bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1140: Par-4 mediates EMT in response to TGF-β stimulation
Authors: Fabi François , Chaudhry Parvesh , Singh Mohan , Asselin Eric
Published: May 2015

Endometrial cancer is the most common cancer affecting the female genital tract; this disease also stands as the fourth most frequent cancer affecting occidental women. Endometrial cancer is generally well manageable; however, the high metastatic potential of endometrial tumors represents one of the major hurdles in the treatment of this disease. The epithelial to mesenchymal transition (EMT) has been considered for a long time as a central mechanism by which cancer cells acquire invasive abilities necessary for metastasis formation. Multiple regulatory networks dictate this complex process; however TGF-β has been shown to be one of the most important inductor of EMT in cancer cells. Still, the process by which TGF-β induces this transition has yet to be fully understood. Our study demonstrates that TGF-β upregulates the expression of Par-4, a tumor suppressor protein concomitantly with the onset of EMT. Four uterine cell lines (Hec-1-a, KLE, HeLa, HIESC), one ovarian cell line (SKOV-3) and one breast cell line (MCF7) were used in this study. We first investigated the effect of exogenous TGF-β treatment on these cell lines to determine its effect on Par-4 expression. We've observed that TGF-β increased Par-4 levels in every cell lines. Preliminary analysis determined that this regulation was made through both Smad4 and p65, which was confirmed by the use of siRNA. We've also demonstrated that this regulation was made at the transcriptional level by RT-qPCR. We then sought to confirm the effect of TGF-β on our cell lines and its effect on EMT induction. Our experiments demonstrated that TGF-β promotes EMT as suggested by the upregulation of multiple EMT markers. Transfections using Par-4 expression plasmids induced similar changes, indicating the involvement of Par-4 in TGF-β mediated EMT induction. We then proceeded to assess the effect of Par-4 knockdown concurrent with exogenous TGF-β stimulation. This experiment revealed that Par-4 knockdown reduced the ability of TGF-β to induce Snail expression, further demonstrating the importance of Par-4 in the process of TGF-β mediated EMT. To conclude the study, we sought to understand the effect of XIAP in this process. Our experiments uncovered that XIAP regulates full length Par-4 levels through the inhibition of its caspase-mediated cleavage. Furthermore, the inhibition of XIAP by siRNAs, and thus of Par-4 cleavage, resulted in the reduction of Par-4 EMT inducing capabilities. In conclusion, our study proposes a novel function of Par-4 as an inductor of EMT in multiple cell lines.

Citation Format: François Fabi, Parvesh Chaudhry, Mohan Singh, Eric Asselin. Par-4 mediates EMT in response to TGF-β stimulation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1140. doi:10.1158/1538-7445.AM2014-1140
Abstract 1157: Differential effects of aluminum exposure on epithelial and mesenchymal cells
Authors: AbdelMageed Manar A. , Foltopoulou Parthena , Betancur-Boissel Monica , McNiel Elizabeth A.
Published: May 2015

Introduction: Aluminium [Al(III)] is the third most abundant element as well as the most abundant metal in the Earth's crust. The human population is exposed to Al throughout daily life; in drinking water, food, via application of antiperspirants, use of antacids and vaccination. However, aluminum exposure has been linked to a variety of pathological disorders like anemia, osteomalacia , hepatic disorder, and neurological disorder. In addition, studies report that aluminum levels are higher in tumors, including breast cancers than in surrounding normal tissues. This suggests that aluminum accumulation may provide some selective advantage to the tumor.

Methods/Results:To determine how aluminum affects cells that reside in mammary tissue, we studied the in vitro effects of Al exposure on human mammary epithelial cells and mesenchymal cells. Cells used in our study included hTERT-immortalized human mammary epithelial cells (HMECs), the immortalized human mammary epithelial cell line (MCF10A), hTERT-immortalized reduction mammary fibroblasts (RMF/EG) and a dermal-derived human fibroblast cell line (MSU1.1). Using the MTT assay we found that AlCl3 and AlOH3 salts inhibit the growth of the mammary epithelial cells causing complete inhibition of proliferation at doses around 1mM and decreased proliferation was observed at doses as low as 12.8 uM. Surprisingly at these doses, Al salts caused dose-dependent increase in proliferation the mesenchymal cells. The proliferative effect of Al on mesenchymal cells was confirmed using clonogenic assay. Flow cytometric evaluation of cell cycle using PI/BrdU incorporation demonstrated that in MSU1.1 cells exposed to AlOH3 for 48 hrs, the percentage of cells in S phase of the cell cycle nearly doubled as compared to untreated cells (P <0.05). Similar results were seen with AlCl3 treatment of MSU1.1 and AlOH3/AlCl3 treatment of RMF/EG cells.

Conclusions: These data indicate that while Al salts induce dose dependent cytotoxicity in human epithelial cell lines, they induce proliferation of mesenchymal cells. The tumor microenvironment, including a proliferative stroma, is known to facilitate mammary carcinogenesis. Our data suggest that Al accumulation could promote the development of a permissive microenvironment. We are currently seeking to determine the mechanism for the differential effect of Al in cells and whether this effect influences transformation or carcinogenesis.

