bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4600: Analysis of clonal evolution in cancer using whole exome sequence data reveals that subclonal driver mutations predict poor prognosis in chronic lymphocytic leukemia.
Authors: Carter Scott L. , Landau Dan-Avi , Stojanov Petar , McKenna Aaron , Cibulskis Kristian , Lawrence Michael S. , Lohr Jens , Stevenson Kristen , Neuberg Donna , Meyerson Matthew , Wu Catherine J. , Getz Gad
Published: August 2014

Clonal evolution is a key feature of cancer progression and relapse. We present a computational technique for analyzing whole exome sequence data to measure the fraction of cancer cells harboring each somatic mutation and resolve subclonal cell populations. We applied our methods to 149 chronic lymphocytic leukemia (CLL) samples to classify driver mutations as predominantly clonal or subclonal, corresponding to initiating and progression events in CLL evolution. We identified driver mutations as predominantly clonal (e.g., MYD88, trisomy 12 and del(13q)) or subclonal (e.g., SF3B1, TP53), corresponding to earlier and later events in CLL evolution. We sampled leukemia cells from 18 patients at two timepoints and found that 10 of 12 CLL cases treated with chemotherapy (but only 1 of 6 without treatment) underwent clonal evolution, predominantly involving subclones with driver mutations (e.g., SF3B1, TP53) that expanded over time. Furthermore, presence of a subclonal driver mutation was an independent risk factor for rapid disease progression. Our methods uncover patterns of clonal evolution in cancer, providing insights into its stepwise transformation and linking the presence of subclones with adverse clinical outcome. Because our methods require only whole exome sequence data, they are readily applicable to a large corpus of approximately 6,000 sequenced cancer exomes, and are ideally suited for application in future exome-based clinical cancer sequencing pipelines. We present additional application of our methods to analysis of prostate cancer, multiple myeloma, and glioblastoma multiforme datasets.

Citation Format: Scott L. Carter, Dan-Avi Landau, Petar Stojanov, Aaron McKenna, Kristian Cibulskis, Michael S. Lawrence, Jens Lohr, Kristen Stevenson, Donna Neuberg, Matthew Meyerson, Catherine J. Wu, Gad Getz. Analysis of clonal evolution in cancer using whole exome sequence data reveals that subclonal driver mutations predict poor prognosis in chronic lymphocytic leukemia. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4600. doi:10.1158/1538-7445.AM2013-4600
Abstract 4609: Novel phosphorylation and ubiquitination sites regulate ROS-dependent degradation of c-FLIP and sensitization of cancer cells to TRAIL.
Authors: Wilkie-Grantham Rachel P. , Matsuzawa Shu-Ichi , Reed John C.
Published: August 2014

The cytosolic protein c-FLIP (cellular Fas-associated death domain-like interleukin 1β-converting enzyme inhibitory protein) is an inhibitor of death receptor-mediated apoptosis that is up-regulated in a variety of cancers, contributing to apoptosis resistance. Several compounds found to restore sensitivity of cancer cells to TRAIL, a TNF family death ligand with promising therapeutic potential, act by targeting c-FLIP ubiquitination and degradation by the proteasome. The generation of reactive oxygen species (ROS) has been implicated in c-FLIP protein degradation. However, the mechanism by which ROS post-transcriptionally regulate c-FLIP protein levels is not well understood. We show here that treatment of prostate cancer PPC-1 cells with the superoxide generators menadione or paraquat down-regulates c-FLIP long (c-FLIPL) protein levels, which is prevented by the proteasome inhibitor MG132. Furthermore, pretreatment of PPC-1 cells with a ROS scavenger prevented ubiquitination and loss of c-FLIPL protein induced by menadione or paraquat. We identified lysine 167 as a novel ubiquitination site of c-FLIPL important for ROS-dependent degradation. We also identified threonine 166 as a novel phosphorylation site and demonstrate that T166 phosphorylation is required for ROS-induced K167 ubiquitination. The mutation of either T166 or K167 was sufficient to stabilize c-FLIP protein levels in PPC-1, HEK293T, and HeLa cancer cells treated with menadione or paraquat. Accordingly, expression of c-FLIP T166A or K167R mutants protected cells from ROS-mediated sensitization to TRAIL-induced cell death. Our findings reveal novel ROS-dependent post-translational modifications of c-FLIP that regulate c-FLIP protein degradation and subsequent sensitization of cancer cells to TRAIL.

Citation Format: Rachel P. Wilkie-Grantham, Shu-Ichi Matsuzawa, John C. Reed. Novel phosphorylation and ubiquitination sites regulate ROS-dependent degradation of c-FLIP and sensitization of cancer cells to TRAIL. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4609. doi:10.1158/1538-7445.AM2013-4609
Abstract 4627: Role of intratumoral cell heterogeneity on therapeutic efficacy in glioblastoma.
Authors: Chakravarty Debyani , Pedraza Alicia , Liu Angela H. , Cotari Jesse , Altan-Bonnet Grégoire , Brennan Cameron W.
Published: August 2014

Glioblastoma (GBM), the most common and lethal malignancy of the brain, is typified by high degrees of histologic and molecular heterogeneity. The majority of GBM harbor amplification and/or mutations of receptor tyrosine kinases (RTKs), most frequently EGFR (40-50%) or PDGFRA (∼15%). We recently documented that a subset of glioblastoma harbors independent focal amplification of two or more RTKs, most commonly PDGFRA and EGFR. This phenomenon lends genetic evidence to support that co-expression of more than one RTK in the same cell serves a functional purpose in conferring selective growth advantage to GBM.

