bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5155: Integrated genomic analysis of colorectal cancer progression reveals activation of EGFR through demethylation of the EREG promoter
Authors: Qu Xueping , Sandmann Thomas , Frierson Henry , Fu Ling , Fuentes Eloisa , Walter Kimberly , Okrah Kwame , Rumpel Craig , Moskaluk Christopher , Lu Shan , Wang Yulei , Bourgon Richard , Penuel Elicia , Pirzkall Andrea , Amler Lukas , Lackner Mark , Tabenero Josep , Hampton Garret , Kabbarah Omar
Published: July 2016

The molecular drivers that underlie transformation of colonic epithelium into colorectal adenocarcinoma (CRC) have been well described. However, the mechanisms through which some of the clinically targeted pathways are activated during CRC progression have yet to be elucidated. Here, we employed an integrative genomics approach to examine CRC progression. Transcriptional profiling of laser capture microdissected colonic crypt cells, differentiated surface epithelium, adenomas, carcinomas, and metastases, showed distinctive patterns in the activation of developmental and oncogenic pathways, including the clinically important EGFR axis. We observed a dramatic up-regulation of the EGFR ligand EREG in primary and metastatic cancer cells as compared to normal and adenomatous tissues that was indicative of autocrine tumor production, and confirmed this pattern of gene expression by in situ hybridization. Global methylation analysis indicated that up-regulation of EREG during the adenoma-carcinoma transition was associated with de-methylation of two key sites within the EREG promoter and this was accompanied by an increase in the levels of EGFR phosphorylation, as assessed by reverse phase protein analysis. In a clinical trial setting, we observed that low levels of EREG methylation in patients who received cetuximab as part of a Phase II study were associated with high expression of the ligand and a favorable response to therapy. Conversely, high levels of promoter methylation and low levels of EREG expression were observed in tumors that progressed after treatment. We also noted an inverse correlation between EREG methylation and expression levels in several other cancers from the TCGA datasets, including those of the head and neck, lung, and bladder. We propose that up-regulation of EREG expression through promoter de-methylation might be an important means of activating the EGFR pathway during the genesis of CRC and, potentially, other types of cancer.

Citation Format: Xueping Qu, Thomas Sandmann, Henry Frierson, Ling Fu, Eloisa Fuentes, Kimberly Walter, Kwame Okrah, Craig Rumpel, Christopher Moskaluk, Shan Lu, Yulei Wang, Richard Bourgon, Elicia Penuel, Andrea Pirzkall, Lukas Amler, Mark Lackner, Josep Tabenero, Garret Hampton, Omar Kabbarah. Integrated genomic analysis of colorectal cancer progression reveals activation of EGFR through demethylation of the EREG promoter. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5155.
Abstract 5157: Quantitative proteomic analysis identifying Krt17 plays a critical role in areca nut inducing oral carcinogenesis
Authors: Chiang Chang Hsu , Wu Chih-Ching , Cheng Ann-Joy
Published: July 2016

Areca nut is known a carcinogen for oral cancer in southeast Asia, however, the molecular mechanism leading to the malignancy is still unclear. To mimic the habit of areca nut chewing, our laboratory has established four oral cancer cell sublines (SAS, OECM1, K2, C9), chronically trained by areca nut extract (ANE). To elucidate the molecular basis of areca nut induced oral carcinogenesis, the differential proteomes between oral cancer cells and the ANE sublines were determined using the technique of isobaric mass tag (iTRAQ) labeling and multidimensional liquid chromatography- mass spectrometry (LC-MS/MS). Over thousand proteins were identified in four sublines, in which 194 proteins were found differential expressions in at least two ANE sublines. Bioinforatmic analysis revealed that these proteins participate in several pathways, with the regulation of epithelial to mesenchymal transition (EMT) most prominent. Fourteen proteins were confirmed differential expression in the ANE sublines, including Krt17. To shed more light on the mechanism of ANE induced carcinogenesis, Krt17 was further investigated. Knockdown Krt17 significantly suppressed ANE-induced cell growth, migration, and cell invasion, along with the modulation of EMT process. Furthermore, in a carcinogen-induced oral cancer mice model by 4NQO/arecoline, an active compound of ANE, Krt17 was found significantly up-regulated in all hyperplasia and carcinoma (p<0.001). In conclusion, we have identified proteome associated with chronic areca nut exposure in oral cancer cells. Krt17 was demonstrated contributing to areca nut induced oral malignancy. This study should attribute to risk assessment, disease prevention or other clinical applications of areca nut-induced oral cancer.

Citation Format: Chang Hsu Chiang, Chih-Ching Wu, Ann-Joy Cheng. Quantitative proteomic analysis identifying Krt17 plays a critical role in areca nut inducing oral carcinogenesis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5157.
Abstract 5174: Modeling mesothelioma initiation through disruption of the Hippo pathway revealed involvement of PLCB4 in YAP-driven mesothelioma cell proliferation
Authors: kakiuchi. tatsuo
Published: July 2016

Disruption of the Hippo pathway as a result of deletion and/or mutation of the involved genes (e.g., neurofibromin 2 [NF2]) is frequently observed in mesothelioma. The disruption results in reduced phosphorylation of yes-associated protein (YAP), and the non-phosphorylated YAP translocates to the nucleus and regulates gene expression. While the roles of the disrupted Hippo pathway in the maintenance of established tumors have been investigated using mesothelioma cell lines, its involvement in the initiation of mesothelioma remains unclear.

