Race/ethnicity and socioeconomic position in emergency department utilization in patients with hepatocellular carcinoma

Aim: Evaluate the association of race/ethnicity and socioeconomic position (SEP) on emergency department (ED) visits for patients with hepatocellular carcinoma (HCC), which may reflect access to and quality of cancer care. Materials & methods: Patients with HCC identified from a commercial multi-payer claims database between 2015 and 2018 were matched to near-neighborhood social determinants of health (SDOH) and stratified by race/ethnicity and SEP (proxied by annual household income). Analyses evaluated the effect of race/ethnicity and SEP on ED utilization, adjusting for SDOH, demographic and clinical characteristics using multivariable regression methods. Results: A total of 22,247 patients were included. Black and Hispanic patients had 43 and 18% higher ED utilization than White patients at higher-income levels (p < 0.01); these differences were nonsignificant at lower-income. Regardless of income level, Asian patients had lower ED utilization. Conclusion: Further research on the intersectionality between race/ethnicity, SEP and other SDOH may guide structural-level interventions to address health inequities.

[High-quality acceleration of the Chinese national schistosomiasis elimination programme to advance the building of Healthy China]

The goal of achieving elimination of schistosomiasis across all endemic counties in China by 2030 was proposed in the Outline of the Healthy China 2030 Plan. On June 16, 2023, the Action Plan to Accelerate the Elimination of Schistosomiasis in China (2023-2030) was jointly issued by National Disease Control and Prevention Administration and other 10 ministries, which deployed the targets and key tasks of the national schistosomiasis elimination programme in China. This article describes the progress of the national schistosomiasis control programme, analyzes the opportunities to eliminate schistosomiasis, and proposes targeted recommendations to tackle the challenges of schistosomiasis elimination, so as to accelerate the process towards schistosomiasis elimination and facilitate the building of a healthy China.

Light-Driven Radiochemistry with Fluorine-18, Carbon-11 and Zirconium-89

This review discusses recent advances in light-driven radiochemistry for three key isotopes: fluorine-18, carbon-11, and zirconium-89, and their applications in positron emission tomography (PET). In the case of fluorine-18, the predominant approach involves the use of cyclotron-produced [18F]fluoride or reagents derived thereof. Light serves to activate either the substrate or the fluorine-18 labeled reagent. Advancements in carbon-11 photo-mediated radiochemistry have been leveraged for the radiolabeling of small molecules, achieving various transformations, including 11C-methylation, 11C-carboxylation, 11C-carbonylation, and 11C-cyanation. Contrastingly, zirconium-89 photo-mediated radiochemistry differs from fluorine-18 and carbon-11 approaches. In these cases, light facilitates a postlabeling click reaction, which has proven valuable for the labeling of large biomolecules such as monoclonal antibodies (mAbs). New technological developments, such as the incorporation of photoreactors in commercial radiosynthesizers, illustrate the commitment the field is making in embracing photochemistry. Taken together, these advances in photo-mediated radiochemistry enable radiochemists to apply new retrosynthetic strategies in accessing novel PET radiotracers.

Occupational therapy in maternal health: Exploring the Barkin Index of Maternal Functioning as a potential tool

INTRODUCTION

Transitioning into the role of a mother encompasses many physical and psychosocial changes, affecting the way a woman may function. Maternal health is an emerging area of practice for occupational therapists, and therefore, screening and assessment tools to support work in this area are needed. The Barkin Index of Maternal Functioning (BIMF) is a quantitative outcome measure that is used by health professionals to assess maternal functioning. Currently, its ability to measure occupational performance is unclear.

METHODS

Utilising a mixed methods design, this study analysed the extent to which the BIMF assesses maternal function from an occupational perspective. Thirteen first-time mothers with a baby 12 months of age or younger participated in the study. Results from the BIMF were compared with themes developed from semi-structured qualitative interviews that explored the occupational experiences of first-time mothers.

FINDINGS

Seven themes were developed from the interviews. The BIMF addressed three themes, including changes to engagement in basic activities of daily living and leisure, transitioning into motherhood, emotions, self-efficacy, and social support. However, four themes were not captured by the BIMF, including changes to partner relationships, identity shift, influence of 'person' factors, and changes to social experiences in early motherhood.

CONCLUSION

Findings suggest that a new tool with a holistic perspective of mothers as occupational beings is needed to be able to identify occupational performance issues and the potential need for occupational therapy support. This study identified key experiences of occupational performance for new mothers.

Exploratory analysis of the cervix tumoral HPV antigen-specific T-cell repertoire during chemoradiation and after brachytherapy

BACKGROUND

Chemoradiation (CRT) may modulate the immune milieu as an in-situ vaccine. Rapid dose delivery of brachytherapy has unclear impact on T-cell repertoires. HPV-associated cancers express viral oncoproteins E6/E7, which enable tracking antigen/tumor-specific immunity during CRT.

METHODS

Thirteen cervical cancer patients on a multi-institutional prospective protocol from 1/2020-1/2023 underwent standard-of-care CRT with pulsed-dose-rate brachytherapy boost (2 fractions). Cervix swabs at various timepoints underwent multiplex DNA deep sequencing of the TCR-β/CDR3 region with immunoSEQ. Separately, HPV-responsive T-cell clones were also expanded ex vivo. Statistical analysis was via Mann-Whitney-U.

RESULTS

TCR productive clonality, templates, frequency, or rearrangements increased post-brachytherapy in 8 patients. Seven patients had E6/E7-responsive evolution over CRT with increased productive templates (ranges: 1.2-50.2 fold-increase from baseline), frequency (1.2-1.7), rearrangements (1.2-40.2), and clonality (1.2-15.4). Five patients had HPV-responsive clonal expansion post-brachytherapy, without changes in HPV non-responsive clones. Epitope mapping revealed VDJ rearrangements targeting cervical cancer-associated antigens in 5 patients. The only two patients with disease recurrence lacked response in all metrics. A lack of global TCR remodeling correlated with worse recurrence-free survival, p = 0.04.

CONCLUSION

CRT and brachytherapy alters the cervical cancer microenvironment to facilitate the expansion of specific T-cell populations, which may contribute to treatment efficacy.

[Practice and development of schistosomiasis control culture in China: A case of Jiangxi Province]

Schistosomiasis control is not only a disease control programme, but also a great social practice activity in China. During the evolution of national schistosomiasis control programmes, the special schistosomiasis control culture has been cultivated and developed, which contains the spiritual connotation of government-led, people-oriented, respect for science and integration of all efforts. The publication of Chairman Mao Zedong's two poems entitled "Farewell to the God of Plague" and the post-script in 1958 was a sign for the formation and development of Chinese schistosomiasis control culture, which always lead the orientation of development and practice of schistosomiasis control culture building. The schistosomiasis control culture provides powerful spiritual motivation and supports to schistosomiasis control programmes in China, and improving the building of schistosomiasis control culture is of great significance to strengthen our belief in achieving the goal of schistosomiasis elimination, mobilize all social resources, accelerate the progress towards elimination of schistosomiasis and facilitate the high-quality development of healthcare services. Chinese schistosomiasis control spirit is the refinement from the cultural connotation of the long-term schistosomiasis control programmes in China, and is the most essential and concentrated embodiment of the schistosomiasis control culture. This article describes the great significance of two poems entitled "Farewell to the God of Plague", summarizes the connotation and role of schistosomiasis control spirit, and introduces the practice, development and innovation of schistosomiasis control culture building in Jiangxi Province.

Cabozantinib plus atezolizumab in previously untreated advanced hepatocellular carcinoma and previously treated gastric cancer and gastroesophageal junction adenocarcinoma: results from two expansion cohorts of a multicentre, open-label, phase 1b trial (COSMIC-021)

Background

Cabozantinib is approved for previously treated advanced hepatocellular carcinoma (aHCC) and has been investigated in gastric cancer (GC) and gastroesophageal junction adenocarcinoma (GEJ). Atezolizumab plus bevacizumab is approved for unresectable or metastatic HCC untreated with prior systemic therapy. We evaluated efficacy and safety of cabozantinib plus atezolizumab in aHCC previously untreated with systemic anticancer therapy or previously treated GC/GEJ.

