bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 3663: Discovery of sulfonamide-piperidinones as potent inhibitors of the MDM2-p53 protein-protein interaction
Authors: Li Zhihong , Fu Jiasheng , Rew Yosup , Gribble Michael W. , Canon Jude , Chen Ada , Eksterowicz John , Huang Xin , Jin Lixia , Lo Mei-Chu , McGee Lawrence R. , Osgood Tao , Saiki Anne Y. , Shaffer Paul , Sun Daqing , Wortman Sarah , Ye Qiuping , Yu Dongyin , Zhao Xiaoning , Zhou Jing , Oliner Jonathan D. , Olson Steve H. , Medina Julio C.
Published: August 2015

The p53 tumor suppressor is controlled by MDM2, which binds p53 and negatively regulates its transcriptional activity and stability. Many tumors overproduce MDM2 to impair p53 function. Therefore, restoration of p53 activity by inhibiting p53-MDM2 binding represents an attractive, novel approach to cancer therapy. We previously reported the discovery of AM-8553, a potent and selective piperidinone inhibitor of the MDM2-p53 interaction (Rew et al. J. Med. Chem. 2012, 55, 4936). We report here continued optimization of the N-alkyl substituent of this series, focused in particular on a previously underutilized interaction in a shallow cleft on the MDM2 surface that led to the discovery of a variety of extremely potent sulfonamides such as 14 with an IC50 of 5.3 nM in the cell proliferation assay. The compound 14 interacts specifically with the p53-binding pocket of MDM2 and releases the p53 protein from negative control. Treatment of cancer cells expressing wild-type p53 with sulfonamide 14 stabilizes p53 and activates the p53 pathway, leading to cell cycle arrest and apoptosis. The compound 14 showed excellent efficacy and caused tumor regression in the SJSA-1 tumor xenograft model.

Citation Format: Zhihong Li, Jiasheng Fu, Yosup Rew, Michael W. Gribble, Jude Canon, Ada Chen, John Eksterowicz, Xin Huang, Lixia Jin, Mei-Chu Lo, Lawrence R. McGee, Tao Osgood, Anne Y. Saiki, Paul Shaffer, Daqing Sun, Sarah Wortman, Qiuping Ye, Dongyin Yu, Xiaoning Zhao, Jing Zhou, Jonathan D. Oliner, Steve H. Olson, Julio C. Medina. Discovery of sulfonamide-piperidinones as potent inhibitors of the MDM2-p53 protein-protein interaction. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3663. doi:10.1158/1538-7445.AM2015-3663
Abstract 3695: Discovery of probes to evaluate the disruption of the protein-protein interactions mediated by RPA70N
Authors: Waterson Alex G. , Kennedy Phillip , Patrone James D. , Pelz Nicholas F. , Frank Andreas O. , Vangamudi Bhavatarini , Camper DeMarco V. , Souza-Fagundes Elaine M. , Feldkamp Michael D. , Olejniczak Edward T. , Rossanese Olivia W. , Chazin Walter J. , Fesik Stephen W.
Published: August 2015

Replication Protein A (RPA) is a major regulator of checkpoint activation and enhanced DNA repair in cancer cells. In response to genotoxic stress, the RPA complex binds to and protects ssDNA while serving as a scaffold to recruit critical checkpoint and DNA-damage response proteins through the N-terminal region of the 70 kDa subunit of RPA (RPA70N). RNAi against RPA has shown an expected toxicity against cancer cell lines. However, specific disruption of the RPA protein-protein interactions mediated by the RPA70N domain has the potential to produce selective killing of cancer cells without of cytotoxicity due to interference with its ssDNA-binding function. In order to accurately examine the therapeutic relevance of the inhibition of RPA function, we have sought to discover potent probe molecules that disrupt the interactions between RPA70N and its binding partners.

Here we describe the discovery of molecules to probe RPA function using complementary fragment-based and traditional high-throughput screening techniques. SAR studies and structure-based design concepts used to optimize the lead series of interest will be discussed along with the biochemical and cellular results obtained with the compounds.

