bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1436: Cancer associated fibroblast dependency in a model of bladder cancer
Authors: Valentine Henkel , Satyal Uttam , Bukavina Laura , Uddin Hassan , Beyamin Yousttena , Arya Rhea , Abbosh Philip 
Published: March 2024

Abstract
Introduction: The relationship between genotype and phenotype in targeted therapy has proven to be crucial for most kinase inhibitors. In bladder cancer, the PI3K/AKT/mTOR pathway is widely activated by mutation but untargeted. Our study focuses on developing an immunocompetent, CRISPR-edited bladder cancer mouse model that mirrors common PI3K/AKT/mTOR mutations. We aim to establish genotype-effective kinase inhibitor pairings using in vitro CRISPR-edited organoids and Cancer Associated Fibroblasts (CAFs) to create a pro-tumorigenic environment in vivo.
Methods and Results: Urothelial cells were isolated from the bladder of Rosa26 Lox-Stop-Lox-Cas9/GFP transgenic mice to develop organoids. These organoids were co-edited for Trp53 and Rb1 KO, and further editing of the Pten gene resulted in a nine-fold increase in sensitivity to the kinase inhibitor ipatasertib. Despite successful engraftment into mouse bladder, these edited cells regressed before tumor formation, and intradermal injection did not yield subcutaneous tumors. An alternate model featuring a 9p21 deletion with Trp53 KO also displayed similar regression post-engraftment into bladder or skin. However, co-injection with skin-cancer-derived CAFs subcutaneously yielded palpable subcutaneous tumors that grew for 12 weeks. Enhancing orthotopic model fidelity, we established a BBN bladder-tumor-derived CAF line, leading to the formation of tumors with squamous differentiation upon intramural co-injection with edited organoids. These models displayed immune-excluded architecture and a predominance of M2 over M1 macrophages. Following our accomplishments in establishing bladder tumors, we aimed to enhance our model's adaptability by introducing common PI3K/AKT/mTOR mutations, specifically TSC1/TSC2 KO and Pik3ca hotspots, into our 9p21/Trp53 KO model. While TSC1/TSC2 KO lines exhibited elevated P-S6K signaling, they displayed resistance to Torin 1, Voxtalisib, and Everolimus—kinase inhibitors targeting mTORC1/2. In parallel, we employed CRISPR-mediated HDR to successfully introduce a Pik3ca H1047R hotspot into our 9p21/Trp53 KO model, as evidenced by increased Phosphorylation of AKT compared to wild-type 9p21/Trp53 KO cell lines.
Conclusions: Our research establishes the crucial role of CAFs in bladder tumor formation. Our now established customizable model of bladder cancer is suitable for direct targeting by kinase inhibitors while providing a platform for understanding the genotype-phenotype relationship in bladder cancer.
Citation Format: Henkel Valentine, Uttam Satyal, Laura Bukavina, Hassan Uddin, Yousttena Beyamin, Rhea Arya, Philip Abbosh. Cancer associated fibroblast dependency in a model of bladder cancer [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 1436.
Abstract 1465: Studying basal cell adaptation in the airways in response to chronic tobacco exposure
Authors: Peña David Osuna de la , Stoichkova Zornitsa , Przybilla Moritz Jakob , Percival Charlotte , Clarke Sarah E. , Gowers Kate H. , Campbell Peter J. , Janes Sam M. 
Published: March 2024

Abstract
Premalignant lesions in the airways are preceded by the accumulation of cells with a high mutational load, many of which carry driver mutations. Our previous work suggests this is a dynamic process: tobacco smoking increases the size of mutated clones, which contain shorter telomeres and higher Ki67, while smoking cessation appears to be associated with the expansion of clones with near-normal mutational burden and an overall reduction in Ki-67 expression. To understand how these long-term changes take place, we have performed ex vivo functional assays to quantify the competitive advantage imparted by smoke. We have then explored the transcriptomic landscape of these cultures to determine how differential smoke exposure modulates epithelial cell dynamics before and after smoking cessation.
