bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract C172: A synthetic glycolipid induces macrophage-mediated apoptosis of cancer cells via nitric oxide-dependent downregulation of thoc1 gene.
Authors: Lin Yong-Shiang , Lin Chao-Hsiung , Lin Chun-Cheng , Fu Shu-Ling
Published: June 2012

Activation of Toll-like receptor 4 (TLR4) triggers both innate and adaptive immunity. We previously developed a synthetic TLR4 agonist, CCL-34, which can induce anticancer immunity in vitro and in vivo. The CCL-34-activated macrophages were shown to induce nitric oxide (NO)-dependent apoptosis of cancer cells. In addition, the THO complex 1 (thoc1) gene was suppressed in cancer cells co-cultured with CCL-34-activated macrophages and in tumors of CCL-34-treated mice, suggesting the involvement of Thoc1 in the CCL-34-induced anticancer activity. It has been shown that Thoc1 promoted cell survival and was overexpressed in many cancer cells. However, regulation of thoc1 and its downstream effectors in Thoc1-mediated cell survival remains unknown. In this study, we investigated the role of Thoc1 in the cancer cell apoptosis induced by CCL-34-activated macrophages and the underlying molecular mechanisms. Our data showed that the suppressed Thoc1 in bladder cancer cells (MBT-2) co-cultured with CCL-34-activated macrophages was restored by iNOS inhibitor (L-NMMA), and direct treatment of MBT-2 cells with NO donor repressed Thoc1 expression. Moreover, treatment of either CCL-34 or NO donor resulted in the suppression of thoc1 promoter activity in MBT-2 cells, whereas mutations in certain region of this promoter region abolished such repression. Notably, MBT-2 cells overexpressing thoc1 (MBT/thoc1) exhibit higher resistance to the cytotoxicity induced by treatment of NO donor or CCL-34-activated macrophages than MBT-2 cells, while both treatments suppressed Bcl-2 expression in MBT-2 cells but not in MBT-2/thoc1 cells. Together, our results demonstrate that NO-mediated thoc1 downregulation is a key step in the cancer cell apoptosis induced by CCL-34- treated macrophages. In addition, the decreased expression of thoc1 could lead to downregulation of Bcl-2 and subsequent induction of cancer cell apoptosis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C172.
Abstract C191: Preclinical investigation of the antitumor efficacy in lung cancer of Y15, a novel focal adhesion kinase inhibitor.
Authors: Dy Grace K. , Shao Huanjie , Ho Baotran , Yemma Michael , Adjei Alex , Golubovskaya Vita , Cance William
Published: June 2012

Introduction: Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase that associates with a number of cell adhesion components, such as integrins, paxillin and talin, as well as with various signaling proteins such as phosphatidylinositol 3-kinase (PI3K) and the Src family of protein kinases. It thus plays an important role in cell motility, invasion, growth and cell survival. Y15 (1,2,4,5-benzentetraamine tetra hydrochloride) is a small molecule that inhibits FAK autophosphorylation by selectively targeting the Y397 phosphorylation site of FAK. It has shown activity against breast, colon and pancreatic cancers. We herein present data in lung cancer.

Methods: Various lung cancer cell lines as well as minimally passaged patient-derived tumor (containing PIK3CA mutation E545K) propagated in vitro were treated with escalating doses of Y15 or DMSO for 72 hours to evaluate single-agent activity. Cell lines were also treated with cytotoxic agents (cisplatin, gemcitabine, pemetrexed, paclitaxel) in combination with escalating doses of Y15. Cellular viability was assessed by trypan blue exclusion assay and colony formation assay. For in vivo experiments, selected cell lines were implanted into nude mice and vehicle versus Y15 treatment, via either intraperitoneal or oral gavage administration, once daily was started when tumors reached a mean volume of 50–60 mm3. Western blot will be performed to investigate alterations in the activity of various signaling proteins.

Results: Y15 exhibited time and dose-dependent cell death in 6 out of 9 lung cancer cell lines tested. Activity was demonstrated beginning at 4 uM dose, with almost 100% cell kill demonstrated at 10 uM dose. There was also corresponding dose-dependent loss of clonogenic ability starting at 1 uM dose in sensitive cell lines. In addition, Y15 enhanced paclitaxel-induced cell death. Mice treated with Y15 at 100 mg/kg oral gavage administration showed reduced tumor growth compared to control mice.

Conclusion: Y15 demonstrates promising antitumor efficacy against various non-small cell lung cancer cell lines. Further development of this agent in lung cancer is warranted.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C191.
Abstract C195: Inhibition of polo-like kinase 1 (PLK1) by BI 2536: Effects on mitotic index, clonogenic capacity, and proliferation in medulloblastoma cell lines.
Authors: Pezuk Julia Alejandra , Brassesco Maria Sol , Morales Andressa Gois , de Oliveira Jaqueline Carvalho , Scrideli Carlos Alberto , Bobola Michael S. , Tone Luiz Gonzaga
Published: June 2012

