In-vitro generation of follicle-like structures from human germ cell-like cells derived from theca stem cell combined with ovarian somatic cells.

BACKGROUND: The objective of this study was to induce the differentiation of human theca stem cells (hTSCs) into germ cell-like cells (hGCLCs) and assess their developmental progression following in vitro 3D culture with ovarian somatic cells within the follicle-like structures. To achieve this, the hTSCs were isolated from small antral follicles of three patients of varying ages and were then seeded in a differentiation medium for 40 days. The differentiated hGCLCs were subsequently aggregated with somatic ovarian cells (cumulus cells and hTSCs) in a ratio of 1:10 and cultured in a growth medium in a suspension culture dish. In addition to examining the morphologies, sizes, and viabilities of the differentiated hGCLCs, this study also analyzed the expression of DAZL and GDF9 proteins within the follicle-like structures. RESULTS: After 12 days, the hTSCs began to differentiate into hGCLCs, with their shapes changing from spindle-shaped to spherical. The sizes of hGCLCs increased during the differentiation period (from 25 µm to 50 µm). The survival rate of the hGCLCs after differentiation and in vitro development in primordial follicle-like structures was 54%. Unlike hTSCs, which did not express the DAZL protein, the hGCLCs and follicle-like structures successfully expressed DAZL protein (P-value < 0.05). However, hGCLCs poorly expressed the GDF9 protein. Further, the culture of hGCLCs in primordial follicle-like structures significantly increased GDF9 expression (P-value < 0.05). CONCLUSION: In conclusion, our study demonstrated that 3D cultures with ovarian somatic cells in follicle-like structures caused the successful differentiation of reproducible hGCLCs from hTSCs derived from three patients of different ages. Moreover, this method not only enhanced the in vitro development of hGCLCs but also presented a novel approach for co-culturing and developing in vitro oocyte like cells, ultimately leading to the production of artificial follicles.

The impact of sex on susceptibility to systemic lupus erythematosus and rheumatoid arthritis; a bioinformatics point of view.

The unknown etiology of systemic autoimmune diseases, such as Systemic Lupus Erythematosus (SLE) and Rheumatoid Arthritis (RA), with a remarkable predominance of female, have prompted many researchers for unveiling the precise molecular mechanisms involved in this gender bias. In fact, depending on hormones and transcribed genes from sex chromosomes, at least, the initial mechanisms involved in pathogenesis might differ largely. With the aim of elucidating the above mechanisms, we have tried to specify the differentially expressed genes (DEGs) extracted from microarray libraries from both female and male SLE and RA patients. Subsequently, the androgen and estrogen receptor elements (ARE and ERE) among differentially expressed transcription factors (TFs) and the DEGs located on X or Y chromosomes have been determined. Moreover, the pathways regarding the common DEGs in both sexes are enriched. Our data revealed several ARE and ERE-containing genes (LCN2, LTF, RPL31, RPL9, RPS17, RPS24, RPS27L, S100A8, ABCA1, HIST1H2BD, ISG15, MAFB, GNLY, EVL, and HDC) to be associated with the related autoimmune disease and sex. Also, two DEGs (KDM5D and RPS4Y1) in SLE patients were determined to be on Y chromosome with one had been proved to be associated with autoantigens in SLE. Altogether, our data showed a number of plausible pathways in both autoimmune conditions together with the relevance of several sex-related genes in the mentioned diseases pathogenesis.

Gene editing technology for improving life quality: A dream coming true?

The fact that monogenic diseases are related to mutations in one specific gene, make gene correction one of the promising strategies in the future to treat genetic diseases or alleviate their symptoms. From this perspective, and along with recent advances in technology, genome editing tools have gained momentum and developed fast. In fact, clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9), transcription activator-like effector nucleases (TALENs), and zinc-finger nucleases (ZFNs) are regarded as novel technologies which are able to correct a number of genetic aberrations in vitro and in vivo. The number of ongoing clinical trials employing these tools has been increased showing the encouraging outcomes of these tools. However, there are still some major challenges with respect to the safety profile and directed delivery of them. In this paper, we provided updated information regarding the history, nature, methods of delivery, and application of the above-mentioned gene editing tools along with the meganucleases (an older similar tool) based on published in vitro and in vivo studies and introduced clinical trials which employed these technologies.

