bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1415: Anti-metastatic properties of tumor-entrained neutrophils
Authors: Granot Zvi , Henke Erik , Comen Elizabeth A. , King Tari A. , Norton Larry , Benezra Robert
Published: August 2012

Metastasis represents the final stage in cancer progression and is the primary cause of cancer related mortality. Disseminated cells that are capable of colonizing distant organs and forming metastases therefore present an important therapeutic challenge. In recent years, primary tumors have been shown to prepare distal organs for later colonization of metastatic cells by stimulating organ-specific infiltration of bone marrow derived cells (BMDCs). Here, using mouse models of breast cancer, we demonstrate that neutrophils accumulate in the lung prior to the arrival of metastatic cells. In contrast to other BMDCs that promote metastatic colonization, tumor-entrained neutrophils (TENs), but not control neutrophils, inhibit seeding of metastatic tumor cells in the lungs. TENs protect the pre-metastatic lung by initiating physical contact, generating H2O2 and killing tumor cells. While tumor secreted CCL2 has a pro-tumorigenic effect at the primary site, our data show that it is both required and sufficient for optimal anti-metastatic entrainment at the metastatic site. As tumor-secreted TGFβ blocks cytotoxicity at the primary site, TENs cytotoxicity is limited to the pre-metastatic site where TGFβ levels are low. Additionally, we find that TENs are also present in the peripheral blood of human breast cancer patients prior to surgical resection but not in healthy individuals. Several chemokines known to be increased in the circulation of breast cancer patients have the capacity to induce a cytotoxic phenotype in naïve human neutrophils, providing a possible mechanism for neutrophil entrainment in cancer patients. Taken together, our data show that while tumor-secreted factors contribute to tumor progression at the primary site, they concomitantly induce a neutrophil-mediated inhibitory process at the metastatic site.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1415. doi:1538-7445.AM2012-1415
Abstract 1567: mTERT genetic vaccine chemotherapy combination augment antigen-specific immune response and confer tumor protection in time dependent fashion
Authors: Ugel Stefano , Facciaponte John , Scarselli Elisa , Mennuni Carmela , Monica Nicla La , Coukos George , Facciabene Andrea
Published: August 2012

Successful cancer chemotherapy relies on the comprehensive elimination of tumor cells. However, at clinically tolerated doses, chemotherapeutic drugs usually fail to kill all tumor cells in vivo. Theoretically, to achieve complete eradication, partial tumor killing by chemotherapy should be accompanied by a “bystander effect” in which the immune system recognizes, attacks, and eradicates residual tumor cells. Doxorubicin) is an anthracycline antibiotic that intercalates with DNA, inhibiting its replication. It has been shown that treatment of dendritic cells with Doxorubicin increases their ability to present antigen to Ag-specific T cells in vitro and it is accompanied by upregulation of the Ag-processing machinery (APM) proteins and costimulatory molecules. The telomerase reverse transcriptase, TERT, is an attractive target antigen for cancer vaccine because its expression is reactivated in a conspicuous fraction of human tumors. Critical to the success of combination therapy using TERT vaccine and chemotherapy drugs is a positive (synergistic) interaction between chemotherapy drugs and immune effectors mechanisms. Indeed, activation of antitumor immune responses by vaccine could be antagonized by chemotherapy, if the selected drug exerts immune antagonistic effects. Understanding the dose and the schedule of administration of Doxil (pegylated Doxorubicin) is critical for the design of rational combinations of vaccine and chemotherapy. To test the interactions between TERT vaccine and Doxil we performed a series of experiment using six different therapeutic schedules of Doxil/TERT administration. Interestingly, only two of the Doxil/TERT vaccine combinations resulted in a significant tumor growth inhibition delay which was also accompanied by increase in anti-TERT T cell response. This data unveil new facets of “Chemo immune adjuvancy” of Doxorubicin, and demonstrate how the in vivo efficacy of this combination is impacted by the dosing schedule

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1567. doi:1538-7445.AM2012-1567
Abstract 1596: Effect of combined treatment with ursolic acid (UA) and resveratrol (Res) on skin tumor promotion by TPA
Authors: Cho Jiyoon , Rho Okkyung , Carbajal Steve , Junco Jacob , Slaga Thomas J. , DiGiovanni John
Published: August 2012