Citation Format: Alex G. Waterson, Phillip Kennedy, James D. Patrone, Nicholas F. Pelz, Andreas O. Frank, Bhavatarini Vangamudi, DeMarco V. Camper, Elaine M. Souza-Fagundes, Michael D. Feldkamp, Edward T. Olejniczak, Olivia W. Rossanese, Walter J. Chazin, Stephen W. Fesik. Discovery of probes to evaluate the disruption of the protein-protein interactions mediated by RPA70N. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3695. doi:10.1158/1538-7445.AM2015-3695
Abstract 3706: Risk of bladder and kidney cancers in end-stage renal disease patients: a nationwide, population-based study in Taiwan
Authors: Kao Wei-Tang , Shen Cheng-Huang , Kiu Kee-Thai , Chen Hsin-An , Wu Chia-Chang , Wang Yuan-Hung
Published: August 2015

Chronic kidney disease (CKD) was the tenth leading cause of death in Taiwan. as the fifth stage of progressive CKD. Various therapeutic modalities including hemodialysis (HD),peritoneal dialysis (PD) and renal transplantation (RT) modify the risks of systemic chronic diseases in end-stage renal disease (ESRD) patients remains unclear.

A total of 18,081 newly diagnosed ESRD patients and 54,243 controls matched for age, gender and index date were recruited from the National Health Insurance Research Database in Taiwan. The ESRD status was confirmed by the registry of catastrophic illness. The incidence of cancer was identified through cross-referencing with the National Cancer Registry Database. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by a Cox proportional hazards model. Kaplan-Meier method were used for all analyses. Significant higher incidence rate ratios (IRRs) of bladder cancer of 7.0, 9.5 and 14.4 were found for ESRD patients undergoing HD, PD and RT, respectively. The IRRs of kidney cancer also represent a similar risk pattern. We observed that significant bladder cancer risks were observed among ESRD patients undergoing HD (HR = 10.0), PD (HR = 12.8) and RT (17.7) after the adjustment for age, gender and co-morbidities. In addition, significant kidney cancer risks of 11.2, 17.1 and 33.7 were also found for ESRD patients undergoing HD, PD and RT, respectively. In conclusion, different therapeutic modalities could modify the risks of bladder and kidney cancers in ESRD patients in Taiwan.

Citation Format: Wei-Tang Kao, Cheng-Huang Shen, Kee-Thai Kiu, Hsin-An Chen, Chia-Chang Wu, Yuan-Hung Wang. Risk of bladder and kidney cancers in end-stage renal disease patients: a nationwide, population-based study in Taiwan. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3706. doi:10.1158/1538-7445.AM2015-3706
Abstract 3713: Second malignant neoplasms after non-CNS embryonal tumors in North America
Authors: Zong Xuchen , Pole Jason D. , Grundy Paul , Mahmud Salaheddin M. , Parker Louise , Hung Rayjean J.
Published: August 2015

Background: Childhood cancer survivors are known to face an increased risk of adverse medical conditions related to the initial disease or cancer treatment; however, few studies have quantified the risk of second malignant neoplasms (SMNs) among survivors of childhood non-CNS embryonal cancer due to its rarity. In this study, we combined data from the U.S. and Canada to investigate the risk of SMNs.

Methods: Data from 13,107 survivors of childhood non-CNS embryonal tumors reported to the Surveillance Epidemiology and End Results (SEER) program in the U.S. and 8 population-based cancer registries in Canada (between 1973 to 2010) were analyzed. We calculated standardized incidence ratios (SIRs) for all types of second primaries by type of first primary, age at first cancer diagnosis, and follow-up duration. Expected numbers of SMNs were obtained by applying age-, sex-, calendar year-, and registry-specific cancer incidence rates to person-years contributed by these cancer survivors.

