bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract CT060: ACTION: A randomized phase 3 study of dordaviprone (ONC201) in patients with newly diagnosed H3 K27M-mutant diffuse glioma
Authors: Arrillaga-Romany Isabel , Lassman Andrew , McGovern Susan L. , Mueller Sabine , Nabors Louis B. , van den Bent Martin , Vogelbaum Michael , Allen Joshua E. , Melemed Allen S. , Tarapore Rohinton S. , Yang Dewen , Wen Patrick , Cloughsey Timothy
Published: April 2023

Background: H3 K27M-mutant diffuse midline glioma is a universally fatal malignancy primarily affecting children and young adults. While radiotherapy (RT) provides transient benefit, no effective systemic therapy is currently available and current standard of care is RT followed by monitoring. Dordaviprone (ONC201), a first-in-class imipridone, is an oral, blood-brain barrier penetrating, selective small molecule antagonist of dopamine receptor D2/3 (DRD2) and agonist of the mitochondrial protease ClpP. An integrated pooled analysis of five open-label trials previously demonstrated efficacy in dordaviprone-treated patients with recurrent disease. This phase 3 trial will be the first randomized, controlled study evaluating dordaviprone in patients with H3 K27M-mutant disease.

Methods: ACTION (NCT05580562) is a randomized, double-blind, placebo-controlled, parallel-group, international Phase 3 study of dordaviprone in patients with newly diagnosed H3 K27M-mutant diffuse glioma. Patients who have completed standard frontline radiotherapy will be randomized 1:1:1 to receive placebo, once-weekly dordaviprone, or twice-weekly dordaviprone on two consecutive days. Primary efficacy endpoints are overall survival (OS) and progression-free survival (PFS) in all participants; PFS will be assessed by response assessment in neuro-oncology-high grade glioma by blind independent central review. Other objectives include assessments of safety, additional efficacy endpoints, clinical benefit, quality of life, pharmacokinetics, biomarkers, and healthcare resource utilization. Eligible patients will have histologically confirmed H3 K27M-mutant diffuse glioma, a Karnofsky/Lansky performance status ≥70, and completed first-line radiotherapy. Eligibility will not be restricted based on age; however, patients must be ≥10 kg at time of randomization. Patients with a primary spinal tumor, diffuse intrinsic pontine glioma, leptomeningeal disease, or cerebrospinal fluid dissemination are not eligible. ACTION is currently enrolling in the United States, with additional sites to be open internationally in 2023.

Citation Format: Isabel Arrillaga-Romany, Andrew Lassman, Susan L. McGovern, Sabine Mueller, Louis B. Nabors, Martin van den Bent, Michael Vogelbaum, Joshua E. Allen, Allen S. Melemed, Rohinton S. Tarapore, Dewen Yang, Patrick Wen, Timothy Cloughsey. ACTION: A randomized phase 3 study of dordaviprone (ONC201) in patients with newly diagnosed H3 K27M-mutant diffuse glioma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT060.
Abstract CT137: ENLIGHTen-01: a phase 1 study of fluorescein-specific (FITC-E2)-car T cells in combination with folate-fluorescein (UB-TT170) for osteosarcoma
Authors: Albert Catherine M. , Pinto Navin R. , Taylor Mallory , Wilson Ashley , Rawlings-Rhea Stephanie , Narayanaswamy Prabha , Huang Wenjun , Seidel Kristy , Mgebroff Stephanie , Brown Christopher , Garcia Jacob , Teoh Jeffrey , Orentas Rimas J. , Gardner Rebecca A. , Jensen Michael C. , Park Julie R.
Published: April 2023

Background: Outcomes for relapsed osteosarcoma (OS) remain poor and there are no systemic therapies that have been shown to provide a survival benefit. Chimeric Antigen Receptor (CAR) T cell immunotherapy involves the adoptive transfer of T-lymphocytes that have been engineered to recognize tumor-specific antigens, resulting in targeted lysis of malignant cells. Folate receptors (FR) are membrane-bound surface proteins that bind folates with high affinity. FRs are overexpressed in OS and have very limited expression in normal tissue. UB-TT170 (Umoja Biopharma) is a small molecule bispecific “adapter” consisting of folate conjugated to fluorescein (FL). It penetrates tumors in minutes and is retained for long periods of time due to high affinity for the FR, while unbound UB-TT170 rapidly clears from the blood and from FR- tissues. We hypothesize that administration of fixed dosing anti-FL(FITC-E2) CAR T cells followed by escalating doses of UB-TT170 will deliver personalized immunotherapy to OS patients. In addition, this approach offers an attractive safety mechanism since administration of NaFL should reverse CAR T cell reactivity.

