bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4225: A novel pharmacological inhibitor CEP1430 for human pancreatic cancer stem cells
Authors: Jani Jitesh , Amiri Mandana , Sharma Cristian , Harris Joshua , Satish Shruthi , Sharma Michael , Rodriguez Robert , Navel Miriam , Amezcua Natalee , Sharma Shaleekha , Sharma Arun , Desai Dhimant , Amin Shantu , Narayan Satya , Punzalan Rubio , Sharma Jay P.
Published: August 2015

Pancreatic cancer is one of the most devastating human malignancies with an estimate yearly death of 280,000 and an overall median 5-year survival rate of less than 5%. The development of relevant preclinical models of the disease to evaluate novel therapeutic strategies can accelerate basic research findings into the much needed clinical application. We used our recently established three-dimensional (3D) in vitro culture assay system that resembles in-vivo tumor growth to screen small molecule libraries. We identified CEP1430, a sonic hedgehog (hh) pathway inhibitor as a potential drug lead molecule. We selected this molecule for further evaluation because the hh pathway is important for the maintenance of cancer stem cells. The CEP1430 treatment markedly inhibited in-vitro growth of human pancreatic CSC (IC50 value of ∼10 nM). In-vitro, CEP1430 induced apoptotic cell death of CSC and reduced pro-angiogenic but increased anti-angiogenic marker expression at the doses tested. In-vivo efficacy of CEP 1430 was evaluated in female SCID mice bearing human pancreatic CSC. The once daily administration (ip) of CEP1430 (doses:10, 15, and 20 mg/kg) for 30 days resulted in 80%, 89% and 90% tumor growth inhibition. The tumor growth inhibitory effect of CEP1430 in all treatment groups was statistically significant in comparison to vehicle treated control (P<0.001). The administration of CEP1430 for a period of 30 days was well tolerated without significant changes in body weight or toxicity by histological examination of tissues and organs. We are using proteomic and miRNA platforms to monitor biomarkers of response, mode of action and selectivity of CEP1430. Further pre-clinical in-vivo studies are ongoing to project human dose and schedule as monotherapy and in combination with therapeutic vaccination to advance CEP1430 for clinical investigation.

Citation Format: Jitesh Jani, Mandana Amiri, Cristian Sharma, Joshua Harris, Shruthi Satish, Michael Sharma, Robert Rodriguez, Miriam Navel, Natalee Amezcua, Shaleekha Sharma, Arun Sharma, Dhimant Desai, Shantu Amin, Satya Narayan, Rubio Punzalan, Jay P. Sharma. A novel pharmacological inhibitor CEP1430 for human pancreatic cancer stem cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4225. doi:10.1158/1538-7445.AM2015-4225
Abstract 4231: Combination of epigenetic, differentiation and DNA damaging agents induce tumor cell death and stem cell depletion in breast cancer
Authors: Merino Vanessa F. , Nguyen Nguyen , Sadik Helen , Cho Soonweng , Cope Leslie , Zhou Xian C. , Zhang Zhe , Chen Qian , Pan Duojia , Huso David L. , Ali Syed , Adams Christina , Győrffy Balázs , Sukumar Saraswati
Published: August 2015

The histone deacetylase inhibitor, entinostat, is a new-generation epigenetic drug, which has recently demonstrated notable clinical efficacy when used in combination with standard therapy. Retinoids induce differentiation in various types of stem cells. However, its delivery to patients is challenging because of its rapid metabolism. Also, epigenetic changes in the retinoic acid receptors often render cancer cells retinoid-resistant. We have shown that a combination of entinostat, all-trans retinoic acid (ATRA) and doxorubicin causes significant regression of xenografts of triple negative breast cancer (TNBC) cells and investigated the mechanism underlying the effectiveness of this combination therapy. Combinations of entinostat, retinoic acid and doxorubicin were optimal in causing tumor regression in triple negative breast cancer xenografts. Gene expression analysis of treated TNBC cells identified genes most effectively reprogrammed by entinostat and doxorubicin (ED) combination therapy. These genes are involved in cell cycle arrest, inflammation and differentiation, which are related to better survival outcome in patients. Entinostat sensitizes the cells to doxorubicin-induced growth arrest, resulting in increased apoptosis and necrosis. Adding ATRA to ED regulated interferon genes and members of the cancer/testis antigens (CTA) and tripartite motif (TRIM) family of proteins and induces inflammation in nude mice. Entinostat/ATRA/dox therapy was most effective to target breast cancer stem cells (BCSC) in limiting dilution assays of growth in mammary fat pads. The epithelium-specific ETS transcription factor-1 (ESE-1 or ELF3), known to regulate cellular proliferation and differentiation mediates the epigenetic differentiation effect. Patient-derived distant metastases responded to entinostat/ATRA/dox therapy in culture. Thus, the combination therapy may have significant effects in decreasing both local and metastatic growth in breast cancer, especially in decreasing recurrence by targeting breast cancer stem cells.