We used immortalized human mesothelial cells to study the transformation process, and found that NF2 knockdown led to transformation of the cells concurrently with reduction in YAP phosphorylation. The cells exhibited enhanced growth in vitro, and formed tumors following transplantation into nude mice. Similar results to those obtained by NF2 knockdown were also obtained using enforced expression of wild-type (wt) or constitutively active (S127A) YAP. Although enforced expression of YAPwt or YAPS127A was insufficient to transform primary (unimmortalized) human mesothelial cells, our findings provide evidence for the crucial roles of activated YAP in the transformation of mesothelial cells.

To identify YAP-regulated genes critical for mesothelial tumorigenesis, we conducted gene expression analysis comparing control- and YAP-transduced immortalized human mesothelial cells. Gene Set Enrichment Analysis (GSEA) using a gene set down-regulated by YAP knock-down in mesothelioma cell lines revealed phospholipase C beta 4 (PLCB4) to be among the top-ranking genes up-regulated by YAP in our experiments. PLCB4 was up-regulated by YAP in immortalized human mesothelial cells, and down-regulated by YAP knock-down in YAP-driven mesothelioma cells. shRNA-mediated silencing of PLCB4 attenuated the growth of YAP-transduced mesothelial cells and Hippo-disrupted, but not -proficient, mesothelioma cell lines.

Our model system thus provides a versatile tool to investigate the mechanisms underlying mesothelioma development. We suggest that PLCB4 may be an attractive drug target for the treatment of malignant mesothelioma.

Citation Format: tatsuo kakiuchi. Modeling mesothelioma initiation through disruption of the Hippo pathway revealed involvement of PLCB4 in YAP-driven mesothelioma cell proliferation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5174.
Abstract 5181: Dual inhibition of RNA Pol I transcription and PIM kinase as a new therapy to treat prostate cancer
Authors: Rebello Richard J. , Kusnadi Eric , Cameron Don , Lesmana Analia , Drygin Denis , Clark Ashlee K. , Porter Laura , Sandhu Shahneen , Risbridger Gail P. , Pearson Richard B. , Hannan Ross D. , Furic Luc
Published: July 2016

Background: The MYC oncogene is commonly over-expressed in prostate cancer (PC). Upregulation of ribosome biogenesis and function is a characteristic feature of MYC-driven tumors. Accordingly, inhibition of ribosomal RNA (rRNA) synthesis with CX-5461, a potent, selective and orally bioavailable inhibitor of RNA polymerase I (Pol I) transcription has been successfully exploited therapeutically in models of hematological malignancy characterized by elevated MYC expression. Additionally, PIM kinases activate MYC signaling and mRNA translation in PC and cooperate with MYC to accelerate tumorigenesis. Here we investigate the efficacy of a dual approach targeting ribosome biogenesis and function to treat PC by combining CX-5461 with the pan-PIM kinase inhibitor CX-6258 in murine and human models

Methods: The efficacy of CX-5461 and CX-6258, alone and in combination, was tested in PC cell lines, in the Hi-MYC mouse model of PC (n = 8-11 per group) and in PC metastatic tissues. Primary cell lines derived from Hi-MYC mice were used to analyze signaling events underpinning therapeutic efficacy. Triplicate experiments were analyzed with ANOVA followed by Dunnett's post hoc test. All statistical tests were two-sided.

Results: CX-5461 reduced anchorage independent growth and induced cell cycle arrest in human PC cell lines and in primary prostatic epithelial cells from Hi-MYC mice (P<0.001). CX-5461 treatment of Hi-MYC mice induced p53 expression and activity and significantly reduced prostate epithelial cell proliferation (P = 0.02) and invasion. While CX-6258 showed little effect alone, its combination with CX-5461 further suppressed proliferation (P = 0.01), dramatically reduced the incidence of large invasive lesions from 64% to 9% and preserved prostate ductal architecture.

This promising combination strategy prevented the growth of PDX tissue characterized by elevated MYC and resistance to conventional therapy (P = 0.04).

Conclusions: Our results demonstrate preclinical efficacy of combination therapies targeting the ribosome at multiple levels and provide a new approach for treatment of PC with high MYC activity.

