bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1961: Downregulation of proteasome activity promotes epithelial-mesenchymal transition
Authors: Garcia Daniel A. , Banno Asoka , Baarsel Eric D. Van , Metz Patrick J. , Widjaja Christella E. , Kim Stephanie H. , Bui Jack D. , Yang Jing , Chang John T.
Published: July 2017

The epithelial-mesenchymal transition (EMT) is a developmental program that is aberrantly activated in cancer cells, producing an invasive phenotype that can lead to metastases. Inducers of EMT are largely known and have been widely studied. However, the mechanisms that regulate the link between extracellular stimuli and EMT phenotypes remain poorly understood. Preliminary evidence from our laboratory suggests that downregulation of proteasome activity may be responsible, in part, for driving EMT. Using immortalized human mammary epithelial (HMLE) cells as a model, we show that (1) EMT is associated with decreased proteasome activity and increased polyubiquitinated substrates, (2) pharmacologic inhibition of proteasome activity leads to increased EMT phenotypes and functionality, and (3) pharmacologic inhibition of proteasome activity leads to increased EMT via stabilization of the TGF-β signaling pathway. Together, these data suggest that proteasome activity may be an unappreciated regulator of EMT.

Citation Format: Daniel A. Garcia, Asoka Banno, Eric D. Van Baarsel, Patrick J. Metz, Christella E. Widjaja, Stephanie H. Kim, Jack D. Bui, Jing Yang, John T. Chang. Downregulation of proteasome activity promotes epithelial-mesenchymal transition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1961. doi:10.1158/1538-7445.AM2017-1961
Abstract 1970: Glucose-regulated protein 94 is the novel progression biomarker in esophageal squamous cell carcinoma
Authors: Chang Yu-Jia , Huang Chien-Yu
Published: July 2017

Background

Esophageal cancer is a worldwide health problem with a very poor prognosis as most patients present very late when the disease is advanced and difficult to cure. It is urgent to figure out a diagnostic and therapeutic strategy. Glucose-regulated protein 94 (GRP94) has been found highly correlation with cancer progression. However, the role of GRP94 in the progression and metastasis of esophageal squamous cell carcinoma (ESCC) is still unclear.

Methods: We investigated the GRP94 expression level of ESCC cells and generated GRP94-KD cells by shRNA technique. The proliferation assay, migration, invasion assay were performed. The tissue array was performed to see the correlation of GRP94 and clinical outcome on ESCC. Mitochondrial bioenergetics were assessed using a Seahorse XF24 flux analyzer. The Transmission Electron microscopy was applied to see the structure of mitochondria.

Results: We found that ESCC specimen that expressed higher GRP94 showed the lower overall survival in tissue array results. The ESCC cells expressed high level of GRP94. Silencing GRP94 reduced the proliferation, migratory and invasion activity. Transmission Electron microscopy revealed the impaired mitochondrial in GRP94-KD cells. GRP94-KD cells also displayed reduced basal respiration, spare of respiratory capacity and ATP production. GRP94-KD caused the accumulation of oxidative damage. In molecular mechanism, we found that silencing GRP94 may cause a decrease COX2 expression and alter EMT expression pattern.

Conclusion

We found that silencing GRP94 in ESCC cells suppressed cancer growth and metastasis ability through COX-2 and EMT molecules expression. In addition, GRP94 may mediate the functional mitochondria in ESCC. GRP94 may be a new target to develop the therapeutic strategy for ESCC.

Citation Format: Yu-Jia Chang, Chien-Yu Huang. Glucose-regulated protein 94 is the novel progression biomarker in esophageal squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1970. doi:10.1158/1538-7445.AM2017-1970
Abstract 1980: Fusion of cancer and stromal cells imaged by color -coded imaging of metasasis
Authors: Nakamura Miki , Suetsugu Atsushi , Hasegawa Kousuke , Matsumoto Takuro , Aoki Hitomi , Kunisada Takahiro , Shimizu Masahito , Saji Shigetoyo , Moriwaki Hisataka , Hoffman Robert M.
Published: July 2017

We report here imaging of stroma during the metastatic process. RFP-EL4 lymphoma cells were injected subcutaneously in C57/BL6 GFP transgenic mice. Subcutaneous tumors were resected and immediately transplanted to the abdominal cavity of BALB/c nude mice. Metastases to the liver, perigastric lymph node, ascites, bone marrow and as well as the primary tumor were imaged. Metastases expressed GFP at low magnification. At higher magnification, yellow-remaining cancer cells resulting from fusion of GFP stromal cells and RFP cancer cells were observed. Metastasis contained fusion of caner and stromal cells which may be a feature of metastasis.

Citation Format: Miki Nakamura, Atsushi Suetsugu, Kousuke Hasegawa, Takuro Matsumoto, Hitomi Aoki, Takahiro Kunisada, Masahito Shimizu, Shigetoyo Saji, Hisataka Moriwaki, Robert M. Hoffman. Fusion of cancer and stromal cells imaged by color -coded imaging of metasasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1980. doi:10.1158/1538-7445.AM2017-1980
Abstract 1986: Determining the signaling pathway of epithelial-IKKα deletion-mediated symbiotic bacterial and fungal infection in carcinogenesis
Authors: Song Na-Young , Willette-Brown Jami , Zhu Feng , Hu Yinling
Published: July 2017