Methods

COSMIC-021 (ClinicalTrials.gov, NCT03170960) is an open-label, phase 1b study in solid tumours with a dose-escalation stage followed by tumour-specific expansion cohorts, including aHCC (cohort 14) and GC/GEJ (cohort 15). Eligible patients were aged ≥18 years with measurable locally advanced, metastatic, or recurrent disease per RECIST version 1.1. Patients received oral cabozantinib 40 mg daily and intravenous atezolizumab 1200 mg once every 3 weeks until progressive disease or unacceptable toxicity. The primary endpoint was investigator-assessed objective response rate per RECIST version 1.1.

Findings

Patients were screened between February 14, 2019, and May 7, 2020, and 61 (30 aHCC, 31 GC/GEJ) were enrolled and received at least one dose of study treatment. Median duration of follow-up was 31.2 months (IQR 28.5-32.7) for aHCC and 30.4 months (28.7-31.9) for GC/GEJ. Objective response rate was 13% (4/30, 95% CI 4-31) for aHCC and 0% (95% CI 0-11) for GC/GEJ. Six (20%) aHCC patients and three (10%) GC/GEJ patients had treatment-related adverse events resulting in discontinuation of either study drug.

Interpretation

Cabozantinib plus atezolizumab had clinical activity with a manageable safety profile in aHCC previously untreated with systemic anticancer therapy. Clinical activity of cabozantinib plus atezolizumab was minimal in previously treated GC/GEJ.

Funding

Exelixis, Inc., Alameda, CA, USA.

HPV-positive clinically advanced squamous cell carcinoma of the urinary bladder (aBSCC): A comprehensive genomic profiling (CGP) study

BACKGROUND

Advanced bladder squamous cell carcinoma (aBSCC) is an uncommon form of urinary bladder malignancy when compared with the much higher urothelial carcinoma incidence. We studied the genomic alteration (GA) landscape in a series of aBSCC based on the association with human papilloma virus (HPV) to determine if differences in GA would be observed between the positive and negative groups.

METHODS

Using a hybrid capture-based FDA-approved CGP assay, a series of 171 aBSCC were sequenced to evaluate all classes of GA. Tumor mutational burden (TMB) was determined on up to 1.1 Mbp of sequenced DNA and microsatellite instability (MSI) was determined on up to 114 loci. Programmed cell death ligand -1 (PD-L1) expression was determined by IHC (Dako 22C3) with negative expression when PD-L1 was 0, lower expression of positivity set at 1 to 49%, and higher expression set at ≥50% expression.

RESULTS

Overall, 11 (6.4%) of the aBSCC were found to harbor HPV sequences (10 HPV16 and 1 HPV 11). HPV+ status was identified slightly more often in women (NS) and in younger patients (P = 0.04); 2 female patients with aBSCC had a prior history of SCC including 1 anal SCC and 1 vaginal SCC. HPV+ aBSCC had fewer GA/tumor (P < 0.0001), more inactivating mutations in RB1 (P = 0.032), and fewer inactivating GA in CDKN2A (P < 0.0001), CDKN2B (P = 0.05), TERT promoter (P = 0.0004) and TP53 (P < 0.0001). GA in genes associated with urothelial carcinoma including FGFR2 and FGFR3 were similar in both HPV+ and HPV- aBSCC groups. MTAP loss (homozygous deletion) which has emerged as a biomarker for PRMT5 inhibitor-based clinical trials was not identified in any of the 11 HPV+ aBSCC cases, which was significantly lower than the 28% positive frequency of MTAP loss in the HPV- aBSCC group (P < 0.0001). MTOR and PIK3CA pathway GA were not significantly different in the 2 groups. Putative biomarkers associated with immunotherapy (IO) response, including MSI and TMB status, were also similar in the 2 groups. PD-L1 expression data was available for a subset of both HPV+ and HPV- cases and showed high frequencies of positive staining which was not different in the 2 groups.

CONCLUSIONS

HPV+ aBSCC tends to occur more often in younger patients. As reported in other HPV-associated squamous cell carcinomas, HPV+ aBSCC demonstrates significantly reduced frequencies of inactivating mutations in cell cycle regulatory genes with similar GA in MTOR and PIK3CA pathways. The implication of HPV in the pathogenesis of bladder cancer remains unknown but warrants further exploration and clinical validation.

Tumor-resident Lactobacillus iners confer chemoradiation resistance through lactate-induced metabolic rewiring

Tumor microbiota can produce active metabolites that affect cancer and immune cell signaling, metabolism, and proliferation. Here, we explore tumor and gut microbiome features that affect chemoradiation response in patients with cervical cancer using a combined approach of deep microbiome sequencing, targeted bacterial culture, and in vitro assays. We identify that an obligate L-lactate-producing lactic acid bacterium found in tumors, Lactobacillus iners, is associated with decreased survival in patients, induces chemotherapy and radiation resistance in cervical cancer cells, and leads to metabolic rewiring, or alterations in multiple metabolic pathways, in tumors. Genomically similar L-lactate-producing lactic acid bacteria commensal to other body sites are also significantly associated with survival in colorectal, lung, head and neck, and skin cancers. Our findings demonstrate that lactic acid bacteria in the tumor microenvironment can alter tumor metabolism and lactate signaling pathways, causing therapeutic resistance. Lactic acid bacteria could be promising therapeutic targets across cancer types.

Determining clinical perspectives and strategies for improving enrollment of minoritized communities in prostate cancer clinical trials

BACKGROUND

Black men and other minoritized populations have represented 4-5% or less of participants in most practice-informing clinical trials. This study sought to assess the knowledge, attitudes, and practices of clinicians around equity and inclusion in prostate cancer clinical trial initiatives in the United States.

METHODS

An anonymous, web-based questionnaire was administered via REDCap (Research Electronic Data Capture) with questions focused on inclusivity of minoritized populations with respect to race and ethnicity in prostate cancer clinical trials research. The survey link was distributed across the United States via several professional organizations, prostate cancer groups, and social media. Responses were analyzed both quantitatively (descriptive statistics) and qualitatively (thematic analysis).

RESULTS

Overall, 131 respondents completed the survey (70% self-identified as White, 17% as Asian, and 6% as Black). Most respondents practiced in an urban setting (89%). Of those who engaged in outreach with minoritized communities during the trial design process, 69% observed improved enrollment of minoritized populations. However, 18% of respondents noted that outreach alone does not overcome existing structural barriers to participation in clinical trials. Thematic analysis identified four key areas to address for improving equity: structural, health system, trial-/study-specific, and relationship-/engagement-related factors.

CONCLUSION

Study participants demonstrated a knowledge of the importance of improving equity in prostate cancer clinical trials research. Designing trials that reduce issues associated with access and improving community outreach were emphasized as key focus areas for reducing health disparities in prostate cancer clinical trials research.

Changes in the Abundances of Cervical and Rectal Mycobiota during Chemoradiotherapy in Cervical Cancer

PURPOSE/OBJECTIVE(S)

Globally, cervical cancer is the fourth most frequent cancer in women. The local and gut microbiomes of cervical cancer patients primarily consist of bacteria, viruses, and fungi. Bacterial composition has been previously associated with response to chemoradiotherapy (CRT) and patient outcome. Recently, our group has demonstrated that the HPV virome dynamically shifts during treatment and was associated with treatment response. Although connections between fungi and cervicovaginal health have been established, little is known about the fungal microbiome during treatment of cervical cancer. In this study, we sought to explore changes in fungal distribution throughout CRT for a cohort of cervical cancer patients.