Results: One hundred and ninety SMNs were reported over 134,548 person-years of follow-up, with bone and joint cancer and leukemia being the most common SMNs (19% and 16% respectively). The SIR for all SMNs combined was 6.4 (95% CI: 5.53-7.35). Most site-specific SIRs were significantly increased, ranging from 36.4 (95% CI: 25.5-49.2) for bone and joint cancer, to 3.1 (95% CI: 1.54-5.2) for brain tumor. Among all the survivors, those who survived rhabdomyosarcoma carried the greatest risk of SMN development with SIR of 11.5 (95% CI: 8.7-14.6). Bone and joint tumors were mostly seen among retinoblastoma survivors, reflecting a markedly risk of 139.3 (95% CI: 85-207). When stratified by follow-up period, we observed that the risk patterns varied by SMN site. For example, the risk for a second malignancy in the thyroid remained significantly increased even after 20 years of follow-up, whereas the elevated risk of secondary leukemia persisted for 10 years but decreased rapidly afterwards. Details of stratified analyses by first primary tumor site, age at first diagnosis, and follow-up duration will be presented.

Conclusion: Survivors of childhood non-CNS embryonal tumors have increased risks of developing SMNs compared to the general population. Increased surveillance may explain the elevated risks within the first few years of the initial diagnosis, but treatment effects and shared etiology most likely account for the excess risk later in life.

Citation Format: Xuchen Zong, Jason D. Pole, Paul Grundy, Salaheddin M. Mahmud, Louise Parker, Rayjean J. Hung. Second malignant neoplasms after non-CNS embryonal tumors in North America. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3713. doi:10.1158/1538-7445.AM2015-3713
Abstract 3720: Diabetes and prostate cancer (CaP): Clinical characteristics and disparity in outcomes
Authors: Spangler Elaine , Zeigler-Johnson Charnita , Mitchell Jonathan , Rebbeck Timothy
Published: August 2015

Introduction: Disparities in prostate cancer (CaP) outcomes are poorly understood, but are likely caused by multiple factors. The presence of comorbidities may contribute to disparate outcomes in at least two ways: by altering the biological course of disease, and by influencing overall survival probabilities that impact treatment decisions. Diabetes has been associated with CaP in a variety of settings, and there is evidence that AA men suffer from diabetes at a higher rate than men of other races. We examined whether presence of diabetes is related to prostate cancer recurrence measured by post-prostatectomy biochemical (PSA) failure (BF).

Materials and methods: A prospective cohort of 554 European Americans (EA) and 184 African American (AA) CaP cases from the University of Pennsylvania were studied. We performed survival analysis for BF to evaluate the effect of diabetes on using Cox proportional hazards models adjusting for age, race, obesity, and Kattan score. Median post-prostatectomy follow-up was 40 months.

Results: Prevalence of diabetes was 6.3% overall (12% in AA and 5% in EA, p<0.0001). AA men were more likely to be obese then EA men (33% vs. 19%, p = 0.001). During post-prostatectomy follow-up, 52 (28%) AA and 187 (33%) EA men experienced BF; 47 (9%) diabetic men and 691 (5%) non-diabetic men experienced BF. Diabetic men were twice as likely to experience BF as men without diabetes (HR = 2.2, 95% CI: 1.26-3.92). Diabetes had a significant effect in both EA (HR = 2.1, 95% CI: 1.02-4.37) and AA (HR = 3.4, 95% CI: 1.16-10.0).

Conclusions. Being diabetic at time of CaP diagnosis increased the risk of prostate cancer recurrence, even after accounting for obesity and age. This effect was significant for both AA and EA, but the effect of diabetes appeared to be greater in AA. Diabetes may an important predictor of post-prostatectomy CaP outcomes.

Citation Format: Elaine Spangler, Charnita Zeigler-Johnson, Jonathan Mitchell, Timothy Rebbeck. Diabetes and prostate cancer (CaP): Clinical characteristics and disparity in outcomes. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3720. doi:10.1158/1538-7445.AM2015-3720
Abstract 3732: Detecting germline PTEN mutations among at-risk cancer patients: An age and gender-specific cost effectiveness analysis
Authors: Ngeow Joanne , Liu Chang , Zhou Ke , Frick Kevin , Matchar David B. , Eng Charis
Published: August 2015

Introduction

Cowden syndrome (CS) is an autosomal dominant disorder characterized by benign and malignant tumours. One-quarter of patients diagnosed with CS have pathogenic germline PTEN mutations, which increase risks of breast, thyroid, uterine, renal and other cancers. PTEN testing and regular, intensive cancer surveillance allow for early detection and treatment of these cancers for mutation positive patients and their relatives. Individual CS-related features, however, occur commonly in the general population, making it challenging for clinicians to identify CS-like patients to offer PTEN testing.