Citation Format: Richard J. Rebello, Eric Kusnadi, Don Cameron, Analia Lesmana, Denis Drygin, Ashlee K. Clark, Laura Porter, Shahneen Sandhu, Gail P. Risbridger, Richard B. Pearson, Ross D. Hannan, Luc Furic. Dual inhibition of RNA Pol I transcription and PIM kinase as a new therapy to treat prostate cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5181.
Abstract 5186: Using HuTrial™ to aid in predicting a patient population of responders
Authors: Thatte Jayant , Ricono Jill , Scott Colleen , Broudy Thomas B.
Published: July 2016

One of the biggest challenges in drug discovery is directing drug treatment to the correct population. Crown Bioscience currently has over 1,800 Patient derived xenograft models in >70 indications. These models, HuPrime® human surrogate mouse models, are reflective of the diversity of genetics, tumor heterogeneity and response in patient populations. HuPrime® models are searchable in the HuBase™ database by the expression data, copy number, mutational analysis as well as patient clinical data including diagnosis, pathology and IHC information. The vast number of models available allows one to perform surrogate clinical trials in a Phase II-like trial utilizing one patient sample per tumor bearing animal per treatment group (n = 1 studies). In this study we show reproducibility of n = 1 studies compared to the traditional preclinical mouse studies with multiple animals with the same tumor being treating with the same test agent. Further we show, the use of one patient sample per treatment allows for the expansion of the study utilizing multiple patient samples thereby reducing cost of preclinical studies. One can leverage the HuPrime® models to discover biomarkers, identify patient responder and non-responder profiles to accelerate drug development and improve chances of success in the clinic.

Citation Format: Jayant Thatte, Jill Ricono, Colleen Scott, Thomas B. Broudy. Using HuTrial™ to aid in predicting a patient population of responders. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5186.
Abstract 520: The role of the calpain pathway in early response and acquired resistance to radiation in glioblastoma
Authors: Bassett Emily A. , Chakravarti Arnab
Published: July 2016

Glioblastoma (GBM) is the most aggressive, malignant brain tumor that is highly heterogeneous and often develops resistance to conventional chemotherapy and radiation treatments. The median survival time of GBM patients is 12-15 months despite aggressive treatment modalities, and there is an urgent need for the development of novel treatment strategies. The goal of this study is to identify novel mechanisms of radioresistance in GBM through mass spectrometry-based phosphoproteomic profiling, with the objective that more effective therapies can be rationally developed in the future. We and others have previously reported that GBMs are characterized by deregulated signaling pathways that control critical cellular processes including survival, migration, and proliferation. Very little is known about acquired resistance mechanisms to radiation, specifically how radiation alters protein phosphorylation patterns in tumors on a global level, or how radiation-induced changes in protein phosphorylation contribute to treatment resistance. In order to identify radiation-induced changes in protein phosphorylation, we performed phosphoproteomic profiling of 6 GBM cell lines and 1 normal human astrocyte cell line both before and after radiation treatment in 3 independent experiments. Specifically, cells were collected before treatment and at 2 time-points following a 10 Gy radiation treatment. Following protein isolation and phosphopeptide enrichment, global phosphoproteomic analysis was performed by mass spectrometry. Relative quantitation and statistical analysis were performed to determine fold changes in phosphorylation at both post-radiation time-points. An average of 3,971 phosphopeptides mapping to 1,649 phosphoproteins were quantified for each independent experiment, and a total of 621 phosphoproteins were quantified across all 3 datasets. We identified a major component of the calpain signaling pathway that consistently shows an increase in phosphorylation following radiation treatment in GBM cell lines. The post-radiation increase in phosphorylation was confirmed in 2 independent experiments and observed across all 6 GBM cell lines. This is the first study linking the calpain signaling pathway to radiation response in GBM. Mechanistic studies using phosphomimetic and nonphosphorylatable mutants of the protein of interest will determine the effect of phosphorylation on calpain activity and radiation resistance. Results of this work will contribute to our understanding of how GBM tumors become resistant to radiation therapy, and may identify a novel target to overcome radiation resistance in GBM.

Citation Format: Emily A. Bassett, Arnab Chakravarti. The role of the calpain pathway in early response and acquired resistance to radiation in glioblastoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 520.
Abstract 5200: Preclinical model of patient-derived tumor xenograft in humanized mice
Authors: Wulf-Goldenberg Annika , Stecklum Maria , Fichtner Iduna , Hoffmann Jens
Published: July 2016

Human patient-derived xenografts (PDX) from different tumor indications transplanted on immunodeficient mice have demonstrated strong predictive power for many drug development programs in cancer research. However, one caveat of PDX models is that they lack a functional immune system, which allows tumor engraftment in the xenogenic host mice.

Immunotherapy has emerged as one of the most promising avenues for cancer therapy. For translating immunotherapies into the clinics preclinical animal models are needed which harbor human immune cell repertoire for rising an immune response.

To overcome these constraints our aim is the development of PDX models on mice with a functional human immune system to improve predictability of drug efficacy and safety.

We reconstituted a human immune system in mice by engrafting human hematopoietic stem cells in immunodeficient mice. We were able to demonstrate that in the mice a full set of human immune cells, including T cells, B cells, NK cells, monocytes and dendritic cells can be analyzed by flow cytometry.

At the time when the human immune system was developed, established patient-derived tumors were transplanted on these reconstituted humanized mice. PDX from different tumor entities were transplanted. The tumors are growing on these humanized mice either similar to non humanized mice or slightly slower. During the observation period no rejections by the human immune cells were evident, although tumor growth was accompanied by an increase of human T cells in the peripheral blood. Ex vivo analysis will be performed demonstrating the cytotoxicity of these T cells and the functionality of the human immune cells.