MATERIALS/METHODS

This study includes 57 patients diagnosed with cervical cancer at a single institution with samples collected throughout CRT timepoints: baseline, week 1, week 3, and week 5. 170 swab specimens were included in this analysis: 138 cervical swabs from 56 patients and 32 rectal swabs from 9 patients. Whole genome sequencing data was obtained from the swabs using the Illumina HiSeqX platform (2 × 150bp). Fungal reads were log transformed to reduce variability and skewness and normalized to the total library size resulting in log normalized fungal reads per million (RPM). Bacterial reads were normalized with the same methodology. Timepoint analysis was performed using Wilcoxon signed rank tests or Friedman tests (with Dunn's multiple comparisons test) when comparing two or more time points, respectively.

RESULTS

All swab samples contained reads mapped to fungi. Of the 3.70 × 109 total reads across all sequenced samples, 19.2% did not map specifically to the human genome: 91.8% of these non-human reads could not be mapped to an individual microbial genome. Of the remaining 8.2% of non-human reads that mapped to a specific microbial genome (1.6% of total), 97.4% were classified as bacterial (1.5% of total), 0.71% as virus (0.011% of total), and 0.44% as fungal (0.0069% of total). Comparison of fungal RPM in the cervical and rectal microbiome revealed a significant decrease during treatment from baseline to week 5 (cervical, P = 0.0002; rectal, P = 0.0273). Distribution of bacterial reads exhibited similar trends as decreases were observed between baseline and week 5 for both cervical (P = 0.0116) and rectal (P = 0.0195) samples. Fungi to bacteria distribution ratios in the rectal microbiome revealed significant differences when comparing across all timepoints (P = 0.0041), baseline vs. week 1 (P = 0.0028), baseline vs. week 3 (P = 0.0389), and baseline vs. week 5 (P = 0.0113) with all three later timepoints higher relative to baseline.

CONCLUSION

The distributions of cervical and gut fungal reads and their relationship to the bacteriome shift during CRT. Further investigation into characterizing fungi and their relationship with other microbiota will be valuable to understanding its potential associations with cervical cancer and treatment response.

Proton Radiation Therapy for Stage IIA/IIB Testicular Seminoma

PURPOSE/OBJECTIVE(S)

Testicular seminoma affects young men and is associated with very favorable prognosis. The evolution in treatment paradigm has focused on minimizing acute and especially late toxicities. Following orchiectomy, while surveillance is favored in Stage I patients, radiotherapy (RT) is a standard treatment option for de novo or relapsed stage IIA or select non-bulky stage IIB disease. Despite low doses, standard RT fields to paraaortic and pelvic lymphatics using x-rays exposes a large volume of uninvolved normal tissue/viscera to excess dose. This young patient population is especially vulnerable to risks of late RT toxicities including secondary malignancy. Proton beam therapy (PBT) has dosimetric advantage over x-ray-based RT due to lack of exit dose, and comparative dosimetric/modeling studies show significant sparing of uninvolved abdominal/pelvic organs. However, there is scant reported clinical data at this time for PBT. We review our early institutional outcomes with PBT for testicular seminoma.

MATERIALS/METHODS

Single institution retrospective review from a tertiary care center of patients treated with PBT from 2013-2022 for testicular seminoma. Recurrence free (RFS) and overall survival (OS) were calculated from the completion of PBT. Toxicities were graded (Gr) using CTCAE v5.0.

RESULTS

Four patients underwent PBT, median age 39 (range 36-47). All were Stage I at diagnosis (pT1b n = 3; pT2 n = 1) and were treated for recurrent stage II disease (IIA n = 3; IIB n = 1) at a median of 34 months from orchiectomy (range 3 - 74 months). Nodal extent included 2 with multiple paraaortic nodes, 1 with solitary paraaortic node and 1 with solitary pelvic node. PBT was delivered with pencil-beam scanning, treating paraaortic + ipsilateral pelvic fields (20 Gy in 10 fractions), then sequential boost to involved nodes (10 -16 Gy in 5-8 fractions). Typically, PA or posterior oblique fields were used to minimize dose to out-of-field abdominal/pelvic viscera. Treatment was well tolerated with minimal acute toxicities: fatigue Gr 1 (n = 3), nausea Gr 1 (n = 3). No Gr 2 or higher acute toxicities or significant late toxicities were observed. At median follow up of 30 months (range 3 - 54), no recurrences were observed, and RFS and OS were 100%. Two patients are without evidence of disease > 4 years post-treatment.

CONCLUSION

In this case series, PBT for retroperitoneal and pelvic metastases in Stage IIA/IIB testicular seminoma was associated with oncologic efficacy with minimal toxicity. PBT reduces unnecessary dose to abdominal/pelvic organs compared to x-ray techniques, which is advantageous in young patients who have anticipated long-term survival. This is one of the few series reporting clinical outcomes of PBT in the management of seminoma. Randomized comparisons with x-ray approaches are impractical given the relatively low volume of patients receiving RT in modern seminoma management, so it is essential to report and track longitudinal outcomes across institutions to validate this approach.

Early Outcomes of MR-Guided SBRT for Patients with Recurrent Pancreatic Adenocarcinoma

PURPOSE/OBJECTIVE(S)

Local treatment options for patients with locally recurrent pancreatic adenocarcinoma (L-PAC) are limited, with expected median survival time (MST) of 8-11 months (mo) following recurrence. MRI-guided radiation therapy (MRgRT) provides the ability to dose escalate while sparing normal tissue. The literature for MR-guided Stereotactic Body Radiotherapy (MRgSBRT) for L-PAC is sparse. Here we report on the early outcomes of MRgSBRT in patients with L-PAC.

MATERIALS/METHODS

Patients with prior resection of pancreatic adenocarcinoma with post-operative chemotherapy as indicated followed by local recurrence of disease at prior surgical site and treated with MRgSBRT at a single tertiary referral center from 5-2021 to 8-2022 for L-PAC were identified from our prospective database. MRgSBRT was delivered to 40-50 Gy in 4-5 fractions with target and OAR delineation per institutional standards. Descriptive analysis of the patient, disease, and treatment characteristics were performed. Endpoints included local control, defined as absence of tumor progression per RECIST criteria, distant failure, overall survival (OS), and acute and chronic toxicities per Common Terminology Criteria for Adverse Events (CTCAE), version 5.

RESULTS

Eleven patients with L-PAC were identified with median follow-up of 10.7 mo (3.2 - 22.3). Ten of those underwent surgical resection at the treating radiation facility and one patient underwent preoperative radiation for 50.4 Gy in 28 fractions followed by surgical resection at an outside hospital. MRgRT was delivered a median of 18.8 mo (3.5 - 48.0) following resection. There were 5 females and 6 males, with a median age of 72 years (52-83) and median KPS of 80 (60-100). OS rates following initial diagnosis at 12, 18 and 24 mo were 100%, 82%, and 61%, respectively, with an MST of 25.3 mo (12.4-53.1). OS rates following recurrence at 6 and 12 mo were 82% and 52%, respectively, with an MST of 10.7 mo (3.2 - 21.9). One patient experienced local failure at 7.8 mo, and 9 patients experienced distant failure at a median of 3.4 mo (0.3 - 21.9) following MRgSBRT. Five patients experienced distant failure less than 3 mo following radiation. Grade 1 or 2 acute GI toxicity was noted in 45% of patients and chronic GI toxicity, in 18% of patients. No Grade≥3 AEs were noted.

CONCLUSION

MRgSBRT for recurrent pancreatic adenocarcinoma demonstrates good local control with acceptable acute and chronic toxicity as well as reasonable overall survival. Distant failure remains a substantial problem with a significant number of patients demonstrating metastases immediately following radiation, suggesting the presence of micro-metastatic disease prior to local therapy. Adequate patient selection for MRgSBRT, and proper integration of systemic therapy in this patient population remains a topic of discussion that requires further exploration.