Medulloblastoma is the most common central nervous system tumor in childhood. Despite high survival rates (over 50% for most protocols) the treatment for this tumor usually results in severe sequels. Still, in patients younger than 3 years-old radiotherapy cannot be used turning the prognosis even worse. Polo-like kinase 1 (PLK1), a serine-threonine kinase that regulates mitosis progression, has been repeatedly associated with increased cell proliferation and poorer prognosis in several types of cancer. The aim of this study was to evaluate the effects of the inhibition of PLK1 with BI 2536 on mitotic index clonogenic capacity and cell proliferation, on the UW402 and UW473 pediatric medulloblastoma cell lines. Equal numbers of cells were treated with 50, 100 and 150 nM of BI 2536 for 24, 48 and 72 hours. To calculate the mitotic index cells after treatment dropped onto glass slides, allowed to air dry and stained with Giemsa, 1000 cells were counted. To calculated the clonogenic capacity cells were treated, let to grow for 7 days and then the colonies were fixed with methanol and stained with Giemsa. Only colonies with > 50 cells were counted. To analyze the proliferation cells after treatment were let with culture medium containing 10 μL of XTT dye (XTT II; Roche Molecular Biochemicals, Indianapolis, IN), plates were incubated for 2 hours at 37°C and the formazan product was measured at 450 nm by using an iMark microplate reader (Bio-Rad Laboratories). Each experiment was performed in triplicate wells and repeated in three sets of tests. The tests were analyzed by oneway ANOVA followed by Home-Sidak test. Values of p≤0.05 were considered statistically significant. The Inhibition of PLK1 by this drug showed an efficient decrease (p<0.05) on cell proliferation in dose- and time-dependent manner. The clonogenic assay also demonstrated that BI 2536 causes a significant reduction in colony formation at concentrations as low as 5nM (p<0.05). The mitotic index analysis showed a significant accumulation of dividing cells (p<0.05) with a more evident effect after 24h of treatment. Although further studies are needed, our results point to PLK1 as a potential target to improve medulloblastoma treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C195.
Abstract C201: The combination of the small molecule TGFβR1 inhibitor LY2157299 monohydrate with CCNU substantially blocks SMAD phosphorylation and significantly suppresses human glioblastoma xenograft growth.
Authors: Parsons Stephen , Sawyer Scott , Yan Lei , Foreman Robert , Weir Spring , Lahn Michael , Yingling Jonathan , Graff Jeremy R.
Published: June 2012

TGF-β signals through the type I and type II TGF-β receptors (TGFβRI and TGFβRII) to phosphorylate the SMAD proteins. In normal tissues, this signaling axis provides a growth inhibitory signal. However, in some cancers, TGF-β is often secreted at high levels and has been implicated in tumor invasion, angiogenesis and decreased immune surveillance. Recent work in GBM indicates that TGFβ may promote aggressive proliferation if the tumor cells are able to express Platelet Derived Growth Factor in response to TGFβ. Indeed, in glioblastoma patient samples, high pSmad2 levels are related to increased proliferation as well as reduced progression-free and overall patient survival. These data strongly implicate aberrant TGFβ signaling in human glioblastoma (GBM) and provide strong rationale to target this pathway for therapeutic intervention. Indeed, phase 1 and 2 clinical trials in GBM patients have begun using the recently developed small molecule inhibitor of TGFβR1 (LY2157299 monohydrate) alone and in combination with lomustine (CCNU). Herein, we show, in GBM cell lines, that LY2157299 monohydrate blocks signaling through the heteromeric TGFβ receptor complex to reduce levels of active, phosphorylated SMAD. Similarly, CCNU treatment of these same GBM cell lines also blocks Smad phosphorylation. In combination, CCNU and LY2157299 monohydrate more effectively block Smad phosphorylation than either agent alone. Furthermore, in U87MG and CRL-2611 human glioblastoma xenografts, oral dosing of LY2157299 monohydrate significantly enhanced the efficacy of CCNU (lomustine). Taken together, these preclinical data support the exploration of LY2157299 monohydrate in combination with CCNU for glioblastoma therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C201.
Abstract C21: A phase I trial of PR-104, a pre-prodrug of the bioreductive prodrug PR-104A, given weekly to solid tumor patients.
Authors: McKeage Mark , Gu Yongchuan , Wilson William R. , Hill Andrew , Amies Karen , Melink Teresa , Jameson Michael B.
Published: June 2012

Background: The phosphate ester PR-104 is rapidly converted in vivo to the alcohol PR-104A, a nitrogen mustard prodrug that is metabolised to hydroxylamine (PR-104H) and amine (PR-104M) DNA crosslinking agents by one-electron reductases in hypoxic cells and by aldo-keto reductase 1C3 independently of oxygen. In a previous phase I study using a q 3 week schedule of PR-104, the maximum tolerated dose (MTD) was 1100 mg/m2 and fatigue, neutropenic fever and infection were dose-limiting. The primary objective of the current study was to determine the dose-limiting toxicity (DLT) and MTD of weekly PR-104.

Methods, patients and treatment: Patients with advanced solid tumors received PR-104 as a 1-hour intravenous infusion on days 1, 8 and 15 every 28 days with assessment of pharmacokinetics on cycle 1 day 1. Twenty-six patients (pts) were enrolled (16 male/10 female; median age 58 yrs, range 30 to 70 yrs) who had received a median of two prior chemotherapy regimens (range, 0 to 3) for melanoma (8 pts), colorectal or anal cancer (3 pts), NSCLC (3 pts), sarcoma (3 pts), glioblastoma (2 pts), salivary gland tumors (2 pts) or other solid tumors (5 pts). PR-104 was administered at 135 mg/m2 (3 pts), 270 mg/m2 (6 pts), 540 mg/m2 (6 pts), 675 mg/m2 (7 pts) and 900 mg/m2 (4 pts) for a median of two treatment cycles (range, 1 to 7 cycles) and five infusions (range, 1 to 18) per patient.

