Spatial proteo-transcriptomic profiling reveals the molecular landscape of borderline ovarian tumors and their invasive progression.

Serous borderline tumors (SBT) are epithelial neoplastic lesions of the ovaries that commonly have a good prognosis. In 10-15% of cases, however, SBT will recur as low-grade serous cancer (LGSC), which is deeply invasive and responds poorly to current standard chemotherapy1,2,3. While genetic alterations suggest a common origin, the transition from SBT to LGSC remains poorly understood4. Here, we integrate spatial proteomics5 with spatial transcriptomics to elucidate the evolution from SBT to LGSC and its corresponding metastasis at the molecular level in both the stroma and the tumor. We show that the transition of SBT to LGSC occurs in the epithelial compartment through an intermediary stage with micropapillary features (SBT-MP), which involves a gradual increase in MAPK signaling. A distinct subset of proteins and transcripts was associated with the transition to invasive tumor growth, including the neuronal splicing factor NOVA2, which was limited to expression in LGSC and its corresponding metastasis. An integrative pathway analysis exposed aberrant molecular signaling of tumor cells supported by alterations in angiogenesis and inflammation in the tumor microenvironment. Integration of spatial transcriptomics and proteomics followed by knockdown of the most altered genes or pharmaceutical inhibition of the most relevant targets confirmed their functional significance in regulating key features of invasiveness. Combining cell-type resolved spatial proteomics and transcriptomics allowed us to elucidate the sequence of tumorigenesis from SBT to LGSC. The approach presented here is a blueprint to systematically elucidate mechanisms of tumorigenesis and find novel treatment strategies.

Identity-related experiences of Asian American trainees in gynecologic oncology.

Background: Anti-Asian violence increased during the COVID-19 pandemic. Asian American/Pacific Islanders (AAPI) represent a diverse population experiencing a long history of stereotyping and exclusionism; however, this group is often left out of diversity/inclusion conversations. In academic medicine, AAPI are under-represented in leadership. We characterized the personal/professional experiences of AAPI gynecologic oncology trainees and assessed the impact of a virtual panel discussion with leaders in the field. Methods: An anonymous survey was disseminated online to trainees in/interested in gynecologic oncology fellowship who identified as AAPI, using modified snowball sampling. A virtual session with AAPI leaders in gynecologic oncology discussed themes emerging from survey responses. Session attendees completed an anonymous follow-up survey. Results were assessed quantitatively and qualitatively. Results: 44/59 (75%) respondents participated in the pre-survey; 23 (39%) participated in the virtual session. All session participants (23/23, 100%) completed the post-session survey. Participants reported increased identity-related thoughts with the COVID-19 pandemic (88% during, 61% prior). Sixty-eight percent reported that identity-related thoughts/awareness changed during the pandemic. Presence of AAPI colleagues was associated with higher perceived identity-related support from their department. Of those without AAPI coworkers, none (0%) felt 'moderately' or 'extremely well supported.' Qualitative analysis demonstrated that the panel discussion created a sense of community and encouragement, combating previously reported isolation and self-consciousness. Participants reported more connection with their heritage and identified more personal/professional topics that might be related to their cultural backgrounds. Discussion: This intervention demonstrates the opportunity to provide a supportive network for mentorship and professional development in a culturally inclusive way.

Clinical outcomes in patients with COVID-19 and gynecologic cancer: A society of gynecologic oncology COVID-19 and gynecologic cancer registry study.

OBJECTIVES: Patients with gynecologic malignancies may have varied responses to COVID-19 infection. We aimed to describe clinical courses, treatment changes, and short-term clinical outcomes for gynecologic oncology patients with concurrent COVID-19 in the United States. METHODS: The Society of Gynecologic Oncology COVID-19 and Gynecologic Cancer Registry was created to capture clinical courses of gynecologic oncology patients with COVID-19. Logistic regression models were employed to evaluate factors for an association with hospitalization and death, respectively, within 30 days of COVID-19 diagnosis. RESULTS: Data were available for 348 patients across 7 institutions. At COVID-19 diagnosis, 125 patients (36%) had active malignancy. Delay (n = 88) or discontinuation (n = 10) of treatment due to COVID-19 infection occurred in 28% with those on chemotherapy (53/88) or recently receiving surgery (32/88) most frequently delayed. In addition to age, performance status, diabetes, and specific COVID symptoms, both non-White race (adjusted odds ratio (aOR) = 3.93, 95% CI 2.06-7.50) and active malignancy (aOR = 2.34, 95% CI 1.30-4.20) were associated with an increased odds of hospitalization. Eight percent of hospitalized patients (8/101) died of COVID-19 complications and 5% (17/348) of the entire cohort died within 30 days after diagnosis. CONCLUSIONS: Gynecologic oncology patients diagnosed with COVID-19 are at risk for hospitalization, delay of anti-cancer treatments, and death. One in 20 gynecologic oncology patients with COVID-19 died within 30 days after diagnosis. Racial disparities exist in patient hospitalizations for COVID-19, a surrogate of disease severity. Additional studies are needed to determine long-term outcomes and the impact of race.

