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Five-year survival for human papilloma virus-unrelated head and neck squamous cell carcinomas remain below 50%. We assessed the safety of administering combination hypofractionated stereotactic body radiation therapy with single-dose durvalumab (anti-PD-L1) neoadjuvantly (n = 21) (NCT03635164). The primary endpoint of the study was safety, which was met. Secondary endpoints included radiographic, pathologic and objective response; locoregional control; progression-free survival; and overall survival. Among evaluable patients at an early median follow-up of 16 months (448 d or 64 weeks), overall survival was 80.1% with 95% confidence interval (95% CI) (62.0%, 100.0%), locoregional control and progression-free survival were 75.8% with 95% CI (57.5%, 99.8%), and major pathological response or complete response was 75% with 95% exact CI (51.6%, 100.0%). For patients treated with 24 Gy, 89% with 95% CI (57.1%, 100.0%) had MPR or CR. Using high-dimensional multi-omics and spatial data as well as biological correlatives, we show that responders had: (1) an increase in effector T cells; (2) a decrease in immunosuppressive cells; and (3) an increase in antigen presentation post-treatment.

Purpose:Patients with human EGFR2-positive (HER2+) breast cancer have a high incidence of brain metastases, and trastuzumab emtansine (T-DM1) is often employed. Stereotactic radiosurgery (SRS) is frequently utilized, and case series report increased toxicity with combination SRS and T-DM1. We provide an update of our experience of T-DM1 and SRS evaluating risk of clinically significant radionecrosis (CSRN) and propose a mechanism for this toxicity.Experimental Design:Patients with breast cancer who were ≤45 years regardless of HER2 status or had HER2+ disease regardless of age and underwent SRS for brain metastases were included. Rates of CSRN, SRS data, and details of T-DM1 administration were recorded. Proliferation and astrocytic swelling studies were performed to elucidate mechanisms of toxicity.Results:A total of 45 patients were identified; 66.7% were HER2+, and 60.0% were ≤ 45 years old. Of the entire cohort, 10 patients (22.2%) developed CSRN, 9 of whom received T-DM1. CSRN was observed in 39.1% of patients who received T-DM1 versus 4.5% of patients who did not. Receipt of T-DM1 was associated with a 13.5-fold (P = 0.02) increase in CSRN. Mechanistically, T-DM1 targeted reactive astrocytes and increased radiation-induced cytotoxicity and astrocytic swelling via upregulation of Aquaporin-4 (Aqp4).Conclusions:The strong correlation between development of CSRN after SRS and T-DM1 warrants prospective studies controlling for variations in timing of T-DM1 and radiation dosing to further stratify risk of CSRN and mitigate toxicity. Until such studies are completed, we advise caution in the combination of SRS and T-DM1.

Chemotherapy effects on astrocytes

Despite recently approved immunotherapy combinations, Hepatocellular carcinoma (HCC) remains among the most therapeutically intractable cancers with a 5-year survival rate of only 18%. Underlying chronic liver disease due to hepatitis B/C infection, alcohol abuse, hemochromatosis, or nonalcoholic steatohepatitis promotes HCC development. Current therapeutic strategies include surgery, radiotherapy and multikinase inhibitors alone or with immune-checkpoint blockade (ICB). In particular, the receptor tyrosine kinase MET and its ligand hepatocyte growth factor (HGF) are known drivers of HCC through promotion of tumor growth, survival, tissue invasion, and angiogenesis. Previously, our collaborators showed that the limited clinical benefit of MET kinase inhibition was partially a result of induced upregulation PD-L1 leading to local T cell suppression. We hypothesized that combining MET inhibition with blockade of the PD-1 immune checkpoint would overcome the limitations of each individual approach and act synergistically to promote HCC tumor regression. We first validated that both MET selective (Capmatinib and Tivantinib) and non-selective (Cabozantinib) inhibitors all induced PD-L1 on HCC cell lines in vitro. Next, we compared Capmatinib and Cabozantinib alone and with PD-1 ICB in vivo in the ICB-sensitive Hepa1-6 and HCA-1 models of HCC. In HCA-1, statistically significant benefit of the MET inhibitor and αPD-1 combination was evident in limitation of tumor growth and extension of survival. In each case, the Capmatinib combination trended toward better outcomes with PD-1 blockade. Mechanistically, the Capmatinib and αPD-1 combination decreased tumor Treg cells while promoting increased accumulation of activated, non-exhausted, proliferating CD8 T cells. Central memory CD8 T cell frequencies were increased by the combination during the effector phase, and combination treated animals were better protected against subsequent rechallenge than those cured by αPD-1 alone. In the myeloid compartment, M1 macrophage frequencies were increased while PMN-MDSC both decreased in frequency and in Arginase 1 levels. Finally, we studied a serially-passaged, αPD-1 refractory DEN HCC model. Despite lack of efficacy of either component therapy, the MET inhibitor and αPD-1 combination significantly extended survival and inhibited tumor growth. As in the αPD-1 sensitive setting, Capmatinib appeared to offer the most therapeutic benefit with αPD-1. Ongoing studies are focused on characterizing changes mediated by the combination therapy which confer aPD-1 sensitivity to the otherwise refractory DEN HCC tumor microenvironment. Molecular studies are focused on understanding the superior ICB potentiating capacity of Type I MET inhibitors versus the other classes. Given the clinical availability of numerous MET and PDL-1 inhibitors, we hope to inform near-term optimization of MET and αPD-1 clinical trial design for HCC. Citation Format: Ricardo A. de Azevedo, Broderick Turner, Priyamvada Jayaprakash, Krithikaa Rajkumar Bhanu, Anupallavi Srinivasamani, Brittany Morrow, Michelle Winkler, Shweta Mahendra Hedge, Arthur Liu, Ravaen Slay, Michael A. Curran. Proposing the best MET inhibitor to improve anti-PD-1 efficacy in HCC. [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 5745.