Primary basal cells from bronchial explants were co-cultured following different regimes of exposure to cigarette smoke extract (CSE). We find that, upon acute exposure, pre-exposed cells have a ~20% higher chance of proliferating per week than smoke-naïve cells. To test this in a more physiological model, long-term epithelioid cultures were established with chronic exposure to low-dose CSE for months. As before, we observe that over time, pre-exposed cells outcompete the smoke-naïve, suggesting that smoke imparts a beneficial adaptation on re-exposed cells even at low doses. To elucidate this mechanism, we performed RNA sequencing of 48 different combinations of acute and chronic exposure to CSE. Genes were classified into distinct modules according to their regulation following exposure, re-exposure and cessation. Differential expression analysis and gene set enrichment analysis showed that metabolic pathways, including both nutrient and detoxification pathways, are predominantly enriched in these modules. In particular, following cessation, cells with the highest cumulative exposure to CSE displayed senescent-like features which are suppressed with chronic re-exposure. Further analysis and in vivo validation of these results will help elucidate how these changes affect the likelihood of premalignancy and may provide valuable targets for cancer prevention.
Citation Format: David Osuna de la Peña, Zornitsa Stoichkova, Moritz Jakob Przybilla, Charlotte Percival, Sarah E. Clarke, Kate H. Gowers, Peter J. Campbell, Sam M. Janes. Studying basal cell adaptation in the airways in response to chronic tobacco exposure [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 1465.
Abstract 1473: Exposure of arsenic promotes malignant stemness and induces bladder malignancy in preclinical models
Authors: Tyagi Bhawna , Vashishta Mohit , Tyagi Neha , Chandrasekaran Balaji , Shukla Vaibhav , Tyagi Ashish , Damodaran Chendil 
Published: March 2024

Abstract
Numerous epidemiological and scientific studies have consistently demonstrated that populations exposed to arsenic (As) concentrations ranging from &gt;10 ppb to 2500 ppb in their drinking water face an elevated risk of urogenital cancers, with a particular emphasis on bladder cancer (BCa). Hence, the goal of the study is to investigate the underlying mechanisms that trigger malignant transformation in the bladder using physiologically relevant arsenic concentrations observed in BCa patients. In our results, we observed significantly elevated levels of arsenic in the urine of BCa patients, ranging from 20 to 50 mg/L, in stark contrast to the levels observed in healthy controls (&gt;10 mg/L) and the recommended guidelines set by the Environmental Protection Agency (EPA) and Centers for Disease Control and Prevention (CDC). We used a median physiological concentration of arsenic (30 PPM) in drinking water-induced bladder hyperplasia in male and female mice over six months. Likewise, chronic exposure of healthy bladder epithelial cells (TRT-HU1) to similar arsenic concentrations (250nM:30 PPM) for 12 months resulted in malignant transformation, and arsenic-transformed cells (AsT) were capable of inducing tumors in xenografted and orthotopic models. Nonetheless, the molecular mechanism responsible for this malignancy remains to be elucidated. Our molecular analysis has pointed towards the activation of stem cells, notably ALDH1A1 (with a 50,000-fold increase), as a pivotal factor driving this transformation. Furthermore, our research has demonstrated that the activation of ALDH1A1 is contingent on the induction of Metal Response Element-Binding Transcription Factor-1 (MTF1). Consequently, silencing MTF1 inhibited the expression of ALDH1A1 and its associated malignant properties in As-transformed cells, strongly suggesting that MTF1 functions as the master regulator in As-induced bladder carcinogenesis. We have also observed similar molecular signatures (MTF1 and ALDH1A1 expression) in arsenic-exposed versus non-exposed mice and bladder cancer patients. In conclusion, our studies suggest that activation of stem cells is a critical step in arsenic-induced bladder carcinogenesis.
Citation Format: Bhawna Tyagi, Mohit Vashishta, Neha Tyagi, Balaji Chandrasekaran, Vaibhav Shukla, Ashish Tyagi, Chendil Damodaran. Exposure of arsenic promotes malignant stemness and induces bladder malignancy in preclinical models [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 1473.
Abstract 1548: Olfactomedin 4 deficiency promote de novo progression of prostate cancer in TRAMP mouse model
Authors: Li Hongzhen , Liu Wenli , Zhu Jianqiong , Chin Kyung , Rodgers Griffin P. 