In this study we demonstrate that EGF stimulates endogenous interaction between activated EGFR and PDGFRA, assessed using reciprocal coimmunoprecipitation and proximity ligation assays in patient-derived GBM tumor-sphere lines of multiple genotypes. EGF leads to phosphorylation of PDGFRA Y720. This transactivation and subsequent activation of Shp2 are abolished by EGFR inhibitors gefitinib or lapatinib at low concentrations. Evidence of EGFR-PDGFRA interaction was found in the majority of GBM tumorsphere lines where both receptors were expressed. We used multichannel phospho-FACS in a panel of tumorsphere lines to characterize the cell-to-cell heterogeneity of EGFR and PDGFRA expression levels and how these levels affect p-Akt and p-ERK baseline activity, response to ligands and response to targeted receptor inhibition. Indeed, high expression of both EGFR and PDGFRA identifies tumor cells with elevated MAPK and PI3K pathway activity. Notably, these tumor cells have high downstream pathway activation in the absence of explicit stimulation by ligand and appear to be refractory to dual RTK inhibition. Taken together, these data underscore the role of tumor cell RTK heterogeneity in therapeutic resistance to RTK inhibitors in GBM. This study also highlights a possible mechanism that heterotypic RTKs in the same cell may utilize to achieve growth advantage.

Citation Format: Debyani Chakravarty, Alicia Pedraza, Angela H. Liu, Jesse Cotari, Grégoire Altan-Bonnet, Cameron W. Brennan. Role of intratumoral cell heterogeneity on therapeutic efficacy in glioblastoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4627. doi:10.1158/1538-7445.AM2013-4627
Abstract 4636: AMF-1c-120: an antibody specific for misfolded prion protein expressed on ovarian cancer cells.
Authors: Uger Marni D. , Chai Viengthong , Ciolfi Veronica , Chen Hui , Plawinski Ewa , Mutukura Tapfuma , Sage Andrew , Demers Ryan , Lau Leo , Lee Pierre , Liu Xiuwen , Guan Jun , Wang Yuzhuo , Guest William C. , Plotkin Steven S. , Cashman Neil R.
Published: August 2014

We tested the hypothesis that cancer cells might display misfolded protein molecules at the cell surface, due to oxidative covalent modifications, defective glycosylation, and/or other factors relevant to cancer. We developed a computational algorithm to predict regions of proteins which were most likely to undergo loss of structure and resemble free unstructured peptides against which antibodies could be generated and screened. Antibodies directed against these misfolding-prone regions, termed disease-specific epitopes (DSEs), are therefore expected to recognize cancer cells while sparing natively folded proteins on healthy cells. We have applied this strategy to develop an antibody that is specific for ovarian cancer cells, which does not bind to normal ovarian epithelium. Using the ProMIS™ computational algorithm to predict unstable regions in proteins, three DSEs in the prion protein (PrP) were identified. Ultra-high sensitivity antibodies are required for binding to isolated misfolded protein molecules at the cell surface, and thus rabbits were immunized with peptides corresponding to the PrP DSE sequences and rabbit monoclonal anti-peptide antibodies were generated. One antibody, AMF-1c-120, has sub-nanomolar binding affinity for denatured PrP, but does not bind to native PrP. AMF-1c-120 binds to four ovarian tumor cell lines and one ovarian tumor implanted and propagated in mice, but does not bind to normal ovarian epithelial cells. Proteinase K sensitivity of the AMF-1c-120 epitope is consistent with partial denaturation of PrP at the cell surface of ovarian cancer cell lines. Preclinical efficacy studies are in progress to investigate the anti-tumor effects of AMF-1c-120.

Citation Format: Marni D. Uger, Viengthong Chai, Veronica Ciolfi, Hui Chen, Ewa Plawinski, Tapfuma Mutukura, Andrew Sage, Ryan Demers, Leo Lau, Pierre Lee, Xiuwen Liu, Jun Guan, Yuzhuo Wang, William C. Guest, Steven S. Plotkin, Neil R. Cashman. AMF-1c-120: an antibody specific for misfolded prion protein expressed on ovarian cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4636. doi:10.1158/1538-7445.AM2013-4636
Abstract 464: Tumor derived vacuolar ATPase subunit promotes M2 type polarization of macrophages.
Authors: Katara Gajendra K. , Jaiswal Mukesh K. , Gilmam-Sacks Alice , Beaman Kenneth D.
Published: August 2014

