bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 5182: Activity and clinical relevance of autotaxin and lysophosphatidic acid pathways in high-grade serous carcinoma
Authors: Onallah Hadil , Trope Claes G , Falkenthal Thea E. Hetland , Davidson Ben , Reich Reuven 
Published: August 2018

Abstract
Lysophosphatidic acid (LPA) is a bioactive phospholipid with mitogenic and growth factor-like activities affecting cell invasion, cancer progression and drug resistance. It is produced mainly by Autotaxin and acts on six G protein-coupled receptors, LPAR1-6. LPA has recently been implicated as a growth factor present in ascites of ovarian cancer patients. However, mitogenic pathways stimulated by LPA via its receptors are still far uncharacterized. Here we show that three LPA receptors are involved in the progression of the malignancy by the activation of both AKT and ERK pathways. We analyzed a set of 155 samples of high grade serous ovarian carcinoma (HGSC) from the three different anatomic sites of the disease. Results show that LPAR2 mRNA was overexpressed in HGSC cells in effusions compared to solid lesions, with opposite findings for LPAR3 and LPAR6 mRNA and ATX protein that was found mainly in exosomes. LPAR3 levels were significantly higher in pre-chemotherapy effusions compared to post-chemotherapy specimens (p=0.025). Higher expression of LPAR1 (p=0.037), LPAR2 (p=0.025) and LPAR5 (p=0.021) was significantly associated with shorter overall survival. Furthermore, we combined 3D (spheroids) and 2D cell culture models with gene editing using the CRISPR/Cas9 method for LPAR2, LPAR3 and LPAR6 and tested the effects of their silencing in vitro using OVCAR3 and ES2 cell lines. The p-ERK/ERK ratio was significantly elevated in LPAR3KO OVCAR3 cells cultured both in 2D and 3D form. Yet, LPAR2KO OVCAR3 cells expressed low levels of p-ERK/ERK in the 3D form, suggesting that LPAR3 inhibits p-ERK activity downstream, while LPAR2 activates it. ES2 LPAR2KO cells expressed elevated levels of p-AKT/AKT ratio in both the 2D and 3D forms. OVCAR3 LPAR6KO had low p-AKT/AKT ratio when cultured in 2D, but high ratio in the 3D form. LPAR KO further inhibited ovarian cancer invasion and motility.Our results demonstrate, for the first time, significant changes in LPARs' mRNA levels and Autotaxin protein levels with changes in anatomic sites of the disease that correlate to clinic-pathological parameters. Our study identifies a specific molecular machinery triggered by LPA and its' receptors that modulate tumor and can serve as therapeutic targets in this malignancy.
Citation Format: Hadil Onallah, Claes G Trope, Thea E. Hetland Falkenthal, Ben Davidson, Reuven Reich. Activity and clinical relevance of autotaxin and lysophosphatidic acid pathways in high-grade serous carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5182.
Abstract 5191: Targeting CX3CR1 Impairs the reseeding and colonization of circulating tumor cells and decelerates metastatic progression
Authors: Qian Chen , Worrede-Mahdi Asurayya , Kaur Ramanpreet , Shen Fei , Salvino Joseph , Meucci Olimpia , Fatatis Alessandro 
Published: August 2018

Abstract
This study aims to understand the mechanisms and dynamics by which cancer cells, departing from existing metastases as circulating cancer cells (CTCs), further seed and colonize skeleton and soft tissues, expanding metastatic spreading and precipitating the clinical progression to terminal disease. We have previously shown that the chemokine receptor CX3CR1 is implicated in the metastatic seeding of breast cancer cells and that FX-68, a novel small-molecule antagonist for this receptor, effectively contains both number of lesions and total tumor burden in animal models of metastatic disease. Here we established that FX-68 impairs the reseeding of skeleton and soft tissue and that the CTCs unable to reseed and forced to remain in the blood eventually succumb to apoptotic death. The metastatic potential of CTCs was confirmed by reinoculation experiments as well as by forcefully mobilizing cancer cells from metastases back in the blood and assessing the number of additional lesions generated, in the presence and absence of FX-68. Furthermore, we found that prolonging the permanence of CTCs in the blood by targeting CX3CR1 with FX-68 improved exposure of cancer cells to the chemotherapy drugs doxorubicin or docetaxel significantly decreased tumor progression and extended overall survival. Finally, we found evidence that cancer cells seeding the skeleton despite the inhibition of CX3CR1 failed to develop into tumors, suggesting a role of CX3CR1 expression in the metastasis-initiating properties of breast cancer cells. In summary, our results strongly support developing CX3CR1 antagonists and promoting their clinical use, as this approach will provide novel and effective tools to contain the progression of metastatic disease in patients.
