bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 404: LINE-1 retrotransposition promotes chromosomal translocations through RNA-templated DNA repair in human cancers
Authors: Tao Jianli , Alessandri Luca , Mendez-Dorantes Carlos , Burns Kathleen H. , Wang Qi , Chiarle Roberto
Published: March 2024

Introduction: Approximately 50% of human cancers have somatic integrations of long interspersed element-1 (LINE-1; also known as L1). L1 is a retrotransposon that copies itself through RNA and integrates into new genomic loci. Although L1 sequences comprise approximately 17% of the human genome, only 100-150 L1 loci have retained the ability to retrotranspose. These full-length, retrotransposition-competent L1s are typically repressed in human somatic cells, but there is evidence of their significant reactivation in human cancers. Therefore, L1 overexpression is a hallmark of many human cancers, particularly in highly malignant tumor types such as breast, ovarian, pancreatic, esophageal, lung, head-and-neck, colon, prostate, and liver cancers.

Results: In many cancers, chromosomal translocations are fundamental pathogenetic events initiated by the generation of DNA double-strand breaks (DSBs). Although LINE-1 (L1) retrotransposition events have been implicated in chromosomal rearrangements associated with most human cancers, the frequency and mechanisms by which L1 is involved in these rearrangements, including chromosomal translocations, remain poorly characterized. By combining high-throughput genome-wide translocation sequencing (HTGTS) and two sequencing techniques to detect L1 insertion sites (PolyA-seq and CELTICS-seq), we demonstrated that the presence of an active human L1 retrotransposition significantly increases the frequency of chromosomal translocations. By identifying L1-dependent translocation hotspots in HEK293T cells we highlight the requirement for the L1 reverse transcriptase (RT) activity and the crucial role of pre-existing DNA DSBs in promoting L1-mediated chromosomal translocations. L1-dependent translocation hotspots showed a marked preference for transcription end sites (TES) of active genes, early replication timing regions, and accessible chromatin regions. Therefore, while cancer genome analysis provides a static view of chromosomal rearrangements based on canonical L1 integrations, our functional studies reveal an unanticipated predominance of chromosomal translocations facilitated by non-canonical L1 retrotransposition via RNA-templated repair of existing DSBs, largely expanding our knowledge on the mechanism by which L1 retrotransposition induces genomic instability in human cancers.

Citation Format: Jianli Tao, Luca Alessandri, Carlos Mendez-Dorantes, Kathleen H. Burns, Qi Wang, Roberto Chiarle. LINE-1 retrotransposition promotes chromosomal translocations through RNA-templated DNA repair in human cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 404.
Abstract 4069: IL12-expressing genetically engineered myeloid cells remodel the stromal dense and T cell poor tumor microenvironment and premetastatic niche of F42010 murine osteosarcoma
Authors: Jackett Kailey , Browne Alice , Kaczanowska Sabina , Clements Miranda , Kaplan Rosandra , Wessel Kristin , Ball Brendan , Cronk James
Published: March 2024

Treatment options for patients with metastatic and recurrent osteosarcoma are poor. The development of immunotherapies for osteosarcoma has been hindered by the lack of immunocompetent preclinical models that recapitulate the stromal dense, myeloid-rich, T cell poor, and overall immunosuppressive microenvironment of human osteosarcoma. We hypothesized that the syngeneic murine osteosarcoma model F42010 may serve as a useful immunocompetent preclinical model of osteosarcoma suitable for developing novel immunotherapies for osteosarcoma. To test this, we used flow cytommetry, bulk RNA sequencing, and immunohistochemistry to characterize the stromal and immune compartments of this model. We found that the F42010 osteosarcoma model recapitulates the ECM-rich and immunosuppressive nature of human osteosarcoma primary tumor and pre-metastatic microenvironments, characterized by increased myeloid infiltrate expressing suppressive markers and lymphocyte exhaustion. Finally, we used this model to test the utility of a myeloid immunotherapy for osteosarcoma, IL-12 secreting genetically engineered myeloid cells (IL12-GEMys) that can reverse immune suppression in the pre-metastatic niche and tumor microenvironment. IL12-GEMy treatment augmented immune activation and significantly extended survival by delaying tumor growth. Our findings highlight that the F42010 osteosarcoma model effectively replicates key features of the osteosarcoma tumor microenvironment and is a valuable model for developing novel tumor microenvironment and pre-metastatic niche modulating immunotherapies for osteosarcoma.

Citation Format: Kailey Jackett, Alice Browne, Sabina Kaczanowska, Miranda Clements, Rosandra Kaplan, Kristin Wessel, Brendan Ball, James Cronk. IL12-expressing genetically engineered myeloid cells remodel the stromal dense and T cell poor tumor microenvironment and premetastatic niche of F42010 murine osteosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4069.
Abstract 4081: rhIL-7-hyFc (efineptakin-alfa, NT-I7) increases tumor-specific CD8+ T cells despite FOLFOX cytotoxicity effect
Authors: Lee Soung-Min , Kim Miyoung , Ferrando-Martínez Sara , Im Sun-Kyoung , Ji Mankyu , Choi Donghoon
Published: March 2024