Radiotherapy (RT) of colorectal cancer (CRC) can prime adaptive immunity against tumor-associated antigen (TAA)–expressing CRC cells systemically. However, abscopal tumor remissions are extremely rare, and the postirradiation immune escape mechanisms in CRC remain elusive. Here, we found that irradiated CRC cells used ATR-mediated DNA repair signaling pathway to up-regulate both CD47 and PD-L1, which through engagement of SIRPα and PD-1, respectively, prevented phagocytosis by antigen-presenting cells and thereby limited TAA cross-presentation and innate immune activation. This postirradiation CD47 and PD-L1 up-regulation was observed across various human solid tumor cells. Concordantly, rectal cancer patients with poor responses to neoadjuvant RT exhibited significantly elevated postirradiation CD47 levels. The combination of RT, anti-SIRPα, and anti–PD-1 reversed adaptive immune resistance and drove efficient TAA cross-presentation, resulting in robust TAA-specific CD8 T cell priming, functional activation of T effectors, and increased T cell clonality and clonal diversity. We observed significantly higher complete response rates to RT/anti-SIRPα/anti–PD-1 in both irradiated and abscopal tumors and prolonged survival in three distinct murine CRC models, including a cecal orthotopic model. The efficacy of triple combination therapy was STING dependent as knockout animals lost most benefit of adding anti-SIRPα and anti–PD-1 to RT. Despite activation across the myeloid stroma, the enhanced dendritic cell function accounts for most improvements in CD8 T cell priming. These data suggest ATR-mediated CD47 and PD-L1 up-regulation as a key mechanism restraining radiation-induced immune priming. RT combined with SIRPα and PD-1 blockade promotes robust antitumor immune priming, leading to systemic tumor regressions.

Advances in our understanding of tumor immune biology and development of cancer immunotherapies have led to improved outcomes for patients that suffer from aggressive cancers such as metastatic melanoma. Despite these advances, a significant proportion of patients still fail to benefit, and as a result, attention has shifted to understanding how cancer cells escape immune destruction. Of particular interest is the metabolic landscape of the tumor microenvironment, as recent studies have demonstrated how both competition for essential nutrients and depletion of specific amino acids can promote T cell dysfunction. Here, we will discuss the major energetic pathways engaged by both T cells and cancer cells, metabolic substrates present in the tumor microenvironment, and emerging therapeutic strategies that seek to improve T cell metabolic fitness and bolster the antitumor immune response.

Survival outcomes for older adults with acute lymphoblastic leukemia (ALL) are poor and optimal management is challenging due to higher-risk leukemia genetics, comorbidities, and lower tolerance to intensive therapy. A critical understanding of these factors guides the selection of frontline therapies and subsequent treatment strategies. In addition, there have been recent developments in minimal/measurable residual disease (MRD) testing and blinatumomab use in the context of MRD-positive disease after therapy. These NCCN Guidelines Insights discuss recent updates to the NCCN Guidelines for ALL regarding upfront therapy in older adults and MRD monitoring/testing in response to ALL treatment.

The recent rise in online education and the accompanying difficulties encountered by both students and educators demonstrate the value of better understanding how online environments can facilitate learning and community. Fanfiction websites contain an enormous amount of original creative writing, primarily written by young people, offering an opportunity to examine informal learning within an online community. Previous research has shown that fanfiction encourages this informal learning through “distributed mentoring,” which occurs when members of an online community quickly and asynchronously receive abundant feedback, while giving others feedback in turn [1]. However, not all interaction in online communities has such a positive nature, as a study of massive open online courses found students who received longer feedback became less likely to reciprocate with similar effort when leaving peer reviews [4]. This study looked at reciprocity between fanfiction reviewers and found a moderate, statistically significant correlation between the quality of reviews given and received by fanfiction authors. These findings are valuable in understanding the ways in which members of online communities interact and learn from each other, an area that would benefit from further research.