Methods: We designed a Phase I study for young adult (15-30 yr) patients with recurrent/refractory OS to examine the safety and feasibility of administering autologous, peripheral blood-derived T cells that have been genetically modified to express a 2nd generation FL-specific CAR in combination with intra-subject dose escalation of UB-TT170. The primary objective is to identify a recommended dose escalation sequence of UB-TT170 to move forward in clinical development. A 3+3 design will be used to investigate 3 possible dosing sequences. The trial opened in July 2022. As of January 5, 2023, 5 subjects have enrolled and one subject has been treated on dose regimen 1. T cell products have been successfully manufactured for all enrolled subjects. The trial remains open to enrollment. Clinical trial registration numbers: NCT05312411

Citation Format: Catherine M. Albert, Navin R. Pinto, Mallory Taylor, Ashley Wilson, Stephanie Rawlings-Rhea, Prabha Narayanaswamy, Wenjun Huang, Kristy Seidel, Stephanie Mgebroff, Christopher Brown, Jacob Garcia, Jeffrey Teoh, Rimas J. Orentas, Rebecca A. Gardner, Michael C. Jensen, Julie R. Park. ENLIGHTen-01: a phase 1 study of fluorescein-specific (FITC-E2)-car T cells in combination with folate-fluorescein (UB-TT170) for osteosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT137.
Abstract CT189: A phase I study of BAT1006, a novel anti-HER2 antibody, in patients with locally advanced/metastatic solid tumors
Authors: Mei Xingxing , Tang Weijia , Song Shuqiang , Wang Hao , Cao Chuanqi , Feng Cuiying , Thomas Bert E. , Li Shengfeng , Yu Jin-Chen
Published: April 2023

Purpose: BAT1006 is a HER2 extracellular domain II-targeted monoclonal antibody with enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) effect aiming for Her2-positive locally advanced/metastatic solid tumors. Previous studies have shown that de-fucosylated antibody binds to FcγRIIIa with increased affinity and can thus trigger FcγRIIIa-mediated effector functions more efficiently than native antibody. BAT1006 was expressed in an FUT8-knockout CHO cell line, resulting in antibody completely devoid of fucose modification. With approximate 5-fold higher level of ADCC effect compared to Pertuzumab, BAT1006 also exhibited potent anti-tumor activity in HER2 positive Calu-3 xenograft mice model. The ongoing phase I, open-label, first-in-human study is evaluating the safety, pharmacokinetics (PK), immunogenicity and preliminary efficacy of BAT1006 to determine the Maximum-Tolerated Dose (MTD) and/or recommended phase II dose (RP2D).

Methods: Patients with locally advanced/metastatic solid tumors received escalating doses of BAT1006 (3, 6, 10, 15 mg/kg), administered intravenously (IV) once every three weeks. Patients must have had documented HER2 positivity defined as 3+ by validated immunohistochemistry or amplified on in situ hybridization (ISH). Assessments include archival tumor molecular status, PK, and efficacy by Response Evaluation Criteria in Solid Tumors (RECIST).

Results: Fifteen patients [with 2-9 prior lines of therapy] have been treated with BAT1006. All patients had metastatic breast cancer and had received previous HER2-targeted therapies including Trastuzumab, Pertuzumab, T-DM1 and Pyrotinib. No treatment related ≥ Grade 3 AEs have been observed. Of 9 patients at 10mg/kg and 15mg/kg, 1 in 3 patients had CR at 10mg/kg, 2 in 6 patients had PR at 15mg/kg.

Conclusion: BAT1006 was well tolerated and showed promising anti-tumor activity in patients with heavily pre-treated HER2-positive cancers. Based on the safety and efficacy results, one additional dose level (20 mg/kg) will be added to the escalation phase and combination therapy with other HER2-based therapy will also be initiated.

Citation Format: Xingxing Mei, Weijia Tang, Shuqiang Song, Hao Wang, Chuanqi Cao, Cuiying Feng, Bert E. Thomas, Shengfeng Li, Jin-Chen Yu. A phase I study of BAT1006, a novel anti-HER2 antibody, in patients with locally advanced/metastatic solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT189.
Abstract CT232: Safety, efficacy, and tolerability of FHND9041 capsules as first-line treatment in patients with EGFR sensitive mutations or second/third-line treatment in patients with T790M+ advanced non-small cell lung cancer (NSCLC): results from a phase I/II single-arm, multi-center, open-label study
Authors: Zhu Yongqiang , Shang Minghong , Wang Jia , Yang Nong , Dong Xiaorong
Published: April 2023

Background: FHND9041 is a third-generation EGFR inhibitor independently developed by Nanjing Chuangte Pharmaceutical Technology Co., Ltd. It irreversibly binds to EGFR protein, and demonstrates strong inhibitory effect on EGFR T790M mutations as well as EGFR sensitive mutations. This is the first single-arm, multi-center, open-label phase I/II study of FHND9041 capsule, which evaluates the safety, tolerability and preliminary efficacy of FHND9041 capsule in initial treatment of NSCLC with EGFR sensitive mutations or treatment of T790M+ advanced NSCLC who progressed after prior EGFR-TKI therapy.

Methods: 124 subjects tested for EGFR mutations and eligible for evaluation were randomized to dose groups of 40 mg, 80 mg (first-line treatment or second/third-line treatment with T790M+), 120 mg and 180 mg. The primary endpoint is objective response rate (ORR), and key secondary endpoints are progression-free survival (PFS), disease control rate, duration of response, and safety.

Results: The ORR of FHND9041 capsule 80 mg (recommended phase 2 dose, RP2D) is 71.43% in patients newly diagnosed of NSCLC with EGFR sensitive mutations, and 63.64% in patients with T790M+ NSCLC who had progressed after prior EGFR-TKI therapy. No DLT occurred in all dose groups, 40 mg, 80 mg and 120 mg, which demonstrated satisfactory tolerability and safety of FHND9041. Detailed efficacy data of each dose group is shown in the table below.

