The elucidation of species-specific receptor pharmacology: a case study using subtype selective para- and meta-carborane estrogen receptor agonists.

Estrogen receptors are essential pharmacological targets for treating hormonal disorders and estrogen-dependent malignancies. Selective activation of estrogen receptor (ER) ß is hypothesized to provide therapeutic benefit with reduced risk of unwanted estrogenic side-effects associated with ERα activity. However, activating ERß without activating α is challenging due to the high sequence and structural homology between the receptor subtypes. We assessed the impact of structural modifications to the parent compound OSU-ERß-12 on receptor subtype binding selectivity using cell-free binding assays. Functional selectivity was evaluated by transactivation in HEK-293 cells overexpressing human or murine estrogen receptors. In vivo selectivity was examined through the uterotrophic effects of the analogs after oral administration in estrogen-naïve female mice. Furthermore, we evaluated the in vivo pharmacokinetics of the analogs following single dose IV and oral administration. Regarding selectivity, a single compound exhibited greater functional selectivity than OSU-ERß-12 for human ERß. However, like others in the meta-carborane series, its poor in vivo pharmacokinetics limit its suitability for further development. Surprisingly, and at odds with their pharmacokinetic and in vitro human activity data, most analogs potently induced uterotrophic effects in estrogen-naïve female mice. Further investigation of activity in HEK293 cells expressing murine estrogen receptors revealed species-specific differences in the ER-subtype selectivity of these analogs. Our findings highlight species-specific receptor pharmacology and the challenges it poses to characterizing developmental therapeutics in preclinical species. Significance Statement This study investigates para- and meta-substituted carborane analogs targeting estrogen receptors, revealing the greater selectivity of carborane analogs for human ERß compared to the mouse homolog. These findings shed light on the intricacies of using preclinical species in drug development to predict human pharmacology. The report also provides insights for the refinement and optimization of carborane analogs as potential therapeutic agents for estrogen-related disease states.

Clinical significance of initial symptoms in endometriosis-associated ovarian cancer.

Objective: Endometriosis is associated with various symptoms, but their severity varies from case to case. In this study, we investigated the reality of symptoms presented by patients with clinically early-stage endometriosis-associated ovarian cancer (EAOC) and explored the relationship between symptoms and laboratory/imaging findings, pathological findings, and prognosis. Materials and Methods: This was a retrospective case-control study of patients who received initial surgical treatment and were diagnosed with clinically early-stage EAOC, including ovarian endometrioid carcinoma (OEC), ovarian clear cell carcinoma (OCCC), and seromucinous borderline tumor (SMBT). Patients with OEC/OCCC diagnosed between 2006 and 2016 and those with SMBT diagnosed between 2006 and 2020 were included. Chi-square and Kaplan-Meier estimates were used for statistical analyses. Results: One hundred-seven patients (OEC, n=31; OCCC, n=39; SMBT, n=37) were included. Fifty-nine (55.1%) patients presented with symptoms, and the proportion of patients with OEC who presented with symptoms was significantly higher than that of others (OEC, 77.4%; OCCC, 43.6%; SMBT, 48.6%). The details of symptoms differed significantly among the pathological types (lower abdominal pain/abdominal discomfort/abnormal bleeding, OEC: 11/8/9; OCCC: 6/12/1; SMBT: 15/5/3). Only in the OEC group did symptomatic patients show significantly higher white blood cell (WBC) count and neutrophil/lymphocyte (N/L) ratio (symptomatic vs. asymptomatic, median: WBC count: 7250 vs. 5000, p=0.008; N/L ratio: 4.6 vs. 1.7, p=0.013). None of the asymptomatic patients showed recurrence during follow-up. Conclusion: Patients with EAOC show varying symptoms depending on the histological type of the tumor. Laboratory findings underlying symptoms also vary by histopathological type, which may reflect differences in the carcinogenesis process.

Development of an inducible excision system of a visual marker Ipomoea batatas Myb gene from the genome of transgenic cells.

In the plant genetic transformation process, single selection by a chemical-resistant marker gene occasionally allows the proliferation of non-transgenic cells, escaping selection pressure. The additional use of a visual marker gene is effective for accurate selection. For instance, R2R3-MYB genes are used for regulating anthocyanin biosynthesis; however, constitutive Myb expression in transgenic plants is not always desirable and may cause developmental abnormalities due to excess anthocyanin accumulation. To overcome the remaining problems in the use of Myb as a visible marker, we developed T-DNA. Ipomoea batatas Myb (IbMyb) and Cre expression cassettes were inserted between two loxP sequences, and the hygromycin phosphotransferase (HPT) and green fluorescent protein (GFP) expression cassettes were located outside of the loxP-IbMyb-Cre-loxP region. In the developed system, IbMyb and Cre were excised from the genomes of transgenic cells using heat-inducible Cre-loxP recombination. Upon heat treatment in a general incubator, green shoots emerged from purple tobacco transgenic calli that were pigmented with IbMyb expression. The excision of IbMyb from the genome of green shoots was confirmed using polymerase chain reaction (PCR) and sequencing. GFP expression was observed in the roots of the obtained green transgenic plants. We report that the system developed here operated successfully in tobacco, showing the potential to provide an easier and cheaper visual selection of transgenic cells in the genetic transformation process.