Citation Format: Manar A. AbdelMageed, Parthena Foltopoulou, Monica Betancur-Boissel, Elizabeth A. McNiel. Differential effects of aluminum exposure on epithelial and mesenchymal cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1157. doi:10.1158/1538-7445.AM2014-1157
Abstract 1174: VCAM-1 enhances immune evasion in a murine model of metastatic cervical cancer
Authors: Scrimieri Francesca , Bobanga Iuliana Dit , Eid Saada , Corn David J. , Barkauskas Deborah , Myers Jay Jay , Huang Alex Y.
Published: May 2015

Surface over-expression of Vascular Cell Adhesion Molecule-1 (VCAM-1) has recently been identified as a mechanism used by metastatic breast cancer cells to provide pro-survival advantages. It has been previously shown that the metastatic and immune-resistant mouse cervical cancer cell line, A17 has a significantly increased expression of VCAM-1 compared with the primary parental tumor cell line, TC1-P0. Using this metastatic tumor model, we first modulated the surface expression levels of VCAM-1 on A17 in vitro by using an shRNA knockdown approach. We then inoculated these cells intra-venously (iv) and subcutaneously (sq) into C57BL/6 background mice and athymic nude mice to interrogate how VCAM-1 expression affects surrounding immune cell interactions within the tumor microenvironment. To further characterize VCAM-1 dependent immune responses, we used intravital 2-photon laser-scanning microscopy (2P-LPS) to dynamically visualize immune-tumor cells interaction. We observed that VCAM-1 down-regulation reduces the primary tumor growth kinetics in C57BL/6 mice but exhibited similar growth kinetics in nude mice, suggesting that VCAM-1 levels are not responsible for the intrinsic primary tumor growth differences in vivo. Moreover, VCAM-1 down-regulated cell lines showed decreased lung metastasis in both immune-competent mice and athymic nude mice. Furthermore, the metastatic lung parenchyma in mice injected with the non-silencing shVCAM-1 control exhibited immune cell infiltrates with a predominance of M2 polarized macrophages and an altered cytokine production. This may be responsible for decreased susceptibility to immune surveillance. Together, our results demonstrate that tumor-associated VCAM-1 expression helps aggressive tumors circumvent effective immune surveillance, and may represent a target for the development of immune-mediated therapy in metastatic cervical cancer.

Citation Format: Francesca Scrimieri, Iuliana Dit Bobanga, Saada Eid, David J. Corn, Deborah Barkauskas, Jay Jay Myers, Alex Y. Huang. VCAM-1 enhances immune evasion in a murine model of metastatic cervical cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1174. doi:10.1158/1538-7445.AM2014-1174
Abstract 1176: Tumor derived peptide from a2 isoform of Vacuolar ATPase immunomodulates tumor associated neutrophils
Authors: Ibrahim Safaa A. , Amin Magdy , Beaman kenneth D.
Published: May 2015

It has been recently discovered that tumor associated neutrophils (TAN) develop N2 polarization similar to tumor associated macrophages (TAM). It is believed that the tumor microenvironment can provoke the wound repair response from TAN and TAM which in turn promotes tumor progression. Transforming growth factor- β (TGF-β) plays a key role in N2 polarization, however, other regulatory mechanisms are still unclear. a2 isoform Vacuolar ATPase (a2V) are highly expressed on tumors and macrophages. Recent evidence showed that a cleaved peptide from the N-terminal domain of a2V (a2NTD) is secreted in the microvesicles collected from various tumor cell lines. This peptide promotes the pro-tumorigenic characteristics in macrophages. Moreover, priming neutrophils with tumor conditioned media (TCM) collected from breast cancer cell lines promotes the pro-tumorigenic properties in neutrophils. In this study, we are evaluating the in vitro immune-modulatory effect of a2NTD on polymorphnuclear leukocytes (PMN) in order to explore the role of the a2V in the sterile inflammation associated with tumor progression. We isolated PMN from heparin anti-coagulated blood collected from healthy adult volunteers. TCM were collected from MDA-MB-231 breast cancer cell line. PMN were stimulated with either recombinant a2NTD or with TCM to simulate the tumor microenvironment. In both a2NTD and TCM cultures, distinctive morphological changes were revealed by microscopical examination and significant elevation of ROS levels were detected by flow cytometry (p-value <0.05). Moreover, we have observed an upregulation in PMN gene expression of CCL2, CXCL-1, CXCL-2, TNFα, VEGF, MMP-9, neutrophil elastase as well as a2V when it is cultured with either a2NTD or TCM using quantitative real time PCR. In accordance with Queen M., et al, flow cytometry showed delayed PMN apoptosis in cultures with TCM while upon inhibiting V-ATPase, PMN survival decreased significantly (p-value <0.05).This suggests that the delayed apoptosis observed in TCM primed PMN is mediated at least partially by V-ATPase. In addition, a2NTD increased significantly the PMN survival but to a lesser extent compared with TCM. Interestingly, we observed significant surface over-expression of a2V on PMN in both cultures using flow cytometry (p-value <0.05) and confocal microscopy. Our study demonstrates the potential immune-modulatory effect of tumor associated a2NTD on PMN which may indicate its involvement in tumor progression.

