bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5434: Functional screening for impact on cancer hallmarks migration, transformation and angiogenesis identifies potential new drug leads isolated from marine organisms
Authors: Ehlert Jan E. , Weber Holger , Mueller Melanie , Siedentopf Oliver , Lin Wenhan , Proksch Peter , Kubbutat Michael HG
Published: June 2012

Marine organisms represent a potential new source for lead compounds applicable for cancer therapy. Traditionally, natural sources have been in the focus of drug discovery and have so far yielded an impressive number of drugs that are indispensable in modern therapy. About two thirds of all anti-cancer drugs approved today are in fact either natural products or have been developed on the basis of knowledge gained from natural products. This is especially pronounced in the field of cancer chemotherapy. Of special interest to us were compounds from so far under-explored and under-exploited marine organisms from China and Vietnam. In this study compounds from such organisms have been isolated and analysed in phenotypic cellular assays for their inhibitory impact on critical hallmarks of cancer. For that purpose, we have developed medium throughput phenotypic assays to look at transformation, angiogenesis and migration, indicated by soft agar growth, endothelial sprouting and wound healing, respectively. We report on a phenotypic screen of 160 compounds derived from marine organisms, which lead to the identification of several differentially inhibitory substances which are subsequently analysed in detail.

This project was funded by the German ministry of Science and Education; Grant No 0315322.

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 5434. doi:10.1158/1538-7445.AM2011-5434
Abstract 5437: Novel drug sensitivity test using three-dimensional primary lung cancer cell culture on microfabricated surface
Authors: Shimomura Manami , Sakamoto Ruriko , Yoshida Kaori , Ueda Ikuyo , Yonemura Masahito , Shimada Yoshihisa , Nakatsura Tetsuya
Published: June 2012

Purpose: The behavior of cells cultured within three-dimensional structures more closely reflects their in vivo responses than onto two-dimensional culture. We established novel 3D primary cell culture on microfabricated surface and studied whether it was useful for drug sensitivity test in lung cancer. Experimental design: The cancerous portions of the lung cancer specimens were disrupted into single cell suspension and the 5 × 104 cells per well were seeded on novel nanotechnology-based 3D culture plate (Nanoculture plate®: NCP, SCIVAX Corp.), which has approximately 2-3μm diameter of micro fabrications on the culture surface. When the cancer cells formed the multicellular spheroids, anticancer drugs (GEM and Gefitinib; each concentration was 1uM and 10uM) were added and measured ATP quantity of living cells after 72 h. Fluorescence immunostaining of cytokeratin-18, the marker of lung epithelial cells, and α-SMA, the marker of fibroblast, were performed to examine the constituent cells. Results: Lung cancer cells rapidly formed multicellular spheroids on the NCP. It was revealed that these multicellular spheroids consisted of cancer cells and fibroblasts by staining α-SMA and cytokeratin-18. In one case showed sensitivity against Gefitinib but not against GEM, there was exon 19 deletion of EGFR in the cancer specimen. Discussion and Conclusion: This culture system could be useful for further evaluation such as individual chemotherapy sensitivity assays and for finding novel molecular targets for cancer drug.

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 5437. doi:10.1158/1538-7445.AM2011-5437
Abstract 544: Blockade of CXC chemokines/CXCR2 axis in the tumor microenvironment as a potent therapeutic strategy for pancreatic ductal adenocarcinoma
Authors: Ijichi Hideaki , Tada Motohisa , Miyabayashi Koji , Mohri Dai , Asaoka Yoshinari , Tateishi Keisuke , Ikenoue Tsuneo , Omata Masao , Koike Kazuhiko , Moses Harold L.
Published: June 2012

Pancreatic ductal adenocarcinoma (PDAC), one of the most lethal neoplasms, is characterized histologically by expanded stromal components with marked fibrosis, which suggests that tumor-stromal interaction might play an important role in PDAC progression.

We have established pancreas epithelium-specific transforming growth factor-ß receptor type II (Tgfbr2) knockout mice in the context of active Kras (KrasG12D) expression (Kras+Tgfbr2KO), which developed differentiated PDAC with 100% penetrance and recapitulated histology of human PDAC described above.

In the AACR annual meetings 2009-10, we have reported that tumor-stromal interaction in the PDAC model promoted tumor progression and blockade of CXC chemokines/CXCR2 axis inhibited tumor growth and extended survival of the mice.

We further examined the underlying mechanisms of tumor-stromal interaction. The CXC chemokines secreted from the PDAC cells did not change autocrine PDAC cell proliferation nor that of stromal fibroblasts, but induced CTGF expression in the stromal fibroblasts and promoted tumor angiogenesis, which resulted in promotion of tumor growth. Expression of the CXC chemokines was downregulated by TGF-β signaling, whereas, NF-κB signaling was required for the expression. Subcutaneous xenografts coinjected with the PDAC cells and fibroblasts grew faster than those with PDAC cells alone, which suggested tumor-promoting tumor-stromal interaction. We further examined the xenograft growth of CXCR2-knocked down (KD) PDAC cells and CXCR2-intact firbroblasts, compared with that of CXCR2-intact PDAC cells and CXCR2-KD fibroblasts. Results suggested that intact CXCR2 in the stromal fibroblasts was required for the tumor-promoting CXC chemokines/CXCR2 axis. In conclusion, blockade of the CXC chemokines/CXCR2 axis might have a key role in modulating the tumor microenvironment and for development of more effective therapeutic strategy for PDAC.