In recent years, emerging evidence suggests that cancer chemopreventive agents when combined might be more effective than when given alone. Both UA and Res have been shown to reduce inflammation and tumor development in various tissues. In mouse skin, both compounds have been shown to block skin tumor promotion by TPA and reduce TPA-induced inflammation. In this study, we have further evaluated the effect of UA and Res on skin tumor promotion with emphasis on examining combinations of these agents. For these experiments, UA, Res and combinations of UA + Res were applied topically (various doses) prior to TPA treatment on mouse skin. The combination of UA + Res showed additive and possibly synergistic inhibition of TPA-induced epidermal hyperproliferation as assessed by both epidermal hyperplasia and BrdU labeling index. The effect of UA, Res and the combination of UA + Res on epidermal signaling pathways was also evaluated. The combination of UA + Res significantly inhibited activation of epidermal Akt, NF-κB, p38 MAPK, and JNK in response to TPA treatment compared to the treatment with the individual compounds. The combination of UA + Res also dramatically reduced the induction of epidermal Cox-2 by TPA. Notably, combined treatment with UA and Res induced a dramatic increased phosphorylation of AMPK-α suggesting that AMPK activation may also play a critical role in the ability of the combination to alter skin tumor promotion. Combination treatment during skin tumor promotion showed greater inhibition of tumor multiplicity than with either agent alone. In further experiments, the effect of UA, Res and UA + Res on proliferation of bulge-region keratinocyte stem cells (KSCs) was evaluated. Both UA and Res treatment inhibited TPA-induced proliferation and migration of bulge-region KSCs. Furthermore, the combination of UA + Res appeared to be more effective at blocking proliferation of these cells from the hair follicle when compared with the single compound-treated groups. Taken together, these data suggest that the combination of UA + Res has either additive or synergistic inhibitory effects on keratinocyte proliferation (including KSCs) and various signaling pathways. These effects may explain the greater inhibition of skin tumor promotion by the combination of UA and Res.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1596. doi:1538-7445.AM2012-1596
Abstract 1677: Associations between cigarette smoking with incident colorectal cancer by p53 protein expression in a population-based cohort of older women
Authors: Tillmans Lori , Vierkant Robert , Wang Alice , Samadder N. Jewel , Lynch Charles , Anderson Kristin , French Amy , Haile Robert , Harnack Lisa , Potter John , Slager Susan , Smyrk Thomas , Thibodeau Stephen , Cerhan James , Limburg Paul
Published: August 2012

Background: Cigarette smoking (CS) is an established colorectal cancer (CRC) risk factor. The p53 protein, encoded by the TP53 tumor suppressor gene that is commonly mutated in CRC, is important in cell cycle arrest needed to repair DNA damage or induce apoptosis to prevent tumor propagation. In this prospective cohort study, we examined CS-associated CRC risks by p53 protein expression level in the population-based Iowa Women's Health Study (IWHS). Methods: The IWHS recruited 41,836 randomly selected Iowa women, ages 55-69 years, with a valid driver's license at study entry (1986). CS and other exposure variables were assessed at baseline, by self-report. Incident CRC cases were ascertained by annual linkage with the Iowa Cancer Registry. Archived, paraffin-embedded tissue specimens were collected from 732 CRC cases diagnosed through 12/31/2002. CS was categorized by smoking status (never, current, former), average number of cigarettes per day (1-19, 20-39, > 40) and cumulative pack-years (1-19, 20-39, > 40). P53 protein expression was determined by immunohistochemistry on tissue microarrays. Tumor cores were scored by combining both staining intensity and percent of cells stained to determine negative, low or high p53 protein expression levels. Multivariate Cox regression models were fit to estimate relative risks (RRs) and 95% confidence intervals (CIs). Results: Of the 732 available CRC cases, 486 (66%) had complete CS and p53 data. Associations between CS and CRC subtypes defined by p53 expression level are shown in the Table. Conclusions: These data demonstrate no clear heterogeneity of CS with CRC subtypes defined by p53 expression levels among older women.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1677. doi:1538-7445.AM2012-1677
Abstract 1695: Imaging of the interaction of pancreatic cancer and stellate cells during liver metastasis
Authors: Suetsugu Atsushi , Snyder Cynthia , Moriwaki Hisataka , Saji Shigetoyo , Bouvet Michael , Hoffman Robert M.
Published: August 2012

Pancreatic stellate cells are involved in fibrosis of pancreatic cancer. An understanding of pancreatic cancer-cell interactions with stellate cells is critical to our ability to develop effective anti-tumor therapeutics for pancreatic cancer. We report here imaging of the interaction of pancreatic cancer cells and pancreatic stellate cells in liver metastasis. Human pancreatic cancer cell lines (XPA1 and MiaPaCa-2) were engineered to express green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm. Pancreatic stellate cells, engineered to express RFP, were co-injected with the cancer cells into the spleen of transgenic cyan fluorescent protein (CFP) nude mice. Three hours after splenic injection dual-color pancreatic cancer cells and pancreatic stellate cells were found distributed in the host liver. Seven days after cancer cell-stellate cell co-injection, most pancreatic cancer cells and stellate cells were dead. However, by 28 days after injection, liver metastases were observed in the host CFP nude mice. With the high-resolution intravital imaging afforded by the Olympus FV1000 confocal microscope, the interaction of the dual-colored pancreatic cancer cells and the RFP-expressing pancreatic stellate cells could be clearly imaged in the liver metastasis, suggesting that stellate cells participate in metastasis formation. Our hypothesis is that pancreatic stellate cells form a niche for liver metastasis of pancreatic cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1695. doi:1538-7445.AM2012-1695
Abstract 1699: Breast cancer protein markers in African Americans
Authors: Broome Carolyn W. , Beyene Desta , Esnakula Ashwini K. , Smith Rachel , Abdel-Hameed Enass , Naab Tammey J.
Published: August 2012