Bacteria and fungi, two major components of the microbiota, generally share niches and develop both antagonistic and symbiotic relationships, regulating the pathological impacts on the host. The epithelium is where the bacterial-fungal interaction occurs most abundantly, but the relationship between the epithelium, bacteria, and fungi on the pathogenesis, particularly tumorigenesis, is poorly understood. IKKα is one of the crucial factors regulating the homeostasis of squamous epithelial tissues. Recently, our lab has established a mouse model that develops esophageal squamous cell carcinomas associated with IKKα reduction, inflammation and chronic fungal infection. Cladosporium cladosporioides was a major type of fungi identified in this mouse model. Because IKKα deletion in the keratinocytes causes impaired skin barrier, we hypothesized that loss of epithelial IKKα may control fungal colonization through regulating the barrier integrity and inflammation. We generated IKKαf/f mice with inducible K15.Cre (IKKαf/f/K15.Cre) specifically expressed in keratinocytes in hair follicles which is considered as skin stem cells. After deleting IKKα in K15 cells in oral mucosa and skin, IKKαf/f/K15.Cre mice were orally inoculated with Cladosporium cladosporioides. We found that epithelial IKKα deletion increased bacterial colonization in oral mucosa and skin. Moreover, Cladosporium infection further promoted bacterial and fungal colonization in oral cavity and development of skin tumors. Taken together, our data suggest that loss of epithelial IKKα induces the bacterial-fungal symbiosis in oral mucosa, promoting skin tumors. This study will shed light on the importance of the epithelial-bacterial-fungal interaction in the pathogenesis, proposing epithelial IKKα as a novel regulator of the bacterial-fungal interaction.

Citation Format: Na-Young Song, Jami Willette-Brown, Feng Zhu, Yinling Hu. Determining the signaling pathway of epithelial-IKKα deletion-mediated symbiotic bacterial and fungal infection in carcinogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1986. doi:10.1158/1538-7445.AM2017-1986
Abstract 1991: Enhanced role of the extracellular matrix in ovarian cancer recurrence
Authors: Huang Zhiqing , Foster Brad , Grenier Carole , Sfakianos Gregory , Whitaker Regina , Berchuck Andrew , Murphy Susan K.
Published: July 2017

Purpose: Despite improvements in care and advancements in the understanding of ovarian cancer (OC) pathobiology and genetic alterations, the survival rate is disappointingly low when compared to that of other types of cancer. One factor contributing to the poor survival rate is the development of chemotherapeutic resistance and a high rate of recurrent tumor growth in the months and years following primary OC treatment. Our objective was to identify potential new therapeutic targets for prevention of recurrence through examination of changes in gene regulation that occur in recurrent versus matched primary tumors.

Procedures: We used 16 primary-recurrent tumor pairs from patients with stage III/IV serous epithelial OC from the Duke Gynecologic Oncology Tissue Bank. Illumina Infinium HumanMethylation450 BeadChips and Affymetrix Human Genome U133A arrays were used to quantify methylation and gene expression, respectively. Expression and methylation of POSTN and COL11A1 were analyzed using an independent OC dataset comprising 38 women with <3 years survival and 26 women with >7 years survival, 3 normal ovarian surface epithelium (OSE) and 2 fallopian tube fimbriae epithelium (FTFE) samples. siRNA knockdown of POSTN and COL11A1 in OC cells was followed by expression and proliferation assays.

Results: Paired student t tests showed a >2-fold difference for 13 of the 1,569 significantly differentially expressed genes, seven with increased expression in recurrent OC (POSTN, COL11A1, MMP1, MMP13, TNC, ASPN, and EPYC), and six with decreased expression (GATA6, PEG3, SST, MAOB, TSPAN8, and C7). Interestingly, all seven up-regulated genes are involved in extracellular matrix (ECM) functions, an important component of the tumor microenvironment. With an independent OC microarray dataset, we found elevated COL11A1 mRNA in OCs as compared to OSE and FTFE tissues (p<0.05). There are inverse correlations between COL11A1 expression and methylation at five promoter CG sites (R=-0.58 to -0.65, p<0.05). Immunohistochemistry showed higher expression of POSTN and COL11A1 in recurrent OC. Knockdown of POSTN and COL11A1 in OC cell lines led to significantly reduced proliferation (p<0.05).

Conclusion: Our findings indicate that the genes involved in extracellular matrix function that contribute to the composition and regulation of the tumor microenvironment play critical roles in OC recurrence, and may offer new therapeutic opportunities.

Citation Format: Zhiqing Huang, Brad Foster, Carole Grenier, Gregory Sfakianos, Regina Whitaker, Andrew Berchuck, Susan K. Murphy. Enhanced role of the extracellular matrix in ovarian cancer recurrence [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1991. doi:10.1158/1538-7445.AM2017-1991
Abstract 1993: Acidic tumor microenvironment stimulation of GPR4 alters cytoskeletal dynamics and migration of vascular endothelial cells
Authors: Krewson Elizabeth A. , Yang Li V. , Dong Lixue
Published: July 2017

The acidic tumor microenvironment results from aberrant vasculature, insufficient oxygen delivery and aerobic glycolysis of cancer cells. As cancer progresses, the acidic microenvironment can lead to structural changes of endothelial cells (ECs) resulting in increased vascular permeability which may increase metastasis. Extracellular acidification can activate cellular signaling molecules, including G-protein coupled receptor 4 (GPR4), which is prominently expressed in ECs. We have previously reported that acidic activation of GPR4 induces the transcription of several pro-inflammatory and ER-stress related genes in ECs. The purpose of the study is to identify the functional response of acidosis-induced GPR4 activity using Human Umbilical Vein Endothelial Cells (HUVECs) as a model system. The expression of GPR4 was overexpressed (HUVEC/GPR4) or knocked down (GPR4 shRNA) using several genetic constructs. HUVECs were treated with media buffered to pH 6.4 or to physiological pH 7.4. Permeability of a HUVEC cell monolayer was assessed by quantifying gap formation as one indicator. Cell migration was assessed through wound-healing assays. Cytoskeletal dynamics were also investigated using Rhodamine Phalloidin to investigate actin stress fiber formation and immunocytochemistry to investigate focal adhesion dynamics. Our results showed acidic pH induced GPR4 activation changed the cytoskeletal phenotype, decreased cellular migration, and proliferation in HUVECs compared to the physiological pH treatment. There was also a further increase in gap area of a HUVEC/GPR4 monolayer and formation of actin stress fibers in response to acidic conditions. Additionally, altering expression of phosphorylated paxillin and focal adhesion kinase were observed under acidosis/GPR4 mediated stress. In conclusion, the proton sensor GPR4 induces cytoskeletal variations, reduces cellular migration, and proliferation in response to an acidic tumor microenvironment.