Effect of risk-reducing salpingo-oophorectomy on sex steroid hormone serum levels among postmenopausal women: an NRG Oncology/Gynecologic Oncology Group study.

BACKGROUND: Risk-reducing salpingo-oophorectomy is an effective ovarian cancer risk reduction strategy. However, bilateral oophorectomy has also been associated with increased long-term nonneoplastic sequelae, effects suggested to be mediated through reductions in systemic sex steroid hormone levels. Currently, it is unclear whether the postmenopausal ovary contributes to the systemic hormonal milieu or whether postmenopausal ovarian volume or other factors, such as body mass index and age, affect systemic hormone levels. OBJECTIVE: We examined the impact of oophorectomy on sex steroid hormone levels in postmenopausal women. Furthermore, we explored how well ovarian volume measured by transvaginal ultrasound correlated with direct ovarian measures obtained during surgical pathology evaluation and investigated the association between hormone levels and ovarian volumes. STUDY DESIGN: Postmenopausal women who underwent risk-reducing salpingo-oophorectomy (180 cases) or ovarian cancer screening (38 controls) enrolled in an international, prospective study of risk-reducing salpingo-oophorectomy and risk of ovarian cancer algorithm-based screening among women at increased risk of ovarian cancer (Gynecologic Oncology Group-0199) were included in this analysis. Controls were frequency matched to the cases on age at menopause, age at study entry, and time interval between blood draws. Ovarian volume was calculated using measurements obtained from transvaginal ultrasound in both cases and controls and measurements recorded in surgical pathology reports from cases. Serum hormone levels of testosterone, androstenedione, androstenediol, dihydrotestosterone, androsterone, dehydroepiandrosterone, estrone, estradiol, and sex hormone-binding globulin were measured at baseline and follow-up. Spearman correlation coefficients were used to compare ovarian volumes as measured on transvaginal ultrasound and pathology examinations. Correlations between ovarian volumes by transvaginal ultrasound and measured hormone levels were examined using linear regression models. All models were adjusted for age. Paired t tests were performed to evaluate individual differences in hormone levels before and after risk-reducing salpingo-oophorectomy. RESULTS: Ovarian volumes measured by transvaginal ultrasound were only moderately correlated with those reported on pathology reports (Spearman rho [ρ]=0.42). The median time interval between risk-reducing salpingo-oophorectomy and follow-up for the cases was 13.3 months (range, 6.0-19.3), and the median time interval between baseline and follow-up for the controls was 12.7 months (range, 8.7-13.4). Sex steroid levels decreased with age but were not correlated with transvaginal ultrasound ovarian volume, body mass index, or time since menopause. Estradiol levels were significantly lower after risk-reducing salpingo-oophorectomy (percentage change, -61.9 post-risk-reducing salpingo-oophorectomy vs +15.2 in controls; P=.02), but no significant differences were seen for the other hormones. CONCLUSION: Ovarian volumes measured by transvaginal ultrasound were moderately correlated with volumes directly measured on pathology specimens and were not correlated with sex steroid hormone levels in postmenopausal women. Estradiol was the only hormone that declined significantly after risk-reducing salpingo-oophorectomy. Thus, it remains unclear whether the limited post-risk-reducing salpingo-oophorectomy changes in sex steroid hormones among postmenopausal women impact long-term adverse outcomes.

Gaps in patient-physician communication at the time of malignant bowel obstruction from recurrent gynecologic cancer: a qualitative study.