The purpose of this study is to characterize protein markers in African American breast tumors that correspond to different tumor subtypes, recurrence, and survival. Tissue microarrays (TMA) have been used because they have the advantage of analyzing numerous samples on a single slide and can be used in clinical pathology laboratories. Protein markers that have been used are estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (Her2), cyclin A2, cytokeratin 5, vimentin, Bcl2, and Ki67. TMA have been prepared and stained for proteins that will distinguish 5 tumor subtypes: luminal A (ER+ and/or PR+ Her2-); luminal B (ER+ and/or PR+ Her2- Cyclin A2+ and/or Ki67+); luminal B Her2+ (ER+ and/or PR+ Her2+); Her2+ (ER- PR- Her2+), and triple negative (ER- PR- Her2-). These subtypes are known to be associated with different relapse-free survival and overall survival. Luminal B tumors have the same ER+PR+HER2- profile as luminal A tumors; however, luminal B tumors have a poor prognosis, whereas luminal A tumors have the best prognosis of all 5 subtypes. Luminal B tumors can be distinguished from luminal A tumors by staining for cell cycle proteins Cyclin A2 or Ki67, which promote cell proliferation. Cyclin A2 was more frequently expressed than Ki67 in tumors with poor prognosis such as luminal B (ER+PR+HER-) and ER-PR-HER2- (triple negative) tumors. Therefore, Cyclin A2+ may better serve to identify luminal B and triple negative tumors with a poor prognosis and thus aid physicians in treatment decisions. The RASSF1A protein has been reported to inhibit the transcription of Cyclin A2. Methylation of the RASSF1A promoter is expected to decrease RASSF1A transcription and thereby increase Cyclin A2 transcription and protein levels. Significantly increased levels of RASSF1A methylation have been observed in this laboratory with AA ER-PR-HER- breast cancer patients compared to mammoplasty samples. Thus, increased Cyclin A2 protein staining correlated with increased RASSF1A methylation. This is one molecular explanation for elevated cyclin A2 protein levels in triple negative tumors. Discovery of molecular markers and subtypes that are most prevalent in African Americans could lead to a better treatment, targets for therapy, and understanding of the factors contributing to higher mortality in this group compared to other groups.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1699. doi:1538-7445.AM2012-1699
Abstract 1707: A real-time PCR assay for detecting EGFR mutations in formalin-fixed paraffin-embedded tissue (FFPET) specimens of non-small cell lung cancer (NSCLC)
Authors: O'Donnell Patrick , Ferguson Jane , Shyu Johnny , Current Robert , Rehage Taraneh , Tsai Julie , Christensen Mari , Tran Ha Bich , Chien Shih-Chang , Wei Wen , Lawrence H.Jeffrey , Soviero Stephen
Published: August 2012

EGFR mutations identify patients with NSCLC who have a high likelihood of benefiting from first-line treatment with anti-EGFR tyrosine kinase inhibitors. Sanger sequencing is widely used for mutation detection but can be time-consuming, and has limited sensitivity for low levels of mutations. We describe the analytic performance of the cobas EGFR Mutation Test, a multiplex, 3-reaction real-time PCR assay designed to detect 41 mutations in exons 18, 19, 20 and 21. The mutations detected and the mutation report calls are listed below: The amount of DNA required for the assay (150 ng) can typically be isolated from a single 5-micron FFPET section, and the test can be performed in < 8 hours. Analytic sensitivity was assessed using DNA blends from NSCLC FFPET tumor sections. A >95% hit rate was obtained in blends with >5% mutant alleles for L858R and exon 19 deletions as determined by 454 sequencing (quantitative massively parallel pyrosequencing) at a total DNA input of 150ng, or 50 ng per PCR amplification. The cobas test was compared to 2x bidirectional Sanger sequencing using a set of 152 NSCLC FFPET specimens. The overall percent agreement (OPA) between the 2 methods was 96.7% (negative agreement - NPA 97.5%; positive agreement - PPA 95.8%). Specimens with discordant cobas EGFR Test and Sanger results were analyzed by 454 and a revised agreement analysis was performed based on the composite results of the 3 assays. The revised OPA was 98.7% (NPA 98.8%; PPA 98.6%). The call repeatability of a panel of NSCLC FFPET specimens was 98% when tested with two operators, instruments, and reagent lots. Necrotic tissue, hemoglobin, triglycerides, and common respiratory organisms did not interfere with the assay. The test showed no cross reactivity with the corresponding exon sequences from the HER2, HER3, and HER4 genes. These analytic studies demonstrate that the cobas EGFR Mutation Test is a sensitive, accurate and reproducible assay.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1707. doi:1538-7445.AM2012-1707
Abstract 1728: Genetic variations in epidermal growth factor receptor pathway predict recurrence and response to chemotherapy in early stage non-small cell lung cancer
Authors: Kim Eric S. , Ye Yuanqing , Vaporciyan Ara A. , Xing Jinliang , Huang Maosheng , Gu Jian , Roth Jack A. , Lippman Scott M. , Wu Xifeng
Published: August 2012

