Restoring function to inactivating G protein-coupled receptor variants in the hypothalamic-pituitary-gonadal axis1.

G protein-coupled receptors (GPCRs) are central to the functioning of the hypothalamic-pituitary-gonadal axis (HPG axis) and include the rhodopsin-like GPCR family members, neurokinin 3 receptor, kappa-opioid receptor, kisspeptin 1 receptor, gonadotropin-releasing hormone receptor, and the gonadotropin receptors, luteinizing hormone/choriogonadotropin receptor and follicle-stimulating hormone receptor. Unsurprisingly, inactivating variants of these receptors have been implicated in a spectrum of reproductive phenotypes, including failure to undergo puberty, and infertility. Clinical induction of puberty in patients harbouring such variants is possible, but restoration of fertility is not always a realisable outcome, particularly for those patients suffering from primary hypogonadism. Thus, novel pharmaceuticals and/or a fundamental change in approach to treating these patients are required. The increasing wealth of data describing the effects of coding-region genetic variants on GPCR function has highlighted that the majority appear to be dysfunctional as a result of misfolding of the encoded receptor protein, which, in turn, results in impaired receptor trafficking through the secretory pathway to the cell surface. As such, these intracellularly retained receptors may be amenable to 'rescue' using a pharmacological chaperone (PC)-based approach. PCs are small, cell permeant molecules hypothesised to interact with misfolded intracellularly retained proteins, stabilising their folding and promoting their trafficking through the secretory pathway. In support of the use of this approach as a viable therapeutic option, it has been observed that many rescued variant GPCRs retain at least a degree of functionality when 'rescued' to the cell surface. In this review, we examine the GPCR PC research landscape, focussing on the rescue of inactivating variant GPCRs with important roles in the HPG axis, and describe what is known regarding the mechanisms by which PCs restore trafficking and function. We also discuss some of the merits and obstacles associated with taking this approach forward into a clinical setting.

Outcomes of minimal access retroperitoneal para-aortic lymphadenectomy in patients with locally advanced cervical cancer.

BACKGROUND: To evaluate outcomes of laparoscopic retroperitoneal para-aortic lymphadenectomy for stage 1b3-3b cervical cancer. METHODS: Pathology databases searched for all para-aortic lymphadenectomy cases 2005-2016. Descriptive statistics were used to analyse baseline characteristics, cox models for treatment affect after accounting for variables, and Kaplan Meier curves for survival (STATA v15). RESULTS: 191 patients had 1b3-3b cervical cancer of which 110 patients had Para-aortic lymphadenectomy. 8 (7.3%) patients stage 1b3, 82 (74.6%) stage 2b, and 20 (18.1%) stage 3b cervical cancer. Mean lymph node count 11.7 (SD7.6). The intra-operative and post-operative 30 day complication rates were 8.8% (CI: 4.3%, 15.7%) and 5.3% (CI: 1.9%, 11.2%) respectively.Para-aortic nodes were apparently positive on CT/MRI in 5/110 (5%) cases. Cancer was found in 10 (8.9%, CI: 4.3%, 15.7%) cases on histology, all received extended field radiotherapy. Only 2 were identified on pre-operative CT/MRI imaging. 3 of 10 suspected node-positive cases on CT/MRI had negative histology. Para-aortic lymphadenectomy led to alteration in staging and radiotherapy management in 8 (8%, CI: 3.7%, 14.6%) patients. Mean overall survival 42.81 months (SD = 31.79 months). Survival was significantly higher for women undergoing PAN (50.57 (SD 30.7) months) compared to those who didn't (31.27 (SD 32.5) months). CONCLUSION: Laparoscopic retroperitoneal para-aortic lymphadenectomy is an acceptable procedure which can guide treatment in women with locally advanced cervical cancer.

We evaluated outcomes for patients with stage 1b3-3b cervical cancer that had lymph nodes removed prior to planning their chemoradiotherapy. There were 3 groups ­ patients that had their lymph nodes removed, those that did not and those that had their procedure abandoned so didn't have their lymph nodes removed. We looked at the lymph nodes down the microscope to see if they contained cancer and compared this to their pre-operative imaging. 8 patients had a change to their staging and treatment because they were found to have cancer in the lymph nodes. We found that the keyhole procedure to remove lymph nodes is an acceptable procedure which can guide treatment in women with locally advanced cervical cancer.

