bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2901: Pdcd4 inhibits slug translation to suppress E-cadherin expression and invasion in colon tumor cells
Authors: Wang Qing , Zhu Jiang , Yang Hsin-Sheng 
Published: July 2021

Abstract
Programmed cell death 4 (Pdcd4) has been demonstrated to function as a tumor suppressor and protein translation inhibitor. We previously reported that knockdown of Pdcd4 down-regulated E-cadherin expression. E-cadherin is a key regulator for tumor cell invasion and metastasis, whose expression is controlled by transcription repressors Snail, Slug, ZEB1/2, and Twist. Both Slug and Snail have been shown to repress E-cadherin expression and contribute to tumor progression in various cancers including colon cancer. Here, we reported that knockdown of Pdcd4 increased Slug protein level but not SLUG mRNA level in colon tumor cells. Conversely, over-expression of Pdcd4 decreased Slug expression. Using sucrose gradient fractionation assays, Pdcd4 knockdown was found to increase the population of SLUG mRNA in the polysomal fractions. These results indicate that Pdcd4 translationally regulates Slug expression. To understand the mechanism by which Pdcd4 regulates Slug translation, the SLUG 5' untranslated region (5'UTR) was cloned and fused with luciferase reporter and named as 5'UTR-Slug-Luc. Knockdown of Pdcd4 significantly enhanced the translation of 5'UTR-Slug-Luc while ectopic expression of Pdcd4 repressed the translation of 5'UTR-Slug-Luc, suggesting that SLUG 5'UTR is an essential element for Pdcd4 to inhibit Slug translation. Moreover, cells treated with silvestrol, an inhibitor for translation initiation factor 4A (eIF4A), significantly suppressed Slug translation. In addition, ectopic expression of Pdcd4 inhibited Slug translation and thereby decreased E-cadherin expression. By contrast, Pdcd4(D418A), a mutant that does not bind with eIF4A, failed to suppress the expression of Slug and E-cadherin. These findings suggest that Pdcd4-inhibited Slug translation is through suppressing eIF4A. Furthermore, knockdown of Slug in Pdcd4 knockdown cells restored the E-cadherin expression and reversed the invasive capacity induced by Pdcd4 knockdown, indicating that up-regulation of Slug contributes to Pdcd4-knockdown enhanced invasion. Taken together, this study demonstrates that Pdcd4 inhibits translation of Slug to regulate E-cadherin expression and invasion in colon tumor cells.
Citation Format: Qing Wang, Jiang Zhu, Hsin-Sheng Yang. Pdcd4 inhibits slug translation to suppress E-cadherin expression and invasion in colon tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2901.
Abstract 2905: The relationship between peritoneal dissemination of gastric cancer & exosome
Authors: Kinoshita Kazuya 
Published: July 2021

Abstract
Introduction: In recent years, studies of exosomes have progressed rapidly, suggesting a connection to various physiological functions and pathogenesis. The exosomes are small extracellular vesicles with a diameter of 30 to 100 nm surrounded by lipid bilayers, and are attracting attention as a new cell-cell communication medium for carrying lipids, proteins, RNA, etc. in vivo. In addition, in exosomes released by cancer cells, it contains a large number of molecules related to angiogenesis and immunosuppression. It is believed to contribute to building microenvironments suitable for cancer cell growth and promoting cancer progression. Therefore, we focused on exosomes derived from gastric cancer cells, the action of gastric cancer cells, further constructed a gastric cancer peritoneal dissemination mouse model, the action of exosomes in gastric cancer peritoneal metastasis mechanism was examined in vitro, in vivo, respectively.