PURPOSE: The role of peri-transplant radiation therapy (RT) in young children with primary brain tumors is unclear. We characterized our institutional practice patterns and patient outcomes. MATERIALS AND METHODS: The cohort included all patients treated with high-dose chemotherapy for primary brain tumors at our institution from 2011-2017. Rates of local control (LC), progression-free survival (PFS), overall survival (OS), and radiation-associated injury were assessed. RESULTS: Of 37 eligible patients, 29 (78%) received peri-transplant RT at a median age of 4 years. Patients treated with RT were more likely to have metastatic (p=0.0121) and incompletely resected (p=0.056) disease, and to have high-risk histologies including atypical teratoid rhabdoid tumor, nongerminomatous germ cell tumor, pineoblastoma, primitive neuro-ectodermal tumor, glioneuronal tumor and group 3 medulloblastoma. Of those treated with RT, 13 (45%) received craniospinal irradiation (CSI) and 16 (55%) received focal RT. The median CSI dose was 23.4 Gy (IQR: 18-36; boost median 54 Gy [IQR: 53.7-55.8]) and focal RT dose was 50.4 Gy (IQR: 50.4-54.5). Compared to the focal RT group, patients treated with CSI were older (p=0.0499) and more likely to have metastatic disease (p=0.0004). For the complete cohort, at a median follow-up of 3.8 years, the 2-year rate of LC was 82% (95% CI: 70-96%), PFS was 63% (95% CI: 49-81%), and OS was 65% (95% CI: 51-82%). These rates did not differ significantly between patients treated with and without peri-transplant RT. Two cases of fatal myelopathy were observed after spinal cord doses within the highest tertile (41.4 CGE and 36 Gy); both cases occurred in patients who received RT before high-dose chemotherapy. CONCLUSION: Peri-transplant RT was used for high-risk disease. Oncologic outcomes after RT were encouraging. However, 2 cases of grade 5 myelopathy were observed. If used cautiously, RT may contribute to durable remission in patients at high risk of relapse.

Despite the clinical success of T-cell checkpoint blockade, most patients with cancer still fail to have durable responses to immunotherapy. The molecular mechanisms driving checkpoint blockade resistance, whether preexisting or evolved, remain unclear. To address this critical knowledge gap, we treated B16 melanoma with the combination of CTLA-4, PD-1, and PD-L1 blockade and a Flt3 ligand vaccine (≥75% curative), isolated tumors resistant to therapy, and serially passaged them in vivo with the same treatment regimen until they developed complete resistance. Using gene expression analysis and immunogenomics, we determined the adaptations associated with this resistance phenotype. Checkpoint resistance coincided with acquisition of a “hypermetabolic” phenotype characterized by coordinated upregulation of the glycolytic, oxidoreductase, and mitochondrial oxidative phosphorylation pathways. These resistant tumors flourished under hypoxic conditions, whereas metabolically starved T cells lost glycolytic potential, effector function, and the ability to expand in response to immunotherapy. Furthermore, we found that checkpoint-resistant versus -sensitive tumors could be separated by noninvasive MRI imaging based solely on their metabolic state. In a cohort of patients with melanoma resistant to both CTLA-4 and PD-1 blockade, we observed upregulation of pathways indicative of a similar hypermetabolic state. Together, these data indicated that melanoma can evade T-cell checkpoint blockade immunotherapy by adapting a hypermetabolic phenotype.

Our voices can convey many different types of thoughts and intent; how our voices carry them is often not consciously controlled and as a consequence, unintended effects may arise that negatively impact our relationships. How we say things is as important as what we say. This paper presents methodologies for computing a set of physical properties from sound waves of a speaker's voice directly, referred to as acoustic measures. Experiments are designed and conducted to establish the correlations between physical properties and auditory measures for human perception of sound waves. Based on these correlations, a voice coaching app can guide users, in real-time or deferred retrospective, to modify their speech's auditory measures, such as rate of speech, energy level, and intonation, to achieve their intended communication goals.