Sertoli-Leydig tumor and DICER1 gene mutation: A case series and literature review.

OBJECTIVE: Sertoli-Leydig cell tumors (SLCTs) are rare neoplasms occurring in young women with 60% associated with DICER1 mutations. This is only the second published case series of patients with SLCTs with associated DICER1 gene alterations. DICER1 syndrome is a rare inherited tumor-susceptibility syndrome affecting organs such as the ovaries. We use this case series to inform readers on this increasingly important condition in gynecology. METHODS AND RESULTS: We present three young females presenting with secondary amenorrhoea, hirsutism, acne and in one case tonic-clonic seizures. All cases had high testosterone levels and an adnexal mass on ultrasound. Following surgical removal, pathology confirmed SLCTs and genetic testing followed. All three patients had DICER1 syndrome with two patients subsequently found to be related. DISCUSSION: The prevalence of DICER1 syndrome in the population is estimated to be 1 in 10 000 with a spectrum of sex cord stromal tumors affecting young women. The associated pathological classifications and management. This paper describes the DICER1 gene and the associated tumor predisposition syndrome alongside a surveillance protocol for use in clinical practice. It promotes discussion over the importance of early clinical genetics involvement in sex-cord stromal tumors and the associated difficulties in counseling in a young patient population. Genetic testing and early detection are imperative for targeted surveillance of at-risk organs to be performed but despite this there is no international guidance. The cases highlight the psychological impact of tumors in young patients and provokes an ethical discussion over DICER1 gene's inclusion in preimplantation genetics. CONCLUSIONS: DICER1 syndrome is a rare but increasingly important condition in pediatric and adolescent gynecology with a paucity of published data and case reports. This makes international consensus on management and surveillance difficult.

Robotic and laparoscopic gynaecological surgery: a prospective multicentre observational cohort study and economic evaluation in England.

OBJECTIVE: To compare the health-related quality of life and cost-effectiveness of robot-assisted laparoscopic surgery (RALS) versus conventional 'straight stick' laparoscopic surgery (CLS) in women undergoing hysterectomy as part of their treatment for either suspected or proven gynaecological malignancy. DESIGN: Multicentre prospective observational cohort study. SETTING: Patients aged 16+ undergoing hysterectomy as part of their treatment for gynaecological malignancy at 12 National Health Service (NHS) cancer units and centres in England between August 2017 and February 2020. PARTICIPANTS: 275 patients recruited with 159 RALS, 73 CLS eligible for analysis. OUTCOME MEASURES: Primary outcome was the European Organisation for Research and Treatment of Cancer Quality of Life measure (EORTC). Secondary outcomes included EuroQol-5 Dimension (EQ-5D-5L) utility, 6-minute walk test (6MWT), NHS costs using pounds sterling (£) 2018-2019 prices and cost-effectiveness. The cost-effectiveness evaluation compared EQ-5D-5L quality adjusted life years and costs between RALS and CLS. RESULTS: No difference identified between RALS and CLS for EORTC, EQ-5D-5L utility and 6MWT. RALS had unadjusted mean cost difference of £556 (95% CI -£314 to £1315) versus CLS and mean quality adjusted life year (QALY) difference of 0.0024 (95% CI -0.00051 to 0.0057), non-parametric incremental cost-effectiveness ratio of £231 667per QALY. For the adjusted cost-effectiveness analysis, RALS dominated CLS with a mean cost difference of -£188 (95% CI -£1321 to £827) and QALY difference of 0.0024 (95% CI -0.0008 to 0.0057). CONCLUSIONS: Findings suggest that RALS versus CLS in women undergoing hysterectomy (after adjusting for differences in morbidity) is cost-effective with lower costs and QALYs. Results are highly sensitive to the usage of robotic hardware with higher usage increasing the probability of cost-effectiveness. Non-inferiority randomised controlled trial would be of benefit to decision-makers to provide further evidence on the cost-effectiveness of RALS versus CLS but may not be practical due to surgical preferences of surgeons and the extensive roll out of RALS.

Immune checkpoint inhibitors efficacy across solid cancers and the utility of PD-L1 as a biomarker of response: a systematic review and meta-analysis.