rhIL-7-hyFc (efineptakin-alfa; NT-I7) is a potent T cell amplifier, comprised of two molecules of interleukin-7 (IL-7) fused to the hybrid Fc domain of IgD/IgG4 immunoglobulin. NT-I7 safely, significantly, and persistently increases the absolute lymphocyte counts (ALC) in humans in a dose-proportional manner. Importantly, this increase is primarily due to an increase in T cells (1). Previous studies have shown that NT-I7 not only significantly increases the number of CD8+ T cells in peripheral blood but also dramatically boosts the presence of tumor-infiltrating CD8+ T cells, including both tumor-specific (p15E+PD-1+) and tumor non-specific (PD-1-) CD8+ T cells in mice (2). FOLFOX is a chemotherapy regimen composed of 5-fluorouracil, leucovorin, and oxaliplatin that inhibits DNA duplication and eradicates rapidly dividing cells (3). Although the mechanism of FOLFOX results in direct tumor killing, it also has the potential to kill newly dividing lymphocytes during NT-I7 treatment (4-6). Therefore, in this study, we aimed to evaluate the feasibility of combining FOLFOX with NT-I7 in a syngeneic MC38 mouse tumor model. Our results show that NT-I7 improves the efficacy of FOLFOX, irrespective of the timing of NT-I7 administration: simultaneous administration or delayed 3 hours, or 2 days after FOLFOX administration. This improvement persists despite a significant decrease in ALC for the first 6 days, which was significantly lower than the ALC observed with FOLFOX alone. FOLFOX decreases the absolute numbers of tumor non-specific CD8+ T cells. However, adding FOLFOX does not affect the NT-I7-driven increase of tumor-specific CD8+ T cells within the tumor. Taken together, our data demonstrate that FOLFOX does not compromise NT-I7’s ability to increase tumor-specific T cells within the tumor and the combination enhances the anti-tumor response irrespective of the timing of NT-I7 administration.

Citation Format: Soung-Min Lee, Miyoung Kim, Sara Ferrando-Martínez, Sun-Kyoung Im, Mankyu Ji, Donghoon Choi. rhIL-7-hyFc (efineptakin-alfa, NT-I7) increases tumor-specific CD8+ T cells despite FOLFOX cytotoxicity effect [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4081.
Abstract 4084: Potent anti-tumor activity of ABN202 (anti-EGFR antibody-interferon-beta mutein) through direct cytotoxicity and indirect immune activation against non-small cell lung cancer, regardless of EGFR mutation status
Authors: Park Hee Geon , Cho Sung Hun , Park Ha Yeon , Jo Mi Gyoung , Park Ji Hyun , Seo Myeung Ryun , Kim Ji Hyun , Hong Sung Youl , Song Kyoung , Lee Chan Gyu , Jeong Hae Min , Lee Sae Hyung , Kim Na Young , Choi Jun Young , Shin Young Kee
Published: March 2024

Epidermal growth factor receptor (EGFR) is overexpressed or mutated in many patients with non-small cell lung cancer (NSCLC). Targeting EGFR mutation by tyrosine kinase inhibitors (TKIs) has significantly improved overall survival (OS) in patients with EGFR mutations. However, many patients experience tumor recurrence due to various resistance mechanisms. Therefore, there is an unmet medical need for new treatment strategies for patients with EGFR-positive NSCLC, regardless of EGFR mutation status. ABN202 is an antibody-cytokine fusion protein (ACFP) that serves as a platform technology compromising the IFN-β mutein (ABN102) fused to various antibodies for specific tumor targeting. In a previous study, we designed ABN202 (αEGFR) to comprise an EGFR targeting antibody (Cetuximab) and IFN-β mutein (ABN102) and we confirmed anti-cancer activities of ABN202 against EGFR-positive NSCLC. In this study, the direct cytotoxicity of ABN202 (αEGFR) was evaluated in human NSCLC cell lines with various driving mutations and EGFR expression levels. The indirect immune activation was tested in human peripheral blood mononuclear cells (PBMCs) and human IFNAR1/2 knock-in (KI) mice. The in vivo efficacy was evaluated in human NSCLC xenograft mouse models and human IFNAR1/2 KI mouse models. ABN202 (αEGFR) demonstrates potent anti-tumor activity through direct cytotoxicity and indirect immune activation in NSCLC, regardless of EGFR mutation status. Taken together, we suggest that ABN202 (αEGFR) is a promising drug candidate against NSCLC, regardless of EGFR mutation status.

Citation Format: Hee Geon Park, Sung Hun Cho, Ha Yeon Park, Mi Gyoung Jo, Ji Hyun Park, Myeung Ryun Seo, Ji Hyun Kim, Sung Youl Hong, Kyoung Song, Chan Gyu Lee, Hae Min Jeong, Sae Hyung Lee, Na Young Kim, Jun Young Choi, Young Kee Shin. Potent anti-tumor activity of ABN202 (anti-EGFR antibody-interferon-beta mutein) through direct cytotoxicity and indirect immune activation against non-small cell lung cancer, regardless of EGFR mutation status [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4084.
Abstract 4120: Adherent-to suspension transition by hematopoietic factors in metastatic dissemination of circulating tumor cells
Authors: Park Hyun Woo
Published: March 2024