Conclusion: FHND9041 capsule 80 mg shows significant antitumor activity with favorable efficacy and safety profile in patients for both initial treatment and treatment of T790M+ NSCLC who progressed after prior therapy. For futher research of the capsule, a multicenter, randomized, positive-controlled phase III clinical research is ongoing with recommended dose of 80 mg.

Group Dosage(mg) Evaluable Subjects(n) ORR% Second/Third-line T790M+ 40mg 3 33.33 80mg 39 63.64 120mg 42 58.33 180mg 3 100.00 First-line 80mg 37 71.43

Citation Format: Yongqiang Zhu, Minghong Shang, Jia Wang, Nong Yang, Xiaorong Dong. Safety, efficacy, and tolerability of FHND9041 capsules as first-line treatment in patients with EGFR sensitive mutations or second/third-line treatment in patients with T790M+ advanced non-small cell lung cancer (NSCLC): results from a phase I/II single-arm, multi-center, open-label study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT232.
Abstract LB004: Ultra-sensitive targeted DNA panel for very low-frequency mutation detection in circulating cell-free DNA
Authors: Baird Michelle , Ashraf Mariam , Chistensen Emil , Haldrup Christa , Wu Zhong , Lader Eric
Published: April 2023

Due to its noninvasive nature and being readily available in peripheral blood and other bodily fluids, analysis of cell-free DNA (cfDNA) has become a promising application in cancer diagnosis, prognosis and treatment monitoring. However, disease-relevant cfDNA is present in a very limited amount in the huge background of normal cfDNA. This remains a challenge for any detection technology. Many currently available target enrichment and library preparation methods use regular DNA polymerase and amplification processes that introduce substantial bias and artifacts. This results in artifactual errors that greatly limit the detection of true low-frequency variants below 0.5% in heterogeneous samples, such as cfDNA. Here, we present a new targeted cfDNA workflow that overcomes challenges such as biases and artifacts. The workflow uses a highly optimized, high-fidelity reaction chemistry and incorporates UMIs into a single gene-specific, primer-based targeted enrichment process. Compared to regular DNA polymerase, this high-fidelity chemistry resulted in a five- to ten-fold decrease in base substitution error. An individual cancer panel was designed to specifically cover cancer-relevant hotspots and copy number genes with a dense primer design to accommodate the short length of cfDNA. Due to its high-fidelity chemistry and optimal panel design, our streamlined workflow can be completed in a single day. We also report consistent panel performance across different samples. Detection sensitivity and specificity were evaluated on a reference cfDNA sample and a simulated cfDNA sample by mixing enzyme-digested Genome in a Bottle samples, NA12878 and NA24385. We achieved close to 90% detection sensitivity and above 99.9% specificity for 0.1% variant. In addition, copy number variation could be successfully detected with a 1.5-fold difference over normal control samples. These results demonstrate an efficient targeted cfDNA panel workflow that enables cancer-relevant mutation detection with high sensitivity and accuracy. The applications presented here are for research use only. Not for use in diagnostic procedures.

Citation Format: Michelle Baird, Mariam Ashraf, Emil Chistensen, Christa Haldrup, Zhong Wu, Eric Lader. Ultra-sensitive targeted DNA panel for very low-frequency mutation detection in circulating cell-free DNA [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB004.
Abstract LB005: Insights of renal cell carcinoma from multiomic perspective
Authors: Bartha Aron , Darula Zsuzsanna , Munkacsy Gyongyi , Klement Eva , Fenyo David , Nyirady Peter , Gyorffy Balazs
Published: April 2023

Introduction: Clear cell renal carcinoma is the most frequent form of renal malignancy, with an increasing incidence rate worldwide. In this study we used a multi-omic approach to differentiate normal and tumor tissues in clear cell Renal Cell Carcinoma (ccRCC).

Methods: Using transcriptomic data of patients with malignant and adjacent normal tissue samples from gene chip and RNA-Seq cohorts, we identified the top genes over-expressed in ccRCC. We collected surgically resected ccRCC specimens to further investigate the transcriptomic results on the proteome level. The differential protein abundance was evaluated using targeted mass spectrometry (MS).

Results: We assembled a database of more than 600 renal tissue samples from NCBI GEO and TCGA and used these to uncover the top genes with higher expression in ccRCC. For protein level analysis 162 malignant and normal kidney tissue samples have been acquired. The most consistently upregulated genes were IGFBP3, PLIN2, PLOD2, PFKP, VEGFA, and CCND1 (p<1E-05 for each gene). Mass spectrometry further validated the differential protein abundance of these genes (IGFBP3, p = 7.53E-18; PLIN2, p = 3.9E-39; PLOD2, p = 6.51E-36; PFKP, p = 1.01E-47; VEGFA, p = 1.40E-22; CCND1, p= 1.04E-24). We also identified proteins correlating with overall survival.

Conclusions: We used transcriptomic and proteomic data to identify a minimal panel of proteins highly specific for clear cell renal carcinoma tissues. The introduced gene panel could be used as a promising tool in the clinical setting.