Humanized mice bearing various PDX tumors were treated with therapeutic checkpoint inhibitors. Ipilimumab that target the CTLA-4 receptor lead to a slight tumor growth delay and an increased percentage of T cells in the blood and in the tumor. Nivolumab that targets the PD-1 receptor showed similar results. The combination of both inhibitors showed a synergistic effect which lead to a greater tumor growth inhibition.

Our humanized mouse models enable appropriate preclinical assessment of immune-based therapeutic anti-tumor strategies especially when combing the humanized mouse with patient-derived tumor xenografts.

Citation Format: Annika Wulf-Goldenberg, Maria Stecklum, Iduna Fichtner, Jens Hoffmann. Preclinical model of patient-derived tumor xenograft in humanized mice. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5200.
Abstract 5211: Trends in the incidence of retinoblastoma in the United States from 1973-2012
Authors: Fernandes Arthur G. , Pollock Benjamin D. , Hoffman Aaron E.
Published: July 2016

Background: Retinoblastoma is a rare form of eye cancer that usually develops in early childhood, typically before the age of 5. This study aims to determine the incidence of retinoblastoma in the United States over a 40-year period from 1973 to 2012 using a review of existing databases.

Methods: 882 patients with retinoblastoma (International Classification of Diseases for Oncology (ICD-O-3) codes C69.2 (retina) and C69.9 (eye, NOS)) were derived from the Surveillance, Epidemiology, and End Results (SEER) program database in the United States from 1973 to 2012, using the nine historical SEER registries with the earliest observation collections. Incidence rates were calculated per 1,000,000 children and age-adjusted using the United States Census Bureau data as the standard population. The significance of trend in the incidence rate over time was determined using the Chi-Square test, and 95% CIs were calculated. Descriptive statistics evaluated differences in incidence in terms of age group, gender, race and laterality. Surveillance was evaluated by analysis of diagnosis confirmation and reporting source.

Results: There were a total of 882 cases of retinoblastoma, representing 6.1% of all childhood cancers under age 5 years. 49.1% of cases were males and 96% of all cases were children aged 0-4 years. The mean incidence of retinoblastoma was 12.14 cases per million children aged 0-4 years (95% CI 11.32 to 12.96) and 0.49 cases per million children aged 5-9 years (95% CI 0.36 to 0.65). There was no significant trend in the incidence for children aged 0-4 years old (Xsup2 = 35.455 p = 0.6324) or 5-9 years old (Xsup2 = 32.247 p = 0.7695) for all races/genders. The proportion of bilateral cases (28.9%) versus unilateral cases (71.1%) remained stable over the 40-year period. 85.6% of the cases were confirmed microscopically and hospitals represent 98.8% of the reporting sources.

Conclusions: The incidence rate of retinoblastoma in the United States has remained stable for the last 40 years. The majority of the cases are unilateral, and hospitals are the main reporting source.

Citation Format: Arthur G. Fernandes, Benjamin D. Pollock, Aaron E. Hoffman. Trends in the incidence of retinoblastoma in the United States from 1973-2012. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5211.
Abstract 5223: A novel molecular inversion probe (MIP) system for the streamlined identification of germline and somatic sequence variants in cancer
Authors: Jefferson Keynttisha , Halvensleben Heather , Green Dawn , Bannen Ryan , Brockman Michael , Richmond Todd , Burgess Daniel
Published: July 2016

Characterization of the somatic sequence variations that accrue in cells is critical for understanding the pronounced cellular and clinical heterogeneity observed in cancer. The ability to efficiently detect variations in tumors can help to identify biomarkers which may be relevant to clinical trials, support more accurate prognosis, and help guide more effective choices of therapy. Next-generation sequencing (NGS) has become a valuable tool for discovering somatic mutations in cancers. Here we present an alternative approach to current methodologies for addressing these needs.

HEAT-Seq (High Efficiency Amplification of Targets for Sequencing) is a targeted NGS method based on optimized, multiplexed molecular inversion probes (MIPs). This is a convenient, sensitive and cost-effective target enrichment technology for SNP discovery and SNP validation in cancer-related genes. HEAT-Seq probes target both DNA strands and were designed to facilitate bioinformatic error correction. Molecule identifiers (UIDs) incorporated into the probes tag PCR duplicates and support ultra-sensitive detection of low frequency variants, reduction of false positives, and accurate assessment of molecular complexity free of amplification bias. Sensitivities for allele detection have been measured to below 1%.

The HEAT-Seq workflow from input DNA to sequence-ready sample can be completed in ≤8 hours without any requirement for a separate library preparation step, which saves both time and cost. Additionally, the capture, amplification and sample clean up steps are performed in a single reaction tube. This eliminates the need to transfer samples to subsequent reaction tubes, preserves sample identity, prevents cross contamination, limits sample loss, and makes the HEAT-Seq protocol easy to automate. A comparison of current PCR-based targeted sequencing with the new HEAT-Seq technology indicates significant advantages for HEAT-Seq in the accurate quantification of low frequency cancer variants.

In summary, HEAT-Seq technology offers a rapid, convenient, automatable option to identify genomic DNA variants and enable advances in cancer research.