Citation Format: Safaa A. Ibrahim, Magdy Amin, kenneth D. Beaman. Tumor derived peptide from a2 isoform of Vacuolar ATPase immunomodulates tumor associated neutrophils. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1176. doi:10.1158/1538-7445.AM2014-1176
Abstract 1177: Pharmacological stimulation of DLL1-Notch signaling as an effective cancer immunotherapy
Authors: Biktasova Asel K. , Dudimah Fred D. , Uzhachenko Roman , Arasada Rajeswara Rao , Tchekneva Elena E. , Carbone David P. , Shanker Anil , Dikov Mikhail M.
Published: May 2015

Our data demonstrated that in cancer, expression of Notch ligands is selectively altered and Notch signaling in the hematopoietic compartment is attenuated and associated with impaired anti-tumor immunity caused by the aberrant T cell differentiation and function. Our important and therapeutically relevant finding is that stimulation of DLL1-mediated Notch signaling by systemic administration of soluble multivalent (clustered) DLL1 efficiently restores Notch signaling in the hematopoietic compartment. Such therapy strongly activates Notch downstream signaling and variably modulates expression of Notch receptors and ligands. Clustered DLL1 treatment results in significant enhancement of tumor antigen-specific T cell immune responses and memory, decreased proportion of regulatory T cells, remarkably increased tumor infiltration by T cells, attenuated tumor vascularization, and suppression of tumor growth. In an inducible model of lung tumor expressing L858R mutant EGFR in lung epithelium, clustered DLL1 elicited robust anti-tumor immune responses in concert with EGFR inhibition by erlotinib and produced remarkably improved progression-free survival. It is also likely that more efficient tumor killing and induction of T cell memory would significantly delay tumor progression/recurrence. Activation of Notch signaling by multivalent DLL1 in a panel of lung cancer cells in vitro did not stimulate cells proliferative of colony-forming potential, but rather demonstrated inhibitory effect in several cases. Pharmacological stimulation of Notch by multivalent DLL1 might represent an efficient strategy for enhancement of anti-tumor immunity and targeting multiple mechanisms of tumor growth. Reagents based on the multivalent forms of Notch ligands can be efficiently utilized for the therapeutic modulation of Notch signaling.

Citation Format: Asel K. Biktasova, Fred D. Dudimah, Roman Uzhachenko, Rajeswara Rao Arasada, Elena E. Tchekneva, David P. Carbone, Anil Shanker, Mikhail M. Dikov. Pharmacological stimulation of DLL1-Notch signaling as an effective cancer immunotherapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1177. doi:10.1158/1538-7445.AM2014-1177
Abstract 1179: Macrophage conditioned media increases the expression of a metastasis-associated oncogene, RhoC, and the migration of inflammatory breast cancer cells
Authors: Fournier Chelsea L. , Allen Steven G. , Chen Yu-Chih , Yoon Euisik , Merajver Sofia D.
Published: May 2015

Inflammatory breast cancer (IBC) is the most lethal form of breast cancer because it progresses rapidly and often presents with distant metastases at diagnosis. RhoC GTPases, known to play an important role in the movement of cells, are overexpressed in IBC tumor cells. The mechanism that causes this increase in RhoC expression is unknown. Tumor associated macrophages (TAMs) have been found to facilitate the movement and invasion of breast cancer. Therefore, as a component of the immune system attracted to sites of inflammation, we hypothesized that TAMs play a role in increasing RhoC expression in IBC cells, which consequently leads to IBC's severe migratory and metastatic capabilities.

The expression of RhoC increased in two different IBC cell lines, SUM149 and SUM190, in the presence of conditioned media (CM) from macrophage-differentiated U937 cells. This increase was not observed in either the normal-like MCF-10A cell line or the non-IBC MDA-MB-231 breast cancer cell line. From this observation, a novel microfluidic device allowed the study of the migratory phenotype of individual cells of the two IBC cell lines in response to standard chemoattractants as well as the macrophage CM. As expected, the presence of a serum gradient promoted the chemotaxis of IBC cells versus serum-free control. A CM gradient also increased the migration of IBC cells to a moderate degree. However, in the overlapping presence of CM without a gradient and serum with a gradient, the cells exhibiting an extreme migratory phenotype migrated roughly twice the distance of the serum gradient control. We believe the CM acts to “prime” the IBC cells in order to manifest an ultra-response to the serum chemoattractant. In both IBC cell lines stably-transfected with shRNA targeted to RhoC, we observed decreased migration when exposed to the CM migration conditions. Therefore, RhoC expression is necessary for this increase in migration.

Studies involving RhoC inhibitors are ongoing, but could yield promising therapies for the prevention of metastasis of IBC. Future studies will aim to identify which cytokines in the CM and which specific pathways are responsible for the increased RhoC expression and migration of IBC cells. By understanding the specific mechanism of TAMs' effects on IBC cells we hope to learn better how to control the lethal metastatic nature of inflammatory breast cancer.

Citation Format: Chelsea L. Fournier, Steven G. Allen, Yu-Chih Chen, Euisik Yoon, Sofia D. Merajver. Macrophage conditioned media increases the expression of a metastasis-associated oncogene, RhoC, and the migration of inflammatory breast cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1179. doi:10.1158/1538-7445.AM2014-1179
Abstract 1188: Primary human breast tumor explant platform for integrated profiling and target validation
Authors: Nevalaita Liina , Ala-Hongisto Hanna , Lehtivaara Maria , Heikkilä Päivi , Leidenius Marjut , Kovanen Panu , Monni Outi , Klefström Juha
Published: May 2015

Primary explant culture preserves three-dimensional architecture of tumor tissue, intra-tumoral heterogeneity and aspects of tumor microenvironment, including interactions between tumor cells and the adjacent tissue cells. For these reasons, it is believed that the explant cultures capture tumor-specific pathways and their complexities better than possibly any other in vitro or ex vivo tumor model. We are developing a primary human breast tumor explant platform allowing integration of rapid, small-scale genome profiling with validation of tumor specific targets. We show that the explants, processed to 100 uM fragments and cultured on a 3D matrix, contain both epithelial and stromal cells and maintain the viability for up to 12 days. To characterize the explant phenotype and similarity to the original tumor, we have examined explants and the original tumors side-by-side by immunohistochemistry (IHC), immunocytochemistry (ICC) and genome profiling. The biomarkers analyzed by IHC and/or ICC include hormone receptors, cytokines, epithelial and stromal cell markers as well as proliferation and apoptosis markers. A small-scale genome profiling analysis was performed with TruSeq Amplicon Cancer panel. Cancer-related missense mutations were identical in 60% of original tumor/ explant pairs and had minor differences in 40% of original tumor/ explant pairs. Compared to original tumors, proliferation was increased in explants but clear correlation in the level of proliferation between original tumor/ explant was observed. In conclusion, our preliminary findings suggest surprisingly similar genetic landscapes between breast tumor explants and the cognate primary tumors. Therefore, breast tumor explant platforms could predict well the efficacy of molecular targeted and personalized therapies.