Background: Immune checkpoint inhibitors (ICPI) are a tumor agnostic treatment. However, trials of their use have been site specific. Here we summarize the trial data and explore the utility of programmed death-ligand 1 (PD-L1) expression as a biomarker to direct their pan-cancer use. Method: A systematic review of literature, following PRISMA guidelines, was performed. Medline, Embase, Cochrane CENTRAL, NHS Health and Technology, and Web of Science were searched from their conception to June 2022 limited to the English language. The search terms and method were devised by a specialist medical librarian. Studies were limited to adults with solid cancers (excluding melanomas) treated with ICPIs. Only phase III randomized control trials (RCT) were included. The primary outcome was overall survival and secondary outcomes were progression free survival, PD-L1 expression, quality of life outcomes and adverse event data. Where present in eligible clinical trials, hazard ratios (HR), risk ratios (RR), standard error (SE) and 95% confidence intervals (CI) were extracted or calculated. Heterogeneity across studies was described with the use of an I2 score (Low: 25, 50%: moderate, 75% low heterogeneity). HR pools inverse variance methods were adopted by Random Effects (RE). Means were standardized across any heterogenous scale limits. Results: In total 46,510 participants were included in the meta-analysis. Overall, meta-analysis favored the use of ICPIs with an overall survival (OS) HR of 0.74 (95% CI 0.71 to 0.78). Lung cancers showed the most benefit in OS [HR 0.72 (95% 0.66-0.78)] followed by head and neck cancers [HR 0.75 (95% CI 0.66-0.84)] and gastroesophageal junction cancers [HR 0.75 (95% CI 0.61-0.92)]. ICPIs seem to be efficacious at both primary presentation and recurrence [OS HR 0.73 (95% CI 0.68-0.77)] vs. [OS HR 0.79 (95% CI 0.72 to 0.87)] respectively. Interestingly, subgroup analysis comparing studies in which most cancers demonstrated PD-L1 expression vs. those studies in which a minority of cancer demonstrated PD-L1 expression reported similar effect of ICPI use on OS; oddly the data favored ICPI use in studies with a minority of PD-L1 expression. Specifically, studies with minority PD-L1 expression had an HR 0.73 (95% CI 0.68-0.78) vs. studies with majority PD-L1 expression HR 0.76 (95% CI 0.70-0.84). This was maintained even when studies exploring the same cancer site were directly compared. Subgroup analysis was performed comparing the impact on OS subdivided by the specific ICPI used. Where meta-analysis was performed, Nivolumab led to the greatest impact [HR 0.70 (95% CI 0.64-0.77)] with Avelumab failing to reach significance [HR 0.93 (95% CI 0.80-1.06)]. However, overall heterogenicity was high (I2 = 95%). Finally, the use of ICPIs led to an improved side effect profile when compared with standard chemotherapy [RR 0.85 (95% CI 0.73-0.98)]. Conclusion: ICPIs improve survival outcomes in all cancer types. These effects are seen in the primary, recurrent, chemotherapy sensitive, chemotherapy resistant disease. These data support their use as a tumor agnostic therapy. Furthermore, they are well tolerated. However, PD-L1 as a biomarker for the targeting of ICPI use seems problematic. Other biomarkers such as mismatch repair or tumor mutational burden should be explored in randomized trials. In addition, there are still limited trials looking at ICPI use outside of lung cancer.

Musculoskeletal injuries in cross-speciality surgeons: a survey of UK-based doctors.

Musculoskeletal disorder (MSD) rates amongst surgeons are as high as 80% and injuries within the healthcare setting are an impending epidemic with a distinct lack of intervention to prevent it. The career-shortening impact this has on the cohort of highly trained workers within the National Health Service must be highlighted. This study was designed to be the first UK-based cross-speciality survey to establish the prevalence and impact of MSDs. A quantitative survey from the standardised Nordic Questionnaire was distributed compromising questions assessing the prevalence of musculoskeletal complaints in all anatomical zones. 86.5% of the surgeons reported musculoskeletal discomfort over the last 12 months, with 92% of respondents detailing issues over the last 5 years. 63% state this had an impact on their home life, with a further 86% believing their symptoms are related to posture at work. 37.5% of surgeons admitted to altering or stopping work due to MSDs. This survey demonstrates high rates of MSK injuries in surgeons with a certain subsequent impact on occupational safety and career length. Robotic surgery may be a solution to the impending problem however further research is needed with policies developed to protect our health workers.