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 544. doi:10.1158/1538-7445.AM2011-544
Abstract 5457: Contexts of vulnerability mediating TMZ response in metastatic melanoma
Authors: Yin Holly , Brooks Bradford , Chow Donald , Sereduk Chris , Sekulic Aleksandar , Brown Kevin , Trent Jeff
Published: June 2012

Metastatic malignant melanoma is an incurable disease with average 5-year survival rates for patients with disseminated disease ranging from 5-18%. Despite the recent development of promising targeted and immunological approaches for treatment of melanoma patients, there remains an urgent need to improve the effectiveness of conventional chemotherapeutics such as TMZ treatment for those patients ineligible or unresponsive to these approaches. We hypothesized that genetic alterations or contexts of vulnerability (COVs) exist in melanoma cells that mediate sensitivity to TMZ, and thus developed RNA-interference-based (RNAi) TMZ chemosensitization assays in melanoma cell lines in order to better understand how to pharmacologically augment TMZ response. First, we extensively developed RNAi sensitization assay in 17 melanoma cell lines followed by screening siRNA kinome library in these cell lines. This screening result, combined with our previous melanoma genomic data (gene expression, aCGH, SNP, and gene mutations), would prioritize the critical essential genes in melanoma. In addition, we profiled 17 melanoma cell lines for TMZ sensitivity and subsequently optimized RNAi screening parameters for detection of TMZ sensitization in one sensitive (UACC903) and four resistant (UACC647, UACC1308, UACC91 and UACC1940) cell lines. We then performed high-throughput RNAi screens with a 7,000 gene siRNA library targeting the druggable genome in these five cell lines. The data from the screens were rigorously evaluated and top TMZ-sensitizing hits were identified and confirmed. Based on these data, we prioritized the ATR/ATM/Chk1 pathway for further evaluation. We tested two Chk1 inhibitors for synergistic effects when combined with TMZ. Notably, both Chk1 inhibitors demonstrated good synergistic effects in the TMZ-resistant cell lines, with moderate/marginal effects in the sensitive line UACC903. These data are consistent with previous reports that inhibition of Chk1 can sensitize TMZ-induced cytotoxicity in glioma cells, and suggest that targeting this pathway in melanoma may augment TMZ response in melanoma. We are presently following up these results across a larger panel of melanoma cell lines, as well as evaluating pharmacological inhibitors of additional TMZ-sensitizing siRNA hits and pathways with the hope that these results may serve as a starting point for the development of novel combination therapies for melanoma patients.

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 5457. doi:10.1158/1538-7445.AM2011-5457
Abstract 5464: Determination of total and encapsulated drug pharmacokinetics for CPX-351, a nanoscale liposomal fixed molar ratio of cytarabine-daunorubicin (Cyt:Daun)
Authors: Ciofani Travis , Harasym Troy , Juan Michael C.Y. , Mayer Lawrence , Cabral-Lilly Donna , Xie Sherwin
Published: June 2012

Background: CPX-351 is a liposomal formulation that delivers elevated concentrations of Cyt and Daun after administration in vivo and maintains the two drugs at a 5:1 molar ratio shown to be synergistic in preclinical studies. Pharmacokinetic analysis of CPX-351 in advanced leukemia patients demonstrated prolonged plasma exposure of the drugs with quantifiable concentrations of both agents being observed as long as 7 days after the final CPX-351 dose. Here we developed a method to separate liposome-bound from unencapsulated drugs, thereby allowing the pharmacokinetics of encapsulated agents to be determined in comparison to total plasma drug concentrations.

Methods: CPX-351 was administered to female Sprague-Dawley rats via IV bolus injection. Plasma samples were harvested at five timepoints from 1 – 24 hours. Unencapsulated drug analysis was conducted by addition of internal standards (gemcitabine (Cyt) and doxorubicin (Daun)) to the plasma, followed by a 5-fold dilution in buffer and ultrafiltration using Microcon YM-30. Unencapsulated drug levels were determined by reversed-phase HPLC-MS (SIM, 244.2 m/z (Cyt) and 528.3 m/z (Daun)). Total analysis was conducted by protein precipitation and analysis was determined by reversed-phase HPLC-UV (Cyt) and reversed-phase HPLC-Fluorescence (Daun).

Results: A separation method was developed to separate 0.22 – 4.33% unencapsulated Cyt and 0.13 – 2.50% unencapsulated Daun from liposome in plasma matrix. Encapsulated drug was calculated by subtracting the amount of unencapsulated analyte from the corresponding amount of total analyte. The total drug curves and the calculated encapsulated drug curves from 1 – 24 hours were superimposable for Cyt and Daun. A maximum of 1.9% unencapsulated Cyt and 0.4% unencapsulated Daun was measured in the plasma at any time point.

Conclusions: Unencapsulated drug levels in rat plasma are insignificant compared to the total drug levels such that levels of total and encapsulated are within the spread of the data and therefore indistinguishable. These results suggest that CPX-351 remains in circulation in rats as intact liposomes at least 24 hours post administration.