Although metastasis is the foremost cause of cancer-related death, a specialized mechanism that reprograms anchorage dependency of solid tumor cells into circulating tumor cells (CTCs) during the metastatic cascade remains elusive. We discovered a biological phenomenon referred to as Adherent-to-Suspension Transition (AST) that reprograms adherent cells into suspension cells via aberrant induction of hematopoietic transcriptional regulators, which are hijacked by solid tumor cells to disseminate into CTCs. During dissemination, tumor microenvironment triggers epigenetic alteration of AST factors in the invasive front of solid tumors to evoke spontaneous cell-matrix dissociation, acquire anoikis resistance, and bypass immune surveillance of CTCs, however, in the absence of lineage differentiation and EMT. Using mouse models and de novo metastatic patient specimens, we uncovered how Adherent-Suspension Plasticity (ASP) dictates anchorage plasticity during the dissemination and colonization process within the metastatic cascade. Finally, we demonstrate therapeutic strategies that target AST factors to specifically abrogate CTC formation and suppress distant metastases. Together, these findings underscore an important early mechanism of how cancer cells spread and highlight novel targets for the development of anti-metastatic therapy. Furthermore, AST opens unexplored scenarios how reprogramming anchorage dependency orchestrates physiological events such as development, organ morphogenesis and immune cell activation.

Citation Format: Hyun Woo Park. Adherent-to suspension transition by hematopoietic factors in metastatic dissemination of circulating tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4120.
Abstract 4129: Mitochondria-targeted antioxidant MitoQ inhibits human breast cancer metastasis in mice
Authors: Capeloa Tania , Sonveaux Pierre
Published: March 2024

In oncology, the occurrence of distant metastases often marks the transition from curative to palliative care. Such outcome is highly predictable for triple-negative and HER2-positive breast cancer patients, even if tumors are detected early, and there is no treatment to prevent metastasis. Here, considering that mitochondria are bioenergetic sensors of the tumor microenvironment, we report in preclinical mouse models that human breast cancer relapse is not a fatality: local recurrence and metastatic dissemination can be prevented by MitoQ, a mitochondria-targeted antioxidant that already underwent Phase I safety and Phase II efficacy trials in humans for pathologies other than cancer. Metastatic prevention was confirmed in the MMTV-PyMT model of spontaneously metastatic mouse breast cancer. After oral delivery, MitoQ was effective at nanomolar concentrations at which nonmalignant cells were spared. In anticipation of future clinical trials, a robust signature of the response to MitoQ was defined, applicable to bulk primary tumor biopsies.

Citation Format: Tania Capeloa, Pierre Sonveaux. Mitochondria-targeted antioxidant MitoQ inhibits human breast cancer metastasis in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4129.
Abstract 4134: The abscopal effect of combination IRE with αPD-1 treatment against PDACs
Authors: Cao Qizhen , Egan Nicholas A. , Peng Weiyi , Li Chun
Published: March 2024

Pancreatic ductal adenocarcinoma (PDAC) is associated with a high capacity of metastatic dissemination, which results in a dismal 5-year relative survival rate. Irreversible electroporation (IRE) represents an innovative intervention utilizing short high-voltage electric pulses to induce cell death through either permanent membrane lysis or disruption of cellular homeostasis. Previous studies from our lab have demonstrated that the combination of IRE and immune checkpoint blockade using anti-PD-1 antibody (αPD-1) enhances the infiltration of CD8+ cytotoxic T cells, significantly prolonging survival in an orthotopic murine PDAC model. However, the impact of IRE/αPD-1 on metastatic PDAC tumors, known as the abscopal effect, remains unclear. In this investigation, we bilaterally implanted C57BL/6J mice with subcutaneous KRAS* PDAC tumors, treating the right flank tumors with or without IRE, in conjunction with or without αPD-1 administered intraperitoneally. Tumor growth in both the treated (with or without IRE) and untreated (abscopal) left flank tumors was closely monitored until humane euthanasia or long-term survival. In a separate study, mice serum and tumor tissues were collection on the 5th day post-IRE/αPD-1 treatment. Luminex cytokine assays were conducted on the collected serum, and immunostaining was performed on tumor tissue. Results demonstrated significantly enhanced antitumor activity in both IRE-treated and untreated tumors on mice treated with combined IRE and αPD-1, leading to a marked extension of overall survival. Luminex cytokine assays revealed a substantial increase in crucial cytokines, including IL-2, IFN-gamma, IL-18, IL-19, and IL-3, known for their pivotal roles in fostering cytotoxic T lymphocyte development, promoting T cell differentiation into effector T cells, and facilitating the recruitment of effector CD8+ T cells to the tumor microenvironment. Moreover, immunofluorescence staining of tumor tissue illustrated a notable accumulation of CD169+ macrophages in IRE-treated tumors compared to untreated tumors. Tumors from the combined IRE with αPD-1 group exhibited increased CD8+ T cell accumulation compared to other groups. These data suggest IRE combined with PD-1 blockade promotes robust antitumor immune, leading to systemic antitumor activity and robust abscopal effect.