Citation Format: Elizabeth A. Krewson, Li V. Yang, Lixue Dong. Acidic tumor microenvironment stimulation of GPR4 alters cytoskeletal dynamics and migration of vascular endothelial cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1993. doi:10.1158/1538-7445.AM2017-1993
Abstract 200: Long lasting inhibition of TGF-β receptor Type 1 inhibitor (TGF-β R1) for treatment of pancreatic cancer
Authors: Rodriguez-Aguayo Cristian , Bayraktar Emine , Shen Haifa , Lopez-Berestein Gabriel
Published: July 2017

Pancreatic cancer stroma is a high component of total tumor volume and activators of fibro-genesis such as Transforming growth factor-β (TGF-β) are abundantly secreted by pancreatic stellate cells (PSCs) to the tumor microenvironment. Aberrant TGF-β signaling pathways are associated with many human diseases, including bone diseases, immune-suppression, fibrosis, cancer progression and metastasis. However, the precise mechanism of this phenomenon in pancreatic cancer remains unclear. In this study we hypothesized that inhibition of TGF-β Type I receptor kinase (TGF-β R1) in pancreatic cancer and stellate cells regulates proliferation and fibrosis through the regulation of TGF-β R1 signaling pathway in PC cells, resulting in decreased migration, and decreased proliferation. We analyzed a TGF-β R1 data set of PC patients from the Cancer Genome Atlas. Furthermore, the analysis of a panel of pancreatic cancer cell lines showed that TGFR-B1 at mRNA and protein levels were higher in PC cells when compared with human pancreatic duct epithelial (HPDE) normal cells. In vitro cell viability, growth, cell-cycle progression, migration, invasion and apoptosis, as well as in vivo therapeutic effectiveness in murine xenograft models, were also assessed following the inhibition of TGF-β R1 in pancreatic cancer and stellate cells. The experimental validation identifies TGFR-β1 associated with PC survival. Significant inhibition of cell growth, invasion, migration, angiogenesis and fibro-genesis. Furthermore, treatment with LY-DMPC:DMPG-MSV inhibited growth of CAPAN-II tumors. These findings identify TGFR-β1 as a potential therapeutic target in pancreatic cancers expressing high levels of this oncogenic protein.

Note: This abstract was not presented at the meeting.

Citation Format: Cristian Rodriguez-Aguayo, Emine Bayraktar, Haifa Shen, Gabriel Lopez-Berestein. Long lasting inhibition of TGF-β receptor Type 1 inhibitor (TGF-β R1) for treatment of pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 200. doi:10.1158/1538-7445.AM2017-200
Abstract 2016: Novel dual cIAP1/XIAP antagonist ASTX660 activity in preclinical models of human papillomavirus(+) and (-) head and neck squamous cell carcinoma
Authors: Xiao Roy , An Yi , Derakhshan Adeeb , Chen Zhong , Schmitt Nicole C. , Waes Carter Van
Published: July 2017

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer with a five-year survival of ~50%. HNSCC are linked to human papillomavirus (HPV+) or tobacco carcinogenesis (HPV-). The Cancer Genome Atlas recently analyzed 279 HNSCC, revealing that 30% overexpress FADD (Fas-Associated Death Domain), with or without BIRC2/3 genes encoding cellular Inhibitor of Apoptosis Proteins 1/2 (cIAP1/2), which are critical components of the Tumor Necrosis Factor (TNF) Receptor signaling pathways that determine cell death or survival. The frequency of such mutations provides a window for potential therapeutics, as IAP antagonists have been shown to switch cancer cell TNFα signaling from being pro-survival to pro-apoptotic. We recently showed that birinapant, a second mitochondrial activator of caspases (SMAC) mimetic that promotes IAP degradation, sensitizes HNSCC to cell death by TNFα and eradicates tumors in combination with radiation in HPV- HNSCC models overexpressing FADD+/-BIRC2. ASTX660 (developed by Astex Pharmaceuticals) is a novel dual cIAP1/XIAP antagonist currently in clinical trials for treating advanced solid tumors and lymphomas. The objective of the present study is to determine the therapeutic effects of ASTX660 in HPV+/- HNSCC preclinical models. ASTX660 at nanomolar concentrations was found to potently inhibit cell proliferation (measured using XTT assays) and induce apoptosis (Annexin/7-AAD flow cytometry), and displayed combinatorial activity with TNFα, TRAIL, or cisplatin in multiple human HPV+/- HNSCC cell lines. Western blotting showed near complete degradation of cIAP1 expression at nanomolar concentrations in human HNSCC cell lines. Flow cytometry revealed that ASTX660 in combination with either TNFα or cisplatin reduced MHC-I expression and increased PD-L1 expression, suggesting that potential synergistic efficacy could be observed in combination with immune checkpoint inhibitors. Our results demonstrate that ASTX660 is a potential therapeutic agent for both HPV+/- HNSCC. Experiments evaluating the anti-tumor effects of ASTX660 as a monotherapy and in combination with radiation, cisplatin, and anti-PD-1 therapies are ongoing, using both human HNSCC xenograft and syngeneic mouse oral cancer (MOC) models. Supported by NIDCD intramural projects (ZIA-DC-000016, 73 and 74).

