bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4451: Novel orphan G-protein-coupled receptor is oncogenic and mediates anti-estrogen resistance in human mammary carcinoma
Authors: Lee Yu Jin , Shin Kyeong Jin , Park Soo-Ah , Ryu Sung H. , Suh Pann-Ghill
Published: May 2015

Alterations in cellular pathways related to both endocrine and angiogenic factors may contribute to breast cancer progression. Inhibition of the elevated levels of these pathways is associated with clinical benefits. However, underlying mechanisms by which endocrine-related pathways and angiogenic factor signaling cooperatively promote breast cancer progression remain unclear. In this study, we report that novel orphan G-protein-coupled receptor (GPCR), GPR YJ, is oncogenic and mediates anti-estrogen resistance in breast cancer. GPR YJ is overexpressed in breast cancer cells and tissues, where elevated expression correlates with high tumor grade. Also, GPR YJ induces the expression of several angiogenic factors (VEGF, bFGF and IL-8), as well as ErbB (amphiregulin, epiregulin and neuregulins), which activate their respective pathways, leading to increased cell proliferation and survival, enhanced anchorage-independent growth, and promoted migration and invasion. In vivo, GPR YJ promotes the formation of large, well-vascularized tumors that metastasize to distant organs such as lymph nodes, lung and liver. Thus, deregulated expression of GPR YJ contributes to breast cancer progression and metastasis by inducing several growth factors that alter tumor-specific cell fates and the tumor stromal microenvironment.

Citation Format: Yu Jin Lee, Kyeong Jin Shin, Soo-Ah Park, Sung Ho Ryu, Pann-Ghill Suh. Novel orphan G-protein-coupled receptor is oncogenic and mediates anti-estrogen resistance in human mammary carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4451. doi:10.1158/1538-7445.AM2014-4451
Abstract 4453: Synergistic anticancer effect of combination of AZD6244 and BYL719 targeting KRAS mutant in non-small cell lung cancer
Authors: Jho Eun Hye , Kang Sin I. , Bae Yeon-Hee , Park Young Mee , Sun Jong-Mu , Ahn Jin Seok , Park Keunchil , Ahn Myung-Ju
Published: May 2015

KRAS mutation is found in 10-30% of non-small cell lung cancer (NSCLC) and highly correlated with smokers. So far, targeted agents demonstrating therapeutic activity against K-ras mutation are not available in a clinical setting. In this study, we show that dual agents, MEK inhibitor, AZD6244, and PI3K inhibitor, BYL719, have a synergistic effect on only KRAS mutant NSCLC cells. We defined that the combination of AZD6244 and BYL719 at ratios of IC50 1/2:1/2, 1:1, 2:2 (μM / μM) has ratio-dependent synergistic effect. In vitro, the combination of AZD6244 and BYL719 potently inhibited cell proliferation with cytotoxicity in H2009 and A549 cells more than the same cells treated with single drug. Also, BYL719 enhanced AZD6244-induced apoptosis and the combination treatment induced cleavage-PARP and Bim overexpression. In vivo, the antitumor efficacy was potentiated by co-treatment of AZD6244 and BYL719 in A549 xenografts. These data suggest that the combination of MEK and PI3K inhibitors might be a candidate for clinical development for its synergistic effect against KRAS-driven lung cancer.

Citation Format: Eun Hye Jho, Sin Il Kang, Yeon-Hee Bae, Young Mee Park, Jong-Mu Sun, Jin Seok Ahn, Keunchil Park, Myung-Ju Ahn. Synergistic anticancer effect of combination of AZD6244 and BYL719 targeting KRAS mutant in non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4453. doi:10.1158/1538-7445.AM2014-4453
Abstract 4458: PDLIM2 is essential for feedback regulation of the B1 integrin-FAK-RhoA signalling pathway to maintain epithelial cell polarity and suppress transformation
Authors: Kiran-Deevi Ravi , Cox Orla T. , O'Connor Rosemary
Published: May 2015

PDLIM2 is a PDZ-LIM domain protein that regulates the stability of transcription factors (NFkB and STATs) in the nucleus. It is also associated with the cytoskeleton at cell adhesions and cell junctions and is required for polarized cell migration. PDLIM2 expression is suppressed by methylation in different cancers, but is strongly expressed in invasive breast cancer cells that have undergone an Epithelial Mesenchymal Transition (EMT). Moreover, PDLIM2 expression is associated with poor outcome in basal breast cancers and its expression can be enhanced by vitamin D-induced differentiation of breast cancer cells.

Since PDLIM2 expression repression may facilitate oncogenic transformation and its expression is modulated by the differentiation status of breast cancer cells we asked whether it is essential for maintaining a non-transformed epithelial phenotype. To address this we suppressed PDLIM2 in MCF10A cells and assessed the phenotype and mechanism in 3D Matrigel cultures. We found that PDLIM2 suppression is sufficient to disrupt cell polarization and acinar formation in Matrigel cultures. MCF10A cells with suppressed PDLIM2 formed spheres of proliferating cells that exhibited reduced apoptosis in the luminal space, compared to control acini with hollow or apoptotic lumina. Spheroids with suppressed PDLIM2 had increased expression of cell-cell adhesion proteins including E cadherin and β-catenin. Proteins associated with cell-matrix adhesion were also up-regulated, including activated beta 1 (β1) integrin, laminin, and fibronectin production. Interestingly, both the IGF-1 Receptor and RACK1, which scaffolds IGF-1R to β1 integrin, were increased, indicating a transformed phenotype. FAK and cofilin phosphorylation, and RhoA activity were also enhanced in spheroids with PDLIM2 suppressed compared to controls. Importantly, pharmacological inhibition of either FAK or Rho Kinase (ROCK) was sufficient to rescue the polarity defect and abrogate all the phenotypic changes in MCF10A cell spheroids caused by PDLIM2 suppression.

