TP53 mutation and abnormal p53 expression in endometrial cancer: Associations with race and outcomes

OBJECTIVE

This multi-center cohort study assessed associations between race, TP53 mutations, p53 expression, and histology to investigate racial survival disparities in endometrial cancer (EC).

METHODS

Black and White patients with advanced or recurrent EC with Next Generation Sequencing data in the Endometrial Cancer Molecularly Targeted Therapy Consortium database were identified. Clinicopathologic and treatment variables were summarized by race and compared. Overall survival (OS) and progression-free survival (PFS) among all patients were estimated by the Kaplan-Meier method. Cox proportional hazards models estimated the association between race, TP53 status, p53 expression, histology, and survival outcomes.

RESULTS

Black patients were more likely than White patients to have TP53-mutated (N = 727, 71.7% vs 49.7%, p < 0.001) and p53-abnormal (N = 362, 71.1% vs 53.2%, p = 0.003) EC. Patients with TP53-mutated EC had worse PFS (HR 2.73 (95% CI 1.88-3.97)) and OS (HR 2.20 (95% CI 1.77-2.74)) compared to those with TP53-wildtype EC. Patients with p53-abnormal EC had worse PFS (HR 2.01 (95% CI 1.22-3.32)) and OS (HR 1.61 (95% CI 1.18-2.19)) compared to those with p53-wildtype EC. After adjusting for TP53 mutation and p53 expression, race was not associated with survival outcomes. The most frequent TP53 variants were at nucleotide positions R273 (n = 54), R248 (n = 38), and R175 (n = 23), rates of which did not differ by race.

CONCLUSIONS

Black patients are more likely to have TP53-mutated and p53-abnormal EC, which are associated with worse survival outcomes than TP53- and p53-wildtype EC. The higher frequency of these subtypes among Black patients may contribute to survival disparities.

Non-Redundant Mechanisms of Immune Resistance to Radiotherapy Converge on Innate Immunity

PURPOSE/OBJECTIVE(S)

Despite evidence of preclinical synergy between radiotherapy (RT) and immune checkpoint blockade (ICB), randomized trials of RT/ICB have demonstrated limited benefit in solid tumors. We performed single-cell RNA sequencing (scRNA-seq) and CITE-seq (cellular indexing of transcriptomes and epitopes) to address the discordance between preclinical and clinical data. We hypothesized that multiple orthogonal inhibitory immune pathways restrain the local and systemic efficacy of RT beyond T-cell oriented immune checkpoints.

MATERIALS/METHODS

We used the EO771 syngeneic murine model of breast cancer to characterize the immune tumor microenvironment following RT with or without ICB. RT (16 Gy x 1) was delivered using the X-RAD SmART platform with CT image guidance. Neutralizing antibodies (anti-PD-1/Ly6G/Gr-1/CD47) were delivered by intraperitoneal injections. scRNA-seq analysis were performed by Seurat and BBrowser (BioTuring).

RESULTS

We found that adaptive ICB (anti-PD-1) reprogrammed the immune response to RT by promoting an M1-like interferon-primed state (ISG15, CXCL10) in tumor associated macrophages (TAMs) and by increasing the late recruitment of intratumoral neutrophils. Given that neutrophils may drive resistance to RT in other models, we evaluated the effect of intratumoral neutrophil depletion using anti-Ly6G or anti-Gr-1 on the antitumor efficacy of RT/ICB. Both neutrophil depletion strategies led to enhanced tumor control and improved survival in advanced EO771 tumors compared to RT/ICB alone (P<0.001). In parallel to this approach, we found that TAMs upregulated several innate immune checkpoints including SIRPα in response to RT. Disruption of the SIRPα-CD47 interaction by anti-CD47 antibodies similarly enhanced the antitumor efficacy of RT/ICB by improving tumor control and survival (P<0.001). Using scRNA-seq and unbiased clustering, we found that anti-CD47 eliminated an entire cluster of chronically inflamed TAMs, characterized by pro-inflammatory markers (IL1A, NOS2) and chemokines (CCL3, CXCL1/2/3). Anti-CD47 also reduced intratumoral neutrophils by eliminating a cluster of pathologically activated neutrophils, termed myeloid-derived suppressor cells (PMN-MDSCs) that expressed several markers of ferroptosis (TFRC, PTGS2, SLC3A2). Consistent with the potent immunosuppressive capacity of PMN-MDSCs, we found that anti-CD47 increased tumor-infiltrating lymphocytes including central memory TCF7+ T cells and CD19+ B cells. Lastly, by inference and analysis of cell-cell communication (CellChat), we found that anti-CD47 strengthened the interactions between TAMs and CD8+ T cells compared to RT/ICB alone.