Citation Format: Keynttisha Jefferson, Heather Halvensleben, Dawn Green, Ryan Bannen, Michael Brockman, Todd Richmond, Daniel Burgess. A novel molecular inversion probe (MIP) system for the streamlined identification of germline and somatic sequence variants in cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5223.
Abstract 5237: Protection of tocopherols against estrogen-induced breast cancer via mechanisms targeting cancer stem cells
Authors: Bak Min Ji , Das Gupta Soumyasri , Wahler Joseph , Lee Mao-Jung , Lin Yong , Joe Shih Weichung , Yang Chung S , Suh Nanjoo
Published: July 2016

Estrogens have been implicated to be complete carcinogens through mechanisms involving increased proliferation, oxidative stress and DNA damage. Although the importance of estrogen in breast cancer is well established, the effects of estrogen on breast cancer stem cells are not fully understood. Due to the role of breast cancer stem cells in tumor initiation, maintenance, and progression, targeting cancer stem cells has become important for understanding estrogen-mediated breast carcinogenesis. The vitamin E family, which is consisted of four different forms of tocopherols and tocotrienols, has been shown to exert anti-tumor effects in animal models of various cancers. In the present study, we examined the protective effects of α-, γ-, δ-tocopherol as well as a natural γ-tocopherol rich mixture of tocopherols (γ-TmT) against estrogen-induced expansion of cancer stem-like cells and estrogen-mediated tumor growth. To determine the effects of tocopherols on breast cancer stem cells, the MCF-7 mammosphere cell culture system, which enriches for mammary progenitor cells and putative breast cancer stem cells, was utilized. Treatment of MCF-7 mammosphere with estrogen for six days resulted in an increase in CD44+/CD24- stem-like cell populations as well as the number and size of mammosphere. α-, γ-, δ-Tocopherol, and most significantly γ-TmT, inhibited estrogen-induced mammosphere formation, indicating that tocopherols reverse estrogen-induced expansion of breast cancer stem cells. In MCF-7 xenograft tumor study, MCF-7 cells (5 × 106 cells/mouse) were injected into the mammary fat pad in immunodeficient mice after subcutaneous implantation with 0.72 mg of estrogen pellet. Mice were then administered with diets containing 0.2% α-, γ-, δ-tocopherol and γ-TmT for 5 weeks. Treatment of α-, γ-, δ-tocopherol or γ-TmT reduced the tumor volume by 71% (p<0.05), 55% (p<0.05), 59% (p<0.05) and 42% (p<0.01) as well as tumor weight by 80%, 63% (p<0.05), 61% (p<0.05) and 48% (p<0.05), respectively. Our results suggest that tocopherols significantly repress the expansion of breast cancer stem cell-like population and tumor development. Tocopherols, in particular a naturally occurring tocopherol mixture rich in γ and δ-tocopherols, could thus be effective natural agents for the prevention and treatment of estrogen-induced breast cancer.(This work was supported by NIH R01 AT007036)

Citation Format: Min Ji Bak, Soumyasri Das Gupta, Joseph Wahler, Mao-Jung Lee, Yong Lin, Weichung Joe Shih, Chung S Yang, Nanjoo Suh. Protection of tocopherols against estrogen-induced breast cancer via mechanisms targeting cancer stem cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5237.
Abstract 5247: Caffeic acid phenethyl ester (CAPE) reverses aggressive breast cancer in the radiation chimera model
Authors: Omene Coral O. , Patel Manan , IllaBochaca Irineu , Barcellos-Hoff Mary Helen
Published: July 2016

CAPE is the major active component of propolis, a widely available, safe, honeybee natural product with anti-inflammatory, antioxidant, and antitumor properties. We have previously shown diverse effects of CAPE in breast cancer. We postulated that CAPE may be useful in chemoprevention for women at high risk for triple-negative breast cancers (TNBC) and evaluated this in a radiation chimera mouse model in which the tumor spectrum is shifted to TNBC.

The radiation chimera model consists of surgically clearing the mammary epithelium from the inguinal glands of 3-week old BALB/c mice, the mice were irradiated with 1 Gy or sham irradiated at 10-12 weeks of age, and bilaterally transplanted 3 days later with syngeneic Trp53 null mammary fragments. Mice were placed on a CAPE diet or a control diet at 1 month post transplantation that was maintained for the course of the experiment. Mammary tumor development was monitored by palpation for up to 18 months. The first tumor was resected at 1cm3 and mice monitored for tumor recurrence or second tumor formation. Tumors were immunostained for estrogen receptor (ER) status and ER negative tumors were selected from all the groups for RNA sequencing.

No difference in body weight or tumor incidence was observed between mice on the CAPE versus control diet. Host irradiation significantly accelerated tumor growth rate compared to the control sham irradiated mice. CAPE treatment blocked this effect, but did not affect the control tumor growth rate. Resected tumors in CAPE treated mice recurred at significantly longer intervals (average of 40 days in the control group versus 90 days with CAPE treatment) and much less frequently than tumors from mice on a control diet. Mean expression analysis showed that CAPE induces a distinct gene expression pattern in ER negative tumors from irradiated mice. As previously described, the transcriptional profile of ER negative tumors was enriched in immune response genes in tumors from irradiated mice on a control diet. Interestingly, this difference was abrogated in mice on the CAPE diet.

