bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4963: Heme Sequestration as an effective strategy for the suppression of tumor growth and progression of SCLC
Authors: Ashrafi Adnin , Salamat Narges , Berisha Eranda , Alemi Parinaz Sadat , Castro Maria Del Carmen Chacon , Akter Zakia , Zhang Li
Published: April 2023

Small-cell lung cancer (SCLC) accounts for 15% of all lung cancers with exceptionally high proliferative rate, early metastasis, and poor prognosis. Chemotherapy has provided SCLC patients considerable survival benefits over the past three decades. Etoposide-platinum (EP) is the preferred first-line regimen. SCLC is initially highly responsive to cisplatin and etoposide chemotherapy, but in almost every case becomes rapidly chemo resistant. Despite attempts to improve outcomes utilizing multiple different strategies, drug resistance remains a major obstacle in clinical consequences of patients with SCLC. Recent research aims to elucidate mechanisms of resistance to improve drug response and treatment outcomes. Our lab has shown that limiting heme via inhibition of heme uptake using heme sequestering peptide (HeSP2) can delay growth and progression of NSCLC tumors. This HeSP2 can also effectively inhibit angiogenesis, normalize tumor vasculature, and alleviate tumor hypoxia in NSCLC tumors and thereby inhibit lung tumor advancement. Here we aim to determine if HeSP2 can be used to enhance the therapeutic efficacy of traditional chemotherapy in the treatment of SCLC. Our preliminary results show that HeSP2 can effectively reduce cell proliferation of SCLC cells like H889 and H720. To understand the mechanism by which the heme sequestering protein limit tumor development, we generated human SCLC H889 xenograft lung tumor model in NOD/SCID mice subcutaneously. Mice were treated with saline (control), HeSP2 alone, cisplatin-etoposide, and HeSP2-cisplatin-etoposide in combination. Tumor growth was monitored using caliper measurements. Tumors tissues were harvested, processed and paraffin embedded for immunohistochemistry (IHC) and histology experiments. The results imply that heme sequestration can be a potential strategy for suppressing small cell lung cancer tumor progression and improve survival outcome of patients.

Citation Format: Adnin Ashrafi, Narges Salamat, Eranda Berisha, Parinaz Sadat Alemi, Maria Del Carmen Chacon Castro, Zakia Akter, Li Zhang. Heme Sequestration as an effective strategy for the suppression of tumor growth and progression of SCLC. [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 4963.
Abstract 5083: Investigating the development and therapeutic potential of intra-tumoral CXCR6+ effector/effector memory T cells (TEFF/EM) in triple-negative breast cancer
Authors: Lim Bryan Jian Wei , Wang Xiao-Fan , Li Qi-Jing
Published: April 2023

Triple-negative breast cancer (TNBC) is an aggressive subtype that makes up 10-20% of all breast cancer cases. Because of the higher risk of metastasis and recurrence post-treatment, there is a need to develop novel therapeutics to address these challenges. In previously published work, we demonstrated that CXCL16 traps CXCR6+PD-1+ effector/effector memory (TEFF/EM) within the primary tumor and that these T cells have anti-metastatic function that can be harnessed when released into peripheral sites with intra-tumoral administration of anti-CXCL16 prior to surgical resection. However, whether CXCL16 blockade can be used in combination with conventional checkpoint targets and the developmental route of this CXCR6+ TEFF/EM is not known. To develop a novel neoadjuvant therapy, we use the spontaneously metastasizing murine TNBC model, 4T1. Here, we report that anti-4-1BB, and not anti-PD-1, when used in combination with blockade of CXCL16 can prolong survival post-surgical resection. Using anti-4-1BB in combination with CRISPR-generated Cxcl16-KO 4T1 model, we show that both deficiency of CXCL16 within the tumor microenvironment (TME) and anti-4-1BB contribute synergistically to survival advantage. To study the development of this population of T cells, we use the Py8119 murine TNBC model. We definitively show that CXCR6+PD-1+ TEFF/EM is uniquely generated within the primary tumor. Co-expression of CXCR6 and PD-1 indicates that T cell receptor (TCR) signaling is a potential regulator of the development of this TEFF/EM sub-population. Analyses of our previously published scRNA-seq dataset reveals Lat2 to be the top gene involved in TCR signaling. Tumors growing on Lat2-KO animals show a significant increase in tumor size accompanied by significant reduction of CD44high/mid CXCR6+PD-1+ TEFF/EM. However, competitive transfer of naïve WT and Lat2-KO T cells into Tcra-KO recipients led to comparable levels of CXCR6+ TEFF/EM. Surprisingly, transferred Lat2-KO T cells failed to engraft within the primary tumor relative to WT T cells. Future work will address if this engraftment defect is due to expansion/survival defects. Therefore, regulation of TCR signaling within the TME via LAT2 potentially represents a mechanism in which primary tumors trap T cells, promoting their exhaustion. Importantly, this can be harnessed through combinatorial activation and blockade of 4-1BB and CXCL16 respectively.