Citation Format: Chen Qian, Asurayya Worrede-Mahdi, Ramanpreet Kaur, Fei Shen, Joseph Salvino, Olimpia Meucci, Alessandro Fatatis. Targeting CX3CR1 Impairs the reseeding and colonization of circulating tumor cells and decelerates metastatic progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5191.
Abstract 5209: Overexpression of TGF-β in Smad4 deficient head and neck squamous cell carcinomas promotes myeloid cell infiltration associated with metastatic progression
Authors: Yu Jingjing , Hernandez Ariel , Raben David , Wang Xiao-Jing 
Published: August 2018

Abstract
Purpose of study: Transforming growth factor-β (TGF-β) has been shown to promote tumor progression when overexpressed and could be an important biomarker for head and neck squamous cell carcinomas (HNSCC) prognosis and treatment. Overexpression of TGF-β in tumor epithelia and stroma is observed in Smad4 deficient HNSCCs and is known to upregulate inflammation and angiogenesis. Our preliminary studies in Smad4 deficient HNSCC mice have revealed that inhibition of the TGF-β receptor (TGF-βR), specifically of the intracellular kinase domain, did not affect tumor growth in an immune compromised background but significantly decreased the number of metastatic lesions. We aim to elucidate the specific mechanisms by which TGF-β signaling promotes this metastatic phenotype in Smad4 deficient HNSCCs. We hypothesized that Smad4 deficient SCCs overexpress TGF-β to create an inflammatory microenvironment and promote angiogenesis to drive tumor progression in vivo.
Methods: Nude mice were injected subcutaneously in the flank with SCC cells derived from keratinocyte-specific Smad4 knockout mice and treated with either a TGF-βR inhibitor (n=5) or a vehicle control (n=6) once primary tumors reached 1mm3. Using immunofluorescence (IF) or immunohistochemistry (IHC), sections of the primary tumor were probed for leukocyte marker CD45, macrophage markers F4/80, iNOS and Arg1, myeloid cell markers CD11b and Ly6G and endothelial cell marker CD31.
Results: Smad4 deficient SCCs treated with the TGF-βR inhibitor showed a significant decrease in CD45+ leukocytes, with a specific decrease in CD11b+Ly6G+ cells compared to the vehicle control group. However, there was no difference in the total number of F4/80+ macrophages between TGF-βR inhibitor treated and vehicle control groups. There was also no significant difference in angiogenesis between these two groups as measured by the number of blood vessels/mm2 and the percentage area of the tumor covered by blood vessels.
Conclusions: Smad4 deficient SCC tumors treated with the TGF-βR inhibitor showed a significant decrease in myeloid cell populations, suggesting that overexpressed TGF-β plays a role in mediating inflammation in the tumor stromal environment. Treatment of SCC tumors with the TGF-βR inhibitor, however, did not show an affect on angiogenesis compared to the vehicle control.
Citation Format: Jingjing Yu, Ariel Hernandez, David Raben, Xiao-Jing Wang. Overexpression of TGF-β in Smad4 deficient head and neck squamous cell carcinomas promotes myeloid cell infiltration associated with metastatic progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5209.