Association of Bacterial Composition and Diversity in the Cervical Tumor Microbiome with HPV Genotype in a Large, International Patient Cohort

PURPOSE/OBJECTIVE(S)

Tumor bacterial composition is strongly associated with response to cancer therapy, and is impacted by environment, including geography. Human papillomavirus (HPV) genotypic diversity composition and load are dynamic during pelvic radiation (RT) and correlate with differential responses to RT in cervical cancer patients. In this multi-institutional, collaborative study, we aimed to explore associations between bacterial composition, HPV serotypes, and geographical distribution in an international patient population.

MATERIALS/METHODS

Cervical swabs were collected from 287 patients diagnosed with cervical cancer/ dysplasia in four locations: Houston, USA (TX; N = 94), Ethiopia (ETH; N = 85), Puerto Rico (PR; N = 71), and Botswana (BOT; N = 37). Swabs were collected prior to treatment and were subjected to 16S V4 rRNA gene sequencing and HPV genotyping. We compared HPV types and geography via Chi-squared test. We analyzed bacterial composition, alpha diversity (ANOVA), and beta diversity (principal coordinates analysis [PCoA] with PERMANOVA) for HPV type and geography. We used Linear Discriminant Effect Size (LEfSe) analysis to distinguish taxa associated with HPV types.

RESULTS

Overall, the global bacterial composition for patients with cancer or dysplasia did not significantly vary by location. However, the proportion of patients with each HPV type varied by location (p<0.01); HPV16 was most frequent in TX (54%), BOT (70%) and ETH (61%), while HPV18 was most frequent in PR (62%). The proportion of patients with HPV low-risk/negative tumors was highest in ETH (25%) compared to other sites (2% - 14%). Patients with HPV 16 had significantly higher bacterial alpha diversity across locations (all p<0.01). The bacterial composition also differed by HPV type across locations (p = 0.01). On LEfSe, bacterial genera enriched in HPV 16 samples were Bacteroides, Clostridium, and Prevotella. Non-HPV16 tumors were enriched in species of Lactobacillus and Gardnerella and HPV 18 and high-risk type tumors were enriched in Escherichia.

CONCLUSION

In thislarge, international cohort of cervical cancer and dysplasia patients, bacterial composition was more closely associated with cervical HPV genotype than with geography. This finding has implications for the development of biomarkers and interventions aimed at improving chemotherapy and radiation response through manipulation of the microbiome.

Recent Advances in Visible Light-Mediated Radical Fluoro-alkylation, -alkoxylation, -alkylthiolation, -alkylselenolation, and -alkylamination

In the last few years, many reagents and protocols have been developed to allow for the efficient fluorofunctionalization of a diverse set of scaffolds ranging from alkanes, alkenes, alkynes, and (hetero)arenes. The concomitant rise of organofluorine chemistry and visible light-mediated synthesis have synergistically expanded the fields and have mutually benefitted from developments in both fields. In this context, visible light driven formations of radicals containing fluorine have been a major focus for the discovery of new bioactive compounds. This review details the recent advances and progress made in visible light-mediated fluoroalkylation and heteroatom centered radical generation.

Genomic characterization of early-stage hepatocellular carcinoma patients with Hepatitis B using circulating tumor DNA

BACKGROUND

Hepatocellular carcinoma (HCC) is a leading cause of mortality, with Hepatitis B virus (HBV) infection as a dominant etiology worldwide. Effective early detection strategies may facilitate curative therapies and improve survival. We investigated genomic aberrations in circulating tumor DNA (ctDNA) as potential diagnostic markers of HCC in HBV-infected patients.

METHODS

We identified early stage (BCLC 0-A) HCC cases (n = 21) and patients without HCC (n = 14) from a cohort of Asian patients with HBV, undergoing surveillance between 2013 and 2017. Circulating cell-free DNA was isolated from blood samples, and assayed by next-generation sequencing of 23 genes implicated in HCC pathogenesis. Somatic mutations were identified using a computational pipeline. Using area under the curve (AUC) in receiver operating characteristic (ROC) analysis, we evaluated gene alterations and clinical factors in an exploratory early HCC detection model.

RESULTS

Mutant ARID1A, CTNNB1, TP53 genes were increased in HCC cases vs. non-HCC patients (85.7% vs 42.9%, P = 0.011; 42.9% vs 0%, P = 0.005; 100% vs 71.4%, P = 0.019, respectively). Using these three genes, AUC for discriminating HCC from non-HCC patients was 0.844 (95% confidence interval [CI]: 0.7317-0.9553). When combining these genes with clinical factors in an exploratory early HCC detection model, AUC increased from 0.7415 (using clinical factors alone) to 0.9354 (P = 0.041).

CONCLUSION

Genomic aberrations in ctDNA were more prevalent in HBV-infected HCC patients compared with patients without HCC. Combining these alterations with clinical factors may identify HCC in HBV-infected patients at an early stage. These findings warrant validation in future studies.

[Primary α-fetoprotein positive hepatoid adenocarcinoma of the lung: a case report]

This paper reports the data of a patient who was admitted to hospital for "cough with blood in sputum for 6 months" and diagnosed with α-fetoprotein(AFP) positive primary hepatoid adenocarcinoma of the lung. The patient was an 83-year-old male with a history of smoking for more than 60 years. Tumor indicators of patients were: AFP>3 000 ng/ml, carcinoembryonic antigen(CEA) 31.5 ng/ml, CA724 46.90 U/ml, Cyfra21-1 10.20 ng/ml, NSE 18.50 ng/ml, and the pathological findings of percutaneous lung biopsy showed that poorly differentiated cancer with significant necrosis. Combined with the results of immunohistochemistry and clinical laboratory examination, it is considered as metastatic hepatocellular carcinoma. PET-CT showed that FDG metabolism of multiple lymph nodes in the right lower lung, part of the pleura and mediastinum was increased, and the FDG metabolism in the liver or other systems/tissues was normal. Based on these results, it was diagnosed as AFP positive primary hepatoid adenocarcinoma of the lung, and the tumor stage was T4N3M1a(IVA). Through the data of the patient and the existing literature and reviews, we can get the tumor characteristics, diagnosis, treatment and prognosis of HAL, and improve the level of diagnosis and treatment of HAL by clinicians.

Photoredox Catalysis for the Synthesis of N-CF2H Compounds Using 1-((N-(difluoromethyl)-4-methylphenyl)-sulfonamido)pyridin-1-ium Trifluoromethanesulfonate

: N-(difluoromethyl)amino (-NCF2H) compounds are of great interest given their unique and underexplored physiochemical properties. The lack of structural diversity in NCF2H compounds is likely due in part to the shortage of protocols for efficient installation. Presented herein is a new shelf-stable pyridinium reagent that enables the direct installation of the N-(difluoromethyl)sulfonamide moiety [N(Ts)CF2H)] onto (hetero)arenes and alkenes for the diversification of aryl and alkyl NCF2H compounds. The described protocol utilizes blue light photoredox catalysis and displays broad functional group tolerance with excellent chemoselectivity. Additional transformations and applicability towards a photoredox continuous flow protocol are also demonstrated.

Quality-adjusted time without symptoms or toxicity analysis of nivolumab plus chemotherapy versus chemotherapy alone for the management of previously untreated patients with advanced gastric cancer, gastroesophageal junction cancer, or esophageal adenocarcinoma

BACKGROUND

The phase 3 CheckMate 649 established superior overall survival of nivolumab in combination with chemotherapy (NIVO + chemo) compared with chemotherapy (chemo) alone as a first-line treatment for patients with Her2-negative advanced gastric cancer, gastroesophageal junction cancer, and esophageal adenocarcinoma (GC/GEJC/EAC). This post hoc trial analysis aimed to evaluate the benefit of NIVO + chemo using quality-adjusted time without symptoms or toxicity (Q-TWiST) to further account for quality of life (QoL) in different health states depending on disease progression and treatment toxicity.