Published: March 2024

Abstract
Prostate cancer is the most diagnosed solid tumor and the second leading cause of cancer-related death in American men. Olfactomedin (OLFM4) plays tumor suppressor roles and is associated with the initiation, growth, and clinical outcome of human prostate cancer. Olfm4-null mouse sporadically developed prostate epithelial neoplasia through up-regulated hedgehog signaling pathways. In this study, we have generated Olfm4+/+/GFP/TRAMP and Olfm4−/−/TRAMP mouse models to investigate Olfm4 gene biological functions underlying prostate cancer de novo progression. We have observed that Olfm4−/−/TRAMP mice developed more advanced prostate cancer at 47.6% (20/42) compared to Olfm4+/+/TRAMP at 11.9 % (5/42) and had poor survival compared to Olfm4+/+/TRAMP mice (P&lt;0.01). Histopathological and immunofluorescent staining revealed that tumor tissues containing more heterogeneous cells such as Ar+/Ck8+ epithelial or Syn+ neuroendocrinal cells or Vim+/Ck8+ epithelium mesenchymal transition cells in the primary tumors obtained from Olfm4−/−/TRAMP mouse. We found more tumor angiogenesis and metastases into lymph nodes, liver, lung, kidney, and soft tissues in Olfm4−/−/TRAMP mice. The accumulations of the dendritic cell population in primary tumor and lung metastasis tumors were detected. The primary tumor was sensitive to androgen deprivation therapy by using castration with both Olfm4+/+/GFP/TRAMP and Olfm4−/−/TRAMP mice. However, castration-resisted EMT tumor cells or expressing neuroendocrine marker cells regrew after castration 7-8 months in both Olfm4+/+/GFP/TRAMP and Olfm4−/−/TRAMP mice. Furthermore, we tested JQ1, a BET bromodomain inhibitor, as an epigenetic targeted therapy reagent and found that JQ1 significantly inhibited tumor cell growth of Olfm4−/−/TRAMP mouse tumor in the organoids culture. Taken together, we have provided novel evidence that Olfm4 plays a tumor-suppressing role during prostate cancer de novo progression.
Citation Format: Hongzhen Li, Wenli Liu, Jianqiong Zhu, Kyung Chin, Griffin P. Rodgers. Olfactomedin 4 deficiency promote de novo progression of prostate cancer in TRAMP 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 1548.
Abstract 1554: LIM Domain 7 (LMO7) splice variant influences prostate cancer biology
Authors: Abo Muthana Al , George Daniel J. , Wang Zefeng , Patierno Steven R. , Freedman Jennifer A. , Jiang Alice 
Published: March 2024

Abstract
LIM Domain 7 (LMO7) has been shown to participate in cell-cell junction formation through interaction with afadin and α-actinin. It has also been reported to collaborate with Rho kinase to regulate actin filament formation and to activate the Rho-myocardin-related transcription factor serum response factor pathway. Additionally, LMO7 itself may function as a transcription factor, regulating the expression of genes involved in Epithelial Mesenchymal Transition (EMT). Alternative splicing of LMO7 has the potential to modulate its function. Previously, we reported LMO7 as a target that is alternatively spliced in prostate cancer (PCa) between self-reported Black and White patients. In addition, by analyzing expression of LMO7 splice variants in The Cancer Genome Atlas (TCGA) data, we previously reported increased expression of a LMO7 splice variant skipping exon 12 in breast, lung and liver cancer compared with paired normal tissues. In the present study, we found that LMO7 is downregulated in metastatic PCa specimens within the Stand Up To Cancer cohort. To investigate the functional impact of expression of the LMO7 splice variant skipping exon 12 in PCa, we utilized CRISPR-Cas9 methodology to delete LMO7 exon 12 in PCa cells and assessed resulting alterations in PCa cell biology. The LMO7 exon 12 deleted PC3 PCa cells exhibited enhanced migratory potential compared with parental PCa cells. An Immunofluorescence (IF) assay showed weak staining of cell-cell junctions in LMO7 exon 12 deleted PCa cells compared with parental PCa cells. Moreover, IF staining showed retardation in f-actin in LMO7 exon 12 deleted PCa cells compared with parental PCa cells. As E-Cadherin is often inhibited during EMT, we assessed the level of E-Cadherin by western blot and real-time polymerase chain reaction (PCR). These analyses revealed that E-Cadherin protein as well as messenger RNA is suppressed in LMO7 exon 12 deleted PCa cells compared with parental PCa cells. These findings suggest a role for skipping of LMO7 exon 12 in disrupting PCa cell-cell junctions, down-regulating E-Cadherin in PCa and enhancing PCa cell migratory potential, consistent with EMT.