PURPOSE: We sought to investigate the patient and physician approaches to malignant bowel obstruction (MBO) due to recurrent gynecologic cancer by (1) comparing patient and physician expectations and priorities during a new MBO diagnosis, and (2) highlighting factors that facilitate patient-doctor communication. METHODS: Patients were interviewed about their experience during an admission for MBO, and physicians were interviewed about their general approach towards MBO. Interviews were analyzed for themes using QDAMiner qualitative analysis software. The analysis utilized the framework analysis and used both predetermined themes and those that emerged from the data. RESULTS: We interviewed 14 patients admitted with MBO from recurrent gynecologic cancer and 15 gynecologic oncologists. We found differences between patients and physicians regarding plans for next chemotherapy treatments, foremost priorities, communication styles, and need for end-of-life discussions. Both patients and physicians felt that patient-physician communication was improved in situations of trust, understanding patient preferences, corroboration of information, and increased time spent with patients during and before the MBO. CONCLUSION: Gaps in patient-physician communication could be targeted to improve the patient experience and physician counseling during a difficult diagnosis. Our findings emphasize a need for patient-physician discussions to focus on expectations for future cancer-directed treatments, support for patients at home with home health or hospice level support in line with their wishes, and acknowledgement of uncertainty while providing direct information about the MBO diagnosis.

Neoadjuvant Chemotherapy Induces Genomic and Transcriptomic Changes in Ovarian Cancer.

The growing use of neoadjuvant chemotherapy to treat advanced stage high-grade serous ovarian cancer (HGSOC) creates an opportunity to better understand chemotherapy-induced mutational and gene expression changes. Here we performed a cohort study including 34 patients with advanced stage IIIC or IV HGSOC to assess changes in the tumor genome and transcriptome in women receiving neoadjuvant chemotherapy. RNA sequencing and panel DNA sequencing of 596 cancer-related genes was performed on paired formalin-fixed paraffin-embedded specimens collected before and after chemotherapy, and differentially expressed genes (DEG) and copy-number variations (CNV) in pre- and post-chemotherapy samples were identified. Following tissue and sequencing quality control, the final patient cohort consisted of 32 paired DNA and 20 paired RNA samples. Genomic analysis of paired samples did not reveal any recurrent chemotherapy-induced mutations. Gene expression analyses found that most DEGs were upregulated by chemotherapy, primarily in the chemotherapy-resistant specimens. AP-1 transcription factor family genes (FOS, FOSB, FRA-1) were particularly upregulated in chemotherapy-resistant samples. CNV analysis identified recurrent 11q23.1 amplification, which encompasses SIK2. In vitro, combined treatment with AP-1 or SIK2 inhibitors with carboplatin or paclitaxel demonstrated synergistic effects. These data suggest that AP-1 activity and SIK2 copy-number amplification are induced by chemotherapy and may represent mechanisms by which chemotherapy resistance evolves in HGSOC. AP-1 and SIK2 are druggable targets with available small molecule inhibitors and represent potential targets to circumvent chemotherapy resistance. SIGNIFICANCE: Genomic and transcriptomic analyses identify increased AP-1 activity and SIK2 copy-number amplifications in resistant ovarian cancer following neoadjuvant chemotherapy, uncovering synergistic effects of AP-1 and SIK2 inhibitors with chemotherapy.

Differences in Sociodemographic Disparities Between Patients Undergoing Surgery for Advanced Colorectal or Ovarian Cancer.

BACKGROUND: Cytoreductive surgery (CRS) for ovarian cancer with peritoneal metastases (OPM) is an established treatment, yet access-related racial and socioeconomic disparities are well documented. CRS for colorectal cancer with peritoneal metastases (CRPM) is garnering more widespread acceptance, and it is unknown what disparities exist with regards to access. METHODS: This retrospective cross-sectional multicenter study analyzed medical records from the National Cancer Database from 2010 to 2015. Patients diagnosed with CRPM or ORP only and either no or confirmed resection were included. Patient- and facility-level characteristics were analyzed using uni- and multivariable logistic regressions to identify associations with receipt of CRS. RESULTS: A total of 6634 patients diagnosed with CRPM and 14,474 diagnosed with OPM were included in this study. Among patients with CRPM, 18.1% underwent CRS. On multivariable analysis, female gender (odds ratio [95% CI] 2.04 [1.77-2.35]; P < 0.001) and treatment at an academic or research facility (OR 1.55 [1.17-2.05]; P = 0.002) were associated with CRS. Among patients with OPM, 87.1% underwent CRS. On multivariable analysis, treatment at facilities with higher-income patient populations was positively associated with CRS, while age (OR 0.97 [0.96-0.98]; P < .0001), use of nonprivate insurance (OR 0.69 [0.56-0.85]; P = 0.001), and listed as Black (OR 0.62 [0.45-0.86]; P = 0.004) were negatively associated with CRS. CONCLUSION: There were more systemic barriers to CRS for patients with OPM than for patients with CRPM. As CRS becomes more widely practiced for CRPM, it is likely that more socioeconomic and demographic barriers will be elucidated.

