induced by Hydroxyurea (HU). METHOD: Wild-type (WT) and FasL transgenic (TG) DBA/C57BL mice were intraperitoneal injected with 400 mg/kg HU. Twelve hours later, testes were collected. Histomorphology of testis was observed by staining with Periodic Acid Schiff (PAS). Apoptosis was assessed by TUNEL assay. mRNA and protein levels of related genes were evaluated by quantitative RT-PCR and Western blot, respectively. RESULTS: The 2 × 2 factorial design comparative experiments between the WT and TG mice showed that the TG mice exhibited a higher basal apoptotic index. The basal mRNA levels of Fas and FasL and protein levels of Fas, FasL, Caspase-3, Caspase-8 and Caspase-9 in the TG mice were also higher than that in the WT mice. Twelve hours after injection of HU, the testicular tubules exhibited no significantly morphological changes but apoptosis index remarkably increased in both the WT and TG mice, with the latter having the higher amplitude. Although, HU up-regulated the mRNA of apoptosis-related genes, such as Fas and FasL, in both the TG and WT mice, the increased amplitude was more obvious in the TG mice. By Western blot analysis, apoptosis-related proteins Fas, FasL Caspase-3, Caspase-8 and Caspase-9 were significantly increased in both the WT and TG mice, with the TG mice exhibiting a greater up-regulation. CONCLUSION: Germ cell apoptosis induced by the HU treatment may be related to the FasL-mediated signal transduction pathway.

The alteration of inflammatory markers and apoptosis on chronic prostatitis induced by estrogen and androgen.

PURPOSE: The age-related decline of the testosterone-to-estrogen (T-to-E2) ratio in serum is associated with the increased prevalence of prostatic inflammation. The goal of the study was to induce prostatic inflammation with E2 and androgen treatment and to explore the inflammatory markers and apoptosis on prostatitis. METHODS: Castrated SD rats were treated with E2 and different doses of androgens to achieve an elevated concentration of E2 and a wide range of the androgen-to-E2 ratio in serum. Inflammatory markers TNF-α, COX-2 and MIP-1α were immunohistochemically stained. Apoptosis detection was evaluated by TUNEL staining. E2, T and DHT concentrations in serum were measured, and the relative weight of the prostate and seminal vesicles were determined. RESULTS: T was anti-inflammatory at the doses which normalized or over stimulated the growth of the prostate and seminal vesicles. Experimentally, prostatitis induced by E2 alone increased the prostatic levels of the inflammatory markers TNF-a, COX-2 and MIP-1a. As signs of anti-estrogenic actions, androgens dose-dependently decreased the expression of TNF-α, COX-2 and MIP-1α. Prostatitis induced by E2 alone caused extensive apoptosis in the castrate-resistant cells and E2-induced apoptosis occurred dependently of T manipulation. CONCLUSIONS: Estrogen-alone-induced inflammatory response could promote the expression of inflammatory markers; however, T supplementation reduces the expression of inflammatory markers and E2-induced apoptosis occurs dependently on T manipulation in prostatitis.

Cancer immunotherapy using a potent immunodominant CTL epitope.

Immunotherapy has emerged as a promising approach that can be used in conjunction with conventional chemotherapy and radiotherapy to further improve the survival rate of patients with advanced cancer. We have recently shown in previous studies that chemotherapy and radiation therapy can alter the tumor microenvironment and allow intratumoral vaccination to prime the adaptive immune system leading to the generation of antigen-specific cell-mediated immune responses. Here, we investigated whether intratumoral injection of a foreign immunodominant peptide (GP33) and the adjuvant CpG into tumors following cisplatin chemotherapy could lead to potent antitumor effects and antigen-specific cell-mediated immune responses. We observed that treatment with all three agents produced the most potent antitumor effects compared to pairwise combinations. Moreover, treatment with cisplatin, CpG and GP33 was able to control tumors at a distant site, indicating that our approach is able to induce cross-presentation of the tumor antigen. Treatment with cisplatin, CpG and GP33 also enhanced the generation of GP33-specific and E7-specific CD8+ T cells and decreased the number of MDSCs in tumor loci, a process found to be mediated by the Fas-FasL apoptosis pathway. The treatment regimen presented here represents a universal approach to cancer control.