We conclude that PDLIM2 mediates feedback regulation of the β1-integrin signalling pathway through FAK and RhoA that is essential for maintenance of polarized breast epithelial acinar structures, and for suppression of uncontrolled proliferation and cellular transformation.

Citation Format: Ravi Kiran-Deevi, Orla T. Cox, Rosemary O'Connor. PDLIM2 is essential for feedback regulation of the B1 integrin-FAK-RhoA signalling pathway to maintain epithelial cell polarity and suppress transformation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4458. doi:10.1158/1538-7445.AM2014-4458
Abstract 4468: Tumor vasculature targeting using cell-specific thioaptamer decorated chitosan nanoparticle
Authors: Jiang Dahai , Mangala Lingegowda S. , Wang Hongyu , Wu Sherry , Rao Lokesh G. , Rodriguez-Aguayo Cristian , Pradeep Sunila , Volk David E. , Lopez-Berestein Gabriel , Sood Anil K.
Published: May 2015

Anti-angiogenesis targeted therapy using RNA interference is a powerful tool to inhibit tumor growth and metastasis Here, we developed chitosan/thioaptamer nanoparticles that are capable of cell-type specific binding and delivery of siRNA into tumor-associated endothelial cells Thioaptamer (TA) was created by partial substitution of oxygen with sulfur on the aptamer phosphate backbone at the 5′dA position to enhance binding affinity and stability A combinatorial DNA aptamer library was established for cell-based selection method known as SELEX (systematic evolution of ligands by exponential enrichment) Endothelial cells isolated from both human ovarian tumors and normal human ovarian tissues were used to screen for selective thioaptamers After 10 cycles of cell-SELEX, two candidates, Endo28 and Endo31 showed highly specific binding to both human microvascular endothelial cells (HMVEC) and vasculature of human ovarian cancer tissue Endo28 decorated chitosan nanoparticles (CH/TA-siRNA) were ∼200 nm, positively charged (22mV), and spherical in shape The incorporation of thioaptamer Endo28 and siRNA to chitosan was confirmed using 1HNMR and PCR CH/TA-siRNA nanoparticles were intact and stable in the presence of serum at 37° C Intravenous administration of CH/TA nanoparticles into mice with HeyA8 ovarian tumors resulted in successful binding of aptamer to endothelial cells as well as delivery of siRNA into tumors TEM7 is a tumor biomarker found on the surface of endothelial cells TEM7 silencing using siRNA reduced endothelial tube formation and migration In orthotopic mouse models of ovarian cancer, murine TEM7 siRNA loaded nanoparticles showed substantial reduction in tumor growth as well as reduced angiogenesis These data have implications for new anti-angiogenesis approaches

Citation Format: Dahai Jiang, Lingegowda S. Mangala, Hongyu Wang, Sherry Wu, Lokesh G. Rao, Cristian Rodriguez-Aguayo, Sunila Pradeep, David E. Volk, Gabriel Lopez-Berestein, Anil K. Sood. Tumor vasculature targeting using cell-specific thioaptamer decorated chitosan nanoparticle. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4468. doi:10.1158/1538-7445.AM2014-4468
Abstract 4480: Double targeting nanoscale drug delivery system for treatment and imaging of metastatic solid cancers
Authors: Ahmed Md Shakir U. , Abdalla Mohamed O. , Turner Timothy
Published: May 2015

Purpose: As an alternative to the drawbacks of current advanced cancer treatments such as conventional chemotherapy, we propose a multifunctional double targeting drug delivery system that utilizes the combination of cancer-targeting peptides fused to amphiphilic polymer coated iron oxide nanoparticles (IONPs) and loaded with suitable anticancer drugs as the payload.

Methods: PC3 human prostate cancer cell line will be used initially to test the efficiency of the proposed drug delivery system. Our target sites of choice are the luteinizing hormone releasing hormone receptor (LHRH-R) and the urokinase-type plasminogen activator receptor (uPAR), and docetaxel was selected as the payload. A modified LHRH (ligand for LHRH-R) and AE105 (ligand for uPAR) were conjugated to polymer coated IONPs according to the manufacturer's protocol.

Results: Conjugated IONPs were characterized by gel electrophoresis and Dynamic Light Scattering (DLS). IONPs showed expected narrow size distribution after conjugation with peptide ligand. The average hydrodynamic size of non targeted IONPs (36.84 nm) was increased upon conjugation of double peptide to their surface (44.06 nm). Conjugation of peptides to carboxylic groups of polymer coating on IONPs resulted in a decrease of zeta potential from -70.43 mV to -58.06 mV. Prussian blue staining demonstrated that LHRH and AE105 conjugated IONPs were internalized efficiently by the PC3 cells. The drug loading and release capability of conjugated IONPs will be evaluated by HPLC. In addition the internalization of conjugated IONPs will also be examined utilizing Magnetic Resonance Imaging (MRI), and tumor eradication will be determined by MTT assay.