Phyllodes tumor of the vulva: A case report and literature review highlighting a novel manifestation of Cowden syndrome.

Cowden syndrome is a rare hereditary cancer syndrome characterized by a germline PTEN mutation which results in an increased risk of developing breast, thyroid, and endometrial carcinoma, as well as widespread benign hamartomas. Phyllodes tumor (PT) is a rare fibroepithelial tumor that accounts for less than 1% of all breast tumors. As mammary-type glands can be found in the anogenital region, PTs can rarely arise in this location. We describe the presentation, workup and management of a PT of the vulva that developed in a patient with Cowden syndrome. This report represents the first time a vulvar PT has been described in association with Cowden syndrome and should be considered in the differential diagnosis of a slow-growing vulvar mass.

Chemotherapy response score as a prognostic tool in patients with advanced stage endometrial carcinoma treated with neoadjuvant chemotherapy.

BACKGROUND: Chemotherapy response score (CRS) applied to interval debulking specimens quantifies histopathologic response to neoadjuvant chemotherapy in patients with advanced ovarian carcinoma and correlates with progression-free and overall survival. OBJECTIVE: To investigate whether the chemotherapy response score could be applied to interval debulking specimens in patients with advanced endometrial carcinoma and be a prognostic indicator. METHODS: The study included patients with clinical stage III-IV endometrial carcinoma who received neoadjuvant chemotherapy followed by interval debulking surgery. Chemotherapy response scores were assigned to omental and adnexal metastases, and categorized as no/minimal (CRS1), partial (CRS2), and complete/near-complete (CRS3) response to neoadjuvant chemotherapy. Descriptive statistics were used to evaluate baseline characteristics and feasibility of chemotherapy response score assessment. Univariate analyses were used to evaluate associations between the chemotherapy response score, complete cytoreduction, and survival. RESULTS: This study included 40 patients. The median age was 63.5 years, and 31 patients (78%) had stage IV disease. Thirty patients had an omentectomy, 22 patients (73%) had an omental chemotherapy response score assigned. Thirty-nine patients had a bilateral salpingo-oophorectomy, 28 patients (72%) had an adnexal chemotherapy response score assigned. Omental CRS2 and CRS3 were associated with improved progression-free survival (CRS2: HR=0.18, p<0.01; CRS3: HR=0.11, p<0.01) and overall survival (CRS2: HR=0.10, p<0.01; CRS3: HR=0.16, p=0.04). Adnexal CRS2 and CRS3 were associated with improved progression-free survival (CRS2: HR=0.23, p<0.01; CRS3: HR=0.20, p=0.03). Chemotherapy response scores were also associated with an increased likelihood of having a complete cytoreduction. CONCLUSION: Chemotherapy response score can be applied to omental and adnexal metastases in patients with advanced endometrial carcinoma and was associated with survival and complete cytoreduction. The score may be a prognostic indicator and help to guide first-line treatment of patients with endometrial carcinoma.

Phase II study of intraperitoneal submicron particle paclitaxel (SPP) plus IV carboplatin and paclitaxel in patients with epithelial ovarian cancersurgery.

Submicron particles (~800 nm) of paclitaxel (SPP) contain 1-2 billion molecules of pure drug that release tumoricidal levels of paclitaxel over many weeks. This study compared two dose-levels of SPP instilled into the peritoneal cavity (IP) in 200 ml of saline post-cytoreductive surgery. Eligible patients with primary (n = 6) or recurrent (n = 4) epithelial ovarian cancer who underwent complete cytoreductive surgery were enrolled to receive a single instillation of IP SPP followed by standard IV carboplatin and paclitaxel. Endpoints were PFS and evaluation of treatment emergent adverse events. Clinical response was determined by symptoms, physical exams, CT scans, and serum CA-125 measurements. Of the 24 subjects screened, 10 were enrolled and received treatment: seven patients received 100 mg/m2 and three received 200 mg/m2. Seven subjects completed the 12-month follow-up period. Six patients were evaluable due to one subject who had unevaluable scans throughout the follow-up period and was thus excluded from PFS determination. Upon completion of planned chemotherapy post-SPP instillation, the PFS at 6 months was 66% (4/6) and at 12-months 66% (4/6) using RECIST 1.1. One subject had a complete response at the end of IV treatment but died (unrelated to study treatment) before PFS evaluation. There was one case of incision dehiscence and one case of vaginal cuff leakage after surgery. This pilot study supports further evaluation of IP SPP to treat peritoneal carcinomas.