Citation Format: Aron Bartha, Zsuzsanna Darula, Gyongyi Munkacsy, Eva Klement, David Fenyo, Peter Nyirady, Balazs Gyorffy. Insights of renal cell carcinoma from multiomic perspective [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB005.
Abstract LB010: LY6K depletion modulates TGF-β and EGF signaling
Authors: Yang Young , Park Sujeong
Published: April 2023

Lymphocyte antigen 6 complex locus K (LY6K), a glycosylphosphatidylinositol-anchored protein, plays a dynamic role in cancer metastasis. In the current study, we deciphered the effects of LY6K on transforming growth factor-β (TGF-β) and epidermal growth factor (EGF) signaling through clathrin- and caveolin-1 (CAV-1)-mediated endocytosis. LY6K expression level is elevated in higher grade cervical cancer patients correlating with poor overall survival, progression-free survival, and disease-free survival. LY6K-depletion in HeLa and SiHa cancer cells suppressed EGF-induced proliferation and TGF-β-enhanced migration and invasion. Both TGF-β receptor-I (TβRI) and EGF receptor (EGFR) localized at the plasma membrane regardless of LY6K expression, and LY6K bound TβRI irrespective of the presence of TGF-β; however, LY6K did not bind EGFR. LY6K-depleted cells showed impaired SMAD2 phosphorylation upon TGF-β treatment and lower proliferation rates following long-term treatment with EGF. We revealed the atypical movement of TβRI and EGFR from plasma membrane upon ligand stimulation in LY6K-depleted cells and an impaired movement of the endocytic proteins clathrin and CAV-1. Subsequently, transmission electron microscopy showed no clathrin and CAV-1-coated vesicles in LY6K-depleted cells. Our study demonstrates the key role of LY6K in both clathrin- and CAV-1-mediated endocytic pathways regulated by TGF-β and EGF, and it suggests a correlation between LY6K overexpression in cervical cancer cells and poor overall survival.

Citation Format: Young Yang, Sujeong Park. LY6K depletion modulates TGF-β and EGF signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB010.
Abstract LB029: AWT030: a first-in-class bi-functional IL-21 fusion protein selectively activates tumor infiltrated CD8 T cells and suppresses Treg cells
Authors: Ye Fan , Huang Jianing , Chen Sandra , Li Ella , Jiang Jenny , Lin Hanna , Hua Michael , Huang Danny , Huang Zoey , Kwan Joyce , Cheng Lili , Zhong Ziyang
Published: April 2023

The tumor microenvironment (TME) has been identified as a significant obstacle to the success of immunotherapy, including anti-PD-1 therapy. The TME comprises several factors that limit the response rate to immunotherapy, including immunosuppressive cells such as regulatory T cells (Tregs), which directly or indirectly interact with effector cells and undermine the tumor recognition, activation, proliferation, and survival of the effector cells, thereby promoting tumor growth. To overcome suppressive TME, we designed AWT030, a first-in-class bi-functional IL-21 fusion protein that comprises a stability and potency optimized IL-21 mutein and an engineered functional domain that targets T cells. AWT030 is designed to selectively activate tumor-infiltrating CD8 T cells and suppress Tregs while avoiding the potential suppressive effect of IL-21 on dendritic cells.Compared to wild-type IL-21, mAWT030 greatly enhances the tolerability, half-life, and anti-tumor activity. In anti-PD-1 therapy resistant breast cancer EMT6 model, fibrosarcoma MCA205 model, and anti-PD-1 therapy responsive colon cancer MC38 model, mAWT030 achieved 100% complete response without noticeable toxicity, demonstrating a powerful synergy between tumor specific CD8 T cell activation axis and Treg suppression axis induced simultaneously by mAWT030. In addition, mAWT030 also exhibited a strong synergistic effect with anti-PD-1 antibody. Immunophenotyping revealed that AWT030 had minimal impact on circulating lymphocytes while altering the suppressive TME, with a significantly increased CD8 T cell population and suppressed Treg population. In summary, AWT030 is a novel bi-functional IL-21 fusion protein with high tumoral specificity, the excellent safety and antitumor activity of mAWT030 observed preclinically supports clinical development, focusing on treating PD-1 resistant/relapsed patients or combining with anti-PD-1 therapy.

Citation Format: Fan Ye, Jianing Huang, Sandra Chen, Ella Li, Jenny Jiang, Hanna Lin, Michael Hua, Danny Huang, Zoey Huang, Joyce Kwan, Lili Cheng, Ziyang Zhong. AWT030: a first-in-class bi-functional IL-21 fusion protein selectively activates tumor infiltrated CD8 T cells and suppresses Treg cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB029.
Abstract LB036: IRF8 regulates tumor cell sensitivity to intrinsic ferroptosis by repressing p53
Authors: Poschel Dakota , Kehinde-Ige Mercy , Klement John , Yang Dafeng , Merting Alyssa , Savage Natasha , Shi Huidong , Liu Kebin
Published: April 2023

Tumor cell resistance to ferroptosis, which is a recently discovered CTL induced cell death pathway, remains incompletely understood. We report here that interferon regulatory factor 8 (IRF8) functions as a regulator of tumor cell intrinsic ferroptosis. Genome-wide gene expression profiling identified ferroptosis pathway as an IRF8-regulated pathway in tumor cells. IRF8.KO tumor cells are resistant to intrinsic ferroptosis induction and also exhibit decreased ferroptosis in response to tumor specific CTL killing. Loss of IRF8 increases p53 express in tumor cells and knocking out Tp53 in IRF8.KO cells restored tumor cell sensitivity to intrinsic ferroptosis induction. We were able to show that treating tumor-bearing mice with IRF8-encoding plasmid NTC9385R-mIRF8 encapsulated in a DOTAP-cholesterol lipid nanoparticle significantly reduced tumor growth and increased the percentage of dead cells in the tumor. Our data therefore determine that IRF8 represses p53 expression to maintain tumor cell sensitivity to intrinsic ferroptosis.