Citation Format: Liina Nevalaita, Hanna Ala-Hongisto, Maria Lehtivaara, Päivi Heikkilä, Marjut Leidenius, Panu Kovanen, Outi Monni, Juha Klefström. Primary human breast tumor explant platform for integrated profiling and target validation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1188. doi:10.1158/1538-7445.AM2014-1188
Abstract 1211: Application of PDX models in mimic clinical trials for anticancer drug development
Authors: Chen Taiping , Hu Yan , Zhang Hui , Sun Xiaoqin
Published: May 2015

The utilization of patient derived xenograft (PDX) models has recently gained huge recognition in anticancer drug research and development. Based on molecular profiling the resemblance between patient tumor and PDX is significantly closer than that between patient tumor and traditional cell lines. Therefore, new initiatives are proposed to apply PDX models in in vivo target validation, clinical relevant MOA study, tumor addiction and heterogeneity characterization, sensitivity and resistance to chemotherapeutics and targeted therapeutics, and even mimic clinical trials for cancer type indication. In order to evaluate the efficacious and pharmacodynamic responses in PDX models and support the rationale for mimic clinical trials, we freshly established PDX models from the patients with colorectal (CRC), lung, pancreatic, gastric, liver cancers. The tumor take rate was very high for CRC and lung cancer patient, 90% and 70% respectively. Irinotecan and Cetuximab for colorectal PDX model, Docetaxel and Tarceva for lung PDX model were organized as mimic clinical trials. The high tumor take-rate (9 of 10 colorectal; 7 of 10 lung cancer) will ascertain pharmacologic significance when tested in mimic clinical trials. To illustrate the usefulness of this platform, we first evaluate the responders and non-responders based on efficacious trials. Then we will further continue with single dose for pharmacodynamic (PD) biomarker evaluation from selected drug targets or related pathway regulators. Efficacy results and corresponding PD biomarkers confirmed in this approach have potential to be used for cancer indication and patient stratification in later phase II clinical trials.

Citation Format: Taiping Chen, Yan Hu, Hui Zhang, Xiaoqin Sun. Application of PDX models in mimic clinical trials for anticancer drug development. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1211. doi:10.1158/1538-7445.AM2014-1211
Abstract 1218: Telomerase-specific GFP-expressing adenovirus enables fluorescence-guided surgery (FGS) for patient-derived orthotopic xenograft (PDOX) in nude mice
Authors: Yano Shuya , Hiroshima Yukihiko , Maawy Ali , Katz Matthew H.G. , Fleming Jason B. , Kishimoto Hiroyuki , Suetsugu Atsushi , Uehara Fuminari , Miwa Shinji , Tazawa Hiroshi , Bouvet Michael , Fujiwara Toshiyoshi , Hoffman Robert M.
Published: May 2015

We have previously developed the genetically-engineered GFP-expressing telomerase-specific oncolytic adenovirus (OBP-401) which selectively targets tumors. Our laboratory pioneered the patient-derived orthotopic xenografts (PDOX) model (Proc. Natl. Acad. Sci. USA 88, 9345-9349, 1991). In order to develop fluorescent-guided surgery (FGS) in the clinical setting, we used OBP-401 to label PDOX of pancreatic cancer in nude mice. OBP-401 (ip) effectively labeled pancreatic cancer PDOX in nude mouse models. GFP-expressing PDOX pancreatic tumors were readily resected using fluorescence-guided surgery (FGS). Our results suggest that OBP-401 therefore has clinical potential for labeling pancreatic cancer for FGS. This is particularly important in pancreatic cancer where positive margins result in most cases of standard surgery, leading to extremely low survival rates.

Citation Format: Shuya Yano, Yukihiko Hiroshima, Ali Maawy, Matthew H.G. Katz, Jason B. Fleming, Hiroyuki Kishimoto, Atsushi Suetsugu, Fuminari Uehara, Shinji Miwa, Hiroshi Tazawa, Michael Bouvet, Toshiyoshi Fujiwara, Robert M. Hoffman. Telomerase-specific GFP-expressing adenovirus enables fluorescence-guided surgery (FGS) for patient-derived orthotopic xenograft (PDOX) in nude mice. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1218. doi:10.1158/1538-7445.AM2014-1218
Abstract 1230: Efficacy of Salmonella typhimurium A1-R and anti-VEGF therapy on a patient-derived orthotopic xenograft (PDOX) pancreatic cancer model
Authors: Hiroshima Yukihiko , Zhao Ming , Katz Matthew H.G. , Fleming Jason B. , Sato Sho , Murakami Takashi , Yamamoto Mako , Uehara Fuminari , Miwa Shinji , Yano Shuya , Momiyama Masashi , Zhang Yong , Maawy Ali , Chishima Takashi , Tanaka Kuniya , Bouvet Michael , Endo Itaru , Hoffman Robert M.
Published: May 2015