Results: Dose-limiting toxicities (DLTs) during cycle one included grade four thrombocytopenia at 540 mg/m2 (1 of 6 pts) and grade four thrombocytopenia and neutropenia at 900 mg/m2 (2 of 4 pts). At an intermediate dose of 675 mg/m2, there were no DLTs among a total of seven patients given 12 treatment cycles but all experienced moderate to severe (grade 2 to 4) haematological toxicity. Thrombocytopenia was delayed in its onset and nadir, and its recovery was protracted and incomplete in many patients. There were no complete or partial tumor responses. PR-104-induced thrombocytopenia and neutropenia correlated with plasma AUC of PR-104, PR-104A and an oxidative semi-mustard metabolite (PR-104S1), but no more strongly than with PR-104 dose-level. There was no significant correlation between plasma AUC for the reduced metabolites and myelotoxicity.

Conclusions: Thrombocytopenia, and to a lesser extent neutropenia, was the DLT of weekly PR-104. The MTD was 675 mg/m2/week. PR-104 given weekly may be a suitable protocol for further clinical evaluation as a short course of treatment with fractionated radiotherapy or haematopoietic stem cell support, as its duration of dosing is restricted by delayed-onset and protracted thrombocytopenia.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C21.
Abstract C234: Decreasing ovarian tumor stromal signaling via SFRP2 mitigates ovarian cancer progression.
Authors: Thompson Melissa S. , Albitar Lina , Wong Kwong K. , Zaid Tarrik M. , Birrer Michael J. , Mok Samuel C.
Published: June 2012

The tumor microenvironment has been definitively shown to be a key player in tumor progression and metastasis in a variety of cancers, including ovarian cancer and provides a plethora of potentially significant therapeutic targets. As ovarian cancer is the deadliest gynecological disease due to a lack of reliable diagnostic testing and efficacious treatments, our objective was to determine how the ovarian cancer-associated fibroblasts (CAFs) are contributing to the propagation of ovarian cancer. Our lab has identified a distinct gene signature for the ovarian stromal component of high-grade late-stage (HGLS) serous ovarian cancer as compared to normal stroma, human ovarian surface epithelium, and ovarian tumor, and many of these genes are secreted proteins suggesting a paracrine role for the tumor microenvironment. Secreted frizzled related protein 2 (SFRP2), a protein integral to stemness and proliferation, is overexpressed in ovarian CAFs by over 10-fold. Quantitative RT-PCR and immunohistochemical staining validated the overexpression of SFRP2 in ovarian CAFs and also showed a clinical correlation for stromal SFRP2 overexpression with poorer overall survival and chemoresistance in patients with HGLS serous ovarian cancer. Furthermore, increased SFRP2 expression correlated with significantly higher microvessel density suggesting an angiogenic effect. In vitro functional studies illustrated increased ovarian cancer cell proliferation in response to recombinant SFRP2 that was dose and time dependent. Ovarian cancer cells overexpressing SFRP2 (autocrine signaling) also illustrated increased cell proliferation. Additionally, ovarian cancer cell co-cultured with ovarian CAFs induced increased SFRP2 expression in the CAFs. Using an allogenic mouse model, we determined that silencing stromal SFRP2 using a SFRP2 knockout mouse significantly decreased ovarian cancer cell growth, suggesting that eliminating tumor stromal signaling cues may mitigate ovarian cancer progression. Together, these results illustrate a direct and specific signaling linkage between ovarian tumor cells and their associated microenvironment, specifically CAFs, suggesting that elimination of this signaling linkage may slow ovarian cancer progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C234.
Abstract C237: Merkel cell polyomavirus infection-related Merkel cell carcinomas have intratumoral lymphocyte infiltrates and favorable survival.
Authors: Sihto Harri , Kukko Heli , Koljonen Virve , Sankila Risto , Salmi Marko , Jalkanen Sirpa , Bohling Tom , Joensuu Heikki
Published: June 2012

Introduction: Merkel cell carcinoma (MCC) is rare and often aggressive skin cancer that manifests mainly in elderly white people. The majority of MCCs contain Merkel cell polyomavirus (MCPyV) DNA. Patients with MCPyV-positive MCC have favorable survival as compared to those with MCPyV-negative tumor. The reasons for this remain speculative, but host immune defence might influence outcome of patients with MCPyV infection.

Material and Methods: Tumor infiltrating T-lymphocytes (CD3+ cells) and macrophages (CD68+ cells) were stained using immunohistochemistry from 116 MCCs. The numbers of stained cells were counted at 400× magnification of the microscope. Presence of MCPyV infection was assessed by detecting MCPyV DNA using quantitative PCR and the viral large T antigen using immunohistochemistry. The associations between the tumor immune cell counts, presence of MCPyV DNA, clinicopatholocial factors and patient survival were examined using the Mann-Whitney test and the Kaplan-Meyer survival analysis.