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 5464. doi:10.1158/1538-7445.AM2011-5464
Abstract 5470: Potent MEK inhibitor CIP-137401: Preclinical studies
Authors: Khire Uday R. , Bhargava Ajay , Hart Barry , Chordia Mahendra D.
Published: June 2012

In recent years there is a lot of interest in both pre-clinical and clinical setting for the development of MEK kinase inhibitors as therapeutic agents for various cancers. A quite few number of MEK kianse inhibitors are currently undergoing phase I/II clinical trials both as a single agent as well as a combination with variety of other anti-tumor agents. These single agents include AZD-6244, RDEA-119, GSK-1120212, AS-703026 etc. One of the factors favoring MEK kinase as a sought after target besides being a part of very relevant Ras-Raf-MEK-ERK pathway is the identification of an allosteric binding site, which provides excellent selectivity for MEK kinase inhibitors as a class. Constitutive activation of Ras-Raf-MEK-ERK pathway has been a hallmark in several cancer types, including pancreatic, colon, lung, and melanoma. MEK is selective in phosphorylating serine/threonine residues of proteins resulting in regulation of variety of physiological functions of the cell including apoptosis, differentiation, proliferation and gene expression.

We recently discovered a novel, potent, non-ATP competitive, allosteric class of MEK kinase inhibitors. Our lead compound, CIP-1374, in the preliminary in vitro data that include primary enzyme assay, inhibition of ERK phophorylation, and anti-proliferation assays in various cell lines exhibited very potent activity. CIP-1374 also displayed excellent pharmaco-kinetic profile in mice with about 17h of half life with about 30% oral bioavailability. Another molecule in this series, CIP-137401 is also displaying a potent in vitro activity in various assays. We are currently focusing on CIP-137401 as our lead candidate and conducting preclinical studies. In this poster, our results in preclinical studies including rat pharmaco-kinetic, metabolic stability, and in-vitro toxicology data will be presented. The in vitro toxicology assays include its profiling in cardiac toxicity data (hERG channel activation). In addition the efficacy data from in vivo tumor xenograft models will be presented.

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 5470. doi:10.1158/1538-7445.AM2011-5470
Abstract 5471: Pharmacokinetic investigation of vandetanib in patients with medullary thyroid carcinoma using liquid chromatography-tandem mass spectrometry
Authors: Broutin Sophie , Deroussent Alain , Paci Angelo , Ryan Anderson Joseph , Schlumberger Martin , Bidart Jean-Michel
Published: June 2012

Introduction: Vandetanib is a once-daily oral multikinase inhibitor with antitumoral activity in patients with advanced medullary thyroid carcinoma (MTC). The aim of this study was to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of serum vandetanib levels and to investigate the pharmacokinetic/pharmacodynamic relationship in MTC patients.

Materials and Methods: A LC-MS/MS method was developed using acetonitrile/water 0.1% acetic acid (80:20, v/v). Serum proteins were precipitated with cold acetonitrile after addition of trazodone used as internal standard (IS). Vandetanib was detected and quantitated by multiple reactions monitoring of the ion transitions m/z 475–>112 (vandetanib) and m/z 372–>176 (IS). Serum from 28 MTC patients (clinical study D4200C00058) was collected during each course of vandetanib treatment (initial dosing 300 mg/day) from 1 week to 36 months and stored at -20°C before analysis. Exposure monitoring was investigated retrospectively on 121 samples.

Results: Mean extraction recoveries from human serum were 103±3% and 94±2 % for vandetanib and IS, respectively. The calibration curve was linear for a range spanning 2.5-5,000 ng/mL. The accuracy was 92% at the lower limit of quantitation of 2.5 ng/mL with good precision (CV <10%). Intra-day and inter-day quality control accuracies ranged from 90 to 97% (CV <5%) and from 90 to 99% (CV< 6%). Median vandetanib serum levels evaluated in MTC patients indicated a progressive rise from ∼400 ng/ml (at 1 week) to ∼800 ng/ml (at 3 months) that persisted over time. Half of patients (n=14) presented serious toxicity that required treatment interruption and/or dose reduction. Interestingly, most patients with serious toxicity (n=11/14) had a maximal vandetanib level greater than 20% above the median level versus only one patient in the non-serious toxicity group (n=14).

Conclusion: We developed and validated a fast and sensitive LC-MS/MS method allowing the quantitation of vandetanib levels in human serum. Results indicated that MTC patients display different vandetanib pharmacokinetic profiles. The relationships between these profiles and toxic side-effects and/or efficacy deserve further investigations.