Methods:

We calculated the cost per mutation detected and analyzed the cost-effectiveness of performing selected PTEN testing among CS-like patients using a semi-quantitative score [PTEN-Cleveland Clinic (CC) score] compared with existing diagnostic criteria. In our model, first-degree relatives of the patients with detected PTEN mutations are offered PTEN testing. All individuals with detected PTEN mutations receive cancer surveillance.

Findings:

CC score at a threshold of 15 (CC15) allows costs ranging from $3,720 to 4,573 to detect one PTEN mutation, which is the lowest among different strategies tested. At a cost-effectiveness threshold of $100,000/Quality Adjusted Life Year (QALY), CC15 is the optimal strategy for female patients older than 50 years while CC10 is the optimal strategy for female patients younger than 50 years old and male patients of all ages. These results are robust in one-way sensitivity analyses. In probabilistic sensitivity analysis, CC10 and CC15 are the optimal strategies in 73% and 21% of the simulations respectively at a willingness to pay $100,000/QALY.

Conclusion:

CC score as a clinical risk calculator is a cost-effective pre-screening method to identify CS-like patients for PTEN germline testing.

Citation Format: Joanne Ngeow, Chang Liu, Ke Zhou, Kevin Frick, David B. Matchar, Charis Eng. Detecting germline PTEN mutations among at-risk cancer patients: An age and gender-specific cost effectiveness analysis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3732. doi:10.1158/1538-7445.AM2015-3732
Abstract 3736: Assessment of tobacco use within 30 days increases referral for cessation support
Authors: Cooper Samuel Lewis , Hoover Katherine , Garrett-Mayer Elizabeth , Cummings Kenneth Michael , Carpenter Matthew J. , Crowley Kelly , Marshall David T. , Warren Graham W.
Published: August 2015

Background: Cancer patients who self-report tobacco use within the past 30 days are at high risk for relapse and benefit from cessation support. However, there is little data on whether assessment of tobacco use within the past 30 days increases referral rates to a cessation program across cancer disease sites.

Methods: Structured tobacco assessments were administered to 426 new adult patients in a Radiation Oncology clinic at a single institution. Multiple logistic regression was used to assess if clinical aspects of cancer diagnosis (age, gender, race, disease site [head/neck or thoracic {HNT} vs. other], stage [advanced vs. early], and purpose [curative vs. palliative]) affected cessation service referral rates identified using assessment of tobacco use within the past 30 days.

Results: Complete medical and tobacco use data were compiled for 387 adult cancer patients (91%). Of these, 147 (38%) were women, 259 (67%) were Caucasian, 115 (30%) were black, 177 (46%) were diagnosed with HNT cancer, and 289 (74%) were being considered for curative cancer treatment. Ever smoking was reported in 273 patients (71%), and 83 (21%) reported current smoking everyday or some days. In 180 former smokers who reported time since last cigarette, 21 (12%) reported smoking within with past 30 days and 9 (7%) of these reported smoking within the past day or week. In 21 patients who were identified for cessation support through evaluation of smoking within the past 30 days, 6 (29%) were women, 7 (33%) were black, 15 (71%) were being considered for curative treatment, and 15 (71%) were diagnosed with a HNT cancer. Multiple logistic regression identified that younger age (10 yr OR 2.41, 95% CI 1.47 - 3.98) and HNT cancer (OR 8.13, 95% CI 2.2-30.3) but not gender, race, stage, and purpose were significantly associated with referral based on assessment of tobacco use within the past 30 days. Identification of smoking within the past 30 days increased cessation referrals by 25% from 83 to 114 patients.

Conclusions: Assessment of tobacco use within the past 30 days increased referrals to a smoking cessation program from a Radiation Oncology clinic using a standardized tobacco assessment. In clinical trials and practice, including this question has particular benefit for younger patients and patients with head/neck or thoracic tumors.