METHODS

Using data from CheckMate 649, we evaluated the quality-adjusted survival gain associated with NIVO + chemo compared with chemo alone among all randomized patients and repeated similar analyses among those with programmed cell death-ligand 1 (PD-L1) combined positive score (CPS) ≥ 5. Relative Q-TWiST gains of ≥ 10% were predefined as clinically important.

RESULTS

In all randomized patients, those receiving NIVO + chemo had a mean Q-TWiST gain of 1.8 (95% CI 0.9, 2.7) months compared with those receiving chemo alone. The relative Q-TWiST gain was estimated to be 12.8%. Patients with PD-L1 CPS ≥ 5 had greater quality-adjusted survival gain from NIVO + chemo with an estimated Q-TWiST gain of 2.8 (95% CI 1.5, 4.1) months, representing a relative gain of 20.6%. Subgroup analyses and sensitivity analyses with various QoL utility values yielded consistent findings in favor of NIVO + chemo compared with chemo alone. Q-TWiST gain from NIVO + chemo increased with longer duration of follow-up.

CONCLUSIONS

NIVO + chemo was associated with a statistically significant and clinically important gain in quality-adjusted survival compared with chemo alone among previously untreated patients with advanced GC/GEJC/EAC.

Abstract 1096: Single cell transcriptomic sequencing of pancreatic ductal adenocarcinoma reveals an enrichment of immunosuppressive pathways in patients at high risk for early local progression following stereotactic body radiation therapy

Patients with locally advanced pancreatic ductal adenocarcinoma (PDAC) have limited therapeutic options with their disease being defined as neither metastatic nor amenable to surgical resection. Although stereotactic body radiation therapy (SBRT) is a viable treatment option in this context, disease progression remains far too common in PDAC. Understanding the interaction between radiation, cancer cells, and the tumor microenvironment (TME) may lead to an understanding of novel resistance pathways that can be exploited.

In order to identify these potential nodes of therapeutic actionability, we leveraged a phase I/II dose escalation clinical trial of SBRT with a radiomodulating agent, GC4419, undertaken in patients with locally advanced PDAC. In this trial, core biopsies were obtained following neoadjuvant chemotherapy, but before and after SBRT with 50-60Gy in 5 fractions. A total of 16 biopsies underwent single cell RNA sequencing with 7 patients with matched samples before and after radiation.

Of the 7 matched patients, a total of 3 experienced early local progression following SBRT, and were deemed to be nonresponders. We observed a significant increase in NK-like cells and a decrease in B-cells and Mast cells following SBRT in nonresponders. On the other hand, we also observed a significant enrichment in pathways related to downregulation of innate immunity within macrophage populations following SBRT suggesting that an immunosuppressive microenvironment may prevail in these patients. Subsequently, we observed functionally distinct cancer-associated fibroblasts (CAFs) subtypes, including myofibroblastic, inflammatory, and antigen presenting CAFs (apCAF). ApCAFs are believed to be involved in antigen presentation to CD4 T cells, but lack the costimulatory molecules to activate immune response, and are thus presumed to contribute to an immunosuppressive microenvironment through anergy. Interestingly, the population of apCAFs decreased significantly following SBRT in non-responders, and increased in those patients deemed to be responders. Thus whether apCAFs have an additional inflammatory role in the setting of patients receiving radiation remains to be further understood.

We have shown how single cell RNA sequencing can be used to profile the kinetics of cell populations following SBRT. This has revealed an interplay between members of the tumor microenvironment whereby immunosuppressive pathways appear to prevail over immunostimulatory signals in nonresponders. Understanding which pathways are enriched in those patients at highest risk for local recurrence may provide insight into novel therapeutic strategies that can be implemented concurrently with radiation therapy.

Citation Format: Vincent Bernard, Adnan Elhammali, Daniel Lin, Ching-Wei Tzeng, Manoop S. Bhutani, Cullen Taniguchi. Single cell transcriptomic sequencing of pancreatic ductal adenocarcinoma reveals an enrichment of immunosuppressive pathways in patients at high risk for early local progression following stereotactic body radiation therapy [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 1096.

Use of Monitoring Tests Among Patients With Localized Prostate Cancer Managed With Observation

PURPOSE

It is unknown whether compliance with recommended monitoring tests during observation of localized prostate cancer has changed over time.

MATERIALS AND METHODS

We performed a retrospective cohort study of Medicare beneficiaries diagnosed with low- or intermediate-risk prostate cancer in 2004-2016 who were initially managed with observation for a minimum of 12 months. The primary objective was to examine rates of PSA testing, prostate biopsy, and prostate MRI. We used multivariable mixed effects Poisson regression to determine whether rates of PSA testing and prostate biopsy increased over time. In addition, we identified clinical, sociodemographic, and provider factors associated with the frequency of monitoring tests during observation.

RESULTS

We identified 10,639 patients diagnosed at a median age of 73 (IQR 69-77) years. The median follow-up time was 4.3 (IQR 2.7-6.6) years after diagnosis. Among patients managed without treatment for 5 years, 98% received at ≥1 PSA test, 48.0% ≥1 additional prostate biopsy, and 31.0% ≥1 prostate MRI. Among patients managed with observation for ≥12 months, mixed effects Poisson regression revealed that rates of PSA testing and biopsy increased over time (per calendar year: RR 1.02, 95% CI: 1.02-1.03 and RR 1.10, 95% CI: 1.08-1.11, respectively). Clinical and sociodemographic factors including age, clinical risk, race/ethnicity, census tract poverty, and region were associated with rates of biopsy and PSA testing.

CONCLUSIONS

Use of recommended monitoring tests including repeat prostate biopsy remains low among Medicare beneficiaries undergoing observation for low- and intermediate-risk prostate cancer.

HPV-related anal cancer is associated with changes in the anorectal microbiome during cancer development

Background

Squamous cell carcinoma of the anus (SCCA) is a rare gastrointestinal cancer. Factors associated with progression of HPV infection to anal dysplasia and cancer are unclear and screening guidelines and approaches for anal dysplasia are less clear than for cervical dysplasia. One potential contributing factor is the anorectal microbiome. In this study, we aimed to identify differences in anal microbiome composition in the settings of HPV infection, anal dysplasia, and anal cancer in this rare disease.

Methods

Patients were enrolled in two prospective studies. Patients with anal dysplasia were part of a cross-sectional cohort that enrolled women with high-grade lower genital tract dysplasia. Anorectal tumor swabs were prospectively collected from patients with biopsy-confirmed locally advanced SCCA prior to receiving standard-of-care chemoradiotherapy (CRT). Patients with high-grade lower genital tract dysplasia without anal dysplasia were considered high-risk (HR Normal). 16S V4 rRNA Microbiome sequencing was performed for anal swabs. Alpha and Beta Diversity and composition were compared for HR Normal, anal dysplasia, and anal cancer.

Results

60 patients with high-grade lower genital tract dysplasia were initially enrolled. Seven patients had concurrent anal dysplasia and 44 patients were considered HR Normal. Anorectal swabs from 21 patients with localized SCCA were included, sequenced, and analyzed in the study. Analysis of weighted and unweighted UniFrac distances demonstrated significant differences in microbial community composition between anal cancer and HR normal (p=0.018). LEfSe identified that all three groups exhibited differential enrichment of specific taxa. Peptoniphilus (p=0.028), Fusobacteria (p=0.0295), Porphyromonas (p=0.034), and Prevotella (p=0.029) were enriched in anal cancer specimens when compared to HR normal.

Conclusion

Although alpha diversity was similar between HR Normal, dysplasia and cancer patients, composition differed significantly between the three groups. Increased anorectal Peptoniphilus, Fusobacteria, Porphyromonas, and Prevotella abundance were associated with anal cancer. These organisms have been reported in various gastrointestinal cancers with roles in facilitating the proinflammatory microenvironment and neoplasia progression. Future work should investigate a potential role of microbiome analysis in screening for anal dysplasia and investigation into potential mechanisms of how these microbial imbalances influence the immune system and anal carcinogenesis.