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 5471. doi:10.1158/1538-7445.AM2011-5471
Abstract 5482: c-Met and DR5 co-expression is an independent prognostic marker for better survival in colorectal carcinoma
Authors: Uddin Shahab , Hussain Azhar R. , Ahmed Maqbool , Al-Sanea Nasser , AbdulJabbar Alaa , Ashari Luai H. , Al-Homoud Samar , Al-Dayel Fouad , Bavi Prashant , Al-Kuraya Khawla S.
Published: June 2012

Recently, dysregulated over-expression of hepatocyte growth factor (HGF) and its receptor, c-Met has been reported in variety of cancers. However, its role in colo-rectal carcinoma (CRC) has not been fully elucidated. Therefore, we investigated the role of c-Met in a large series of Middle Eastern CRC patient samples and CRC cell lines. c-Met was over-expressed in 86.8% of CRC and was strongly associated with expression of p-AKT (p<0.0001), DR5 (p=0.0084) and Ki67 (p=0.011) by immuno-histochemistry. Co-expression of c-Met and DR5 was associated with less aggressive phenotype, a better overall survival (p=0.0027) and was an independent prognostic marker. In vitro, PHA665752, a selective c-Met inhibitor, inhibited growth and induced apoptosis in CRC cells. Additionally, PHA665752 treatment caused dephosphorylation of c-Met, AKT and its downstream effector targets FOXO1, GSK-3 and p-Bad. Interestingly, PHA665752 treatment of CRC cell lines also caused up-regulation of DR5 and combination treatment with TRAIL and PHA665752 significantly synergized CRC cells to undergo apoptosis. In-vivo, co-treatment of CRC xenograft with PHA665752 and TRAIL significantly reduced tumor volume and weight. Protein analysis of in-vivo xenografts by immuno-blotting showed that co-treatment with TRAIL and PHA665752 inactivated met and AKT more effectively as compared to treatment with TRAIL or PHA665752 alone. Finally, activation and cleavage of caspase-3 was more pronounced in CRC xenografts treated with combination of TRAIL and PHA665752. Altogether, these data demonstrate a significant correlation between expression of c-Met and DR5 in CRC patients. Furthermore, inhibition of c-Met signaling by PHA665752 in combination with TRAIL significantly inhibited cell growth and induced apoptosis in CRC cell lines suggesting that this may have significant clinical implications as a therapeutic target in the treatment of CRC.

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 5482. doi:10.1158/1538-7445.AM2011-5482
Abstract 5499: Temozolomide (TMZ) cytotoxicity in human melanoma cell lines is enhanced by concomitant treatment with the histone deacetylase (HDAC) inhibitor vorinostat (SAHA) and PARP inhibitor MK-4827
Authors: Tawbi Hussein , Kirkwood John M. , Lin Ying-Chih , Buch Shama C. , Lin Yan , Kublo Lyubov , Beumer Jan H. , Egorin Merrill J. , Chu Edward , Hershberger Pamela
Published: June 2012

Introduction: TMZ is a non-classical alkylating agent that induces DNA damage leading to cytotoxicity, with modest clinical activity in metastatic melanoma. DNA repair modulation with PARP inhibitors enhances TMZ cytotoxicity in vitro and in vivo, and this strategy is being investigated in clinical trials. We hypothesized that HDAC inhibition with SAHA would lead to increased DNA damage and potentiate the effect of the PARP inhibitor MK-4827 on TMZ cytotoxicity.

Methods: Human melanoma cell lines A375 and FEMX-1 were used. Cells were treated in the absence or presence of TMZ, SAHA, and MK-4827 at the indicated concentrations for 72 hr in 96-well plates. Cell viability was determined using MTS assays and normalized to vehicle-treated control cells. Drugs were used at the final concentrations indicated in Table 1.

Results: MK-4827 at 10 nM increased the cytotoxicity of TMZ in FEMX-1 but not in A375 cells, however 100 and 200 nM MK-4827 moderately potentiated TMZ cytotoxicity in both cell lines. The combination of TMZ with 1 µM SAHA and 200 nM MK-4827 resulted in profound cytotoxicity at reduced doses of TMZ (0.2 mM in FEMX-1 and 1.0 mM in A375), much lower than TMZ alone or in combination with either SAHA or MK-4827. >80% cell kill was achieved in A375 and >95% in FEMX-1 near the IC50 concentration of TMZ and at clinically achievable concentrations.

Conclusion: PARP inhibition offers a strategy to reverse melanoma TMZ resistance. The concomitant inhibition of HDAC with SAHA and of PARP with MK-4827 profoundly enhanced TMZ cytotoxicity at clinically achievable doses of all 3 agents. We are presently optimizing the dosing schedules of the 3 drugs in preclinical models and investigating the mechanism(s) underlying this potentiation. These findings support the investigation of the triple drug combination (TMZ+SAHA+MK-4827) for metastatic melanoma.

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 5499. doi:10.1158/1538-7445.AM2011-5499
Abstract 55: Prediction of miRNA target genes using a hidden Markov model
Authors: Lee Chien-Yueh , Hung Jui-Hui , Tsai Mong-Hsun , Hsiao Chuhsing Kate , Chuang Eric Y. , Lai Liang-Chuan
Published: June 2012

MicroRNAs (miRNAs) are short non-coding RNAs about 22 nucleotides in length that play important regulatory roles in animals for translational repression by targeting mRNAs. Recent studies reported that miRNAs may function as tumor suppressors or oncogenes, and the alterations in miRNA expression may be critical in tumor genesis and cancer progression. Using computational methodologies can rapidly identify miRNA targets in massive data, and provide rich gene-related information for human cancer studies. However, it is challenging to predict targets in animals due to imperfect complementarity between miRNAs and mRNA targets. In order to further improve the prediction performance, we proposed a novel miRNA target-gene prediction algorithm that combines several conventional prediction models including the sequence complementary searching for calculating alignment scores and thermodynamic stability approaches for assigning folding free energy to each miRNA-target interaction.