Method: Exosome Isolation Kit was used to extract exosomes from each gastric cancer cell line MKN-1, MKN-45, MKN-45 GFP. The determination of exosomes was carried out using Nano-drop®. Cell adhesion in exosome-treated and non-administered groups were analyzed by colony forming assay. Cell proliferation ability was analyzed using cell proliferation assay method. In vivo, we examined whether the degree of peritoneal dissemination was made using live cell imaging using fluorescent cells. MKN-45 GFP was intraperitoneally administered to BALB/c-nu mice. On days 0, 5, 10, 15, 20, groups were prepared in which 25 µg/500 µl of exosome was administered intraperitoneally and groups in which the same amount of PBS was administered intraperitoneally. In addition, MKN-45 GFP was subcutaneously injected into BALB/c-nu mice to create MKN-45 GFP tumors, which were divided into small horns and transplanted to the stomach walls of BALB/c-nu mice. In the same way as the previous method, we prepared a group in which 25 µg/500 µl exosome was intraperitoneally administered on days 0, 5, 10, 15, 20 and a group in which the same amount of PBS was intraperitoneally administered. We performed a visual comparison of transplanted cancer cells and peritoneal dissemination of cancer.
Results and Discussion: The results of the colony forming assay method suggest that exosomes derived from gastric cancer cells have the effect of promoting colony formation ability of cancer cells. We evaluate the results of peritoneal seeding model mice in this study, and further proceed with the analysis of miRNA extraction and analysis from exosomes derived from gastric cancer cells, and cell adhesion of cancer cells under high concentrations of exosomes.
Citation Format: Kazuya Kinoshita. The relationship between peritoneal dissemination of gastric cancer & exosome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2905.
Abstract 2939: Activation of NRF2 signaling accelerates development of small cell lung cancer in mice
Authors: Hamad Samera , Montgomery Stephanie , Bowman Brittany , Murphy Ryan , Randell Scott , Oliver Trudy , Hayes D. Neil , Major M. Ben , Weissman Bernard 
Published: July 2021

Abstract
Activating mutations in NRF2 frequently occur in human lung cancers, especially the E79Q mutation. However, how the activating mutation contributes to lung tumor development is not well understood. We used a new genetically engineered mouse model (GEMM), LSL-Nrf2E79Q/+ with Cre-inducible expression of this mutation within the endogenous Nrf2 locus, to understand its contribution to lung tumor development. We compared tumor development in p53fl/fl;p16fl/fl;LSL-Nrf2+/+ (WT) versus p53fl/fl;p16fl/fl;Nrf2E79Q/+ (Het) mice after intranasal instillation of Adenoviral Cre. While we did not observe a significant difference in lung adenocarcinoma (LUAC) between the Het and WT mice, the Het mice showed significantly higher frequencies of bronchial neuroendocrine tumors that resembled small cell lung carcinomas (SCLC) compared to WT. Additionally, the latency of SCLC lesions was lower in Het mice compared to WT. Surprisingly, LUACs in both groups were negative for NRF2 by IHC labeling despite recombination of the mutant Nrf2 allele. While all lesions in the WT and Het mice displayed positive ASCL1 and CGRp (NE markers) IHC labeling, only the SCLCs in Het mice expressed NRF2. This is the first study showing activation of Nrf2E79Q mutation drives development of small cell lung carcinomas. Interestingly, our data also suggest that the E79Q NRF2 activating mutation may inhibit the progression of LUAD.
Citation Format: Samera Hamad, Stephanie Montgomery, Brittany Bowman, Ryan Murphy, Scott Randell, Trudy Oliver, D. Neil Hayes, M. Ben Major, Bernard Weissman. Activation of NRF2 signaling accelerates development of small cell lung cancer in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2939.