Results: MCPyV-positive tumors contained more CD3+ and CD68+ cells as compared to MCPyV-negative cancers (5.3 vs. 3.3 cells/high-power field [HPF], p=0.014; and 5.3 vs. 4.0 cells/HPF, p=0.028, respectively). Similar results were obtained when presence of MCPyV infection was efined by expression of the viral large T-antigen (5.9 vs. 2.7 cells/HPF, p<0.001; and 5.6 vs. 3.9 cells/HPF, p=0.003, respectively). Patients with regional nodal metastases had fewer CD3+ cells in the primary tumor as compared to those without metastases (2.3 vs. 5.3 cells/HPF, p=0.006). Patients who had MCC with a higher than the median number of CD3+ cells had better MCC-specific survival (55.2% vs. 82.1%, log-rank test p=0.003) and overall survival (22.4% vs. 50.0%, p=0.002) as compared to those with a smaller than the median tumor CD3+ cell count. Tumor CD3+ count was an independent prognostic factor for overall survival in a Cox multivariable analysis that included the presence of regional nodal etastases, gender and MCPyV large T-antigen expression as covariates (HR=0.55, 95% CI, 0.35 to 0.88, p=0.012). Conclusions: MCCs with evidence of MCPyV infection harbor high numbers of tumor infiltrating T-lymphocytes. A high number of CD3+ cells in the tumor is associated with generally favorable survival. Host immune response to MCPyV might explain in part the favorable survival associated with MCCs with MCPyV infection.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C237.
Abstract C241: Phase I trial of EUS-guided intratumoral vaccination with recombinant Panvac-F and systemic Panvac-V in patients with locally advanced pancreatic cancer.
Authors: Poplin Elizabeth A. , August David A. , Ben-Menachem Tamir , Michael Hazar , Artymyshyn Renee , Gulley James L. , Schlom Jeffrey , DiPaola Robert S. , Lattime Edmund C.
Published: June 2012

Preclinical studies in our laboratory were the first to demonstrate the superiority of intratumoral poxvirus vaccines in overcoming immune escape and effectively treating murine solid tumor models. We present here the translation of these findings to a Phase I trial in six patients with locally advanced inoperable adenocarcinoma of the pancreas (NCT00669734). The first dose cohort of patients were treated using a combination of EUS (Endoscopic Ultrasound)-guided intrapancreatic tumor injection of recombinant Panvac-F (Fowlpox encoding MUC-1, CEA, TRICOM, 108 PFU) in addition to systemic Panvac-V (vaccinia, 2 × 108 PFU) and Panvac-F (109 PFU) boosts (accompanied by subcutaneous rH-GM-CSF, 100 mcg × 4 days). Patients received a total of 2 intrapancreatic injections of Panvac-F (2 weeks apart) with systemic Panvac-V and Panvac-F boosts given with GMCSF extending to day 71 (total of 2 intrapancreatic Panvac-F, 1 sc Panvac-V, 4 sc Panvac-F). Patients were allowed to transition to standard care at day 31. Patients were evaluated for toxicity, tumor progression, and serum CA 19–9 and CEA levels. Two of six patients were removed from study after approximately two weeks due to rapid disease progression and died one and six months after trial initiation. Of the remaining four, one had received prior treatment with gemcitabine followed by capecitabine and radiation and received no further treatment after vaccination; three received post-vaccination standard treatment with gemcitabine. Of the 4 patients with followup of greater than 6 mos, all have clinically stable disease (15 mos, 13 mos, 12 mos, 9 mos). One pt had a DLT (pancreatitis) that resolved allowing completion of protocol therapy. Results demonstrate that the “first in human” intrapancreatic administration of the full recombinant poxvirus regimen was well tolerated with encouraging stable disease duration. The trial is currently accruing patients at intrapancreatic dose level 2 (109 PFU).

This study is supported by the NCI Cancer Therapy Evaluation Program (CTEP) and by NCI U01-CA07031 and P30-CA72720.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C241.
Abstract C27: Targeting ErbB3 and EGFR in lung cancer patients: A phase I trial of MM-121 in combination with erlotinib in patients with non-small cell lung cancer (NSCLC).
Authors: Sequist Lecia V. , Modiano Manuel , Rixe Olivier , Natarajan Chandra , Onsum Matthew , Kubasek William , Andreas Karen , Nering Rachel , Moyo Victor , Harb Wael A.
Published: June 2012

Background: The benefit of EGFR tyrosine kinase inhibitors (TKIs) is largely restricted to EGFR mutation-positive cancers and resistance invariably develops. A central theme of acquired resistance is persistent ErbB3 signaling, resulting in activation of the PI3K/AKT survival pathway. MM-121 is a fully human IgG1 monoclonal antibody (mAb) to ErbB3 with pre-clinical activity as a single agent and in combination with erlotinib in NSCLC, particularly in cancers with ligand-dependent activation of EGFR. This phase 1 study evaluated the safety and tolerability of MM-121 and erlotinib in NSCLC, as well as PK, immunogenicity, efficacy endpoints and exploratory biomarker evaluation.