Citation Format: Bryan Jian Wei Lim, Xiao-Fan Wang, Qi-Jing Li. Investigating the development and therapeutic potential of intra-tumoral CXCR6+ effector/effector memory T cells (TEFF/EM) in triple-negative breast cancer. [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 5083.
Abstract 5085: Blockade of tumor derived CSF1 promotes an immune-permissive tumor microenvironment
Authors: Maldonado Maria Del Mar , Hamilton Duane H. , Schlom Jeffrey
Published: April 2023

The macrophage colony stimulating factor 1 (CSF1) is a chemokine essential for the survival, proliferation, and differentiation of especially mononuclear phagocytes, such as macrophages and monocytes. However, within the tumor microenvironment (TME), CSF1 regulates the production, survival, and recruitment of tumor associated macrophages (TAMs), further promoting a protumorigenic and immunosuppressive M2-like phenotype. Overexpression of CSF1 in breast, prostate, and ovarian cancers has been shown to promote tumorgenicity, invasiveness, and accelerate tumor metastasis. In this study, we demonstrate for the first time, that treating established murine MC38 colon and 4T1 breast carcinoma tumors with a CSF1R blocking antibody promotes the expansion of neoepitope-specific T cells. To assess the role of tumor derived CSF1 in these model systems, we generated and characterized CSF1 CRISPR-Cas9 knockouts. In both models, elimination of tumor-derived CSF1 results in a decreased tumor growth in both syngeneic and immune-compromised mice as compared to the parental cell lines. Inhibition of CSF1/CSF1R signaling axis generated enhanced immunity against 4T1 and MC38 tumor neoepitopes, potentially promoting an immune permissive TME in tumor bearing mice. Combination of a neoepitope targeting cancer vaccine with anti-PDL1 in the MC38 CSF1-/- tumor model significantly decreased tumor growth in vivo. Furthermore, combining CSF1R blockade with adeno-TWIST1 vaccine decreased tumor volume, lung metastasis, and synergistically increased in CD8 T cell infiltration in 4T1 mammary tumors. Analysis of the tumor microenvironment demonstrated increased infiltration in CD8 T cells accompanied by a reduction in tumor associated macrophages following CSF1R inhibition in both tumor models. Our findings confirm the therapeutic potential of combining CSF1 targeting agents with vaccine agents to further modulate anti-tumor immune responses in the tumor microenvironment.

Citation Format: Maria Del Mar Maldonado, Duane H. Hamilton, Jeffrey Schlom. Blockade of tumor derived CSF1 promotes an immune-permissive tumor microenvironment. [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 5085.
Abstract 511: A small molecule CET019 inhibits progression of triple negative breast cancer
Authors: Dheeraj Arpit , Tailor Dhanir , Marques Fernando Jose , Grau Benedikt , Bermudez Abel , Pitteri Sharon , Malhotra Sanjay
Published: April 2023

Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer, which accounts for 15-20% of total diagnosed breast cancer cases with high rates of metastasis and recurrence. Metastatic breast cancer remains one of the leading causes of cancer related mortality in women. The majority of women with this disease relapse after curative-intent therapy for early breast cancer; while a smaller proportion present with distant metastases at initial diagnosis. Our efforts of developing effective therapies for TNBC have identified CET019, a novel small molecule that effectively inhibits the growth of breast cancer cells. We found that CET019 impedes the clonogenic potential and growth of triple-negative breast cancer cells (MDA-MB-231, MDA-MB-468, SUM159 and 4T1). CET019 treatment induces the G2/M phase cell cycle arrest in TNBC cells. Moreover, the mouse xenograft study with different TNBC models, found that CET019 inhibits growth and progression compared to vehicle control group. Metastatic nodules in the lungs were inhibited by CET019 compared to control group. Collectively, our in vitro and in vivo experiments, provide foundation to further develop CET019 as a potential drug candidate to treat patients with TNBCs.

Citation Format: Arpit Dheeraj, Dhanir Tailor, Fernando Jose Marques, Benedikt Grau, Abel Bermudez, Sharon Pitteri, Sanjay Malhotra. A small molecule CET019 inhibits progression of triple negative breast cancer [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 511.
Abstract 5146: In vitro neutrophil assays to support immuno-oncology drug development
Authors: Pieters Alanah , Vlaming Martijn , Lefevere Jezabel , Pattyn Sofie
Published: April 2023

Neutrophils have shown a lot of plasticity with important consequences on cancer disease progression and have been associated with multiple functions such as killing antibody-opsonized cancer cells, directly kill tumor cells through the release of reactive oxygen and nitrogen species and a controversial role in the tumor micro-environment with both pro- and anti-tumor roles. Studying neutrophil function in vitro can be done using the Incucyte® live imaging system to monitor antibody-dependent cell-mediated cytotoxicity (ADCC). Optimised in vitro assays using fresh human neutrophils and fluorescent-labeled tumor cells can be used to screen the potency of candidate therapeutics. Additionally, neutrophil chemotaxis can be monitored using transwell plates and live imaging via Incucyte®. Finally, multiplex cytokine and chemokine analysis after activation and stimulation of neutrophils can be evaluated using Luminex technology. When studying neutrophil activity in vitro, important factors such as access to fresh blood and optimized protocols for purifying untouched neutrophils are key for reproducible and reliable results.