CONCLUSION

Our data collectively indicate that resistance to RT/ICB in the EO771 model Is driven by innate immune cells including neutrophils and chronically inflamed TAMs. Targeted disruption of the CD47-SIRPα axis is a promising approach to overcoming immune resistance by reprogramming TAMs and eliminating PMN-MDSCs.

Abstract 1255: Glucose dependent CD73+ CAFs enforce a tumor metabolic barrier that promotes T cell exclusion

Trafficking of T lymphocytes from the lymph nodes to the tumor microenvironment is a critical process of the tumor immunity cycle to elicit cytotoxic anti-tumor responses driven by CD8+ T cells. However, some tumors termed “immune excluded” recruit lymphocytes to the tumor site, but the lymphocytes are unable to penetrate the tumor parenchyma and localize primarily in the peritumoral region. In soft tissue sarcoma patients, most tumors are poorly infiltrated by T cells, which is associated with a poor response to immunotherapies. It has been described that cancer associated fibroblasts (CAFs) are enriched in immune excluded tumors and may directly block the migration of T cells via the production of dense extracellular matrix or by forging an immunosuppressive niche. We generated two models of undifferentiated pleomorphic sarcoma (UPS) that recapitulate the “immune excluded” and “inflamed” microenvironments observed in sarcoma patients. These syngeneic models rely on p53KO mesenchymal stem cells overexpressing either Ccne1 or Vgll3, which are frequently amplified in UPS patients. These models differ in their overall proportion of infiltrating TILs, and specifically T cells, making them ideal for comparative studies to investigate the mechanisms driving T cell exclusion in the TME. Using single-cell RNA-sequencing, we identified a population of CAFs expressing Nt5e, encoding CD73, which are spatially enriched in the peritumoral region of immune excluded Ccne1 tumors and closely associate with CD8+ T cells located at the tumor margin. Using transwell invasion assays, we show that CD73+ CAFs but not CD73- CAFs are able to block the migration of activated T cells towards tumor cells, even in the presence of CXCL10. Further, we show that Nt5e CAFs are enriched for signatures of glucose metabolism, and hypoxia, thus we hypothesized that CD73+ CAFs may block the migration of T cells into tumors by forging a nutrient poor metabolic barrier around the tumor. To test this, we treated Ccne1 tumors with BAY-876, a GLUT1 inhibitor and observed a significant accumulation of infiltrating CD8+ T cells compared to controls. GLUT1 treated CAFs expressed significantly less Nt5e, indicating that CD73 may play a role in the maintenance of glucose metabolism in CAFs. Furthermore, blockade of CD73 in CD73+ CAFs decreases the expression of the glucose transporter, Glut1. All together, these data suggest that CD73 may serve as a marker of glucose dependent CAFs that alter the metabolic niche to block T cell infiltration into tumors.

Citation Format: Marina Broz, Emily Ko, Jinfen Xiao, Marco DeSimone, Roberta Piras, Kristin Ishaya, Xen Ping Hoi, Jlenia Guarnerio. Glucose dependent CD73+ CAFs enforce a tumor metabolic barrier that promotes T cell exclusion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1255.

Abstract 1364: Profiling tumor microenvironment for therapeutic intervention to soft-tissue sarcomas