AGS cell line xenograft tumor as a suitable gastric adenocarcinoma model: growth kinetic characterization and immunohistochemistry analysis.

OBJECTIVES: Gastric cancer is the third leading cause of cancer-related death worldwide. The overall survival rate of patients is poor because gastric cancers are usually diagnosed at the late stages. Therefore, further research is needed and appropriate research tools are required to develop novel therapeutic approaches. MATERIALS AND METHODS: Eight female athymic nude mice with a C57BL/6 background were used in this study. AGS cells were inoculated into the flank. The tumor volumes were calculated and growth curves were drawn. When the volume of the tumors reached 1000 mm3, the animals were humanely euthanized with CO2 gas. After harvesting, tumors were analyzed with Hematoxylin and Eosin (H&E) and immunohistochemistry (IHC). A pathologist confirmed tumor entity through H&E staining. Tumors were evaluated for expression of HER-2, P53, Ki-67, CD34, cytokeratin 8 (CK8), vimentin, estrogen receptor (ER), and progesterone receptor (PR) utilizing immunohistochemistry. RESULTS: The tumor take rate was 62.5%, mean doubling time was 40.984 d, and the latency period was 30.62 days. The H&E staining results showed highly malignant hyperchromatin epithelial cells. IHC assessment showed the mutation status of P53 gene. The expression score of the CK8 protein in the tumor cells was +3. Vimentin protein was not expressed and changes in mesenchymal phenotype were not observed. Ki-67 IHC indicated that the proliferation rate was >43% and angiogenesis was defined as high MVD. CONCLUSION: The respective AGS xenograft model provides an opportunity to understand the pattern of tumor growth as well as to evaluate new gastric cancer therapies in in vivo studies.

Long­term behavioral, histological, biochemical and hematological evaluations of amyloid beta­induced Alzheimer's disease in rat.

Alzheimer's disease (AD) is a mental impairment and neural degeneration which causes progressive loss of memory and cognitive functions. This age­dependent illness is associated with extracellular amyloid plaques accumulation and twisted neurofibrillary tangles. Amyloid plaques are experimentally generated in animal models in order to investigate the disease process. In this study, we followed a rat model of AD for over a year. Wistar rats were divided randomly into two groups as control group (surgery without injection Aß), and experimental group (two­sided intrahippocampal amyloid­beta injection into hippocampus). From each group, three animals were investigated 42 days after injection, and the remaining four animals were studied after one year. All animals were tested for learning abilities and memory. Finally, samples from blood, brain, heart, kidney, liver, colon and spleen were examined. In the experimental group, the size of amyloid plaques were increased significantly after one year \\r\\nand learning abilities and memory were concomitantly decreased. Onsets of various other conditions such as liver and kidney disorders, diabetes, and metabolic syndrome were observed, which indicates that the animals may be prone to cardiovascular disorders and ischemia.

Comparing reactive oxygen species and DNA fragmentation in semen samples of unexplained infertile and healthy fertile men.

BACKGROUND: Male factor infertility has increased to more than 40% during the last decade. About 30% of these couples are diagnosed with unexplained infertility. In fact, reactive oxygen species (ROS), especially superoxide anion (O2-·) and hydrogen peroxide (H2O2), play a crucial role in regulation of physiological and pathological processes in spermatozoa. Moreover, since the diagnosis of unexplained infertility just through semen analysis is a matter of much controversy; we aimed to evaluate the levels of ROS and sperm DNA fragmentation in the semen samples of unexplained infertile and fertile control couples. METHODS: The semen samples of 28 unexplained infertile couples and 30 fertile control couples were analyzed according to WHO criteria. The intracellular levels of H2O2 and O2-· were detected by flow cytometry with 2',7'-Dichlorodihydrofluorescin diacetate and Dihydroethidium, respectively, and DNA fragmentation was evaluated by sperm chromatin dispersion test. RESULTS: In unexplained infertile group, sperm motility and normal morphology were significantly lower than the control. The levels of sperm H2O2, O2-·, and DNA fragmentation were significantly higher in unexplained infertile men compared to fertile. Moreover, a positive correlation was found between the level of H2O2 and sperm DNA fragmentation in the unexplained infertile group. Besides, reduced sperm motility in the unexplained infertile group was significantly correlated with elevated levels of ROS. CONCLUSIONS: The higher levels of intracellular ROS and DNA fragmentation in the semen samples of unexplained infertile couples and their causes might be considered as an important factor related to diagnosis and treatment of the unexplained infertile couples.