Superior vena cava syndrome associated with uterine serous carcinoma.

•Extensive nodal metastases from uterine serous carcinoma can lead to SVC syndrome.•Prevention of nodal metastases is an important goals of care discussion.•Radiation, steroids and/or chemotherapy must all be considered in this setting.

When to Operate, Hesitate and Reintegrate: Society of Gynecologic Oncology Surgical Considerations during the COVID-19 Pandemic.

The COVID-19 pandemic has challenged our ability to provide timely surgical care for our patients. In response, the U.S. Surgeon General, the American College of Srugeons, and other surgical professional societies recommended postponing elective surgical procedures and proceeding cautiously with cancer procedures that may require significant hospital resources and expose vulnerable patients to the virus. These challenges have particularly distressing for women with a gynecologic cancer diagnosis and their providers. Currently, circumstances vary greatly by region and by hospital, depending on COVID-19 prevalence, case mix, hospital type, and available resources. Therefore, COVID-19-related modifications to surgical practice guidelines must be individualized. Special consideration is necessary to evaluate the appropriateness of procedural interventions, recognizing the significant resources and personnel they require. Additionally, the pandemic may occur in waves, with patient demand for surgery ebbing and flowing accordingly. Hospitals, cancer centers and providers must prepare themselves to meet this demand. The purpose of this white paper is to highlight all phases of gynecologic cancer surgical care during the COVID-19 pandemic and to illustrate when it is best to operate, to hestitate, and reintegrate surgery. Triage and prioritization of surgical cases, preoperative COVID-19 testing, peri-operative safety principles, and preparations for the post-COVID-19 peak and surgical reintegration are reviewed.

Approach to Palliative Care Consultation for Patients With Malignant Bowel Obstruction in Gynecologic Oncology: A Qualitative Analysis of Physician Perspectives.

PURPOSE: Malignant bowel obstruction (MBO) from gynecologic cancer is associated with increased symptoms and short survival. A gynecologic oncologist's approach to palliative care consultation in the setting of MBO has not been well studied-it could be an opportune time for collaboration with palliative care. MATERIALS AND METHODS: This qualitative analysis of interviews with gynecologic oncologists focuses on their perspectives on palliative care consultation at the time of MBO. Interviews were analyzed using a framework analysis, and key themes and quotations were extracted. RESULTS: We interviewed 15 gynecologic oncologists from 8 institutions in Chicago. They described a variety of expectations from palliative care consultation. Most frequently, they consulted palliative care for specific questions but managed the remainder of the care. Most participants frequently consulted palliative care, but they also worried about fragmentation of care, the timing of when to introduce a new team during MBO, and the selection of appropriate patients for a limited resource. Many participants preferred earlier palliative care consultation, and many described an emotional toll of caring for patients with MBO. Palliative care consultation was most readily discussed for nonsurgical patients. CONCLUSION: Participants' expectations of palliative care consultations during MBO varied and were not always met. We recommend strengthening communication and protocols for palliative care involvement that meet the needs of specific patient populations and physician teams for surgical and nonsurgical patients. More research is needed to better understand how to integrate palliative care into oncologic and surgical care with gynecologic oncologists.

Proteomics reveals NNMT as a master metabolic regulator of cancer-associated fibroblasts.