[Categories and characteristics of BPH drug evaluation models: a comparative study].

Benign prostatic hyperplasia (BPH) is a worldwide common disease in men over 50 years old, and the exact cause of BPH remains largely unknown. In order to elucidate its pathogenesis and screen effective drugs for the treatment of BPH, many BPH models have been developed at home and abroad. This article presents a comprehensive analysis of the categories and characteristics of BPH drug evaluation models, highlighting the application value of each model, to provide a theoretical basis for the development of BPH drugs.

[Establishment of an in vitro screening model for steroid 5 alpha-reductase inhibitors with the microplate reader].

OBJECTIVE: To establish an in vitro screening model for steroid 5 alpha-reductase inhibitors using the microplate reader. METHODS: Steroid 5 alpha-reductase was obtained from the liver of female rats, an in vitro screening model for steroid 5 alpha-reductase inhibitors established using the 96-well plate and microplate reader after determination of the enzymatic activity, and the reliability of the model verified with the known 5 alpha-reductase inhibitors epristeride and finasteride. Added to the 96-well plate were the final concentrations of testosterone (0-40 micromol/L), NADPH (22 micromol/L), epristeride (0-60 nmol/L) or finasteride (0-60 nmol/ L) and steroid 5 alpha-reductase (20 microl), the total volume of each well adjusted to 200 microl with Tris-Hcl buffer. The 96-well plate was placed in the microplate reader, mixed and incubated at 37 degrees C, followed by detection of the A340nm value at 0 and 10 min and analysis of the data. RESULTS: The Km value of steroid 5 alpha-reductase was 3.794 micromol/L, with a Vmax of 0.271 micromol/(L. min). The Ki of epristeride was 148.2 nmol/L, with an IC50 of 31.5 nmol/L, and the enzymatic reaction kinetic curve suggested that epristeride was an uncompetitive enzyme inhibitor. The Ki of finasteride was 158. 8 nmol/L, with an IC50 of 13.6 nmol/L. The enzymatic reaction kinetic curve showed that both epristeride and finasteride were competitive enzyme inhibitors, similar to those reported in the published literature. CONCLUSION: A screening model was successfully established, which could rapidly and effectively screen steroid 5 alpha-reductase inhibitors in vitro.

Oral exposure to low-dose bisphenol A aggravates testosterone-induced benign hyperplasia prostate in rats.

The declining level of androgen during aging, associated with an inclining level of estrogen, has been hypothesized to be important in the development of benign prostatic hyperplasia (BPH). Within physiologic range, increasing estrogen levels can stimulate prostate to develop and permanently increase prostate size. As an estrogenic endocrine disruptor, bisphenol A (BPA) might be stimulatory to prostate development. We further hypothesized that low dose BPA could induce hyperplasia prostate to proliferate and aggravate the symptom of BPH in male SD rats. BPH was induced by testosterone and then treated with BPA (10, 30, or 90 µg/kg, i.g., daily), 17ß-estradiol (E(2); 50.0 µg/kg, s.c., daily), or vehicle for 4 weeks. We found that weight and volume in rats treated with low dose BPA (10 µg/kg) was higher than that of model control, and BPA significantly increased the relative weight of prostate (p < 0.01). For prostate lobes, BPA 10 µg/kg/day significantly increased relative weight of ventral prostate (VP), weight and relative weight of dorsolateral prostate (DLP) (p < 0.05). And histopathology results showed that height of epithelial cell (HEC) of VP and DLP in BPA group were significantly higher than that of model control (p < 0.01). BPA could also decrease testosterone level and increase prostate-specific antigen level. E(2) treatment also showed an obvious effect on relative weight of VP and DLP, HEC, and hormone levels. We concluded that environment exposure to low dose of BPA may induce prostate to proliferate and aggravate testosterone-induced benign hyperplasia prostate in rats.