Citation Format: Samuel Lewis Cooper, Katherine Hoover, Elizabeth Garrett-Mayer, Kenneth Michael Cummings, Matthew J. Carpenter, Kelly Crowley, David T. Marshall, Graham W. Warren. Assessment of tobacco use within 30 days increases referral for cessation support. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3736. doi:10.1158/1538-7445.AM2015-3736
Abstract 3747: Identification of NSCLC biomarkers underlying quantifiable drug-induced clonal fitness
Authors: Jameson Katherine L. , Frick Peter L. , Tyson Darren R. , Yankeelov Thomas E. , Quaranta Vito
Published: August 2015

Lung cancer accounts for nearly 20% of all cancer-related deaths worldwide. Subsets of non-small-cell lung cancer (NSCLC; >80% of all lung cancers) harboring activating epidermal growth factor receptor (EGFR) mutations are highly sensitive to erlotinib, a small-molecule EGFR tyrosine kinase inhibitor. However, clinical responses to erlotinib are variable and limited in duration as all tumors eventually relapse. Clonal heterogeneity is thought to be a major cause of relapse, but it has been difficult to quantify in drug-sensitive cancer cell populations. To overcome this obstacle, we quantify clonal fitness via live-cell imaging as a drug-induced proliferation (DIP) rate that incorporates cell division, death, and quiescence into a single metric. This fitness rate varies across cell types from positive (division prevails) to negative (death prevails) and, unlike traditional IC50 measurements, can effectively discriminate intricate degrees of drug sensitivity. Moreover, in monoclonal sublines isolated naïve-to-drug from NSCLC parental cell lines, erlotinib-treated DIP rates calculated in vitro predict the long-term growth rates (250+ days) of in vivo tumor xenografts. Using global proteomics across a panel of monoclonal sublines, we have characterized networks of biomarkers that act as molecular determinants of phenotypic drug fitness. We have identified unsuspected molecular correlates in the EGFR and AKT pathways and are currently investigating whether they can act as lead targets for small molecule inhibition in combination therapies. Our data indicate that a multi-scale systems approach integrating molecular subtyping with quantifiable clonal fitness can yield insights into clonal heterogeneity and lead to novel strategies to overcome tumor relapse.

Note: This abstract was not presented at the meeting.

Citation Format: Katherine L. Jameson, Peter L. Frick, Darren R. Tyson, Thomas E. Yankeelov, Vito Quaranta. Identification of NSCLC biomarkers underlying quantifiable drug-induced clonal fitness. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3747. doi:10.1158/1538-7445.AM2015-3747
Abstract 3762: The landscape of therapeutic targetable fusions
Authors: Yoshihara Kosuke , Wang Qianghu , Torres-Garcia Wandaliz , Zheng Siyuan , Vegesna Rahulsimham , Kim Hoon , Verhaak Roel GW
Published: August 2015

Gene fusions are an important class of cancer-contributing somatic alteration, and have an important significance as a tumor-initiating event and as a molecular therapeutic target for specific tumors. We analyzed RNA sequencing, DNA copy number and gene mutation data from 4,366 primary tumor samples to comprehensively detect fusion events in 13 tumor types. To reduce the number of false-positive predictions, we developed strict quality criteria on the basis of gene homology, transcript allele fraction (TAF), and partner gene variety. In addition, we used fusions detected in RNAseq data from 364 normal tissue samples to extract tumor-specific fusions. In total, 7,887 fusion transcripts with high confidence were detected across 13 tumor types. Our fusion prediction was validated by supporting evidence for a genomic rearrangement for 78 of 79 fusions in 48 glioma samples where whole genome sequencing data was available. Fusion transcript frequency was positively correlated with the levels of genomic instability in cancers, whereas tumor samples harboring fusions contained statistically significantly fewer driver gene mutations. We identified 221 fusion transcripts involving a tumor suppressor gene and these were wildtype in majority (98.2%), suggesting the fusion has a disruptive effect and a role in tumorigenesis. We identified at least one in-frame protein kinase fusion in 324 of 4,366 samples (7.4%). Potentially therapeutic targetable kinase fusions such as ALK, ROS, RET, NTRK, and FGFR gene families were detected in thyroid carcinoma (8.7%), glioblastoma (4.4%), bladder carcinoma (3.3%), lung squamous cell carcinoma (2.3%), lung adenocarcinoma (1.6%), lower grade glioma (1.5%), and head and neck cancer (1.0%), suggesting a potential for application of kinase inhibitors for multiple tumor types. In-frame fusion transcripts involving histone methyltransferase or histone demethylase genes, which may also be considered as therapeutic targets, were detected in 111 samples (2.5%). In summary, the landscape of transcript fusions detected across a large number of tumor samples revealed fusion events with clinical relevance that have not been previously recognized. Our findings support the concept of basket clinical trials where patients are matched with experimental therapies based on their genomic profile rather than the tissue where the tumor originated.