Citation Format: Roy Xiao, Yi An, Adeeb Derakhshan, Zhong Chen, Nicole C. Schmitt, Carter Van Waes. Novel dual cIAP1/XIAP antagonist ASTX660 activity in preclinical models of human papillomavirus(+) and (-) head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2016. doi:10.1158/1538-7445.AM2017-2016
Abstract 202: Comprehensive spatial mapping by MALDI imaging mass spectrometry of the N-glycan tissue glycome and database generation for eighteen tumor types
Authors: Drake Richard R. , Talbot Kacey , Norris-Caneda Kim , Bruner Evelyn , Angel Peggi M.
Published: July 2017

Glycoproteins account for approximately 80% of the proteins located at the cell surface and in the extracellular environment, and serve as binding ligands for cell adhesion, extracellular matrix molecules, signaling receptors, immune cells, lectins and pathogens. Alterations and changes in cell surface glycosylation during tumorigenesis are well documented, including the major N-linked glycan class of glycosylated proteins. We have recently developed a MALDI imaging mass spectrometry (MALDI-IMS) method to spatially profile N-linked glycans in frozen and formalin-fixed paraffin-embedded (FFPE) tissue sections and tissue microarrays (TMAs). In order to facilitate method development and maximize glycome determinations for many cancer types, we have generated two custom TMAs comprised of multiple tissue core pairs of non-tumor and tumor regions representing eighteen different tumor types (pancreatic, colon, prostate, breast, lung, melanoma, sarcoma, head/neck, kidney, liver, glioma, ovarian, thyroid, uterine, cervical, testicular, gastric, bladder). Tissues are incubated with a molecular coating of peptide N-glycosidase, and released N-glycans are detected directly using MALDI-FTICR imaging, linked directly with tissue histopathology. The method is able to simultaneously identify and distinguish 50 or more components of the N-glycome on a single slide. The approach allows comparison of the similarities and differences in N-glycome compositions across each tumor tissue type, as well determine the relative abundance of each individual glycan across all tumor types. For example, an increase in high mannose glycans is common to many tumor types. From the TMA data, this glycan class is consistently elevated for colon, prostate, lung, breast and bladder cancers, while the other tumor types are variable. Differences in branching complexity, bisecting N-acetylglucs0amine, and the degree of fucosylation and sialylation are also readily evaluable. Additionally, data from each of the TMA core pairs is being compared systematically to the N-glycans detected in the source FFPE blocks. The goal is to generate an extensible reference database of expected N-glycans for each tumor tissue type. This will also provide a framework to expand to other classes of glycans, and complementary glycan data generated by other methods on the same TMA cores.

Citation Format: Richard R. Drake, Kacey Talbot, Kim Norris-Caneda, Evelyn Bruner, Peggi M. Angel. Comprehensive spatial mapping by MALDI imaging mass spectrometry of the N-glycan tissue glycome and database generation for eighteen tumor types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 202. doi:10.1158/1538-7445.AM2017-202
Abstract 2028: PDE3A modulation for cancer therapy
Authors: Wu Xiaoyun , Lewis Timothy , Waal Luc de , Gao Galen , Zhang Jian , Schenone Monica , Garvie Colin , Diamond Brett , Lorrey Selena , Cherniack Andrew , Corsello Steven , Burgin Alex , Golub Todd , Schreiber Stuart , Meyerson Matthew , Greulich Heidi
Published: July 2017

In a differential cytotoxicity screen, we identified a novel small molecule modulator of phosphodiesterase 3A (PDE3A) that kills cancer cells expressing elevated levels of PDE3A and SLFN12 (de Waal, Nat Chem Biol, 2016). Treatment with this cell-selective cytotoxic small molecule, DNMDP, induces complex formation between PDE3A and SLFN12, resulting in apoptosis. Inhibition of PDE3A enzymatic activity is not sufficient for cancer cell killing, and expression of both PDE3A and SLFN12 are required. Although the mechanism of signaling to the apoptosis machinery remains unclear, we examined more closely the role of the PDE3A-SLFN12 complex in cancer cell killing mediated by DNMDP. We found that cancer cell lines made resistant to DNMDP by persistent exposure downregulated SLFN12 expression and that re-expression of SLFN12 was sufficient to restore sensitivity. Furthermore, ectopic expression of PDE3A and SLFN12 are sufficient to sensitize cancer cells to DNMDP. These data underscore the tight correlation of PDE3A-SLFN12 complex formation and cancer cell killing mediated by DNMDP.

