High throughput screening identifies dasatinib as synergistic with trametinib in low grade serous ovarian carcinoma.

BACKGROUND: Low grade serous ovarian carcinoma (LGSOC) is a distinct histotype of ovarian cancer characterised high levels of intrinsic chemoresistance, highlighting the urgent need for new treatments. High throughput screening in clinically-informative cell-based models represents an attractive strategy for identifying candidate treatment options for prioritisation in clinical studies. METHODS: We performed a high throughput drug screen of 1610 agents across a panel of 6 LGSOC cell lines (3 RAS/RAF-mutant, 3 RAS/RAF-wildtype) to identify novel candidate therapeutic approaches. Validation comprised dose-response analysis across 9 LGSOC models and 5 high grade serous comparator lines. RESULTS: 16 hits of 1610 screened compounds were prioritised for validation based on >50% reduction in nuclei counts in over half of screened cell lines at 1000 nM concentration. 11 compounds passed validation, and the four agents of greatest interest (dasatinib, tyrosine kinase inhibitor; disulfiram, aldehyde dehydrogenase inhibitor; carfilzomib, proteasome inhibitor; romidepsin, histone deacetylase inhibitor) underwent synergy profiling with the recently approved MEK inhibitor trametinib. Disulfiram demonstrated excellent selectivity for LGSOC versus high grade serous ovarian carcinoma comparator lines (P = 0.003 for IC50 comparison), while the tyrosine kinase inhibitor dasatinib demonstrated favourable synergy with trametinib across multiple LGSOC models (maximum zero interaction potency synergy score 46.9). The novel, highly selective Src family kinase (SFK) inhibitor NXP900 demonstrated a similar trametinib synergy profile to dasatinib, suggesting that SFK inhibition is the likely driver of synergy. CONCLUSION: Dasatinib and other SFK inhibitors represent novel candidate treatments for LGSOC and demonstrate synergy with trametinib. Disulfiram represents an additional treatment strategy worthy of investigation.

Whole exome sequencing of low grade serous ovarian carcinoma identifies genomic events associated with clinical outcome.

OBJECTIVES: Low-grade serous ovarian carcinoma (LGSOC) is a distinct, rare, ovarian cancer type characterised by younger patient age and intrinsic chemoresistance. Understanding the molecular landscape is crucial for optimising targeted therapy. METHODS: Genomic data from whole exome sequencing of tumour tissue was analysed in a LGSOC cohort with detailed clinical annotation. RESULTS: 63 cases were analysed and three subgroups identified based on single nucleotide variants: canonical MAPK mutant (cMAPKm: 52%, KRAS/BRAF/NRAS), MAPK-associated gene mutation (MAPK-assoc: 27%) and MAPK wild-type (MAPKwt: 21%). NOTCH pathway disruption occurred across all subgroups. Tumour mutational burden (TMB), mutational signatures and recurrent copy number (CN) changes varied across the cohort with co-occurrence of chromosome 1p loss and 1q gain (CN Chr1pq) a recurrent feature. Low TMB and CN Chr1pq were associated with inferior disease-specific survival (HR 6.43; p < 0.001 and HR 3.29, p = 0.011 respectively). Stepwise genomic classification in relation to outcome resulted in four groups (TMB low; CN Chr1pq; MAPKwt/MAPKassoc; cMAPKm). 5 year disease-specific survival was 46%, 55%, 79% and 100% respectively for these groups. The two most favourable genomic subgroups were enriched for the SBS10b mutational signature, particularly the cMAPKm subgroup. CONCLUSIONS: LGSOC comprises multiple genomic subgroups with distinct clinical and molecular features. Chr1pq CN arm disruption and TMB represent promising methods to identify individuals with poorer prognosis. Further investigation of the molecular basis for these observations is required. MAPKwt cases represent around a fifth of patients. NOTCH inhibitors represent a candidate therapeutic strategy worthy of exploration across these cases.

Distinct histopathological features are associated with molecular subtypes and outcome in low grade serous ovarian carcinoma.

Low grade serous ovarian carcinoma (LGSOC) demonstrates unique clinical and molecular features compared to other ovarian cancer types. The relationship between common histological features of LGSOC and molecular events, such as hormone receptor expression patterns and MAPK gene mutation status, remains poorly understood. Recent data suggest some of these molecular features may be biomarkers of response to recently introduced biologically-targeted therapies, namely endocrine therapy and MEK inhibitors. We utilize a cohort of 63 pathologically-confirmed LGSOC cases with whole exome sequencing and hormone receptor expression data to investigate these relationships. LGSOC cases demonstrated uniformly high oestrogen receptor (ER) expression, but variable progesterone receptor (PR) expression intensity. 60% and 37% of cases demonstrated micropapillary and macropapillary patterns of stromal invasion, respectively. 63% of cases demonstrated desmoplasia, which was significantly associated with advanced disease stage and visible residual disease after cytoreductive surgery. MAPK-mutant cases (KRAS, BRAF, NRAS) more frequently demonstrated macropapillary stromal invasion, while Chr1p loss was associated with desmoplasia and low PR expression. Presence of micropapillary stromal invasion and low PR expression were associated with significantly poorer survival after accounting for stage and residual disease status. Together, these data identify novel relationships between histopathological features and molecularly-defined subgroups in LGSOC.

