Impact of underlying stress in infertility.

PURPOSE OF REVIEW: To review the latest findings about the impact of women's physiological stress on fertility treatment outcomes and the main biomarkers used. RECENT FINDINGS: Women with infertility report high levels of distress that can impact their treatment outcome. The combination of multiple methodologies in psychological stress evaluation result in higher validity, precision and richness in the data. Hair cortisol levels seem to be a promising biomarker to be associated to treatment outcomes. SUMMARY: The impact of distress on treatment outcome can be assessed with the help of biomarkers. Decreasing burden of treatment may lead to relevant improvements in assisted reproductive technology outcome.

Type of gonadotropin used during controlled ovarian stimulation induces differential gene expression in human cumulus cells: A randomized study.

BACKGROUND: The cumulus-oocyte complex plays a central role in the regulation of folliculogenesis where it is important for the maturation, reprogramming, and fertilization of oocytes. Consequently, cumulus cell gene expression profiling is being explored as a promising method for assessing oocyte competence in the near future. Through DNA microarray technology, we analyzed the potential differences in the gene expression profiles of cumulus cells from preovulatory follicles after controlled ovarian stimulation using different types of gonadotropins. METHODS: A prospective, randomized study was performed among 90 women participating in an oocyte donation program. Subjects were assigned to receive recombinant follicle-stimulating hormone (FSH), urinary FSH, or human menopausal gonadotropin (hMG). The gene expression profile in cumulus cells was analyzed according the type of gonadotropin received during ovarian stimulation. Furthermore, we also performed a gene ontology analysis to provide structural knowledge. RESULTS: Hierarchical clustering, principal component analysis, and gene enrichment analysis revealed greater differences between the urinary FSH and hMG groups compared to the rest of the pair-wise comparisons; recombinant FSH vs hMG and urinary FSH vs recombinant FSH. CONCLUSIONS: Data suggest that controlled ovarian stimulation induces specific gene expression profiles in human cumulus cells depending on the type of gonadotropin used. TRIAL REGISTRATION: Registered at clinicaltrials.gov; identifier NCT022437032.

Should we forget about embryos till day 5?

PURPOSE OF REVIEW: To find the way of having more and better blastocyst is essential. How to culture embryos up to blastocyst stage remains critical. RECENT FINDINGS: Several studies show how a blastocyst score can predict the implantation potential. If that score is enough to choose the best blastocyst, as culture conditions would not be affected in these days, we would not need to check early cleavage embryos, even it could be better for the embryo development. SUMMARY: The item that should be discussed is if it is better to evaluate or not embryos at early cleavage stages. If we do not check embryos on days 2 and 3, we should change our way to work and how to culture those embryos. First step would be to perform all embryo transfers on day 5 or 6. If we let embryos grow to blastocyst without any morphology evaluation, we should adapt several steps in our laboratory, for example we should move to a single-step culture medium or we should not do assisted hatching on day 3 embryos.

Type of gonadotropin during controlled ovarian stimulation affects the endocrine profile in follicular fluid and apoptosis rate in cumulus cells.

OBJECTIVE: To determine whether the type of gonadotropin affects the secretion of oocyte-specific factors, the endocrine pattern in follicular fluid, and the apoptosis rate in cumulus cells. STUDY DESIGN: Prospective and observational study into an university-affiliated private in vitro fertilization setting. Ninety women included in our oocyte donation program were stimulated with human menopausal gonadotropin (hMG), recombinant follicle-stimulating hormone (FSH) or urinary FSH. Main outcome measures were growth-differentiation factor 9 (GDF-9) and bone morphogenetic protein 15 (BMP-15) expression, hormonal profile and apoptosis rate. RESULTS: No statistically significant differences were observed for GDF-9 and BMP-15 among the three treatment groups. Estradiol concentrations in follicular fluid were significantly higher in women treated with hMG compared with recombinant FSH or urinary FSH. Testosterone levels were also higher in the group treated with hMG. A statistically significant association was found between the degree of apoptosis in cumulus cells and the type of gonadotropin. CONCLUSIONS: The type of gonadotropin used during controlled ovarian stimulation significantly affects endocrine profiles in follicular fluid and the apoptosis rate in cumulus cells. However, there were no significant differences in the levels of oocyte-secreted factors between treatments.

FSH receptor in vitro modulation by testosterone and hCG in human luteinized granulosa cells.