Counselling of path_BRCA carriers who are considering risk-reducing oophorectomy.

path_BRCA 1/2 increases a woman's lifetime risk of breast and ovarian cancer. Interventions can be offered which manage cancer risk; annual breast screening from age 30, chemoprevention and, once a woman's family is complete, risk-reducing surgery. The latter is the most effective method of reducing cancer in path_BRCA carriers; salpingo-oophorectomy reduces breast and ovarian cancer, respectively, by up to 50% and 95%. Factors affecting a woman's decision to undergo risk-reducing surgery are complex; dominant factors include risks of surgery, effect on cancer outcomes and menopausal sequelae. Specific information relating to hormone replacement and non-hormonal alternatives are an important consideration for women but, are often overlooked. Informative counselling is required to enable satisfaction with the chosen intervention whilst improving survival outcomes. This review paper outlines the current data pertaining to these decision-making factors and provides a proforma to enable effective counselling.

Tachykinin Receptor-Selectivity of the Potential Glioblastoma-Targeted Therapy, DOTA-[Thi8,Met(O2)11]-Substance P.

Radiopharmaceutical development hinges on the affinity and selectivity of the biological component for the intended target. An analogue of the neuropeptide Substance P (SP), 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-[Thi8,Met(O2)11]-SP (DOTA-[Thi8,Met(O2)11]SP), in the theranostic pair [68Ga]Ga-/ [213Bi]Bi-DOTA-[Thi8,Met(O2)11]SP has shown promising clinical results in the treatment of inoperable glioblastoma. As the theranostic targeting component, modifications to SP that affect the selectivity of the resulting analogue for the intended target (neurokinin-1 receptor [NK1R]) could be detrimental to its therapeutic potential. In addition to other closely related tachykinin receptors (neurokinin-2 receptor [NK2R] and neurokinin-3 receptor [NK3R]), SP can activate a mast cell expressed receptor Mas-related G protein-coupled receptor subtype 2 (MRGPRX2), which has been implicated in allergic-type reactions. Therefore, activation of these receptors by SP analogues has severe implications for their therapeutic potential. Here, the receptor selectivity of DOTA-[Thi8,Met(O2)11]SP was examined using inositol phosphate accumulation assay in HEK293-T cells expressing NK1R, NK2R, NK3R or MRGPRX2. DOTA-[Thi8,Met(O2)11]SP had similar efficacy and potency as native SP at NK1R, but displayed greater NK1R selectivity. DOTA-[Thi8,Met(O2)11]SP was unable to elicit significant activation of the other tachykinin receptors nor MRGPRX2 at high concentrations nor did it display antagonistic behaviour at these receptors. DOTA-[Thi8,Met(O2)11]SP, therefore has high potency and selectivity for NK1R, supporting its potential for targeted theranostic use in glioblastoma multiforme and other conditions characterised by NK1R overexpression.

The WID-EC test for the detection and risk prediction of endometrial cancer.

The incidence of endometrial cancer is rising. Measures to identify women at risk and to detect endometrial cancer earlier are required to reduce the morbidity triggered by the aggressive treatment required for advanced endometrial cancer. We developed the WID-EC (Women's cancer risk IDentification-Endometrial Cancer) test, which is based on DNA methylation at 500 CpG sites, in a discovery set of cervical liquid-based cytology samples from 1086 women with and without an endometrial cancer (217 cancer cases and 869 healthy controls) with a worse prognosis (grade 3 or ≥stage IB). We validated the WID-EC test in an independent external validation set of 64 endometrial cancer cases and 225 controls. We further validated the test in 150 healthy women (prospective set) who provided a cervical sample as part of the routine Swedish cervical screening programme, 54 of whom developed endometrial cancer within 3 years of sample collection. The WID-EC test identified women with endometrial cancer with a receiver operator characteristic area under the curve (AUC) of 0.92 (95% CI: 0.88-0.97) in the external set and of 0.82 (95% CI: 0.74-0.89) in the prospective validation set. Using an optimal cutoff, cancer cases were detected with a sensitivity of 86% and a specificity of 90% in the external validation set, and a sensitivity and specificity of 52% and 98% respectively in the prospective validation set. The WID-EC test can identify women with or at risk of endometrial cancer.

Patient initiated follow-up in cancer patients: A systematic review.