Citation Format: Xiaoyun Wu, Timothy Lewis, Luc de Waal, Galen Gao, Jian Zhang, Monica Schenone, Colin Garvie, Brett Diamond, Selena Lorrey, Andrew Cherniack, Steven Corsello, Alex Burgin, Todd Golub, Stuart Schreiber, Matthew Meyerson, Heidi Greulich. PDE3A modulation for cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2028. doi:10.1158/1538-7445.AM2017-2028
Abstract 2055: Therapeutic resistance to BET bromodomain inhibition in prostate cancer
Authors: Engelke Carl G. , Malik Rohit , Kregel Steven , Asangani Irfan A. , Wilder-Romans Kari , Jiang Xia , Cao Xuhong , Speers Corey , Chinnaiyan Arul M.
Published: July 2017

Prostate cancer is the most common cancer among men and a leading cause of cancer-related death in North America. Current therapies include radical prostatectomy and radiotherapy for localized disease, and androgen deprivation therapy (i.e. surgical or medical castration) for metastatic disease. Recently, we described the use of inhibitors of bromodomain and extraterminal (BET) proteins for the treatment of castration-resistant prostate cancer (CRPC), which have since undergone investigation in clinical trials. In anticipation of patients refractory to treatment with BET inhibitors, we explored the development of resistance to a clinical-grade BET inhibitor in four cell line models—VCaP, LNCaP, LNCaP-AR, and 22Rv1—by serially passaging cells in increasing concentrations of drug with matched controls in DMSO. All resistance models displayed several-fold increased IC50 values relative to control in in vitro cell viability assays. Additionally, we have modeled resistance to BET inhibition in vivo by serially passaging cell line- and patient-derived xenografts in animals treated with BET inhibition. Interrogating these models through traditional molecular techniques and next-generation sequencing, we discovered several putative mechanisms of resistance to BET inhibition that we are currently validating in our laboratory.

Note: This abstract was not presented at the meeting.

Citation Format: Carl G. Engelke, Rohit Malik, Steven Kregel, Irfan A. Asangani, Kari Wilder-Romans, Xia Jiang, Xuhong Cao, Corey Speers, Arul M. Chinnaiyan. Therapeutic resistance to BET bromodomain inhibition in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2055. doi:10.1158/1538-7445.AM2017-2055
Abstract 2058: Co-treatment of NVP-BSK805 highly sensitizes drug-resistant cancer cells by increasing P-gp inhibition
Authors: Park Yu Jin , Cheon Ji Hyun , Son Ji Yeon , Yoon Sung Pil , Kim Hyung Sik
Published: July 2017

The high expression of P-glycoprotein (P-gp) is consistently observed in multidrug resistance (MDR) cancer cells. The purpose of our study is to identify conditions that could increase the sensitivity of P-gp-overexpressing the drug-resistant KBV20C cancer cell line. We have used the commercially-available epigenetic library, which includes 128 compounds. Using the cellular viability test, we also identified that NVP-BSK805 is highly sensitized to KBV20C-resistant cells and vincristine treatment. However, NVP-BSK805-induced sensitization was not observed in vincristine-treated sensitive KB parent cells, suggesting that the effects are specific to resistant cancer cells. Using FACS analysis, western blot, and Annexin V staining, we identified that NVP-BSK805 sensitized vincristine-treated KBV20C cells arrest via apoptosis and G2. Furthermore, sensitization potency of NVP-BSK805, in combination with vincristine, was measured in KBV20C cells when comparing them with P-gp inhibitor verapamil or another Jak2 inhibitor CEP-33779. We further investigated the mechanisms of NVP-BSK805 against sensitization of vincristine-treated KBV20C cells. The sensitization mechanism of NVP-BSK805 was mainly dependent on the inhibition of P-gp. In addition, ATPase activity was conducted to identify its potential role in NVP-BSK805 for P-gp inhibition. Both NVP-BSK805 and CEP-33779 showed high binding affinity docking scores -9.1 and -7.4, respectively, against the ABCB1 receptor protein. Collectively, inhibition of P-gp by NVP-BSK805 can increase vincristine-sensitivity in MDR cancer cells through increased apoptosis and G2 arrest. Our findings indicate that the Jak2 inhibitor may be a promising target in the treatment of patients resistant to antimitotic drugs.

Citation Format: Yu Jin Park, Ji Hyun Cheon, Ji Yeon Son, Sung Pil Yoon, Hyung Sik Kim. Co-treatment of NVP-BSK805 highly sensitizes drug-resistant cancer cells by increasing P-gp inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2058. doi:10.1158/1538-7445.AM2017-2058
Abstract 2074: Targeting SHP-1 mediated VEGF signaling to block the migration of human triple negative breast cancer
Authors: Su Jung-Chen , Mar Ai-Chung , Liu Chun-Yu , Chen Kuen-Feng , Shiau Chung-Wai
Published: July 2017

Patients with triple-negative breast cancer (TNBC) had an increased likelihood of distant recurrence and death, as compared with those with non-TNBC subtype. Regorafenib is a multi-receptor tyrosine kinase (RTK) inhibitor targeting oncogenesis and has been approved for metastatic colorectal cancer and advanced gastrointestinal stromal tumor. Recently, scientists have suggested that regorafenib also acts as a SHP-1 phosphatase agonist. In this study, we aimed to investigate the role of regorafenib in suppressing metastasis of TNBC cells through targeting the SHP-1/p-STAT3/VEGF-A axis. We first observed a significant correlation between migration ability and SHP-1/p-STAT3/VEGF-A expression in several human TNBC cell lines. Importantly, we also demonstrated that VEGF-A expression is correlated with worse disease-free and distant metastasis-free survival in clinical TNBC patients. Furthermore, we showed that regorafenib could inhibit the migration of human TNBC cells, which was related to downregulation of p-STAT3 and VEGF-A. To exclude the role of RTK inhibition in regorafenib-induced anti-metastasis, we synthesized a regorafenib derivative, SC-78, that had minimal effect on VEGFR2 and PDGFR kinase inhibition, while having more potent effects on SHP-1 activation. SC-78 demonstrated superior in vitro and in vivo anti-migration to regorafenib. This study indicated that the SHP-1/p-STAT3/VEGF-A axis is a potential therapeutic target for metastatic TNBC, and SC-78 may be a promising lead compound for suppressing metastasis of TNBC. (Grant supported by MOST 104-2628-B-075-001-MY3, MOST 105-2325-B-010-007, 105F026 )