Mitosis orientation in prostate epithelial cells changed by endocrine effect.

AIM: The aim of the present study was to investigate the effect of androgen and estrogen on mitosis orientation in the prostate epithelial cells of male rats. METHODS: Castrated rats were treated with a single injection of testosterone propionate (TP) or benzogynestry (E2). There were 8 rats in the control group and TP-treated or E2-treated group. Prostate, liver, a specimen of skin, and a segment of the jejunum and colon were removed after the corresponding treatment. The results were observed through immunohistochemistry and iron hematoxylin-eosin staining. RESULTS: All mitoses found in the prostate epithelial cells of castrated rats with TP were oriented parallel to the basement membrane; however, mitoses found in the prostate epithelial cells of castrated rats in E2 and the control group were oriented perpendicular to the basement membrane. TP treatment resulted in marked changes in mitosis orientation in the prostate epithelial cells. Bromodeoxyuridine-labeled positive cells could be seen throughout the stroma and prostate epithelial cells with an injection of TP; however, the positive cells could only be seen in the stroma of prostate with an injection of E2, and the positive cells could hardly be seen in the control group. CONCLUSION: We found a novel effect of TP in the prostate as a marked change of mitosis orientation in prostate epithelial cells.

Effects of gestrinone on uterine leiomyoma and expression of c-Src in a guinea pig model.

AIM: To investigate the effect of gestrinone on uterine leiomyomas and the expression of c-Src, estradiol receptors (ER), and progesterone receptors (PR) in a guinea pig model. METHODS: After being oophorectomized, the guinea pigs were allocated into random groups. The model group was treated with estradiol benzoate (E2) for 16 weeks. In the gestrinone-treated groups, the animals were treated with E2 for 6 weeks in advance, and then in combination with gestrinone for 10 weeks. Histological examination was performed to evaluate whether there were leiomyoma features in the animals. The protein levels of c-Src, phospho-( 416)Src, ER, and PR were assayed by Western blotting and an immunohistochemical method. RESULTS: Morphological changes were observed in the myometrium of the guinea pig model, including an increase of uterine weights, proliferation of uterine smooth muscles, and the formation of nodules. High protein levels of c-Src, phospho- 416Src, ER, and PR were observed in the myometrium of the guinea pig model. In the gestrinone-treated group, there were no nodules observed. The histological features of the myometrium were similar to that of the control group. Low protein levels of c-Src, phospho-(416 )Src, ER, and PR were observed in the gestrinonetreated group. CONCLUSION: The upregulation of c-Src and phospho-(416 )Src indicated that the activity of c-Src is augmented in the uterine leiomyoma model. c-Src was associated with the formation of uterine leiomyomas in the model, and gestrinone markedly suppressed the growth of uterine leiomyomas in the model. Gestrinone inhibited not only the protein expression of ER and PR, but also c-Src and the autophosphorylation of c-Src in the guinea pig leiomyoma model.

Differential metastasis-associated gene analysis of prostate carcinoma cells derived from primary tumor and spontaneous lymphatic metastasis in nude mice with orthotopic implantation of PC-3M cells.