Purpose: We hypothesized that genetic variants within EGFR pathway would have significant predictive value for recurrence and response to chemotherapy after curative resection in early-stage NSCLC. Methods: This study included 467 patients with histologically confirmed NSCLC who were enrolled from 1995 to 2008 in an ongoing, prospective epidemiologic lung cancer study at MD Anderson Cancer Center. A total of 387 single nucleotide polymorphisms (SNPs) within 26 genes from EGFR pathway were genotyped in patients who were treated with surgery only (N=340) or surgery plus chemotherapy (N=127). The risk of recurrence was estimated as hazard ratios (HRs) and 95% confidence intervals (CIs) using a multivariate Cox proportional hazard regression model. Results: We identified 5 top SNPs that significantly (P<0.05) predicted risk of recurrence in both surgery only and surgery plus chemotherapy groups. To identify a subgroup of patients who may benefit from adjuvant chemotherapy, we divided these 5 SNPs into two different groups according to varying hazard ratios for the analysis performed in surgery only or surgery plus chemotherapy group; A (2 SNPs)=should receive surgery only (HR<1 in surgery only and HR>1 in surgery+chemotherapy); B (3 SNPs)=should receive chemotherapy in addition to surgery (HR>1 in surgery only and HR<1 in surgery+chemotherapy). Cumulative genotype analysis reveals that patients with 1 or 2 SNPs from Group A had risk of recurrence that was 0.57-fold that of the reference group without any of these two SNPs (HR=0.57; 95% CI=0.34-0.96; P=0.035). However, if patients with the same 1 or 2 SNPs undergo chemotherapy, the risk of recurrence increases to 3.3-fold that of the reference group (HR=3.28; 95% CI=1.51-7.12; P=0.003). On the other hand, patients with one or greater number of SNPs from Group B after surgery only had 2.3-fold increased risk of recurrence compared to the reference group without any of these SNPs (HR=2.30; 95% CI=1.36-3.88; P=0.002). However, with addition of chemotherapy the risk of recurrence in patients with the same SNPs decreased significantly to 0.24-fold that of the reference group (HR=0.24; 95% CI=0.12-0.51; P=0.001). Conclusions: Our proposed SNPs from EGFR pathway may help identify a subgroup of patients at high risk of recurrence after resection and guide decision for adjuvant chemotherapy in early-stage NSCLC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1728. doi:1538-7445.AM2012-1728
Abstract 1763: A novel synthetic alkylating agent inducing DNA damages is associated with distinct DNA repair pathways
Authors: Wang Hui-Chun , Kuo Ching-Ying
Published: August 2012

Alkylating agents are a commonly used category of chemotherapy drugs for a verity type of malignancy. They kill cells by forming DNA adducts and interfering DNA processes if not to being removed. In respect to the types of mono- or bi-functional DNA alkylation, different classes of DNA repair processes are involved. In this study, a new DNA-directed alkylating agent BO738 was investigated. We emphasized to confirming its ability of DNA damage, and revealing which kinds of DNA repair mechanisms to be involved in BO738-induced damage. Our results proved BO738 is a bi-functional alkylating DNA damage agent, evidences including BO738 was able to induce phosphorylation of Chk1, Chk2 and p53, and elevated more potent of FANCD2 monoubiquitination, a hallmark of DNA-crosslink damage, than induced by BCNU. Followed with the finding of DNA damage response, as expected, cells that abolish in removal of BO738-induced DNA damage are link to at least base excision repair, double strand break repair and MGMT-mediate direct repair machineries. In conclusion, we provide a foundation to understand the molecular action of BO738 in subcellular environment, and according that BO738 displays comparable ability in tumor cytotoxicity than BCNU, our study highlighting a therapeutic potential in cancer chemosensitization.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1763. doi:1538-7445.AM2012-1763
Abstract 1789: Preclinical profile of novel and potent c-Met kinase inhibitors
Authors: Vakkalanka Swaroop , Muthuppalaniappan Meyyappan , Govindarajulu Babu , Varanasi Kanthikiran , Veeraraghavan Sridhar , Kuppireddi Sumalatha , Viswanadha Srikant , Dhanapalan Nagarathnam , Bhavar Prashant
Published: August 2012

Background: c-Met is a proto-oncogene that encodes the protein Met with intrinsic tyrosine kinase activity. Aberrant Met kinase activity triggers a series of unwarranted phosphorylation events and signalling processes that ultimately lead to the development of cancer. Alteration of the Met kinase signalling cascade represents an attractive approach aimed at blocking invasion and metastasis of cancer cells. Herein, we describe the biological and pharmacokinetic properties of representative molecules from a series of novel and small molecule inhibitors with scope to be further developed as clinical candidates for cancers mediated by dysregulated Met kinase activity. Methods: Met Kinase activity of test compounds was determined using an HTRF® KinEASE assay kit (Cisbio, Bedford, MA) with modifications. Met-dependent anti-proliferative effect was determined in MKN-45 cells. Inhibition of constitutive Met kinase phosphorylation in MKN-45 and NCI-H441 cells was measured in an ELISA assay. Subsequently, effect of the compounds on Akt phosphorylation, a downstream marker in the Met signalling cascade, was determined. Metabolic stability of the compounds was evaluated in microsomes obtained from mouse, rat, dog, monkey, and human. Results: Among the compounds evaluated, RP1269 and RP1316 demonstrated remarkable potency against the purified Met kinase enzyme (20.17 & 40.5 nM) as well as in an MKN-45 cell proliferation assay (18.0 & 2.3 nM). In addition, the compounds caused a significant reduction in constitutive Met kinase phosphorylation in MKN-45 (11.5 & 33.3 nM) and NCI-H441 (2.2 & 4.1 nM) cells. As a consequence, Akt phosphorylation was inhibited at half-maximally in MKN-45 and NCI-H441 cells at <100 nM and <50 nM respectively. Further, the compounds exhibited a favourable ADME profile across the species studied. Conclusions: Our findings demonstrate that RP1269 and RP1316 are potent Met kinase inhibitors with efficacy values comparable to existing Met kinase inhibitors in development. On lines with selective inhibitors, the compounds display anti-proliferative effect only in cells with amplification of the Met kinase gene. The compounds are currently being tested for efficacy and target inhibition in various xenograft models. Clinical candidate shall be nominated by 2012.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1789. doi:1538-7445.AM2012-1789
Abstract 1800: Targeted therapy using saracatinib adjunctive to castration inhibits progression to castration-resistant prostate cancer in a murine model
Authors: Yang Joy C. , Hu Brian , Durbin-Johnson Blythe , Gao Allen C. , Kung Hsing-Jien , Evans Christopher P.
Published: August 2012