Tumors and tumor associated macrophages (TAMs) express a unique surface vacuolar ATPase (V-ATPase) on the plasma membrane. In tumor cells, a 20 kd peptide is cleaved from a2 isoform of V-ATPase and is referred to as a2NTD; it is associated with in vitro induction of pro-tumorigenic properties in monocytes and IL-β secretion. In this study, we evaluated the immuno-modulatory properties of a2NTD in inducing murine peritoneal macrophage polarization and activation of inflammasome components both ex vivo and in vivo. Peritoneal macrophages from BALB/c mice were stimulated with recombinant a2NTD and the mRNA and protein expression of M1 (CD11c, TNF-α), M2 (Mannose receptor-1, Arginase-1, IL-10) markers, IL-1β and NLRP3 (inflammasome marker) were analyzed using quantitative real time PCR and flow cytometry. Further, mice were injected with a2NTD i.p. and peritoneal cells were analyzed for M1/M2 specific markers. The results of both in vivo and ex vivo analysis showed an elevated population of M2 subtype in a2NTD-treated mice compared to control (P<0.05). a2NTD upregulated the expression of IL-1β and NLRP3 in macrophages. These data demonstrated that a2NTD modulates macrophage polarization towards the M2 subtype functionally similar to tumor associated macrophages (TAMs). Since, tumor progression requires sterile inflammation and maturation of resident macrophages into TAMs; our data provide evidence that the surface expression of V-ATPase in tumor cells has a role in inducing the unique inflammatory environment of tumors by modulating macrophage phenotype and inducing IL-1β production through the action of a2NTD. The study also provides indication for the involvement of a2NTD in NLRP3 mediated inflammasome activation.

Citation Format: Gajendra K. Katara, Mukesh K. Jaiswal, Alice Gilmam-Sacks, Kenneth D. Beaman. Tumor derived vacuolar ATPase subunit promotes M2 type polarization of macrophages. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 464. doi:10.1158/1538-7445.AM2013-464
Abstract 4657: MET amplification as a potential therapeutic target in gastric cancer.
Authors: Kawakami Hisato , Okamoto Isamu , Arao Tokuzo , Okamoto Wataru , Matsumoto Kazuko , Taniguchi Hirokazu , Kuwata Kiyoko , Yamaguchi Haruka , Nishio Kazuto , Nakagawa Kazuhiko , Yamada Yasuhide
Published: August 2014

Purpose

Our aim was to investigate both the prevalence of MET amplification in gastric cancer as well as the potential of this genetic alteration to serve as a therapeutic target in gastric cancer.

Experimental Design

MET amplification was assessed by initial screening with a PCR-based copy number assay followed by confirmatory FISH analysis in formalin-fixed, paraffin-embedded specimens of gastric cancer obtained at surgery. The effects of MET tyrosine kinase inhibitors (MET-TKIs) in gastric cancer cells with or without MET amplification were also examined.

Results

The median MET copy number in 266 cases of gastric cancer was 1.7, with a range of 0.41 to 21.3. We performed FISH analysis for the 15 cases with the highest MET copy numbers. MET amplification was confirmed in the four assessable cases with a MET copy number of at least 4, whereas MET amplification was not detected in those with a gene copy number of <4. The prevalence of MET amplification was thus 1.5% (4 out of 266 cases). Inhibition of MET by MET-TKIs resulted in the induction of apoptosis accompanied by attenuation of downstream MET signaling in gastric cancer cell lines with MET amplification but not in those without this genetic change.

Conclusion

MET amplification identifies a small but clinically important subgroup of gastric cancer patients who are likely to respond to MET-TKIs. Furthermore, screening with a PCR-based copy number assay is an efficient way to reduce the number of patients requiring confirmation of MET amplification by FISH analysis.

Citation Format: Hisato Kawakami, Isamu Okamoto, Tokuzo Arao, Wataru Okamoto, Kazuko Matsumoto, Hirokazu Taniguchi, Kiyoko Kuwata, Haruka Yamaguchi, Kazuto Nishio, Kazuhiko Nakagawa, Yasuhide Yamada. MET amplification as a potential therapeutic target in gastric cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4657. doi:10.1158/1538-7445.AM2013-4657
Abstract 4695: Predictive role of FDG PET-CT in monitoring locally advanced rectal cancer (LARC) during preoperative radiochemotherapy with an experimental bevacizumab schedule.
Authors: Avallone Antonio , Delrio Paolo , Pecori Biagio , Tatangelo Fabiana , Di Gennaro Elena , Petrillo Antonella , Iaffaioli Vincenzo Rosario , Leone Alessandra , caracò Corradina , Budillon Alfredo , Lastoria Secondo , Aloj Luigi
Published: August 2014

Objectives : We have shown that pathological regression of LARC and relapse free survival can be predicted by early changes in FDG uptake during preoperative radiochemotherapy. We have attempted to improve efficacy of our neo-adjuvant treatment by adding an experimental bevacizumab (BEV) schedule. FDG PETCT was utilized to monitor response and correlate with pathological outcome.

Methods : Forty six patients with poor prognosis LARC received 3 biweekly courses of oxaliplatin/ raltitrexed (day 1) and FU/ folinic acid (day 2) during pelvic RT (45 Gy). BEV (5 mg/kg) was administered on day -4 for the first 2 courses. PET-CT was performed at baseline, on day 12 and prior to surgery and lesion TLG (mean SUV x volume) values determined. Pathologic response was defined using a modified Mandard tumor regression grade (TRG) scale. Responders were defined as TRG1-2, non-responders as TRG3-4.