Methods: Patients with advanced NSCLC, good performance status and adequate organ function were enrolled. Patients were EGFR TKI-naïve, unless they were EGFR mutant, in which case acquired resistance was allowed. MM-121 was administered weekly and erlotinib was administered daily. Seven cohorts were enrolled, evaluating varying dose levels of the combination, as well as alternate MM-121 infusion schedules. Dose levels were determined by safety and pharmacokinetic (PK) data.

Results: Between February 2010 and July 2011, 33 patients were enrolled. Median age was 64 years and there were 19 (57.5%) women. Twenty-four patients were erlotinib-naïve and 1 patient was an EGFR mutant. The most frequent adverse events were rash, diarrhea, nausea and fatigue. As of 31 July 2001, 16 patients remain on study. Full results will be presented at the meeting.

Conclusions: In this phase 1 dose escalation study, MM-121 plus erlotinib was well tolerated by the majority of patients. A phase 2 study is planned.

Reference: NCT00994123

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C27.
Abstract C37: Thromboxane synthase and COX-1 as drug targets to prevent systemic chemoresistance.
Authors: Voest Emile E. , Roodhart Jeanine , Daenen Laura M.G. , Houthuijzen Julia M.
Published: June 2012

Background: Chemotherapy remains the primary treatment for most disseminated cancers. However, the response to chemotherapy is often transient and development of resistance is one of the most significant obstacles to effective cancer therapy. Although various tumor-cell intrinsic mechanisms of drug resistance have been identified, it is becoming increasingly clear that the tumor micro-environment plays a key role in the development of drug resistance We recently identified two unique polyunsaturated fatty acids (PIFAs), 12-oxo-5,8,10-heptadecatrienoic acid (KHT) and hexadeca-4,7,10,13-tetraenoic acid (16:4(n-3)) that are produced by MSCs upon stimulation by platinum analogues (J. Roodhart, et al., Cancer Cell, in press). These PIFA render, at picomolar concentrations, tumors insensitive to various chemotherapeutics.

Aim: To prevent MSC-induced chemoresistance by blocking PIFA production through inhibition of tromboxane synthase (TxS) and cyclooxygenase (COX-1).

Method: Various mouse tumor models were used. Furthermore, cultured MSCs were treated with various drugs in order to block the release of PIFA. Conditioned media were subsequently analyzed in vivo.

Results: KHT, a by-product of thromboxane A2 synthesis, is a downstream product of the (COX)-1 and thromboxane synthase (TxS) pathway. Conditioned medium of platinum-activated MSC containing PIFA conferred resistance to various forms of chemotherapy in vivo. However, pretreatment of platinum-activated MSCs with SC-560, a highly selective COX-1 inhibitor, indomethacin, a relatively selective COX-1 inhibitor or one of two specific TxS inhibitors (ozagrel and furegrelate) did not induce chemoresistance in vivo. Of note, selective COX-2 inhibition in MSC by celecoxib did not affect their capacity to induce chemoresistance, suggestive of a specific COX-1/TxS-dependent PIFA production. When mice were treated with a combination of indomethacin or ozagrel and cisplatin tumor growth inhibition was improved and no tumor resistance was observed. Of note, no anti-tumor effect was observed of single agent indomethacin or ozagrel.

Conclusion: We show that blocking the release of PIFA from MSC during chemotherapy with agents that are clinically available improved the effectiveness of chemotherapy in vivo. These findings warrant further exploration in clinical trials.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C37.
Abstract C43: The impact of ADAM-9 protease activity on invasiveness of gastric cancer.
Authors: Kim Jeong Min , Rha Sun Young , Yu Eun Jeong , Kim Tae Soo , Shin You Keun , Kim Hyo Song , Chung Hyun Cheol , Roh Jae Kyung , Jeung Hei-Cheul
Published: June 2012

ADAM (A Disintegrin and Metalloproteinase)-9 is a cell-surface membrane glycoprotein, which enables diverse roles in a wide range of cellular process. Over-expression of ADAM-9 has been reported in several cancers but its biological role remained to be clarified in gastric cancer. Herein, we investigated the possible involvement of ADAM-9 related to invasion and metastasis in gastric cancer. We also evaluated its possibility as a therapeutic target for anti-metastasis treatment.

We examined transcription and expression pattern of ADAM-9 in 24 gastric cancer cell lines. ADAM-9 protease activity was measured using fluoregenic ADAM-9 substrate (R&D systems). We conducted trans-well assay coated with matrigel to associate ADAM-9 expression with invasion activity. A specific anti-ADAM-9 monoclonal antibody (RAV-18, Macrogenics, Inc.) was used to evaluate its anti-invasion property. And then, to evaluate the ADAM-9 protease activity in vivo, MKN-28, one of high ADAM-9 cell lines, was subcutaneously inoculated in flank of mice. The IP of mice were injected with or without RAV-18.