Background: Patient-initiated follow-up (PIFU) is increasingly being implemented for oncology patients, particularly during the COVID-19 pandemic, given the necessary reduction in face-to-face hospital outpatient appointments. We do not know if PIFU has a positive (or negative) impact on overall, or progression free, survival. Objectives: To investigate the impact of PIFU on overall survival, progression free survival, patient satisfaction, psychological morbidity, specifically quality of life (QoL) and economic costs compared to hospital follow up (HFU), for any type of cancer. Methods: We carried out a systematic review using five electronic databases: MEDLINE, CINAHL, EMBASE, PsycInfo and Cochrane Central Register of Controlled Trials. Studies were eligible if they were controlled clinical trials comparing PIFU with another form of active follow-up. Effectiveness was assessed using the primary outcome of overall survival and secondary outcomes of progression free survival, patient satisfaction, psychological morbidity, QoL and cost effectiveness. Results: Eight studies met the inclusion criteria and were included. Only one study included survival as a primary outcome and indicated no significant differences between hospital-based follow-up and PIFU, although not adequately powered to detect a difference in survival. For secondary outcomes, few differences were found between PIFU and other forms of active follow-up. One study reported significant differences in fear of cancer recurrence between PIFU and HFU although did not reach the limit of clinical significance; in the short term, fear decreased significantly more in hospital based follow-up. Conclusion: We do not have evidence to support the impact of PIFU on survival or progression free survival. Fully powered randomized controlled trials are required to determine the full impact of PIFU in the longer term.

Provocative tests with Kisspeptin-10 and GnRH set the scene for determining social status and environmental impacts on reproductive capacity in male African lions (Panthera leo).

Understanding the hypothalamic factors regulating reproduction facilitates maximising the reproductive success of breeding programmes and in the management and conservation of threatened species, including African lions. To provide insight into the physiology and pathophysiology of the hypothalamic-pituitary-gonadal reproductive axis in lions, we studied the luteinising hormone (LH) and steroid hormone responses to gonadotropin-releasing hormone (GnRH) and its upstream regulator, kisspeptin. Six young (13.3 ± 1.7 months, 56.2 ± 4.3 kg) and four adult (40.2 ± 1.4 months, 174 ± 6 kg) male lions (Ukutula Conservation Centre, South Africa) were used in this study. Lions were immobilised with a combination of medetomidine and ketamine and an intravenous catheter was placed in a jugular, cephalic or medial saphenous vein for blood sampling at 10-min intervals for 220 min. The ten-amino acid kisspeptin which has full intrinsic activity (KP-10, 1 µg/kg) and GnRH (1 µg/kg) were administered intravenously to study their effects on LH and steroid hormone plasma concentrations, measured subsequently by ELISA and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively. Basal LH levels were similarly low between the age groups, but testosterone and its precursor levels were higher in the adult animals. Adult lions showed a significant LH response to KP-10 (10-fold) and GnRH (11-fold) administration (p < 0.05 and P < 0.001, respectively) whereas in young lions LH increased significantly only in response to GnRH. In adults alone, testosterone and its precursors steadily increased in response to KP-10, with no significant further increase in response to GnRH. Plasma levels of glucocorticoids in response to KP-10 remained unchanged. We suggest that provocative testing of LH and steroid stimulation with kisspeptin provides a new and sensitive tool for determining reproductive status and possibly an index of exposure to stress, environmental insults such as disease, endocrine disruptors and nutritional status. 272 words.

Lack of Oestrogen Receptor Expression in Breast Cancer Cells Does Not Correlate with Kisspeptin Signalling and Migration.

Kisspeptin is an anti-metastatic mediator in many cancer types, acting through its receptor, KISS1R. However, controversy remains regarding its role in breast cancer since both pro- and anti-metastatic roles have been ascribed to it. In KISS1R overexpressing triple-negative breast cancer (TNBC) cells, stimulation has been associated with increased invasion and MMP-9 expression, leading to the suggestion that hormone receptor status determines the metastatic effects of kisspeptin. To assess the veracity of this claim, we compared endogenous KISS1R signalling and physiological output in the hormone receptor-negative MDA-MB-231 and BT-20 cell lines after KP-10 (shortest active kisspeptin peptide) stimulation. MDA-MB-231 cells are metastatic when implanted in mice while BT-20 are not and remain epithelial-like. We show that both cell lines express KISS1R mRNA and respond to KP-10 by elevating calcium mobilisation. However, KP-10 stimulation induced migration of MDA-MB-231, but not BT-20 cells, in a calcium-dependent manner. Moreover, only BT-20 cells responded to KP-10 by increasing ERK phosphorylation in a ß-arrestin-dependent manner. Interestingly, both cell lines displayed different complements of ß-arrestin 1 and 2 expression. Overall, our data shows that, in TNBC, it is not universally true that kisspeptin/KISS1R stimulate migration or pro-metastatic behaviour, as divergent responses were observed in the two TNBC lines tested. Whether this divergence is related to the observed differences in ß-arrestin complements warrants further investigation and may enable further stratification of the ability of kisspeptin to influence breast tumour behaviour.