Citation Format: Alanah Pieters, Martijn Vlaming, Jezabel Lefevere, Sofie Pattyn. In vitro neutrophil assays to support immuno-oncology drug development. [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 5146.
Abstract 5157: ATRA treatment induces an interferon response to reprogram the immunosuppressive tumor microenvironment and overcomes resistance to immune checkpoint inhibition in murine models of LKB1 deficient non small cell lung cancer
Authors: Crosson William P. , Li Rui , Salehi-Rad Ramin , Lim Raymond J. , Abascal Jensen , Kahangi Bitta P. , Reyes Edgar Perez , Oh Michael , Dumitras Camelia , Edgar Nico , Chew Ryan , Jacobo Rashel , Jing Zhe , Krysan Kostyantyn , Tran Linh M. , Dubinett Steven , Liu Bin
Published: April 2023

Lung cancer remains the deadliest form of cancer, claiming the lives of 1.8 million individuals worldwide in 2020. While treatment options have improved with the advent of immune checkpoint inhibitors (ICI), many patients do not respond to immunotherapy or develop resistance following initial response. A significant subset of non-small cell lung cancer (NSCLC) patients harbor somatic co-mutations in Kirsten rat sarcoma virus (KRAS) and Liver kinase 1 [LKB1, also known as serine/threonine kinase 11 (STK11)] genes, whose tumors are characterized by a predominance of neutrophils and an immune suppressive tumor microenvironment (TME) that are resistant to ICI. Our studies revealed that all-trans retinoic acid (ATRA), a metabolite derived from vitamin A, sensitized a murine model of NSCLC (Kras G12D P53−/−Lkb1−/−; KPL) to PD-1 blockade. The ATRA and anti-PD-1 combination therapy improved local and systemic T cell activation and generated systemic tumor-specific immunity. We further observed that ATRA augmented anti-PD-1 efficacy in additional murine NSCLC models with or without LKB1 loss. To understand ATRA-mediated anti-tumor effects, we performed single cell RNA sequencing (scRNA-seq) of KPL murine tumors with or without 6 daily ATRA treatments. scRNA-seq analysis indicated a reduction of neutrophils as well as an enrichment in T cell and natural killer (NK) cell populations in the TME. Furthermore, scRNA-seq analysis revealed elevated expression of interferon (IFN) downstream genes in multiple immune subpopulations in the TME. Preliminary ex vivo studies indicated that ATRA increases NOX2 levels, intracellular reactive oxygen species (ROS), and IFN signaling in the myeloid-derived suppressor cells (MDSC) of KPL tumors. Our findings suggest that ATRA may reshape the TME by activating IFN signaling in multiple cell subtypes to sensitize resistant tumors to ICI immunotherapy.

Citation Format: William P. Crosson, Rui Li, Ramin Salehi-Rad, Raymond J. Lim, Jensen Abascal, Bitta P. Kahangi, Edgar Perez Reyes, Michael Oh, Camelia Dumitras, Nico Edgar, Ryan Chew, Rashel Jacobo, Zhe Jing, Kostyantyn Krysan, Linh M. Tran, Steven Dubinett, Bin Liu. ATRA treatment induces an interferon response to reprogram the immunosuppressive tumor microenvironment and overcomes resistance to immune checkpoint inhibition in murine models of LKB1 deficient non small cell lung cancer. [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 5157.
Abstract 5168: In vitro suppressive Treg bioassays for screening of candidate therapeutics
Authors: Vlaming Martijn , Pieters Alanah , Lefevere Jezabel , Pattyn Sofie
Published: April 2023

The increasing interest in the tumor microenvironment leads to a focus on new bioassays to represent all the players of the cancer immune response. Some of these players like regulatory T cells play an important role by downregulating the anti-tumor response. Their regulation mechanisms constitute an important target for new therapeutics. In order to study these mechanisms in a human model, suppressive Treg bioassays mimicking the suppressive action of these cells were developed and optimized. In vitro suppressive assays come with many technical challenges, therefore protocols for the purification and in vitro culture of regulatory T cells were optimized and fine-tuned to result in an optimal assay window e and allow screening of multiple candidates. Donor-to-donor variation is controlled by pre-evaluation of multiple donors and standardized methods are used for isolation and in vitro culture of responding and suppressive cells. Access to a large and broad panel of healthy donors is required for the evaluation of therapeutic agents targeting the regulatory T cell pathway.

Citation Format: Martijn Vlaming, Alanah Pieters, Jezabel Lefevere, Sofie Pattyn. In vitro suppressive Treg bioassays for screening of candidate therapeutics. [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 5168.
Abstract 5178: Humanized OX40/OX40L mice as a tool for evaluating novel therapeutics
Authors: Liu Chonghui , Yao Jiawei , Zhou Xiaofei , Jin James , Zhang Zan
Published: April 2023

The use of immune-competent mouse models that express target human genes provide a promising preclinical platform aimed at developing novel immunotherapies. Emerging immunotherapies include targeting OX40 and OX40 ligand (OX40L), which can lead to enhanced T cell activation, proliferation, and effector function. Blocking the OX40/OX40L pathway improves autoantigen-specific T cell responses and decreases immunocompetence across several autoimmune diseases. To explore the potential of OX40 and OX40L antibody efficacy studies, we developed double humanized B-hOX40/hOX40L mice by replacing the extracellular domain sequences of murine Ox40 and Ox40l with the corresponding human sequences. We validated human OX40L gene expression by RT-PCR and OX40/OX40L protein expression by flow cytometry in B-hOX40/hOX40L mice. Additionally, percentages of splenic, blood, and lymph node immune cells were similar between B-hOX40/hOX40L and wild-type C57BL/6 mice. Altogether, this data demonstrates that B-hOX40/hOX40L mice are suitable for in vivo efficacy studies using anti-human OX40 and OX40L antibodies.

