Faculty Bibliography

Objective: Clinical guidelines on the optimal duration of controlled ovarian stimulation and ideal follicle size were developed for fresh embryo transfer cycles. Whether these apply to freeze all cycles remain unclear. We evaluated the impact of lead follicle size and duration of stimulation on the probability of euploid embryos in women undergoing IVF/PGT-A Design: Cross-sectional study
Material(s) and Method(s): Data from 721 patients undergoing at least two cycles of COS for IVF with preimplantation genetic testing for aneuploidy (PGT-A) via Next Generation Sequencing (NGS) (1859 cycles). Mixed-effect logistic regression, which can account for correlations among repeated outcomes within sample patients, was used to evaluate the association between independent variables and probability of achieving euploid embryos. We first conducted a mixed-effect logistic regression in a univariate manner. All variables then were evaluated in a multivariate model to control for confounding effects. Significant variables to p<0.05 were retained in the final model. p-values <0.05 were considered significant. Statistical analyses were performed using "nlme" and "lme4" package from R project. Results are reported as odds ratios (OR) with 95% confidence intervals (CI).
Result(s): Increasing sum (1.034 [1.022 1.046]/p<0.001) and mean diameter (1.129 [1.046 1.219] p=0.002) of the 5 largest follicles increased the probability of forming euploid embryos. Increasing days of stimulation showed a non-significant trend toward lower chance of forming euploid embryos (0.976 [0.923 1.031]/p=0.382) (Table 1).
Conclusion(s): Allowing the lead follicles to exceed 18mm increases the total number of euploid embryos formed per cycle, presumably by enabling retrieval of additional mature oocytes. Evidence of a detrimental effect of excessive follicle size was not evident in our study, though the number of cycles with follicles exceeding 24 mm was limited. The non-significant trend toward decreased euploid embryos following prolonged stimulation may reflect the effects of poor responders. [Figure presented]
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Objective: Treatment of chronic endometritis (CE) improves implantation rates in patients undergoing assisted reproductive technology (ART), but causative organisms are difficult to identify and the most effective treatment regimen remains undefined¹. Our objective was to identify the optimal duration and choice of antimicrobial agent(s) on clearance of CE.
Design(s): Retrospective cohort study of patients between 1/2017 and 12/2018 at a single academic center with an endometrial biopsy (EMB) showing CE.
Material(s) and Method(s): All patients diagnosed with CE (defined as >1 plasma cell/HPF, stained for CD138) on EMB followed by test of cure biopsy (TOC) were included. Antimicrobial agents prescribed and length of course were recorded. Regimens were classified as 14 days or less versus 15 days or more (up to 21 days), and by spectra of coverage: Gram positive, Gram negative, Anaerobe, Atypical and Anti-fungal. Primary outcome was presence or absence of CE on TOC. If a patient remained positive on TOC, subsequent treatment(s) were included as separate course(s) for analysis. Statistical analysis included chi square test of independence and a stepwise multiple logistic regression, with p < 0.05 significant.
Result(s): 144 women with an initial EMB positive for CE received a total of 225 treatment courses. 11 TOC results were unavailable, leaving 214 courses of treatment with known TOC outcomes. The most common indication for EMB was failed frozen embryo transfer(s) (FET) (mean 0.98+/-1.00, range 0-7), euploid pregnancy loss or recurrent pregnancy loss. The mean age of women in the cohort was 36.90+/-3.93 years (range 27-47). Mean number of courses required for clearance was 1.55+/-0.88 (range 0-6). All courses included antimicrobials providing gram positive and negative coverage. 62.6% (134/214) included anaerobic coverage and 66.3% (142/214) included atypical agent(s). 2 courses included anti-fungals. Including anaerobic coverage did not affect outcome (58.2% with vs 61.3% without, p = 0.67), nor did use of an atypical agent (59.2% with vs 59.67% without, p=1.00). Antibiotic regimens lasting 14 days or less (n=155) had lower rates of CE clearance when compared to those lasting 15 days or more (54.8% vs 71.2%, p < 0.03). Stepwise multiple logistic regression showed that only length of antimicrobial course retained a significant impact on TOC (B -0.762, p < 0.027, Omnibus test for variance p <0.024, Hosmer-Lemeshow test for fit p = 0.99).
Conclusion(s): CE is a treatable but poorly defined inflammatory process, which may affect ART success. Ideally, CE is cleared with the first course of antibiotics. Our results show that longer courses (15-21 days) are more effective, regardless of antimicrobial choice. This suggests that patients do not need to take less tolerable agents to achieve high clearance rates, and highlights the need for further, prospective analyses. References: ¹: Cicinelli E, et al. Prevalence of chronic endometritis in repeated unexplained implantation failure and the IVF success rate after antibiotic therapy. Human Reproduction 2015;30(2):323-330.
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Cell fate transitions are accompanied by global transcriptional, epigenetic and topological changes driven by transcription factors, as is exemplified by reprogramming somatic cells to pluripotent stem cells through the expression of OCT4, KLF4, SOX2 and cMYC. How transcription factors orchestrate the complex molecular changes around their target gene loci remains incompletely understood. Here, using KLF4 as a paradigm, we provide a transcription-factor-centric view of chromatin reorganization and its association with three-dimensional enhancer rewiring and transcriptional changes during the reprogramming of mouse embryonic fibroblasts to pluripotent stem cells. Inducible depletion of KLF factors in PSCs caused a genome-wide decrease in enhancer connectivity, whereas disruption of individual KLF4 binding sites within pluripotent-stem-cell-specific enhancers was sufficient to impair enhancer-promoter contacts and reduce the expression of associated genes. Our study provides an integrative view of the complex activities of a lineage-specifying transcription factor and offers novel insights into the nature of the molecular events that follow transcription factor binding.