Citation Format: Kosuke Yoshihara, Qianghu Wang, Wandaliz Torres-Garcia, Siyuan Zheng, Rahulsimham Vegesna, Hoon Kim, Roel GW Verhaak. The landscape of therapeutic targetable fusions. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3762. doi:10.1158/1538-7445.AM2015-3762
Abstract 3764: Modeling tumors in their environment
Authors: Delgado Juan , Yates James
Published: August 2015

Tumour microenvironment plays an important role in tumour growth. However, the composition and architecture of the tumour stroma varies dramatically across animal models and the clinic. In these animal models, not only the tumour formation, but the whole environment (stroma, mechanical stress…) is very different to the clinical tumour “context”. Nevertheless, explant models show a conserved stroma-tumour architecture. Keeping this in mind, we developed a mathematical model that not only captures tumour growth in animals, but may in the future also translate to patients.

We propose a multiscale model to mimic tumour microenvironment and tumour cell co-development. The model is an agent-based model. The agents (epithelial clusters) represent 10 cells each with 5 transit states (G1, S, G2M, Hypoxic and Necrotic). Also, stromal cells may be recruited, can migrate and deliver blood to the tumour. The transitioning probabilities across the cell cycle are characterised by a pure time delay, followed by an exponential decrease. Further, profiles of chemokines and oxygen are computed as an approximation of the Fick Diffusion equations. These profiles trigger cell recruitment and proliferation. Additionally, cells may undergo hypoxia and become necrotic. All this computed by the Gillespie algorithm method in a 3D lattice in matlab 13b.

The model successfully predicts tumour growth for a number of xenografted cell lines and explants of different cell origin. The patterns of the stromal architecture have been validated against IHC images from explant tumours at the end of study. For the validation, we developed an advanced imaging method to score tumour heterogeneity spatially from different immunostains.

By interrogating the model, we can demonstrate that explant tumours - unlike xenografts - are not completely out of the clinical “context”. Our model being able to mimic the different phenotypes of heterogeneity observed across explants of diverse tissue origins (or patients), demonstrates that this method is potentially very broad. In future versions, the model will include more characteristics of the stroma, which would help us understand reasons why patterns of the stromal complexity form and affect tumour development and its treatment; both in animal studies and the clinic. The model will be contrasted with clinical data.

Citation Format: Juan Delgado, James Yates. Modeling tumors in their environment. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3764. doi:10.1158/1538-7445.AM2015-3764
Abstract 3776: HnRNP A1 regulates cell cycle and proliferation in oral squamous cancer cells
Authors: Yu Cheng , Guo Jihua , Jia Jun , Jia Rong , Fan Mingwen
Published: August 2015

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in human head and neck neoplasms. Despite the improvement of therapeutic approaches, reducing high mortality is still the major challenge of OSCC. However, the molecular pathogenesis of OSCC remains largely unclear, which hinders the development of effective preventive and therapeutic methods. Alternative splicing of pre-mRNA has been implicated to be involved in tumorigenesis. Splicing factors play key roles in the regulation of alternative splicing. HnRNP A1 is an important multi-function splicing factor and closely related to tumorigenesis. It has been reported to be overexpressed in multiple types of tumors. However, the function of A1 in cell cycle and proliferation remains unclear. We found that hnRNP A1 was overexpressed in OSCC tissues and cells by immunohistochemistry and western blotting. Down-regulation of hnRNP A1 with siRNA significantly retarded the growth of OSCC cells and induced G2/M arrest. DNA chip assay showed that the expression of a number of target genes associated with G2/M phase are regulated by hnRNP A1. These findings suggest that hnRNP A1 plays key roles in the regulation of cell cycle progression and pathogenesis of OSCC.