Background: As the large number of Community Health Service (CHS) centers in China face the majority of non-valvular atrial fibrillation (NVAF) patients, primary care physicians (PCPs) play the primary role in the prevention of embolization. Therefore，an awareness of anticoagulant management in NVAF patients must be brought into focus among PCPs in China. This study will investigate PCPs’ Knowledge, Attitude and Practice toward anticoagulant therapy in patients with NVAF and help PCPs increase their awareness of oral anticoagulant (OAC) therapy for NVAF to prevent embolization. Method: This was a cross-sectional observational study of 462 PCPs in CHS centers across Shanghai. We used a self-administered questionnaire to collect data from September to December 2017. A stratified random cluster sampling was adopted in the 90 CHS centers with the family medicine residency program. Result: Among 462 participants, 69.3% (320/462) of females got a medical bachelor’s degree and over 50% participants had more than 10 years of work experience. According to similar study, each section for knowledge, attitude, and practice were categorized as poor (≤39.0%), fair (40.0%–69.0%), and good (≥70.0%) [18] . The level of knowledge of OAC therapy in patients with NVAF among PCPs was insufficient in over half (75.8%) of participants. The majority (89.8%) of PCPs had a positive attitude and 68.0% had modest performance in the anticoagulant management of patients with NVAF. Conclusion: The knowledge and behaviors of PCPs were insufficient in OAC therapy to prevent embolization in patients with NVAF. The study also revealed there is good potential for PCPs’ educational interventions to positively impact on the care of patients with NVAF.

BackgroundAs a large number of Community Health Service (CHS) centers in China face the majority of patients with non-valvular atrial fibrillation (NVAF), primary care physicians (PCPs) play a primary role in the prevention of embolization. Therefore, an awareness of anticoagulant management in patients with NVAF must be brought into focus among PCPs in China. This study investigated PCPs’ knowledge, attitudes, and practices toward anticoagulant therapy in patients with NVAF, to help them understand their shortcomings regarding oral anticoagulant (OAC) therapy in preventing embolization.MethodThis was a cross-sectional observational study of 462 PCPs in CHS centers across Shanghai. We used a self-administered questionnaire to collect data from September to December 2017. A stratified random cluster sampling was adopted in the 90 CHS centers with the family medicine residency program.ResultAmong 462 participants, 69.3% (320/462) of females received a medical bachelor’s degree and over 50% of participants had more than 10 years of work experience. Each section for knowledge, attitude, and practice were categorized as poor (≤39.0%), fair (40.0–69.0%), and good (≥70.0%). The level of knowledge of OAC therapy for patients with NVAF among PCPs was insufficient in over half (75.8%) of the participants. The majority (89.8%) of PCPs had a positive attitude and 68.0% had modest performance in the anticoagulant management of patients with NVAF.ConclusionsThe knowledge and behaviors of PCPs were insufficient for OAC therapy to prevent embolization in patients with NVAF. The study also revealed that there is good potential for PCPs’ educational interventions to positively impact the care of patients with NVAF.

Radiation-induced high-grade gliomas (RIGs) are an incurable late complication of cranial radiation therapy. We performed DNA methylation profiling, RNA-seq, and DNA sequencing on 32 RIG tumors and an in vitro drug screen in two RIG cell lines. We report that based on DNA methylation, RIGs cluster primarily with the pediatric receptor tyrosine kinase I high-grade glioma subtype. Common copy-number alterations include Chromosome (Ch.) 1p loss/1q gain, and Ch. 13q and Ch. 14q loss; focal alterations include PDGFRA and CDK4 gain and CDKN2A and BCOR loss. Transcriptomically, RIGs comprise a stem-like subgroup with lesser mutation burden and Ch. 1p loss and a pro-inflammatory subgroup with greater mutation burden and depleted DNA repair gene expression. Chromothripsis in several RIG samples is associated with extrachromosomal circular DNA-mediated amplification of PDGFRA and CDK4. Drug screening suggests microtubule inhibitors/stabilizers, DNA-damaging agents, MEK inhibition, and, in the inflammatory subgroup, proteasome inhibitors, as potentially effective therapies., Radiation-induced high-grade gliomas (RIGs) are an incurable late complication of cranial radiation therapy. In the largest study to date, we report the results of DNA methylation profiling, RNA-Seq and genomic sequencing of 32 RIG tumors, and an in vitro drug screen in two RIG cell lines.

Immune checkpoint blockade (ICB) has demonstrated an impressive outcome in patients with metastatic melanoma, yet, durable complete response; even with Ipilimumab/Nivolumab combo are under 30%. Primary and acquired resistance in response to ICB is commonly due to a tumor immune escape mechanism dictated by the tumor microenvironment (TME). Macrophage Migratory Inhibition Factor (MIF) has emerged as an immunosuppressive factor secreted in the TME. We have previously demonstrated that blockade of the MIF-CD74 signaling on macrophages and dendritic cells restored the anti-tumor immune response against melanoma. Here, we report that inhibition of the MIF-CD74 axis combined with ipilimumab could render resistant melanoma to better respond to anti-CTLA-4 treatment. We provide evidence that blocking the MIF-CD74 signaling potentiates CD8+ T-cells infiltration and drives pro-inflammatory M1 conversion of macrophages in the TME. Furthermore, MIF inhibition resulted in reprogramming the metabolic pathway by reducing lactate production, HIF-1α and PD-L1 expression in the resistant melanoma cells. Melanoma patient data extracted from the TCGA database supports the hypothesis that high MIF expression strongly correlates with poor response to ICB therapy. Our findings provide a rationale for combining anti-CTLA-4 with MIF inhibitors as a potential strategy to overcome resistance to ICB therapy in melanoma, turning a “cold” tumor into a “hot” one mediated by the activation of innate immunity and reprogramming of tumor metabolism and reduced PD-L1 expression in melanoma cells.