The prevalence of mismatch repair deficiency in ovarian cancer: A systematic review and meta-analysis.

Ovarian cancer (OC) is the least survivable gynecological malignancy and presents late. Five-year survival for OC is around 45% increasing the need for innovative treatments. Checkpoint inhibitors have shown significant clinical efficacy in mismatch repair deficient (MMRd) cancers and could be a powerful treatment in OC. However, their application in OC is limited due to the lack of data on the prevalence of MMRd. The aim of our study was to conduct a systematic review of the literature and meta-analysis to provide an accurate estimate of the prevalence of MMRd in OC. We followed PRISMA guidelines throughout. Studies were identified by electronic searches of Medline, Embase, Cochrane CENTRAL and Web of Science followed by citation searching. Studies not written in English were excluded. All studies were reviewed by at least two independent reviewers. Proportions of test positivity were calculated by random and fixed-effects meta-analysis models. I2 score was used to assess heterogeneity across studies. In total 54 studies were included with 17 532 analyzed for MMRd. The overall proportions of MMRd by immunohistochemistry and microsatellite instability analysis were 6.7% and 10.4%, respectively. MMRd was reported in all histotypes of epithelial OC but was most common in endometrioid OC. We estimate that on average 46.7% (95% CI: 28.8-65.4) of ovarian carcinomas showing MMRd by IHC had a germline path_MMR variant identified. OC in those with Lynch syndrome seems to present at an earlier age and stage. Studies however were generally of low quality and there was a high degree of heterogeneity. A significant minority (up to 16%) of OC displays MMRd and, therefore, could be amenable to checkpoint inhibition therapy. However, the current literature base is of limited quality and therefore high-quality prospective studies exploring MMRd in OC with the use of multimodal testing are required. In addition, trials researching efficacy of checkpoint inhibition in MMRd OC are needed.

Functional Rescue of Inactivating Mutations of the Human Neurokinin 3 Receptor Using Pharmacological Chaperones.

G protein-coupled receptors (GPCRs) facilitate the majority of signal transductions across cell membranes in humans, with numerous diseases attributed to inactivating GPCR mutations. Many of these mutations result in misfolding during nascent receptor synthesis in the endoplasmic reticulum (ER), resulting in intracellular retention and degradation. Pharmacological chaperones (PCs) are cell-permeant small molecules that can interact with misfolded receptors in the ER and stabilise/rescue their folding to promote ER exit and trafficking to the cell membrane. The neurokinin 3 receptor (NK3R) plays a pivotal role in the hypothalamic-pituitary-gonadal reproductive axis. We sought to determine whether NK3R missense mutations result in a loss of cell surface receptor expression and, if so, whether a cell-permeant small molecule NK3R antagonist could be repurposed as a PC to restore function to these mutants. Quantitation of cell surface expression levels of seven mutant NK3Rs identified in hypogonadal patients indicated that five had severely impaired cell surface expression. A small molecule NK3R antagonist, M8, increased cell surface expression in four of these five and resulted in post-translational receptor processing in a manner analogous to the wild type. Importantly, there was a significant improvement in receptor activation in response to neurokinin B (NKB) for all four receptors following their rescue with M8. This demonstrates that M8 may have potential for therapeutic development in the treatment of hypogonadal patients harbouring NK3R mutations. The repurposing of existing small molecule GPCR modulators as PCs represents a novel and therapeutically viable option for the treatment of disorders attributed to mutations in GPCRs that cause intracellular retention.

Identifying molecular mediators of the relationship between body mass index and endometrial cancer risk: a Mendelian randomization analysis.