Introduction: Prostate cancer treatment with androgen deprivation is typically efficacious for two years prior to the development of castration resistant disease (CRPC). The Src family kinases (SFK) are upregulated with androgen deprivation and have been implicated in the progression to CRPC. Saracatinib is a specific SFK inhibitor that inhibits castration resistant growth and metastases in an animal model using LNCaP cells overexpressing the neuropeptide gastrin-releasing peptide. We test the hypothesis that saracatinib given immediately after androgen deprivation inhibits castration resistant tumor recurrence using a CWR22 xenograft model. Materials and Methods: CWR22 prostate cancer xenografts were injected subcutaneously into nude mice primed with testosterone pellets (21-day release). Twenty-six mice were castrated after adequate tumor development (day 0). Mice in the treatment arm were administered saracatinib from day 7 to day 150. Mice were sacrificed at days 0, 3, 30 and 150. Tumors and sera were collected for analysis including tumor weight, serum testosterone, serum PSA and gene-profile studies. The data was analyzed using the t-test and analysis of variance. Results: CRPC recurrence was significantly inhibited with the administration of saracatinib. The mean weight of tumor recurrence was 0.18 grams with saracatinib compared to 3.20 grams in the control group (p=0.015). Saracatinib was associated with a reduction in serum PSA (1.6 versus 14.7 ng/dl) and testosterone (21.1 versus 24.1 pg/ml) compared to controls, though statistical significance was not reached (p=0.08 and p=0.63, respectively). Gene expression of signaling kinases and their downstream olecules including Src, Etk, FAK, JAK, Stat3, c-myc, β-catenin, NF-κB, Akt, and mTOR is being compared between time points. Conclusions: Saracatinib significantly inhibits castration resistant tumor recurrence when started with androgen deprivation. Additional investigation into the genetic and molecular changes induced by saracatinib with gene microarray and polymerase chain reaction is ongoing. Saracatinib may have a role in combination with androgen deprivation to delay the onset of castration resistant disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1800. doi:1538-7445.AM2012-1800
Abstract 2411: The epithelial-mesenchymal transition of gastric cancer cells was stimulated by TGFβR signaling in hypoxia
Authors: Matsuoka Junko , Yashiro Masakazu , Aomatsu Naoki , Hirakawa Toshiki , Hasegawa Tsuyoshi , Fukuoka Tatsunari , Morisaki Tamami , Kubo Naoshi , Tanaka Hiroaki , Muguruma Kazuya , Yamada Nobuya , Ohira Masaichi , Ishikawa Tetsuro , Hirakawa Kosei
Published: August 2012

Introduction: Epithelial mesenchymal transition (EMT) is a cellular process during which epithelial cells acquire mesenchymal properties while losing cell-cell interactions and apicobasal polarity. EMT is considered to be correlated with malignancy of cancer cells and responsible for cancer invasion and metastasis. Patients with gastric cancer show a poor prognosis because of frequent metastasis. We previously reported that distant metastasis was associated with hypoxia in gastric cancer. Therefore, we investigated the effect of hypoxic condition on EMT of gastric cancer cells. Materials and Methods:Seven gastric cancer cell lines derived from gastric cancer were used. Cells were cultured in normoxia (21% O2) or hypoxia (1% O2) for 24h. EMT rate was evaluated as the percentage of spindle-shaped cells of total cells. The expression level of TGFβ and TGFβ receptor was evaluated by real time RT-PCR. Effect of several inhibitors on the EMT was evaluated by cell morphology. The TGFβ1 level of the cell culture supernate was measured by a quantitative sandwich enzyme immunoassay technique. Results: Hypoxia stimulated EMT of OCUM-2MD3 and OCUM-12 cells, but not that of other cell lines. The level of TGFβ expression was increased significantly (p<0.01) under hypoxia in comparison with normoxia. The level of TGFβ receptor expression was increased in OCUM-2MD3 cells, but not OCUM-2M cells. TGFβR inhibitor, SB431542, significantly suppressed EMT of OCUM-2MD3 (p=0.03) and OCUM-12 (p<0.01). In OCUM-2MD3 and OCUM-12, the quantity of TGFβ1 in cell culture supernatant significantly increased under hypoxia compared to normoxia, but not OCUM-2Mcells. Conclusion: Hypoxia stimulates the EMT of gastric cancer cells via TGFβ/ TGFβ receptor signaling. TGFβ receptor inhibitor might be promising for the treatment of metastasis of gastric cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2411. doi:1538-7445.AM2012-2411
Abstract 2417: Oncogenic properties shared by all Snail family members
Authors: Gras Baptiste , Chassot Christelle , Puisieux Alain , Ansieau Stéphane
Published: August 2012