Citation Format: Chonghui Liu, Jiawei Yao, Xiaofei Zhou, James Jin, Zan Zhang. Humanized OX40/OX40L mice as a tool for evaluating novel therapeutics. [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 5178.
Abstract 5376: Protein structure-based modeling to improve MHC class I epitope predictions
Authors: Wilson Eric A. , Cava John Kevin , Chowell Diego , Singharoy Abhishek , Anderson Karen S.
Published: April 2023

The ability to accurately identify peptide ligands for a given major histocompatibility complex class I (MHC-I) molecule has immense value for targeted anticancer therapeutics. However, the highly polymorphic nature of the MHC-I protein makes universal prediction of peptide ligands challenging due to lack of experimental data describing most MHC-I variants. To address this challenge, we have developed a deep convolutional neural network, HLA-Inception, capable of predicting MHC-I peptide binding motifs using electrostatic properties of the MHC-I binding pocket. By approaching this immunological issue using molecular biophysics, we measure the impact of sidechain arrangement and topology on peptide binding, feature not captured by sequence-based MHC-I prediction methods. Through a combination of molecular modeling and simulation, 5821 MHC-I alleles were modeled, providing extensive coverage across human populations. Predicted peptide binding motifs fell into distinct clusters, each defined with different degrees of submotif heterogeneity. Peptide binding scores generated by HLA-Inception are strongly correlated with quantitative MHC-I binding data, indicating predicted peptides can be ranked, both within and between alleles. HLA-inception also showed high precision when predicting naturally presented peptides and can be used for rapid proteome-scale MHC-I peptide binding predictions. Finally, we show that the binding pocket diversity measured by HLA inception predicts response to checkpoint blockade.

Citation Format: Eric A. Wilson, John Kevin Cava, Diego Chowell, Abhishek Singharoy, Karen S. Anderson. Protein structure-based modeling to improve MHC class I epitope predictions. [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 5376.
Abstract 5537: Prognostic impact of sarcopenia in patients with metastatic castration sensitive prostate cancer
Authors: Iwamoto Hiroaki , Izumi Kouji , Mizokami Atsushi
Published: April 2023

Background/Aim: Recently, sarcopenia has been reported to be a useful prognostic factor in cancer patients, including prostate cancer patients. Gleason score, the presence or absence of visceral metastases, and the number of bone metastases, which were used in the LATITUDE and CHAARTED trials, are known prognostic factors for metastatic castration-sensitive prostate cancer (mCSPC). Although a large proportion of patients with mCSPC are elderly, the significance of sarcopenia in metastatic castration-sensitive prostate cancer is unknown.

Patients and Methods: Of 193 patients with mCSPC treated at Kanazawa University Hospital between 2000 and 2019, 150 patients with confirmed CT at diagnosis were included. Sarcopenia was determined based on the definition of Martin et al. Overall survival and prognostic factors were retrospectively evaluated.

Results: The median age was 72 years, median PSA 241 ng/mL, Gleason score (GS) ≥ 9 in 91 patients, visceral metastases in 23 patients, and sarcopenia in 106 patients. 109 patients (72.7%) were diagnosed as high risk by Latitude risk classification and 105 patients (70%) were diagnosed as high volume by Charted risk classification. All cause death was 64 patients, and the median follow-up period was 38.2 months. The median overall survival was 69.6 months. On multivariate analysis, GS ≥9 (P <0.0001, hazard risk =3.78), LDH ≥ 300 U/L (P <0.0001, hazard risk =2.88), and sarcopenia (P=0.04, hazard risk=2.07) were significant independent poor prognostic factors predicting shorter OS. The prognosis could be significantly stratified into a high risk group if two or more of these three factors were met and a low risk group if one or less was met (44 months vs. 106.4 months, P=0.0001, hazard risk=2.91). This classification more clearly stratified prognosis than the LATITUD classification (55.1 months vs. 135 months, P =0.027, hazard risk =1.8) or the CHAARTED trial classification (52.9 months vs. 135 months, P =0.009, hazard risk =1.98).

Conclusion: Sarcopenia that can assess general status was considered useful in the prognostic evaluation of patients with mCSPC.