In Hong Kong, over 2.4% of the total population suffered from visual impairment. They are facing many difficulties in their daily lives, such as shopping and travelling from places to places within the city. For outdoor activities, they usually need to have an assistant to guide their ways to reach the destinations. In this paper, a mobile application assisting visually impaired people for outdoor navigation is proposed. The application consists of navigation, obstacle detection and scene description functions. The navigation function assists the user to travel to the destination with the Global Positioning System (GPS) and sound guidance. The obstacle detection function alerts the visually impaired people for any obstacles ahead that may be avoided for collision. The scene description function describes the scene in front of the users with voice. In general, the mobile application can assist the people with low vision to walk on the streets safely, reliably and efficiently.

Despite the success of immune checkpoint blockade against melanoma, many "cold" tumors like prostate cancer remain unresponsive. We found that hypoxic zones were prevalent across preclinical prostate cancer and resisted T cell infiltration even in the context of CTLA-4 and PD-1 blockade. We demonstrated that the hypoxia-activated prodrug TH-302 reduces or eliminates hypoxia in these tumors. Combination therapy with this hypoxia-prodrug and checkpoint blockade cooperated to cure more than 80% of tumors in the transgenic adenocarcinoma of the mouse prostate-derived (TRAMP-derived) TRAMP-C2 model. Immunofluorescence imaging showed that TH-302 drives an influx of T cells into hypoxic zones, which were expanded by checkpoint blockade. Further, combination therapy reduced myeloid-derived suppressor cell density by more than 50%, and durably reduced the capacity of the tumor to replenish the granulocytic subset. Spontaneous prostate tumors in TRAMP transgenic mice, which completely resist checkpoint blockade, showed minimal adenocarcinoma tumor burden at 36 weeks of age and no evidence of neuroendocrine tumors with combination therapy. Survival of Pb-Cre4, Ptenpc-/-Smad4pc-/- mice with aggressive prostate adenocarcinoma was also significantly extended by this combination of hypoxia-prodrug and checkpoint blockade. Hypoxia disruption and T cell checkpoint blockade may sensitize some of the most therapeutically resistant cancers to immunotherapy.

BackgroundBackground: Radiotherapy of colorectal cancer (CRC) can prime adaptive immunity against tumor-associated antigen (TAA)-expressing CRC cells systemically; however, incidences of abscopal tumor remission are extremely rare. We sought to unravel the post-irradiation immune escape mechanisms in CRC.MethodsMethodsFlow cytometry, gene knockdown, RNA and T cell receptor sequencing, and multiple murine syngeneic CRC models were used to interrogate mechanisms of CRC immune evasion following radiotherapy. Comparison of immunohistochemistry staining between pretreatment biopsy and post-irradiation surgical specimens was performed in rectal patients who underwent neoadjuvant radiotherapy with 5 Gy for 5 fractions.ResultsResultsWe find that CRC cells utilize a common DNA repair signaling pathway — ATR/Chk1/STAT3 — to upregulate both CD47 and PD-L1 in response to radiotherapy, which through engagement of SIRPα and PD-1 suppresses the capacity of antigen-presenting cells (APCs) to phagocytose them thereby preventing TAA cross-presentation. This post-irradiation CD47 and PD-L1 upregulation can be observed in CRC cells treated with either photon or proton radiotherapy and across a wide variety of human solid tumor cells. Concordantly, rectal cancer patients who responded poorly (tumor regression grade 4–5, n = 10) to neoadjuvant radiotherapy exhibited significantly elevated post-irradiation CD47 levels (P = 0.005). In murine CRC models, the combination of radiotherapy, αSIRPα, and αPD-1 (RSP) profoundly enhances TAA uptake, activation of innate immune sensors, and TAA cross-priming across various antigen-presenting myeloid populations in the irradiated tumor microenvironment and facilitates TAA-presenting APC migration to secondary lymphoid organs. Furthermore, we observed robust production of TAA-specific CD8 T cells, functional activation of effector T cells, and increased tumor-infiltrating T cell clonality and clonal diversity in mice treated with RSP. Importantly, radiotherapy coupled with phagocytosis checkpoint blockade significantly improves complete response rates in both irradiated and abscopal tumors and prolongs survival in three distinct murine CRC models, including a cecal orthotopic model. In addition, αSIRPα exerts superior tumoricidal efficacy than αCD47 in combination with RT and αPD-1. We find RSP efficacy to be STING dependent as knockout animals lose most benefit of phagocytosis checkpoint blockade.ConclusionATR-mediated CD47 and PD-L1 upregulation restrains radiation-induced immune priming in CRC. Blockade of the phagocytosis checkpoints SIRPα and PD-1 during radiotherapy promotes vigorous anti-CRC immune priming leading to systemic tumor regression.AcknowledgementsThis study is supported in part by NIH grant P30 CA16672, the MD Anderson Andrew Sabin Family Fellowship, and Chang Gung Memorial Hospital grant CMRPG3K1751. RCH was supported by the CPRIT Research Training Grant (RP170067) and Ralph B. Arlinghaus Ph.D. Scholarship. The authors are grateful to the members of the Advanced Cytometry & Sorting Facility at South Campus, Tissue Bank of Chang Gung Memorial Hospital at Linkou, and MHC Tetramer Core Facility at Baylor College of Medicine for their invaluable help.Ethics ApprovalThis study was approved by the Institutional Review Board of Chang Gung Memorial Hospital, Taiwan; approval number: 202001191B0C601.