Citation Format: Vanessa F. Merino, Nguyen Nguyen, Helen Sadik, Soonweng Cho, Leslie Cope, Xian C. Zhou, Zhe Zhang, Qian Chen, Duojia Pan, David L. Huso, Syed Ali, Christina Adams, Balázs Győrffy, Saraswati Sukumar. Combination of epigenetic, differentiation and DNA damaging agents induce tumor cell death and stem cell depletion in breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4231. doi:10.1158/1538-7445.AM2015-4231
Abstract 4233: Wnt pathway antagonist ipafricept (FZD8-Fc, OMP-54F28) inhibits tumor growth and reduces tumor-initiating cell frequency in ovarian patient-derived xenograft models
Authors: Fischer Marcus M. , Yen Wan-Ching , Zheng Chun , Henner Randall , Cattaruzza Fiore , Tang Tracy , Yeung Pete , Biswas Tanuka , Lewicki John , Gurney Austin , Kapoun Ann M. , Hoey Timothy
Published: August 2015

Ovarian cancer is the deadliest gynecologic malignancy and the fifth leading cause of death from cancer in women in the U.S. The Wnt/beta-catenin pathway, which signals through the Frizzled (FZD) receptor family and several co-receptors, has long been implicated in cancer. We have developed ipafricept (FZD8-Fc, OMP-54F28), a recombinant fusion protein consisting of the ligand-binding domain of FZD8 and a human IgG1 Fc fragment. This fusion protein blocks Wnt signaling induced by multiple Wnt family members by binding and sequestering WNT.

Using minimally passaged ovarian patient-derived xenograft tumors (PDX), we demonstrate that ipafricept is efficacious in combination with chemotherapy in four of eight ovarian cancer PDX tumors examined. Utilizing an in vivo serial transplantation assay, we quantified a reduction of the tumor initiating cell frequency by ipafricept in combination with paclitaxel. Additionally, we have discovered that pre-treatment with ipafricept several days prior to paclitaxel therapy enhances the activity of both agents when compared to delivering the drugs simultaneously.

The anti-tumor effect observed is directly associated with a modulation of Wnt pathway gene sets. In responsive tumors, we discovered that a large number of WNT target genes were significantly down-regulated by ipafricept (e.g, AXIN2, LRP5/6, and FZD8). Conversely, in non-responsive tumors, these genes were either unchanged or up-regulated by the combination therapy. Histologic analysis revealed that total beta-catenin protein levels were reduced by ipafricept alone and in combination with paclitaxel in responsive tumors but were unchanged in non-responsive tumors. We are using these tumors to develop biomarkers that can be used clinically.

Our data demonstrates the potential therapeutic benefit of targeting Wnt signaling in ovarian cancer. A Phase 1b clinical trial is currently examining ipafricept in combination with paclitaxel and carboplatin in patients with recurrent platinum-sensitive ovarian cancer.

Citation Format: Marcus M. Fischer, Wan-Ching Yen, Chun Zheng, Randall Henner, Fiore Cattaruzza, Tracy Tang, Pete Yeung, Tanuka Biswas, John Lewicki, Austin Gurney, Ann M. Kapoun, Timothy Hoey. Wnt pathway antagonist ipafricept (FZD8-Fc, OMP-54F28) inhibits tumor growth and reduces tumor-initiating cell frequency in ovarian patient-derived xenograft models. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4233. doi:10.1158/1538-7445.AM2015-4233
Abstract 4272: Potent in situ cancer immunotherapy with synthetic human STING-activating cyclic dinucleotides
Authors: Glickman Laura Hix , Kanne David B. , Gauthier Kelsey E. , Katibah George E. , Leong Justin J. , Metchette Ken , Dubensky Thomas W. , McWhirter Sarah M.
Published: August 2015

Spontaneous tumor-initiated T cell priming is dependent on IFN-β production by tumor-resident dendritic cells. Based on recent observations indicating that IFN-β expression was dependent upon activation of the host STING (Stimulator of Interferon Genes) pathway, we hypothesized that direct engagement of STING through intratumoral administration of specific agonists would result in effective anti-tumor therapy. To this end, we generated novel synthetic cyclic dinucleotide (CDN) derivatives with superior STING-activating and anti-tumor properties. The most potent molecule contains a 2′-5′ and 3′-5′ phosphate bridge that increases its affinity for STING at least 10-fold. Additionally, sulfur atoms at the non-bridging oxygens of the internucleotide phosphate bridge enable both superior STING binding affinity, as well as resistance to host cell phosphodiesterases. Importantly, the lead molecule activates PBMCs from a panel of human donors representing all known STING alleles, including homozygotes for the most refractory allele. Intratumoral injection of the lead CDN molecule induced profound regression of established B16 melanoma tumors, generated substantial systemic immune responses capable of rejecting distant metastases and provided long-lived immunologic memory. Cures in entire cohorts of mice bearing well-established 4T1 mammary and CT26 colon carcinoma models correlated with induction of cytokine-mediated innate and adaptive antigen-specific T cell immunity, both systemically and in the tumor microenvironment. Immune activation and anti-tumor efficacy was lost in mice encoding non-functional STING. In vivo activation of STING with the lead CDN administered by multiple routes demonstrated a high safety and tolerability margin in preclinical toxicology studies. In addition, pharmacokinetic analysis indicates that the lead CDN compound was rapidly cleared from systemic circulation, consistent with pulsatile STING activation and transient systemic cytokine and hematological changes. These results demonstrate that CDNs have high translation potential for treatment strategies to induce activation of the tumor microenvironment, leading to effective tumor-initiated T cell priming and anti-tumor immunity.