Citation Format: Hiroaki Iwamoto, Kouji Izumi, Atsushi Mizokami. Prognostic impact of sarcopenia in patients with metastatic castration sensitive prostate cancer. [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 5537.
Abstract 5795: Leukemic stem cells confer ferroptosis resistance in aggressive blood cancer
Authors: Hassan Nunki , Yi Hangyu , Gaspard-Boulinc Lucie , Wang Jenny
Published: April 2023

Acute myeloid leukemia (AML) is an aggressive blood cancer with limited therapeutic options against leukemic stem cells (LSCs), resulting in poor clinical outcomes for decades. We have demonstrated the clinical importance of aberrant activation of RSPO3/β-catenin pathway in a subset of poor prognosis AML (Cancer Cell, 38:263-278, 2020) and its ability to sustain low levels of reactive oxygen species (ROS), a critical characteristic of human LSCs. This current study has extended our recent finding, and for the first time linked the pathway activation to ferroptosis resistance, a new drug resistance mechanism in cancer therapy. Our single-cell multiomics data in patient-derived xenograft mouse models of relapsed AML showed that the pathway activation in human LSCs led to upregulation of 43 differentially expressed genes associated with iron detoxification (e.g., FTH1) and ROS sensing/detoxification (e.g., PRDX1), two key features of ferroptosis resistance. Consistent with this observation, we found that AML patient specimens with favourable outcomes, which are independent of RSPO3 pathway, were sensitive to RSL3 treatment leading to increased cell death associated with elevated levels of intracellular ROS and iron. In contrast, AML patient specimens with poor clinical outcomes, which critically depend on RSPO3 pathway activation for survival and maintenance of myeloid undifferentiated state, revealed resistance to ferroptosis inducers (e.g., RSL3). Intriguingly, we found that anti-RSPO3 antibody, a clinical-grade drug that inhibits AML LSCs by blocking the interaction of RSPO3 with its receptor, sensitizes human LSCs to RSL3 treatment, leading to reduced cell viability. Overall, this study is the first to demonstrate the role of ferroptosis resistance in human LSCs and provides an opportunity to develop precision combination therapy by concurrently targeting self-renewal and ferroptosis resistance to improve therapeutic outcomes for patients with poor-risk AML.

Citation Format: Nunki Hassan, Hangyu Yi, Lucie Gaspard-Boulinc, Jenny Wang. Leukemic stem cells confer ferroptosis resistance in aggressive blood cancer [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 5795.
Abstract 582: IDO1 inhibition sensitizes metastatic lung tumors to hypoxia/ER stress targeting agent-induced cell death
Authors: Shen Shih-Chun , Dey Souvik , DuHadaway James B. , Prendergast George C. , Muller Alexander J.
Published: April 2023

IDO1 (indoleamine 2,3-dioxygenase), a tryptophan catabolic enzyme, has been demonstrated in our previous studies to support neovascularization by counteracting IFNγ-mediated anti-angiogenesis through IDO1-induced IL6. Physiologically, we observed that the reduced neovascularization associated with IDO1 loss was accompanied by increased intra-tumoral hypoxia within lung metastases of 4T1 breast tumors while eliciting little tumor cell death, lessening the prospects for direct clinical benefit. Several agents have been developed to be selectively cytotoxic under hypoxic/nutrient-deprived conditions, suggesting the potential for therapeutic cooperativity. Inhibiting PERK, a UPR (unfolded protein response) activator, has been shown to promote tumor cell apoptosis under hypoxic conditions both in vitro and in vivo. In Ido1-/- 4T1 tumor-bearing mice, administration of the PERK inhibitor GSK2656157 elicited pronounced metastatic tumor cell death that was elevated significantly over WT controls. Similarly, when WT 4T1 tumor-bearing mice were administered GSK2656157 together with the IDO1 inhibitors Epacadostat, Indoximod or Navoximod, the attenuated neovascularization and elevated regional hypoxia in lung metastases elicited by IDO1 inhibition was accompanied by an increased level of tumor cell death. Co-administration of the hypoxia-activated prodrug Evofosfamide with Epacadostat likewise resulted in elevated metastatic tumor cell death. This contrasts with results obtained with the non-targeted cytotoxic agent Carboplatin that elicited comparable levels of metastatic tumor cell death regardless of Epacadostat co-administration. Altogether, these data establish the potential to benefit treatment in tumor settings where IDO1 inhibition enhances intra-tumoral hypoxia through neovascular regression by facilitating the ability of hypoxia-targeting agents to effectively eliminate tumor cells in a more targeted manner than can be achieved with conventional chemotherapy.

Citation Format: Shih-Chun Shen, Souvik Dey, James B. DuHadaway, George C. Prendergast, Alexander J. Muller. IDO1 inhibition sensitizes metastatic lung tumors to hypoxia/ER stress targeting agent-induced cell death [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 582.
Abstract 5913: Semi-supervised analysis of myeloid and T cell behavior in ex vivo ovarian tumor slices reveals changes in cell motility after treatments
Authors: Laforets Florian , Kotantaki Panoraia , Malacrida Beatrice , Elorbany Samar , Manchanda Ranjit , Donnadieu Emmanuel , Balkwill Frances
Published: April 2023

Cell motility is an important component of anti-tumor responses, allowing immune cells like myeloid and cytotoxic T cells to infiltrate tumors. Using ex vivo human and mouse high-grade serous ovarian cancer (HGSOC) tumor slices combined with time-lapse imaging, we monitored the movement of CD8+ T and myeloid cells in live tumors, in real-time. To analyze the recordings and characterize immune cell movements, we developed a semi-supervised analysis, identifying four types of cell behavior: migrating, long migrating, static and wobbling. Tumor slices were maintained 24h ex vivo, retaining viability and cell movements. We show that ex vivo treatments with LPS altered CD8+ T and myeloid cell behavior. In vivo chemotherapy reduced ex vivo cell movements in human and mouse tumors, and differentially affected CD8+ T and myeloid cells in 60577 and HGS2 murine tumors, respectively chemo-sensitive and chemo-resistant mouse models, suggesting those cell types have different roles in the response to chemotherapy. Ex vivo tumor slices can extend in vivo mouse work to human, providing a stepping stone to translate mouse cancer studies to clinical trials.