High-grade serous carcinoma has a poor prognosis, owing primarily to its early dissemination throughout the abdominal cavity. Genomic and proteomic approaches have provided snapshots of the proteogenomics of ovarian cancer1,2, but a systematic examination of both the tumour and stromal compartments is critical in understanding ovarian cancer metastasis. Here we develop a label-free proteomic workflow to analyse as few as 5,000 formalin-fixed, paraffin-embedded cells microdissected from each compartment. The tumour proteome was stable during progression from in situ lesions to metastatic disease; however, the metastasis-associated stroma was characterized by a highly conserved proteomic signature, prominently including the methyltransferase nicotinamide N-methyltransferase (NNMT) and several of the proteins that it regulates. Stromal NNMT expression was necessary and sufficient for functional aspects of the cancer-associated fibroblast (CAF) phenotype, including the expression of CAF markers and the secretion of cytokines and oncogenic extracellular matrix. Stromal NNMT expression supported ovarian cancer migration, proliferation and in vivo growth and metastasis. Expression of NNMT in CAFs led to depletion of S-adenosyl methionine and reduction in histone methylation associated with widespread gene expression changes in the tumour stroma. This work supports the use of ultra-low-input proteomics to identify candidate drivers of disease phenotypes. NNMT is a central, metabolic regulator of CAF differentiation and cancer progression in the stroma that may be therapeutically targeted.

Malignant bowel obstruction due to uterine or ovarian cancer: Are there differences in outcome?

OBJECTIVES: To describe and compare treatments and outcomes of patients with malignant bowel obstructions (MBO) due to uterine or ovarian cancer. METHODS: Retrospective chart review from two institutions of women admitted 1/1/2005-12/31/2016 with a MBO from recurrent/progressive uterine or ovarian cancer. Data collected includes patient characteristics, cancer-directed treatments before and after MBO, MBO management strategies, and survival after MBO. RESULTS: Women with MBO from uterine cancer (n = 46) and ovarian cancer (n = 130) underwent similar inpatient interventions such as inpatient chemotherapy and surgery. Median overall survival (OS) after admission for MBO for all patients was 105 days and was shorter for uterine cancer patients (57 vs 131 days, p = 0.0013). Uterine and ovarian cancer patients who had surgery had similar survival (182 vs 210 days, p = 0.6), as did those discharged on hospice from their first admission for MBO (26 vs 38 days, p = 0.1). Uterine and ovarian cancer patients had similar rates of post-discharge chemotherapy (37% vs 50%, p = 0.12), but uterine cancer patients who had chemotherapy still had shorter survival (151 vs 225 days, p = 0.03). CONCLUSIONS: MBO has a relatively poor prognosis. Ovarian and uterine cancer patients whose interventions included surgery or hospice had similar outcomes. Among patients managed medically without hospice, uterine cancer patients experienced worse survival, even when candidates for subsequent chemotherapy. Patient counseling regarding goals of care at this difficult juncture can be informed by these findings and will be enhanced by patient-reported and qualitative data on the patient experience with MBO.

Fibroblasts Mobilize Tumor Cell Glycogen to Promote Proliferation and Metastasis.

Successful metastasis requires the co-evolution of stromal and cancer cells. We used stable isotope labeling of amino acids in cell culture coupled with quantitative, label-free phosphoproteomics to study the bidirectional signaling in ovarian cancer cells and human-derived, cancer-associated fibroblasts (CAFs) after co-culture. In cancer cells, the interaction with CAFs supported glycogenolysis under normoxic conditions and induced phosphorylation and activation of phosphoglucomutase 1, an enzyme involved in glycogen metabolism. Glycogen was funneled into glycolysis, leading to increased proliferation, invasion, and metastasis of cancer cells co-cultured with human CAFs. Glycogen mobilization in cancer cells was dependent on p38α MAPK activation in CAFs. In vivo, deletion of p38α in CAFs and glycogen phosphorylase inhibition in cancer cells reduced metastasis, suggesting that glycogen is an energy source used by cancer cells to facilitate metastatic tumor growth.

Multi-level Proteomics Identifies CT45 as a Chemosensitivity Mediator and Immunotherapy Target in Ovarian Cancer.

Most high-grade serous ovarian cancer (HGSOC) patients develop resistance to platinum-based chemotherapy and recur, but 15% remain disease free over a decade. To discover drivers of long-term survival, we quantitatively analyzed the proteomes of platinum-resistant and -sensitive HGSOC patients from minute amounts of formalin-fixed, paraffin-embedded tumors. This revealed cancer/testis antigen 45 (CT45) as an independent prognostic factor associated with a doubling of disease-free survival in advanced-stage HGSOC. Phospho- and interaction proteomics tied CT45 to DNA damage pathways through direct interaction with the PP4 phosphatase complex. In vitro, CT45 regulated PP4 activity, and its high expression led to increased DNA damage and platinum sensitivity. CT45-derived HLA class I peptides, identified by immunopeptidomics, activate patient-derived cytotoxic T cells and promote tumor cell killing. This study highlights the power of clinical cancer proteomics to identify targets for chemo- and immunotherapy and illuminate their biological roles.