These findings support the potential use of CAPE to modify the aggressive behavior of TNBC. This may be due to effects on the immune system in which CAPE acts to re-establish anti tumor immunity. Thus, CAPE may be useful in chemoprevention both for women at high risk for TNBC and to prevent or delay TNBC breast cancer recurrence.

Citation Format: Coral O. Omene, Manan Patel, Irineu IllaBochaca, Mary Helen Barcellos-Hoff. Caffeic acid phenethyl ester (CAPE) reverses aggressive breast cancer in the radiation chimera model. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5247.
Abstract 5250: Photopreventive effect and mechanism of AZD4547 and curcumin C3 complex on UVB-induced epidermal hyperplasia
Authors: Khandelwal Alok R. , Xiaohua Rong , Moore-Medlin Tara , Ekshyyan Oleksandr , Fleurette Abreo , Gu Xin , Nathan Cherie-Ann O.
Published: July 2016

Aggressive cutaneous squamous cell carcinoma (cSCC) of the skin is the second most common type of skin cancer in the USA due to high exposure to ultraviolet-B (UVB) radiation. In our previous studies Curcumin C3 complex (C3), a standardized preparation of three curcumonoids, delayed UVB-induced tumor incidence and inhibited multiplicity. Exposure to UVB activates mTOR and FGFR signaling both of which play a key role in skin tumorigenesis. The purpose of this study was to investigate the efficacy of C3 complex to afford protection against UVB-induced hyper proliferation by targeting the mTOR and FGFR signaling pathways. Pre-treatment with C3 complex significantly inhibited UVB-induced FGF-2 induction, FGF-2-induced colony formation, mTORC1 and mTORC2 activation and FGFR2 phosphorylation in promotion sensitive JB6 epithelial cells. Further, FGFR2 was required for UVB-induced mTOR activation suggesting an important role of FGFR2 in UVB-induced mTOR signaling. SKH-1 mice pre-treated with C3 (15mg/kg/b.w) for 2 weeks followed by a single exposure to UVB (50mj/cm2) significantly attenuated UVB-induced mTOR and FGFR activation. To further assess the role of FGFR in UVB-induced hyper proliferation, SKH-1 mice were pre-treated with AZD4547; a selective pan-FGFR kinase inhibitor followed by single exposure to UVB (50mj/cm2). AZD4547 significantly inhibited UVB-induced mTORC1 and mTORC2 activation, epidermal hyperplasia and hyper proliferation. Our studies underscore the importance of FGFR signaling in UVB-induced acute skin changes and the role of FGFR/mTOR pathway in mediating the effects of C3 complex in the pathogenesis of skin cancer.

Citation Format: Alok R. Khandelwal, Rong Xiaohua, Tara Moore-Medlin, Oleksandr Ekshyyan, Abreo Fleurette, Xin Gu, Cherie-Ann O. Nathan. Photopreventive effect and mechanism of AZD4547 and curcumin C3 complex on UVB-induced epidermal hyperplasia. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5250.
Abstract 5252: Skin cancer prevention by traditional Chinese medicinal formula Si-Wu-Tang and its constituents
Authors: Huang Kevin , Liu Mandy , Zhang Suhui , Yeung Steven , Chang Andy , Qian Li , Chatterjee Payal , Li Rui , Zhou Su , Mei Nan , Wang Zhijun , Parsa Cyrus , Orlando Robert , Luo Yun , Huang Ying
Published: July 2016

Si-Wu-Tang (SWT), comprising the combination of four herbs, Rehmanniae, Angelica, Chuanxiong and Paeoniae, is one of the most popular Chinese medicines for women's diseases. Previously we showed that SWT was able to upregulate genes in the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, suggesting a potential application for cancer chemoprevention. The present study examined the chemopreventive activity of SWT using models of skin carcinogenesis. In JB6 P+ cells, a non-cancerous murine epidermal cell line for studying skin tumor promotion, SWT inhibited epidermal growth factor (EGF)-induced neoplastic transformation. In a 7,12-dimethylbenz(a)anthracene (DMBA)-induced murine skin tumorigenesis model, both topical and oral treatment of SWT inhibited epidermal hyperplasia, proliferating cell nuclear antigen expression, and H-ras mutations induced by DMBA treatment. In addition, SWT exhibited a significant antimutagenic activity against DMBA-induced mutagenicity, determined by the Ames Test using Salmonella typhimurium TA100 in the presence of metabolic activator S9 system. To identify active components in SWT, among nine compounds previously reported in commercial SWT products, in silico molecular docking analysis predicted some as potential Nrf2 activators due to an ability of interfering the forming of Nrf2-Keap1 complex. Three of these compounds, gallic acid, Z-liguistilide and senkyunolide A, were confirmed with highest potency of increasing the antioxidant response element luciferase reporter activity, inducing Nrf2-regulated genes Hmox1, Slc7A11 and Nqo1, and inhibiting EGF-induced JB6 P+ transformation. Further mechanistic studies showed that SWT and the three compounds suppressed EGF-induced activation of the activator protein 1 (AP-1), an essential transcription factor involved in skin carcinogenesis. The antimutagenic activity for the three compounds was also confirmed with the Ames Test. In conclusion, these results provide evidence that SWT and its constituents are able to prevent skin cancer, at least partly, by activating the Nrf2 pathway and blocking the activation of AP-1. Thus, this widely used Chinese medicinal formula may provide a promising option toward preventing skin cancer or may be other types of cancer.