Citation Format: Jung-Chen Su, Ai-Chung Mar, Chun-Yu Liu, Kuen-Feng Chen, Chung-Wai Shiau. Targeting SHP-1 mediated VEGF signaling to block the migration of human triple negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2074. doi:10.1158/1538-7445.AM2017-2074
Abstract 2076: Targeting the FGFR pathway in androgen receptor negative castration resistant prostate cancer
Authors: Morrissey Colm , Corey Eva , Brown Lisha , Coleman Ilsa , Nguyen Holly , Schweizer Michael , Nelson Peter
Published: July 2017

Metastatic castration-resistant prostate cancer (CRPC) has a poor prognosis and remains a significant therapeutic challenge. The continued importance of androgen receptor (AR) signaling as a growth and survival pathway in most advanced prostate cancer (PC) has prompted the development of therapeutics directed toward further suppressing AR ligands or the AR itself. However, total androgen blockade can give rise to AR-negative PC and currently there are no effective therapies for AR-negative PC. We have developed two novel patient-derived xenograft (PDX) models from a liver metastasis and a rib metastasis of a patient with CRPC: LuCaP 173.1 (Neuroendocrine; NE) and LuCaP 173.2 (Double negative: DN (AR-negative and NE-negative)). Using RNA-Seq we observed that both of these lines express high levels of fibroblast growth factors (FGF’s) and downstream effectors. We hypothesized that FGF signaling promotes survival and proliferation of NEPC and DNPC. To determine if blocking the FGFR survival pathway can attenuate the growth of NEPC/DNPC tumors, to characterize the molecular response and resistance to FGF signaling inhibition, and to support further evaluation in the clinic, we treated both PDX models with the FGFR inhibitor CH5183284. CH5183284 significantly reduced LuCaP 173.2 tumor volume (TV) (p<0.0001). The reduction in TV in CH5183284-treated animals bearing LuCaP 173.1 tumors was not as significant. To address this difference, we analyzed FGFR1 expression at the transcript and protein levels. Analysis of the FGFRs in the LuCaP 173.1 PDX model revealed a loss of FGFR1 expression. FGFR2 and FGFR3 transcripts were expressed at similar levels in both PDXs. The loss of FGFR1 expression may explain the low efficacy of CH5183284 in the LuCaP 173.1 PDX model. We are currently assessing the molecular pathways impacted by FGFR inhibition and mechanisms of resistance to treatment in these studies. We have demonstrated that FGFR inhibition attenuated tumor growth in FGFhigh AR-negative PC. We intend to target the FGFR survival pathway in additional NE and DNPC PDX models to investigate tumor heterogeneity in response to therapy and identify mechanisms of resistance. These studies will provide translational evidence that FGFR inhibitors could represent a new therapy for CRPC patients with AR-negative PC.

Citation Format: Colm Morrissey, Eva Corey, Lisha Brown, Ilsa Coleman, Holly Nguyen, Michael Schweizer, Peter Nelson. Targeting the FGFR pathway in androgen receptor negative castration resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2076. doi:10.1158/1538-7445.AM2017-2076
Abstract 2085: Development of a novel targeted therapy for malignant mesothelioma carcinoma by a midkine inhibitor
Authors: Fukazawa Takuya , Maeda Yuitaka , Yamatsuji Tomoki , Takaoka Munenori , Yoshida Masakazu , Ishida Naomasa , Iwai Miki , Yokota Etsuko , Yukawa Takuro , Haisa Minoru , Miyake Noriko , Ikeda Tomoko , Takigawa Nagio , Whitsett Jeffery , Naomoto Yoshio
Published: July 2017

Malignant pleural mesothelioma is an aggressive tumor of mesenchymal origin and is increasing worldwide as a result of widespread exposure to asbestos. The median survival of patients with mesothelioma from time of diagnosis ranges between 1 and 2 years. The mortality is expected to increase, at least until 2020, which is mainly due to the long latency (30-50 years) of the disease. Despite considerable advances in the understanding of its pathogenesis and etiology, malignant mesothelioma remains largely unresponsive to standard modalities of cancer therapy. Thus, there is an urgent need for new therapeutic options for mesothelioma.Midkine (MDK) is a heparin-binding growth factor that is highly expressed in many malignant tumors, including lung cancers. We have previously reported that a MDK inhibitor, iMDK, suppresses non-small cell lung cancer expressing MDK without harming normal cells. Importantly, iMDK inhibits the PI3 kinase / Akt pathway and induces apoptosis in MDK expressing non-small cell lung cancer cells. In the present study, we have investigated the antitumor effect of iMDK against malignant mesothelioma both in vitro and in vivo. 48 hours after treatment, iMDK dose-dependently inhibited cell growth of MDK expressing malignant mesothelioma cells. iMDK also suppressed colony formation of MSTO-211H mesothelioma cells. TUNEL positive cells were significantly increased in MSTO-211H cells 48 hours after iMDK treatment in a dose-dependent manner, confirming the induction of apoptosis in mesothelioma cells by iMDK. Combination treatment of iMDK and Bcl-2 inhibitor ABT-263 is more effective than each drug alone in MSTO-211H mesothelioma cells. Moreover, systemic administration of iMDK significantly inhibited tumor growth in a mesothelioma xenograft tumor in vivo. Inhibition of MDK with iMDK provides a potential therapeutic approach for the treatment of malignant mesothelioma that is driven by MDK.