Serial Genotyping of the Human Papillomavirus in Cervical Cancer: An Insight Into Virome Dynamics During Chemoradiation Therapy

PURPOSE

Human papillomavirus (HPV) is the primary driver of cervical cancer. Although studies in other malignancies correlated peripheral blood DNA clearance with favorable outcomes, research on the prognostic value of HPV clearance in gynecologic cancers using intratumoral HPV is scarce. We aimed to quantify the intratumoral HPV virome in patients undergoing chemoradiation therapy (CRT) and associate this with clinical characteristics and outcomes.

METHODS AND MATERIALS

This prospective study enrolled 79 patients with stage IB-IVB cervical cancer undergoing definitive CRT. Cervical tumor swabs collected at baseline and week 5 (end of intensity modulated radiation therapy) were sent for shotgun metagenome sequencing and processed via VirMAP, a viral genome sequencing and identification tool for all known HPV types. The data were categorized into HPV groups (16, 18, high risk [HR], and low risk [LR]). We used independent t tests and Wilcoxon signed-rank to compare continuous variables and χ² and Fisher exact tests to compare categorical variables. Kaplan-Meier survival modeling was performed with log-rank testing. HPV genotyping was verified using quantitative polymerase chain reaction to validate VirMAP results using receiver operating characteristic curve and Cohen's kappa.

RESULTS

At baseline, 42%, 12%, 25%, and 16% of patients were positive for HPV 16, HPV 18, HPV HR, and HPV LR, respectively, and 8% were HPV negative. HPV type was associated with insurance status and CRT response. Patients with HPV 16+ and other HPV HR+ tumors were significantly more likely to have a complete response to CRT versus patients with HPV 18 and HPV LR/HPV-negative tumors. Overall HPV viral loads predominantly decreased throughout CRT, except for HPV LR viral load.

CONCLUSIONS

Rarer, less well-studied HPV types in cervical tumors are clinically significant. HPV 18 and HPV LR/negative tumors are associated with poor CRT response. This feasibility study provides a framework for a larger study of intratumoral HPV profiling to predict outcomes in patients with cervical cancer.

Pathological Effects of Apalutamide in Lower-risk Prostate Cancer: Results From a Phase II Clinical Trial

PURPOSE

Active surveillance is a safe and effective strategy for men with lower-risk prostate cancer who want to avoid local therapy; however, many patients on active surveillance progress to active treatment (eg, prostatectomy or radiation). We hypothesized that apalutamide would decrease active surveillance attrition rates through downstaging low-grade tumors.

MATERIALS AND METHODS

This was an open-label, single-arm, phase II study testing 90 days of oral apalutamide 240 mg daily in men with low- to intermediate-risk prostate cancer on active surveillance. The primary objective was to determine the percentage of patients with a negative biopsy immediately following treatment. Secondary objectives were to assess long-term clinical outcomes, quality of life, safety, and biomarkers of response/resistance.

RESULTS

Twenty-three patients enrolled and 22 completed 90 days of apalutamide with post-treatment biopsy. Fifteen (65%) had Grade Group 1 disease, and all others had Grade Group 2 disease. Seven (30%) had favorable- to intermediate-risk disease. Of 22 evaluable patients, 13 (59%) had no residual cancer on post-treatment biopsy. The median time to first positive biopsy was 364 days (95% CI: 91-742 days). The impact of apalutamide on quality of life was minimal and transient. Decipher risk classifier revealed a greater number of negative post-treatment biopsies in those with higher baseline genomic risk score (P = .01).

CONCLUSIONS

The negative repeat biopsy rate following 90 days of apalutamide was high in men with prostate cancer followed on active surveillance. Apalutamide was safe, well tolerated, and had minimal impact on quality of life. Randomized studies evaluating the effects of apalutamide in men enrolled on active surveillance are warranted.

A Phase 1/2 Study of Rapamycin and Cisplatin/Gemcitabine for Treatment of Patients With Muscle-Invasive Bladder Cancer

INTRODUCTION

Cisplatin-based neoadjuvant chemotherapy (NAC) followed by cystectomy is the standard for muscle-invasive bladder cancer (MIBC), however, NAC confers only a small survival benefit and new strategies are needed to increase its efficacy. Pre-clinical data suggest that in response to DNA damage the tumor microenvironment (TME) adopts a paracrine secretory phenotype dependent on mTOR signaling which may provide an escape mechanism for tumor resistance, thus offering an opportunity to increase NAC effectiveness with mTOR blockade.

PATIENTS & METHODS

We conducted a phase I/II clinical trial to assess the safety and efficacy of gemcitabine-cisplatin-rapamycin combination. Grapefruit juice was administered to enhance rapamycin pharmacokinetics by inhibiting intestinal enzymatic degradation. Phase I was a dose determination/safety study followed by a single arm Phase II study of NAC prior to radical cystectomy evaluating pathologic response with a 26% pCR rate target.

RESULTS

In phase I, 6 patients enrolled, and the phase 2 dose of 35 mg rapamycin established. Fifteen patients enrolled in phase II; 13 were evaluable. Rapamycin was tolerated without serious adverse events. At the preplanned analysis, the complete response rate (23%) did not meet the prespecified level for continuing and the study was stopped due to futility. With immunohistochemistry, successful suppression of the mTOR signaling pathway in the tumor was achieved while limited mTOR activity was seen in the TME.

CONCLUSION

Adding rapamycin to gemcitabine-cisplatin therapy for patients with MIBC was well tolerated but failed to improve therapeutic efficacy despite evidence of mTOR blockade in tumor cells. Further efforts to understand the role of the tumor microenvironment in chemotherapy resistance is needed.

Robotic lateral oropharyngectomy following diagnostic tonsillectomy is oncologically safe in patients with human papillomavirus-related squamous cell cancer: Long-term results

INTRODUCTION

To report the long-term oncological and functional outcomes of en bloc TORS lateral oropharyngectomy to address the close/involved margin following diagnostic tonsillectomy in HPV-related SCC of unknown primary.

MATERIAL AND METHODS

A single tertiary center observational cohort over a 4-year period. Primary outcome measures were disease-specific survival (DSS), overall survival (OS), and PSS NOD (Performance Status Scale-Normalcy of Diet) scores.

RESULTS

TORS specimens did not evidence residual carcinoma in 93% of patients. Of 14 patients, 50% received surgery alone (median follow-up 57 months; range 46-96), the remainder surgery and adjuvant therapy (median follow-up of 58 months; range 51-69) with 100% DSS, OS and no deterioration of PSS NOD scores.

CONCLUSIONS

Long-term oncological outcomes confirm TORS lateral oropharyngectomy alone is an oncologically safe treatment. Due consideration of this approach is warranted to mitigate against the morbidity of adjuvant radiotherapy treatment in this group of patients.

Visible-Light Photoredox-Catalyzed C(sp2)-H Difluoromethoxylation of (Hetero)arenes Utilizing a Shelf-Stable Pyridinium Reagent

Difluoromethoxyarene moieties have been demonstrated to impart desirable physio-chemical properties to organic molecules. Presented herein is a shelf-stable radical difluoromethoxylating reagent that enables facile and direct C(sp²)-H difluoromethoxylation of (hetero)arenes under blue light photoredox catalysis. 4-Cyano-1-(difluoromethoxy)pyridin-1-ium trifluoromethanesulfonate is prepared in one simple step from the parent pyridine N-oxide. The current protocol tolerates a variety of synthetically and pharmacologically relevant functional groups. Applicability toward the late-stage functionalization of APIs and druglike molecules is also demonstrated.