Treatment-induced high-grade gliomas (TIHGGs) are an incurable late complication of cranial radiation therapy or combined radiation/chemotherapy used to treat pediatric cancer. We assembled a cohort of 33 TIHGGs from multiple institutions. The primary antecedent malignancies were medulloblastoma, acute lymphoblastic leukemia, astrocytoma, and ependymoma. We performed methylation profiling, RNA-seq, and genomic sequencing (whole-genome or whole-exome) on TIHGG samples. Methylation profiling revealed that TIHGGs cluster primarily with the pediatric receptor tyrosine kinase I subtype (26/31 samples). Common TIHGG copy-number alterations include Chromosome (Ch.) 1p loss/1q gain, Ch. 4 loss, Ch. 6q loss, and Ch. 13 and Ch. 14 loss; focal alterations include PDGFRA and CDK4 gain and loss of CDKN2A and BCOR. Relative to de novo pediatric high-grade glioma (pHGG), BCOR loss (p=0.004) and CDKN2A loss (p=0.005) were significantly increased. Transcriptomic analysis identified two distinct TIHGG subgroups, one with a lesser mutation burden (0.12 mut/Mb), Ch. 1p loss/1q gain (5/6 samples), and stem cell characteristics, and one with a greater mutation burden (1.08 mut/Mb, pPDGFRA and CDK4. In vitro drug screening in one primary, patient-derived TIHGG cell line from each expression subgroup identified microtubule inhibitors/stabilizers, DNA-damaging agents, MEK inhibition, and, in the inflammatory subgroup, proteasome inhibitors as potentially effective therapies. This study provides a comprehensive molecular profile of TIHGG, including mechanistic insights to TIHGG oncogenesis, and identifies potentially effective therapeutic modalities for further investigation.

Cognitive late effects of brain tumors and related treatments are well-established; however, limited information regarding changes in cognition during radiation therapy (RT) is available. Recent advances in computerized neuropsychological assessments for monitoring of acute and late treatment effects have been developed, though the feasibility of using these tools in a population undergoing active RT has limited empirical evidence. This study investigated performance of pediatric patients with brain tumors actively undergoing RT on the NIH Toolbox (N = 10; M age = 11.29 ± 3.35 years; 86% Caucasian; 86% female). Given significant individual variability, one-sample proportion tests were calculated to assess whether the proportion of patients with performances >1 standard deviation below the mean significantly differed from normative expectations. Of the 12 participants that were enrolled in the study, 10 completed the NIH Toolbox during active RT. Compared to normative expectations, a greater proportion of participants undergoing active RT exhibited deficits on measures of processing speed, working memory, and response inhibition (p=.05). Seventy-seven percent of recruited participants completed computerized assessment during active RT, suggesting reasonable feasibility within the small cohort recruited. Consistent with the literature regarding late effects of RT, performance on computerized measures of cognitive functioning mediated by processing speed and aspects of executive functioning were lower for patients undergoing active RT. Further investigation will focus on clarifying the trajectory of deficits across treatment course and comparing computerized measures to traditional neuropsychological measures.