The purpose of these studies was to explore the genes associated with invasion and metastasis of human prostatic carcinoma line PC-3M in nude mice. After PC-3M cells were inoculated in orthotopic site (prostate) in male nude mice for two months, tumor cells were isolated from primary tumor and lymph node metastasis in the same mouse, respectively. Cell invasion and adhesion ability in vitro were first compared between two cell lines. Then human metastasis-related genes differentially expressed between them were analyzed by utilizing cDNA microarray technique. The in vitro cell invasion and adhesion potential of tumor cells from lymph node metastasis was significantly higher than those from primary tumor, Metastasis-related genes differentially expressed between those two cell lines were identified, all of them were up-regulated in the tumor cells from lymph node metastasis and could be categorized as: (1) genes encoding cellular matrix-degrading proteolytic enzyme including cathepsin and MMP; (2) genes encoding transcription factors; (3) genes related to heterotypic adhesion of tumor cells; (4) genes encoding cell surface receptors. Moreover, Four genes were chosen for semi-quantitative RT-PCR analysis, they showed a consistent expression pattern with that of cDNA microarray analysis. We concluded that the lymph node metastasis in nude mice given an injection of PC-3M cells in the prostate is a selective process favoring the survival and growth of a special subpopulation derived from primary tumor with specific genetic alterations, which may play a pivotal role in the metastasis of prostate cancer. Identification and further characterization of these genes may allow a better understanding of lymphatic metastasis in prostate carcinoma.

[DNA damages of liver cells and expressions of DNA damage repair genes in rats exposed to vinyl chloride monomer].

OBJECTIVE: To study DNA damages of liver cells in rats exposed to vinyl chloride monomer (VCM), and the expressions of DNA damage repair enzymes including O(6)-methyl guanine-DNA methyl transferase (MGMT), X-ray repair cross-complementing group 1 (XRCC1) and X-ray repair cross-complementing group 3 (XRCC3); and to explore the repair mechanism of DNA damage induced by VCM. METHODS: Rats were exposed to VCM by intraperitoneal injection. DNA damages were detected by single cell gel electrophoresis (comet assay). The expressions of DNA damage repair enzymes were measured by immunohistochemical methods. RESULTS: The percentages of comet cells in low, moderate, and high dose groups (11.75%, 12.38%, and 17.63%, respectively) were greater than that of control (5.67%). The latter two groups were significantly different from that of control (P < 0.05, P < 0.01). The expressions of MGMT and XRCC1 decreased, and XRCC3 increased with the dose of VCM increased. DNA damage was correlated with the expression of XRCC3 (r = 0.438, P = 0.067). CONCLUSION: VCM can cause DNA damage of liver cells with dose-response relationship. DNA damage repair enzymes take part in the repairing of DNA damage induced by VCM.

[Establishment of prostatic hyperplasia model with castration beagle canines].

OBJECTIVE: To establish a prostatic hyperplasia model with Beagle canines. METHODS: Twenty-four two-year-old male Beagle canines were divided into treatment and control groups at random and were administrated testosterone propionate (TP) through intramuscular injection two months after castration. Three treatment groups were given 0.8, 2.5 and 7.5 mg/kg TP respectively, and the control was given the same volume of vehicle. Two months later, half of the animals were killed and the serum and prostate were prepared. After the wet weight and volume of prostate were measured, the dihydrotestosterone (DHT) level of serum and prostate were detected with DHT radioimmunoassay (RIA) kit, and paraffine section from canine prostate was stained by the HE methods. Pictures were taken by digital camera under microscope, and all the pictures were analyzed by computer for epithelial cell height and acinar luminal area of prostate with micro image analysis software. The canine prostate volume was measured with ultrasonic diagnosis instrument before castration, at two months after castration and at two months after being given TP. RESULTS: The ultrasonic results showed that the prostate volumes of all the canines were smaller at two months after castration than before castration (P < 0.05), and after having been administrated TP for two months, and the prostate volumes of all treatment groups were larger than those of the control group (P < 0.01). The wet weight of the prostate of the treatment group was higher than that of the control group (P < 0.05), and both had dose-dependent relationship. The DHT level of serum and prostate of the canines became higher with the increase of TP dose. The results of micro image analysis showed that the acinar luminal area of prostate was enlarged, and the epithelial cell height increased with larger dose of TP. CONCLUSIONS: It is practicable to establish prostatic hyperplasia model in Beagle canines after two months of TP administration.