The epithelial to mesenchymal transition (EMT) is a latent embryonic process promoting cell migration by transiently affording epithelial cells a mesenchymal phenotype, motility and a survival advantage. The inappropriate activation of this program in adult cells is associated with several pathologies including tumor development where EMT promotes cancer cell dissemination and multidrug resistance development. We have recently demonstrated that EMT-inducers, beyond their prometastatic potential, facilitate the malignant transformation of human mammary epithelial cells in vitro and promote breast carcinogenesis in vivo. Although their ability to alleviate senescence and apoptosis failsafe program induction unquestionably contributes to their oncogenic potentials, we sought to investigate whether EMT inducers share additional properties. To this end, the activities of all three Snail members were examined. Likewise SNAI1 and SNAI2, SNAI3 expression is aberrantly activated in cancers, especially in mammary carcinomas. Ectopic expression of all three proteins in mammary epithelial cells induces their commitment into EMT, provides cells with a survival advantage in low adherent conditions and promotes their neoplastic transformation, with a similar gradient of efficiencies. Interestingly, this efficiency parallels with their ability to upregulate intracellular signaling pathways. We will update on the progress of our work aimed at understanding how these dysregulations impact on their oncogenic and prometastatic potential.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2417. doi:1538-7445.AM2012-2417
Abstract 2422: Early features of EMT in Abcb4−/
−-cholangiocytes: A novel cellular model for testing antimetastatic drugs
Authors: Arbizu Amaia , Gil-Puig Carmen , Cabello Juan , Lecanda Jon
Published: August 2012

Discovering novel drugs for epithelial tumors remains a challenge since cellular events underlying the onset of carcinoma progression are largely unknown. We previously reported the therapeutic effects of oral 5′-methylthioadenosine in the Abcb4−/− mouse (Latasa et al, PLoS ONE 2010: e15690), a clinically relevant model of chronic liver disease leading to carcinoma development. Aiming to gain insight into malignant cellular traits, we then generated primary cultures of intrahepatic bile duct cells from this Abcb4−/− mouse model. We found that Abcb4−/−-cholangiocytes exhibit a fibroblastoid-like appearance which is accompanied by diminished expression of epithelial hallmarks (CK19), and a concomitant up-regulation of mesenchymal markers such as Snail1. The trans-epithelial-electrical-resistance analyses indicated that whereas confluent monolayers of normal cholangiocytes retained the epithelial polarity, Abcb4−/−-cholangiocytes fail to repolarize. Abcb4−/−-cholangiocytes proliferated at reduced growth rates (p<0.05), formed a higher number of colonies in soft agar (p<0.01) and were less sensitive to antiproliferative effect of TGFβ1 (p<0.05). Consistent with EMT characteristics, Abcb4−/−-cholangiocytes induced TGFβ isoforms and were more sensitive to TGFβ1-signaling. Collectively, this data suggests that Abcb4−/− cholangiocytes acquire EMT features that may be largely regulated in vivo by TGFβ1. This original bile ductular cell line of Abcb4−/−-cholangiocytes will be useful for testing compounds that may interfere with metastatic malignancy of EMT.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2422. doi:1538-7445.AM2012-2422
Abstract 2427: The stress response controls the interorgan glutathione/interleukin-6 cycling activity: A systemic signaling mechanism promoting metastases growth.
Authors: Estrela Jose M. , Obrador Elena , Mena Salvador , Rodriguez Maria L. , Pellicer Jose A. , Asensi Miguel , Vallés Soraya L. , Benlloch Maria
Published: August 2012

B16 melanoma F10 (B16-F10) cells with high glutathione (GSH) content show very high metastatic activity in vivo. An intertissue flow of GSH, where the liver is the main reservoir, increases GSH content in metastatic cells and promote their growth. We studied possible tumor-derived molecular signals that could activate GSH release from hepatocytes. GSH efflux increases in hepatocytes isolated from mice bearing liver or lung metastases, thus suggesting a systemic mechanism. Fractionation of serum-free conditioned medium from cultured B16-F10 cells and monoclonal antibody-induced neutralization techniques facilitated identification of interleukin (IL)-6 as a tumor-derived molecule promoting GSH efflux in hepatocytes. IL-6 activates GSH release through a methionine-sensitive/organic anion transporter polypeptide 1- and multidrug resistance protein 1-independent channel located on the sinusoidal site of hepatocytes. Specific siRNAs were used to knock down key factors in the main signaling pathways activated by IL-6, which revealed a STAT3-dependent mechanism. Our results show that IL-6 (mainly of tumor origin) facilitates GSH release from hepatocytes and its interorgan transport to metastatic growing foci. Metastatic tumor activated the hypothalamic-pituitary-adrenal axis, thus increasing expression of hypothalamic corticotropin releasing factor and plasma levels of adrenocorticotropin hormone, corticosterone, and cathecolamines. Corticosterone and norepinephrine increased IL-6 expression and synthesis in metastatic cells, thus promoting the interorgan GSH/IL-6 cycling activity. Our results suggest possible mechanisms of cross-talk between metastases and the central nervous system of the host.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2427. doi:1538-7445.AM2012-2427
Abstract 2431: 89Zr-bevacizumab PET as an early biomarker for response to everolimus treatment in an ovarian cancer xenograft model
Authors: van Scheltinga Anton G.T. Terwisscha , van der Bilt Arne R.M. , Timmer-Bosscha Hetty , Schröder Carolien P. , Pot Linda , Kosterink Jos G.W. , van der Zee Ate G.J. , Hooge Marjolijn N. Lub-de , de Jong Steven , de Vries Elisabeth G.E. , Reyners An K.L.
Published: August 2012