Soft-tissue sarcomas (STS) are mesenchymal tumors having remarkably diverse histological features. Genomic studies reported that STS have low frequencies of genetic mutation, but often harboring copy number variations (CNVs). For STS, CNVs frequently happen in essential tumor suppressor genes and oncogenic transcriptional genes, neither of which are easily “druggable” targets. Moreover, in concordance with low tumor mutation burden rate, STS show low immunogenicity with less cytotoxic TIL in the TME and is unfortunately linked to a lower responsive rate to PD1/PD-L1 ICB. Using a syngeneic mouse UPS model, we previously found that tumor-associated macrophages (TAM) in the TME are promoting the growth of sarcoma. We further identified specific tumor microenvironmental elements contributing to the pro-tumorigenicity of TAMs, which represent a promising novel clinical target for myeloid-related intervention. Therefore, we hypothesize that exploration of TME is beneficial to identify clinically promising targets for STS. To study the TME in STS, we performed bulk RNA-seq and scRNA-seq on human sarcoma samples which covered different histological subtypes of STS and compare them to normal samples. Our results show that, unlike carcinomas originating from epithelial cells, extracellular matrix (ECM)-related genes are highly upregulated in both cancer-associated fibroblast (CAF) and sarcoma tumor cells. Further analysis show that upregulation of these ECM genes is associated with a worse survival outcome in sarcoma patients. In order to further explore the STS and TME orchestra, we established several syngeneic mouse models according to the genetic aberrations reported in TCGA data. We are currently characterizing these syngeneic mouse models to find out whether they recapitulate human STS samples. Our goal is to utilize these mouse models to study the relationship of ECM-related genes in both CAF and tumor cells, find out the effect of upregulated ECM-related genes on the immune compartment in TME and search for potential therapeutic interventions.

Citation Format: Jin-Fen Xiao, Marina Broz, Roberta Piras, Kristin Ishaya, Emily Ko, Jlenia Guarnerio. Profiling tumor microenvironment for therapeutic intervention to soft-tissue sarcomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1364.

Screening tools for predicting mortality of adults with suspected sepsis: an international sepsis cohort validation study

OBJECTIVES

We evaluated the performance of commonly used sepsis screening tools across prospective sepsis cohorts in the USA, Cambodia and Ghana.

DESIGN

Prospective cohort studies.

SETTING AND PARTICIPANTS

From 2014 to 2021, participants with two or more SIRS (Systemic Inflammatory Response Syndrome) criteria and suspected infection were enrolled in emergency departments and medical wards at hospitals in Cambodia and Ghana and hospitalised participants with suspected infection were enrolled in the USA. Cox proportional hazards regression was performed, and Harrell's C-statistic calculated to determine 28-day mortality prediction performance of the quick Sequential Organ Failure Assessment (qSOFA) score ≥2, SIRS score ≥3, National Early Warning Score (NEWS) ≥5, Modified Early Warning Score (MEWS) ≥5 or Universal Vital Assessment (UVA) score ≥2. Screening tools were compared with baseline risk (age and sex) with the Wald test.

RESULTS

The cohorts included 567 participants (42.9% women) including 187 participants from Kumasi, Ghana, 200 participants from Takeo, Cambodia and 180 participants from Durham, North Carolina in the USA. The pooled mortality was 16.4% at 28 days. The mortality prediction accuracy increased from baseline risk with the MEWS (C-statistic: 0.63, 95% CI 0.58 to 0.68; p=0.002), NEWS (C-statistic: 0.68; 95% CI 0.64 to 0.73; p<0.001), qSOFA (C-statistic: 0.70, 95% CI 0.64 to 0.75; p<0.001), UVA score (C-statistic: 0.73, 95% CI 0.69 to 0.78; p<0.001), but not with SIRS (0.60; 95% CI 0.54 to 0.65; p=0.13). Within individual cohorts, only the UVA score in Ghana performed better than baseline risk (C-statistic: 0.77; 95% CI 0.71 to 0.83; p<0.001).

CONCLUSIONS

Among the cohorts, MEWS, NEWS, qSOFA and UVA scores performed better than baseline risk, largely driven by accuracy improvements in Ghana, while SIRS scores did not improve prognostication accuracy. Prognostication scores should be validated within the target population prior to clinical use.

The frequency and persistence of lymphedema diagnosis and self-reported symptoms over 5 years in patients with endometrial carcinoma

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Numbness, aching, and poor physical function were commonly reported symptoms in endometrial cancer patients.

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Lymphedema symptoms that develop soon after diagnosis of endometrial cancer can persist for at least 5 years.

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Lymphedema symptoms could develop up to 7 years after initial diagnosis or treatment for endometrial cancer.