Citation Format: Qizhen Cao, Nicholas A. Egan, Weiyi Peng, Chun Li. The abscopal effect of combination IRE with αPD-1 treatment against PDACs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4134.
Abstract 4146: Brain permeable bioluminescent substrates for NanoLuc based reporters
Authors: Gao Chao , Su Yichi , Wu Yan , Fitzgerald Connor , Uyeda Tetsuo H. , Wang Hui , Kirkland Thomas A. , Lin Michael Z. , Zhou Wenhui
Published: March 2024

Non-invasive imaging methods for tracking gene expression, cell growth and migration and other biological events in vivo are indispensable tools for biomedical studies. Bioluminescence imaging (BLI) can achieve sensitive detection with low background in vivo, which is desirable for body imaging of small animals. Yet, BLI in the central nervous system (CNS) is challenging because many luciferase substrates show limited permeability of the blood-brain-barrier (BBB). To address this issue, we developed a family of new brain-permeant NanoLuc (NLuc) substrates, cephalofurimazine (CFz). CFz family paired with Antares, a fusion of CyOFP and NLuc that emits orange light instead of blue, produces an order of magnitude more signal from the brain than the standard combination of D-luciferin with firefly luciferase and matches the peak output of AkaLumine with AkaLuc but without the need of ATP. One of the substrates in the family, CFz-9, not only produces outstanding signal as other CFz substrates when paired with Antares, but also is able to be formulated into lyophilized cake that can be reconstituted in aqueous buffers for i.p. injections. Toxicity studies demonstrate that CFz-9 and its reconstituted solutions are non-toxic to mice and thus multiple injections are allowed.

Citation Format: Chao Gao, Yichi Su, Yan Wu, Connor Fitzgerald, Tetsuo H. Uyeda, Hui Wang, Thomas A. Kirkland, Michael Z. Lin, Wenhui Zhou. Brain permeable bioluminescent substrates for NanoLuc based reporters [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4146.
Abstract 4153: PET/CT imaging of pancreatic ductal adenocarcinoma with a claudin-4 binding peptide in preclinical mouse model
Authors: Seo Jai Woong , Wang James , Kare Aris J. , Tumbale Spencer K. , Wu Bo , Raie Marina N. , Pandrala Mallesh , Ferrara Katherine W.
Published: March 2024

There is a critical need to develop new imaging and therapeutic strategies for pancreatic cancer. Current positron emission tomography (PET) imaging assessments of pancreatic ductal adenocarcinoma (PDAC) rely on 18F-FDG as a radiopharmaceutical. To increase the sensitivity of PDAC detection, we identified Claudin-4 (CLDN4), a tight junction transmembrane protein, as a PDAC biomarker through spatial transcriptomic and proteomic analyses. CLDN4 expression has previously been reported to be enhanced in 99% of primary and 100% of metastatic pancreatic cancer tissue samples and in 10 of 11 precancerous pancreatic intraepithelial neoplasia (PanIN) specimens. A small fragment of naturally occurring Clostridium perfringens enterotoxin (CPE) was previously reported to bind to the extracellular loop domain of CLDN4 protein (PDB:7kp4) with nanomolar (nM) affinity (Kd). A CLDN4 binding peptide (C4BP) was developed as a radioligand by modifying the n-terminus of C4BP which does not impact receptor binding. Here, we designed and synthesized a DOTA-PEG1-C4BP ligand on a rink amide resin using a microwave-assisted peptide synthesizer. Radiolabeling of DOTA-PEG1-C4BP (2 nmol) with 64CuCl2 (70 MBq) conferred 64Cu-C4BP (28 MBq/nmol) with 80% non-decay corrected yield and >99% radiochemical purity. PET/CT imaging of 64Cu-C4BP (~0.1 μg/mouse) performed in an inducible PDAC (KrasLSL-G12D/+;Rosa26LSL-tdTomato/LSL-tdTomato(KT);Ptf1aCreER;Trp53fl/fl) model at 84 day after tamoxifen injection resulted in ~25% injected activity per cubic centimeter (IA/cc) accumulation in metastases and at ~18% IA/cc retention in pancreatic tumors within 30 minutes of tail vein injection with minimal background accumulation. Ex vivo PET imaging confirmed the localized accumulation of 64Cu-C4BP in transgenic mice within the colon, pancreas, and liver. Blocking of 64Cu-C4BP accumulation with the cold compound in a xenograft model (NOD/SCID) bearing Capan-1 PDAC tumors demonstrated the specificity of 64Cu-C4BP binding. Here we report that CLDN4 is a promising target and 64Cu-C4BP is a promising ligand for the detection of pancreatic cancer.

Citation Format: Jai Woong Seo, James Wang, Aris J. Kare, Spencer K. Tumbale, Bo Wu, Marina N. Raie, Mallesh Pandrala, Katherine W. Ferrara. PET/CT imaging of pancreatic ductal adenocarcinoma with a claudin-4 binding peptide in preclinical mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4153.
Abstract 4161: Identification of pancreatic adenocarcinoma using urokinase plasminogen activator probe detected using optoacoustic imaging
Authors: Kim Vung , Chuong Phillip , Bynum Ryan , Grizzle William , McNally Lacey R.
Published: March 2024

Purpose: Diagnosing and treating pancreatic cancer remains a challenge. The hypovascularized nature of pancreatic cancer renders modern chemotherapeutics and cancer detection contrast agents ineffective. A promising approach to the challenges is the adoption of a novel imaging technique known as Multispectral Tomography (MSOT). We hypothesize that a urokinase plasminogen activator (UPA) probe will enhance the detection of orthotopic pancreatic cancer xenografts.