Results : Thirty-seven patients (80%) showed pathologic response (65% with previous scheme). Eight patients (17%, previously 35%) were non-responders. Responders showed significantly higher TLG reduction on day 12 PET-CT (median -72% range -90%+31%) compared to non-responders (TRG3-4, median -38%, range -45% +25%, p < 0.05), confirming previous findings. Preoperative PET-CT studies, on the other hand, were not predictive of pathologic response (responders TLG change median -92%, range -100% +4%, non-responders median 86%, range -94%-76%, p = ns). Ongoing studies to define a correlation between FDG uptake and biomarkers of angiogenesis such as Circulating endothelial cells (CEC) will be presented.

Conclusions : Our findings indicate that the current scheme significantly increases pathologic response. PET-CT confirms to be a powerful early surrogate marker of treatment efficacy. PET-CT may be used to tailor more aggressive treatment for non-responsive patient

Citation Format: Antonio Avallone, Paolo Delrio, Biagio Pecori, Fabiana Tatangelo, Elena Di Gennaro, Antonella Petrillo, Vincenzo Rosario Iaffaioli, Alessandra Leone, Corradina caracò, Alfredo Budillon, Secondo Lastoria, Luigi Aloj. Predictive role of FDG PET-CT in monitoring locally advanced rectal cancer (LARC) during preoperative radiochemotherapy with an experimental bevacizumab schedule. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4695. doi:10.1158/1538-7445.AM2013-4695
Abstract 4709: EGFR inhibition augments anti-tumor immune responses by HER family-specific human CD4 helper T cells in vitro.
Authors: Kumai Takumi , Harabuchi Yasuaki , Kobayashi Hiroya
Published: August 2014

Despite immunotherapy is a promising approach for cancer treatment, there are many obstacles remain to be overcome. The characteristics of tumor evasion of immune surveillance are produced by decreased expression of immune molecules and secretion of immunoregulatory cytokines. To break these tumor microenvironment which act as suppressor of antitumor immunology, we evaluated the value of EGFR inhibitors as immune-modulators. Following two days EGFR tyrosine kinase inhibitor treatment, expression of HLA-DR molecule of head and neck squamous cancer (HNSCC) cell lines were increased, meanwhile EGFR blocking antibody treatment augmented HLA-DR expression. Furthermore, EGFR inhibitors decreased spontaneous secretion of IL-8 and TGF-β from HNSCC cell lines. To confirm the immune supporting activity of EGFR inhibitors, tumor antigen specific CD4 helper T lymphocyte (HTL) responses to EGFR-expressing tumor were investigated. We identified novel EGFR HTL epitope using MHC class II binding algorithms. The candidate EGFR peptide elicited HTL responses against EGFR-expressing HNSCC in vitro. The EGFR peptide shares high homology to HER2, HER-3 and c-Met, so that these were able to stimulate EGFR peptide reactive HTLs responses in a HLA-DR restricted manner indicating that the EGFR peptide serves a universal tumor-associated peptide in HER family and c-Met. Finally, we evaluated EGFR reactive HTL responses against HNSCC cell lines treated with EGFR inhibitors. As a result, EGFR inhibitors drastically increased HTL IFN-γ production and cytotoxic response. Since HER family and c-MET have been considered as targets of alternative pathway of EGFR inhibition, therapeutic strategy combining EGFR inhibitors with novel HTL epitope identified in this study might be attractive option for antitumor immunotherapy.

Citation Format: Takumi Kumai, Yasuaki Harabuchi, Hiroya Kobayashi. EGFR inhibition augments anti-tumor immune responses by HER family-specific human CD4 helper T cells in vitro. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4709. doi:10.1158/1538-7445.AM2013-4709
Abstract 4712: Chemotherapy-enhanced NFkB pathway activation in gynecological cancers increases the differentiation of monocytes to M2 macrophages instead of dendritic cells.
Authors: Van Der Burg Sjoerd H. , Dijkgraaf Eveline M. , Welters Marij J.P. , Kroep Judith R.
Published: August 2014

Current therapy of gynecological malignancies consists of platinum-containing chemotherapy. Resistance to therapy is associated with increased levels of interleukin-6 (IL-6) and prostaglandin E2 (PGE2), two inflammatory mediators known to skew differentiation of monocytes to tumor-promoting M2 macrophages. We investigated the impact of cisplatin and carboplatin on 10 different cervical and ovarian cancer cell lines as well as on the differentiation and function of monocytes cultured in the presence of these tumor cells in vitro. Treatment with cisplatin or carboplatin increased the potency of tumor cell lines to induce IL10-producing M2 macrophages which displayed increased levels of activated signal transducer and activator of transcription-3 (STAT3) due to tumor-produced IL-6 as well as decreased levels of activated STAT1 and STAT6 related to the PGE2-production of tumor cells. Blockade of canonical NFκB signaling showed that the effect of chemotherapy depended on the enhanced activation of the NFκB pathway and subsequent increased production of PGE2 and IL-6 by tumor cell lines originally producing these factors. Treatment with cyclooxygenase (COX)-inhibitor indomethacin and/or the clinical monoclonal antibody against IL-6 receptor (IL-6R), tocilizumab, prevented M2-differentiation. Importantly, no correlation existed between the production of PGE2 or IL-6 by cancer cells and their resistance to chemotherapy induced death, indicating that other mechanisms underlie the reported chemoresistance of tumors producing these factors. Our data suggests that a chemotherapy-mediated increase in tumor-promoting M2 macrophages may form an indirect mechanism for chemoresistance. Hence, concomitant therapy with COX-inhibitors and/or IL-6R antibodies might increase the clinical effect of platinum-based chemotherapy in otherwise resistant tumors.