The protein expression and protease activity of ADAM-9 was various by each cell line. The protease activities were moderately correlated with the protein expressions (mature form) (R2 = 0.49). ADAM-9 protease activity was decreased dose-dependently on RAV-18 treatment, being remarkable in the cells of high ADAM-9 expression (SNU-638, YCC-1, MKN-74 and MKN-28) compared with low expressing cells (YCC-6, YCC-7 and HS-746T). Baseline level of invasiveness was poorly correlated with ADAM-9 expression, but in high ADAM-9 cells, the administration of RAV-18 significantly suppressed invasiveness, while not in low ADAM-9 cells. Exposure to hypoxia (1% O2, 5% CO2, 37°C) up-regulated protease activity and invasiveness in low ADAM-9 cells, and these were suppressed dose-dependently by the treatment of RAV-18. RAV-18 inhibited ERK phosphorylation in high ADAM-9 cells, which suggests that that ADAM-9-related invasiveness depends on its protease activity and it is, at least partially, via MAPK pathway. In vivo, the tumor volume of mice of RAV-18 treated group (n=7) was smaller than control group (n=7). As in vitro results, EGFR and Erk phosphorylation were reduced in RAV-18 treated group than control group.

This study shows that ADAM-9 is upregulated in gastric cancer, and that ADAM-9 might be a plausible target for therapeutic inhibition of invasion/metastatic process.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C43.
Abstract C6: Composite profiling of angiogenic factors using Bio-Plex Pro™ Human Cancer Biomarker Panel-I.
Authors: Zimmerman Richard B. , Hamilton Tim , Gupta Vinita , Ma Li
Published: June 2012

Angiogenesis is a feature of over 50 different disease states. These include cancer, rheumatoid arthritis, cardiovascular diseases, diabetes and psoriasis. Methods developed to study these diseases are important tool to establish a model for testing potential therapeutics. These methods include both in vivo and in vitro assays. In vivo angiogenesis assays are considered to be the most informative because of the complex nature of vascular responses to test reagents and responses that no in vitro model can achieve. However in vivo assays can be expensive, laborious and require extensive training to perform. In contrast, in vitro assays can be carried out expeditiously, less costly and easier to interpret. Often, these in vitro assays provide maximum benefit when developed as a multivariate index assay where the data of multiple assays function to yield a composite result to interpret experimental studies. Using the Luminex xMAP technology, we have developed a multiplex Bio-Plex Pro™ Human Cancer Biomarker Panel I that employs a magnetic bead-based workflow to measure angiogenesis biomarkers in diverse matrices including serum, plasma, cell culture supernatant and many other sample types. In combination with the Bio-Plex® suspension array and the Bio-Plex Pro™ wash station, the multiplexing feature makes it possible to quantify the level of multiple angiogenesis targets in a single well of a 96-well microplate in just 3 hours, using as little as 12.5 μL of serum or plasma. The panel of 16 markers includes sEGFR, FGF basic, Follistatin, G-CSF, sHER2/neu, HGF, sIL-6Ra, Osteopontin, Leptin, PDGF-BB, PECAM-1, Prolactin, SCF, sTie-2, sVEGFR-1 and sVEGFR-2. These markers were selected because of their direct relevance to the pathogenesis of tumor-associated angiogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C6.
Abstract C63: Targeting FGFR3 with monoclonal antibody impairs bladder cancer growth in vivo.
Authors: Du Xiangnan , Li Hao , Ingalla Ellen , Ross Sarajane , French Dorothy , Tien Janet , Ashkenazi Avi , Qing Jing
Published: June 2012

Fibroblast growth factor receptor 3 (FGFR3) belongs to a family of receptor tyrosine kinases that control cell proliferation, differentiation, and survival. Mutational activation of FGFR3 has been reported in about 50–60% low grade and 15–20% muscle-invasive bladder cancer. FGFR3 is also overexpressed in about 50% of muscle invasive bladder cancer, suggesting a potential role for this receptor in the early stage of bladder carcinogenesis. However, the expression pattern of FGFR3 and its functional importance in metastatic bladder cancer remain to be determined. Using immunohistochemistry, we have found that FGFR3 is overexpressed in 8/13 cases (about 62%) of lymph-node metastasis of bladder cancer. Extensive in vivo efficacy studies with an FGFR3-specific affinity-matured human monoclonal antibody (designated R3Mab) show that R3Mab as a single agent blocks FGFR3 signaling and suppresses the growth of multiple bladder tumor xenografts in mice. Importantly, R3Mab further enhances the anti-tumor activity of chemotherapeutics including gemcitabine and carboplatin. These results demonstrate that FGFR3 is required for the maintenance of bladder cancer of various stages, and support the clinical development of R3Mab in locally advanced and metastatic bladder cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C63.
Abstract C72: Counteracting autophagy allows to overcome resistance to the mTOR everolimus in mantle cell lymphoma.
Authors: Rosich Laia , Xargay-Torrent Silvia , Lopez-Guerra Monica , Campo Elias , Colomer Dolors , Roue Gael
Published: June 2012

Background: Mantle cell lymphoma (MCL) is an aggressive B-cell lymphoid neoplasm genetically characterized by the t(11;14)(q13;q32) leading to the overexpression of cyclin D1, which causes cell cycle deregulation at the G1-S phase transition. As a consequence of its poor response to conventional chemotherapy and relatively short patient survival, new therapeutic strategies are required.

The phosphatidylinositol 3-kinase/Akt/mTOR survival pathway is constitutively activated in MCL, thereby making the mTOR inhibition a very attractive strategy for its treatment. The first clinical studies conducted in relapsed MCL patients have reported a significant, but relative short duration of response to the oral rapamycin derivative everolimus (RAD001). In this context, our aim was to analyze the mechanism of action related to resistance/sentitivity of this drug in MCL cells, and to propose further combination strategies.