Abstract 2942: Improved LAG-3 humanized knock-in mouse model for assessment of mono- and combination therapy strategies for cancer treatment
Authors: Li Huilin , Zhou Xiaofei , Li Dirui , Chromikova Veronika , Lin Qingcong 
Published: July 2021

Abstract
In recent years, immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. One of the potential therapeutic targets that seems increasingly attractive is LAG-3 (Lymphocyte activation gene 3, CD223), a human protein encoded by the LAG3 gene. LAG-3 can be found on activated T cells, NK cells, B cells and plasmacytoid DCs and serves as a negative regulator of immunity. Inhibition of LAG-3 enhances the antitumor effect of specific CD8+ T cells, which is an observation pursued by several pharmaceutical companies with their products in pre-clinical or early clinical development. Therefore, it is clear there is a need for suitable pre-clinical models able to accurately reflect the relevant physiological processes to evaluate the safety and efficacy of LAG3-targeted therapeutics. Biocytogen has generated a humanized LAG-3 mouse model for both in vitro functional validation and in vivo efficacy evaluation of anti-hLAG-3 antibodies. The targeting strategy is that exons 2~7 of mouse Lag3 gene which encode the extracellular domain are replaced by human LAG3 exons 2~7. After an introduction of this modification, human LAG-3 was detectable on Tregs in the mouse spleen and the anti-hLAG-3 antibodies and recombinant human FGL-1 protein associated well to the mouse splenocytes. Basal leukocyte subpopulations, including T/B/NK cells, DC, granulocytes, and monocytes/macrophages, were similar between humanized and wild-type mice. Additionally, anti-human LAG-3 antibodies partially blocked LAG-3/FGL-1 binding. Furthermore, using the MC38 tumor model, we show robust efficacy of anti-human LAG-3 antibodies in inhibiting tumor growth in vivo.In summary, LAG-3 humanized mice are a useful tool for in vivo efficacy evaluation of anti-human LAG-3 antibodies. Moreover, Biocytogen has also generated PD-1/PD-L1/LAG3 multi-gene humanized mice, in which blood cell composition, morphology and the levels of ALT, AST and other indicators were comparable to wild-type mice. This model is ideal to assess an increased therapeutic benefit in cancer treatment provided by combination therapies. Indeed, in our hands using the MC38 tumor model, the combination of anti-LAG-3 antibodies with anti-PD-1 (or anti-PD-L1) antibodies shows synergistic inhibitory effects , demonstrating that the PD-1/PD-L1/LAG3 humanized mice represent a powerful tool for preclinical assessment of in vivo efficacy of future therapeutics.
Citation Format: Huilin Li, Xiaofei Zhou, Dirui Li, Veronika Chromikova, Qingcong Lin. Improved LAG-3 humanized knock-in mouse model for assessment of mono- and combination therapy strategies for cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2942.
Abstract 295: Implementing fully automated kinase inhibitor characterization using a robotic system
Authors: Thomas Daniel A. , Fleming Tom A. , Bittner Martin-Immanuel 
Published: July 2021

Abstract
About 50 kinase inhibitors have been approved by the FDA for different indications so far. On the way from target validation to approval, the biochemical characterisation of a novel kinase inhibitor is a challenging, yet absolutely critical task. High resolution, kinetic molecular profiling can enable better data-driven decision making early on in the drug discovery process, not only saving time and resources, but also leading to superior molecular design. Arctoris developed a robotics-enabled process for fully automated kinase inhibitor characterisation, providing an unparalleled depth of data capture, going beyond the current state-of-the-art of biochemical assay setup. We validated our technology platform establishing assays against four members of the Janus Kinase family (JAK1, JAK2, JAK3, TYK2), profiling a set of JAK inhibitors. Of note, several JAK inhibitors with prior FDA approval for other indications entered clinical trials for COVID-19 treatment, making this target class particularly relevant for an in-depth study. Reagent validation, assay development, calibration, and optimization were expedited through systematic multifactorial experimental design, high density assay plate formats and versatile automated liquid handling. The Arctoris Ulysses platform affords 9 orders of magnitude range in liquid volume handling, with picolitre precision and contact-free digital dispensing for true, non-serial, independent experimentation. Fully automated protocols were optimized, validated, versioned, and explicitly encoded. Robust potency measurements of all inhibitors were established against each of the JAK targets, revealing molecules with distinct isoform selectivity. Designing and selecting molecules with specific activity profiles enables the fine tuning of pharmacology and the avoidance of unwanted off-target toxicity. Our unique platform, assay design, and deep expertise enabled the identification of molecules within the JAK inhibitor set that exhibit a range of kinetic properties. Our mechanistic analyses can help to elucidate the mode of inhibition (competitive, allosteric, synergistic etc.) as well as provide information pertaining to the kinetic selectivity that may be present but missed by focusing solely on potency.