The mammalian target of rapamycin (mTOR) pathway is activated in the majority of ovarian cancers and is involved in tumor angiogenesis. Inhibitors of mTOR, like everolimus, are potentially interesting drugs as they can exert antitumor activity in part through reducing downstream vascular endothelial growth factor-A (VEGF-A) production. We investigated whether early effects of everolimus treatment could be monitored with 89Zr-bevacizumab positron emission tomography (VEGF-PET). Methods: The effect of everolimus on VEGF-A secretion was determined in three human ovarian cancer cell lines and in A2780luc+ ovarian cancer cells xenografted subcutaneously in BALB/c mice. Mice received daily everolimus (10 mg/kg intraperitoneally) for 14 days. PET scans with the tracer 89Zr-labeled bevacizumab were performed to monitor tumor VEGF-A expression before (baseline) and after treatment. Images were obtained 6 days after tracer injection. Tracer uptake was quantified and expressed as mean standardized uptake values (SUVmean). For ex vivo 89Zr-bevacizumab biodistribution and correlative tissue analyses, control animals were sacrificed after the baseline scans. Tumor VEGF-A levels were measured with ELISA in tumor lysates and mean vascular density (MVD) was determined with immunohistochemistry. Results: Everolimus treatment lowered VEGF-A levels in the supernatant of all cell lines. Everolimus lowered 89Zr-bevacizumab tumor uptake by 21.7 ± 4.0% (SUVmean 2.26 ± 0.18 versus 2.89 ± 0.20, p < 0.01). Ex vivo 89Zr-bevacizumab biodistribution showed less tracer uptake in the tumors of treated compared to control animals (7.78 ± 0.84 %ID/g versus 14.02 ± 1.68 %ID/g, p < 0.01), while no differences were observed for other tissues. VEGF-A protein levels in tumor lysates were lower in treated versus untreated tumors (p = 0.04), as was the MVD (p < 0.01). Conclusion: 89Zr-bevacizumab PET showed reduced tumor VEGF-A levels in vivo in response to everolimus therapy, coinciding with inhibition of tumor angiogenesis. Currently there are 2 clinical trials ongoing to study the value of 89Zr-bevacizumab PET to monitor tumor VEGF-A levels as an early biomarker of response to mTOR inhibitor therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2431. doi:1538-7445.AM2012-2431
Abstract 2434: A genetically engineered mouse for imaging of apoptosis in a tissue specific manner
Authors: Galbán Stefanie , Jeon Yong Hyun , Sharkey Lisa M. , Hoff Benjamin A. , Galban Craig J. , Ross Brian D. , Rehemtulla Alnawaz
Published: August 2012

The importance of the apoptotic machinery is exemplified in a number of disease processes. For example, inhibition of apoptosis can result in a number of cancers, autoimmune diseases, inflammatory diseases, and viral infections. Cancer is characterized by dysregulated cell proliferation and altered cell death, which constitutes a common basis for neoplastic evolution. The most implicit and clinically attractive anticancer strategies, therefore, consist of eliminating tumor cells by preventing their expansion and ultimately inducing apoptotic cell death. We have developed a transgenic mouse model wherein Caspase 3 mediated cell death can be imaged in real time and non-invasively utilizing a luciferase based biosensor. Upon Cre-mediated recombination, transgene expression containing the Caspase 3 biosensor is achieved in a cell or tissue specific manner. Here we show that expression of the Caspase 3 biosensor can be achieved in several tissues. In addition, we demonstrate in mouse models of cancer, that the ability to dynamically and sensitively image the activation of the Caspase 3 provides an opportunity to understand the dynamics of cell death in response to specific drugs or combination therapies. We also provide results demonstrating the utility of the technology in evaluating the efficacy of cancer therapeutics in cancer stem cells, a population that is rare and transient.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2434. doi:1538-7445.AM2012-2434
Abstract 244: Characterization of a candidate tumor suppressor gene DIRAS1 in esophageal squamous cell carcinoma
Authors: Zhu Yinghui , Chen Polly Leilei , Fu Li , Liu Haibo , Xie Fajun , Guan Xin-Yuan
Published: August 2012