Abstract 5212: The inhibitory effect of iron control on breast cancer cells in tumor microenvironment
Authors: Goto Wataru , Kashiwagi Shinichiro , Takada Koji , Asano Yuka , Takashima Tsutomu , Noda Satoru , Onoda Naoyoshi , Hirakawa Kosei , Ohira Masaichi 
Published: August 2018

Abstract
Background: Iron is an essential element for both normal and cancer cells, and it is well known that iron depletion leads to G1-S arrest and apoptosis. Iron depletion is also known to reduce serum hemoglobin and oxygen supply to the tissue, which may induce angiogenesis. On the other hand, it is reported that hypoxia mediates epithelial-mesenchymal transition (EMT) and cancer cell metastasis with angiogenesis. In addition, it is thought that antitumor autoimmune response relates to suppression of EMT, and we investigated previously it with clinical samples. In this study, we examined the mechanism of iron control therapy in breast cancer based on hypoxia, EMT and immune microenvironment.
Material and Methods: Human breast cancer cell lines MDA-MB-231 (triple-negative breast cancer), MCF-7 (luminal type) and OCUB-1 (HER2-enriched type), and iron chelator Deferoxamine (DFO) were used in the present study. The effect of proliferation and migration of breast cancer cells by DFO was determined using MTT assay and wound healing assay. We also examined the influence of cell cycle by DFO using flow cytometry. Furthermore, we investigated the relationship between iron depletion of breast cancer cells and hypoxia, EMT and immune microenvironment using RT-PCR. We produced subcutaneous xenografts of mice, and examined the change in tumor sizes by administration of DFO.
Results: The iron-depleted condition suppressed breast cancer cell proliferation and migration. In cell cycle analysis, DFO increased the population of the G0-G1 phase. In addition, iron depletion induced hypoxia and angiogenesis. Also, N-cadherin and PD-L1 expression of breast cancer cells were increased by iron-depleted condition. Subcutaneous tumors in the DFO administration group were suppressed tumor growth in vivo.
Conclusion: Iron control by DFO showed the effect of tumor suppression, and suggested the possibility of novel treatment for patients with breast cancer. In addition, this mechanism related to hypoxia, EMT and immune microenvironment.
Citation Format: Wataru Goto, Shinichiro Kashiwagi, Koji Takada, Yuka Asano, Tsutomu Takashima, Satoru Noda, Naoyoshi Onoda, Kosei Hirakawa, Masaichi Ohira. The inhibitory effect of iron control on breast cancer cells in tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5212.
Abstract 5215: Vitamin D receptor regulates intestinal barriers in colon cancer
Authors: Zhang Yong-guo , Lu Rong , Bakke Danika , Xia Yinglin , Sun Jun 
Published: August 2018

Abstract
Background Vitamin D and Vitamin D receptor (VDR) play important roles in the development of colon cancer. Tight junction structures are essential in intestinal barrier integrity, inflammation, and cancer. The disruption of tight junctions is a common manifestation of various diseases including cancers. Claudin-5 is a tight junction protein that is expressed in epithelia and endothelia and form paracellular barriers and pores that determine permeability. It is downregulated in colon cancer. Although VDR and Claudin-5 are all involved in colon cancer, it remains unclear whether they are closely related or function independently. Methods In the current study, we investigate the novel role of VDR in regulating Claudin-5, using whole body VDR knockout mice (VDR-/-) and intestinal epithelial VDR knockout mice (VDRΔIEC). In vitro, VDR-/- embryonic fibroblasts (MEF) cells, cultured human intestinal epithelial cells, organoids, and human colon cancer samples were used to determine the molecular mechanism. Results In intestinal samples of colon cancer patients, VDR expression is low, whereas the expression of Claudin-5 is also decreased. In the colon of VDR-/- mice and VDRΔIEC mice, deletion of VDR led to lower claudin-5 at the protein and mRNA levels. This observation was also confirmed by immunostaining of Claudin-5. In VDR-/- MEF cells, both Western blot and real time PCR revealed that VDR deletion led to lower protein and mRNA levels of claudin-5 in cells without any treatment. Vitamin D3 is known to increase VDR expression and activate VDR signaling. Protein and mRNA levels of Claudin-5 were significantly elevated in mice, mouse organoids, and human intestinal epithelial SKCO15 cells treated with 1, 25 vitamin D3. In contrast, knockdown of Claudin-5 using siRNA did not change the expression level of VDR protein in human colonic epithelial cells. Our data suggest that the Claudin-5 gene is a downstream target of the VDR signaling pathway. Conclusion Taken together, we show that VDR is important for the maintenance of physiological level of Claudin-5. This study also reveals a complex role for vitamin D/VDR regulation of intestinal barrier functions in colon cancer.