A Hidden Markov Model (HMM), a well known machine learning approach, was implemented in the algorithm to help the prediction decision. However, an HMM cannot consider all global information of the sequences due to its innate limitation. Therefore, forward and backward HMMs were simultaneously utilized in the proposed algorithm to overcome this limitation. As a result, any element information of miRNA-target interactions was able to pass to any other element by bi-directions. The proposed algorithm can predict the cancer-related miRNA target genes through a suitable combination of the proposed models. The results show that the highest sensitivity, specificity, and overall accuracy were 84.25%, 96.78%, and 96.67%, respectively. Based on our analysis, 52.42% prediction result of the proposed algorithm was consistent with other existing prediction algorithms. Furthermore, the predicted target genes obtained by the proposed algorithm could be likely found from the potential cancer-related genes discovered by microarray data. A total of 70.37% predicted target genes were significantly overlapped with the cancer-related genes from microarray data, suggesting these genes were substantially regulated by miRNAs in cancer. In conclusion, our proposed novel algorithm is able to predict miRNA target genes, commonly found among microarray-identified dysregulated genes in previous cancer studies.

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 55. doi:10.1158/1538-7445.AM2011-55
Abstract 5508: B lymphocytes are activated during the course of sipuleucel-T treatment, leading to an antigen-specific humoral response
Authors: Wesley Johnna , Kuan Ling-Yu , Chadwick Eric , Perdue Nikole , dela Rosa Corazon , Frohlich Mark , Urdal David , Sheikh Nadeem
Published: June 2012

Introduction: Sipuleucel-T is an autologous cellular immunotherapy FDA approved for men with asymptomatic or minimally symptomatic metastatic castrate resistant prostate cancer (mCRPC). Previous clinical data have shown that antibodies specific for the immunizing antigen, PA2024, develop within two weeks post-end of sipuleucel-T treatment. Here, we sought to determine whether B lymphocytes were activated during the course of treatment and to evaluate their phenotypic profile in two ongoing clinical studies (NEoACT and PRoACT).

Materials and Methods: Sipuleucel-T is manufactured from peripheral blood mononuclear cells (PBMCs) isolated every two weeks by leukapheresis. The PBMCs are cultured with PA2024, an antigen composed of prostatic acid phosphatase (PAP) fused to granulocyte macrophage-colony stimulating factor (GM-CSF), washed, and then infused into the patient as sipuleucel-T. Each patient receives three infusions. The activation status of B lymphocytes was evaluated by multi-color flow cytometry during the manufacture of sipuleucel-T, before and after culture at each of the three treatment times. B lymphocyte subsets were identified by their expression of CD20, IgD and CD27: CD20+IgD+CD27− naive, CD20+IgD+CD27+ mature activated, and CD20+IgD−CD27+ memory. Activation of each of these subsets was determined by their expression of CD80 and CD96. Antigen-specific B lymphocyte function, in the form of antibody production, was evaluated in the serum of sipuleucel-T-treated subjects before and after treatment.

Summary: In the mature activated B lymphocyte subset, an increase in the proportion of lymphocytes expressing CD80+ and CD86+ was detected following culture with PA2024, with the increase in CD86+ mature B lymphocytes being the highest after the second infusion of sipuleucel-T. An increase in mature activated B lymphocytes directly ex vivo, pre-culture, was not observed prior to the second or third infusion. Additionally, CD80 and CD86 expression was upregulated on memory B lymphocytes in response to culture with PA2024 and following the first infusion. Furthermore, PA2024- and PAP-specific antibody responses were detected and maintained 2-22 weeks after the completion of sipuleucel-T treatment.Conclusions: These data demonstrate that B lymphocyte activation is a consequence of ex vivo culture with PA2024 and precedes an antigen-specific humoral response, as detected in the patients’ serum after treatment with sipuleucel-T. Collectively, these findings provide evidence of therapy-induced humoral immune activation in men with mCRPC treated with sipuleucel-T.

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 5508. doi:10.1158/1538-7445.AM2011-5508
Abstract 551: A potent and selective cFMS inhibitor regulates the tumor macrophage microenvironment leading to tumor growth inhibition
Authors: Wright Albion D. , Willis Brandon S. , Gomez Anna , Boys Mark L. , DeLisle Robert K. , Burgess Laurence E. , Munson Mark C. , Kennedy April L. , Topalov George T. , Zhao Qian , Rodriguez Martha E. , Rast Bryson , Rizzi James P. , DeWolf Walter E. , Lemieux Christine , Anderson Deborah , Neale Jason R. , Martinson Matthew , Gross Stefan D. , Callejo Michele , Risom Tyler , Lee Patrice A.
Published: June 2012