Conclusions: We expect a significant enhancement in the binding efficiency of the LHRH-IONPs-AE105 to the prostate cancer cells, increased efficiency in tumor eradication, and better imaging and monitoring capabilities because IONPs can be visualized by MRI during molecular imaging of the prostate cancer cells. Therefore, we believe the optimization of the proposed system will enhance targeted nanomedicine and significantly improve the health outcomes and quality of life for cancer patients because of the following reasons: 1) its ability to deliver anticancer drugs specifically to cancer cells while sparing the surrounding normal tissues, and 2) the capability of in situ monitoring of the therapeutics.

Citation Format: Md Shakir U. Ahmed, Mohamed O. Abdalla, Timothy Turner. Double targeting nanoscale drug delivery system for treatment and imaging of metastatic solid cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4480. doi:10.1158/1538-7445.AM2014-4480
Abstract 4489: Targeting cancer cells and antitumor effects of brucine immunonanoparticles on hepatocellular carcinoma in vivo
Authors: Qin Jianmin
Published: May 2015

Background: In vitro and in vivo studies have showed that brucine can inhibit the growth of liver cancer cells and animals with bearing cancer , and may be a promising anti-cancer drugs. However, high toxicity, poor water solubility, short half-life, narrow therapeutic window, close therapeutic and toxic dose limit its clinical application in malignant tumor treatment. In this study, we report on the preparation , in vivo distribution and antitumor effect of the brucine immuno-nanoparticles. Methods: Anionic polymerization and chemical modification technology was used to prepare carboxylated polyethylene glycol-poly lactic acid copolymer carrier material, phacoemulsification technology was employed to prepare carboxylated polyethylene glycol-polylactic acid copolymer brucine nanoparticles and chemical coupling technology was utilized to develop anti-human AFP McAb-polyethylene glycol-poly lactic acid copolymer brucine immuno-nanoparticles. The nude mice in situ transplanted liver cancer model was established by surgical technique, and the brucine immuno-nanoparcitles was injected by caudal vein at indicated time. The liver and kidney function and AFP level were assayed , and the anti-tumor effect was observed after intravenous administration of the brucine immuno-nanoparticles.

Results:This results showed that in vivo application of brucine immuno-nanoparticles caused temporary liver and kidney functions damage and significantly reduced AFP secretion. Brucine immuno-nanoparticles had good slow releasing and tumor targeting properties. The brucine immuno-nanoparticles inhibited CD34 expression and angiogenesis of tumor tissues, induced tumor apoptosis, and inhibited tumor growth.

Conclusions: The brucine immuno-nanoparticles has good tumor targeting and obvious anti-tumor effects , and is a promising targeted drug for liver cancer therapy in the future.

Note: This abstract was not presented at the meeting.

Citation Format: Jianmin Qin. Targeting cancer cells and antitumor effects of brucine immunonanoparticles on hepatocellular carcinoma in vivo. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4489. doi:10.1158/1538-7445.AM2014-4489
Abstract 4504: Urokinase plasminogen activator-dependent tumor penetrating peptide
Authors: Teesalu Tambet , Sugahara Kazuki N. , Braun Gary B. , Kotamraju Venkata Ramana , Ruoslahti Erkki
Published: May 2015

Activity of tumor penetrating peptides depends on C-end Rule (CendR) peptide motif (R/KXXR/K) that must be C-terminally exposed for tissue and cell penetration. We describe here a cryptic CendR peptide (uCendR; amino acid sequence: RPARSGR↓SAGGSVA) that is proteolytically activated by urokinase-type plasminogen activator (uPA), a protease overexpressed in human tumors. uPA cleavage unmasks the cryptic CendR element of uCendR peptide and triggers its binding and internalization to the neuropilin-expressing cultured cancer cells. Intradermally injected post-cleavage mimic of uCendR peptide (RPARSGR) increases permeability of skin microvessels to tracer compounds. Phage and silver nanoparticles functionalized with uCendR peptide in combination with angiogenic integrin-recruitment motif (CRGDC) home to tumor blood vessels, extravasate, and trigger vascular exit of co-injected tracer compounds. This study shows that modular tumor penetrating peptides that are specifically activated by a tumor derived protease can be developed for tumor-targeted drug delivery.

Citation Format: Tambet Teesalu, Kazuki N. Sugahara, Gary B. Braun, Venkata Ramana Kotamraju, Erkki Ruoslahti. Urokinase plasminogen activator-dependent tumor penetrating peptide. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4504. doi:10.1158/1538-7445.AM2014-4504
Abstract 4508: Engineering a single ubiquitin ligase for the selective degradation of all activated ErbB receptor tyrosine kinases
Authors: Li Hui
Published: May 2015

Interrogating specific cellular activities often entails the dissection of posttranslational modifications or functional redundancy conferred by protein families, which demands more sophisticated research tools than simply eliminating a specific gene product by gene targeting or RNA interference. We have developed a novel methodology that involves engineering a single SCFbTrCP-based ubiquitin ligase that is capable of not only simultaneously targeting the entire family of ErbB receptor tyrosine kinases for ubiquitination and degradation, but also selectively recruiting only activated ErbBs. The engineered SCFbTrCP ubiquitin ligase effectively blocked ErbB signaling and attenuated oncogenicity in breast cancer cells, yet had little effect on the survival and growth of non-cancerous breast epithelial cells. Therefore, engineering ubiquitin ligases offers a simple research tool to dissect the specific traits of tumorigenic protein families, and provides a rapid and feasible means to expand the dimensionality of drug discovery by assessing protein families or posttranslational modifications as potential drug targets.