Citation Format: Florian Laforets, Panoraia Kotantaki, Beatrice Malacrida, Samar Elorbany, Ranjit Manchanda, Emmanuel Donnadieu, Frances Balkwill. Semi-supervised analysis of myeloid and T cell behavior in ex vivo ovarian tumor slices reveals changes in cell motility after treatments [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 5913.
Abstract 5918: Interrogating host-intratumoral microbial interactions in pancreatic cancer
Authors: Chandra Vidhi , Rajaei Hajar , Baydogan Seyda , Gomez Javier , Ferri-Borgogno Sammy , Maitra Anirban , Riquelme Erick , Sahin Ismet , Burks Jared , Kim Michael , McAllister Florencia
Published: April 2023

Cancer is increasingly becoming a rising cause of mortality worldwide. Microbiota, both within the gut and tumors, has emerged as a significant player influencing tumor growth and responses to therapies. The tumor niche provides a privileged microenvironment for microbial colonization. Recent evidence links microbiota and pancreatic tumorigenesis. Pancreatic ductal adenocarcinoma (PDAC), is an aggressive cancer surrounded by a highly immuno-suppressive tumor microenvironment (TME) which limits efficacy of most available therapies. We have previously reported that rare long-term survival in pancreatic cancer is associated with an intratumoral microbial signature which correlates with enhanced TME immunoactivation, suggestive of microbial mediated immune cell recruitment. A gut-to-tumor microbial crosstalk was also found in a human-to-mouse Fecal Microbiota Transplant (FMT) tumor model. While we have identified the vital role of microbiota in affecting tumor immunity, there is still a gap of knowledge about local microbial interactions within TME. Deeper understanding of the microbial mediated events that are triggered and follow PDAC development, which act to induce and support tumor growth, would provide us with potential novel targets that could be blocked to reverse PDAC immunosuppression and tumor growth. To interrogate the features of the pancreatic tumor microbial niche, we performed spatial co-detection of microbial and host targets to identify the cellular compartment which interacts with microbes inside the TME in clinical samples. We developed novel qualitative and quantitative imaging methodologies for evaluating crosstalk between the host and microbes. We also evaluated the effect of microbial burden on transcriptomic changes in host cells through multiple spatial sequencing approaches. Overall, we dissect the functional role of microbes in orchestrating TME organization and their effect on tumor signaling.

Citation Format: Vidhi Chandra, Hajar Rajaei, Seyda Baydogan, Javier Gomez, Sammy Ferri-Borgogno, Anirban Maitra, Erick Riquelme, Ismet Sahin, Jared Burks, Michael Kim, Florencia McAllister. Interrogating host-intratumoral microbial interactions in pancreatic cancer [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 5918.
Abstract 594: Effects of interstitial pressure on lung cancer cells
Authors: Tokuda Shinsaku , Onoi Keisuke , Yamada Tadaaki , Takayama Koichi
Published: April 2023

Chronic inflammation is a risk factor for various types of cancer. The pressure in the interstitial tissues has been reported to be elevated in chronic inflammation and cancer. However, little is known about the biological effect of pressure from the basal side on epithelia, and a significance of the elevated interstitial fluid pressure in cancer biology is still poorly understood. In this study, we investigated the effect of hydrostatic pressure on cultured lung cancer cells grown on Transwell permeable filters by changing the height of the surfaces of culture medium in the apical and basal sides. A gradient of the hydrostatic pressure from the basal to the apical side induced stratification of epithelia. The elimination of the hydrostatic pressure gradient restored the stratification of epithelia. Interestingly, cavities were found within the stratified epithelia, and the characteristics of apical cell polarity including microvilli and tight junctions were formed in the surfaces the cavities. The cavities with similar aberrant cell polarity were also observed in human lung cancer tissues. The hydrostatic pressure gradient from the basal side also promoted cell proliferation and suppressed apoptosis. On the other hand, the expression levels of phosphorylated ERK and AKT were not significantly affected by the hydrostatic pressure. These results indicate that the pressure from the basal side to the epithelia promotes cell proliferation, suppresses apoptosis and induces aberrant cell polarity, which results in epithelial stratification. The findings in this study suggest that the elevated interstitial fluid pressure in chronic inflammation and cancer tissues facilitates cancer growth and plays a significant role in cancer biology.