Citation Format: Dakota Poschel, Mercy Kehinde-Ige, John Klement, Dafeng Yang, Alyssa Merting, Natasha Savage, Huidong Shi, Kebin Liu. IRF8 regulates tumor cell sensitivity to intrinsic ferroptosis by repressing p53 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB036.
Abstract LB039: Ovarian cancer cell-derived exosomal UCA1 reprograms glucose metabolism in stromal fibroblasts
Authors: Nadhan Revathy , Ha Ji Hee , Jayaraman Muralidharan , Kashyap Srishti , Dhanasekaran Danny N.
Published: April 2023

Tumor progression is stringently regulated by the co-ordinated signaling between the tumor cells and the tumor microenvironment (TME) through diverse autocrine, paracrine and exocrine signaling mechanisms. Recent studies have shown that the exosomes that play a crucial role in the transfer of oncogenic macromolecules and oncometabolites to different cellular components of the TME can be targeted for therapy. Therefore, with the focus on identifying the exosomal long non-coding RNA (lncRNA) that can be therapeutically targeted, we investigated the profile of ovarian cancer cell derived lncRNAs and their functional role in ovarian cancer pathophysiology. Analysis of exosomes derived from a panel of high grade serous ovarian cancer cell lines indicated that UCA1 (Urothelial Cancer Associated 1) is the most abundantly packaged lncRNA in the exosomes. Similarly, exosomes from patient-derived ovarian cancer cells exhibited higher levels of UCA1. Ascites from ovarian cancer patients also indicated high levels of UCA1 in the ascites-derived exosomes. Results using PKH67-labelled ovarian cancer cell-derived exosomes and MRC5 fibroblast cell line indicated the exosomal transfer of UCA1 to the fibroblasts. Since paracrine signaling has been shown to induce metabolic reprogramming of peritumoral fibroblasts, we interrogated whether exosomal transfer of UCA1 could reprogram the glucose metabolism in the fibroblasts. Results from the Agilent Seahorse glycolytic stress assay indicate that the exosomal UCA1 promotes reprogramming of glucose metabolism in fibroblast cells while depleting of UCA1 in the exosomes failed to induce such metabolic reprogramming. Results from the analysis of the key glycolytic enzymes in the stromal fibroblasts, post-exosomal UCA1 uptake also corroborate this conclusion. Thus our results provide primary evidence that the exosomal-UCA1 induces pro-tumorigenic metabolic reprogramming in peri-tumoral fibroblasts. Together with the known oncogenic role of UCA1 in many different cancer cells, our findings indicate that targeting UCA1 could form a productive precision cancer strategy in ovarian cancer, targeting both the tumor cells and tumor stromal cells. This research was supported by the Department of Defense Ovarian Cancer Research Program Award W81XWH-18-1-0066, W81XWH-22-1-0415, the National Institute of General Medical Sciences grant P20 GM103639 and The National Cancer Institute of the National Institutes of Health grant P30 CA225520.

Citation Format: Revathy Nadhan, Ji Hee Ha, Muralidharan Jayaraman, Srishti Kashyap, Danny N. Dhanasekaran. Ovarian cancer cell-derived exosomal UCA1 reprograms glucose metabolism in stromal fibroblasts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB039.
Abstract LB040: P62-mediated degradation of TIF-IA drives the senescence associated secretory phenotype
Authors: Thoms Hazel , Stark Lesley
Published: April 2023

Advanced age is one of the most significant risk factors for malignancy. One mechanism proposed for age-associated cancer risk is the accumulation of senescent cells in ageing tissue. These cells secrete a cocktail of pro-tumorigenic factors known as the senescence associated secretory phenotype (SASP). The SASP is driven by the NF-κB transcription factor. However, the initial triggers of NF-κB in senescence remain unclear. Here we describe a novel mechanism that triggers NF-κB and the SASP. Using multiple in vitro and in vivo models, we demonstrate accumulation and cytoplasmic to nuclear translocation of the PolI complex component, TIF-IA, upon senescence induction. siRNA knockdown revealed TIF-IA is not required for the cell cycle effects of senescence but is essential for transcription of SASP factors, nucleolar enlargement (a characteristic of senescence and marker of organismal ageing) and full senescence. We make the novel observation that in steady state, TIF-IA is targeted for autophagosomal degradation by the cargo receptor, p62, which is inhibited in senescence and promoted by inactivation of the DNA repair protein, ATM. Based on these data, we propose a model whereby the P62-TIF-IA interaction is lost downstream of DNA damage and ATM activation, which causes TIF-IA accumulation, the SASP and senescence. Using tissue from the well characterized nfkb1− / − mouse model of aging, and old and young mice, we show that TIF-IA accumulates in colonic mucosa with age, which is further enhance by nfkb1 deletion. These exciting new data identify a new role for TIF-IA and have considerable relevance to age-related cancer.