Note: This abstract was not presented at the meeting.

Citation Format: Hui Li. Engineering a single ubiquitin ligase for the selective degradation of all activated ErbB receptor tyrosine kinases. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4508. doi:10.1158/1538-7445.AM2014-4508
Abstract 4516: Evaluation of p70S6K/Akt inhibitor MSC2363318A in patient derived xenograft (PDX) models of breast cancer
Authors: Huck Bayard R. , Tian H , Syed Sakeena , Lin Jing , Ma Jianguo , Clark Anderson , Kaleta Remiguisz , Machl Andreas , Wilker Erik , Lecomte Marc
Published: May 2015

The PI3K pathway is involved in the regulation of cell growth, proliferation, metabolism and other functions. Aberrant signaling (PTEN loss of function, PIK3CA mutation, Akt amplification, etc.) from the PI3K pathway is observed in >50% of all tumors. Clinical evidence suggests that inhibiting the PI3K pathway is beneficial for the treatment of solid tumors and tumors of the hematopoietic system. Inhibition of mTOR via rapalogs has been shown to block a negative feedback loop, thereby leading to the activation of Akt. The activation of this Akt feedback loop has been suggested to potentially compromise the clinical efficacy of selective mTORC1 inhibitors such as temsirolimus and everolimus. Dual p70S6K/Akt inhibition may promote improved pathway inhibition and also block the negative consequences of Akt activation through the negative feedback loop.

MSC2363318A is a highly selective, potent, adenosine triphosphate (ATP) competitive inhibitor of p70S6K, Akt1, and Akt3. In a cellular context, inhibition of p70S6K leads to potent inhibition of ribosomal protein S6 phosphorylation, while inhibition of Akt activity blocks the negative effects of a compensatory feedback loop. In addition, MSC2363318A exhibits potent anti-proliferative activity against many solid tumor cell lines in vitro, especially those with PI3K pathway genomic alterations. Further, MSC2363318A can also cross the blood-brain barrier (via pre-clinical studies in mice, rat, and dog), a unique characteristic that would allow for treating not only malignancies that are driven by PI3K pathway genomic alterations, but also indications with a high incidence of CNS metastases and primary malignancies of the central nervous system.

Patient Derived Xenograft (PDX) models from breast cancers with a high prevalence of PI3K pathway genomic alterations; including, triple negative breast cancer and Her2+ breast cancer were evaluated. In addition, combinations with standard of care agents were then evaluated in these breast cancer PDX models. Results from these studies were correlated with PI3K pathway genomic modifications, and will be used to guide subsequent clinical studies.

Citation Format: Bayard R. Huck, H Tian, Sakeena Syed, Jing Lin, Jianguo Ma, Anderson Clark, Remiguisz Kaleta, Andreas Machl, Erik Wilker, Marc Lecomte. Evaluation of p70S6K/Akt inhibitor MSC2363318A in patient derived xenograft (PDX) models of breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4516. doi:10.1158/1538-7445.AM2014-4516
Abstract 4517: Evaluation of the TOR kinase inhibitor CC214-2 in a mouse model of hormone-refractory prostate cancer
Authors: Yang Wenqing , Jiu Jing , Narla Rama Krishna , Raymon Heather K.
Published: May 2015

Prostate cancer is one of the most common malignancy diagnosed in men. Although androgen deprivation therapy is effective at the beginning of treatment, the majority of patients eventually progress to hormone refractory prostate cancer (HRPC), which leads to a poor outcome. HRPC mouse models have been developed to study transition from hormone dependent (HD) to hormone refractory (HR) disease; however, the exact mechanism behind this phenotypic conversion remains unclear. By using serial in vivo transplantation of LNCap xenograft tumors in castrated male SCID mice, we developed, validated and characterized a mouse model of HRPC, HR-LNCap. In vivo passaged tumor fragments form solid tumors in castrated male SCID mice. By comparison, HR-LNCap tumors grow more aggressively than parental LNCap tumors in SCID mice. A tumor cell line established from HR-LNCap xenograft tumors was able to grow in charcoal stripped serum containing medium, indicating it is androgen independent. HR-LNCap tumors lost sensitivity to androgen receptor antagonist bicalutamide, but remained sensitive to MDV-3100, a second generation AR antagonist approved for treating HRPC. Characterization of this model revealed that HR-LNCap tumors had unique AR signaling pathway profiles, including elevated AR expression and decreased expression of the AR-regulated genes, prostate specific antigen (PSA) and FKBP5, when compared with parental LNCap tumors. RNA sequencing was performed on HR-LNCap tumors to determine expression signature of the model. Interestingly, additional pathway analysis showed that HR-LNCap tumors have significantly higher levels of pAKT in comparison with parental LNCap tumors, indicating activation of AKT/mTOR pathway. Treatment of HR-LNCap tumor bearing mice with a small molecule TOR kinase inhibitor CC214-2 showed significant tumor growth inhibition. Further analysis demonstrated that treatment with CC214-2 inhibited TORC1 and TORC2 pathway markers, pAKT, pS6 and p4EBP1, in HR-LNCap tumors. Taken together, this study describes a mouse model of HRPC with a unique molecular profile, which can be used to evaluate novel therapeutics against HRPC.