Citation Format: Muthana Al Abo, Daniel J. George, Zefeng Wang, Steven R. Patierno, Jennifer A. Freedman, Alice Jiang. LIM Domain 7 (LMO7) splice variant influences prostate cancer biology [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 1554.
Abstract 1566: Cancer metastasis and stemness: The metastasis-inducer MACC1 regulates LGR5 to promote cancer stem cell-like properties in colorectal cancer
Authors: Erdem Müge , Lee Kyung Hwan , Hardt Markus , Regan Joseph , Kobelt Dennis , Walther Wolfgang , Regenbrecht Christian , Stein Ulrike S. 
Published: March 2024

Abstract
Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. The high mortality is directly associated with metastatic disease which is thought to be initiated by colon cancer stem cells according to cancer stem cell (CSC) model. Consequently, early identification of those patients who are at high risk for metastasis is crucial for improved treatment and patient outcome. Metastasis-associated in colon cancer 1 (MACC1) is a novel prognostic biomarker for tumor progression and metastasis formation independent of tumor stage. We previously showed an involvement of MACC1 in cancer stemness in the mouse intestine of our transgenic mouse models. However, the expression of MACC1 in human CSCs and possible implications remain elusive. Here, we explored the molecular mechanisms by which MACC1 regulates stemness and CSC-associated invasive phenotype based on patient-derived 3D cell culture models (PD3D), patient-derived xenografts (PDX) and human CRC cell lines. We showed that CD44-enriched CSCs from PD3D models express significantly higher levels of MACC1 and display higher tumorigenicity in immunocompromised mice. Similarly, RNA sequencing performed on PD3D and PDX models demonstrated significantly increased MACC1 expression in ALDH1(+) CSCs, highlighting its involvement in cancer stemness. We further showed the correlation of MACC1 with CSC markers CD44, NANOG and LGR5 in PD3D models as well as established cell lines. Additionally, MACC1 increased stem cell gene expression, clonogenicity and sphere formation. Strikingly, we showed that MACC1 binds as a transcription factor to the LGR5 gene promoter uncovering the long-known CSC marker LGR5 as novel essential signaling mediator used by MACC1 to induce CSC-like properties in human CRC patients. Our in vitro findings were further substantiated by significant positive correlation of MACC1 and LGR5 in CRC cell lines as well as CRC patient tumors. Taken together, this study indicates that the metastasis-inducer MACC1 act as a cancer stem cell-associated marker. Interventional approaches targeting MACC1 would potentially improve further targeted therapies for colorectal cancer patients to eradicate CSCs, prevent cancer recurrence and distant metastasis formation.
Citation Format: Müge Erdem, Kyung Hwan Lee, Markus Hardt, Joseph Regan, Dennis Kobelt, Wolfgang Walther, Christian Regenbrecht, Ulrike S. Stein. Cancer metastasis and stemness: The metastasis-inducer MACC1 regulates LGR5 to promote cancer stem cell-like properties in colorectal cancer [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 1566.