NSABP FC-11: A phase II study of neratinib (N) plus trastuzumab (T) or N plus cetuximab (C) in patients (pts) with "quadruple wild-type" metastatic colorectal cancer (mCRC) based on HER2 status

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Background: Patients (pts) with KRAS wild-type (WT) mCRC treated with single agent anti-EGFR therapy (tx) have improved OS compared to BSC but only a 10-15% response rate. Prior EGFR tx may upregulate HER amplification. For pts with quadruple WT mCRC (KRAS, NRAS, BRAF, PIC3KA), data suggest that dual targeting of the MAPK pathway, specifically EGFR and HER2, may be more effective. The purpose of this study was to evaluate the activity of dual MAPK pathway inhibition based on HER2 status: amplified (amp), non-amplified (non-amp), or mutated (mt). Methods: This 2-arm phase II trial enrolled pts with quad WT mCRC with ECOG PS 0-2, adequate organ function, prior oxaliplatin- and irinotecan-based regimens, and known HER2 status. Arm 1: HER2 amp (confirmed as >2.14 copy number by Guardant 360) and prior anti-EGFR tx or HER2 mt (with qualifying mt) with or without prior anti-EGFR tx; Arm 2: HER2 non-amp or HER2 amp without prior anti-EGFR tx. Tx included T 4 mg/kg IV loading dose → 2 mg/kg/wk and N 240 mg po daily (Arm 1) or C 400 mg/m2 IV loading dose → 250 mg/m2/wk and N 240 mg po daily (Arm 2). Imaging was performed every 8 wks with response per RECIST 1.1. Primary end point (EP) of each arm was 6 mo PFS (PFS6). Secondary EPs: Response rate (ORR), clinical benefit rate (CBR), toxicity and exploratory assessments of N pharmacokinetics, genetic and molecular analyses, and evaluation of multiple drug combinations in PDX/PDXO models. We tested H0: PFS6 <0.13 v HA: PFS6 >0.47 (α=0.05; power=0.90 to reject HA). Treating 15 pts in each arm, if ≥5 pts are alive and progression free (PFS6 0.33), the arm is worth further testing. Results: From Jul 2018 - Mar 2021, 25 pts enrolled from 9 different centers. Arm 1 closed due to poor accrual (n=4). Those pts have been excluded from further analysis. Arm 2 enrolled 21 pts. with 15 evaluable for response by imaging. Early discontinuation occurred in 6 of 21 pts: 2 withdrew consent, 3 due to toxicity, and 1 physician withdrawal. Of the 15 evaluable pts, there were 6 PR, 5 of 13 HER2 non-amp, 1 of 2 HER2 amp, (duration 120-171 days; mean 140) and 5 SD (duration 59-231 days; mean 124). The ORR (CR/PR) in all pts who received at least one dose of tx is 33% (6/20). 8 of 15 evaluable pts (53%) were progression free at cycle 6. Common grade 3+ AEs (>5%) included diarrhea (24%), rash (8%), and abdominal pain/distension (8%), without any grade 5 AEs. Conclusions: The combination of C+N was reasonably well tolerated with expected toxicities of diarrhea and rash. The ORR, CBR, and PFS compare favorably to pts previously relapsed following oxaliplatin and irinotecan and treated with single-agent anti-EGFR tx. Upon entry, biopsies for PDX implantation had an engraftment success rate of ̃80%. We anticipate using these grafts to establish PDXO models for molecular analyses and further drug testing. Support: NSABP Foundation, Puma Biotechnology. Clinical trial information: NCT03457896.

Stromal HIF2 Regulates Immune Suppression in the Pancreatic Cancer Microenvironment

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma (PDAC) has a hypoxic, immunosuppressive stroma that contributes to its resistance to immune checkpoint blockade therapies. The hypoxia-inducible factors (HIFs) mediate the cellular response to hypoxia, but their role within the PDAC tumor microenvironment remains unknown.

METHODS

We used a dual recombinase mouse model to delete Hif1α or Hif2α in α-smooth muscle actin-expressing cancer-associated fibroblasts (CAFs) arising within spontaneous pancreatic tumors. The effects of CAF HIF2α expression on tumor progression and composition of the tumor microenvironment were evaluated by Kaplan-Meier analysis, reverse transcription quantitative real-time polymerase chain reaction, histology, immunostaining, and by both bulk and single-cell RNA sequencing. CAF-macrophage crosstalk was modeled ex vivo using conditioned media from CAFs after treatment with hypoxia and PT2399, an HIF2 inhibitor currently in clinical trials. Syngeneic flank and orthotopic PDAC models were used to assess whether HIF2 inhibition improves response to immune checkpoint blockade.

RESULTS

CAF-specific deletion of Hif2α, but not Hif1α, suppressed PDAC tumor progression and growth, and improved survival of mice by 50% (n = 21-23 mice/group, Log-rank P = .0009). Deletion of CAF-HIF2 modestly reduced tumor fibrosis and significantly decreased the intratumoral recruitment of immunosuppressive M2 macrophages and regulatory T cells. Treatment with the clinical HIF2 inhibitor PT2399 significantly reduced in vitro macrophage chemotaxis and M2 polarization, and improved tumor responses to immunotherapy in both syngeneic PDAC mouse models.

CONCLUSIONS

Together, these data suggest that stromal HIF2 is an essential component of PDAC pathobiology and is a druggable therapeutic target that could relieve tumor microenvironment immunosuppression and enhance immune responses in this disease.

A8 REPEATED SUBMERGENCE OF AIR-LIQUID INTERFACE COLONOID CULTURES IMPAIRS INFLAMMATORY AND REGENERATIVE RESPONSES

Background

Damage in the intestinal epithelium is repaired via de-differentiation of mature intestinal epithelial cells to a stem-like state. Indeed, literature has primarily focused on acute forms of intestinal damage, but there is a lack of models to study how intestinal stem cells function after chronic injury, such as in inflammatory bowel disease (IBD). A previous report found that growth of mouse intestinal organoids in air-liquid interface (ALI) follows by submergence caused differentiation and reversible injury, but this has not been demonstrated in human cells or with repeated cycles of injury. Understanding how chronic damage alters human intestinal stem cell fate and function is imperative to developing novel therapies that repair the epithelium in people with IBD

Aims

To develop a robust in vitro model to differentiate and damage human intestinal epithelial cells, with or without the addition of bacterial flagellin to mimic pathogen exposure.

Methods

Human colonoid monolayers were seeded on Transwell inserts for 10 days until fully confluent and then differentiated by removing the apical media to create ALI growth conditions for 7 days. To induce damage, media was added to the apical side of the Transwell, with or without the addition of flagellin in the basolateral compartment. Following submergence induced damage, the apical media was removed and collected for chemokine analysis, and the cells were grown back in ALI for 3 days to recover them from injury. This cycle was repeated 5 times to induce chronic damage. Cells were collected for qPCR analysis, immunofluorescence imaging, RNA sequencing and DNA methylation analysis

Results

Repeated rounds of damage impaired the ability of intestinal epithelial cells (IECs) to respond to TLR stimulation (a decrease in basolateral IL-8 with each round), likely due to a decrease in TLR signaling pathways, as demonstrated by GSEA and qPCR. Chronic submergence damage led to an increase in differentiation of cells expressing MUC2, SLC26a3 and CHGA, and a decrease in stemness as shown by qPCR for BMI1, HOPX, and LGR5. After several rounds of damage, colonoid monolayers were unable to regrow as monolayers after passaging, likely due to a decrease in YAP signaling. We also identified mRNA expression and DNA methylation changes in genes associated with IBD and colon cancer.

Conclusions

We have developed a novel chronic damage model of recurrent IEC injury, which possibly mimics pathologies seen in people with inflammatory bowel disease. This model can be used to understand how chronic damage alters the ability of IECs to respond to pathogens and regenerate to repair and protect the epithelium from further damage.