Citation Format: Wenqing Yang, Jing Jiu, Rama Krishna Narla, Heather K. Raymon. Evaluation of the TOR kinase inhibitor CC214-2 in a mouse model of hormone-refractory prostate cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4517. doi:10.1158/1538-7445.AM2014-4517
Abstract 454: TET2 alterations facilitate progression of metastatic prostate cancer
Authors: Nickerson Michael L. , Das Sudipto , Lou Hong , Li Hongchuan , Turan Sevilay , Im Kate , Anderson Stephen , Andresson Thorkell , Dean Michael
Published: May 2015

Metastatic prostate cancer (mPCa) is a highly lethal disease and molecular markers identifying disease subtypes and/or therapeutic targets are needed. We sequenced the exomes of five metastatic tumors and healthy kidney tissue from an index patient with castration resistant mPCa to identify lesions associated with disease progression and metastasis. A somatic missense TET2 alteration predicted to be deleterious to the protein was observed at the metastatic stage of disease. We sequenced TET2 in additional mPCa tumors and PCa cell lines and detected somatic missense alterations, frequent LOH, and a frameshift truncation in PCa cell line, DU-145, derived from a mPCa brain tumor. We also observed complex combinations of frequent and rare germline missense SNPs, which may contribute to a previously described association of TET2 with PCa risk by GWAS. In this study, we confirm transcription factor binding to TET2 alleles associated with disease by GWAS. We examine TET2 binding partners in prostate cells by affinity purification, mass spectrometry, and forward and reverse immunoprecipitation. We confirmed a protein complex containing TET2, OGT, and two transcriptional co-activators/splicing factors implicated in receptor-mediated gene expression. Functional analysis shows TET2 loss alters expression of a unique set of genes, increases cell proliferation, and therefore is a driver of PCa. TET2 loss may facilitate progression to castration resistant mPCa and appears to define a subset of cases with metastatic disease.

Citation Format: Michael L. Nickerson, Sudipto Das, Hong Lou, Hongchuan Li, Sevilay Turan, Kate Im, Stephen Anderson, Thorkell Andresson, Michael Dean. TET2 alterations facilitate progression of metastatic prostate cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 454. doi:10.1158/1538-7445.AM2014-454
Abstract 4547: Enhanced anti-tumor effect of WNT pathway antagonists in combination with taxanes
Authors: Yen Wan-Ching , Fischer Marcus M. , Lewicki John , Gurney Austin , Hoey Timothy
Published: May 2015

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 previously demonstrated that inhibition of WNT/beta-catenin signaling by vantictumab (anti-FZD) or OMP-54F28 (FZD8-Fc) inhibits tumor growth, decreases tumorigenicity and induces differentiation in solid tumors. The anti-tumor effect of our Wnt antagonists is most evident in combination with chemotherapeutic agents. We sought to determine if the anti-tumor effect of Wnt pathway inhibitors varied with different chemotherapeutic agents. We compared the growth inhibitory effect of vantictumab and OMP-54F28 with either taxanes (paclitaxel and nab-paclitaxel) or with DNA synthesis inhibitors (gemcitabine and carboplatin) in patient-derived tumor xenografts. In a model for pancreatic ductal carcinoma, vantictumab with nab-paclitaxel was more efficacious than vantictumab with gemcitabine in inhibiting tumor growth and Wnt target gene expression (at doses of nab-paclitaxel and gemcitabine that were equivalent in their single-agent growth-inhibitory effects). Histologic analysis indicated that nab-paclitaxel increased mitotic cells and beta-catenin levels. Importantly, the addition of vantictumab to nab-paclitaxel reversed the nab-paclitaxel-induced increase in mitotic cells and beta-catenin expression. An independent experiment in a serous ovarian cancer xenograft model also showed enhanced anti-tumor activity when combining OMP-54F28 with either paclitaxel or nab-paclitaxel compared to the combination with carboplatin. A potential mechanism to account for these results involves on the observation that Wnt/beta-catenin signaling is under cell cycle control and peaks at the G2/M phase. Taxanes inhibit microtubule function and block the cell cycle at G2/M. In contrast, other chemotherapeutic agents, such as platinum compounds and nucleoside analogs, inhibit DNA synthesis and block cell proliferation at S phase. We hypothesize that combination of Wnt blockade with chemotherapeutic agents, such as taxanes, that induce G2/M arrest may result in optimal anti-tumor activity.

Citation Format: Wan-Ching Yen, Marcus M. Fischer, John Lewicki, Austin Gurney, Timothy Hoey. Enhanced anti-tumor effect of WNT pathway antagonists in combination with taxanes. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4547. doi:10.1158/1538-7445.AM2014-4547
Abstract 4566A: Effect of the anti-histaminic cyproheptadine on cell cycle of hepatocellular carcinoma cells and its mechanisms
Authors: Hsu Cheng-Da , Feng Yu-Min , Chen Syue-Yi , Feng Jing-Wen
Published: May 2015