Citation Format: Yong-guo Zhang, Rong Lu, Danika Bakke, Yinglin Xia, Jun Sun. Vitamin D receptor regulates intestinal barriers in colon cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5215.
Abstract 5219: Effect of extracellular vesicles from gastric cancer cells on the morphologic and genetic changes of peritoneal mesothelial cells
Authors: Okuno Tomohisa , Yashiro Masakazu , Togano Shingo , Kuroda Kenji , Miki Yuichiro , Kasashima Hiroaki , Hirakawa Kosei , Ohira Masaichi 
Published: August 2018

Abstract
Background: Gastric cancer is a major cause of cancer death, particularly on the basis of peritoneal metastasis. Human scirrhous gastric carcinoma (SGC), diffusely infiltrating carcinoma, or Borrman type 4 also known as linitis plastica-type carcinoma is characterized by rapid cancer cell infiltration and proliferation accompanied by extensive stromal fibrosis. SGC account for about 10% of all gastric carcinomas, and carry an extremely worse prognosis than other types of gastric carcinoma, reflecting their frequent peritoneal metastasis. We previously reported that SGC cells (“seed”) might change the peritoneum to favorable environment, so-called pre-metastatic niche (“soil”), (Cancer 77:1668-75, 1996). Recently, it has been clarified that extracellular vesicles (EVs) play an important role for cell-cell interactions. In this study, we investigated the effect of EVs from SGC cells on the pre-metastatic niche formation of the peritoneum.
Methods: A SGC cell line, OCUM-2MD3, OCUM-12, KATO-III, gastric cancer cell line, MKN74, MKN45, and peritoneal mesothelial cells (PM cells) were used. PKH26-labeled EVs from OCUM-2MD3 cells were intravenously injected into nude mice, and the distribution of EVs was examined by a fluorescence microscope. The morphology of PM cells was investigated in the addiction of EVs from various gastric cancer cell lines using a phase-contrast microscope. And gene expression was examined by RT-PCR in the presence or absence of EVs from OCUM-2MD3. Clinical significance of EVs markers CD9 and CD63 was immunohistochemically evaluated using 63 human gastric cancer specimens.
Results: PKH26-labeled EVs were frequently found in the peritoneum, stomach and liver, but rare in lung and brain of mice. Peritoneal mesothelial cells uptake EVs of gastric cancer cells and change morphology from cobblestone shape to spindle shape in vitro. mRNA expression level of MMPs and integrins in PM cells was increased following the addiction of EVs, in compared with the control. The high expression of CD9 and CD63 was significantly correlated with distant metastasis.
Conclusion: EVs from gastric cancer cells might induce a pre-metastatic niche at peritoneum by the morphologic and genetic changes of mesothelial cells.
Citation Format: Tomohisa Okuno, Masakazu Yashiro, Shingo Togano, Kenji Kuroda, Yuichiro Miki, Hiroaki Kasashima, Kosei Hirakawa, Masaichi Ohira. Effect of extracellular vesicles from gastric cancer cells on the morphologic and genetic changes of peritoneal mesothelial cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5219.