Methods: Pancreatic tumor cell lines (Panc1, MiaPaca-2, S2VP10, and S2C9) were assessed for UPA-receptor expression using western blot analysis. UPA peptide was synthesized and to the HiLyte-750 NIR dye. Flow cytometry and immunofluorescence were utilized to examine the specificity and activity of this UPA-750. The UPA-750 binding efficiency was assessed through a competitive inhibition assay with a UPAR-blocking antibody using fluorescence microscopy. Then SCID mice (5 mice/group) received orthotopic implantation of S2C9 (1.5 x 105) or MiaPaCa2 (2.0 × 106) pancreatic tumor cells. UPA-750 or 750 dye alone was IV injected into mice after the tumors reached 3mm. Biodistribution and accumulation of UPA-750 were observed through MSOT images taken at 2-hour intervals over 8 hours and at 24 hours. UPA-750 in the tumor, liver, and kidney was confirmed through ex vivo fluorescent imaging.

Results: UPAR expression was observed in every pancreatic cancer cell line, with the greatest relative abundance in S2P9 cells (3.0X), followed by S2VP10 (2.5X), Panc1 (1.77X), and MiaPaca-2 (1.3X). Application of the UPAR blocking antibody on S2CP9, S2VP10, MiaPaCa2, and SKOV3p1 (positive control) cell lines resulted in the inhibition of cellular binding of the UPA-750, as evidenced by fluorescence microscopy. UPA-probe was successfully observed in pancreas tumor slices with peak intensity at 4-hrs of imaging by MSOT. Ex vivo NIR fluorescence imaging confirmed UPA-750 signal in pancreatic tumors but not in liver or kidney.

Conclusion: UPA-probe exhibits potential as a marker for pancreatic cancer.

Citation Format: Vung Kim, Phillip Chuong, Ryan Bynum, William Grizzle, Lacey R. McNally. Identification of pancreatic adenocarcinoma using urokinase plasminogen activator probe detected using optoacoustic imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4161.
Abstract 4164: Hybrid photoacoustic imaging and fast ultrasound localization microscopy to probe the tumor microenvironment
Authors: Zhao Shensheng , Basu Sayantani , Campbell Roy H. , Zhao Yang , Chen Yun-Sheng
Published: March 2024

Photoacoustic (PA) imaging can map the physiological conditions of tissues and track the biodistribution of contrast agents. Ultrasound localization microscopy (ULM) with microbubbles provides deep-tissue super-resolution blood vessel images and blood velocity maps. The integration of these techniques offers a potential tool for oncological applications, such as visualizing tumor hypoxia and vasculature. Additionally, because PA imaging and ULM can share the same ultrasound detector and data-acquisition system, PA images can seamlessly fuse with ULM images without requiring post co-registration processing. However, the acquisition time of ULM is considerably longer (several minutes per frame) compared to PA imaging (10 milliseconds to 100 milliseconds per frame), limiting the simultaneous acquisition of the two imaging modalities. To address this issue, we developed a deep learning model based on U-Net to accelerate the frame rate of ULM using information from sparse microbubble locations and power Doppler images. By enabling fast ULM acquisition, we developed an interleaved PA/fast ULM imaging technique to simultaneously capture photoacoustic and ULM images. Our experiments demonstrated up to a 16 times improvement in acquisition speed with U-Net, utilizing in vivo mouse brain and skin tumor data. The hybrid imaging sequence achieved super-resolution vascular and tissue oxygenation imaging with less than 2 seconds of acquisition time per frame in vivo. The implementation of this rapid dual imaging scheme enables the longitudinal monitoring of 3D tumor microvasculature and hypoxia conditions using a common linear ultrasound transducer. We monitored tumor growth of epidermoid carcinoma (A431) in a mouse model from Day 7 to Day 17 of tumor implantation, and the results reveal a significant decrease in tumor vasculature density and oxygen saturation as the tumor grew larger over time. The results indicate a positive relationship between oxygen saturation and vessel density. Our findings showcase the potential of this innovative technique for advancing deep tissue, high-resolution, multi-biological parameters imaging in oncological research.

Citation Format: Shensheng Zhao, Sayantani Basu, Roy H. Campbell, Yang Zhao, Yun-Sheng Chen. Hybrid photoacoustic imaging and fast ultrasound localization microscopy to probe the tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4164.
Abstract 4186: Development of an orthotopic A549 lung carcinoma model in CD34+ humanized NCG mice and response to treatment with paclitaxel and pembrolizumab
Authors: Avrutskaya Anya , Rainbolt Elizabeth , John Bincy , Clouse Cara , Stackhouse Murray , Currie Christopher , Scatigno Sydney , Bronson Steven , Rowe Jenny , Hall Chassidy , Harris David P.
Published: March 2024