FARGO-360: a multi-disciplinary survey of practice and perspectives on provision of care for patients with frailty presenting with gynecological cancers in the UK and Ireland.

OBJECTIVES: Frailty has been associated with worse cancer-related outcomes for people with gynecological cancers. However, the lack of clear guidance on how to assess and modify frailty prior to instigating active treatments has the potential to lead to large variations in practice and outcomes. This study aimed to evaluate current practice and perspectives of healthcare practitioners on the provision of care for patients with frailty and a gynecological cancer. METHODS: Data were collected via a questionnaire-based survey distributed by the Audit and Research in Gynecological Oncology (ARGO) collaborative to healthcare professionals who identified as working with patients with gynecological malignancies in the United Kingdom (UK) or Ireland. Study data were collected using REDCap software hosted at the University of Manchester. Responses were collected over a 16 week period between January and April 2021. RESULTS: A total of 206 healthcare professionals (30 anesthetists (14.6%), 30 pre-operative nurses (14.6%), 51 surgeons (24.8%), 34 cancer specialist nurses (16.5%), 21 medical/clinical oncologists (10.2%), 25 physiotherapists/occupational therapists (12.1%) and 15 dieticians (7.3%)) completed the survey. The respondents worked at 19 hospital trusts across the UK and Ireland. Frailty scoring was not routinely performed in 63% of care settings, yet the majority of practitioners reported modifying their practice when providing and deciding on care for patients with frailty. Only 16% of organizations surveyed had a dedicated pathway for assessment and management of patients with frailty. A total of 37% of respondents reported access to prehabilitation services, 79% to enhanced recovery, and 27% to community rehabilitation teams. CONCLUSION: Practitioners from all groups surveyed considered that appropriate training, dedicated pathways for optimization, frailty specific performance indicators and evidence that frailty scoring had an impact on clinical outcomes and patient experience could all help to improve care for frail patients.

Are trainees working in obstetrics and gynecology confident and competent in the care of frail gynecological oncology patients?

INTRODUCTION: Older patients undergoing cancer surgery are at increased risk of post-operative complications, prolonged hospital stay, and mortality. Identification of frailty can help predict patients at high risk of peri-operative complications and allow a collaborative, multidisciplinary team approach to their care. A survey was conducted to assess the confidence and knowledge of trainees in obstetrics and gynecology regarding identification and management of peri-operative issues encountered in frail gynecological oncology patients. METHODS: A web-based survey was distributed via the Audit and Research in Gynaecological Oncology (ARGO) collaborative and UK Audit and Research Collaborative in Obstetrics and Gynaecology (UKARCOG) . The survey on the management of frail peri-operative patients was disseminated to doctors-in-training (trainees) working in obstetrics and gynecology in the United Kingdom (UK) and Ireland. Specialty (ST1-7), subspecialty, and general practice trainees, non-training grade doctors, and foundation year doctors currently working in obstetrics and gynecology were eligible. Consultants were excluded. Study data were collected using REDCAP software hosted at the University of Manchester. Responses were collected over a 6-week period between January and February 2020. RESULTS: Of the 666 trainees who participated, 67% (425/666) reported inadequate training in peri-operative management of frail patients. Validated frailty assessment tools were used by only 9% (59/638) of trainees and less than 1% (4/613) were able to correctly identify all the diagnostic features of frailty. Common misconceptions included the use of chronological age and gender in frailty assessments. The majority of trainees (76.5%, 448/586) correctly answered a series of questions relating to mental capacity; however, only 6% (36/606) were able to correctly identify all three diagnostic features of delirium. A total of 87% (495/571) of trainees supported closer collaboration with geriatricians and a multidisciplinary approach. CONCLUSIONS: Obstetrics and gynecology trainees reported inadequate training in the peri-operative care of frail gynecological oncology patients, and overwhelmingly favored input from geriatricians. Routine use of validated frailty assessment tools may aid diagnosis of frailty in the peri-operative setting. There is an unmet need for formal education in the management of frail surgical patients within the UK and Irish obstetrics and gynecology curriculum.

Pathogenesis, Genetics, and Genomics of Non-High Grade Serous Ovarian Cancers.

The 5 main non-high grade serous epithelial ovarian cancers (clear cell, low grade endometrioid, low grade serous, mucinous, and carcinosarcoma) are discrete in terms of their pathogenesis, molecular biology, and treatment sensitivity. This article reviews the current understanding of their pathogenesis and molecular biology, highlighting areas of uncertainty where future research efforts should be focused.