Funding Agencies

CCC

Expansion of Candidate HPV-Specific T Cells in the Tumor Microenvironment during Chemoradiotherapy Is Prognostic in HPV16+ Cancers

Human papillomavirus (HPV) infection causes 600,000 new cancers worldwide each year. HPV-related cancers express the oncogenic proteins E6 and E7, which could serve as tumor-specific antigens. It is not known whether immunity to E6 and E7 evolves during chemoradiotherapy or affects survival. Using T cells from 2 HPV16⁺ patients, we conducted functional T-cell assays to identify candidate HPV-specific T cells and common T-cell receptor motifs, which we then analyzed across 86 patients with HPV-related cancers. The HPV-specific clones and E7-related T-cell receptor motifs expanded in the tumor microenvironment over the course of treatment, whereas non-HPV-specific T cells did not. In HPV16⁺ patients, improved recurrence-free survival was associated with HPV-responsive T-cell expansion during chemoradiotherapy.

A quality-adjusted time without symptoms or toxicity (Q-TWiST) analysis of patients in CheckMate 649: Nivolumab plus chemotherapy versus chemotherapy as first-line treatment for advanced gastric cancer/gastroesophageal junction cancer/esophageal adenocarcinoma (GC/GEJC/EAC)

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Background: In CheckMate 649 (CM 649), a randomized phase 3 trial of first-line treatment of advanced GC/GEJC/EAC, patients receiving nivolumab combined with chemotherapy (NIVO plus chemo) experienced superior overall survival (OS), progression-free survival (PFS), and maintained their HRQOL for longer duration versus chemo alone. In this analysis, we combined efficacy and HRQOL data from CM-649 into a single metric, quality-adjusted time without symptoms of disease progression or toxicity (Q-TWiST), to compare the net benefits of NIVO plus chemo versus chemo alone. Methods: In this analysis, OS was partitioned into three health states: time with grade 3/4 toxicity after randomization and before progression (TOX), time without symptoms of disease progression or toxicity (TWiST), and time from relapse or progression until death (ie, relapse, REL). Mean Q-TWiST was determined by multiplying each state’s duration with its utility (U) (U[TWiST], 1.0; U[TOX], 0.5; U[REL], 0.5). Relative Q-TWiST gains (calculated as Q-TWiST difference divided by chemo only OS) of ≥ 10% and ≥ 15% were defined as clinically important and clearly clinically important, respectively, based on established thresholds for clinical importance in prior Q-TWiST literature. Q-TWiST differences between treatments were calculated separately for patients whose tumors expressed PD-L1 CPS ≥ 5 and for all randomized. A threshold utility analysis assessed Q-TWiST differences by varying the TOX and REL utility between 0 and 1. Results: Compared with chemo alone, treatment with NIVO plus chemo was associated with Q-TWiST improvement of 2.8 months (95% CI 1.0-3.7; relative gain 20.6% [clearly clinically important]) in patients with PD-L1 CPS ≥ 5, and 1.8 months (95% CI 0.9-2.7; relative gain 12.7% [clinically important]) in all randomized patients, respectively. Threshold analyses showed that compared with chemo alone, treatment with NIVO plus chemo was associated with statistically significant Q-TWiST improvements exceeding minimum clinically important differences across the full range of TOX and REL utility values. Conclusions: Among previously untreated patients with GC/GEJC/EAC in CM-649, NIVO plus chemo significantly improved quality-adjusted survival compared with chemo alone. Q-TWiST gains with NIVO plus chemo were driven mostly by longer time patients experienced without symptoms of disease progression or toxicity (TWiST), and were associated with statistically significant and clinically meaningful gains. These Q-TWiST results provide further understanding of both a survival and quality of life benefit of NIVO plus chemo versus chemo alone, and may aid clinicians and patients in management decisions for this patient population.

Impact of race/ethnicity and socioeconomic status on emergency department visits in patients with hepatocellular carcinoma

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Background: Despite advances in diagnosis and treatment of hepatocellular carcinoma (HCC), disparities in care utilization and health outcomes persist. Few studies have evaluated the impact of race/ethnicity and socioeconomic status (SES) on incidence of emergency department (ED) visits, which may reflect access to and quality of cancer care. We investigated this relationship among patients (pts) with HCC. Methods: Using 100% Medicare Fee-for-Service claims and a commercial multi-payor claims database, pts diagnosed with HCC between 2014-2018 were identified. Using 9-digit ZIP code from enrollment records, pts were matched to near-neighborhood social determinants of health (SDOH) characteristics, including income, education, English language ability, living alone, vehicle ownership, rurality, and primary care shortages. We defined SES according to income level: low (≤2 times [x] federal poverty level [FPL]), middle (2-3x FPL), and high (>3x FPL). We used generalized linear regressions to evaluate the effect of race/ethnicity on incidence rate ratios (IRR) of ED visits, adjusting for SDOH variables and demographic and clinical characteristics. We further stratified ED IRR by income level to examine how racial/ethnic differences in ED visits differ by SES. Results: 22,247 pts with HCC were identified (median age 69; 63% male; 69% White, 14% Black, 7% Hispanic, 6% Asian, 4% Other). The table summarizes adjusted IRR of ED visits for each racial/ethnic group compared with whites, overall and by income level. Overall, ED visits were higher for Blacks (IRR 1.27) and Hispanics (IRR 1.17) and lower for Asians (IRR 0.67). When stratified by income, Blacks and Hispanics had larger incidence of ED visits compared with Whites at higher income levels; these differences became insignificant at low income level. Asians had lower rate of ED visits regardless of income. Conclusions: Black and Hispanic pts with HCC demonstrated higher rates of ED visits compared with Whites. These differences were more pronounced at higher income levels, particularly for Blacks, suggesting racial disparities may differ by SES. Further research is needed to understand the intersectionality between race/ethnicity, SES and other SDOH, to guide structural-level interventions to address these disparities. [Table: see text]

Visualization of Fast Ion Phase-Space Flow Driven by Alfvén Instabilities

Fast ion phase-space flow, driven by Alfvén eigenmodes (AEs), is measured by an imaging neutral particle analyzer in the DIII-D tokamak. The flow firstly appears near the minimum safety factor at the injection energy of neutral beams, and then moves radially inward and outward by gaining and losing energy, respectively. The flow trajectories in phase space align well with the intersection lines of the constant magnetic moment surfaces and constant E-(ω/n)P_{ζ} surfaces, where E, P_{ζ} are the energy and canonical toroidal momentum of ions; ω and n are angular frequencies and toroidal mode numbers of AEs. It is found that the flow is so destructive that the thermalization of fast ions is no longer observed in regions of strong interaction. The measured phase-space flow is consistent with nonlinear hybrid kinetic-magnetohydrodynamics simulation. Calculations of the relatively narrow phase-space islands reveal that fast ions must transition between different flow trajectories to experience large-scale phase-space transport.

Elucidation of Tumor-Stromal Heterogeneity and the Ligand-Receptor Interactome by Single-Cell Transcriptomics in Real-world Pancreatic Cancer Biopsies

PURPOSE

Precision medicine approaches in pancreatic ductal adenocarcinoma (PDAC) are imperative for improving disease outcomes. With molecular subtypes of PDAC gaining relevance in the context of therapeutic stratification, the ability to characterize heterogeneity of cancer-specific gene expression patterns is of great interest. In addition, understanding patterns of immune evasion within PDAC is of importance as novel immunotherapeutic strategies are developed.

EXPERIMENTAL DESIGN

Single-cell RNA sequencing (scRNA-seq) is readily applicable to limited biopsies from human primary and metastatic PDAC and identifies most cancers as being an admixture of previously described epithelial transcriptomic subtypes.

RESULTS

Integrative analyses of our data provide an in-depth characterization of the heterogeneity within the tumor microenvironment, including cancer-associated fibroblast subclasses, and predicts for a multitude of ligand-receptor interactions, revealing potential targets for immunotherapy approaches.

CONCLUSIONS

Our analysis demonstrates that the use of de novo biopsies from patients with PDAC paired with scRNA-seq may facilitate therapeutic prediction from limited biopsy samples.