Citation Format: Hazel Thoms, Lesley Stark. P62-mediated degradation of TIF-IA drives the senescence associated secretory phenotype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB040.
Abstract LB041: EZH2 and ATF6 sense metabolic stress to balance MHC class I antigen presentation in melanoma
Authors: Edmondson Jacob L. , Reed Megan R. , Morehead Lauren C. , Heflin Billie , Koss Brian , Tackett Alan J.
Published: April 2023

Unleashing the immune anti-tumor response through immune checkpoint inhibitors (ICIs) is a promising strategy to combat many solid-tumor malignancies, including metastatic melanoma. When successful, the anti-tumor response is potent; however, around half of melanoma patients fail to respond to ICIs. Patient responsiveness to ICIs has been characterized by increases in MHC class I (MHC-I) expression driven by increases in oxidative metabolism. Though the harsh conditions of the tumor microenvironment (TME) are known to be immunosuppressive, the specific mechanisms connecting metabolic stress and antigen presentation are not well understood. To recapitulate and investigate the ICI-responsive phenotype in vitro, a model of metabolic remodeling was developed which forces melanoma cells (A375, A101D, B16F10) to metabolically adapt to the absence of glucose. Proteomic profiling indicates a reversible, adaptive phenotype reminiscent of published ICI-responders, and pathway enrichment shows analogous increases in oxidative metabolism and restoration of MHC-I expression. This phenotype, and its impact on MHC-I expression, significantly increases tumor cell sensitivity to T-cell-mediated killing in vitro. Additionally, successful adaptive remodeling of JAK1 and IFNAR1 KO cell lines suggests the metabolism-mediated induction of MHC-I is independent of IFN signaling. Proteomic analysis of three metabolically conditioned melanoma cell lines identified downregulation of the histone methyltransferase EZH2 (Enhancer of Zeste Homolog 2) and the activating transcription factor ATF6 as key determinants of MHC expression. In these studies, we mechanistically explore the control of MHC-I antigen presentation through the transcriptional and post-translational dysregulation of ATF6 and EZH2. Here, we demonstrate that ATF6 overexpression, and thereby activation of the adaptive unfolded protein response (UPR), prevents induction of MHC by EZH2 inhibition. These data suggest EZH2 and ATF6 act to balance MHC-I antigen presentation during metabolic stress whereby loss of EZH2 increases and activation of ATF6 prevents MHC antigen presentation. Additional and ongoing studies coupling EZH2 and ATF6 inhibition will provide crucial insight into this mechanism and have the potential to influence adjuvant therapy development.

Citation Format: Jacob L. Edmondson, Megan R. Reed, Lauren C. Morehead, Billie Heflin, Brian Koss, Alan J. Tackett. EZH2 and ATF6 sense metabolic stress to balance MHC class I antigen presentation in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB041.
Abstract LB062: Identifying novel targets for CAR-T therapies from single cell RNA-sequencing data
Authors: Madan Sanna , Sinha Sanju , Schäffer Alejandro A. , Ruppin Eytan
Published: April 2023

Chimeric antigen receptor T (CAR-T) cell therapies have revolutionized cancer treatment. While CAR-T has yielded tremendous clinical success for patients with liquid tumors, its potential remains to be unleashed against solid tumors. One key challenge is identifying optimal targets for these therapies: cell surface proteins that are expressed highly and uniformly by a tumor’s constituent malignant cells, and minimally so by healthy tissues. Employing a systematic, data-driven analysis, we first charted the landscape of existing CAR-T targets in the clinic, identifying the leading targets in each indication based on tumor selectivity and safety metrics. Next, from patient tumor single cell transcriptomics data, we performed a genome wide search across many different solid tumor types to identify new and candidate CAR-T targets with better selectivity and safety scores than extant ones. Remarkably, in almost all indications, we could not find such better targets, testifying to the near optimality of the current target space, at least in accordance with our measures. However, one striking exception is HPV-negative head and neck squamous cell carcinoma (HNSC), for which there is currently a dearth of existing CAR-T targets in clinics. Specifically, our investigation has discovered 20 novel CAR-T targets for treating HNSC and one for treating glioblastoma more precisely and safely.

Citation Format: Sanna Madan, Sanju Sinha, Alejandro A. Schäffer, Eytan Ruppin. Identifying novel targets for CAR-T therapies from single cell RNA-sequencing data [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB062.
Abstract LB075: Cancers adapt to their mutational load by buffering protein misfolding stress
Authors: Tilk Susanne , Frydman Judith , Petrov Dmitri , Curtis Christina
Published: April 2023

In asexual populations that don’t undergo recombination, such as cancer, deleterious mutations are expected to accrue readily due to genome-wide linkage between mutations. Despite this mutational load of often thousands of deleterious mutations, many tumors thrive. How tumors survive the damaging consequences of this mutational load is not well understood. Here, we investigate the functional consequences of mutational load in 10,295 human tumors by quantifying their phenotypic response through changes in gene expression. Using a generalized linear mixed model (GLMM), we find that high mutational load tumors up-regulate proteostasis machinery related to the mitigation and prevention of protein misfolding. We replicate these expression responses in cancer cell lines and show that the viability in high mutational load cancer cells is strongly dependent on complexes that degrade and refold proteins. This indicates that upregulation of proteostasis machinery is causally important for high mutational burden tumors and uncovers new therapeutic vulnerabilities.