Methods: The sensitivity to everolimus was analyzed in MCL primary cultures, MCL cell lines and peripheral blood lymphocytes from healthy donors. Cells were treated for up to 72h with increasing doses of everolimus, followed by cytotoxicity quantification, cell-cycle determination and western blot analysis of the PI3K/Akt/mTOR pathway. Autophagy was studied by LC3I/II expression and Cell-ID™ Green staining of autophagolysosomes by flow cytometry and fluorescence microsopy.

Results: Everolimus exerted heterogeneous antitumoral effect on MCL cells, while sparing normal cells. This effect was associated with G1 cell-cycle arrest and reduced phosphorylation of the mTOR downstream targets, 4E-BP1 and S6. However, Akt re-phosphorylation was observed after 48h of everolimus treatment, suggesting feedbacks loops within the mTOR signaling pathway. Accordingly, everolimus combination studies with the Akt inhibitor VIII, isozyme-selective (Akti-1/2) showed synergistic cytotoxic effect in MCL cells and overcame Akt mechanism of resistance in a sub-set of MCL samples. When compared to these samples, increased levels of autophagic hallmarks such as autophagic vacuoles and LC3 processing were found in everolimus/Akti-1/2 low-responsive cells. In these cells, the combination with the autophagy inhibitor hydroxychloroquine overcame the resistance to mTOR/Akt inhibitors, and efficiently induced apoptosis, thus suggesting a prosurvival role of autophagy.

Conclusions: This study suggests that targeting autophagy as anticancer therapy may represent an attractive sensitizing strategy for everolimus-based therapy in MCL.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C72.
Abstract C82: Identification and preclinical characterization of inhibitors of the ubiquitin-activating enzymes UBA1 and UBA6.
Authors: Bence Neil , Fleming Paul , Ciavarri Jeff , Milhollen Michael , Pulukuri Sai , Hyer Marc , Traore Tary , Huck Jessica , Tou Derek , Sappal Darshan , Hoar Kara , Gavin James , Yang Yu , Brownell James , Smith Peter , Dick Lawrence , Veiby Petter , Manfredi Mark , Claiborne Christopher
Published: June 2012

Millennium Pharmaceuticals, Inc. is dedicated to the discovery and development of novel oncology therapeutics in the area of protein homeostasis. Here we report the identification and characterization of compounds that target the ubiquitin activating enzymes, UBA1 and UBA6. These compounds are mechanism based inhibitors that inactivate the ubiquitin E1 enzymes by forming a ubiquitin compound adduct that remains tightly associated with the E1 adenylate binding site. Treatment of cells with these inhibitors results in cellular effects consistent with known Uba1 biology including rapid loss of E2 ubiquitin thioesters, loss of total ubiquitin conjugates, and accumulation of many ubiquitin proteasome system substrates. Following prolonged treatment, cells primarily arrest in the G2 phase of the cell cycle and ultimately undergo apoptosis. Reflecting the extensive cellular roles of ubiquitin, the compounds also impact global protein turnover, ER stress and DNA damage repair. UBA1 inhibition impairs ubiquitination of PCNA and the Fanconia Anemia protein FANCD2 leading to defective repair of UV induced DNA damage. UBA1 inhibition impacts numerous biological pathways relevant to cancer, results in apoptosis in vitro and is capable of inhibiting tumor growth in mouse xenografts in vivo. These data implicate UBA1 as a target for the treatment of cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C82.
Abstract C9: Response to cetuximab is associated with EGFR gene amplification in gastric cancinoma patient derived xenograft models.
Authors: Yang Jie , Chen Dawei , Yang Mengmeng , Deng Jiangyun , Song Xiaoming , Cai Jie , Chen Taiping , Li Henry , Chen Yiyou
Published: June 2012

Gastric carcinoma is a common cancer in Asia with high mortality and few effective treatment options, with the exception of Herceptin in erbb2 over-expressing gastric cancer patients. Cetuximab has been approved for CRC and H&N, but not yet for gastric carcinoma. In this study, we set out to explore potential clinical utilities by testing cetuximab in a cohort of gastric cancer patient derived xenograft (PDX) models.

Among the 10 PDX models tested, all with wild type EGFR, 4 models (40%) were sensitive to cetuximab single agent treatment. Detailed gene expression and copy number variation analysis revealed that these 4 models have amplified EGFR gene, and correspondingly high EGFR mRNA expression level. In contrast, none of the 6 resistant models demonstrated EGFR amplification. The strong association suggests that EGFR gene amplification is a major driver for the maintenance of gastric cancer. In summary, by modeling clinical trial, our studies using large panel PDXs has identified a promising predictive biomarker for cetuximab responsiveness in gastric carcinoma patients. Further clinical investigation on patients with EGFR gene amplification is warranted.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C9.
Abstract C95: A flexible kinase inhibitor assay platform for active, nonactivated, and impure kinase preparations.
Authors: Lebakken Connie S. , Reichling Laurie , Ellefson Jason , Bi Kun , Riddle Steven M.
Published: June 2012