Citation Format: Cheng Yu, Jihua Guo, Jun Jia, Rong Jia, Mingwen Fan. HnRNP A1 regulates cell cycle and proliferation in oral squamous cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3776. doi:10.1158/1538-7445.AM2015-3776
Abstract 3780: Aven-mediated checkpoint kinase control regulates proliferation and resistance to chemotherapy in osteosarcoma cells
Authors: Baranski Zuzanna , Booij Tijmen T.H. , Jong Yvonne de , Oosterwijk Jolieke van , Cleton Anne-Marie , Price Leo , Water Bob van de , Bovée Judith V.M.G. , Hogendoorn Pancras C.W. , Danen Erik
Published: August 2015

Osteosarcoma is the most common primary bone malignancy with relatively high incidence in young people. Here, we found that expression of Aven was inversely correlated with metastasis-free survival in osteosarcoma patients and is increased in metastases compared to primary osteosarcoma biopsies. Also in chondrosarcoma, the second most common bone sarcoma, expression correlated with increased histological grade. Aven is an adaptor protein that has been implicated in anti-apoptotic signaling and serves as an oncoprotein in acute lymphoblastic leukemia. In human osteosarcoma cells, silencing Aven triggered a G2 cell cycle arrest. Chk1 protein levels were attenuated and ATR-Chk1 DNA damage response signaling in response to chemotherapy was abolished in Aven-depleted osteosarcoma cells while ATM, Chk2, and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven-controlled ATR-Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix-embedded cultures Chk1 inhibition effectively sensitized human osteosarcoma cells to chemotherapy. Together, these findings implicate Aven in ATR-Chk1 signaling and point towards Chk1 inhibition as a strategy to sensitize osteosarcomas to chemotherapy.

Citation Format: Zuzanna Baranski, Tijmen T.H. Booij, Yvonne de Jong, Jolieke van Oosterwijk, Anne-Marie Cleton, Leo Price, Bob van de Water, Judith V.M.G. Bovée, Pancras C.W. Hogendoorn, Erik Danen. Aven-mediated checkpoint kinase control regulates proliferation and resistance to chemotherapy in osteosarcoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3780. doi:10.1158/1538-7445.AM2015-3780
Abstract 3786: Novel regulation of cyclin D1 stability and the DNA damage response
Authors: Guessous Fadila , Heo Jinho , Vaddadi Naga , Abbas Tarek
Published: August 2015

Deregulation of the cell division cycle is critical for cancer development. Transition from G1 to S phase of the cell cycle is promoted by D-type cyclins (D1, D2 and D3). Cyclin D1 is a critical regulator of cell cycle progression due to its ability to activate cyclin dependent kinases (CDK) 4 and 6, which phosphorylate and inactivate the retinoblastoma protein (pRb) and activates the transcription factor E2F1 to promote the expression of genes essential for G1/S progression. Importantly, mutations in the tumor suppressor gene RB1 or inactivation of the RB tumor suppressor pathway occurs in almost all human malignancies and one such mechanism involves cyclin D1 overexpression. Even in cancer cells with amplified or elevated cyclin D1 mRNA, the Cyclin D1 protein rapidly declines as cells progress through the G1 phase of the cell cycle to reach undetectable levels in S-phase, and this is thought to be dependent on the Skp1-Cul1-F-box protein (SCF) E3 ubiquitin ligase complex. The identity of the E3 ubiquitin ligase that is specifically involved in downregulating cyclin D1 during S-phase of the cell cycle or the functional significance of cyclin D1 downregulation however, remains unknown, as recent genetic studies in mice demonstrated that the steady state levels or stability of cyclin D1 protein, are not altered following the inactivation of the known regulators of cyclin D1 stability. Using a genetic si-RNA-based screen, we have identified a novel E3 ubiquitin ligase; SCF-FBXW5, which specifically interacts with and downregulates cyclin D1 protein, both in unperturbed proliferating cancer cells and following DNA damage. Importantly, inactivation of this E3 ubiquitin ligase inhibits the proliferation of cancer cells primarily through cyclin D1-dependent inhibition of S-phase progression and sensitizes cancer cells to DNA damage induced by UV or ionizing radiation. These findings identify a novel axis of regulating cyclin D1 stability in cancer cells with implications for targeting this axis to inhibit cyclin D1-driven cancers.