Loss of 19p is one of the most frequent alterations in many malignancies including esophageal squamous cell carcinoma (ESCC), suggesting the existence of a tumor suppressor gene (TSG) within the frequently deleted region. In this study we describe the identification and characterization of one candidate TSG, DIRAS family, GTP-binding RAS-like 1 (DIRAS1), at 19p13.3. DIRAS1 downregulation occurred in 34 of 75 (43.33%) primary ESCCs and 5/9 (55.6%) of the ESCC cell lines. Immunohistochemistry detection demonstrated that the down-regulation DIRAS1 expression was an independent prognostic factor of ESCC and associated with poor survival in ESCC. Functional studies showed that Ectopic expression of DIRAS1 in ESCC cells inhibited cell proliferation, foci formation, and tumor formation in nude mice. The tumor-suppressive mechanism of DIRAS1 was associated with its proapoptotic role in a mitochondrial-dependent manner by down-regulation of phosphorylated BAD and activating caspase-9, caspase3 and PARP via ERK- and p38-dependent signaling pathway. In addition, down-regulation of DIRAS1 protein was significantly correlated with ESCC lymph node metastasis (P = 0.003), which was associated with its function in inhibiting cell migration and invasion by down-regulation of MMP-2 and MMP-9 via ERK- and p38-dependent signaling pathway. In conclusion, our findings suggest that DIRAS1 plays an important suppressive role in the development and progression of ESCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 244. doi:1538-7445.AM2012-244
Abstract 2450: Optimization of spontaneous metastasis incidence and quantification in human tumor xenograft models using bioluminescence imaging
Authors: Meade Mary Anne , Baugher Meridith , Baranski Jeni , Castorena Jeremy , Trachet Erin , Lister Deanne R. , Leopold Dick , McConville Patrick
Published: August 2012

Introduction: Spontaneous metastasis models are sought after in order to assess the potential of therapies aimed at prevention or treatment of primary tumor metastases. While some human tumor xenograft mouse models show spontaneous metastasis, few show high tissue specific incidence. Commonly the growth of the inherently more advanced primary tumor also limits the ability to characterize far less advanced metastases. Bioluminescence imaging provides a quantitative and convenient means for assessing location, incidence and progression of metastases using metastatic luciferase expressing tumor lines. However, substantially greater light signal from the primary tumor inhibits the ability to find and track much smaller metastasis signals. Several approaches to optimizing metastasis incidence and quantification, and controlling primary tumor growth were used and compared in a MDA-MB-231-luc-D3H2LN xenograft model. Methods: To assess both mouse strain dependence and implant site dependence of primary tumor metastasis, MDA-MB-231-luc-D3H2LN cells (2x106) were implanted in either the mammary fat pad, the sacral region or the quadriceps in several mouse strains, including outbred nu/nu, SHO and nd/bg/xid. To control primary tumor growth in order to facilitate metastasis quantification, both surgical excision and radiation based growth inhibition of of the primary tumors were used. In all cases, whole body bioluminescence imaging was used to quantify metastasis incidence and growth. Shileding of the primary tumor was used in order to characterize smaller metastases. Results and Discussion: While the MDA-MB-231-luc-D3H2LN mammary fat pad implant model has been shown the metastasize spontaneously, tissue specific incidence is generally < 100% and the ability to quantify metastases severely limited by the substantially greater light signal overwhelming much smaller metastasis signals, even when primary tumor shielding is used. In this study, both surgical excision and radiation based primary tumor growth inhibition enhanced the ability to detect metastases in a variety of tissues, including lymph nodes and lungs. The mammary fat pad implant site and the SCID Beige strain provided the highest spontaneous metastasis incidence. Future work will test radiation timing and dose to further optimize metastasis quantification in this and other spontaneous metastasis models.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2450. doi:1538-7445.AM2012-2450
Abstract 2538: HIF1α regulated expression of XPA contributes to cisplatin resistance in lung cancer
Authors: Liu Yanbin
Published: August 2012

Factors regulating nucleotide excision repair (NER) likely contribute to the heterogenous response of advanced stage lung cancer patients to drugs such as cisplatin. Studies to identify the genes in the NER pathway most closely associated with resistance to cisplatin have not been conclusive. We hypothesized that Xeroderma pigmentosum complementation group A (XPA) because of its dual role in sensing and recruiting other DNA repair proteins to the damage template would be critical in defining sensitivity to cisplatin. Studies were conducted to identify factors regulating transcription of XPA, to assess its role in modulating sensitivity to cisplatin, and its expression in primary lung tumors. HIF1α was found to bind with strong affinity to a hypoxia response element sequence in the promoter of XPA. Modulating expression of HIF1α by siRNA or cobalt chloride markedly reduced or increased transcription of XPA in lung cancer cell lines, respectively. Protein levels of XPA were strongly correlated with sensitivity to cisplatin (r = 0.868; p < 0.001) in cell lines and sensitivity could be increased by siRNA depletion of XPA. Expression of XPA determined in 54 primary lung tumors was increased on average 5.2-fold when compared to normal bronchial epithelial cells and correlated with levels of HIF1α (r = 0.58; p < 0.01). Together, these studies identify XPA as a novel target for regulation by HIF1α whose modulation could impact lung cancer therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2538. doi:1538-7445.AM2012-2538