Advances in our understanding of tumor immune biology and development of cancer immunotherapies have led to improved outcomes for patients who suffer from aggressive cancers such as melanoma. Despite the clinical success of immune checkpoint blockade, a majority of patients still fail to respond, and the underlying mechanisms that drive resistance remain unclear. To understand why a subset of tumors fail to respond to immunotherapy, we established a novel murine model of melanoma that is fully resistant to immune checkpoint blockade. By in vivo passaging nonresponding B16 melanoma tumor cells, we selected for a resistant variant that fails to respond to the combination of CTLA-4, PD-1, and PD-L1 blockade. In comparing gene expression of parental versus resistant tumor cells and analyzing the corresponding immune infiltrate, we determined the adaptations associated with resistance to therapy. We found that evasion of immunotherapy was associated with a “hypermetabolic” phenotype, characterized by an upregulation of glycolytic, oxidoreductase, and mitochondrial oxidative phosphorylation pathways to establish a hypoxic, metabolically hostile microenvironment. Enforced expression of two key genes associated with these pathways in parental tumor cells was sufficient to mediate resistance to triple checkpoint blockade. Flow cytometry assays determined that T cells infiltrating resistant tumors had diminished glycolytic capacity and effector function, indicating a metabolic disadvantage. Consistent with our findings, melanoma patients who failed dual checkpoint blockade exhibited similar metabolic alterations as seen in our resistant variant. Using a novel MRI-based imaging approach, we observed distinct metabolic changes that stratified responding versus nonresponding tumors in live mice. Applying this method to patients could provide insight into predicting response rates to checkpoint modulation. Overall, our data indicate that resistant melanoma tumor cells acquire a “hypermetabolic” phenotype to establish a hostile microenvironment that is capable of inhibiting the antitumor immune response. This abstract is also being presented as Poster A24. Citation Format: Ashvin R. Jaiswal, Arthur J. Liu, Shivanand Pudakalakatti, Prasanta Dutta, Priyamvada Jayaprakash, Todd Bartkowiak, Casey Ager, Zhiqiang Wang, Alex Reuben, Zachary Cooper, Cristina Ivan, Zhenlin Ju, Felix Nwajei, Jing Wang, Michael A. Davies, R. Eric Davis, Jennifer A. Wargo, Pratip K. Bhattacharya, David S. Hong, Michael A. Curran. Melanoma evolves complete immunotherapy resistance through acquisition of a hypermetabolic phenotype [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr PR02.

Evofosfamide (TH-302) is a clinical-stage hypoxia-activated prodrug of a DNA-crosslinking nitrogen mustard that has potential utility for human papillomavirus (HPV) negative head and neck squamous cell carcinoma (HNSCC), in which tumor hypoxia limits treatment outcome. We report the preclinical efficacy, target engagement, preliminary predictive biomarkers and initial clinical activity of evofosfamide for HPV-negative HNSCC. Evofosfamide was assessed in 22 genomically characterized cell lines and 7 cell line–derived xenograft (CDX), patient-derived xenograft (PDX), orthotopic, and syngeneic tumor models. Biomarker analysis used RNA sequencing, whole-exome sequencing, and whole-genome CRISPR knockout screens. Five advanced/metastatic HNSCC patients received evofosfamide monotherapy (480 mg/m2 qw × 3 each month) in a phase 2 study. Evofosfamide was potent and highly selective for hypoxic HNSCC cells. Proliferative rate was a predominant evofosfamide sensitivity determinant and a proliferation metagene correlated with activity in CDX models. Evofosfamide showed efficacy as monotherapy and with radiotherapy in PDX models, augmented CTLA-4 blockade in syngeneic tumors, and reduced hypoxia in nodes disseminated from an orthotopic model. Of 5 advanced HNSCC patients treated with evofosfamide, 2 showed partial responses while 3 had stable disease. In conclusion, evofosfamide shows promising efficacy in aggressive HPV-negative HNSCC, with predictive biomarkers in development to support further clinical evaluation in this indication.

The prognosis for patients with newly diagnosed acute lymphoblastic leukemia (ALL) has improved with the use of more intensive chemotherapy regimens, tyrosine kinase inhibitors, targeted agents, and allogeneic hematopoietic cell transplantation. However, the management of relapsed or refractory (R/R) ALL remains challenging and prognosis is poor. The NCCN Guidelines for ALL provide recommendations on standard treatment approaches based on current evidence. These NCCN Guidelines Insights summarize treatment recommendations for R/R ALL and highlight important updates, and provide a summary of the panel's discussion and underlying data supporting the most recent recommendations for R/R ALL management.