Citation Format: Sjoerd H. Van Der Burg, Eveline M. Dijkgraaf, Marij J.P. Welters, Judith R. Kroep. Chemotherapy-enhanced NFkB pathway activation in gynecological cancers increases the differentiation of monocytes to M2 macrophages instead of dendritic cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4712. doi:10.1158/1538-7445.AM2013-4712
Abstract 4726: Phagocytic regulation through exogenous caffeine exposure in whole-blood macrophages.
Authors: Steck Ryan , Gustafsson Marcus , Liu PingGuo , Elnaggar Atif , Robison Richard A. , O'Neill Kim L.
Published: August 2014

Caffeine is the most widely used neurostimulant in the world, and it has been shown that 79% of the United States population drinks coffee at least occasionally. Previous research has suggested that caffeine may be involved in the regulation of phagocytosis in immune cells through anti-inflammatory and pro-inflammatory signals. To investigate this effect, we used a macrophage engulfment assay, which was optimized in our lab to measure phagocytosis after exogenous caffeine exposure. Human leukocytes were isolated and incubated to allow for monocyte differentiation. After being allowed to differentiate for 1hr, 24hrs, 3-days, or 7-days, macrophages were incubated with varying concentrations of caffeine (35 μM-20 mM) for 1-24 hours. Cells were treated with lipopolysaccharide, and then incubated for 2 hours with fluorescently-labeled microspheres conditioned by incubation with fetal bovine serum. Engulfment was measured using flow cytometry, indicating the phagocytosis of microspheres in integral ratios. It was observed that engulfment was dependent on cell differentiation time, as well as caffeine concentration and exposure time. After <12 hour differentiation, cells exposed to caffeine showed a concentration-dependent reduction in engulfment when compared to those that were not treated. During incubation for 12 - 72 hours, however, results showed a 20% down-regulation of engulfment at <5 mM caffeine, whereas those cells exposed to 5-10 mM caffeine exhibited a 20% higher-engulfing phenotype, compared to the controls. At caffeine concentrations above 10 mM cell viability and engulfment was decreased up to 50%. It was concluded that the effect of caffeine on macrophages is dependent on incubation time and concentration, as well as the state of macrophage differentiation. Because of the implications of macrophage phenotype in many diseases involving inflammation, including cancer, these findings suggest further research should be continued to explore the therapeutic potential of caffeine and/or its analogs.

Citation Format: Ryan Steck, Marcus Gustafsson, PingGuo Liu, Atif Elnaggar, Richard A. Robison, Kim L. O'Neill. Phagocytic regulation through exogenous caffeine exposure in whole-blood macrophages. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4726. doi:10.1158/1538-7445.AM2013-4726
Abstract 4777: Cytomegalovirus infection leads to pleomorphic rhabdomyosarcomas in Trp53 +/- mice.
Authors: Price Richard L. , Bingmer Katherine , Harkins Lualhati , Iwenofu Hans , Kwon Chang-Hyuk , Cook Charles , Pelloski Christopher , Chiocca E Antonio
Published: August 2014

Despite not being considered oncogenic, cytomegalovirus (CMV) has been detected in an increasing number of malignancies. However, recent studies have suggested mechanisms through which CMV may modulate the tumor environment, encouraging its study as a positive modifier of tumorigenesis. In this study, we investigated the effects of CMV infection in Trp53 heterozygous mice. Animals were infected with murine CMV (MCMV) after birth at 2 days (P2) or 4 weeks of age via intraperitoneal injection and then monitored for tumor formation. Additional control cohorts were mock-infected (saline vehicle) or infected with HSV-1, a similar herpes virus. Following MCMV infection, widespread systemic infection ensued followed by immune clearance of the virus resulting in seroconversion. Mice infected at P2 developed tumors at a high frequency (43%) by 9 months of age. In contrast, only 3% of mock-infected or mice infected at 4 weeks developed tumors. The majority of tumors from P2 MCMV-infected mice were pleomorphic rhabdomyosarcomas (RMS) as evidenced by MyoD1, Desmin, and Myogenin staining. Importantly, MCMV-infected tumors contained MCMV DNA, RNA, and protein. An examination of clinical cases revealed that human RMS (embryonal, alveolar, and pleomorphic) harbored human CMV IE1 and pp65 protein as well as viral RNA. All of the cases (n=18) tested positive for CMV genetic material. CMV protein was found throughout the tumor including pleomorphic cells. Additionally, perivascular areas demonstrated intense staining consistent with other reports of linking CMV with angiogenesis. To confirm the selective presence of HCMV DNA in human RMS, quantitative PCR analysis showed that tumors expressed an average of 81.1 copies/ng of HCMV-UL83 and of 22.2 copies/ng of HCMV-UL146 compared to 0 and 0.49 copies/ng in normal muscle, respectively. The amplified products’ nucleotide sequence was greater than 95% identical to that of a clinical strain Taken together, our findings offer support for the hypothesis that CMV contributes to the development of pleomorphic RMS in the context of Trp53 mutation, a situation which occurs with high frequency in human RMS.