We have previously developed the genetically-modified Salmonella typhimurium A1-R (A1-R) strain that selectively targets tumors and demonstrated that A1-R was able to eradicate primary and metastatic tumors in monotherapy in nude mouse models of various cancers including pancreatic cancer. The aim of this study was to examine the efficacy of A1-R treatment on VEGF-positive human pancreatic cancer in a patient derived orthotopic xenograft (PDOX) model in combination with anti-VEGF therapy. A VEGF-positive human pancreatic cancer cell line (MiaPaCa-2-GFP) and VEGF-positive pancreatic cancer PDOX were orthotopically implanted in nude mice. The nude mice were treated in the following groups: (1) gemcitabine (GEM) (80 mg/kg, ip, weekly, 4 weeks); (2) GEM (80 mg/kg, ip, weekly, 4 weeks) + Bevacizumab (Bev) (5 mg/kg, ip, twice a week, 4 weeks); (3) GEM (80 mg/kg, ip, weekly, 2 weeks) + Bev (5 mg/kg, ip, twice a week, 2 weeks) → A1-R (1.5x108 CFU/body, ip, weekly, 2 weeks); and (4) saline (vehicle/control, ip, weekly, 4 weeks). The mean tumor weight of each group in the MiaPaCa-2-GFP model was as follows: (1) GEM; 775.9 ± 273.8 mg; (2) GEM/Bev; 413.5 ± 108.3 mg; (3) GEM/Bev→A1-R; 257.5 ± 57.1 mg; and (4) Control; 2655.4 ± 583.9 mg. GEM/Bev→A1-R significantly reduced tumor weight compared to GEM/Bev treatment in the MiaPaCa-2-GFP model (p=0.022). The tumor weight of each group in the PDOX model was as follows: (1) GEM; 263.1 ± 129.1 mg, (2) GEM/Bev; 65.9 ± 41.9 mg, (3) GEM/Bev→A1-R; 21.9 ± 6.2 mg and (4) Control; 998.8 ± 377.7 mg. GEM/Bev→A1-R significantly reduced tumor weight compared to GEM/Bev treatment in the PDOX model (p=0.029). These results demonstrate that A1-R is effective on pancreatic cancer in combination with anti-VEGF, including the PDOX model indicating the clinical potential of this combination.

Citation Format: Yukihiko Hiroshima, Ming Zhao, Matthew H.G. Katz, Jason B. Fleming, Sho Sato, Takashi Murakami, Mako Yamamoto, Fuminari Uehara, Shinji Miwa, Shuya Yano, Masashi Momiyama, Yong Zhang, Ali Maawy, Takashi Chishima, Kuniya Tanaka, Michael Bouvet, Itaru Endo, Robert M. Hoffman. Efficacy of Salmonella typhimurium A1-R and anti-VEGF therapy on a patient-derived orthotopic xenograft (PDOX) pancreatic cancer model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1230. doi:10.1158/1538-7445.AM2014-1230
Abstract 1247: Assessment of the roles of prostaglandin E2 receptors in a rodent model of chemically induced esophageal carcinogenesis
Authors: Shi Ni , Chen Tong
Published: May 2015

Esophageal carcinogenesis is a multistage process characterized by morphological changes from normal esophagus to basal cell hyperplasia, dysplasia, carcinoma in situ and squamous cell carcinoma (SCC). Our laboratory has used a rodent model of N-nitrosomethylbenzylamine (NMBA)-induced esophageal SCC to investigate molecular carcinogenesis and identify putative chemopreventive agents. In our previous studies, we found that the expression of cyclooxygenase-2 and the production of prostaglandin E2 (PGE2) in rat esophageal epithelium were elevated in papillomatous lesions relative to precancerous and normal tissues. PGE2 exerts its cellular effect by binding to its cognate receptors. There are four subtypes of PGE2 receptors, EP1, EP2, EP3 and EP4, which are involved in carcinogenesis depending on the cell or tissue types. The overall objective of the current study was to assess the roles of PGE2 receptors in NMBA-induced rat esophageal tumorigenesis. F344 rats were injected subcutaneously with NMBA (0.30 mg/kg b.w.) three times per week for five weeks. One week after NMBA treatment, animals were randomized into five experimental groups and fed 300 ppm celcecoxib plus 50 ppm S,S'-1,4-phenylenebis(1,2-ethanediyl)bisisothiourea (PBIT) starting from week 6, 9, 12 , or 15, respectively, or 5% freeze-dried black raspberries (BRB) starting from week 6. Esophagi were collected at 29 weeks. Results of real-time PCR, western blot analysis and immunohistochemistry demonstrated a correlation between the upregulation of EP1, EP2, EP3 and EP4 and neoplastic progression in the rat esophagus. The expression of the PGE2 receptors in preneoplastic tissues and papillomas was significantly elevated when compared to normal tissues. Moreover, we observed that celecoxib + PBIT and 5% BRB significantly reduced EP2 expression. Our data suggest, therefore, that the production of PGE2 receptors by the esophageal epithelium is associated with the development of NMBA-induced esophageal tumorigenesis in rats, and EP2 antagonist may have chemopreventive potential in esophageal cancer. Research efforts are needed to elucidate the function of PGE2 receptors and related oncogenic pathways in esophageal SCC. (Supported by NIH/NCI R01 CA131073-01A1).