Citation Format: Takuya Fukazawa, Yuitaka Maeda, Tomoki Yamatsuji, Munenori Takaoka, Masakazu Yoshida, Naomasa Ishida, Miki Iwai, Etsuko Yokota, Takuro Yukawa, Minoru Haisa, Noriko Miyake, Tomoko Ikeda, Nagio Takigawa, Jeffery Whitsett, Yoshio Naomoto. Development of a novel targeted therapy for malignant mesothelioma carcinoma by a midkine inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2085. doi:10.1158/1538-7445.AM2017-2085
Abstract 2086: Dominant role of receptor tyrosine kinase in the activation of MAPK signaling in BRAF non-V600 mutant cancers
Authors: Ebi Hiromichi , Kotani Hiroshi , Kitai Hidenori , Adachi Yuta , Yano Seiji
Published: July 2017

BRAF mutations are found in ~8% of all cancers. In addition to the commonest mutation in kinase domain at the V600, a wide range of other missense mutations (non-V600) have been reported. Non-V600 mutant BRAF protein was also shown to enhance MAPK signaling, suggesting the effectiveness of MEK inhibitors. However, the existence of feedback mechanism in MAPK singling and the roles of receptor tyrosine kinases (RTKs) in these cells are not fully understood. To interrogate this, BRAF non-V600 cell lines with intermediate/impaired kinase activity were treated with MEK inhibitor. RTKs involved in the upregulation of P-MEK following MEK inhibition in BRAF non-V600E mutant cell lines were determined by phosphor-RTK arrays. The effect of combinatorial inhibition of RTKs and MEK in BRAF non-V600 cancer was assessed in vitro and in vivo. By analyzing drug screen data, we first found cells with BRAF non-V600E mutation were less sensitive to MEK inhibition compared with BRAF V600E mutant cell lines and almost comparable to RAS/RAF wild-type cell lines. MEK inhibition did not induce P-MEK suppression and it resulted in significant upregulation of p-MEK compared to BRAF V600E mutant cell lines. Phospho-RTK arrays in the presence or absence of trametinib displayed basal phosphorylation of RTKs including EGFR, MET, and IGF1R, although the phosphorylation level was not consistently changed following MEK inhibition. Among these RTKs, treatment with the EGFR inhibitor erlotinib led to more complete suppression of P-ERK upon trametinib treatment. Furthermore, we found that erlotinib monotherapy downregulated P-ERK in BRAF non-V600 mutant cell lines in contrast that inhibition of RTKs had no effect on MAPK signaling in BRAF V600 mutant cells. While erlotinib treatment led to MAPK inhibition both in intermediate active and impaired kinase active BRAF mutant cells, p-MEK and p-ERK were more strongly suppressed in impaired type BRAF non-V600 mutant cells. The combination of EGFR inhibitor and MEK inhibitor suppressed cell growth and achieved tumor shrinkage in mice xenograft. These results suggest that RTKs, especially EGFR, are dominantly involved in the regulation of MAPK signaling in BRAF non-V600 cancer cells.

Note: This abstract was not presented at the meeting.

Citation Format: Hiromichi Ebi, Hiroshi Kotani, Hidenori Kitai, Yuta Adachi, Seiji Yano. Dominant role of receptor tyrosine kinase in the activation of MAPK signaling in BRAF non-V600 mutant cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2086. doi:10.1158/1538-7445.AM2017-2086
Abstract 2099: In vitro characterization of the effect of nazartinib against non-small cell lung cancer activating clinically relevant EGFR mutants
Authors: Masuzawa Keita , Yasuda Hiroyuki , Hirano Toshiyuki , Nukaga Shigenari , Hasegawa Hanako , Hamamoto Junko , Naoki Katsuhiko , Soejima Kenzo , Betsuyaku Tomoko
Published: July 2017

Purpose: Multiple EGFR-TKIs are available and under development to treat patients with lung cancer harboring EGFR mutations. Nazartinib is one of the 3rd generation EGFR-TKIs targeting EGFR T790M as well as common mutations such as L858R and exon 19 deletions. Today, there is no clear guideline regarding which EGFR-TKIs should be used for which mutations. The purpose of this study is to clarify which EGFR-TKIs including nazartinib are best for each EGFR mutation, especially exon 20 insertion mutations using in vitro modeling.

Experimental design: We evaluated drug sensitivity and downstream signaling of human lung cancer cell lines (PC9, H3255, H1975, PC9ER, BID007) and Ba/F3 cells harboring multiple types of EGFR mutations for 1st- (erlotinib), 2nd- (afatinib) and 3rd- (osimertinib and nazartinib) generation EGFR-TKIs by MTS assay and western blotting. An in vitro model of mutation specificity was created by calculating the ratio of IC50 values between mutated and wild type EGFRs.

Results: The model of mutation specificity identified a wide therapeutic window of each EGFR-TKIs for exon 19 deletions and L858R. On the other hand, osimertinib and nazartinib have wide therapeutic window for T790M positive mutations in human cell lines and Ba/F3 cells. In human cell lines and Ba/F3 cells harboring exon 19 deletions or L858R, afatinib dramatically inhibited the phosphorylation of EGFR, AKT, and ERK. Afatinib and 3rd generation EGFR-TKIs, osimertinib and nazartinib, effectively inhibited the phosphorylation of EGFR, AKT, and ERK in T790M positive cells. For EGFR exon 20 insertion mutations, althogh afatinib, osimertinib and nazartinib effectively inhibited the phosphorylation of EGFR, AKT, and ERK in several exon 20 insertion mutations, osimertinib and nazartinib were potent and presented a wide therapeutic window.

Conclusion: Nazartinib as well as osimertinib has wide therapeutic windows for exon 19 deletions, L858R, T790M and some exon 20 insertions .