Citation Format: Richard L. Price, Katherine Bingmer, Lualhati Harkins, Hans Iwenofu, Chang-Hyuk Kwon, Charles Cook, Christopher Pelloski, E Antonio Chiocca. Cytomegalovirus infection leads to pleomorphic rhabdomyosarcomas in Trp53 +/- mice. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4777. doi:10.1158/1538-7445.AM2013-4777
Abstract 4779: HERV-K env plays important roles in cell proliferation, migration and tumor progression in melanoma.
Authors: Li Ming , Johanning Gary L. , Wang-Johanning Feng
Published: August 2014

Human endogenous retroviruses (HERVs) are remnants from ancient retroviral infections, and most of them are inactive in normal tissues. However, one family of HERV, HERV-K, is reportedly active in several cancers, including melanoma. Increased expression of HERV-K in melanoma cells correlates with malignant transformation, while a serological response to HERV-K in melanoma patients correlates with survival probability. The mechanism behind these observations remains obscure. Our group reported that anti-HEEV-K envelope (env) protein antibodies shows antitumor potential in targeting breast tumors, indicating that HERV-K env may play an important role in tumorigenesis. In this study, we produced a cell line derived from melanoma cell line A375, in which the expression of HERV-K env was stably knocked down by a lentivector based shRNA. Compared to the control cells, these cells exhibit lower proliferation/migration/invasion rates and lower tumorigenicity in vitro. In vivo, their tumorigenic potential was found to be reduced after inoculation into NOD/SCID gamma mice. Moreover, results of antibody array, RNAseq and Western blotting indicate that altered HERV-K env expression led to changes in expression of several proteins important in oncogenesis and metastasis. These results suggest that HERV-K env plays specific and important roles in melanoma carcinogenesis.

Citation Format: Ming Li, Gary L. Johanning, Feng Wang-Johanning. HERV-K env plays important roles in cell proliferation, migration and tumor progression in melanoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4779. doi:10.1158/1538-7445.AM2013-4779
Abstract 4819: Assessing the environmental factors in two Ontario communities with diverging colorectal cancer incidence rates .
Authors: Sritharan Jeavana , Kamaleswaran Rishikesan , McFarlan Ken , Lemonde Manon , George Clemon , Sanchez Otto
Published: August 2014

Colorectal cancer is the third most diagnosed cancer and second leading cause of cancer related deaths in Canada. As Ontario has the largest population in Canada, it also has great disparities in colorectal cancer incidence. The region of Timiskaming has the highest incidence for colorectal cancer, while the region of Peel has the lowest incidence for colorectal cancer in Ontario. There are no previously published studies regarding cancer or environmental risk factors performed in the Timiskaming region. The purpose of this study was to identify the dominant non-nutritional modifiable environmental risk factors in the region of Timiskaming compared to the reference region of Peel that may be associated with diverging colorectal cancer incidence rates. After reviewing the available published literature, a questionnaire assessment tool regarding environmental exposures was created. This questionnaire tool was created by combining standardized questionnaire tools available in the published literature that assessed environmental exposures. The questionnaire assessment tool was then utilized within a pilot study group followed by the Timiskaming and Peel participant communities. The tool assessed the exposures of tobacco smoking, alcohol use, pesticides/organochlorines, metal toxins, occupational exposures, and medical ionizing radiation. A total of 53 participants completed the questionnaire tool in Timiskaming, and a total of 61 participants completed the questionnaire tool in Peel. Findings indicate that there are dominant non-nutritional modifiable environmental risk factors in the region of Timiskaming that may be associated with colorectal cancer when compared to the region of Peel. The significant dominant environmental factors identified by Timiskaming participants were tobacco smoking, alcohol use, pesticides/organochlorines, and metal toxins. The findings also indicate that the Peel community may have important community health initiatives that can be used in the Timiskaming community to reduce the present colorectal cancer disparities. Following this study, it is imperative that recommendations are directed at a community level and relate to the assessment of potential non-nutritional modifiable environmental risk factors. While colorectal cancer disparities are evident, future research should help to understand the relationship between cancer disparities and environmental risk factors.

Citation Format: Jeavana Sritharan, Rishikesan Kamaleswaran, Ken McFarlan, Manon Lemonde, Clemon George, Otto Sanchez. Assessing the environmental factors in two Ontario communities with diverging colorectal cancer incidence rates . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4819. doi:10.1158/1538-7445.AM2013-4819
Abstract 4821: Plasma retinol, but not 25-OH vitamin D or vitamin E, is associated with increased survival in colorectal cancer patients.
Authors: Cooney Robert V. , Chai Weiwen , Franke Adrian A. , Caberto Christian , Wilkens Lynne R. , Kolonel Laurence N. , Custer Laurie , Morrison Cynthia , Le Marchand Loic
Published: August 2014

OBJECTIVE: To determine the association of lipid-soluble vitamin status with survival in colorectal cancer patients.