Citation Format: Kevin Huang, Mandy Liu, Suhui Zhang, Steven Yeung, Andy Chang, Li Qian, Payal Chatterjee, Rui Li, Su Zhou, Nan Mei, Zhijun Wang, Cyrus Parsa, Robert Orlando, Yun Luo, Ying Huang. Skin cancer prevention by traditional Chinese medicinal formula Si-Wu-Tang and its constituents. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5252.
Abstract 5257: Upregulation of glutathione S-transferase P1 by green tea polyphenols: A novel transcriptional target of p53 tumor suppressor gene
Authors: Thakur Vijay S. , Deb Gauri , Jackson Mark W. , Gupta Sanjay
Published: July 2016

Green tea polyphenols (GTPs) and its major constituent (-)-epigallocatechin-3-gallate (EGCG) reactivate epigenetically silenced genes in cancer cells. Glutathione S-transferase P1 (GSTP1), an enzyme involved in detoxification process, is frequently inactivated in prostate cancer due to epigenetic modifications. The mechanisms underlying the re-expression of GSTP1 expression by GTP/EGCG in prostate cancer is currently not well understood. Earlier we demonstrated the ability of GTP/EGCG to increase p53 transcriptional activity through suppression of class I histone deacetylases (Carcinogenesis 33(2):377-84, 2012). Here we report that the GSTP1 gene is an unrecognized downstream transcriptional target of the tumor suppressor p53, and that GTP/EGCG has ability to increase GSTP1 expression mediated through p53. Treatment of human prostate cancer LNCaP cells with 5μg/ml GTP and 20μM EGCG, activate p53 through acetylation at the Lys373 and Lys382 residues along with consequent increase in GSTP1 protein expression in time-dependent manner. To study the possible interaction between GSTP1 and p53, LNCaP cells stably-transfected with short hairpin-RNA against p53 (LNCaPshp53) and control vector (LNCaPshV) for generation of p53 knockout cells. GTP/EGCG treatment induced p53 activation and acetylation at p53 Lys373 and Lys382 specifically in LNCaPshV cells in time-dependent manner, but not in LNCaPshp53. This increase in p53 acetylation led to activation of GSTP1 in LNCaPshV cells both at protein and message levels. GTP/EGCG-mediated increase in GSTP1 expression is caused by increase binding of p53 to its consensus binding site on the intron 4 of GSTP1 gene as analyzed by electrophoretic mobility shift binding assay. Furthermore, this association was validated by ChIP assay where GTP/EGCG treatment led to an increase in the amount of acetylated p53-Lys373 associated within the intron site of GSTP1, compared to untreated controls. Taken together, our findings indicate the ability of p53 to transcriptionally activate the human GSTP1 gene, which defines a novel mechanism of protection of the genome by green tea polyphenols.

Citation Format: Vijay S. Thakur, Gauri Deb, Mark W. Jackson, Sanjay Gupta. Upregulation of glutathione S-transferase P1 by green tea polyphenols: A novel transcriptional target of p53 tumor suppressor gene. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5257.
Abstract 5265: Cloud-based somatic analysis platform for populations with paired tumor normal samples
Authors: Lou Melanie , Beale Holly
Published: July 2016

Maverix Biomics introduces its cloud-based somatic analysis platform, a scientifically sound, end-to-end analysis solution that begins with quality control of fastq reads and leads to somatic variant calling, annotation and interactive analysis and has been validated using paired tumor normal cancer samples from the COSMIC cell line project (CLP). In addition to providing the ability to call somatic variants for cancer populations and features to explore characteristics within each of these populations, another strength of the Maverix Analytic Platform is the ability to compare multiple cancer populations - a limitation in other existing platforms. To support this functionality, our cloud-based platform has been optimized using the biological expectations of COSMIC CLP data and outfitted with interactive features within Maverix's Variant Explorer. Specifically, we maximized the sensitivity and minimized the percentage of unvalidated variants of two COSMIC cancer cell lines - small cell lung carcinoma and renal cell carcinoma. Then interactive analysis of this data using Maverix's Variant Explorer has identified somatic variants and affected genes specific to each cancer population and shared among both cancer populations. Our platform expedites data exploration and the ability to identify similarities and differences among cancer populations which is useful for tumor reclassification and for repurposing targeted therapies based on discovering similar genetic profiles across different types of cancer.