Citation Format: Laura Hix Glickman, David B. Kanne, Kelsey E. Gauthier, George E. Katibah, Justin J. Leong, Ken Metchette, Thomas W. Dubensky, Sarah M. McWhirter. Potent in situ cancer immunotherapy with synthetic human STING-activating cyclic dinucleotides. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4272. doi:10.1158/1538-7445.AM2015-4272
Abstract 4274: Anticancer mechanisms of a small amphipathic molecule, LTX-401, against B16 melanoma cancer cells
Authors: Eike Liv-Marie , Mauseth Brynjar , Camilio Ketil , Rekdal Oystein , Sveinbjornsson Baldur
Published: August 2015

In the present study we investigated the mechanism behind the killing of B16F1 murine melanoma cells by the small amphipathic β(2,2)-amino acid derivative, LTX-401 (Mw<500Da). In vitro, LTX-401 induced lytic cell death and the release of Danger-Associated-Molecular-Pattern Molecules(DAMPs) such as ATP and HMGB-1. In addition, the cells released pro-Cathepsin-B and cytochrome-c following LTX-401 treatment. Flow cytometry and confocal microscopy studies revealed reduced signal from the lysomal dye Lysotracker-DND-26, indicating loss of lysomal integrity. Furthermore, flow cytometry analysis showed that the mitochondrial membrane potential was unaffected in the LTX-401 treated cells. Transmission electron microscopy of LTX-401 treated cells showed little or no ultra structural changes in the mitochondria. The in vivo antitumor effect of LTX-401 against intradermally established B16F1 melanoma was assessed in syngeneic mice. Intratumoral administration of the molecule caused rapid tumor necrosis and complete tumor regression in the majority of the animals treated. In conclusion, these findings demonstrate that LTX-401 has the ability to cause immunogenic cell death in cancer cells and induce complete tumor regression in solid tumors and thus might have a potential as an immunotherapeutic agent.

Citation Format: Liv-Marie Eike, Brynjar Mauseth, Ketil Camilio, Oystein Rekdal, Baldur Sveinbjornsson. Anticancer mechanisms of a small amphipathic molecule, LTX-401, against B16 melanoma cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4274. doi:10.1158/1538-7445.AM2015-4274
Abstract 4277: Oral administration of a traditional herbal remedy, JC001, suppresses pancreatic tumorigenesis in mice via regulating immune cell functions
Authors: Jan Ming-Shiou , Hsu Fong-Rong , Lin You-Chain , Chuang Shu-Han , Lin Jia-Wei , Chuang Meng-Hsein , Hsu Li-Jin
Published: August 2015

The traditional Chinese herbal medicine JC001 is widely used as an effective liver-protecting remedy in Taiwan and China for decades. We have first examined the antitumor effects of JC001 using both mouse xenograft and oncogene-induced tumor models. Our results indicated that the numbers of M1-type macrophages, mitogen-stimulated T cell proliferation and natural killer cell activity were increased in wild-type mice with oral administration of JC001. Interestingly, continuous administration of JC001 for a month markedly reduced the numbers and the sizes of tumor nodules in a mouse pancreatic xenograft model. In contrast to this observation in immune-competent mice, our data revealed that the average tumor size in JC001-administrated nude mice was comparable with that of the control tumor-bearing nude mice without JC001 treatment, suggesting that JC001-induced antitumor activity is mediated by T cells. Adoptive transfer of the splenocytes isolated from immune-competent mice with JC001 treatment into tumor-bearing nude mice reduced tumor growth in these T cell-deficient mice. Moreover, increased cytotoxic activity of natural killer (NK) cells was also observed in mice treated with JC001. In an oncogene-induced tumor model, orally administered JC001 significantly suppressed caerulein-triggered development of pancreatic neoplasias and cancer cell metastasis in KrasG12D/w Pdx-Cre transgenic mice. Together, our results clearly suggest that JC001 exerts immunomodulatory activity mainly through regulating T and NK cell responses to suppress pancreatic cancer development and metastasis.

Citation Format: Ming-Shiou Jan, Fong-Rong Hsu, You-Chain Lin, Shu-Han Chuang, Jia-Wei Lin, Meng-Hsein Chuang, Li-Jin Hsu. Oral administration of a traditional herbal remedy, JC001, suppresses pancreatic tumorigenesis in mice via regulating immune cell functions. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4277. doi:10.1158/1538-7445.AM2015-4277
Abstract 4289: Targeting of phosphatidylserine by monoclonal antibodies enhances the activity of immune checkpoint inhibitors in breast tumors
Authors: Gong Jian , Yin Shen , Nguyen Van , Hutchins Jeff , Freimark Bruce D.
Published: August 2015

Phosphatidylserine (PS) is a phospholipid normally residing in the inner leaflet of the plasma membrane that becomes exposed on tumor vascular endothelial cells (ECs) and tumor cells. PS exposure becomes enhanced in response to chemotherapy, irradiation, and oxidative stresses in the tumor microenvironment. PS exposure in tumors promotes an immunosuppressive microenvironment which includes the recruitment of myeloid derived suppressor cells (MDSCs), immature dendritic cells and M2-like macrophages, as well as, the production of anti-inflammatory cytokines. Binding of PS targeting antibodies on tumor endothelial cells, tumor cells and their secreted microparticles triggers an Fc-FcR mediated pro-inflammatory cellular and cytokine response that reverses the immunosuppressive PS meditated checkpoint, thereby enhancing anti-tumor immunity. A chimeric PS-targeting antibody, bavituximab, is being used in combination with chemotherapy to treat patients with solid tumors in multiple late-stage clinical trials. Using breast tumors in immune competent mice, we demonstrate PS targeting antibodies enhance the anti-tumor activity of combination therapies including anti-PD-1 antibodies. Tumor growth inhibition correlates with statistically significant increases in the infiltration of CD8+ T cells and a reduction of myeloid-derived suppressor cells (MDSCs). The combination of these mechanisms promotes strong, localized, anti-tumor responses without the side-effects of systemic immune activation.