METHODS: Using stored patient plasma samples from a multiethnic population-based case-control study of colorectal cancer, we determined associations of post-treatment blood levels of retinol, 25 OH-vitamin D, and Vitamin E with survival. Patients (n = 455) were followed (mean of 8 years) after phlebotomy, during which time 20% died of colorectal cancer and 24% from other causes. Hazard ratios (HR) were estimated by Cox proportional hazards regression with adjustment for stage and age at diagnosis, ethnicity, sex, and smoking status.

RESULTS: A strong inverse association with all-cause mortality was observed for plasma retinol (Ptrend <0.0001), with similar significant trends observed for both colorectal cancer-specific deaths and other causes of death (P for heterogeneity = 0.43). The inverse association between retinol and all cause mortality was consistently observed for both sexes, subjects of Caucasian and Japanese ancestry, and for both rectal cancer and colon cancer. Overall no significant associations were observed for plasma 25-OH vitamin D or vitamin E with survival.

CONCLUSIONS: Results are consistent with a direct relationship between low vitamin A status and poor survival among colorectal cancer patients. The absence of a significant association for 25-OH vitamin D levels with survival may be related to the generally higher circulating levels of 25-OH vitamin D in residents of Hawaii where the study was conducted, and results may differ in northern climates and in darker pigmented patients. If verified through larger prospective studies, future complementary intervention trials involving the assessment of vitamin A status and supplementation of individuals with inadequate levels may be warranted.

Citation Format: Robert V. Cooney, Weiwen Chai, Adrian A. Franke, Christian Caberto, Lynne R. Wilkens, Laurence N. Kolonel, Laurie Custer, Cynthia Morrison, Loic Le Marchand. Plasma retinol, but not 25-OH vitamin D or vitamin E, is associated with increased survival in colorectal cancer patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4821. doi:10.1158/1538-7445.AM2013-4821
Abstract 484: Intratumoral injection of CpG oligonucleotides induces the differentiation and reduces the immunosuppressive activity of myeloid-derived suppressor cells.
Authors: Shirota Hidekazu , Shirota Yuko , Klinman Dennis M.
Published: August 2014

Immunostimulatory CpG oligonucleotides (ODN) activate cells that express TLR9 and have been shown to improve the host's response to tumor Ags. Unfortunately, the immunosuppressive microenvironment that surrounds many cancers inhibits Agspecific cellular responses and thus interferes with CpG-mediated immunotherapy. Myeloid-derived suppressor cells (MDSC) represent an important constituent of this immunosuppressive milieu. Large numbers of MDSC are present in and near tumor sites where they inhibit the activity of Ag-specific T and NK cells. Current studies indicate that the delivery of CpG ODN directly into the tumor bed reduces the immunosuppressive activity of monocytic (CD11b+, Ly6G-, Ly6Chigh) MDSC. Monocytic MDSC express TLR9 and respond to CpG stimulation by 1) losing their ability to suppress T cell function, 2) producing Th1 cytokines, and 3) differentiating into macrophages with tumoricidal capability. These findings provide insight into a novel mechanism by which CpG ODN contribute to tumor regression, and they support intratumoral injection as the optimal route for their delivery.

Citation Format: Hidekazu Shirota, Yuko Shirota, Dennis M. Klinman. Intratumoral injection of CpG oligonucleotides induces the differentiation and reduces the immunosuppressive activity of myeloid-derived suppressor cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 484. doi:10.1158/1538-7445.AM2013-484

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 4857: Short overall telomere length and chromosome 17p-specific telomere length in peripheral blood leukocytes are associated with increased risk of esophageal adenocarcinoma.
Authors: Chen Meng , Gu Jian , Gong Yilei , Ajani Jaffer A. , Wu Xifeng
Published: August 2014

Esophageal adenocarcinoma (EAC) is a deadly cancer. The incidence of EAC has increased dramatically in the United States in the past three decades. The biological mechanisms of EAC development are not fully understood. Telomeres are specialized chromatin structures essential for the maintenance of chromosomal integrity. Telomere shortening in somatic tissues has been shown as an early event during carcinogenesis. Previous studies also suggested that constitutive short telomeres in peripheral blood leukocytes (PBLs) are associated with increased risks of several cancers, including esophageal cancer. In this study, we measured overall telomere length in PBLs using real-time PCR in a large case control study of 805 EAC cases and 805 age and gender-matched controls. Furthermore, we developed a fluorescence in site hybridization (FISH) based method to evaluate several chromosome-specific telomere length with the risk of EAC in a subset of subjects. The mean overall telomere length in cases was significantly shorter than that in controls (p<0.001). Dichotomized at the median telomere length in controls, individuals with short PBL telomere length was associated with a 1.53-fold (95% CI, 1.26-1.87) increased risk of EAC. There was a significant dose-effect in quartile analysis: Individuals in quartile with the shortest telomeres showed a nearly 2-fold (95%CI: 1.47-2.57) elevated EAC risk compared to the reference group of the longest quartile of telomere length. In chromosome-specific telomere length analysis, we found that short chromosome 17p-specific telomere length (defined as the ratio of chromosome 17p-specific telomere length to overall telomere length), but not 2p- and 7q-specific telomere length, was associated with a significantly increased risk of EAC (OR=2.02, 95% CI, 1.00-4.08). This study validates that short overall telomere length in PBLs predisposes to EAC with a much larger sample size and supports the role of chromosome 17p aberrations in EAC development.