Citation Format: Keita Masuzawa, Hiroyuki Yasuda, Toshiyuki Hirano, Shigenari Nukaga, Hanako Hasegawa, Junko Hamamoto, Katsuhiko Naoki, Kenzo Soejima, Tomoko Betsuyaku. In vitro characterization of the effect of nazartinib against non-small cell lung cancer activating clinically relevant EGFR mutants [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2099. doi:10.1158/1538-7445.AM2017-2099
Abstract 2102: ONC201 targets AR and AR-V7 signaling pathways, reduces PSA and synergizes with everolimus in castration resistant prostate cancer
Authors: Lev Avital , Lulla Amriti R. , Dicker David T. , El-Deiry Wafik S.
Published: July 2017

Androgen receptor (AR) signaling plays a key role in prostate cancer progression; thus Androgen Deprivation Therapy (ADT) is a mainstay therapy for patients with advanced prostate cancer. However, in most cases the tumor becomes androgen-independent and resistant to ADT with patients ultimately progressing to metastatic castration resistant prostate cancer (mCRPC). Constitutively activated AR splice variants (AR-Vs) have emerged as major mediators of resistance to AR-targeted therapy and progression of mCRPC, representing an important therapeutic target for mCRPC. Out of at least 15 AR-Vs described thus far, AR-V7 is the most abundant in prostate cancer and its expression correlates with ADT resistance. ONC201 is the founding member of the imipridone class of small molecules that induces apoptosis in a variety of tumor types tested. It is currently in Phase I/II clinical trials for advanced solid tumors and hematological malignancies, including mCRPC with encouraging activity observed in patients in early clinical testing (Stein et al., ASCO, 2016). We demonstrate here that ONC201 treatment induces apoptosis in both castration-resistant and –sensitive human prostate cancer cell lines. Furthermore, an in-vitro synergistic effect is observed with ONC201 and FDA approved drugs for prostate cancer such as enzalutamide, docetaxel and everolimus. Mechanistically, we found that ONC201 inhibits both AR and AR-V7 signaling pathways. Analysis of AR+ cell lines stimulated with DHT showed a significant decrease in both RNA and protein levels of AR, AR-V7, PSA and other AR-target genes following ONC201 treatment. Ongoing experiments are aimed at better understanding the molecular and cellular mechanisms that enable ONC201 to inhibit the AR signaling pathway. In-vivo studies with AR-negative hormone refractory prostate cancer xenografts demonstrate single agent ONC201 anti-tumor efficacy. Ongoing studies are further evaluating the in-vivo efficacy of ONC201 as a single agent or in combination with enzalutamide and everolimus using mouse models of both castration-resistant and -sensitive prostate cancer. These preclinical results indicate that ONC201 is well suited to address mCRPC, including tumors that harbor AR-V7, as a single agent that may be combined synergistically with enzalutamide or everolimus . With these observations we envision further development a combination of ONC201 plus everolimus in CRPC with or without enzalutamide resistance.

Citation Format: Avital Lev, Amriti R. Lulla, David T. Dicker, Wafik S. El-Deiry. ONC201 targets AR and AR-V7 signaling pathways, reduces PSA and synergizes with everolimus in castration resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2102. doi:10.1158/1538-7445.AM2017-2102
Abstract 2103: NVP-FGF401: Cellular and in vivo profile of a novel highly potent and selective FGFR4 inhibitor for the treatment of FGF19/FGFR4/KLB+ tumors
Authors: Weiss Andreas , Porta Diana Graus , Reimann Flavia , Buhles Alexandra , Stamm Christelle , Fairhurst Robin A. , Kinyamu-Akunda Jacqueline , Sterker Dario , Murakami Masato , Wartmann Markus , Wang Youzhen , Engelman Jeffrey A. , Hofmann Francesco , Sellers Wiliam R.
Published: July 2017

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and a deadly disease. Treatment options are limited and prognosis generally is poor. Aberrant signaling through the fibroblast growth factor 19 (FGF19) - fibroblast growth factor receptor 4 (FGFR4) axis has been implicated in the development of HCC, and recently FGF19 has been determined as a specific driver gene amplification in a subset of liver tumors and cancer cell lines. Here, we describe the cellular and in vivo profile of NVP-FGF401, a highly potent and selective, first in class, reversible-covalent small-molecule inhibitor of the kinase activity of FGFR4. NVP-FGF401 is exquisitely selective for FGFR4 versus other FGFR family members and all other kinases. We show that among the FGF19-amplified liver cancer cells in the cancer cell line encyclopedia (CCLE), only those with concomitant expression of β-klotho (KLB), a co-receptor for FGF19 that facilitates its binding to FGFR4, are sensitive to NVP-FGF401. NVP-FGF401 has good oral PK properties and shows an excellent in vivo PK/PD relationship. NVP-FGF401 has remarkable anti-tumor activity in mice bearing HCC tumor xenografts and PDX models that are positive for FGF19, FGFR4 and KLB. NVP-FGF401 is the first FGFR4 inhibitor to enter clinical trials, and a PhI/II study is currently ongoing in HCC and other types of solid tumors.

Citation Format: Andreas Weiss, Diana Graus Porta, Flavia Reimann, Alexandra Buhles, Christelle Stamm, Robin A. Fairhurst, Jacqueline Kinyamu-Akunda, Dario Sterker, Masato Murakami, Markus Wartmann, Youzhen Wang, Jeffrey A. Engelman, Francesco Hofmann, Wiliam R. Sellers. NVP-FGF401: Cellular and in vivo profile of a novel highly potent and selective FGFR4 inhibitor for the treatment of FGF19/FGFR4/KLB+ tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2103. doi:10.1158/1538-7445.AM2017-2103