Citation Format: Jian Gong, Shen Yin, Van Nguyen, Jeff Hutchins, Bruce D. Freimark. Targeting of phosphatidylserine by monoclonal antibodies enhances the activity of immune checkpoint inhibitors in breast tumors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4289. doi:10.1158/1538-7445.AM2015-4289
Abstract 4303: Programmed death ligand 1 (PD-L1) expression in paired melanoma tumor samples
Authors: Steiniche Torben , Vestergaard Danielsen Allan , Wang Zhen (Adelle) , Switten Nielsen Patricia , Bastholt Lars , Schmidt Henrik , Svane Inge Marie , Dolled-Filhart Marisa , Emancipator Kenneth , Wu Dianna Y. , Busch-Sorensen Michael , Zhou Wei
Published: August 2015

Background: There is limited information on changes in PD-L1 expression levels over time in melanoma.

Methods: PD-L1 expression was measured in melanoma tumor samples collected at different time points from the same patient using a prototype immunohistochemistry (IHC) assay with the 22C3 antibody. PD-L1 positivity was defined as staining in ≥1% of cells. The concordance of PD-L1 expression in paired samples was analyzed by treating the IHC proportion score as a continuous variable or classifying staining as positive or negative.

Results: 48 patients were included. Median age was 65 years (range, 23-85), 73% were male, and 60% had stage I-IIIA disease. All first samples and 85% of second samples were surgical samples. The median interval between sample collection dates was 25.3 months (range, 3.1-203.5). There was no statistically significant correlation of the PD-L1 IHC proportional score between paired samples (Pearson correlation coefficient, 0.13). 40% of patients had an increased proportion score at the second time point, and 10% had a decreased score. The prevalence of PD-L1 positivity was 31% in first samples and 46% in second samples. The concordance rate was 65% (95% CI, 49%-78%) when PD-L1 expression was categorized as positive or negative (Table). The concordance rate was similar in paired samples collected within and beyond 2 years.

Concordance of PD-L1 Expression in Paired Melanoma Samples (N = 48)Later Time PointPD-L1 ExpressionPositive, n (%)Negative, n (%)Earlier Time PointPositive10 (20.8)5 (10.4)Negative12 (25.0)21 (43.7)

Conclusion: Our preliminary analysis did not suggest a significant correlation of PD-L1 expression in paired melanoma samples collected at different time points. Similar results were observed when samples were categorized as PD-L1 positive or PD-L1 negative. The 35% discordance rate between initial and subsequent tumor samples should be considered if PD-L1 expression is used for selection of enrollment in clinical trials.

Citation Format: Torben Steiniche, Allan Vestergaard Danielsen, Zhen (Adelle) Wang, Patricia Switten Nielsen, Lars Bastholt, Henrik Schmidt, Inge Marie Svane, Marisa Dolled-Filhart, Kenneth Emancipator, Dianna Y. Wu, Michael Busch-Sorensen, Wei Zhou. Programmed death ligand 1 (PD-L1) expression in paired melanoma tumor samples. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4303. doi:10.1158/1538-7445.AM2015-4303
Abstract 4323: ALK overexpression is associated with activation of PI3K/AKT signaling pathway in PTC
Authors: Bu Rong , Prabhakaran Sarita , Beg Shaham , Jehan Zeenath , Siraj Abdul K. , Ahmed Maqbool , Hussain Azhar , Alsobhi Saif A. , Al-Dayel Fouad , Uddin Shahab , Al-Kuraya Khawla S.
Published: August 2015

Aberrant activation of anaplastic lymphoma kinase (ALK) gene caused by mutation, rearrangement or overexpression plays a fundamental role in tumorigenesis in several tumors and represents an important therapeutic target. Currently, only limited data is available on thyroid cancer with respect to the genetic alteration of ALK. Therefore we investigate the ALK overexpression and amplification, and its correlation with various clinicopathological features and molecular biomarkers in a large cohort of 1040 Middle Eastern PTC. In our study, ALK protein expression was determined by immunohistochemistry. ALK gene amplification and rearrangement were analyzed by in situ hybridization (FISH). We also correlated the data with clinicopathological characteristics and other molecular markers. Our data showed that ALK is overexpressed in 136 of the 997 (13.6%) PTC samples. ALK amplification and rearrangement were not observed by FISH. ALK overexpression was significantly associated with surgical margin, but had no effect on the survival of PTC patients. Interestingly, ALK overexpression was found to be significantly correlated with the higher expression of pAKT and PIK3CA in PTC samples, suggesting that ALK overexpression is associated with activation of PI3K/AKT signaling pathway in PTC. In addition, ALK overexpression is also correlated with overexpression of anti-apopototic marker XIAP and BCL-XL and cell cycle regulatory marker SKP2. Altogether, our results suggest that ALK overexpression presents in a small subset of samples and is not associated with survival in PTC. However ALK overexpression is significantly correlated with PI3K/AKT signaling pathway and might provide a potential therapeutic target for PTC patients with ALK overexpression.