Kinase activity-based assays are cost-effective and widely used to drive early drug discovery and lead identification, however, they typically require purified, active kinase preparations be produced that are shown to phosphorylate a known substrate. While it is possible to satisfy these requirements for the well-studied kinases, there are many kinases which lack one or more of these requirements, such as CDK8 and STK33, making drug discovery efforts difficult. To solve for these assay development problems, we have developed a TR-FRET-based binding assay platform which allows for characterization of compounds with kinases that are not sufficiently purified or do not demonstrate measurable activity against putative or potential substrates. This assay addresses kinase assay requirements early in the drug discovery process, and should enable more targets to be screened sooner, resulting in compounds being made available for lead optimization faster. The ability to detect and characterize binding of compounds to non-activated kinases is also a benefit to the lead optimization process, as compounds that bind preferentially to kinases in their non-activated state, such as Imatinib, are sometimes preferred due to their selectivity. In this poster, we present solutions for kinases that are difficult to address with activity assays and provide a comparison of compound affinities for active and non-activated forms of a diverse set of kinases to enable faster lead optimization.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C95.
Abstract PR-12: Loss of the retinoblastoma protein alters glucose and glutamine metabolism.
Authors: Clem Brian F.
Published: June 2012

Tumorigenesis requires not only loss of proliferative control, but also a metabolic shift towards increased glucose and glutamine consumption required for increased energy production and to drive the de novo biosynthesis of nucleotides, amino acids, and lipids essential for cell division. These processes are primarily driven through oncogenes or loss of tumor suppressors, which act to circumvent normal regulatory pathways. The retinoblastoma (Rb) protein, the first described tumor suppressor, is extensively involved in cell cycle regulation, and perturbations within the Rb pathway are found in most tumor types. Beyond cell cycle control, Rb has been implicated in multiple additional biochemical pathways known to be involved in tumor progression, such as metastasis and angiogenesis. However, little is known about the role of Rb in regulating the unique changes in metabolism that have been observed in human cancers. Using stable 13C-glucose isotopomer NMR analysis, we found that triple knock-out (TKO) of all three Rb family members in mouse embryonic fibroblasts (MEFs) resulted in increased glucose uptake and flux to lactate, and simultaneously decreased glucose-derived carbon incorporation into Krebs' cycle intermediates relative to wild-type (WT) MEFs. To supplement this loss of glucose carbons for anaplerosis within the Krebs' cycle, we speculated that the Rb TKO MEFs may increase glutamine uptake for both bioenergetic and anabolic precursors. We observed that loss of Rb caused increased 13C-glutamine uptake and flux into glutamate and Krebs' cycle intermediates using isotopomer NMR analyses. Importantly, this shift towards glutamine utilization was essential for the survival of Rb TKO MEFs and not for the WT MEFs. Preliminary studies of the precise downstream metabolic enzymes that may in part mediate these global changes in metabolism then demonstrated that the expression of distinct regulatory metabolic enzymes, including glucose transporters, hexokinase 2, and glutaminase 1, are simultaneously increased in the Rb TKO MEFs compared to WT MEFs. Combined, these studies suggest that inactivation of the Rb protein in human cancers leads to a global metabolic shift towards enhanced glycolysis and glutamine utilization, which in turn is required for neoplastic immortalization and transformation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr PR-12.
Abstract 100: The effect of synergic anti-proliferation of DNA methyltransferase inhibitor binding to anti-cancer drugs in gastric cancer
Authors: Muguruma Kazuya , Yashiro Masakazu , Tanaka Hiroaki , Kimura Kenjirou , Nagahara Hisashi , Amano Ryousuke , Noda Eiji , Kubo Naoshi , Yamada Nobuya , Maeda Kiyoshi , Ohira Masaichi , Ishikawa Tetsurou , Hirakawa Kosei
Published: June 2012

Epigenetic alterations of DNA methylation play an important role in the regulation of gene expression associated with chemosensitivity of gastric carcinomas. With the aim of improving the chemotherapeutic efficacy of gastric carcinoma, the effect of DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine, on the chemosensitivity of five anti-cancer drugs was investigated. Human gastric cancer cell lines, OCUM-2M and MKN-74, and five anti-cancer drugs, 5-fluorouracil, paclitaxel, oxaliplatin, irinotecan, and gemcitabine, were used. In both gastric cancer cell lines, a synergistic anti-proliferative effect by a combination of 5-aza-2′-deoxycytidine at 5μ M was found in irinotecan or gemcitabine. 5-Aza-2′-deoxycytidine at 5μM increased apoptosis induced by irinotecan and gemcitabine in both cell lines. 5-Aza-2′-deoxycytidine increases the expression of DAPK-2 and DAPK-3, RASSF1, and THBS1 gene in both OCUM-2M and MKN-74 cells, but not that of hMLH1, p16, MGMT, E-cadherin, and p53 genes. These findings suggest that 5-aza-2′-deoxycytidine is a promising chemotherapeutical agent for gastric carcinomas in combination with anti-cancer drugs of irinotecan and gemcitabine in apoptosis signaling. The up-regulation of DAPK-2 and DAPK-3, RASSF1, and THBS1 genes by 5-aza-2′-deoxycytidine might be associated with the synergistic effect.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 100. doi:10.1158/1538-7445.AM2011-100