Citation Format: Susanne Tilk, Judith Frydman, Dmitri Petrov, Christina Curtis. Cancers adapt to their mutational load by buffering protein misfolding stress [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB075.
Abstract LB081: Concurrent characterization of somatic nucleotide mutations, 5mC, and 5hmC methylation in clinical research samples using a single nanopore sequencing assay
Authors: Aganezov Sergey , Rescheneder Philipp , Beaulaurier John , James Phillip , Juul Sissel
Published: April 2023

Genomic and epigenomic variants accumulate during cancer progression, resulting in a tumor consisting of heterogeneous collections of cells, or clones, with distinct profiles of genomic and/or epigenomic alterations. The ability to characterize a broad set of somatic (epi)genomic variations simultaneously, using a single sequencing assay, facilitates cancer research and can help inform treatment.

Here we describe a comprehensive approach to analyze native tumor DNA with long nanopore reads. First, we demonstrate that shallow (<1x) whole genome nanopore sequencing provides sufficient information to observe large-scale copy number aberrations. This enables rapid and affordable screening of samples with an aim of selecting those that contain variation(s) of potential interest; such samples can then be sequenced to higher coverages for a higher resolution picture of specific structural variants.

We further demonstrate an analysis workflow vimba for high coverage (>30x) nanopore sequencing of tumor/normal datasets that detects clone- and haplotype-resolved structural variations in patient-derived research samples. We provide an example of haplotype- and breakpoint-resolved compounded amplification and loss of heterozygosity (LOH) of a region containing the EGFR gene in an admixed kidney tumor sample.

Finally, we describe the suitability of this assay to gather genome-wide (epi)genomic variations (e.g., SNPs, indels, SVs, microsatellite instability) across tumor samples of different cancer types. For the first time with native long nanopore reads we are able to capture 5mC and 5hmC methylation information and map it over some of the most challenging repetitive regions of the genome. This information can empower a better understanding of cancer-type-specific (epi)genomic alterations, which in turn can help map out the landscape for further research.

Our approach demonstrates how nanopore sequencing can be used as a single comprehensive platform to better understand and resolve the complexity of (epi)genomic somatic alterations in tumor samples.

Citation Format: Sergey Aganezov, Philipp Rescheneder, John Beaulaurier, Phillip James, Sissel Juul. Concurrent characterization of somatic nucleotide mutations, 5mC, and 5hmC methylation in clinical research samples using a single nanopore sequencing assay [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB081.
Abstract LB087: IFN-gamma targets tumor vascular endothelial cells, causing impaired perfusion and tumor growth suppression in adoptive T cell therapy
Authors: Lin Qiaoya , Olkowski Colleen , Choyke Peter L. , Sato Noriko
Published: April 2023

CD8 T cell-secreted interferon-gamma (IFNγ) is a key factor in controlling adoptive T cell therapy (ACT) outcome. However, IFNγ effects on non-tumor cells (e.g., stroma and blood vessels) that could indirectly impact the therapy are not well characterized. We aim to dissect the spatiotemporal effects of IFNγ in the tumor microenvironment in ACT and the underlying mechanism of the therapy. An ACT using ex vivo-activated ovalbumin (OVA)-specific OT-1 T cells suppressed the growth of MCA-205-OVA-GFP fibrosarcoma or MOC2-SIINFEKL oral squamous cell carcinoma in wild-type mice. However, in IFNγR1-deficient hosts, the ACT failed, indicating that non-tumor cells were crucial targets of IFNγ. Furthermore, the efficacy was also abrogated in bone-marrow chimeras generated by transferring the wild-type bone-marrow to lethally irradiated Tie2-Cre-Ifngr1flox/flox mice. As IFNgR1 expression is specifically deficient in endothelial cells in these chimeras, this result indicates that IFNγ action on endothelial cells is indispensable for ACT. Early after T cell transfer (1.5 days), the fraction of OT-1 T cells infiltrating the tumor was small (0.098% of CD45+ cells) but produced high IFNγ (36.3%), resulting in the peak IFNγ concentration (47.3 pg/ml) in the whole tumor tissue in a 7-day observation period. In contrast, the highest accumulation of OT-1 T cells with low IFNγ production (2.9%) was observed on Day 4.5. Intravital imaging revealed that at Day 1.5, IFN-γ-RES-YFP-OT-1 T cells with a high level of IFNγ secretion (strong YFP+ signal) localized mainly along the tumor vessels. While more OT-1 T cells were observed in the MCA-205-OVA-GFP tumor tissue near the blood vessels on Day 4.5 than on Day 1.5, their IFNγ secretion was minimal. Degeneration of endothelial cells was observed via electron microscopy 3-4.5 days after T cells transfer. Consistent with this finding, CD31+ endothelial cell density decreased on Day 4.5 compared to Day 1.5 and significantly reduced blood perfusion in the entire tumor as observed by near-infrared imaging after IR800-albumin infusion. H&E staining of tumor sections showed tumor necrosis on Day 4-7. In summary, our study demonstrates that endothelial cell targeting of CD8 T cell-derived IFNγ is critical for tumor suppression in ACT, impairing blood perfusion. These results provide novel insights into the mechanism of ACT.