Citation Format: Rong Bu, Sarita Prabhakaran, Shaham Beg, Zeenath Jehan, Abdul K. Siraj, Maqbool Ahmed, Azhar Hussain, Saif A. Alsobhi, Fouad Al-Dayel, Shahab Uddin, Khawla S. Al-Kuraya. ALK overexpression is associated with activation of PI3K/AKT signaling pathway in PTC. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4323. doi:10.1158/1538-7445.AM2015-4323
Abstract 4325: The role of FGFR fusion genes as novel oncogenic targets
Authors: Martinez Cardona Gabriela , Bell Katherine , Gaffney Dana , Portale Joseph , Platero Suso , Lorenzi Matthew , Karkera Jayaprakash
Published: August 2015

Fusion genes are chromosomal aberrations that are found in many cancers and can be used as prognostic markers and drug targets in clinical practice. Gene fusions can lead to the production of oncogenic fusion proteins or to enhanced expression of oncogenes. Advances in next-generation sequencing technologies have made possible to identify more efficiently novel fusion proteins in cancer. Recently, several FGFR fusion genes with intact kinase domains have been identified in bladder, lung, breast, thyroid, oral, and prostate cancers, as well as other tumor types. To date, several FGFR3 partner genes have been identified. In this study, we focused on the FGFR3-BAIAP2L1 and FGFR3-TACC3 gene fusions and investigated their tumorigenic activity, mechanism of activation, and sensitivity to the FGFR inhibitor JNJ-42756493. To determine the role and significance of FGFR fusion genes in cancer, FGFR fusion expression constructs were designed and individually transfected into normal rat kidney epithelial cells. FGFR fusion overexpressing cells not only showed increased cell proliferation, but also exhibited anchorage-independent cell growth. Cells harboring the FGFR fusions showed increased sensitivity to the FGFR inhibitor JNJ-42756493 in vitro, whereas the wild-type FGFR3 did not in the absence of FGF ligands. In addition, Western blotting analyses indicated that the overexpression of the FGFR fusions resulted in highly activated proteins that induce signaling via the MAPK pathway. These findings underline the oncogenic potential of the FGFR fusion genes and highlight their unique potential as predictive biomarkers in the selection of patients for FGFR-targeted therapy.

Citation Format: Gabriela Martinez Cardona, Katherine Bell, Dana Gaffney, Joseph Portale, Suso Platero, Matthew Lorenzi, Jayaprakash Karkera. The role of FGFR fusion genes as novel oncogenic targets. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4325. doi:10.1158/1538-7445.AM2015-4325
Abstract 4359: Characterization of GalNAc-conjugated generation 2.5 ASOs in DEN and DEN/CCL4-induced HCC tumors
Authors: Schmidt Joanna , Jo Minji , Zhou Tianyuan , Kim Youngsoo , MacLeod A. R.
Published: August 2015

The worldwide rate of hepatocellular carcinoma (HCC) occurrence is rising rapidly; however, outside of transplantation, few effective treatment options are available. Hepatocellular carcinogenesis is a complex, multistep process involving many genetic alterations, often occurring in targets that are considered “undruggable” by conventional therapeutic modalities. Antisense oligonucleotide (ASO) technology offers the potential to target these undruggable pathways in HCC tumors in vivo and to determine the sensitivity of HCC to the ablation of these pathways. Using either the diethylnitrosamine (DEN) induced mouse HCC model or DEN in combination with the profibrotic agent carbon tetrachloride (CCl4), we first examined gene expression changes in induced HCC tumors. DEN-induced HCC has a very long latency period (∼8 months). We demonstrate that mice injected with DEN and CCl4 developed HCC with a shorter latency and a higher tumor incidence. We also identified several genes of interest that could potentially be HCC drivers and targets for ASO therapy. Conjugation of ASOs with N-acetyl D-galactosamine (GalNAc) has been shown to increase ASO activity >10x in normal liver. Here we demonstrate that GalNAc conjugated ASOs show similar increased potency in HCC tumors and the complete depletion of Myd88 protein levels. Importantly, in addition to the ability to potently inhibit Myd88 levels in tumors, GalNAc-conjugated Myd88 ASOs also resulted in significantly reduced tumor burden. These data demonstrate that GalNAc-conjugated Gen 2.5 ASOs have potent activity in HCC tumors and that Myd88 maybe be an attractive therapeutic target in this disease.

Citation Format: Joanna Schmidt, Minji Jo, Tianyuan Zhou, Youngsoo Kim, A. R. MacLeod. Characterization of GalNAc-conjugated generation 2.5 ASOs in DEN and DEN/CCL4-induced HCC tumors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4359. doi:10.1158/1538-7445.AM2015-4359
Abstract 4372: Phosphodiesterase 10A inhibition suppresses lung tumor cell growth by activating PKG to inhibit ras and Wnt signaling
Authors: Zhu Bing , Lee Kevin , Canzoneri Joshua , Ramirez-Alcantara Veronica , Sigler Sara , Gary Bernard , Butler Ethan , Keeton Adam , Chen Xi , Boyd Michael , Piazza Gary
Published: August 2015