Abstract 1593: Intercellular network in immune suppressive microenvironment of pancreatic cancer
Authors: Aoki Kazunori , Fukuda Hironori , Mizoguchi Yukihiro , Arai Kosuke 
Published: March 2024

Abstract
Despite constant efforts to improve treatment, the prognosis remains poor, with an overall survival rate of 6% (ranges from 2% to 9%) due to lack of efficient chemotherapy, radiotherapy, and targeted therapy. Immune checkpoint inhibitors (ICIs) has been reported to be effective in various solid cancers, such as melanoma, lung cancer, and renal cell carcinoma. However, pancreatic ductal adenocarcinoma (PDAC) is resistant against ICIs. The responsiveness of immune therapy is mainly determined by immune tumor microenvironment (TME) composed of tumor-infiltrating lymphocytes (TIL) and stromal cells. PDAC possesses unique TME, which is abundant of fibrosis, termed of desmoplasia, and the role of fibrosis in constructing immune suppressive TME remains unclear. First, in this study, to examine the immunological characteristics of TME, we constructed an integrated data base of TIL profiling, RNA-seq and whole exome seq using 31 fresh resected tissues of PDAC. An unsupervised clustering of based on numbers and percentages of 12 TIL types analyzed by flow cytometry showed that PDAC was divided into 2 types of cluster (myeloid cell-, T cell-dominant type), and the prognosis of myeloid type was significantly poorer than T cell-type. Myeloid type contained the high frequency of myeloid cell lineage including monocytes, macrophages and myeloid-derived suppressor cells (MDSC). Only MDSCs were significantly associated with poor prognosis among various immune cell types. Furthermore, gene enrichment analysis identified activated and suppressed pathways in each immune type, and in myeloid cell-dominant type, the immune-related pathways were significantly down-regulated. Then, to understand the characteristics of MDSCs infiltrated into pancreatic cancer tissues, single cell RNA-seq with surgical specimens was performed, and the analysis showed that a specific subtype of MDSCs infiltrated into cancer tissues. In addition, activation status of cancer-associated fibroblasts (CAFs) was related with MDSC recruitment and activation, indicating that the interaction between MDSCs and CAFs is crucial to create MDSC-rich TME. Inhibition of interaction between MDSCs and CAFs is expected to overcome immunosuppressive TME can be a therapy in PDAC.
Citation Format: Kazunori Aoki, Hironori Fukuda, Yukihiro Mizoguchi, Kosuke Arai. Intercellular network in immune suppressive microenvironment of pancreatic cancer [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 1593.
Abstract 1600: Interception of pro-tumorigenic glycan signaling in pancreatic cancer
Authors: Hsu Jasper , Song Hyemin , Peck Kristina , Bottomley Chelsea , Stamp McKenna , Okhovat Shira , Engle Dannielle D. 
Published: March 2024

Abstract
Pancreatic cancer is a deadly malignancy. We have setup a pipeline to interrogate cancer cell intrinsic and extrinsic mechanisms contributing to treatment response. Using a combination of mouse and human organoids models together with in vivo investigation, we have systematically dissected key signaling hubs driving pro-tumorigenic cancer cell intrinsic features as well as remodeling of the tumor microenvironment (TME). We found that the glycan epitope, CA19-9, drives pancreatic inflammation, cancer, and metastasis. CA19-9 drives pro-tumorigenic intrinsic features in part through CA19-9 modification of the secreted glycoprotein Fibulin 3. We have also discovered direct and indirect mechanisms through which CA19-9 causes remodeling of the TME. Specifically, CA19-9 elevation causes expansion of all cancer associated fibroblast (CAF) subtypes, including an increase in antigen presenting CAFs and resulting increase in regulatory T cells. Further, there are dramatic increases in tumor associated macrophages (TAMs) derived from both inflammatory monocytes as well as tissue resident macrophages. To delineate the mechanisms by which these TME changes are mediated, we use novel co-culture model incorporating macrophages, organoids, and fibroblasts (MOrF). Blocking CA19-9 signaling in vitro and in vivo reverses these TME alterations. These changes to the TME are mediated through indirect effectors as well as previously unknown CA19-9 modified proteins. Overall, we elucidate previously unexplored mechanisms driving pancreatic tumorigenesis while also uncovered vulnerabilities for therapeutic exploitation.
Citation Format: Jasper Hsu, Hyemin Song, Kristina Peck, Chelsea Bottomley, McKenna Stamp, Shira Okhovat, Dannielle D. Engle. Interception of pro-tumorigenic glycan signaling in pancreatic cancer [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 1600.