Turmeric effect on subcutaneous insulin-induced amyloid mass: an in vivo study.

Protein-derived amyloid structures are associated with a wide variety of pathologies, including neurodegenerative diseases and local amyloidoses. Reports exist on the ability of insulin to form local amyloidoses under specific conditions. In vitro-generated fibrils of insulin have been previously shown to produce amyloid-containing masses upon repetitive subcutaneous injection in mouse. The present study aimed at investigating the effect of insulin fibrils injection in rats, as well as the potential of turmeric in attenuating this process. It was found that subcutaneous amyloid-containing masses could form in rats at a faster rate compared with mice. Upon addition of turmeric to the fibrils, previous to injection, formed masses had a significantly reduced size, as well as less ordered cellular structure. In conclusion, the results of this study show the potential of turmeric in attenuation of local amyloidosis. Furthermore, we suggest that this model could be of use in screening antiamyloid compounds.

Thermal analysis of magnetic nanoparticle in alternating magnetic field on human HCT-116 colon cancer cell line.

PURPOSE: The purpose of this study was to closely investigate the effects of heat dissipation of superparamagnetic nanoparticles on HCT-116 human cancer cell lines cultured under laboratory conditions and also to examine important parameters including size and concentration of nanoparticles, magnetic field frequency, magnetic field intensity, and exposure time. MATERIALS AND METHODS: Conducting experimental tests required special hardware capable of producing an AC magnetic field with various frequencies. The design and construction process for such an experimental set-up is presented here. First, three different Fe3O4 nanoparticle sizes (8, 15 and 20 nm) with different concentrations (d = 10, 20, 40, 80, 160 and 200 µg/ml) were added to cell culture medium and the resulting mixture was exposed to an AC magnetic field with maximum amplitude of 10 kOe for 30 min under three operating frequencies (f = 80, 120 and 180 kHz). The level of intracellular iron was estimated by the ferrozine-based colorimetric assay. Three concentrations including 20, 40 and 80 µg/ml from each of the three nanoparticles sizes were chosen for the study. RESULTS: It was shown that the power dissipation is a function of frequency, time, nanoparticles size and dose. It was also found that the alternating magnetic field with three different frequencies (f = 80, 120 and 180 kHz) and the maximum amplitude of 10 kOe did not have any adverse effect on cell survival. CONCLUSIONS: Our results demonstrate that where thermal dose is equal to 4.5 ± 0.5 °C/30 min from a starting temperature of 37 °C, HCT-116 cell death is initiated when a magnetic nanoparticle electromagnetic field induced.

Systematic review of available guidelines on fertility preservation of young patients with breast cancer.

BACKGROUND: Since the survival rate of breast cancer patients has improved, harmful effects of new treatment modalities on fertility of the young breast cancer patients has become a focus of attention. This study aimed to systematically review and critically appraise all available guidelines for fertility preservation in young breast cancer patients. MATERIALS AND METHODS: Major citation databases were searched for treatment guidelines. Experts from relevant disciplines appraised the available guidelines. The AGREE II Instrument that includes 23 criteria in seven domains (scope and purpose of the guidelines, stakeholder involvement, rigor of development, clarity, applicability, editorial independence, and overall quality) was used to apprise and score the guidelines. RESULTS: The search strategy retrieved 2,606 citations; 72 were considered for full-text screening and seven guidelines were included in the study. There was variability in the scores assigned to different domains among the guidelines. ASCO (2013), with an overall score of 68.0%, had the highest score, and St Gallen, with an overall score of 24.7%, had the lowest scores among the guidelines. CONCLUSIONS: With the promising survival rate among breast cancer patients, more attention should be given to include specific fertility preservation recommendations for young breast cancer patients.

Assessment of α4, αv, ß1 and ß3 integrins expression throughout the implantation window phase in endometrium of a mouse model of polycystic ovarian syndromes.