Citation Format: Daniel A. Thomas, Tom A. Fleming, Martin-Immanuel Bittner. Implementing fully automated kinase inhibitor characterization using a robotic system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 295.
Abstract 2959: Establishment of KRAS-G12C inhibitor induced resistant tumor models enable the development of new generation KRAS-G12C inhibitors and combinatorial strategies
Authors: Liu Gaoxiang , Shi Wenting , Gu Qingyang , Ji Qunsheng 
Published: July 2021

Abstract
The KRAS (Ki-ras2 Kirsten rat sarcoma viral oncogene homolog) gene is one of the most popular oncogenes in the recent targeted therapy research. Activating KRAS mutations including G12C, G12D, etc are detected in around 25% of human cancers. The most common KRAS mutation is G12C, which comprises nearly 15% of lung adenocarcinoma, 8% of colorectal carcinoma and 4% of pancreatic adenocarcinoma. AMG-510 from Amgen and MRTX849 from Mirati Therapeutics both targeting KRASG12C mutant have shown encouraging activities in early clinical trials, especially shown a better overall response rate (ORR) and disease control rate (DCR) in KRASG12C mutant non-small cell lung cancer (NSCLC). However, acquired resistance to KRAS-G12C inhibitors will occur after prolonged treatment, which limits the effective evaluation in clinical trials. Various combinatorial strategies have been tried to overcome the resistance to KRAS-G12C inhibitors, including co-targeting vertical Ras signaling pathway and combining KRAS-G12C inhibitors with chemotherapeutics or immunotherapies. In order to facilitate the development of KRAS-G12C inhibitors, we have established an AMG510 resistant MIA PaCa-2 pancreatic adenocarcinoma CDX model and several colorectal carcinoma PDX models. These resistant models were derived from sensitive models carrying KRASG12C mutation, by prolonged treatment of AMG510 during several passages until a stable drug resistance phenotype occurred. To explore the resistant mechanisms, we performed Western blotting on downstream effectors ERK and found AMG510 produced less inhibition effect on ERK phosphorylation level in the resistant models. We are also developing more CDX and PDX models which are resistant to KRAS-G12C inhibitors. Therefore these models can be used to simulate acquired resistance to KRAS-G12C inhibitors after prolonged treatment in clinic, and provide a new tool to evaluate new generation of KRAS-G12C inhibitors as well as the combinatorial strategies with KRAS-G12C inhibitors.
Citation Format: Gaoxiang Liu, Wenting Shi, Qingyang Gu, Qunsheng Ji. Establishment of KRAS-G12C inhibitor induced resistant tumor models enable the development of new generation KRAS-G12C inhibitors and combinatorial strategies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2959.