BACKGROUND: Endometrial cancer is the most common gynaecological cancer in high-income countries. Elevated body mass index (BMI) is an established modifiable risk factor for this condition and is estimated to confer a larger effect on endometrial cancer risk than any other cancer site. However, the molecular mechanisms underpinning this association remain unclear. We used Mendelian randomization (MR) to evaluate the causal role of 14 molecular risk factors (hormonal, metabolic and inflammatory markers) in endometrial cancer risk. We then evaluated and quantified the potential mediating role of these molecular traits in the relationship between BMI and endometrial cancer using multivariable MR. METHODS: Genetic instruments to proxy 14 molecular risk factors and BMI were constructed by identifying single-nucleotide polymorphisms (SNPs) reliably associated (P < 5.0 × 10-8) with each respective risk factor in previous genome-wide association studies (GWAS). Summary statistics for the association of these SNPs with overall and subtype-specific endometrial cancer risk (12,906 cases and 108,979 controls) were obtained from a GWAS meta-analysis of the Endometrial Cancer Association Consortium (ECAC), Epidemiology of Endometrial Cancer Consortium (E2C2) and UK Biobank. SNPs were combined into multi-allelic models and odds ratios (ORs) and 95% confidence intervals (95% CIs) were generated using inverse-variance weighted random-effects models. The mediating roles of the molecular risk factors in the relationship between BMI and endometrial cancer were then estimated using multivariable MR. RESULTS: In MR analyses, there was strong evidence that BMI (OR per standard deviation (SD) increase 1.88, 95% CI 1.69 to 2.09, P = 3.87 × 10-31), total testosterone (OR per inverse-normal transformed nmol/L increase 1.64, 95% CI 1.43 to 1.88, P = 1.71 × 10-12), bioavailable testosterone (OR per natural log transformed nmol/L increase: 1.46, 95% CI 1.29 to 1.65, P = 3.48 × 10-9), fasting insulin (OR per natural log transformed pmol/L increase: 3.93, 95% CI 2.29 to 6.74, P = 7.18 × 10-7) and sex hormone-binding globulin (SHBG, OR per inverse-normal transformed nmol/L increase 0.71, 95% CI 0.59 to 0.85, P = 2.07 × 10-4) had a causal effect on endometrial cancer risk. Additionally, there was suggestive evidence that total serum cholesterol (OR per mg/dL increase 0.90, 95% CI 0.81 to 1.00, P = 4.01 × 10-2) had an effect on endometrial cancer risk. In mediation analysis, we found evidence for a mediating role of fasting insulin (19% total effect mediated, 95% CI 5 to 34%, P = 9.17 × 10-3), bioavailable testosterone (15% mediated, 95% CI 10 to 20%, P = 1.43 × 10-8) and SHBG (7% mediated, 95% CI 1 to 12%, P = 1.81 × 10-2) in the relationship between BMI and endometrial cancer risk. CONCLUSIONS: Our comprehensive MR analysis provides insight into potential causal mechanisms linking BMI with endometrial cancer risk and suggests targeting of insulinemic and hormonal traits as a potential strategy for the prevention of endometrial cancer.

Surgical management and outcomes for stage 1 malignant ovarian germ cell tumours: A UK multicentre retrospective cohort study.

OBJECTIVE: To describe the current surgical management of stage 1 malignant ovarian germ cell tumours and correlated oncological outcomes. STUDY DESIGN: We undertook a retrospective study of all stage 1 primary ovarian germ cell tumours treated in four major UK gynaecology oncology centres over 12 years. We assessed route of surgery, fertility-sparing approaches, ovarian cystectomy alone, and surgical staging and correlated these with clinical outcomes. RESULTS: Eighty-six patients were followed-up for a median of 4.4 years (IQR 4.3). The median age was 26 (range 11-47). There were 24 (27.9%) dysgerminomas, 13 (15.1%) yolk sac tumours, 10 (11.3%) mixed germ cell tumours, and 39 (45.3%) immature teratomas. Overall survival was 96.6% (OS, 95% CI 91.9-100%), with event free survival of 81.8% (EFS, 95% CI 72.5-92.3) at 5 years. The majority had fertility-sparing surgery (93%, n = 80). In a subset of patients with immature teratoma, there was no significant difference in recurrence or survival if patients underwent unilateral cystectomy only or salpingo-oophorectomy. Laparotomy was the most common approach (n = 66, 76.7%), used more frequently for larger tumours > 10 cm. Surgical staging procedures were undertaken in 42 (48.6%) patients with no significant difference in rates of staging across histological subtypes. Peritoneal biopsies were taken in 11 (12.7%), omental assessment in 40 (46.5%) and lymphadenectomy in 10 (11.6%). There was no significant difference in EFS between patients who underwent staging procedures (83%, CI 71-98%) versus those that did not (84%, CI 72-98%). There was no significant difference in the rate of staging procedures in paediatric (42.1% 8/19) and adult (57.9% 34/67) populations. CONCLUSIONS: Across all histologies and ages, the absence of surgical staging did not impact upon disease free or overall survival in this cohort. This study also raises the possibility of a role for ovarian cystectomy in immature teratoma. These findings warrant investigation in larger prospective studies.