BACKGROUND: Endometrial integrin expression changes might be a reason for implantation failure in polycystic ovarian syndromes (PCOS). Objective : Assessment of integrin genes and proteins expression upon endometrium in the PCOS experimental mouse model was the main goal of this study. MATERIALS AND METHODS: 30 NMRI female mice were equally divided into control, experimental (PCOS; received estradiol valerate (40 mg/kg)) and sham group (received; olive oil). After 8 weeks, each group was hyper stimulated by 7 IU PMSG and then, after 48hrs, 7 IU HCG was injected. Vaginal plaque was checked. After 5 days, Progesterone and estradiol levels and endometrial tissues were investigated to evaluate of α4, αv, ß1 and ß3 integrins gene and protein by qPCR method and immunohistochemistry, respectively. RESULTS: Tissue samples were assessed and showed that level of progesterone was significantly decreased in PCOS group. RESULTS of molecular part in the amount of αv, ß3, ß1 and α4 gene expressions showed a great difference in ß3 and αv genes expressions between experimental groups. αv, ß3, α4 and ß1 proteins in the endometrial stroma in the control group were expressed, but they were not detected in PCOS group. CONCLUSION: According to the results, integrins had different expression patterns in different areas of the endometrium; such as epithelial and stromal. It seems that in PCOS, this pattern has changed and the results might have a great influence on implantation failure. Therefore, this study suggests that a great attention to this problem may be essential in patients who are involved.

Expression of α4, αv, ß1 and ß3 integrins during the implantation window on blastocyst of a mouse model of polycystic ovarian syndromes.

BACKGROUND: It has been hypothesized that blastocyst integrin expression changes can affect the spontaneous miscarriage in polycystic ovarian syndromes (PCOS). OBJECTIVE: In this study, the profile of integrin genes and proteins was investigated on blastocyst of the PCOS experimental mouse model. MATERIALS AND METHODS: 30 NMRI female mice were equally divided into 3 groups: control, experimental [PCOS that was injected estradiol valerate (40 mg/kg)]. After 8 weeks, each group was hyper stimulated by PMSG and HCG. Vaginal plaque was checked, and mice were investigated 5 days after the test. Progesterone and estradiol levels were determined; α4, αv, ß1 and ß3 integrin genes and protein of blastocysts were examined by real time PCR method and immunohistochemistry, respectively. RESULTS: Estradiol level was significantly increased (p≤0.035) in PCOS group. Based on our finding, the ratio of genes' expressions αv, ß3, ß1 and α4 in PCOS to control group was 0.479±0.01, 0.5±0.001, 2.7±0.4 and 1.023±0.2 respectively. Genes expression showed a great difference (p≤0.001) between ß3, ß1 and αv in PCOS compared to other groups. αv and ß3 integrin proteins expressed in all groups but intensity of these proteins in PCOS groups, was lower than other groups. CONCLUSION: Pattern of αv and ß3 integrins expression on the mouse blastocyst surface has an important effect during the implantation window. This pattern has changed in PCOS model and might have a great influence on implantation failure. Therefore, this experimental study suggests that a great attention to this problem may be essential in patients who are involved.

FGF10: Type III Epithelial Mesenchymal Transition and Invasion in Breast Cancer Cell Lines.

PURPOSE: Fibroblastic growth factor-10 (FGF-10) has an important role in type I epithelial mesenchymal transition (EMT) during the embryonic period of life (gastrulation). Since EMT has a critical role during cancer cells invasion and metastasis (type III) this study sought to investigate the possible role of FGF-10 in type III EMT by monitoring breast cancer cell lines' behavior by FGF-10 regulation. METHODS: MCF-7 and MDA-MB-231 cell lines with different levels of FGF10 expression were treated with FGF-10 recombinant protein and FGF-10 siRNA, respectively. RESULTS: The cell viability, migration, colony formation and wound healing have a direct relationship with FGF-10 expression, while FGF-10 expression decreased apoptosis. All mesenchymal factors (such as vimentin, N cadherin, snail, slug, TGF-ß) increased due to FGF-10 expression with contrary expression of epithelial markers (such as E-cadherin). Moreover, GSK3ß phosphorylation (inactivation) increased with FGF-10 expression. CONCLUSION: The important role of FGF-10 in type III EMT on cancer cells and initiation of metastasis via various kinds of signaling pathways has been suggested.

HeLa cell line xenograft tumor as a suitable cervical cancer model: growth kinetic characterization and immunohistochemistry array.