OBJECTIVE: To investigate the effect of testosterone and hCG on FSH receptor (FSHR) protein and mRNA expression in human granulosa cells (GC) in vitro. STUDY DESIGN: Experimental in vitro cell culture obtained from healthy women undergoing IVF/ICSI due to male factor infertility. Human follicular fluid samples were obtained and after cumulus-oocyte complexes were identified, fluids were pipetted onto Ficoll gradients and centrifuged for 15 min at 400 × g at room temperature. Cells at the interface were removed and plated in 24-well plates for 3 days in M-199 with 10% FBS. Cells were treated with different concentrations of testosterone and hCG. After purification, cells were labeled with specific antibodies and the protein expression of the FSHR was evaluated by flow cytometry in the GC population. Also, total RNA was extracted from confluent GC and the FSHR gene expression was evaluated by RT-PCR. RESULTS: FSHR expression was modulated by treating GC in vitro at different testosterone/hCG concentrations. When compared with untreated GC, we observed a significant effect of testosterone and hCG on the expression of the FSHR at the protein level. Time course experiments confirmed that the gene expression of the FSHR peaked at 12-24h when testosterone or hCG was used as a stimulus. CONCLUSIONS: Both testosterone and hCG are able to positively modulate FSHR expression at gene and protein level in human GC in vitro.

The impact of in-vitro maturation of oocytes on aneuploidy rate.

Chromosome abnormalities in embryos obtained through in-vitro maturation (IVM) of oocytes from 11 oocyte donors were compared with embryos from women undergoing fluorescence in-situ hybridization (FISH) analysis for sex selection. Thirty-three oocytes had reached metaphase II stage at 28-30 h (65%) and 27 were successfully fertilized by intracytoplasmic sperm injection. Blastomere biopsy was performed in 20 embryos (74%). For five embryos, two blastomeres were analysed, three of which were mosaic. FISH study revealed aneuploidies of chromosomes 13, 15, 16, 18, 21, 22, X and Y in 12 embryos (60%) and euploidy in the remaining eight (40%). The percentage of aneuploidies in the control group was 33%. Differences between IVM and control embryos were not statistically significant. The high incidence of chromosome abnormalities in embryos resulting from the IVM protocol may account for the low implantation rates reported by others. Although a greater incidence of miscarriage or congenital abnormalities in babies born alive following IVM versus conventional IVF has not been observed in previous studies, preimplantation genetic aneuploidy screening or prenatal chromosome studies may be recommended to these patients on the basis of the present results.

Positive correlation between the expression of X-chromosome RBM genes (RBMX, RBM3, RBM10) and the proapoptotic Bax gene in human breast cancer.

In a recent report, it has been postulated that the ubiquitous RBM proteins might constitute a novel family of apoptosis modulators. We measured the expression of the X-chromosome RBM genes (RBMX, RBM3, and RBM10) in 122 breast cancers by means of differential RT-PCR. Using the same method, we also studied the expression of the apoptosis-related genes Bcl-2 and Bax. Markers of hormone dependence (estrogen and progesterone receptors), proliferation (Ki67 and DNA-ploidy), angiogenesis (VEGF and CD105), as well as oncogene (c-erb-B2), and tumor suppressor gene (p53) expression were also analyzed. The expression of all X-chromosome RBM genes was significantly associated with the expression of the proapoptotic Bax gene (RBMX, P=0.039; RBM3, P<0.001; RBM10 large variant, P<0.001; RBM10 small variant, P<0.001). Furthermore, the expression of both RBM10 variants was significantly associated with the expression of the VEGF gene (large variant, P=0.004; small variant, P=0.003). We also found an association of borderline significance (P=0.05) between the expression of RBM3, the large variant of RBM10 and wild-type p53. Expression of the small RBM10 variant, finally, was associated with high proliferation of the tumors (Ki67>or=20%; P=0.037). The expression of both RBM10 variants seems to be interdependent to a significant degree (r=0.26, P=0.006). From these results, it seems that the X-chromosome, through its RBM genes, plays a formerly unknown role in the regulation of programmed cell death (apoptosis) in breast cancer.

Characterization of a human Bid homologue protein from Gallus gallus.

Bid protein, a member of the "BH3-only" subgroup of Bcl-2 family, plays a critical role in mammalian apoptosis regulation. In this study, we have cloned the chicken Bid gene, which encodes a 193 amino acid protein and shares 40% homology with human and mouse Bid proteins. Bid sequence comparison emphasises the conservation of both the functional domain BH3 and the proteolytic cleavage sites. An induction of apoptosis by chicken Bid and the cleavage of the protein, after TNFalpha treatment, were also demonstrated. In addition, mRNA Bid expression was detected along all embryo stages and tissues examined, suggesting a role for this protein in the developmental process. This is the first report demonstrating the functionality of a "BH3-only" protein in chicken.

Proteomic analysis of the Gallus gallus embryo at stage-29 of development.

The chicken (Gallus gallus) is one of the primary models for embryological and developmental studies. In order to begin to understand the molecular mechanisms underlying the normal and abnormal development of the chicken, we used 2-DE to construct a whole-embryo proteome map. Proteins were separated by IEF on IPG strips, and by 11% SDS-PAGE) gels. Protein identification was performed by means of PMF with MALDI-TOF-MS. In all, 105 protein spots were identified, 35 of them implicated in embryo development, 10 related with some diseases, and 16, finally, being proteins that have never been identified, purified or characterized in the chicken before. This map will be updated continuously and will serve as a reference database for investigators, studying changes at the protein level under different physiological conditions.

mRNA expression of the angiogenesis markers VEGF and CD105 (endoglin) in human breast cancer.