Abstract 5234: Transcriptome profiling of single prostate cancer cells following androgen deprivation
Authors: Clark Ashlee K. , Lawrence Mitchell , Nim Hieu , Lister Natalie , Frydengerg Mark , Risbridger Gail , Taylor Renea 
Published: August 2018

Abstract
Androgen withdrawal is the standard of care for men with metastatic prostate cancer. While all patients initially respond, resistance is inevitable and lethal castration-resistant prostate cancer ensues. Using patient-derived xenografts (PDX) of localized tumors, we have identified a subpopulation of castration-tolerant prostate cancer cells that survive following castration. Identifying the unique biologic characteristics of these cells is essential in determining their role in tumor progression and potential to be targeted by therapeutic agents. To study the genomic features of castrate-tolerant cells, we enriched for prostate cancer cells from PDXs using FACS and subjected them to single-cell isolation and RNA seq. We efficiently captured and sequenced &gt;50 cells from pre- and post-castration PDXs using the Fluidigm C1 platform. Sequencing of isolated single cells was performed using the Illumina HiSeq in rapid mode with 50 bp fragment sequencing chemistry (3 million reads/cell). Multidimensional scaling showed that the response to castration is not uniform in all human cells. A unique gene set was identified in intact versus castrate-tolerant cells; we identified distinct changes in energy metabolism, including suppression of ATP production to aid cell survival. We also detected consistent upregulation of the retinoic acid signaling pathway, involving upregulation of CRABP2 and RARRES3 expression in castrate-tolerant cells. This is the first study to report on gene expression in single human prostate cells and revealed novel endocrine-related changes prior to and following androgen deprivation. Our data suggest that further and/or alternative hormone suppression may be effective in targeting castration-tolerant prostate cancer cells.
Citation Format: Ashlee K. Clark, Mitchell Lawrence, Hieu Nim, Natalie Lister, Mark Frydengerg, Gail Risbridger, Renea Taylor. Transcriptome profiling of single prostate cancer cells following androgen deprivation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5234.
Abstract 5242: NFĸB pathway activation is a key determinant of tamoxifen tolerance and recurrence in breast cancer
Authors: Kastrati Irida , Brovkovych Svitlana D. , Stender Joshua D. , Alarid Elaine T. , Frasor Jonna 
Published: August 2018

Abstract
Nearly 75% of breast tumors express estrogen receptor (ER) and will be treated with endocrine therapies, such as tamoxifen or aromatase inhibitors. Despite their proven success, it is estimated that up to 50% of tumors fail on endocrine therapy and recur as aggressive therapy-resistant tumors. Therefore, preventing recurrence remains a major clinical problem. One hypothesis is that recurrences are driven by cells that survive therapeutic intervention. This poorly understood population is referred to as minimal residual disease that consists of drug-tolerant cells capable of surviving by entering a state of negligible growth. In trying to model tamoxifen tolerance and minimal residual disease in vitro, we have utilized the clonogenic assay where ER+ breast cancer cells' clonal growth and survival in the presence of tamoxifen is examined. Tamoxifen-tolerant cells show activation of the pro-inflammatory NFĸB pathway measured by an NFĸB-reporter, elevated expression of bona-fide target genes, and enhanced nuclear localization of p65 and p50, two major transcription factors of the NFĸB pathway. Tamoxifen does not directly activate the NFĸB pathway, but rather cells with high NFĸB activity proliferate independently of tamoxifen despite retaining ER expression. Mechanistically, NFĸB-dependent ER phosphorylation at S305 residue may contribute to failure to respond to tamoxifen. More importantly blocking NFĸB with multiple NFĸB inhibitors is sufficient to eradicate this population of tamoxifen-tolerant cells, suggesting NFĸB is required and can be exploited for therapy. We find that dimethyl fumarate, an FDA-approved anti-inflammatory and immune-modulatory drug, which we have established as an effective NFĸB inhibitor in breast cancer cells, prevents recurrence modeled both in vitro and in vivo. Altogether this work shows a novel role for the NFĸB pathway in promoting a population of cells that are tamoxifen tolerant and capable of seeding recurrent breast cancer disease. Furthermore, therapeutic targeting by an NFĸB inhibitor such as dimethyl fumarate can be used to eradicate residual disease and prevent breast cancer recurrence.
Citation Format: Irida Kastrati, Svitlana D. Brovkovych, Joshua D. Stender, Elaine T. Alarid, Jonna Frasor. NFĸB pathway activation is a key determinant of tamoxifen tolerance and recurrence in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5242.