Translational in vivo models are needed to expedite the discovery of new treatments for lung cancer. One such approach is the use of humanized mouse models that enable immunotherapies targeting human immune cells to be evaluated for efficacy and tolerability. We developed an orthotopic lung carcinoma model in humanized mice (HuCD34 NCG), utilizing serial bioluminescence imaging to evaluate the activity of paclitaxel and pembrolizumab as single and combination agents. Paclitaxel, which disrupts microtuble function, and pembrolizumab, a PD-1-targeting immunotherapy, are both approved for the treatment of certain types of lung cancer. Paclitaxel kills cancer cells directly, and may also promote anti-tumor responses through enhanced presentation of tumor antigens and activation of T cells. Immunodeficient NCG mice were humanized with cord blood-derived hCD34+ stem cells from 3 donors. High levels of human cell engraftment, with expected frequencies of hCD45+ cells and other immune subsets, was observed by 14 weeks post-injection. Luciferase expressing A549 cells were implanted orthotopically into the pulmonary space of the left lobe of the lung, and animals were subsequently flux sorted into treatment groups. Tumor burden, measured by luciferase expression, increased progressively in untreated animals, and moribundity was often associated with clinical indications of respiratory distress. Treatment with paclitaxel significantly decreased the tumor burden and extended survival. In contrast, pembrolizumab did not control tumor growth or extend survival. There was no synergistic effect with the combination therapy, in fact, the addition of pembrolizumab was associated with a modest increase in tumor burden and disease progression. Comparative analysis of immune cell composition, function and persistence in lung and other tissues provided insights into the distinct pharmacodynamic responses associated with the different treatment regimens. This model establishes a robust in vivo platform to identify novel therapies for the treatment of lung cancer.

Citation Format: Anya Avrutskaya, Elizabeth Rainbolt, Bincy John, Cara Clouse, Murray Stackhouse, Christopher Currie, Sydney Scatigno, Steven Bronson, Jenny Rowe, Chassidy Hall, David P. Harris. Development of an orthotopic A549 lung carcinoma model in CD34+ humanized NCG mice and response to treatment with paclitaxel and pembrolizumab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4186.
Abstract 4187: Transcriptome profiling and characterization of peritoneal metastasis ovarian cancer xenografts in humanized mice
Authors: Kang Sung Wan , Lee Ji-young , Kang Ok-Ju , Kim Yong-Man , Choi Eun Kyung , Lee Shin-Wha
Published: March 2024

Background: Although immunotherapy has not yet been as successful in ovarian cancer (OC), it remains a potential therapeutic strategy. Preclinical models of OC are necessary to evaluate the efficacy of immuno-oncology (IO) drugs targeting human cancer and immune components but have been underutilized. Developing mouse models with a humanized (Hu) immune system can help understand the human immune response to IO drugs, including immune checkpoint inhibitors (ICIs), which have demonstrated limited effectiveness in OC patients.

Methods: We established OC xenograft Hu-mouse models by intraperitoneally injecting luciferase-expressing SKOV-3 Luc and OVCAR-3 Luc OC cells into CD34+ Hu-mice. Tumor growth was monitored through bioluminescence imaging (BLI). We assessed the efficacy of PD-1 blockade with pembrolizumab in the SKOV-3 Luc Hu-mouse model. The immune profiles of the tumors were characterized using colorimetric immunostaining and flow cytometry. Additionally, we analyzed RNA-seq data to investigate the gene expression signature of pembrolizumab refractory tumors.

Results: We confirmed tumor development in both OC cell lines within CD34+ Hu-mice. In these models, human lymphocyte and myeloid cell subsets were present in the tumors, draining lymph nodes, blood, and spleens. The SKOV-3 Luc tumor-bearing Hu-mice did not respond to pembrolizumab monotherapy. These tumors exhibited a high presence of tumor-infiltrating macrophages. Tumors in Hu-mice unresponsive to pembrolizumab showed a lower abundance of CD8+ T-cells, memory B cells, plasma cells, and a higher proportion of naïve M0 macrophages and mast cells compared to the PBS control. Furthermore, we identified 43 significantly enriched gene sets in these tumors. The differentially expressed genes (DEGs) were predominantly enriched in HDAC class I, RB1, KLF1/3, TCF21, MYD88, SMARCE1 target genes, and genes associated with epithelial-mesenchymal transition (EMT) and fibroblasts.

Conclusion: Our xenograft Hu-mouse model of OC provides a valuable tool for investigating the efficacy of IO drugs. The insights gained from this model offer potential avenues to explore mechanisms of resistance to PD-1/PD-L1 blockade in OC.

Citation Format: Sung Wan Kang, Ji-young Lee, Ok-Ju Kang, Yong-Man Kim, Eun Kyung Choi, Shin-Wha Lee. Transcriptome profiling and characterization of peritoneal metastasis ovarian cancer xenografts in humanized mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4187.
Abstract 4193: Digital PCR as a novel way to assess chimerism of humanized immune system mice
Authors: Smith Nicholas , Hansen Sarah , Livingston Robert S. , Smith Steve , Roesch Paula , MacBride Megan M.
Published: March 2024

Humanized immune system (HIS) mice contain human and murine immune cells. Analysis of chimerism in HIS mice is typically accomplished via flow cytometry, but this requires collecting a 75 μl blood sample and access to a flow cytometer. Repeated bleeding can negatively affect the health of HIS mice, limiting serial analysis. Digital PCR offers a novel method for chimerism analysis, which uses much smaller blood volumes and can be performed on clotted or frozen samples, sample types unsuitable for flow cytometry. A digital PCR assay directly comparing the presence of three human genes and one murine gene was developed. This assay was validated in the huNOG-EXL HIS mouse engrafted with CD34+ hematopoetic stem cells from 3 unique donors via blind comparison with chimerism data from flow cytometry. At 10 weeks post engraftment, the digital PCR assay showed excellent correlation for all three human genes against chimerism as measured by flow cytometry of the peripheral blood. This assay represents a new, user-friendly, rapid tool for the analysis of HIS mice and may permit serial chimerism measurement using 10 μL whole blood. This assay may be useful to investigate other mouse-human chimera models, including mice harboring functional human hepatocytes, tumors, and other cells.