Citation Format: Ni Shi, Tong Chen. Assessment of the roles of prostaglandin E2 receptors in a rodent model of chemically induced esophageal carcinogenesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1247. doi:10.1158/1538-7445.AM2014-1247
Abstract 1263: Dietary patterns after prostate cancer diagnosis in relation to disease-specific and total mortality
Authors: Yang Meng , Kenfield Stacey A. , Blarigan Erin L. Van , Kasperzyk Julie L. , Sesso Howard D. , Ma Jing , Stampfer Meir , Chavarro Jorge E.
Published: May 2015

Objective: We investigated the relation of post-diagnostic dietary patterns with prostate cancer-specific and all-cause mortality.

Methods: 926 men participating in the Physicians' Healthy Study diagnosed with non-metastatic prostate cancer completed a food frequency questionnaire (FFQ) a median of 5.1 years after diagnosis, and were followed thereafter to assess mortality for a median of 9.9 years. Two dietary patterns, a Prudent and a Western pattern, were identified using principal component analysis. Multivariate Cox proportional hazards regression was used to estimate the relative hazard of prostate cancer-specific and all-cause mortality in relation to post-diagnostic dietary pattern scores. Models were adjusted for age at diagnosis, time between diagnosis and FFQ completion, energy intake, vigorous exercise, BMI, smoking status, and a modified D'Amico risk score.

Results: We identified 333 deaths, 56 due to prostate cancer, during 8,093 person-years of follow-up. The Prudent pattern was characterized by higher intake of vegetables, fruits, fish, legumes and whole grains, while the Western pattern was characterized by higher intake of processed and red meats, potatoes, high-fat dairy and refined grains. Men in the highest quartile (Q4) of the Western pattern had a higher risk of prostate cancer-specific death than men in the lowest quartile (Q1) (Hazard ratio [HR]: 2.39; 95% Confidence Interval [CI]: 0.95, 6.00; P for linear trend=0.03). The association between the Western pattern and prostate cancer-specific mortality appeared to be driven by intake of potatoes (HR[Q4 vs Q1]: 2.85; 95% CI: 1.06, 7.62; P for linear trend=0.01). In addition, the Western pattern was associated with higher all-cause mortality (HR[Q4 vs Q1]: 1.73; 95% CI: 1.20, 2.49; P for linear trend=0.005). A Prudent pattern after diagnosis was unrelated to prostate cancer-specific mortality but was associated with lower all-cause mortality (HR[Q4 vs Q1]: 0.60; 95% CI: 0.42, 0.88; P for linear trend=0.007).

Conclusions: A Western dietary pattern may increase risk of prostate cancer-specific and all-cause mortality, whereas a Prudent dietary pattern may decrease the risk of all-cause mortality, all among men diagnosed with localized prostate cancer.

Citation Format: Meng Yang, Stacey A. Kenfield, Erin L. Van Blarigan, Julie L. Kasperzyk, Howard D. Sesso, Jing Ma, Meir Stampfer, Jorge E. Chavarro. Dietary patterns after prostate cancer diagnosis in relation to disease-specific and total mortality. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1263. doi:10.1158/1538-7445.AM2014-1263
Abstract 1305: Basal level of FANCD2 monoubiquitination is required for the maintenance of a sufficient number of licensed-replication origins to fire at a normal rate
Authors: Jayabal Panneerselvam , Pickering Anna , Bing Han , Peiwen Fei
Published: May 2015

Normal DNA replication starts following the stepwise recruitment of replication initiators to assemble Mini-chromosome Maintenance (MCM) 2-7 protein complexes at an adequate amount of DNA replication origins. Under normal conditions, the monoubiquitination of Fanconi Anemia (FA) group D2 protein (FANCD2) occurs in each S-phase of cell cycle, which is the basal level of FANCD2 monoubiquitination. However, little is known regarding the roles of this basal level of monoubiquitinated FANCD2. Here, we report that monoubiquitnated FANCD2 in each S-phase of a given cell cycle can interact with replication origins and MCM3. In normally growing cells, the presence of non-monoubiquitinated FANCD2 or mutant MCM3 lacking AA 477-480 responsible for interacting with FANCD2 can lead to an insufficient amount of licensed origins ready for firing and, thereby, enlarged intervals between the fired origins. These results demonstrate that in normally cycling cells, the monoubiquitinated FANCD2 is required to maintain an enough number of licensed origins to initiate a normal DNA replication. This finding is the first to provide insights into how FANCD2 functions under normal conditions of cell cycle to maintain genome stability, as well as its resulting implications in the strategic improvement for the fight against human cancer. This study is funded by NIH RO1CA136532.

Citation Format: Panneerselvam Jayabal, Anna Pickering, Han Bing, Fei Peiwen. Basal level of FANCD2 monoubiquitination is required for the maintenance of a sufficient number of licensed-replication origins to fire at a normal rate. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1305. doi:10.1158/1538-7445.AM2014-1305
Abstract 1306: Synergistic function of a novel cell cycle regulator, Ecdysoneless with oncogenic Ras in the regulation of cell cycle and transformation
Authors: Bele Aditya , Mirza Sameer , Mir Riyaz , Mohibi Shakur , Band Hamid , Band Vimla
Published: May 2015

