Publications by authors named "Beatrice Babbs"

Epithelial ovarian cancers that are nonhomologous recombination deficient, as well as those that are recurrent and in a platinum-resistant state, have limited therapeutic options. The objectives of this study were to characterize the mechanism of action and investigate the therapeutic potential of a small molecule, VDX-111, against ovarian cancer. We examined the ability of VDX-111 to inhibit the growth of a panel of ovarian cancer cell lines, focusing on BRCA wild-type lines.

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The pathogenesis of the marked pulmonary microvasculature injury, a distinguishing feature of COVID-19 acute respiratory distress syndrome (COVID-ARDS), remains unclear. Implicated in the pathophysiology of diverse diseases characterized by endothelial damage, including ARDS and ischemic cardiovascular disease, ceramide and in particular palmitoyl ceramide (C16:0-ceramide) may be involved in the microvascular injury in COVID-19. Using deidentified plasma and lung samples from COVID-19 patients, ceramide profiling by mass spectrometry was performed.

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Ovarian cancer metastasizes via direct seeding, whereby cancer cells shed from the primary site, resist cell death in the peritoneal cavity, then metastasize to peritoneal organs. We sought to identify molecular mechanisms that facilitate ovarian cancer cell anchorage independent survival. Gene expression profiling was performed on ovarian cancer cells grown in attached or forced suspension culture and confirmed by RT-qPCR.

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Preclinical and early clinical trials indicate that up to 50% of triple-negative breast cancers (TNBC) express androgen receptor (AR) and are potentially responsive to antiandrogens. However, the function of AR in TNBC and the mechanisms by which AR-targeted therapy reduces tumor burden are largely unknown. We hypothesized that AR maintains a cancer stem cell (CSC)-like tumor-initiating population and serves as an antiapoptotic factor, facilitating anchorage independence and metastasis.

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The androgen receptor (AR) is widely expressed in breast cancer, and evidence suggests dependence on AR signaling for growth and survival. AR antagonists such as enzalutamide and seviteronel have shown success in preclinical models and clinical trials of prostate cancer and are currently being evaluated in breast cancer. Reciprocal regulation between AR and the HER2/PI3K/mTOR pathway may contribute to resistance to HER2- and mTOR-targeted therapies; thus, dual inhibition of these pathways may synergistically inhibit breast cancer growth.

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Profiling of RNA from mouse mammary epithelial cells (MECs) isolated on pregnancy day (P)14 and lactation day (L)2 revealed that the majority of differentially expressed microRNA declined precipitously between late pregnancy and lactation. The decline in miR-150, which exhibited the greatest fold-decrease, was verified quantitatively and qualitatively. To test the hypothesis that the decline in miR-150 is crucial for lactation, MEC-specific constitutive miR-150 was achieved by crossing ROSA26-lox-STOP-lox-miR-150 mice with WAP-driven Cre recombinase mice.

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Unlabelled: Androgen receptor (AR) is expressed in 90% of estrogen receptor alpha-positive (ER) breast tumors, but its role in tumor growth and progression remains controversial. Use of two anti-androgens that inhibit AR nuclear localization, enzalutamide and MJC13, revealed that AR is required for maximum ER genomic binding. Here, a novel global examination of AR chromatin binding found that estradiol induced AR binding at unique sites compared with dihydrotestosterone (DHT).

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Triple-negative breast cancer (TNBC) has the lowest 5-year survival rate of invasive breast carcinomas, and currently there are no approved targeted therapies for this aggressive form of the disease. The androgen receptor (AR) is expressed in up to one third of TNBC and we find that all AR(+) TNBC primary tumors tested display nuclear localization of AR, indicative of transcriptionally active receptors. While AR is most abundant in the "luminal AR (LAR)" molecular subtype of TNBC, here, for the first time, we use both the new-generation anti-androgen enzalutamide and AR knockdown to demonstrate that the other non-LAR molecular subtypes of TNBC are critically dependent on AR protein.

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Objective: To better understand the site and mode of action of aromatase inhibitors.

Design: Prospective study.

Setting: Academic research environment.

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Microbial biodiversity provides an increasingly important source of medically and industrially useful compounds. We have isolated 14 actinomycete species from a collection of approximately 300 plant stem samples from the upper Amazonian rainforest in Peru. All of the cultured isolates produce substances with inhibitory activity directed at a range of potential fungal and bacterial pathogens.

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Background: A key argument in favor of conserving biodiversity is that as yet undiscovered biodiversity will yield products of great use to humans. However, the link between undiscovered biodiversity and useful products is largely conjectural. Here we provide direct evidence from bioassays of endophytes isolated from tropical plants and bioinformatic analyses that novel biology will indeed yield novel chemistry of potential value.

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