Citation Format: Melanie Lou, Holly Beale. Cloud-based somatic analysis platform for populations with paired tumor normal samples. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5265.
Abstract 527: Myeloid PTEN deficiency impairs tumor immune surveillance via immune checkpoint inhibition
Authors: Kuttke Mario , Sahin Emine , Pisoni Julia , Percig Sophie , Vogel Andrea , Kraemmer Daniel , Hanzl Leslie , Brunner Julia Stefanie , Paar Hannah , Soukup Klara , Halfmann Angela , Dohnal Alexander , Steiner Carl-Walter , Blüml Stephan , Basilio Jose , Hochreiter Bernhard , Salzmann Manuel , Hoesel Bastian , Lametschwandtner Günther , Eferl Robert , Schmid Johannes , Schabbauer Gernot
Published: July 2016

In the current study we are investigating the effects of PTEN-deficient myeloid cells on tumor immune surveillance. We could previously show that hyper-activation of the PI3K signaling cascade by genetic knock-out of the counteracting phosphatase PTEN induced an anti-inflammatory phenotype in myeloid cells. This resulted in protection of conditional knock-out mice in models of acute infection and inflammation.

A reduction in pro-inflammatory responses could however increase tumor burden. To address this question we induced colitis associated colon cancer in conditional PTEN-KO mice and found an increase in tumor burden and a reduction in survival in male KO mice. This was accompanied by increased numbers of splenic antigen-presenting cells (APC) expressing the immune checkpoint regulators PD-L1 and PD-L2. Furthermore, transcriptome analysis in these cells revealed a shift towards gene expression profiles found in professional APCs capable of cross-presentation. As expected, ex-vivo stimulated T-cells from KO-mice showed a reduction in proliferative capacity. These findings were further substantiated by findings in a second tumor model using implanted B16 melanoma cells. In this model myeloid PTEN-deficient mice showed a decrease in T-cell activation and a reduction in melanoma cell killing capacity.

Taken together, our findings show that genetic deletion of PTEN in cells of myeloid origin increases splenic APCs expressing immune checkpoint regulators resulting in a decrease in tumor immune surveillance. Our study shows that PI3K-inhibitors which are currently tested as anti-cancer drugs might have additional beneficial effects on immune cells by shifting their inflammatory phenotype.

Citation Format: Mario Kuttke, Emine Sahin, Julia Pisoni, Sophie Percig, Andrea Vogel, Daniel Kraemmer, Leslie Hanzl, Julia Stefanie Brunner, Hannah Paar, Klara Soukup, Angela Halfmann, Alexander Dohnal, Carl-Walter Steiner, Stephan Blüml, Jose Basilio, Bernhard Hochreiter, Manuel Salzmann, Bastian Hoesel, Günther Lametschwandtner, Robert Eferl, Johannes Schmid, Gernot Schabbauer. Myeloid PTEN deficiency impairs tumor immune surveillance via immune checkpoint inhibition. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 527.
Abstract 5271: Optimization and detection of focal somatic copy number variants in whole genome, whole exome and panel sequencing for tumor/normal matched pairs and tumor only analysis
Authors: Aldrich Jessica , Keats Jonathan J. , Christofferson Austin , Liang Winnie S. , Carpten John D. , Baumbach-Reardon Lisa , Craig David W.
Published: July 2016

Often in the clinical setting, tumor samples may be derived from historical tissue or from fresh frozen tissue and it may not be feasible to obtain normal tissue from the individual. Comparing unmatched tissues from different individuals possess a unique challenge of addressing common copy number variations not faced when comparing matched samples. In addition to the challenges of comparing unmatched samples, DNA extracted from samples preserved as formalin-fixed, paraffin-embedded (FFPE) tissue is often highly degraded and when compared to more intact DNA extracted from different source (e.g. blood) can increase the inherent noise in the system. Here we analytically characterize the accuracy and performance of algorithmic approaches for separating germline inherited copy number variation from somatic copy number changes, focusing on both filtering approaches and use of pooled reference samples sequenced under similar conditions. Example approaches include filtering known common copy number variation within 1000 Genomes Phase 3 and Database of Genomic Variants (DGV) Gold Standard. Additionally, we utilized a tumor/reference pool based analysis where a reference pool was constructed by equimolar pooling of multiple individuals. Determination of fold changes between tumor and reference was calculated by determining physical coverage of read pair fragments in 100 bases increments. Next, to address differences in sequencing performance between tumor and reference, the read depth data for each sample is collapsed/averaged into a lower resolution according to user-selected parameters (e.g. distance between points and read depth). Normalized log2 fold-changes between tumor and reference samples are then calculated and an adjustable smoothing window is applied. In addition, we utilize tumor allele frequencies of known heterozygous germline SNPs identified within the normal to both evaluate potential false positives and correct biases. Lastly, a segmentation algorithm is applied to summarize the individual log2 fold-changes into intervals with a constant copy number state. We will present the advantages and limitations of these approaches both when a germline normal is available and when tumor only analysis is necessary.

Citation Format: Jessica Aldrich, Jonathan J. Keats, Austin Christofferson, Winnie S. Liang, John D. Carpten, Lisa Baumbach-Reardon, David W. Craig. Optimization and detection of focal somatic copy number variants in whole genome, whole exome and panel sequencing for tumor/normal matched pairs and tumor only analysis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5271.