BACKGROUND: Both VEGF and CD105 (endoglin) have been identified as markers of tumor angiogenesis and prognosis in breast cancer. They have always been studied in this kind of tumor by means of immunological methods. OBJECTIVE: To study, by means of reverse-transcription polymerase chain reaction (RT-PCR), the expression of VEGF and CD105 (endoglin) at the mRNA level in a series of breast cancers and to correlate the results obtained with all available clinical and biological features of the tumors. MATERIALS AND METHODS: Fresh tumor tissue from 103 previously untreated breast cancer patients was studied for VEGF and CD105 (endoglin) expression. In addition, the following parameters were determined in all tumors: DNA ploidy by means of flow cytometry; hormone receptor (ER & PR), Ki67, c-erb-B2 and p53 expression by means of immunohistochemistry; and h-MAM (mammaglobin) expression by means of RT-PCR. Classical prognostic parameters of the tumors, such as histological and nuclear grade or axillary lymph node invasion, were also included into the statistical analysis. RESULTS: VEGF mRNA expression levels above the 25th percentile were significantly (p<0.05) associated with high proliferation (Ki67>10%) and aneuploidy of the tumors and inversely with estrogen receptor expression (p<0.01). CD105 (endoglin) mRNA expression levels above the 25th percentile only correlated significantly with nuclear grade 3 (p<0.05). The expression of both genes did not correlate with each other. CONCLUSION: VEGF mRNA expression levels seem to be directly associated with VEGF functions at the protein level, whereas this seems not to be the case for CD105 (endoglin) mRNA levels.

Nup88 mRNA overexpression is associated with high aggressiveness of breast cancer.

The nuclear pore complex protein Nup88 is overexpressed in tumor cells. Immunohistochemical studies have shown that this overexpression is linked to higher aggressiveness of colorectal carcinoma and to enhanced metastatic potential of melanoma cells. However, the antibodies so far developed against Nup88 have the drawback of recognizing a number of other, up to now unspecified antigens besides Nup88. For this reason, we devised the present study on Nup88 expression at the mRNA level. RNA was extracted from fresh tumor tissue corresponding to 122 breast cancer patients. Nup88 mRNA expression was measured by means of differential RT-PCR, standardizing against a constitutive internal control gene (beta-actin). The results were dichotomized into "high" and "low" expression levels, using the median value as cut-off. High Nup88 mRNA expression levels correlated significantly with ductal and tubular histology (p = 0.012), histologic and nuclear grade 3 of tumors (p < 0.001), absence of hormone receptor expression (p < 0.001), expression of the c-erb-B2 oncogene (p < 0.001), expression of mutant p53 protein (p < 0.001), high proliferation (defined by Ki67 labeling index >20%, p < 0.001), DNA aneuploidy (p < 0.001) as well as the most important ominous clinical prognostic factor, axillary node invasion (p < 0.001). We also found an inverse correlation (p < 0.001) with expression of the H-MAM (mammaglobin) gene, a marker of low biologic and clinical aggressiveness of breast cancer. All of these factors, without exception, define a highly aggressive tumor phenotype. These findings appear to be specific to Nup88 and not to nuclear pore proteins in general. Indeed, analysis of Nup107 (which is a limiting component of the nuclear pore complex) under the same conditions in the same tumors did not yield comparable results.

A proteomic approach to study Salmonella typhi periplasmic proteins altered by a lack of the DsbA thiol: disulfide isomerase.

Two-dimensional electrophoresis (2-DE) was used to analyze the pleiotropic effects of a deficiency in DsbA, a periplasmic disulfide-bond oxidoreductase, in Salmonella typhi. With this aim, the dsbA gene was cloned and assayed for activity in a dsbA-null mutant of Escherichia coli. A dsbA/chloramphenicol acetylase construct was then used to disrupt the wild-type gene of S. typhi. The resultant dsbA-null mutant of S. typhi, like the E. coli mutant, exhibited a lack of flagellation and of glucose-1-phosphatase activity. Periplasmic extracts from the parental and mutant strains were analyzed by 2-DE using standard denaturing and nondenaturing conditions. Differences in protein expression were more marked in nondenaturing conditions. Ninety-nine protein spots were analyzed by peptide mass fingerprinting, and 65 spots were identified by searching a S. typhi database. Twenty-five spots were exclusively detected in the wild-type strain, 10 were found only in the mutant strain, and 21 were common to both strains. We observed a lack of DsbA, glucose-1-phosphatase and flagellin in the dsbA-null mutant, which explains two of the observed phenotypes. The AI-2 autoinducer-producing protein LuxS, which is involved in quorum-sensing signalling was also absent.