We recently reported that phosphodiesterase 10A (PDE10) is overexpressed in colon tumors and essential for colon tumor cell growth (Li et al., Oncogene 2014), but a role in lung cancer has not been well studied. Human non-small cell lung cancer (NSCLC) cell lines were found to express appreciably higher PDE10 levels compared with normal airway epithelial cells, while silencing of PDE10 expression with siRNA or inhibition of PDE10 activity with small molecule inhibitors selectively inhibits NSCLC cell growth. Here we study the mechanism by which PDE10 inhibitors suppress NSCLC cell growth. At concentrations effective for inhibiting NSCLC cell growth, the PDE10 inhibitor, PQ10 rapidly increases intracellular cGMP levels as determined by a luminescence biosensor assay. Within the same concentration range and time period, PQ10 activates PKA and PKG, demonstrated by an increase in phosphorylation of the substrate, VASP at Ser157 and Ser239, respectively. Under the same conditions, PQ10 suppresses the phosphorylation of Erk1/2 (Thr202/Tyr204), MEK1/2 (Ser217/Ser221) and down-stream p90RSK (Ser380). Similarly, PQ10 increases the phosphorylation of β-catenin at Ser552, but showed no effect on phospho-Ser675 levels. After longer durations of treatment, PQ10 reduces β-catenin levels, as well as proteins that are regulated by β-catenin-dependent TCF/LEF-transcriptional activity, such as survivin and cyclin D1. These effects were mimicked by a novel structurally unrelated PDE10 inhibitor, ADT-020 that selectively inhibits the growth of NSCLC cells and increases cGMP levels in a manner similar to PQ10. ADT-020 also activates PKG in NSCLC cells demonstrated by higher phospho-Ser239 VASP levels and lower β-catenin and survivin levels. These observations suggest that PDE10 inhibition and activation of PKG can simultaneously suppress ras and Wnt signaling that are essential for lung tumor cell growth. Supported by NIH grants 1R01CA155638 and 1R01CA131378 (Piazza).

Citation Format: Bing Zhu, Kevin Lee, Joshua Canzoneri, Veronica Ramirez-Alcantara, Sara Sigler, Bernard Gary, Ethan Butler, Adam Keeton, Xi Chen, Michael Boyd, Gary Piazza. Phosphodiesterase 10A inhibition suppresses lung tumor cell growth by activating PKG to inhibit ras and Wnt signaling. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4372. doi:10.1158/1538-7445.AM2015-4372
Abstract 4395: Strategy to overcome inherent TRAIL-based therapeutic limitations
Authors: Oh Yumin , Swierczewska Maggie , Lee Seulki
Published: August 2015

TNF-related apoptosis-inducing ligand (TRAIL) is a promising anti-cancer agent because of its selective ability to induce apoptosis in activated immune cells or cancer cells with minimal toxicity in normal cells. However, a short biological half-life and the development of inherent TRAIL resistance in a variety of cancer cells, including colorectal cancer cells (CRC), results in the poor performance of TRAIL as a chemotherapeutic agent. To overcome these limitation, we developed PEGylated TRAIL (PEG-TRAIL) to compensate the short half-life of TRAIL offering improved pharmacokinetics in non-human primates. In parallel, we found that pre-sensitization with doxorubicin resulted in the upregulated expression of the functional TRAIL receptor, DR5, in highly TRAIL-resistant HT-29 cells by Western blotting and qRT-PCR. Although neither individual treatment of doxorubicin nor TRAILPEG induced apoptosis, pre-sensitization with doxorubicin followed by PEG-TRAIL induced significant apoptosis through the activation of both extrinsic and intrinsic apoptotic pathways promoted by the cleavage of caspases 8, 9, and 3. DR5, but not DR4, was recruited to the TRAIL-induced Death-Inducing Signaling Complex (DISC) within HT-29 cells pre-sensitized with doxorubicin, suggesting a TRAIL/DR5 specific pathway in CRC. To maximize the therapeutic efficacy of the sensitizer in vivo, doxorubicin was encapsulated in tumor-homing hyaluronic acid nanoparticles (HAC/DOX). Confocal microscopy and HPLC analysis enabled us to observe the efficient uptake and biodistribution of HAC/DOX in tumor tissues from xenografted HT-29 cells. HAC/DOX effectively sensitized the xenograft tumor, bearing the highly TRAIL-resistant HT-29 cells to TRAIL-induced apoptosis through the upregulated expression of DR5 and activation of caspases. Our study suggests an innovative approach to overcome the inherent TRAIL-based therapeutic limitations by introducing long-acting TRAIL and a tumor-homing TRAIL sensitizer to induce cancer cell-specific apoptosis in TRAIL-resistant CRC, particularly in physiological conditions.

Citation Format: Yumin Oh, Maggie Swierczewska, Seulki Lee. Strategy to overcome inherent TRAIL-based therapeutic limitations. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4395. doi:10.1158/1538-7445.AM2015-4395
Abstract 4400: Anti-tumor activity of liposomal docetaxel prodrug MNK-010 on PC3 human prostate xenografts in mice
Authors: Fitch Richard M. , Wojdyla Jolette K. , Blackledge James A. , McGhee William D.
Published: August 2015

The anti-mitotic taxanes are one of the most important families of anticancer drugs that have broad anti-tumor activity and are widely used for a variety of human cancer types. However, the taxanes are limited by a number of serious pharmacological and toxicological effects, including dose limiting myelosuppression, neurotoxicity and serious hypersensitivity reactions. We are developing a unique delivery system for docetaxel, comprised of a PEGylated liposomal nanoparticle containing a prodrug of docetaxel to improve solubility, tolerability and increase efficacy through improved pharmacokinetics and biodistribution. In this study we evaluated the antitumor activity of MNK-010 on the growth of established human PC3 xenografts in male immunodeficient mice. This study tested the hypothesis that MNK-010 can provide greater efficacy than Taxotere (docetaxel) at equivalent maximum tolerated doses (MTD) in mice implanted with human PC3 tumor cells. Male nude mice bearing PC3 human prostate xenografts were given two or four intravenous (IV) doses of MNK-010, Taxotere or saline. Dosing intervals were twenty-one days for two cycles or every four days for four cycles. The doses of Taxotere and MNK-010 were based on maximum tolerated dose (MTD) or highest dose tested for a given dose interval. Tumor volume was measured twice per week using the Biopticon tumor imaging system and tumor volume data was analyzed to determine tumor growth delay and partial tumor regression. Survival analysis was conducted and median survival time determined. MNK-010 significantly (p <0.05) inhibited PC3 human tumor growth in nude mice at all dose regimens evaluated compared to saline and Taxotere treatment. MNK-010 delayed tumor growth up to 145 days, which was 59 days longer than Taxotere at its MTD. MNK-010 also partially regressed 90% - 100% of tumors in all dose groups. This antitumor activity contributed to achieving median survival of 177 days, which was 150 days longer than saline control and 80 days longer than Taxotere at its MTD. This study demonstrated that Mallinckrodt Pharmaceuticals’ PEGylated liposomal docetaxel prodrug nanoparticle MNK-010 is an active antitumor agent in the PC3 prostate xenograft and possess significantly greater antitumor activity compared to the standard of care Taxotere.