Citation Format: Nicholas Smith, Sarah Hansen, Robert S. Livingston, Steve Smith, Paula Roesch, Megan M. MacBride. Digital PCR as a novel way to assess chimerism of humanized immune system mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4193.
Abstract 4273: Genetically engineered mesenchymal stromal cells degrade hyaluronic acid to disrupt the ECM and enhance cancer therapy outcomes
Authors: Browne Alice T. , Clements Miranda , Ju Wei , Kaplan Rosandra
Published: March 2024

The extracellular matrix (ECM) is a vital component of cancer pathophysiology. However, little is known about how to modulate the ECM for therapeutic benefit effectively. Hyaluronic acid (HA) is a polysaccharide component of the ECM with increased deposition during tissue injury or inflammation. HA in the tumor microenvironment (TME) has been linked to aggressive cancer progression. We have found enhanced ECM remodeling behavior linked to pre-metastatic niche formation and metastatic progression. To remodel this ECM-enriched microenvironment, we developed HA-targeting genetically engineered mesenchymal stromal cells (GEMesys) expressing hyaluronidase (Hyal), the enzyme responsible for HA degradation. We examined the impact of Hyal-GEMesys in osteosarcoma (F42010), rhabdomyosarcoma (M-3-9M), and pancreatic cancer (Panc02) syngeneic murine models. Hyal-GEMesys delivered to tumor-bearing mice homed to primary tumor sites and successfully degraded HA in the TME. The degradation of HA also resulted in a significant remodeling of collagen. T cells in Hyal-GEMesy treated tumors display an activated CD4+CD44+ phenotype with a reduction of LAG3+PD1+ exhaustion markers. Additionally, Hyal-GEMesy treatment results in a significant decrease in hypoxic regions within tumors and reorganization of the tumor vasculature to a more normalized phenotype, marked by diminished CD31 expression. Hyal-GEMesy treatment reduces tumor volumes in osteosarcoma, rhabdomyosarcoma, and pancreatic cancer models and enhances chemotherapeutic efficacy. These findings suggest that reorganizing the tumor ECM with Hyal-GEMesys holds the potential to dismantle the protective stroma of the tumor, which often shields malignant cells from therapeutic reach, and combining anti-cancer and anti-stroma agents can enhance anti-tumor efficacy and patient outcomes.

Citation Format: Alice T. Browne, Miranda Clements, Wei Ju, Rosandra Kaplan. Genetically engineered mesenchymal stromal cells degrade hyaluronic acid to disrupt the ECM and enhance cancer therapy outcomes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4273.
Abstract 429: A novel regulatory role of FLT3/ITD mutation in lipid metabolism of leukemia cells: The mechanism and therapeutic implications
Authors: Hu Yumin , Yin Feng , Zhao Mingyue , Lu Wenhua , Yu Tiantian
Published: March 2024

Internal tandem duplication in FMS-like tyrosine kinase 3 (FLT3/ITD), is a common type of activating mutation and frequently detected in AML. FLT3/ITD is associated with poor prognosis of AML. In this study, we investigated the regulation of FLT3/ITD mutation on sterol regulatory element-binding protein (SREBP) and the therapeutic vulnerabilities of lipid metabolism in FLT3/ITD leukemia. With the transcriptomics analysis we found that FLT3/ITD controlled lipid metabolism via the transcription factor SREBP. The analysis of TCGA_LAML dataset revealed that a gene signature involved in fatty acid and cholesterol metabolism, which is regulated by SREBP, was upregulated in FLT3/ITD patients compared with FLT3/wild-type patients. The upregulation of SREBP protein expression in FLT3/ITD leukemia was confirmed using a genetically engineered mouse model. We further demonstrated that FLT3/ITD regulates the protein degradation of SREBP through the PI3K/AKT-GSK3β axis. The metabolomics analysis further showed that FLT3/ITD primarily regulates glycerophospholipid synthesis, which contribute to the key structure lipid in the membrane, specifically, the cardiolipin. Moreover, pharmacologic inhibition of SREBP activation and its downstream enzyme fatty acid synthase (FASN) sensitized FLT3-ITD AMLs to the treatment of FLT3 inhibitor quizartinib. Collectively, our findings reveal a novel regulation of FLT3-ITD in metabolic reprogramming and indicate a targetable vulnerability in a subset of refractory leukemia.