Rescue of Cell Surface Expression and Signaling of Mutant Follicle-Stimulating Hormone Receptors.

Mutations in G protein-coupled receptors (GPCRs) underlie numerous diseases. Many cause receptor misfolding and failure to reach the cell surface. Pharmacological chaperones are cell-permeant small molecules that engage nascent mutant GPCRs in the endoplasmic reticulum, stabilizing folding and "rescuing" cell surface expression. We previously demonstrated rescue of cell surface expression of luteinizing hormone receptor mutants by an allosteric agonist. Here we demonstrate that a similar approach can be employed to rescue mutant follicle-stimulating hormone receptors (FSHRs) with poor cell surface expression using a small-molecule FSHR agonist, CAN1404. Seventeen FSHR mutations described in patients with reproductive dysfunction were expressed in HEK 293T cells, and cell surface expression was determined by enzyme-linked immunosorbent assay of epitope-tagged FSHRs before/after treatment with CAN1404. Cell surface expression was severely reduced to ≤18% of wild-type (WT) for 11, modestly reduced to 66% to 84% of WT for 4, and not reduced for 2. Of the 11 with severely reduced cell surface expression, restoration to ≥57% of WT levels was achieved for 6 by treatment with 1 µM CAN1404 for 24 h, and a corresponding increase in FSH-induced signaling was observed for 4 of these, indicating restored functionality. Therefore, CAN1404 acts as a pharmacological chaperone and can rescue cell surface expression and function of certain mutant FSHRs with severely reduced cell surface expression. These findings aid in advancing the understanding of the effects of genetic mutations on GPCR function and provide a proof of therapeutic principle for FSHR pharmacological chaperones.

Rescue of Function of Mutant Luteinising Hormone Receptors with Deficiencies in Cell Surface Expression, Hormone Binding, and Hormone Signalling.

INTRODUCTION: G protein-coupled receptor (GPCR) mutations are implicated in many diseases. Most inactivating mutations cause receptor misfolding and prevent trafficking to the plasma membrane. Pharmacological chaperones can "rescue" cell surface expression of such mutants, presumably by stabilising correct folding of the nascent protein. OBJECTIVE: Here we examine the scope of intracellularly retained luteinising hormone receptor (LHR) mutants that can be "rescued" by the pharmacological chaperone LHR-Chap, and whether this allosteric agonist can also restore the function of mutant LHRs with deficiencies in hormone binding or hormone-induced signalling. METHODS: Mutant LHRs were expressed in HEK 293-T cells. Cell surface expression/localisation, hormone binding, and hCG/LHR-Chap signalling were determined by ELISA, radioligand binding, and inositol phosphate accumulation assays, respectively. Molecular modelling predicted LHR-Chap interactions. RESULTS: LHR-Chap increased cell surface expression of a subset of retained mutants located in transmembrane helices predicted to be stabilised by LHR-Chap binding. For 3 (T4613.47I, L5024.61P, and S6167.46Y) hCG-responsiveness was increased following treatment. LHRs with mutations in the hormone-binding site (C131ECDR and I152ECDT) or in the hinge region (E354HingeK) had good cell surface expression but poor response to hormone stimulation, yet were responsive to allosteric activation by LHR-Chap. CONCLUSIONS: LHR-Chap, in addition to rescuing cell surface expression of intracellularly retained LHR mutants, can rescue function in mutant receptors with binding and signalling deficiencies that have normal cell surface expression. This demonstration of rescue of multiple elements of LHR dysfunction arising from inactivating mutations offers exceptional potential for treating patients with diseases arising from GPCR mutations in general.