Citation Format: Richard M. Fitch, Jolette K. Wojdyla, James A. Blackledge, William D. McGhee. Anti-tumor activity of liposomal docetaxel prodrug MNK-010 on PC3 human prostate xenografts in mice. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4400. doi:10.1158/1538-7445.AM2015-4400
Abstract 4401: Tumor-associated antigen gene-loading polyplex micelle is a promising platform for anti-cancer DNA vaccine
Authors: Cui Lin , Furugaki Kouichi , Osada Kensuke , Kataoka Kazunori , Nakano Kenji
Published: August 2015

Backgrounds: Polyplex micelle attracts an increasing attention as a gene carrier, because of efficient gene transduction and biocompatibility in vivo. In this study, we examined the potential of polyplex micelle carrying genes encoding tumor-associated antigen (TAA): squamous cell carcinoma antigen recognized by T cells-3, CD40L and GM-CSF as a DNA vaccine platform in mouse tumor models with different types of major histocompatibility antigen complex (MHC).

Methods and Results: Intraperitoneal administration of polyplex micelles were predominantly distributed and expressed in the lymph nodes, spleen and liver. The triple DNA vaccine significantly prolonged the survival of mice harboring peritoneal dissemination of CT26 colorectal cancer compared with mock controls, of which long-survivor mice induced complete rejection of re-challenged CT26 tumors. The DNA vaccine also inhibited the growth and metastasis of subcutaneous CT26 and Lewis lung cancers in BALB/c and C57BL/6 mice, respectively, which represent different MHC haplotypes. The DNA vaccine highly stimulated both cytotoxic T lymphocyte and natural killer cell activities, and increased the infiltration of CD11c+-DC, CD4+ and CD8a+ T cells into tumors. Depletion of CD4+ or CD8a+ cells using their neutralizing antibodies deteriorated the anti-tumor efficacy of the DNA vaccine.

Conclusions: TAA/CD40L+GM-CSF gene-loaded polyplex micelle is a novel vaccine platform to elicit tumor rejection immunity regardless of recipient's MHC-haplotype.

Note: This abstract was not presented at the meeting.

Citation Format: Lin Cui, Kouichi Furugaki, Kensuke Osada, Kazunori Kataoka, Kenji Nakano. Tumor-associated antigen gene-loading polyplex micelle is a promising platform for anti-cancer DNA vaccine. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4401. doi:10.1158/1538-7445.AM2015-4401
Abstract 4407: Novel mitochondria-targeted Doxorubicin Prodrug for colorectal cancer and hepatocellular carcinoma: In vitro studies
Authors: Jia Jemianne , Xing Minzhi , Ling Xiaoxi , Bai Mingfeng , Kim Hyun S.
Published: August 2015

Purpose:

The 18-kDa translocator protein (TSPO) in mitochondria is proapoptotic and upregulated in several types of cancers, particularly in colorectal cancer (CRC). This study aimed to develop a mitochondria-targeted doxorubicin prodrug and to investigate its cytotoxicity in human CRC (TSPO positive) and HCC (TSPO negative) cell lines.

Methods:

Mitochondria-targeted Doxorubicin Prodrug was synthesized by conjugation of a functional TSPO ligand with doxorubicin via an enzyme-cleavable linkage. Fluorescence cell viability assays in HT29, HCT116, HepG2 and Hep3B cells incubated with 5, 10, 25 and 50μM of Prodrug vs. Doxorubicin alone were performed using the CellTiter-Glo® Luminescent Cell Viability Assay (Promega, Madison, MI, USA) at 6, 12, 24, 48, 60 and 72 hrs. T-tests were used for all comparisons (significance <.05).

Results:

Significantly decreased cell viability in TSPO positive CRC cell lines (HCT116 and HT-29) with both the prodrug and doxorubicin vs. controls was observed (p<0.05). In HCT116, 10 and 25μM prodrug demonstrated significantly higher cytotoxicity vs. doxorubicin at 48 and 60 hrs, with plateau in effect at 72 hrs; 50μM prodrug had significantly higher cytotoxicity vs. doxorubicin alone at all time points (p<.05 for all). In HT-29, 25 and 50μM prodrug had significantly higher cytotoxicity vs. doxorubicin at 48 and 60 hrs (p<.05). In TSPO negative HCC cell lines (Hep3B and HepG2), prodrug and doxorubicin vs. control showed significantly decreased cell viability at all time points except for 10μM at 24 hrs; 25 and 50μM prodrug demonstrated similar cytotoxicity vs. doxorubicin at all time points except at 60 hours (p<.05 for all).