Citation Format: Shinsaku Tokuda, Keisuke Onoi, Tadaaki Yamada, Koichi Takayama. Effects of interstitial pressure on lung cancer cells [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 594.
Abstract 5941: Sequencing of targeted- and immune-therapy: delineating time dependent changes in both melanoma cells and the immune microenvironment
Authors: Patel Riyaben , Trigos Anna , Haynes Nicole , Lelliott Emily , McArthur Grant , Sheppard Karen E.
Published: April 2023

Targeted and immune therapies have transformed outcomes for melanoma patients, nevertheless, significant challenges remain to maximize their clinical benefit. BRAF/MEK targeted therapy (TT) is associated with very high initial response rates that are typically short-lived, while in contrast Immune Checkpoint Inhibitors (ICI) provide more durable responses but have lower initial response rates. Hence, it has been proposed that sequencing ICIs with TT would lead to a higher frequency of durable responses. However, there are many unanswered questions regarding the choice of immunotherapy, the best sequencing strategy and the mechanism leading to this synergy. To address these questions, we have optimized a syngeneic mouse melanoma model, YUMMER1.7-PV1 that is sensitive to both TT and ICIs. Importantly, this model recapitulates the known three therapeutic response phases of targeted therapies: initial response, followed by drug tolerance and then resistance. Investigation of the tumor immune microenvironment (TIME) at these three drug-induced phases, demonstrates that the immune suppressive microenvironment present during the acquired resistant phase is primed at the drug tolerance phase. Utilizing this model, we have explored the time-dependent therapy-induced changes in both tumor cells and the TIME during various TT and ICI sequencing strategies. This information will determine the optimal sequencing strategy of targeted therapy and immunotherapy that will deliver better outcomes for melanoma patients.

Citation Format: Riyaben Patel, Anna Trigos, Nicole Haynes, Emily Lelliott, Grant McArthur, Karen E. Sheppard. Sequencing of targeted- and immune-therapy: delineating time dependent changes in both melanoma cells and the immune microenvironment [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 5941.
Abstract 5949: Modulate TAM infiltration at cancer-immune interface by targeting at monocyte migration
Authors: Du Wenxuan , Johnston Adrian , Nair Praful , Zhu Jingyi , Win Khin Sandar , Zhou Bryan , Phillip Jude , Wu Pei-Hsun , Wirtz Denis
Published: April 2023

Extensive infiltration of tumor-associated macrophages (TAMs) into the solid tumor microenvironment (TME), where they promote angiogenesis, initiate metastasis, and tune immunosuppression, has long been proven to correlate with worse patient prognosis. Thus, much significance has been attached on either impeding TAM infiltration or reversing pro-tumoral TAMs back into phagocytic M1 phenotype. Nevertheless, while revealing underlying mechanisms of blocking TAM recruitment, widely adopted in vitro migration assays like Transwell, µ-slides fail to distinguish cell’s random migration from chemotaxis (biased migration) and introduce 3D extracellular matrix environment. Here we present data that monocytes, as major replenishment source of TAMs, massively boost their random migration via paracrine pathway to initiate early-stage infiltration using an advanced 3D multi-compartment organoid model. In addition, before re-educated into TAMs, monocytes in the TME are capable of inducing triple negative breast cancer cells’ hyper-proliferation by activating their MEK/ERK signaling pathway. This work provides evidence that TAM infiltration is driven by monocytes’ random/biased migration separately and identifies a potential combinational immunotherapy targeting at monocytes instead of TAMs.

Citation Format: Wenxuan Du, Adrian Johnston, Praful Nair, Jingyi Zhu, Khin Sandar Win, Bryan Zhou, Jude Phillip, Pei-Hsun Wu, Denis Wirtz. Modulate TAM infiltration at cancer-immune interface by targeting at monocyte migration. [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 5949.
Abstract 5951: The correlation between single nucleotide polymorphism of chemokine receptor and ligand and infiltrating immune cells on tumor microenvironment of gastric cancer
Authors: Yoon Sunjoo , Lee Ju Hyun , Kang Minsu , Oh Hyeon Jeong , Koh Jiwon , Lee Hye Seung , Kang So Hyun , Park Young Suk , Lee Keun-Wook , Kim Jin Won
Published: April 2023

Objective: Chemokines play roles in many normal biological processes, such as hematopoietic cell genesis and leukocyte migration and homing. Chemokines could be responsible for eliciting local accumulation of immune cells within tumor microenvironment. In this study, we examine if genetic variations in chemokine receptor and ligand are associated with infiltrations of immune cells on tumor microenvironment in gastric cancer.

Methods: In 356 gastric cancer patients who received curative surgery followed by adjuvant chemotherapy, total 105 single nucleotide polymorphisms (SNP) in a chemokine ligand and chemokine receptor locus within 16 genes (CXCR4, CXCR2, CXCR1, CX3CR1, CCR8, CCR9, CCR3, CCR2, CCR5, CCRL2, CCR6, CXCR5, CCR6, CXCR6, CCR7, DARC) were genotyped from peripheral blood sample. Total 11 immune markers such as CD3, CD4, CD8, FOXp3, CD68, CD163, L-selectin, i-NOS, ADMA17, Arginase, CD45RO were analyzed for deposition of immune cells according to SNP of chemokine receptor and ligand. Levels of immunohistochemistry staining were quantified by Image Analysis Toolbox and density of immune cells infiltration was calculated.