Increasing evidence suggests that interactions between tumor cells, stromal cells, macrophages and the extracellular matrix are pivotal to the processes of tumorigenesis, metastasis, and neovascularization. Macrophages within the tumor microenvironment are thought to facilitate cancer progression, making them intriguing targets for therapy. Colony stimulating factor 1 (CSF-1) and its receptor, cFMS, play a central role in the development of mononuclear phagocytes, recruitment of macrophages to tumors, and differentiation and function of osteoclasts. We have developed an orally active, selective small-molecule cFMS inhibitor for cFMS. This molecule inhibits cFMS cellular activity (IC50 = 9 nM) in vitro and inhibits cFMS phosphorylation in a transfected cell line grown in nude mice (ED50 = 3 mg/kg). Our compound also inhibits CSF-1-mediated osteoclast differentiation and function (IC50 values of = 4 nM and 58 nM, respectively). To further explore the potential of our selective inhibitor for the treatment of cancer, we evaluated anti-tumor activity in several preclinical models. We first explored the effect on the murine ovarian cancer cell line, ID8. ID8 cells injected intraperitoneally into nude mice form multiple peritoneal tumor deposits and abundant ascites. Macrophage infiltration in the ID8 ascites was markedly lowered in mice treated with a cFMS inhibitor. Using MCF-7, a human breast adenocarcinoma cell line that has been shown to produce M-CSF, a daily oral dose with 100 mg/kg of our inhibitor for 21 days significantly reduced tumor growth and was accompanied by a marked reduction in tumor-associated macrophages. These findings support the potential of a selective inhibitor of cFMS to favorably impact human cancers by modulating tumor-associated macrophage functions.

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 551. doi:10.1158/1538-7445.AM2011-551
Abstract 5510: Immunogenicity of the MUC1/Poly-ICLC vaccine in individuals with the history of advanced colorectal adenoma
Authors: Kimura Takashi , McKolanis John R. , Schoen Robert E. , Finn Olivera J.
Published: June 2012

Background: MUC1 is aberrantly expressed in human adenocarcinomas including colon cancer. Aberrant MUC1 is also found on colorectal adenomas where it promotes malignant transformation by interacting with beta-catenin, ras and other signaling pathways. Induction of immunity against MUC1 during premalignancy may prevent adenoma recurrence and/or their progression to colon cancer. Various MUC1 vaccines, peptide and adjuvant-based, dendritic cell-based or as various viral vectors, have been tested previously in small Phase I/II trials in patients with advanced cancer and have shown low immunogenicity and limited efficacy. In the cancer microenvironment, it is difficult to determine if low immunogenicity is due to the vaccine, to self-tolerance, to the immunosuppressive tumor microenvironement, previous treatments, age of the patient or all of the above. We are conducting a trial using MUC1 peptide and Poly-ICLC adjuvant vaccine in individuals who are cancer free but at high risk for developing cancer because of a recent history of advanced colorectal adenoma.

Method: Patients with advanced colorectal adenoma which meets at least one of following criteria, 1) ≥ 1cm in maximal diameter, 2) with villous or tubulovillous histology, 3) with high-grade dysplasia, were vaccinated with 100μg of 100aa MUC1 peptide [H2N-(GVTSAPDTRPAPGSTAPPAH)5-CONH2] admixed with 500μg of Poly-ICLC (TLR-3 agonist) as adjuvant on week 0, 2, 10 and one year later. The primary objective is to evaluate the vaccine immunogenicity (anti-MUC1 IgG and T cell responses) and safety.

Results: 43/65 patients have been enrolled. Among 31 patients studied to date, 16 developed anti-MUC1 IgG (52% response rate). This frequency of responders and the high levels of IgG (3-30 fold increase) have never been achieved in cancer patients. Antibody titers declined over time but could be boosted to previous or higher levels at 1 year, showing development of long-term memory. Confirmatory T cell assays are in progress. No adverse events above grade 1 have been identified, and no unanticipated adverse events have been observed.

Conclusions: MUC1 poly-ICLC vaccine is highly immunogenic in this prophylactic setting without causing any significant adverse events. Recurrence of adenomas will be evaluated at year 3 and correlated with the immune response, however, a larger randomized trial will be needed to properly evaluate the clinical outcome.

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 5510. doi:10.1158/1538-7445.AM2011-5510
Abstract 5518: Characterization of invariant natural killer T cells in patients with advanced melanoma treated with CTLA4 blockade and dendritic cell vaccination
Authors: Ibarrondo Javier -. , Comin-Anduix Begoña -. , Lee Yohan -. , Chodon Thinle -. , Sazegar Hooman -. , Jalil Jason -. , Chmielowski Bartosz -. , Koya Richard C. , Gomez-Navarro Jesus -. , Jamieson Beth D. , Ribas Antoni -.
Published: June 2012

Background. Invariant CD1d-restricted T cells (iNKT) are a T lymphocyte subset with a key role in the innate and adaptive immune systems and have been implicated in protection against cancer. iNKT cells are activated by lipid antigen presentation by CD1d on myeloid dendritic cells (mDC). Upon activation, iNKT produce Th1 and Th2 cytokines. CD4+ iNKT cells have a Th2 profile, while CD4- and CD4-CD8- (DN) subsets, behave as Th1 T-cells. We studied the phenotype of iNKT in patients treated with the anti-CTLA4 monoclonal antibody tremelimumab alone or combined with MART-126-35 peptide-pulsed dendritic cells (MART-1/DC) to explore possible associations between iNKT with treatment outcomes.