Citation Format: Meng Chen, Jian Gu, Yilei Gong, Jaffer A. Ajani, Xifeng Wu. Short overall telomere length and chromosome 17p-specific telomere length in peripheral blood leukocytes are associated with increased risk of esophageal adenocarcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4857. doi:10.1158/1538-7445.AM2013-4857
Abstract 4858: Mutant p53 depletion: a possible mechanism of inhibition of human prostate cancer by dietary phenethyl isothiocyanate.
Authors: Mi Lixin , Wang Thomas T.Y. , Huang Haiqiu , Fletcher Arnetta , Yu Lu , Wang Xiantao , Chung Fung-Lung
Published: August 2014

Phenethyl isothiocyanate (PEITC) derived from cruciferous vegetables has been shown to inhibit tumor growth by induction of apoptosis. Previously, we demonstrated that PEITC can selectively deplete mutant p53, but not the wild type. However, whether p53, wild type or mutant, plays functional roles in PEITC-induced growth inhibition, remains unsettled. We hypothesize that the direct binding to mutant p53 by PEITC followed by conformational changes, subsequently leading to its depletion or/and restoration to the wild type may constitute a mechanism by which PEITC induces apoptosis. To determine whether PEITC can deplete mutant p53 in vivo and whether its depletion is correlated with tumor inhibition and apoptosis, in this xenograft model study BALB-C Nu/Nu mice carrying prostate tumor cells with either mutant (DU145) or wild type p53 (LNCap) were fed diets with and without PEITC (5 micromol per gram diet) for 8 weeks. Tumors were harvested at the end of bioassay for immunohistochemistry and immunoblot studies. Results showed that the tumor volumes of both LNCap and DU145 were significantly decreased in the PEITC-treated animals, compared with that on a diet without PEITC. The p53 level detected by immunoblot showed a moderate, yet significant, decrease in DU145 tumors, but not in LNCap tumors. Immunohistochemistry assays were carried out to examine the apoptotic markers, such as TUNEL, and anti-proliferation marker Ki67 in tumors from the PEITC-treated vs. untreated mice. This study provides the first in vivo evidence that mutant p53 can be depleted in tumors of mice fed PEITC-containing diet and its depletion seems to correlate with growth inhibition in the mutant p53 tumors. These findings suggest that mutant p53 maybe further investigated as a possible novel target for cancer chemoprevention and therapy by PEITC. (Supported by NCI grant CA100853)

Citation Format: Lixin Mi, Thomas T.Y. Wang, Haiqiu Huang, Arnetta Fletcher, Lu Yu, Xiantao Wang, Fung-Lung Chung. Mutant p53 depletion: a possible mechanism of inhibition of human prostate cancer by dietary phenethyl isothiocyanate. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4858. doi:10.1158/1538-7445.AM2013-4858
Abstract 4861: Identification of novel potential targets for selenomethionine-mediated chemoprevention in colorectal carcinoma mouse model via proteomics analysis.
Authors: Rahman Md. Mujibur , Kwon Jee Young , Seo Young Rok
Published: August 2014

Despite some controversy, selenomethionine (SeMet) mediated protection against colorectal carcinoma (CRC) might be a very promising non-cytotoxic option. However, responsive molecular targets and underlying mechanisms of SeMet mediated chemoprevention are still unclear. Our aim was to discover new targets of SeMet mediated chemoprevention in CRC using proteomics analysis. We found dietary SeMet supplementation before carcinoma initiation effectively suppressed polyp incidence and dysplastic lesions without any adverse effects. To determine chemopreventive targets of SeMet, we employed 2-dimensional gel electrophoresis based proteomics analysis in CRC mouse model. Pretreatment with SeMet apparently modulated the expression of 30 proteins with functions in major processes like chronic inflammation, oxidative-stress and apoptosis as discovered through pathway analysis with Pathway studio software.We validated four proteins selected from pathway analysis including prohibitin, purine nucleoside phosphorylase, annexin 2 and c-reactive protein by immuno-histochemistry. 8-hydroxy-2′-deoxyguanosine (8-OHdG), a known oxidative stress marker was decreased by SeMet treatment in CRC mice as seen by immunohistochemistry. Further network analysis was done among these new four validated proteins, 8-OHdG and colorectal cancer. These four proteins found by proteomics analysis might be considered as potential chemopreventive biomarkers of SeMet against colon cancer and can help develop and improve approaches in preventive, therapeutic and prognostic aspects.

Citation Format: Md. Mujibur Rahman, Jee Young Kwon, Young Rok Seo. Identification of novel potential targets for selenomethionine-mediated chemoprevention in colorectal carcinoma mouse model via proteomics analysis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4861. doi:10.1158/1538-7445.AM2013-4861