Citation Format: Yumin Hu, Feng Yin, Mingyue Zhao, Wenhua Lu, Tiantian Yu. A novel regulatory role of FLT3/ITD mutation in lipid metabolism of leukemia cells: The mechanism and therapeutic implications [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 429.
Abstract 4292: Unraveling the interplay of aging, smoking, and mutation-driven clonal expansions in lung cancer evolution: A multifaceted approach
Authors: Briggs Amy N. , DeGregori James
Published: March 2024

Despite the well-established link between tobacco use and lung cancer, military personnel face additional risks due to heightened smoking rates and exposure to various environmental contaminants. Aging further amplifies susceptibility to lung cancer, contributing to elevated incidence rates among Veterans compared to non-Veterans. Our studies aim to elucidate the intricate relationship between aging, smoking, and mutation-driven clonal expansions in lung tissue, examining their impact on lung function and cancer evolution. Using cell culture and mouse models, we introduce mutations identified in human lung tissue into airway epithelial cells. Using CRISPR, base editing, and genetically engineered mouse models, we assess the effects on barrier function, cell differentiation, and gene expression. Ultimately, we are investigating the interaction between induced mutations, aging, and smoking, exploring how mutation-driven clonal expansions contribute to lung dysfunction and pre-malignant phenotypes, potentially forming a feedforward loop. This research addresses critical gaps in understanding the complex interplay of aging, smoking, and mutation-driven clonal expansions in lung cancer evolution. Findings have the potential to unveil novel insights into the development of lung dysfunction and malignancy, paving the way for safe and accessible interventions to reduce cancer risk and enhance lung health.

Citation Format: Amy N. Briggs, James DeGregori. Unraveling the interplay of aging, smoking, and mutation-driven clonal expansions in lung cancer evolution: A multifaceted approach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4292.
Abstract 4327: Development of bioluminescent biosensors to monitor the interaction betweenGSDMD and caspase-1 in living cells
Authors: Kelly Tynan
Published: March 2024

Gasdermin D (GSDMD) is the key executioner of pyroptosis, an inflammatory form of programmed cell death implicated in various inflammation-driven diseases, including cancer, heart failure and strokes. The interaction between GSDMD and caspase-1 (CASP1) orchestrates the critical pathway of GSDMD-mediated pyroptosis. During pyroptosis, pyroptosis stimuli activate CASP1, which subsequently binds to and cleave GSDMD between GSDMD’s N- and C-terminal domains. The free N-terminal domains oligomerize and translocate to the cell membrane, forming pores and releasing proinflammatory cytokines and causing cellular lysis. Key interaction sites have been identified for GSDMD recognition and engagement by CASP1; therefore, blocking functionally significant residues presents a new therapeutic strategy for inhibiting CASP1-induced GSDMD cleavage and pyroptosis. Currently, there is no small molecule capable of specifically disrupting the GSDMD and CASP1 interaction. In response, the ongoing pursuit of identifying potential inhibitors is a driving force for developing a biosensor capable of monitoring this interaction and their roles in downstream pyroptotic effects. In this study, we utilized the NanoLuc Binary Technology (NanoBiT) to construct several bioluminescent biosensors comprising two NanoLuc luciferase enzyme fragments (LgBiT and SmBiT) fused to GSDMD and CASP1, respectively, in various combinations. Further validation of these biosensors by luciferase assays in living cells identified a GSDMD-CASP1 biosensor with highest luciferase activity. This newly developed biosensor paves the way for high-throughput screens to identify novel small molecule inhibitors disrupting the GSDMD-CASP1 interplay. These small molecule inhibitors will effectively impede GSDMD-mediated pyroptosis, holding promise for novel therapies of various human diseases.

Citation Format: Tynan Kelly. Development of bioluminescent biosensors to monitor the interaction betweenGSDMD and caspase-1 in living cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4327.
Abstract 4355: Characterizing HRD in ovarian cancer: Insights from copy number signatures
Authors: Hawari Aliah , Tapinos Avraam , Kramer Claire J. , Gruber Andreas J. , Houlston Richard , Brenton James , Wedge David
Published: March 2024

Copy number changes are defining features in ovarian cancers. Two distinct methods by Steele et al. and Drews et al., published back-to-back in 2022, detail features and categories of copy number signatures. However, these methods have not been benchmarked for ovarian cancer. Mutational signatures are pivotal in understanding cancer biology and serve as predictive and prognostic biomarkers. This study aims to examine the landscape of copy number signatures to characterize the diversity of Homologous Recombination (HR) impairment within ovarian cancer. While assessing Homologous Recombination Deficiency (HRD) is crucial for targeted treatments, current HRD tests lack clarity. Using signature extraction tools SigProfilerExtractor and CINSignature, we analyzed whole-genome sequencing data (mean depth 100x) from 416 ovarian cases from Genomics England (GeL), employing both copy number signature methods. Among the signatures extracted, HRD signature CN17 from Steele et al. methodology was identified in 37% of the samples and primarily found in the high-grade serous ovarian cancer (HGSOC) subtype (77%). Additionally, higher exposure levels (median of 0.4 in n=154 compared to median of 0.29 in n=416) of Drews et al. methodology’s most complex HRD signature, CX3, was detected in samples exhibiting CN17 activity. This ongoing exploration of the copy number signatures landscape works towards identifying the spectrum of HR impairment, aiming to benchmark these two methods for a standardized diagnostic tool. This study contributes to our understanding of the mutational landscape of ovarian cancer and its potential implications for prevention and personalized treatment strategies.

Citation Format: Aliah Hawari, Avraam Tapinos, Claire J. Kramer, Andreas J. Gruber, Richard Houlston, James Brenton, David Wedge. Characterizing HRD in ovarian cancer: Insights from copy number signatures [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4355.