Methods: Peripheral blood mononuclear cells (PBMC) were obtained before and after treatment with tremelimumab alone (n=21) or tremelimumab with MART-1/DC (n=8). There were 4 patients with an objective response in the combined therapy group and 3 patients with an objective response in the tremelimumab alone group. The number and phenotype of T cell and iNKT were characterized by multi-color flow cytometry.

Results. Approximately one month after the first dose of combined treatment the percentage of iNKT-cells increased over baseline, while the percentage of iNKT cells decreased in patients treated with tremelimumab alone. In patients receiving combined treatment, those with a clinical response had a significantly higher iNKT number than non-responders. Overall, iNKT phenotypes did not change in either treatment group during treatment. However, clinical responders receiving combined therapy exhibited a high percentage of iNKT-CD8+ cells and low percentages of iNKT-CD4+. In contrast, in the non-responders and patients treated with tremelimumab alone, the iNKT CD8 to CD4 subset ratio was inverted. The combined iNKT subsets (CD4+, DN+, and CD8+) shared a common phenotype of CCR5+, CD62L+ and CD45RA+ and the phenotype did not change over time. For the tremelimuamb cohort, a CCR7-CD45RA- phenotype appeared and increased within the iNKT-CD4+ and CD8+ subsets after dosing.

Conclusions. Treatment with the anti-CTLA4 antibody tremelimumab induced changes in the percentage of iNKT cells which were more pronounced when co-administered with dendritic cell vaccines. iNKT cells may be a new cell subset mediating in the mechanism of action of CTLA4 blocking antibodies.

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 5518. doi:10.1158/1538-7445.AM2011-5518
Abstract 5523: Adoptive cellular immunotherapy contributes to better survival for NSCLC patients: Case-control study of 395 Japanese patients with advanced NSCLC
Authors: Soejima Kenzo , Iwai Kazuro , Umesato Yoshimasa , Goto Shigenori , Kudo Shoji
Published: June 2012

Adoptive cellular immunotherapy (ITx) targeting various types of carcinoma including the lung is widely used, yet the clinical effectiveness has not been evaluated in large cases of lung carcinoma. So we carried out a case-control study to investigate the effect of ITx for the treatment of advanced non-small cell lung cancer (NSCLC) patients in Japanese population.

Between 2001 and 2006, 163 patients were identified as having advanced NSCLC with ECOG performance status (PS) 0/1 who underwent ITx with or without standard chemotherapy (CTx). The controls were 232 advanced NSCLC patients with PS 0/1 who had standard CTx or BSC alone. Overall survival (OS) and 1- and 2-year survival were obtained with Kaplan-Meyer survival curves and compared using log-rank and generalized Wilcoxon analysis. Multivariate analysis with Cox proportional hazard models was also performed to analyze survival.

The mean age of total population was 64.8 + 10.6 years. There were 251 males and 144 females and 295 adenocarcinoma (Ad) and 74 squamous cell carcinoma (Sq) patients. The mean period and frequency of ITx was 10.2 months and 8.7 times, respectively. Median OS for CTx and ITx + CTx was 15.7 and 20.8 months, respectively. Multivariate analysis with Cox proportional hazard model showed that sex (male vs female) (HR=0.33, p<0.001) and histology (Ad vs Sq) (HR=0.14, p=0.045) were independent predictors of OS. It is revealed that ITx when administered as monotherapy was effective compared to BSC in male with Sq (HR=0.47, p=0.038) and female with Ad (HR=0.53, p=0.016). Additional effect of ITx on CTx was obtained in Ad histology, especially in female (p=0.039).

The present findings suggest that ITx may contribute to better survival for advanced or metastatic NSCLC patients under certain circumstances. These results should be confirmed in large prospective clinical trials.

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 5523. doi:10.1158/1538-7445.AM2011-5523
Abstract 5534: Evaluation of clinical safety and immunogenicity of DPX-0907, a multi-epitope vaccine for the treatment of breast, ovarian and prostate cancers
Authors: Nigam Rita , Karkada Mohan , Weir Genevieve M. , MacDonald Lisa D. , Berinstein Neil , Mansour Marc
Published: June 2012

A successful cancer vaccine needs to overcome tumor-induced immune suppression while enhancing protective Type1-biased tumor-specific immune responses. To achieve this, enhanced vaccine delivery technologies are needed. We have developed a novel liposome-in-oil depot vaccine platform called DepoVaxTM (DPX) which increases the potency of peptide-based cancer vaccines and elicits a strong cytotoxic T cell response. DPX-0907 is a human DPX-based vaccine containing 7 HLA-A2 restricted peptides and is indicated for breast, ovarian and prostate cancer. The antigens were carefully selected with a multi-targeted approach that focuses on proteins involved in pathways that are critical for the survival of a cancer cell. This reduces the likelihood of immune escape through loss of antigen expression/presentation as a tumor responds to vaccine-induced immune pressure. We recently showed that DPX-0907 produces stronger and better sustained immune responses in HLA-A2 transgenic mice than a GM-CSF/ emulsion vaccine. A multicenter phase I clinical trial was initiated in five US clinical sites in March 2010 to evaluate the safety and immunogenicity of DPX-0907 in patients with advanced breast, ovarian or prostate cancer. The open label, dose escalation study recruited patients into one of 2 dose levels (0.25 mL and 1 mL). The vaccine was administered subcutaneously every three weeks for a total of three vaccinations. PBMC's were collected prior to each vaccination and at three time points following the last vaccination. These samples were also used to monitor the immunosuppressive MDSC population in patients receiving the vaccine treatment. In addition, immune monitoring of vaccine-induced responses is based on multi-parametric intracellular cytokine staining of multiple immune cell types and the functional analysis of peptide-MHC-multimer positive CD8 T cells. This first- in-man trial has generated important safety information that support the use of DepoVax for delivering multi-peptide based vaccines. The extensive immune monitoring will aid in the rational design of future DPX-0907 and other DepoVax-based vaccine trials.