Immune checkpoint blockade is effective in “hot” tumors like melanoma with pre-existing immune infiltrates; however, “cold” tumors like prostate cancer fail to respond. We found that prostate cancers harbor regions of hypoxia that resist T cell infiltration even in the context of anti-CTLA-4 (cytotoxic T lymphocyte associated protein-4) and anti-PD-1 (programmed cell death protein 1) blockade. These hypoxic zones serve as islands of immune privilege through the recruitment and suppressive polarization of immature myeloid cells into myeloid-derived suppressor cells (MDSC) and tumor-associated macrophages (TAM). We found that targeted hypoxia ablation using TH-302, a hypoxia-activated prodrug, sensitized both transplantable and spontaneous models of prostate cancer to checkpoint blockade, coincident with enhanced T cell infiltration and effector function and loss of MDSC recruitment and suppressive function. Tumors treated with the combination of TH-302 and checkpoint blockade showed a reduced capacity to suppressively polarize new myeloid immigrants, implying a durable reconditioning of the tumor microenvironment (TME) into an immune-infiltrated, pro-inflammatory milieu. T cells infiltrating combination-treated tumors exhibited increased mitochondrial respiration, consistent with creation of a metabolically favorable milieu for T cell function. Based on these findings, we hypothesized that other approaches capable of metabolically rewiring the TME should promote anti-tumor immunity and sensitize checkpoint blockade-resistant tumors to immunotherapy. With this in mind, we performed a longitudinal study comparing a panel of different mitochondrial respiration inhibitors and a glutaminase inhibitor for their efficacy in reducing hypoxia, improving T cell infiltration and decreasing myeloid cell recruitment and suppressive polarization using immunofluorescence staining and confocal microscopy. Our preliminary data suggests that inhibitors targeting mitochondrial respiration, rather than those targeting glutamine metabolism synergize with checkpoint blockade and exhibit the highest efficacy in increasing T cell recruitment. We continue to characterize the dynamics of hypoxia reduction, duration of normalization following drug withdrawal, and impact on the immune microenvironment of these diverse approaches to metabolic reconditioning. Citation Format: Priyamvada Jayaprakash, Midan Ai, Arthur Liu, Pratha Budhani, Todd Bartkowiak, Jie Sheng, Casey Ager, Courtney Nicholas, Ashvin Jaiswal, Yanqiu Sun, Krishna Shah, Sadhana Balasubramanyam, Nan Li, Guocan Wang, Jing Ning, Anna Zal, Tomasz Zal, Michael Curran. Targeting hypoxia-induced immune suppression to overcome immunotherapy resistance in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5011.

Atypical teratoid/rhabdoid tumors (ATRT) are rare, highly malignant, embryonal CNS tumors with a poor prognosis. Therapy relies on highly toxic chemotherapy and radiotherapy. To improve outcomes and decrease morbidity, more targeted therapy is required. Gene expression analysis revealed elevated expression of multiple kinases in ATRT tissues. Aurora Kinase A was one of the candidate kinases. The objective of this study was to evaluate the impact of Aurora Kinase A inhibition in ATRT cell lines. Our analysis revealed that inhibition of Aurora Kinase A induces cell death in ATRT cells and the small molecule inhibitor MLN 8237 sensitizes these cells to radiation. Furthermore, inhibition of Aurora Kinase A resulted in decreased activity of pro-proliferative signaling pathways. These data indicate that inhibition of Aurora Kinase A is a promising small molecule target for ATRT therapy.

Background: Despite the success of T-cell checkpoint blockade antibodies in treating an array of cancers, the majority of patients still fail to respond to these therapies, or respond transiently and then relapse. The molecular mechanisms that drive lack of response to checkpoint blockade, whether pre-existing or evolved on therapy, remain unclear. Materials and Methods: To address this critical gap in clinical knowledge, we established a mouse model of melanoma designed to elucidate the molecular mechanisms underlying immunotherapy resistance. Through multiple in vivo passages, we selected a B16 melanoma tumor line that evolved complete resistance to combination blockade of CTLA-4, PD-1, and PD-L1, which cures ~80% of mice of the parental tumor. Using gene expression analysis, proteomics, and immunogenomics, we determined the adaptations engaged by this melanoma to become completely immunotherapy resistant. NMR spectroscopy, Seahorse XF analysis, flow cytometry, confocal microscopy, and Western blot analysis provided further insight into the mechanisms driving checkpoint blockade resistance. Results: Acquisition of immunotherapy resistance by these melanomas was driven by coordinate upregulation of the glycolytic and aldose reductase pathways to create a metabolically hostile microenvironment in which T-cell function is profoundly suppressed. When reintroduced into the parental tumor, the genes most closely associated with these metabolic adaptations confer enhanced immunotherapy resistance. We have validated upregulation of these pathways in a unique cohort of melanoma patients who failed dual checkpoint blockade. Additionally, we employed MRI imaging to visualize metabolic changes acquired by resistant tumors in live mice. Clinical application of this technique could provide a much-needed noninvasive tool to predict immunotherapeutic sensitivity of patients. Conclusion: Upregulation of glycolytic metabolism and the aldose reductase pathway by melanoma tumor cells cripples T cells in the microenvironment and confers resistance to checkpoint blockade. This abstract is also being presented as Poster A71. Citation Format: Ashvin R. Jaiswal, Shivanand Pudakalakatti, Prasanta Dutta, Arthur Liu, Todd Bartkowiak, Casey Ager, Cristina Ivan, Richard Eric Davis, Michael A. Davies, Jennifer Wargo, James P. Allison, Pratip K. Bhattacharya, David Hong, Michael A. Curran. Metabolic adaptations establish immunotherapy resistance in melanoma [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2017 Oct 1-4; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2018;6(9 Suppl):Abstract nr PR08.