Second primary rhabdomyosarcoma of the uterine cervix presenting with synchronous ovarian Sertoli-Leydig cell tumor: An illustrative case of DICER1 syndrome.

•Embryonal rhabdomyosarcoma of the uterine cervix and ovarian Sertoli-Leydig cell tumors are associated with DICER1 mutation•DICER1-associated tumors should prompt genetic counseling and testing•Somatic and germline genetic mutation profiles can be used to differentiate second primary from recurrent tumors.

Immunohistochemistry for mismatch repair protein deficiency in endometrioid endometrial carcinoma yields equivalent results when performed on endometrial biopsy/curettage or hysterectomy specimens.

OBJECTIVE: Universal screening of endometrial cancer (EC) for Lynch syndrome (LS) has been increasingly implemented in the past five to ten years. Most pathologists initiate screening with immunohistochemistry (IHC) for mismatch repair proteins (MMRPs), using either pre-surgical samplings (endometrial biopsy or curettage, EMB/C) or hysterectomy specimens. We report a systematic assessment of the equivalence of IHC for LS screening on EMB/C versus hysterectomy specimens. METHODS: We identified 99 patients diagnosed with endometrioid EC and performed IHC for MMRPs MLH1, MSH2, MSH6, and PMS2 on their diagnostic EMB/C and paired hysterectomy specimen. Each specimen was scored as MMRP-retained or MMRP-deficient. RESULTS: Ninety-one EMB/Cs had carcinoma, while 8 EMB/Cs showed only complex atypical hyperplasia (CAH). Carcinoma was identified in all 99 hysterectomy specimens. Considering all 99 patients tested, concordance of MMRP expression pattern between EMB/C and paired hysterectomy specimen was 100%. Sixty-nine cases retained all four MMRPs, while 30 were MMRP deficient (26 MLH1- and PMS2-deficient, 3 MSH2- and MSH6-deficient, 1 PMS2-deficient). CONCLUSIONS: In screening for LS in EC, IHC for MMRPs can be performed with identical accuracy on either EMB/C or hysterectomy specimens. Routine testing of diagnostic EMB/Cs may lead to earlier detection of MMRP deficiency, with improved patient uptake of genetic counseling and potential for earlier identification of immunotherapy candidates. Furthermore, reliable IHC-based LS screening performed on EMB/C can guide patient management and genetic counseling in patients unable to undergo hysterectomy.

Adipocyte-induced CD36 expression drives ovarian cancer progression and metastasis.

Ovarian cancer (OvCa) is characterized by widespread and rapid metastasis in the peritoneal cavity. Visceral adipocytes promote this process by providing fatty acids (FAs) for tumour growth. However, the exact mechanism of FA transfer from adipocytes to cancer cells remains unknown. This study shows that OvCa cells co-cultured with primary human omental adipocytes express high levels of the FA receptor, CD36, in the plasma membrane, thereby facilitating exogenous FA uptake. Depriving OvCa cells of adipocyte-derived FAs using CD36 inhibitors and short hairpin RNA knockdown prevented development of the adipocyte-induced malignant phenotype. Specifically, inhibition of CD36 attenuated adipocyte-induced cholesterol and lipid droplet accumulation and reduced intracellular reactive oxygen species (ROS) content. Metabolic analysis suggested that CD36 plays an essential role in the bioenergetic adaptation of OvCa cells in the adipocyte-rich microenvironment and governs their metabolic plasticity. Furthermore, the absence of CD36 affected cellular processes that play a causal role in peritoneal dissemination, including adhesion, invasion, migration and anchorage independent growth. Intraperitoneal injection of CD36-deficient cells or treatment with an anti-CD36 monoclonal antibody reduced tumour burden in mouse xenografts. Moreover, a matched cohort of primary and metastatic human ovarian tumours showed upregulation of CD36 in the metastatic tissues, a finding confirmed in three public gene expression data sets. These results suggest that omental adipocytes reprogram tumour metabolism through the upregulation of CD36 in OvCa cells. Targeting the stromal-tumour metabolic interface via CD36 inhibition may prove to be an effective treatment strategy against OvCa metastasis.