Hepatocellular carcinoma (HCC) is a major cause of cancer deaths worldwide; however, current chemotherapeutic drugs for hepatocellular carcinoma (HCC) are either poorly effective or expensive. The majority of patients can't have good outcomes by taking these drugs. Currently, we had a breakthrough finding in a case report of two patients with advanced HCC. We found one had complete remission of liver tumors, one had decrease of their alpha-fetoprotein levels and that both their lung metastasis had complete remission after the concomitant use of thalidomide and cyproheptadine. In light of a previous study that cyproheptadine affects the cell cycle and impedes leukemia cell growth by suppressing the action of transcription factor of cyclin D, we assume that cyproheptadine is the key factor in this treatment. Therefore, the purpose of this study was to investigate whether cyproheptadine inhibits HCC cell growth by impeding cancer cell cycle and to explore the molecular mechanisms of cyproheptadine-induced cell cycle arrest. First, we confirmed that cyproheptadine had inhibition effect on two HCC cell lines, HepG2 and Huh-7, by cell viability assay. Besides, to explore how cyproheptadine affects HCC cell cycle we analyzed DNA content by flow cytometry and found cell cycle arrest at the G1 to S transition in HepG2 cells and at the S to G2 transition in Huh-7 cells. Finally, we investigated the mechanism of cyproheptadine-induced cell cycle arrest using western blot analysis. Interestingly, our results showed that cyproheptadine promoted P38 activation by phosphorylation than subsequently stabilized P16 and caucused hypophosphorylation of Rb in HepG2 cells. On the other hand, cyproheptadine not only promoted P38 activation but also activated ATM/Chk2 pathway to stabilize P21 in Huh-7 cells. These novel results demonstrated that cyproheptadine suppressed HCC cells through the Non-classical P38 MAP Kinase Functions: Cell Cycle Checkpoints and ATM/Chk2 pathway, and provided a potential treatment option in HCC.

Citation Format: Cheng-Da Hsu, Yu-Min Feng, Syue-Yi Chen, Jing-Wen Feng. Effect of the anti-histaminic cyproheptadine on cell cycle of hepatocellular carcinoma cells and its mechanisms. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4566A. doi:10.1158/1538-7445.AM2014-4566A
Abstract 4582: CRLX522, a novel dynamic tumor-targeted cabazitaxel nanopharmaceutical
Authors: Lazarus Douglas , Kabir Sujan , Eliasof Scott
Published: May 2015

Cabazitaxel is an approved treatment for castration-refractory prostate cancer. As with other taxanes, the therapeutic benefits of cabazitaxel are often compromised by immunosuppression and neurotoxicity. In order to address the obstacles to using cabazitaxel, we developed the dynamic tumor-targeted cabazitaxel nanopharmaceutical CRLX522. This nanopharmaceutical possesses significantly enhanced efficacy and improved pharmacokinetics compared to the parent drug. CRLX522 showed a superior PK profile, with a >400-fold increase in AUC, a significantly longer half-life and a 32-fold higher drug concentration in tumor tissue 72 hours after a single administration versus cabazitaxel alone. The improved PK and biodistribution of CRLX522 translated into superior antitumor activity in murine syngeneic and human xenograft models. In the murine B16.F10 tumor model, median survival at the MTD exceeded 58 days for CRLX522 compared to 26 days for the parent drug cabazitaxel. CRLX522 demonstrated superior efficacy over cabazitaxel with a cure rate of 100% in a xenograft model representing breast cancer tumors, compared to 50% cures for the parent drug cabazitaxel. In summary, CRLX522 represents a new and potent anticancer therapeutic that has the potential to be a best-in-class taxane.

Citation Format: Douglas Lazarus, Sujan Kabir, Scott Eliasof. CRLX522, a novel dynamic tumor-targeted cabazitaxel nanopharmaceutical. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4582. doi:10.1158/1538-7445.AM2014-4582
Abstract 459: The function of FOXO1 in the late phases of the cell cycle is suppressed by PLK1-mediated phosphorylation
Authors: Yuan Chengfu , Wang Lei , Zhou Liang , Fu Zheng
Published: May 2015

Polo-like kinase 1 (PLK1) plays crucial roles in multiple stages of cell division. Our previous studies suggest that global transcriptional regulation by PLK1 may contribute to its multiple functions. PLK1 depletion is associated with a decrease in cell viability and the induction of apoptosis; however, the underlying mechanisms are not completely understood. Here, we report that forkhead box protein O1 (FOXO1) is a novel physiological substrate of PLK1. FOXO1 is at the interface of crucial cellular processes, orchestrating programs of gene expression that regulate apoptosis, cell cycle progression, and oxidative-stress resistance. PLK1 interacts with and phosphorylates FOXO1, mainly at the G2/M phase of the cell cycle. PLK1-mediated phosphorylation leads to the impairment of FOXO1's transcriptional activity in an Akt-independent manner. By immunofluorescence staining and subcellular fractionation, we demonstrate that PLK1-induced FOXO1 phosphorylation causes its nuclear exclusion. Furthermore, PLK1-mediated phosphorylation of FOXO1 negatively regulates its pro-apoptotic function, and abrogates its ability to delay entry into and progression through G2/M transition. Therefore, our results suggest that PLK1 abrogates the inhibitory effects of FOXO1 on cell growth and survival to ensure timely cell cycle progression. This study not only reveals a novel and major regulatory mechanism of FOXO1 at the late phases of the cell cycle, but also provides new insight into the molecular mechanisms by which PLK1 inhibition leads to growth arrest and cell death.

Note: This abstract was not presented at the meeting.