BACKGROUND: Cervical cancer is the seventh most common malignancy in both genders combined and the third most common cancer in women. Despite significant progress in treatments, cervical cancer is not completely curable. Therefore, further research is necessary in this area. Animal models are one of the most practical tools in the field of cancer research. The present study aimed to characterize the growth behavior and surface markers of HeLa cells after heterotopic and systemic inoculation to athymic nude mice. METHODS: Ten 6-week old female athymic C57BL/6 nude mice were used in this study. HeLa cells were inoculated into the flank or tail vein. The tumor volume was calculated and growth curves were drawn. Tumor-bearing mice were sacrificed and the lesions obtained after harvesting were analyzed in a pathology lab. Subsequently, one slide per tumor was stained with hematoxylin and eosin (H&E) and other slides were stained immunohistochemically by cytokeratins (CK), vimentin, P53, CD34, and Ki-67. RESULTS: Tumor take rate, mean doubling time and latency period were 94.4%, 5.29 ± 3.57 days and 15.27 days, respectively. H&E results revealed highly malignant hyperchromatin epithelial cells. Immunohistochemical examination of the heterotopic tumors indicated greater expression of CK and less expression of vimentin compared to the metastatic ones. Sixty percent of cells were P53-positive and more than 80% were Ki-67-positive. CD34 expression indicated the intensity of angiogenesis in tumor. CONCLUSION: This study represents a comprehensive description of a HeLa xenograft model for in vivo investigations, enabling researchers to assess new treatments for cervical cancer.

In vitro assessment of antineoplastic effects of deuterium depleted water.

BACKGROUND: In vitro, in vivo and clinical studies have demonstrated anti-cancer effects of deuterium depleted water (DDW). The nature of this agents action, cytotoxic or cytostatic, remains to be elucidated. We here aimed to address the point by examining effects on different cell lines. MATERIALS AND METHODS: 3-(4, 5-dimethylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) -based cytotoxicity analysis was conducted for human breast, stomach, colon, prostate cancer and glioblastoma multiforme cell lines as well as human dermal fibroblasts. The cell lines were treated with decreasing deuterium concentrations of DDW alone, paclitaxel alone and both. One way analysis of variance (ANOVA) was used for statistical analysis. RESULTS: Treatment with different deuterium concentrations of DDW alone did not impose any significant inhibitory effects on growth of cell lines. Paclitaxel significantly decreased the survival fractions of all cell lines. DDW augmented paclitaxel inhibitory effects on breast, prostate, stomach cancer and glioblastoma cell lines, with influence being more pronounced in breast and prostate cases. CONCLUSIONS: DDW per se does not appear to have inhibitory effects on the assessed tumor cell lines as well as normal fibroblasts. As an adjuvant, however, DDW augmented inhibitory effects of paclitaxel and thus it could be considered as an adjuvant to conventional anticancer agents in future trials.

Establishment of a patient-derived Wilms' tumor xenograft model: a promising tool for individualized cancer therapy.

OBJECTIVE: Lack of appropriate approaches that reliably predict response of Wilms' tumor (WT) to anticancer agents remains a major deficiency in clinical practice of individualized cancer therapy. The aim of this study was to establish a patient-derived tumor tissue (PDTT) xenograft model of WT for individualized chemotherapeutic regimen selection in accordance with the patient's tumor nature. MATERIAL AND METHODS: Tumor specimens of a primary WT were orthotopically implanted into three nude mice, and after 4 weeks xenografts were harvested for serial heterotopic transplantation in 20 nude mice that were divided into three experimental groups and one control group. In vitro and in vivo chemosensitivity to doxorubicin, actinomycin-D, and vincristine were evaluated. Hematoxylin and eosin (H&E) staining and immunohistochemical examination with desmin, vimentin, myogenin, and neuron-specific enolase (NSE) were also applied to determine histological stability of the xenograft during serial transplantation compared with the original tumor tissue. RESULTS: The xenograft model was successfully established. Histopathologic characteristics of the xenograft tumors were similar to the patient's tumor. Early passage of the PDTT showed a similar chemosensitivity pattern to the original tumor tissue. CONCLUSIONS: PDTT xenograft of WT provides an appropriate model for individualized cancer therapeutic regimen selection by means of its biological stability compared with original patient's tumor.