A potentially debilitating sequela of diagnosis or treatment for endometrial cancer islower limb lymphedema (LLL), which can have significant impacts on quality of life. Theobjective of this study was to determine the frequency of LLL symptoms in uterinecancer survivors over a 5-year study period. An IRB-approved prospective study of quality of life of endometrial cancer patients whounderwent surgical intervention was undertaken. The Gynecologic CancerLymphedema Questionnaire (GCLQ) was used to survey patients in 2011 and again in2016 to evaluate for symptoms of LLL.205 patients initially answered the survey, and 75 patients completed the follow upsurvey as well, with no differences in demographics between the cohorts. 90.7% ofpatients underwent lymph node dissection. Patients commonly reported symptoms ofnumbness (66.83%), aching (54.2%), and poor physical function (47.8%). On initialsurvey, 14.7% (n = 11) of patients met criteria for LLL by GCLQ criteria, with 8 patientsreporting improvement in symptoms and 3 reporting persistent diagnosis at follow up. At follow up survey, 12.0% (n = 9) patients meeting criteria five years later, with 6patients newly meeting criteria. The most persistent symptoms were poor physicalfunction (70.6%), numbness (72.5%), general swelling (55.6%), aching (64.1%), andlimb-related swelling (60%).While the rate of LLL was similar to previous reports, there were a number of newdiagnoses of LLL at interval follow up distant from surgery, up to 7 years later.Symptoms of LLL also persisted for many years after diagnosis.

Emergency department utilization by gynecologic cancer patients during the COVID-19 pandemic: unintended improvements in the selective use of emergency care?

Objectives:

To evaluate the effects of the COVID-19 pandemic on emergency department (ED) utilization by gynecologic oncology patients in a large academic cancer center.

Methods:

Institutional data were captured from the EMR for the first 4 months of the US COVID-19 pandemic (March-June 2020) and compared to a historical control (March-June 2019). Data were collected from three major hospitals within an urban academic health system. Patients were identified as those with a gynecologic cancer diagnosis and active treatment (chemotherapy and/or radiation) within the prior 180 days of ED encounter, with an outpatient oncology visit within the last 90 days. Data including number and location of emergency department visits, admission outcomes, primary ICD-10 emergency department diagnosis, payer type, and patient demographics were collected. Descriptive statistics were performed.

Results:

Gynecologic oncology patients were significantly less likely to present to the ED for care during the first 4 months of COVID-19 (n=91) when compared to a historical control (n=144), p<0.01. Patients presenting during COVID were more likely to be admitted (43/91 vs 47/144, p<0.01), and to be kept for observation (18/43 vs 8/47, p=0.01). Of patients who were admitted, those presenting during COVID were significantly more likely to require an ICU stay during admission (12/43 vs 5/47, p=0.04). Six patients admitted during COVID (14%) died during their admission, while 3 patients (6%) died in the control group. There were no differences with respect to race, payor type, diagnosis, length of stay, or need for procedures when comparing patients admitted during COVID versus the control group. Four patients were COVID 19 positive during admission, which contributed to 1 patient death. Utilization of the health system's outpatient oncology urgent care center remained unchanged during COVID-19 (n=19 vs. n=15, p=0.43).

Conclusions:

Fewer gynecologic cancer patients presented to the ED during the COVID-19 pandemic, and those presenting had increased rates of indicated and complex care requirements. The concurrent stability in the outpatient urgent care center volume highlights a potential role for more stringent patient triaging to improve healthcare utilization in this vulnerable population going forward.

Sources of Palliative Care Knowledge Among Patients With Advanced or Metastatic Gynecologic Cancer

CONTEXT

A minority of patients with advanced or metastatic gynecologic cancer utilize palliative care and lack of knowledge may be a barrier to receiving palliative care services.

OBJECTIVES

To identify sources used by patients with advanced or metastatic gynecologic cancer to learn about palliative care and evaluate for differences in knowledge about palliative care and palliative care utilization by knowledge source.

METHODS

Patients with gynecologic cancer receiving treatment for advanced or metastatic gynecologic cancer at a single academic medical center were surveyed about their awareness of and knowledge about palliative care. Medical chart review was conducted.

RESULTS

Of the 111 women surveyed, 70 had heard of palliative care (63%). Sixty-eight specified from where they learned of palliative care: cancer care (n = 28; 41.2%), word of mouth (n = 26; 38.2%), work (n = 6; 8.8%), self-education (n = 4; 5.9%), personal experience (n = 2; 2.9%), or do not know (n = 2; 2.9%). Knowledge about palliative care (P = 0.35) and palliative care utilization (P = 0.81) did not differ by awareness of palliative care.

CONCLUSION

Most women receiving treatment for advanced gynecologic cancer have heard of palliative care from sources other than their cancer care providers. Knowledge about palliative care and source of knowledge about palliative care were not associated with palliative care utilization. Awareness of palliative care and palliative care utilization may be improved by increasing the low rate of health provider-based education and engaging cancer patients' social networks.