Abstract 2963: A novel uterine leiomyosarcoma mouse model
Authors: Ng Chun Wai , Wong Kwong-Kwok 
Published: July 2021

Abstract
leiomyosarcoma is an extremely rare but clinically aggressive uterine cancer arising from the smooth muscle of the uterus. Each year, it is estimated to occur in 6 out of every 1,000,000 women in the United States. The average age at diagnosis is 51 and women with uterine leiomyosarcomas have a poor prognosis. Current therapies for uterine leiomyosarcoma are not very effective and the primary treatment of uterine leiomyosarcoma is surgery. Due to the intrinsic rarity of this disease, prospective randomized clinical trials examining the outcome in individuals with uterine leiomyosarcoma is limited. Moreover, a poor understanding of the pathogenesis of this disease is also a major knowledge gap to develop effective treatment strategies. Thus, a preclinical uterine leiomyosarcoma models that recapitulate the human disease is desperately needed to support clinical trial readiness. Since both p53 mutations and Pten homozygous deletion have been observed in 61% and 64% human uterine leiomyosarcomas respectively [3], we are generating genetic mouse models with Amhr2-Cre Ptenfl/fl p53R245Wfl/fl (homozygous p53 mutation), Amhr2-Cre Ptenfl/fl p53R245Wfl/+ (heterozgyous p53 mutation) and Amhr2-Cre Ptenfl/fl (control) genotypes. Our unpublished preliminary data showed that mouse with homozygous p53 mutation and homozygous deletion of Pten developed metastatic uterine leiomyosarcoma at 24 weeks of age with 100% penetrance. However, mouse with heterozygous p53 mutation and homozygous deletion of Pten did not develop uterine leiomyosarcoma at the age of 24 weeks. From the public available human uterine leiomyosarcoma RNAseq data, 80% of those tumors with p53 mutations had homozygous mutations. Previous mouse model with homozygous deletion of p53 gene and/or BRCA1 with Amhr2-Cre only had uterine leiomyosarcoma developed in approximately 50% of mice around 13 months without metastasis.
RNAseq and RPPA functional data of the uterine leiomyosarcomas from our novel mouse models are being generated for comparison with known genomic profiles of human uterine leiomyosarcomas. The RNAseq and RPPA functional proteomic data from comparing uterine tissues from homozygous and heterozygous p53 mutated mice provide insight in the understanding the development of uterine leiomyosarcoma and for future clinical trials.
Citation Format: Chun Wai Ng, Kwong-Kwok Wong. A novel uterine leiomyosarcoma mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2963.
Abstract 2973: Establishment of organoids and patient derived cancer cell lines from gastric cancer body fluids as preclinical models for personalized therapy
Authors: Kang Sun Kyoung , Bae Hyun Joo , Kwon Woo Sun , Kim Tae Soo , Lee Sujin , Cho Sang Woo , Chung Hyun Cheol , Rha Sun Young 
Published: July 2021

Abstract
Gastric cancer (GC), the second leading cause of cancer-related deaths worldwide, is especially prevalent in Asian countries. Despite advances in therapeutics, GC patients with peritoneal metastasis is frequent and when ascites has developed, the prognosis is very poor. Also, the number of anticancer drugs successfully marketed is rare in GC. Therefore, a faithfully in vitro model that can test various drugs and perform patient-specific personalized therapy is needed. We isolated cancer cells from ascites or pleural fluids of gastric cancer patients and established 19 patient-derived organoids and matched patient-derived cancer cell lines (PDCC). Organoid success rate was 60.7 % while PDCC was about 28.5 %. The time required to establish organoids was 1-2 months, while PDCC was 3-4 months. Organoids showed various growth characteristics and morphology, which reflects the clinical behavior of the patients including adenocarcinoma or signet ring cell carcinoma. In addition, drug-sensitive to each organoid and matched PDCC were identified using various chemotherapeutics and targeted agents. Then, patients' clinical information and comparative analysis were performed, suggesting the potential sensitive drug to each patient. Currently, the genetic information of each organoid is ongoing with WES/RNA Seq, and the sensitivity and comparative analysis of the drug will be performed. Therefore, our results provide a potential infrastructure for personalized therapy by comprehensive analysis of the patient's genomic data and organoid/PDCC model.
Citation Format: Sun Kyoung Kang, Hyun Joo Bae, Woo Sun Kwon, Tae Soo Kim, Sujin Lee, Sang Woo Cho, Hyun Cheol Chung, Sun Young Rha. Establishment of organoids and patient derived cancer cell lines from gastric cancer body fluids as preclinical models for personalized therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2973.