We have previously identified the mammalian ortholog of Drosophila ecdysoneless (Ecd) protein as a novel and essential regulator of Rb-E2F-dependent cell cycle progression. Consistent with role of Ecd in cell cycle, our recent studies show Ecd is overexpressed in breast cancer cell lines as well as in ductal carcinoma in situ and infiltrating ductal carcinomas of the breast. To explore the mechanism of Ecd overexpression and its correlation with oncogenesis, we overexpressed either Ecd alone, HRas-61L alone or both genes together in hTERT-immortalized human mammary epithelial cells (hMECs). These transfectants were then examined for their oncogenic properties. We observed while vector infected cells do not exhibit anchorage independence, all three transfectants showed increase in anchorage independent proliferation, particularly Ecd+Ras showed a significant increase in anchorage independence in comparison with either Ecd or Ras. Similarly, other oncogenic traits such as proliferation on matrigel, invasion and migration were dramatically increased when both genes were expressed in comparison with individual genes. Further analysis showed Ecd+Ras-expressing hMECs were unable to synchronize completely after growth factor deprivation and showed rapid progression into cell cycle, demonstrating synergy in altered cell cycle pathways in these cells. Most significantly, Ecd+Ras expressing hMECs were able to form tumors when implanted into mammary fat pads of NOD-SCID mice, whereas no tumors were observed with Ecd or Ras alone. These results demonstrate complete transformation of hMECs by overexpression of Ecd together with mutant Ras.

Considering the known oncogenic role of Ras in human cancer and the known role of Ecd in cell cycle, these data are highly significant and present a novel synergistic pathway for mammary cell transformation. Current studies are directed towards defining the mechanism of synergy between Ecd and Ras in cellular transformation.

Citation Format: Aditya Bele, Sameer Mirza, Riyaz Mir, Shakur Mohibi, Hamid Band, Vimla Band. Synergistic function of a novel cell cycle regulator, Ecdysoneless with oncogenic Ras in the regulation of cell cycle and transformation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1306. doi:10.1158/1538-7445.AM2014-1306
Abstract 1308: Functional inhibition of HSP90 induces G0/G1 arrest and downregulates thymidylate synthase in colorectal cancer
Authors: Nagaraju Ganji Purnachandra , Willingham Field F. , Woods Kevin E. , Sullivan Patrick , Landry Jerome C. , Diaz Roberto , El-Rayes Bassel F.
Published: May 2015

Purpose Objectives: Cell cycle progression and DNA synthesis are essential steps in cancer cell growth and resistance. Thymidylate synthase (TS) is a therapeutic target for 5FU. Ganetespib is a potent functional inhibitor of HSP90 currently under evaluation in clinical trials. We tested the hypothesis that HSP90 functional inhibition by ganetespib can inhibit cell cycle progression and downregulate TS levels in colorectal cell lines.

Methods: Two colorectal cancer (CRC) cell lines were used, HCT-116 and HT-29. Cells were either untreated (control) or treated with ganetespib at 50 nM for 24 hours. Western blot and Real time-PCR analyses were carried out to determine the effect of ganetespib on different signal molecules involved in cell cycle arrest and DNA synthesis. A subcutaneous xenograft mouse model was used to evaluate the in vivo effects of ganetespib. Pre and post ganetespib treatment tumor biopsies from patients with rectal cancer on a phase I trial of ganetespib were analyzed using RT-PCR.

Results: Treatment with ganetespib inhibited cyclin D1, pRb and E2F-1 at the transcriptional and translational level and induced p21, leading to G0/G1 cell cycle arrest. HSP90 knockdown inhibited E2F-1 and TS protein and mRNA levels in both cell lines. Arrest in the G0/G1 phase was associated with downregulation of the transcription factor E2F-1 and its target gene TS. Similar effects were observed in tumors from animals treated with ganetespib. Further, ganetespib treatment significantly inhibited the tumor growth. Inhibition of cyclin D1, Rb, E2F-1, TS and upregulation of p21 at transcriptional levels were observed in post treatment rectal tumor biopsies obtained from patients receiving ganetespib.

Conclusion: In this study, we present preclinical and clinical data to support the use of HSP90 inhibitors in colorectal cancer based on their ability to reduce expression of proteins important for DNA repair and cell cycle progression leading to cell cycle arrest and tumor shrinkage. Accordingly, combining HSP90 inhibitors with chemotherapy is a rational approach for future drug development in colorectal cancer.

Citation Format: Ganji Purnachandra Nagaraju, Field F. Willingham, Kevin E. Woods, Patrick Sullivan, Jerome C. Landry, Roberto Diaz, Bassel F. El-Rayes. Functional inhibition of HSP90 induces G0/G1 arrest and downregulates thymidylate synthase in colorectal cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1308. doi:10.1158/1538-7445.AM2014-1308
Abstract 1309: Identification of aurora kinase a as an unfavorable prognostic factor and potential treatment target for metastatic gastrointestinal stromal tumors
Authors: Yeh Chun-Nan , Yen Chueh-Chuan , Chen Yeng-Yang , Cheng Chi-Tung , Huang Shih-Chiang , Chang Ting-Wei , Yao Fang-Yi , Lin Yung-Chan , Wen Yao-Shan , Chiang Kun-Chun , Chen Jen-Shi , Yeh Ta-Sen , Tzeng Cheng-Hwai , Chao Ta-Chung , Fletcher Jonathan A.
Published: May 2015

Purpose: Although imatinib mesylate (IM) has revolutionized the management of gastrointestinal stromal tumors (GISTs), drug resistance remains a challenge. Previous studies have shown that the expression of aurora kinase A (AURKA) predicts recurrence in patients with primary surgically-resected GISTs. The current study aims to evaluate the significance of AURKA as an unfavorable prognostic marker for advanced GISTs, and provides evidence that AURKA could be a potential treatment target of GISTs.

Experimental Design: The prognostic significance of AURKA, along with other clinicopathological factors, was analyzed in a cohort of 99 IM-treated patients with advanced GISTs using immunohistochemistry. The potential use of an AURKA inhibitor as therapeutic agent against GISTs was also tested in GIST cell lines.