Results: 32 SNP locus of 8 genes (such as CXCR1, CXCR2, CCR3, CCR2, CCR5, CCRL2, CCR6. CXCR5) were selected using 25% cut-off value of minor allele frequency (MAF). Among 8 genes, CCR5 was the most relevant gene for immune cell infiltration on tumor microenvironment. Intron1-2545G>A (rs1799987) were associated with increased accumulation of CD3+, CD68+ and FOXp3+ cells compared to recessive carriers of the common allele. In CCR5 SNP that contained the common alleles of intron1-2549 G>T (rs2734648) and exon2A-2081 A>G (rs1800023), CD3+, CD4+, CD8+ and FOXp3+ cells were infiltrated more than minor alleles.

Conclusions: The associations between infiltration of immune cells and SNP of chemokine receptor and ligand in gastric cancer were shown. Particularly, CCR5 SNP may be most relevant for correlation with infiltration of immune cells on tumor microenvironment.

Citation Format: Sunjoo Yoon, Ju Hyun Lee, Minsu Kang, Hyeon Jeong Oh, Jiwon Koh, Hye Seung Lee, So Hyun Kang, Young Suk Park, Keun-Wook Lee, Jin Won Kim. The correlation between single nucleotide polymorphism of chemokine receptor and ligand and infiltrating immune cells on tumor microenvironment of gastric cancer. [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 5951.
Abstract 5956: Tumor-infiltrating neutrophil progenitors impair homologous DNA repair and promote sensitivity to PARP-inhibition
Authors: Calcinotto Arianna
Published: April 2023

Tumor evolution is one of the major mechanisms responsible for acquiring therapy-resistant and more aggressive cancer clones. Whether the tumor microenvironment through immune-mediated mechanisms might promote the development of more aggressive cancer types is crucial for the identification of additional therapeutical opportunities. Here, we identified a novel subset of tumor-infiltrating neutrophils, defined as tumor-associated neutrophil progenitors (NePs). These NePs are enriched in highly proliferative hormone-dependent breast cancers and impair DNA repair capacity.  Mechanistically, succinate secreted by tumor-associated NePs inhibits homologous recombination, promoting error-prone DNA repair through non-homologous end-joining regulated by PARP-1. Consequently, breast cancer cells acquire  genomic instability, resulting in tumor progression and resistance to endocrine therapies.  Selective inhibition of these pathways induces increased tumor cell kill in vitro  and  in vivo. Intra-tumor NePs score correlates  with copy number alterations in highly proliferative hormone-dependent tumors from breast cancer patients. Treatment with PARP-1 inhibitors counteract the pro-tumorigenic effect of these neutrophils and reverses endocrine resistance.

Citation Format: Arianna Calcinotto. Tumor-infiltrating neutrophil progenitors impair homologous DNA repair and promote sensitivity to PARP-inhibition. [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 5956.
Abstract 5959: Dissecting the stromal drivers of gastroesophageal adenocarcinoma chemoresistance
Authors: Tai Kulsum , Pal Sanjima , Bérubé Julie , Kong Iris , Hoffman Adam , Bailey Swneke , Kirbizakis Aki , Huang Sui , Strasser Michael , Gibbs David , Bertos Nicholas , Sangwan Veena , Ferri Lorenzo
Published: April 2023

Gastroesophageal adenocarcinoma (GEA) is the fastest rising cancer in North America. Over the course of five years, the survival rate is <20%, creating an urgent need for appropriate treatments against GEA. Currently, providing patients with peri-operative systemic docetaxel triplet-based chemotherapy (DCF or FLOT) is the most effective approach to treat GEA. Despite this, for 50% of patients that do present an initial response to therapy, the tumor returns due to pre-existing or newly acquired resistance (i.e., chemoresistance) by the cancer. Researchers have shifted their focus to the tumor microenvironment (TME) as one of the factors influencing chemoresistance in patients. The TME is composed of tumor cells, immune cells and their secreted products, as well as fibroblasts. The components of the TME have been shown to interact with one another to influence tumor growth and progression. Fibroblasts are wound-healing cells that can be transformed into cancer-associated fibroblasts (CAFs) in response to stress and the release of inflammatory products. CAFs are the most abundant cells in the TME, yet their role in the chemoresponse of GEA is still unclear. Previous studies on other cancer types demonstrated that CAF expression is distinct between chemoresistant and chemo-sensitive tumors and certain CAF subpopulations may confer this resistance. This project will investigate the role of CAFs in the chemo-response of GEA using patient-derived organoids (PDOs) and CAFs from >200 GEA patients. A single-cell RNA sequencing atlas developed from >30 GEA DCF- or FLOT-treated patient samples will be used to identify CAF markers and targetable processes. CAF sub-populations will then be elucidated and correlated to tumor response. IF, FACS, and ELISA will be performed for subsequent CAF marker validation and characterization. Ex vivo drug testing with DCF or FLOT will be conducted on PDO-CAF co-cultures to recapitulate their drug response.

Citation Format: Kulsum Tai, Sanjima Pal, Julie Bérubé, Iris Kong, Adam Hoffman, Swneke Bailey, Aki Kirbizakis, Sui Huang, Michael Strasser, David Gibbs, Nicholas Bertos, Veena Sangwan, Lorenzo Ferri. Dissecting the stromal drivers of gastroesophageal adenocarcinoma chemoresistance [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 5959.