Citation Format: Chengfu Yuan, Lei Wang, Liang Zhou, Zheng Fu. The function of FOXO1 in the late phases of the cell cycle is suppressed by PLK1-mediated phosphorylation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 459. doi:10.1158/1538-7445.AM2014-459
Abstract 4594: Reversal of Warburg effect by Apigenin and 5-Fluorouracil loaded dual drug liposomes result in enhanced colorectal chemotherapy
Authors: Sen Kacoli , Banerjee Shubhadeep , Mandal Mahitosh
Published: May 2015

Recent combinatorial approaches have demonstrated multidrug-based chemotherapy which target multiple pathways simultaneously leading to enhanced efficacy and reduced toxicity. Our study reports simultaneous delivery of 5-Fluorouracil (a clinically approved drug) and Apigenin (a naturally occurring isoflavonoid abundantly present in fruit and vegetables) through a single liposome to combat and control colon cancer effectively in-vitro and in-vivo based on synergy studies after screening natural product library. Uniform homogeneous suspension of dual drug-loaded large unilamellar vesicles with substantial entrapment of both drugs was obtained by modified thin film hydration method. The vesicles exhibited excellent hemocompatibility and cytocompatibility against normal fibroblasts. The cytotoxicity and cellular effects of individual and combinatorial free drugs, neat vesicles and single or dual drug-loaded liposomes tested against different human colon cancer cell lines revealed significantly higher cytotoxicity of dual-drug liposomes in comparison to other formulations. The dual drug loaded liposomal formulation was observed to be effectively internalized by endocytosis and demonstrated enhanced inhibition of angiogenesis, better reduction in cell proliferation, increased apoptotic potential and significantly decreased cellular migration and invasion capacity. Cell signaling studies indicating a significant upregulation of AMPK and activity against downstream targets by dual drug liposomes resulted in apoptosis, autophagy and senescence, suggesting its role in the reversal of Warburg effect. Enhanced apoptotic potential of the formulation was traced to its ability to induce greater oxidative stress through the generation of reactive oxygen and nitrogen species. The formulation was tested in a preclinical setting in nude mice tumor xenograft model and was found to have greater anti-neoplastic and anti-tumorigenic effect. The study indicated the potential of the synergistic effect of Apigenin in 5-Fluorouracil treatment of colon cancer which effectively circumvents the problem of drug resistance and 5-Fluorouracil associated toxicity. This dual drug loaded liposomal formulation thus, offers a new attractive alternative to enhance the therapeutic potency of drugs and paves way for potential clinical applications.

Note: This abstract was not presented at the meeting.

Citation Format: Kacoli Sen, Shubhadeep Banerjee, Mahitosh Mandal. Reversal of Warburg effect by Apigenin and 5-Fluorouracil loaded dual drug liposomes result in enhanced colorectal chemotherapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4594. doi:10.1158/1538-7445.AM2014-4594
Abstract 4595: RPL18A as putative target of rigosertib
Authors: Oussenko Irina , Divakar Saikrishna , Reddy M. V. Ramana , Holland James F. , Reddy E. Premkumar , Ohnuma Takao
Published: May 2015

Rigosertib (ON 01910.Na) is clinical stage anti-mitotic cancer inhibitor that causes spindle abnormalities in neoplastic cells. Rigosertib inhibits PI3K and PLK1 signaling pathways, down regulates cyclin D1 expression and induces apoptosis. Previously we reported rigosertib led to hyperphosphorylation of RanGAP1•SUMO1, regulator of RanGTP/RanGDP cycle, and hypothesized phosphatase inhibition [Cancer Res 2011; 71; 4968-76]. Using biotin-conjugated rigosertib and avidin-conjugated agarose beads, we sought rigosertib molecular target from HeLa cell lysates by pull-down assay. Long-linker 1910-biotin showed an IC50 for cytotoxicity similar to unmodified rigosertib and efficient avidin binding. Asynchronously grown HeLa cell lysates were incubated with designated ligands and avidin beads. Bound lysate proteins were recovered from beads, resolved on SDS-PAGE and stained. Specific protein band of ∼20 kDa was detected only with long-linker 1910-biotin. Identification of proteins from the gel was performed by LC-ESI-MS/MS. Four ribosomal proteins possessed Mascot score above cut-off level with RPL18A, score of 367, and other proteins scored 153 or less. Specific dose-dependent binding of long-linker 1910-biotin to RPL18A was confirmed by Western blot analysis in replicate pull-down experiments using HeLa or MOLT-3 cell lysates. Recombinant RPL18A possessed specific reactivity to 1910-biotin in the pull-down assay. Knock-down of RPL18A with siRNA causes apoptosis in cancer cell lines [Sudo et al, Genomics 2010; 95; 210-6; and our data]. We propose that nucleocytoplasmic transport of RPL18A is impaired when hyperphosphorylated RanGAP1•SUMO1 fails to provide RanGTP/GDP gradient for nuclear pore complex. Importin-9 (IPO-9) is a major nucleocytoplasmic transporter for RPL18A. Among other cargos of IPO-9 are HSP27 (important anti-apoptotic player), scaffold subunit A of PP2A (major mitotic phosphatase), core histones and ribosomal proteins. Considering the essential role of nucleocytoplasmic transport in general and probable consequences of impeded transport of HSP27, PP2A and/or core histones, that actually match those observed with rigosertib, we hypothesize that binding with RPL18A in the presence of hyperphosphorylated RanGAP1•SUMO1 interferes with normal function of IPO-9, resulting in a variety of malfunctions and apoptosis observed in rigosertib treated cancer cells.