Results: Among 99 enrolled patients, poor performance status, large tumor size, drug response, and AURKA overexpression were independent poor prognostic factors for progression-free survival (PFS). For overall survival (OS), only large tumor size and AURKA overexpression were identified as independent unfavorable factors. In an in vitro study, MLN8237, an AURKA inhibitor, was demonstrated to inhibit growth of both IM-sensitive and IM-resistant GIST cells in a concentration-dependent manner. The inhibitory effect of MLN8237 on GIST cells could be attributed to the induction of G2/M arrest, apoptosis, and senescence, possibly through up-regulation of pro-apoptotic proteins.

Conclusions: Our study showed that AURAK is an independent poor prognostic factor for both PFS and OS in patients with advanced GISTs treated with IM. AURKA inhibitor could be used as therapeutic agent for both IM-sensitive and IM-resistant GISTs.

Citation Format: Chun-Nan Yeh, Chueh-Chuan Yen, Yeng-Yang Chen, Chi-Tung Cheng, Shih-Chiang Huang, Ting-Wei Chang, Fang-Yi Yao, Yung-Chan Lin, Yao-Shan Wen, Kun-Chun Chiang, Jen-Shi Chen, Ta-Sen Yeh, Cheng-Hwai Tzeng, Ta-Chung Chao, Jonathan A. Fletcher. Identification of aurora kinase a as an unfavorable prognostic factor and potential treatment target for metastatic gastrointestinal stromal tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1309. doi:10.1158/1538-7445.AM2014-1309
Abstract 131: C-kit induces epithelial-mesenchymal transition and contributes to salivary adenoid cystic cancer progression
Authors: Liang Xinhua , Tang Ya-ling , Jiang Jian , Fan Yun-long
Published: May 2015

Epithelial-mesenchymal transition (EMT) is associated with salivary adenoid cystic cancer (ACC) progression and metastasis. Here, we report that ectopic overexpression of c-kit in ACC cell lines is sufficient for acquisition of mesenchymal traits, enhanced cell invasion, along with stem cell properties defined by the presence of a CD133+/CD44+ cell subpopulation. c-kit positively regulated expression of known EMT inducers, also activating TGF-βto contribute to EMT. c-kit itself was induced by TGF-βin ACC cell lines and required for TGF-β-induced EMT. Xenograft experiments showed that c-kit cooperated with oncogenic Ras to promote tumorigenesis in vivo. Finally, in human specimens of ACC, we found that c-kit was abnormally overexpressed and correlated with the prognosis of ACC. Our findings define an important function for c-kit in ACC progression by orchestrating EMT, and they implicate this gene product as a marker of poor prognosis in this disease.

Citation Format: Xinhua Liang, Ya-ling Tang, Jian Jiang, Yun-long Fan. C-kit induces epithelial-mesenchymal transition and contributes to salivary adenoid cystic cancer progression. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 131. doi:10.1158/1538-7445.AM2014-131
Abstract 1322: Novel CDK4/6 inhibitors provide robust antitumor activity in a murine model of luminal breast cancer
Authors: Roberts Patrick J. , Darr David B. , Bisi John E. , Strum Jay C.
Published: May 2015

Introduction: Selective CDK4/6 inhibitors have emerged as attractive antineoplastic agents due to the importance of CDK4/6 activity in regulating cell proliferation. We have identified a series of orally available, potent and selective dual CDK4/6 inhibitors (G1T100182, G1T100183, G1T101551). Preclinical characterization of these compounds indicates that they inhibit CDK4 and CDK6 with an IC50 of 0.7-1.0 nM and 5-6 nM, respectively. In Rb competent tumor cells, these compounds potently inhibit Rb phosphorylation resulting in a G1 arrest. Here we assess the in vivo efficacy of these compounds in a genetically engineered mouse model of luminal breast cancer.

Methods: MMTV-Neu mice were housed and therapeutic response assessed in the UNC Lineberger Comprehensive Cancer Center's Mouse Phase I Unit (MP1U). Compounds were supplied by G1 Therapeutics, Inc. Tumors were serially assessed weekly using caliper measurements. Therapeutic intervention began once tumors reached 40-64mm3 and continued for 28 consecutive days. Tumor volume was calculated using the formula ((Width2) x Length)/2). All compounds were administered orally via medicated diets. RECIST criteria were used to assess objective response rates.

Results: Significant objective responses were noted in mice treated with G1T100182, G1T100183, G1T101551. Treatments produced modest reversible myelosuppression, but where otherwise well tolerated with no other clinical signs of toxicity or deaths associated with toxicity. A linear regression t-test was used to determine statistical significance of tumor volume changes over time. All treatment cohorts demonstrated statistically significant improvement when compared to un-treated mice; G1T100182, p<0.0001; G1T100183, p=0.0001; G1T101551, p<0.0001.

Conclusions: In summary, we have identified a series of orally active, potent, and selective small molecule inhibitors of CDK4/6 that may provide therapeutic benefit to cancer patients with tumors that have functional Rb protein.

Complete ResponsePartial ResponseStable DiseaseProgressive DiseaseORR % (CR+PR+SD/PD)Mean % Change in Tumor VolNo Treatment00090 (0/9)500G1T1001821510100 (7/0)-70G1T100183141185 (6/1)-67G1T1015511250100 (8/0)-40

Citation Format: Patrick J. Roberts, David B. Darr, John E. Bisi, Jay C. Strum. Novel CDK4/6 inhibitors provide robust antitumor activity in a murine model of luminal breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1322. doi:10.1158/1538-7445.AM2014-1322