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 5534. doi:10.1158/1538-7445.AM2011-5534
Abstract 5542: Chronic TNF-α treatment augments malignant properties of HPV-immortalized oral keratinocytes
Authors: Hong Hannah , Akhavan Jonathan , Kim Reuben , Kang Mo , Park No-Hee , Shin Ki-Hyuk
Published: June 2012

While acute inflammation is a part of the defense response, there have been emerging lines of evidence that suggest a strong link between chronic inflammation and cancer. Human papillomaviruses (HPV) infection is one of key factors in cervical cancer development, and possible link between HPV and oral carcinogenesis have been proposed. However, mechanisms by which HPV and chronic inflammation contribute to oral carcinogenesis have not been fully understood. The objective of this study was to determine the effect of chronic inflammation on malignant progression of HPV-associated oral carcinogenesis. We treated HPV-immortalized oral keratinocytes (HOK-16B) with a major pro-inflammatory cytokine, TNF-α for 4 months and examined the effect of chronic TNF-α treatment on malignant behavior of HOK-16B. Chronic treatment of TNF-α resulted in reduction in differentiation potential, and induction in proliferation potential and in migration ability of the HPV-immortalized oral keratinocytes. cDNA microarray analysis revealed that a subset of genes was significantly downregulated in long-term TNF-α treated cells, and the genes that were involved in differentiation, tumor suppression, and cell-cell junction functions supported the three increased malignant phenotypes, respectively. Our results indicate that chronic inflammation promotes malignant behavior of HPV-immortalized oral keratinocytes, suggesting that chronic inflammation is an important co-carcinogenic factor for HPV-associated oral carcinogenesis.

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 5542. doi:10.1158/1538-7445.AM2011-5542
Abstract 5554: Margin of exposure of genotoxic and carcinogenic furan
Authors: Jestoi Marika , Järvinen Talvikki , Järvenpää Eila , Tapanainen Heli , Virtanen Suvi , Peltonen Kimmo
Published: June 2012

An in-house validated solid-phase microextraction followed by gas chromatography-mass spectrometric determination was used to study furan concentrations in baby-food samples purchased from the Finnish markets (LOD 1.9 ng g−1, LOQ 4.0 ng g−1 and RSTD <20%). The mean levels of furan varied between 4.7 ng g−1 and 90.3 ng g−1 (n=21). The mean concentrations of similar product formulas based on their ingredients were 9.2 ng g−1, 37.0 ng g−1 and 49.6 ng g−1 for fruit-, vegetables- and meat-containing baby-foods, respectively. The consumption of industrial baby-foods in Finland is 172 g/day which results to the furan intake ranging from 0.8 to 15.5 µg/day and exposure of 0.1 to 2.1 µg kg−1 bw/day, respectively. Two extreme worst case scenarios can be deduced from our data: i) the maximum value in consumption of canned baby-foods (883 g/day) and the maximum concentration of furan detected (90.3 µg kg−1) and ii) 95 percentile consumption of canned baby-foods (384 g/day) and the maximum concentration of furan detected (90.3 µg kg−1). These two extreme worst case scenarios gave intakes of 79.7 µg and 34.7 µg, respectively. Applying the benchmark dose rate as well as safety-factor approaches a NOAEL of 0.08 mg kg−1 bw/day for furan can be deduced. If MOE is calculated by using the deduced NOAEL (600 µg/day for 7.5 kg baby) or BMDL10 (1.28 mg kg−1 bw/day) and the worst case exposure scenarios the MOE values of 7.5NOAEL/120BMDL10 and 17.3NOAEL/276BMDL10 can be derived. In the case of low exposure scenario (consumption 172 g/day; furan level 4.7 µg kg−1) the MOE values are 750NOAEL/2030BMDL10. A very low MOE exists in the extreme worst case infant exposures and particularly for such a clear rodent carcinogen (cholangiocarcinoma, hepatocellular adenoma and carcinoma). The MOEs derived clearly indicate that it is now a priority to understand the mode of action for the development of the liver tumours in the rat after exposure to furan and whether this is relevant to man. A significant reduction, however, to the exposure scenarios is provided by the fact that the use of fruit-based baby-foods with low furan content comprises a substantial proportion (mean consumption 78 g/day, maximum consumption 488 g/day and 95 percentile consumption 197 g/day) of the consumption of total industrial baby-foods.

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 5554. doi:10.1158/1538-7445.AM2011-5554