Repair of DNA damage protects genomic integrity, which is key to tissue functional integrity. In cancer, the type and fidelity of DNA damage response is the fundamental basis for clinical response to cytotoxic therapy. Here we consider the contribution of transforming growth factor-beta (TGFβ), a ubiquitous, pleotropic cytokine that is abundant in the tumor microenvironment, to therapeutic response. The action of TGFβ is best illustrated in head and neck squamous cell carcinoma (HNSCC). Survival of HNSCC patients with human papilloma virus (HPV) positive cancer is more than double compared to those with HPV-negative HNSCC. Notably, HPV infection profoundly impairs TGFβ signaling. HPV blockade of TGFβ signaling, or pharmaceutical TGFβ inhibition that phenocopies HPV infection, shifts cancer cells from error-free homologous-recombination DNA double-strand-break (DSB) repair to error-prone alternative end-joining (altEJ). Cells using altEJ are more sensitive to standard of care radiotherapy and cisplatin, and are sensitized to PARP inhibitors. Hence, HPV-positive HNSCC is an experiment of nature that provides a strong rationale for the use of TGFβ inhibitors for optimal therapeutic combinations that improve patient outcome.

With more women than ever waiting until a more advanced age to have children, there exists a newfound urgency to identify the various implications aging has on human reproduction, and understand the disrupted biological processes that result in these changes. In this review, we focus on one recent area of study: the age related epigenetic changes that have been found in female reproductive organs, and the effect these changes may contribute to reproductive outcomes.

Cellular senescence is a mechanism used by mitotic cells to prevent uncontrolled cell division. As senescent cells persist in tissues, they cause local inflammation and are harmful to surrounding cells, contributing to aging. Generally, neurodegenerative diseases, such as Parkinson's, are disorders of aging. The contribution of cellular senescence to neurodegeneration is still unclear. SATB1 is a DNA binding protein associated with Parkinson's disease. We report that SATB1 prevents cellular senescence in post-mitotic dopaminergic neurons. Loss of SATB1 causes activation of a cellular senescence transcriptional program in dopamine neurons both in human stem cell-derived dopaminergic neurons and in mice. We observed phenotypes that are central to cellular senescence in SATB1 knockout dopamine neurons in vitro and in vivo. Moreover, we found that SATB1 directly represses expression of the pro-senescence factor p21 in dopaminergic neurons. Our data implicate senescence of dopamine neurons as a contributing factor in the pathology of Parkinson's disease.

Drug Affinity Responsive Target Stability (DARTS) is a robust method for detection of novel small molecule protein targets. It can be used to verify known small molecule-protein interactions and to find potential protein targets for natural products. Compared with other methods, DARTS uses native, unmodified, small molecules and is simple and easy to operate. In this study, we further enhanced the data analysis capabilities of the DARTS experiment by monitoring the changes in protein stability and estimating the affinity of protein-ligand interactions. The protein-ligand interactions can be plotted into two curves: a proteolytic curve and a dose-dependence curve. We have used the mTOR-rapamycin interaction as an exemplary case for establishment of our protocol. From the proteolytic curve we saw that the proteolysis of mTOR by pronase was inhibited by the presence of rapamycin. The dose-dependency curve allowed us to estimate the binding affinity of rapamycin and mTOR. This method is likely to be a powerful and simple method for accurately identifying novel target proteins and for the optimization of drug target engagement.

Dysregulation of the seven-transmembrane (7TM) receptor Smoothened (SMO) and other components of the Hedgehog (Hh) signaling pathway contributes to the development of cancers including basal cell carcinoma (BCC) and medulloblastoma (MB). However, SMO-specific antagonists produced mixed results in clinical trials, marked by limited efficacy and high rate of acquired resistance in tumors. Here we discovered that Nilotinib, an approved inhibitor of several kinases, possesses an anti-Hh activity, at clinically achievable concentrations, due to direct binding to SMO and inhibition of SMO signaling. Nilotinib was more efficacious than the SMO-specific antagonist Vismodegib in inhibiting growth of two Hh-dependent MB cell lines. It also reduced tumor growth in subcutaneous MB mouse xenograft model. These results indicate that in addition to its known activity against several tyrosine-kinase-mediated proliferative pathways, Nilotinib is a direct inhibitor of the Hh pathway. The newly discovered extension of Nilotinib's target profile holds promise for the treatment of Hh-dependent cancers.