Citation Format: Irina Oussenko, Saikrishna Divakar, M. V. Ramana Reddy, James F. Holland, E. Premkumar Reddy, Takao Ohnuma. RPL18A as putative target of rigosertib. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4595. doi:10.1158/1538-7445.AM2014-4595
Abstract 46: Loss of CADM1 expression is associated with poor prognosis and brain metastasis in breast cancer patients
Authors: Wikman Harriet , Westphal Laura , Schmid Felicitas , Glatzel Markus , Matschke Jakob , Westphal Manfred , Pollari Sirkku , Iljin Kristiina , Terracciani Luigi , Huhtala Heini , Kallioniemi Anne , Sauter Guido , Müller Volkmar , Witzel Isabell , Lamszus Katrin , Kemming Dirk , Pantel Klaus
Published: May 2015

Purpose: Breast cancer brain metastases (BCBM) are detected with increasing incidence. Therefore, identification of genes involved in BCBM formation is of great interest. Eperimental Design: In order to detect potential genes involved in BCBM, we first screened for genes down-regulated by methylation in cell lines with site-specific metastatic ability. The expression of five genes, CADM1, SPARC, RECK, TNFAIP3 and CXCL14, which were also found down-regulated in gene expression profiling analyses of BCBM tissue samples, were verified by qRT-PCR in a larger patient cohort. CADM1 was chosen for further down-stream analyses. Results: A higher incidence of CADM1 methylation, correlating with the expression levels, was found in BCBM as compared to non-matched primary BC. Similarly, loss of CADM1 protein expression was detected more commonly among BCBM samples as well as among primary breast tumors with subsequent brain relapse. The prognostic role of CADM1 expression was finally verified in two publicly available data sets (n=418) and in two large independent primary breast cancer TMA tumor cohorts (n=1718). The immunohistochemical analyses revealed an association between loss of CADM1 protein expression and risk factors such as disease stage, lymph node status, and tumor size in primary BC. Furthermore, all analyses revealed a significant association between CADM1 and shorter survival. In multivariate analyses, survival was significantly longer for patients with CADM1-positive primary tumors for both TMA data sets (p= 0.04 and p=0.01). Conclusions: Loss of CADM1 expression is an independent prognostic factor especially associated with the development of brain metastases in breast cancer patients.

Citation Format: Harriet Wikman, Laura Westphal, Felicitas Schmid, Markus Glatzel, Jakob Matschke, Manfred Westphal, Sirkku Pollari, Kristiina Iljin, Luigi Terracciani, Heini Huhtala, Anne Kallioniemi, Guido Sauter, Volkmar Müller, Isabell Witzel, Katrin Lamszus, Dirk Kemming, Klaus Pantel. Loss of CADM1 expression is associated with poor prognosis and brain metastasis in breast cancer patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 46. doi:10.1158/1538-7445.AM2014-46
Abstract 4615: Influence of SF3B1 gene mutation is different from that of Sf3B1 inhibitor in colorectal cancer
Authors: Yamano Tomoki , Kubo Shuji , Matsubara Nagahide , Yano Aya , Tomita Naohiro
Published: May 2015

Purpose: We have reported that SF3B1 gene mutations are rare in colorectal cancer patients and SF3B1 gene mutations in codon 1074 are responsible for resistance to SF3B1 inhibitor (FR901464, FR) at the AACR annual meeting 2013. SF3B1 gene mutations in hematological malignancies are considered to be related to tumor progression. To elucidate the influence by SF3B1 gene mutation in colorectal cancer, we assessed the tumor growth of colorectal cancer cells bearing SF3B1 gene mutation in vitro and in vivo.

ExperimentalDesign: We assessed the tumor growth in vitro and in vivo using FR resistant clones (DLD/FR1, DLD/FR2, DLD/FR3, HCT/FR1, HCT/FR2, and LoVo/FR1) derived from DLD1, HCT116, and LoVo. We also performed microarray analysis of DLD1, DLD/FR1, HCT116, and HCT/FR1 with or without FR for 24 h to compare the change of gene expression by FR or SF3B1 gene mutation.

Results: Doubling time of growth in DLD/FR1, DLD/FR2, HCT/FR1, and HCT/FR2 in vitro was same as their parental cells. However, doubling time of growth in DLD/FR3 and LoVo/FR1 in vitro was longer than their parental cells. In mouse subcutaneous xenograft models, the tumor volume of DLD1/FR1, HCT/FR1, and HCT/FR2 were 61%, 32 %, and 25%, to compared to that of their parental DLD1 or HCT116 one month after inoculation, respectively. Microarray analysis showed the genes and pathways affected by SF3B1 inhibitor and SF3B1 gene mutation did not match at all. Though SF3B1 inhibitor strongly inhibited pathways related to cell cycle, Fanconi anemia, homologous recombination, ubiquitin mediated proteolysis, nucleotide excision repair, oocyte meiosis, basal transcription factors, and endocytosis, SF3B1 gene mutation did not influence these pathways. The genes influenced by SF3B1 gene mutations included MHC class I/II, MHC MYC, BCL2, IL2, and IL10.

Conclusion: Our data indicated SF3B1 gene mutation in colorectal cancer induced disadvantage in cancer progression by the different pathway from SF3B1 inhibitor.

Citation Format: Tomoki Yamano, Shuji Kubo, Nagahide Matsubara, Aya Yano, Naohiro Tomita. Influence of SF3B1 gene mutation is different from that of Sf3B1 inhibitor in colorectal cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4615. doi:10.1158/1538-7445.AM2014-4615