Feasibility assessment of in vitro chemoresponse assay on stereotactic biopsies of glioblastoma multiforms: a step towards personalized medicine.

OBJECTIVES: P In vitro chemosensitivity and resistance assays (CSRAs) are a promising tool for personalized treatment of glioblastoma multiform (GBM). These assays require a minimum of 1 to 2 g of tumor specimen for testing, but this amount is not always accessible. We aimed to assess the feasibility and validity of utilizing stereotactic biopsies of GBM in CSRAs. MATERIALS AND METHODS: Single cell suspension was prepared from 1 g weight explants of the established xenograft tumor of GBM. Also, primary culture was carried out on 35 mg weight specimens, as a surrogate for stereotactic biopsies. Then, chemoresponse profile of cells obtained by direct cell disaggregation and primary culture was determined using temozolomide and carmustine by clonogenic assay. RESULTS: There was no statistically significant difference in the cytotoxicity of temozolomide and carmustine between cells obtained from both methods. CONCLUSION: This work supports the feasibility of using stereotactic biopsies of GBM in CSRAs.

Caspase-mediated apoptosis in sensory neurons of cultured dorsal root Ganglia in adult mouse.

OBJECTIVE: Sensory neurons in dorsal root ganglia (DRG) undergo apoptosis after peripheral nerve injury. The aim of this study was to investigate sensory neuron death and the mechanism involved in the death of these neurons in cultured DRG. MATERIALS AND METHODS: In this experimental study, L5 DRG from adult mouse were dissected and incubated in culture medium for 24, 48, 72 and 96 hours. Freshly dissected and cultured DRG were then fixed and sectioned using a cryostat. Morphological and biochemical features of apoptosis were investigated using fluorescent staining (Propidium iodide and Hoechst 33342) and the terminal Deoxynucleotide transferase dUTP nick end labeling (TUNEL) method respectively. To study the role of caspases, general caspase inhibitor (Z-VAD.fmk, 100 µM) and immunohistochemistry for activated caspase-3 were used. RESULTS: After 24, 48, 72 and 96 hours in culture, sensory neurons not only displayed morphological features of apoptosis but also they appeared TUNEL positive. The application of Z-VAD.fmk inhibited apoptosis in these neurons over the same time period. In addition, intense activated caspase-3 immunoreactivity was found both in the cytoplasm and the nuclei of these neurons after 24 and 48 hours. CONCLUSION: Results of the present study show caspase-dependent apoptosis in the sensory neurons of cultured DRG from adult mouse.

Correlation of microvessel density with nuclear pleomorphism, mitotic count and vascular invasion in breast and prostate cancers at preclinical and clinical levels.

BACKGROUND: Tumor angiogenesis correlates with recurrence and appears to be a prognostic factor for both breast and prostate cancers. In the present study, we aimed to investigate the correlation of microvessel density (MVD), a measure of angiogenesis, with nuclear pleomorphism, mitotic count, and vascular invasion in breast and prostate cancers at preclinical and clinical levels. METHODS: Samples from xenograft tumors of luminal B breast cancer and prostate adenocarcinoma, established by BT-474 and PC-3 cell lines, respectively, and commensurate human paraffin-embedded blocks were obtained. To determine MVD, specimens were immunostained for CD-34. Nuclear pleomorphism, mitotic count, and vascular invasion were determined using hematoxylin and eosin (HandE)-stained slides. RESULTS: MVD showed significant correlations with nuclear pleomorphism (r=0.68, P=0.03) and vascular invasion (r=0.77, P=0.009) in breast cancer. In prostate cancer, MVD was significantly correlated with nuclear pleomorphism (r=0.75, P=0.013) and mitotic count (r=0.75, P=0.012). In the breast cancer xenograft model, a significant correlation was observed between MVD and vascular invasion (r=0.87, P=0.011). In the prostate cancer xenograft model, MVD was significantly correlated with all three parameters (nuclear pleomorphism, r=0.95, P=0.001; mitotic count, r=0.91, P=0.001; and vascular invasion, r=0.79, P=0.017; respectively). CONCLUSIONS: Our results demonstrate that MVD is correlated with nuclear pleomorphism, mitotic count, and vascular invasion at both preclinical and clinical levels. This study therefore supports the predictive value of MVD in breast and prostate cancers.