Citation Format: Qiaoya Lin, Colleen Olkowski, Peter L. Choyke, Noriko Sato. IFN-gamma targets tumor vascular endothelial cells, causing impaired perfusion and tumor growth suppression in adoptive T cell therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB087.
Abstract LB092: Identification of target antigens for logic-gated CAR-T therapeutics for the treatment of clear cell renal cell carcinoma: conditional targeting of CA9 with a PSMA PrimeR
Authors: Attanasio Nickolas , Gray-Rupp Levi , Zhou Stanley , Williams Samuel A.
Published: April 2023

Chimeric antigen receptor T (CAR T) cell therapeutics have produced curative outcomes in hematological malignancies but have yet to be developed into safe and effective therapies for solid tumors. A major obstacle to developing targeted therapies against solid malignancies is the identification of targets that are abundantly and broadly expressed on tumor cells while exhibiting an absence of expression on high toxicity risk normal tissues. Logic-gated CAR T cells that inducibly express CAR upon recognition of a target antigen by a secondary engineered priming receptor (PrimeR) offer a novel approach to permit conditional killing activity in the presence of two antigens. Here, we identify PSMA and CA9 as attractive priming and cytolytic antigen targets, respectively, in clear cell renal cell carcinoma (ccRCC). Using a bioinformatic discovery path, we show PSMA and CA9 mRNA are co-expressed in 94% of ccRCC tumors (n=530, TCGA). Immunohistochemical (IHC) assessments further reveal robust membranous PSMA and CA9 protein coexpression in 80% of ccRCC (n=416). Expression of CA9 and PSMA was evaluated across disease stage and co-expression was confirmed throughout disease progression. Distant metastases similarly showed evidence of common expression. In contrast, IHC assessment of normal tissues revealed limited membranous coexpression of PSMA and CA9 in normal high-risk toxicity tissues. These findings collectively support the utility of PSMA and CA9 as target antigens for AND-logic-gated therapeutics for the treatment of ccRCC.

Citation Format: Nickolas Attanasio, Levi Gray-Rupp, Stanley Zhou, Samuel A. Williams. Identification of target antigens for logic-gated CAR-T therapeutics for the treatment of clear cell renal cell carcinoma: conditional targeting of CA9 with a PSMA PrimeR [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB092.
Abstract LB121: BrainChild-03: Intraventricular B7-H3 CAR T cells for recurrent/refractory central nervous system tumors and non-pontine diffuse midline glioma in children and young adults
Authors: Vitanza Nicholas A. , Gust Juliane , Ronsley Rebecca , Wilson Ashley L. , Huang Wenjun , Seidel Kristy , Albert Catherine M. , Pinto Navin , Orentas Rimas J. , Gardner Rebecca A. , Jensen Michael C. , Park Julie R.
Published: April 2023

Background: B7-H3 expression on central nervous system (CNS) tumors offers a potential therapeutic target for adoptive cellular therapy.

Methods: A 3+3 statistical design was employed to assess the safety of repeated B7-H3 chimeric antigen receptor (CAR) T cells administered into the intracranial ventricular system (ICV) using an intrapatient dose escalation without lymphodepleting chemotherapy in pts 1-26 years of age with recurrent/refractory CNS tumors including (non-pontine) diffuse midline glioma (DMG) (NCT04185038, Arm B). Primary endpoints were feasibility to manufacture sufficient CARs and safety of weekly infusions for 3 weeks of 4-week cycles for 2 cycles. Secondary endpoints were best overall response (BOR) and correlatives of CAR activity.

Results: CAR manufacturing was achieved in 20/22 (91%) enrolled pts. Eight pts were inevaluable (rapidly progressive exam precluding initial infusion (n=5), removal from protocol therapy due to progressive disease (n=2), and lack of evaluable disease prior to initial infusion (n=1)). No dose limiting toxicities were observed, identifying the maximally tolerated dose regimen (MTDR) as DR3 (maximum dose: 10 × 107 B7-H3CARs). Subjects received 98 ICV doses (median: 6 doses/patient, range: 3-13). For evaluable patients, the most common adverse events were headache (12/12, 100%), fatigue (9/12, 75%), nausea/vomiting (7/12, 58%), and fever (6/12, 50%). There was no cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS). Imaging analysis is ongoing with current BOR being stable disease. CAR T cells were detected in the CSF in 9/12 evaluable pts (75%). Serial CSF/serum cytokine analysis and mass spectrometry are in process.

Conclusion: Repeated ICV administration of B7-H3 CAR T cells is tolerable with circulating CAR T cells detectable in the CSF post infusion. Further investigation is warranted, along with future studies interrogating iterative enhancements such as modifications for enhanced potency and multi-antigen targeting.

Citation Format: Nicholas A. Vitanza, Juliane Gust, Rebecca Ronsley, Ashley L. Wilson, Wenjun Huang, Kristy Seidel, Catherine M. Albert, Navin Pinto, Rimas J. Orentas, Rebecca A. Gardner, Michael C. Jensen, Julie R. Park. BrainChild-03: Intraventricular B7-H3 CAR T cells for recurrent/refractory central nervous system tumors and non-pontine diffuse midline glioma in children and young adults [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB121.