Conclusion:

Our novel mitochondria-targeted doxorubicin prodrug demonstrated superior cytotoxicity compared to doxorubicin in human CRC cell lines.

Citation Format: Jemianne Jia, Minzhi Xing, Xiaoxi Ling, Mingfeng Bai, Hyun S. Kim. Novel mitochondria-targeted Doxorubicin Prodrug for colorectal cancer and hepatocellular carcinoma: In vitro studies. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4407. doi:10.1158/1538-7445.AM2015-4407
Abstract 4432: A-803467, a tetrodotoxin-resistant sodium channel blocker, modulates ABCG2-mediated MDR in vitro and in vivo
Authors: Anreddy Nagaraju , Patel Atish , Zhang Yun-Kai , Wang Yi-Jun , Shukla Suneet , Kathawala Rishil J. , Kumar Priyank , Gupta Pranav , Ambudkar Suresh V. , Wurpel John ND , Chen Zhe-Sheng
Published: August 2015

ABCG2 is a member of the ABC transporter superfamily, which has been implicated in the development of multidrug resistance (MDR) in cancer. Its diverse range of substrates includes many antineoplastic agents such as topotecan, doxorubicin and mitoxantrone. ABCG2 expression has been significantly increased in some solid tumors and hematologic malignancies, which is correlated to poorer clinical outcomes. In addition, ABCG2 expression is a distinguishing feature of cancer stem cells, whereby this membrane transporter impacts resistance to the chemotherapeutic drugs. To enhance the chemosensitivity of cancer cells, attention has been focused on MDR modulators. In this study, we investigated the ability of a tetrodotoxin-resistant sodium channel blocker, A-803467 to reverse ABCG2-mediated MDR. We found that A-803467 at non-toxic concentration could significantly increase the cellular sensitivity to ABCG2 substrates in drug-resistant cells overexpressing either wild-type or mutant ABCG2. Mechanistic studies indicated that A-803467 (7.5 μM) significantly increased the intracellular accumulation of mitoxantrone by inhibiting the transport activity of ABCG2, without altering its expression level. In addition, A-803467 stimulated the ATPase activity of ABCG2 in a concentration-dependent manner, indicating that A-803467 might be a substrate of ABCG2. Binding interactions of A-803467 were found to be in transmembrane region of homology modeled human ABCG2. Interactions of A-803467 with ABCG2 were relatively stronger when compared to the interactions of topotecan with ABCG2. Furthermore, A-803467 (30 mg/kg) with topotecan (3 mg/kg) significantly decreased the growth rate and tumor size of ABCG2 overexpressing tumors in a xenograft nude mouse model. Our findings indicate that A-803467 has the potential to be used in combination with ABCG2 chemotherapeutic substrates to improve the response in drug resistant cancers.

Citation Format: Nagaraju Anreddy, Atish Patel, Yun-Kai Zhang, Yi-Jun Wang, Suneet Shukla, Rishil J. Kathawala, Priyank Kumar, Pranav Gupta, Suresh V. Ambudkar, John ND Wurpel, Zhe-Sheng Chen. A-803467, a tetrodotoxin-resistant sodium channel blocker, modulates ABCG2-mediated MDR in vitro and in vivo. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4432. doi:10.1158/1538-7445.AM2015-4432
Abstract 4477: A 5-nitrobenzoate-derived compound elicits anti-cancer metastatic activity by inhibition of poloplanin-stimulated tumor cell-induced platelet aggregation
Authors: Chang Yao-Wen , Hsieh Pei-Wen , Chong Kowit-Yu , Tseng Ching-Ping
Published: August 2015

Tumor cells dissemination and survival within the vascular system play an important role in cancer metastasis and is a clinical challenge for post-surgical cancer management. Podoplanin (PDPN) is one of the frequently over-expressed proteins in squamous cell carcinoma. By binding to platelet C-type lectin-like receptor 2 (CLEC-2), PDPN stimulates tumor cell-induced platelet aggregation (TCIPA) and facilitates cancer cell metastasis. In this study, a series of 5-nitrobenzoate-derived compounds were synthesized to screen for anti-cancer metastasis compounds that elicit functional blockage of PDPN-stimulated CLEC-2 activation and TCIPA. Platelet aggregation assays indicate that the small molecule compound 2CP selectively inhibited PDPN-induced platelet aggregation and the TCIPA of C6/Lung and osteosarcoma cells which expressed high levels of PDPN protein. Mouse tail bleeding time assay revealed that 2CP did not cause deleterious effects on normal blood hemostasis. In xenograft experimental metastasis model, 2CP possessed in vivo anti-cancer metastatic activity and augments the therapeutic efficacy of cisplatin; both the formation of pulmonary tumor foci and the body weight loss associated with the increased tumor burden were attenuated by combined treatment of 2CP and cisplatin. In conclusion, we present a novel and non-cytotoxic small molecule compound 2CP that elicits specific inhibitory effects on tumor cells-platelet interaction through intervening PDPN/CLEC-2 interaction and PDPN-mediated TCIPA. The findings are valuable for future application of 2CP in the prevention and treatment of cancer metastasis.

Citation Format: Yao-Wen Chang, Pei-Wen Hsieh, Kowit-Yu Chong, Ching-Ping Tseng. A 5-nitrobenzoate-derived compound elicits anti-cancer metastatic activity by inhibition of poloplanin-stimulated tumor cell-induced platelet aggregation. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4477. doi:10.1158/1538-7445.AM2015-4477