Citation Format: Fadila Guessous, Jinho Heo, Naga Vaddadi, Tarek Abbas. Novel regulation of cyclin D1 stability and the DNA damage response. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3786. doi:10.1158/1538-7445.AM2015-3786
Abstract 3799: Cordyceptin induces apoptosis through repressing hTERT expression and inducing extranuclear export of hTERT
Authors: Kim Nam Deuk , Kim Gi-Young , Choi Yung Hyun
Published: August 2015

Cordycepin is an adenosine analog originally extracted from Cordyceps militaris that possesses many pharmacological effects including immune activation and antioxidant and antitumor effects. However, the underlying relationship between apoptosis and telomerase activity in response to cordycepin exposure has not been investigated. In this study, we found that cordycepin-induced apoptosis of human leukemia cells (H937 and THP-1 cells) was associated with inactivation of telomerase and downregulation of human telomerase reverse transcriptase (hTERT) as well as the transcription factors c-Myc and Sp1, which are required for basal transcription from the hTERT gene promoter. Cordycepin also attenuated the activation of phosphoinositide-3-kinase (PI3K)/Akt signaling, thereby reducing phosphorylation and nuclear translocation of hTERT. We further showed that the PI3K inhibitor LY29004 significantly decreased telomerase activity in cordycepin-treated cells and increased cordycepin-induced cell death. These findings demonstrate that cordycepin is cytotoxic to human leukemia cells and suppresses telomerase activity through transcriptional and post-translational suppression of hTERT by inactivating the PI3K/Akt signaling pathway.

Citation Format: Nam Deuk Kim, Gi-Young Kim, Yung Hyun Choi. Cordyceptin induces apoptosis through repressing hTERT expression and inducing extranuclear export of hTERT. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3799. doi:10.1158/1538-7445.AM2015-3799
Abstract 3819: A simple method for selectively isolating small size circulating cell-free DNA
Authors: Rodriguez Milka A. , Conroy Amanda , Li Wei wei
Published: August 2015

Elevated levels of circulating cell-free DNA (ccfDNA) in plasma/serum have been associated with several pathological and clinical disorders such as cancer. It was demonstrated that ccfDNA of clinical importance exists predominantly as ∼170 bp fragments in mononucleosomal complexes and isolation of this DNA is challenging. Traditional methods for isolation of ccfDNA have been unreliable since they cannot selectively capture small size DNA from mononucleosomes. Here we describe a simple and reliable method which can be used for selectively isolating ccfDNA from plasma/serum. Different amounts of HeLa mononucleosomes (10-500 ng) were spiked into 0.5 ml of bovine plasma to mimic ccfDNA. First, nucleosomal complexes were captured using size-fractionation magnetic beads. The DNA in the captured nucleosomal complexes was then purified with DNA purification beads. As a control, 500 ng of polynucleosomes (DNA size 2270 bps) were simultaneously spiked with mononucleosomes into 0.5 ml of plasma and subjected to the isolation procedures described above. Fluorescent quantification showed 70-100% recovery of DNA from plasma with the highest recovery (100%) at lower concentrations of spiked mononucleosomes (10 ng). Bioanalyzer results further showed that only 170 bp peak size fragments were present for mononucleosomes alone or for both mono- and poly-nucleosomes spiked into plasma. No peak was observed for polynucleosomes spiked into plasma. These results demonstrate that this method is highly selective and specific for isolation of small size ccfDNA generated from mononucleosomes in plasma and would benefit early cancer detection that uses ccfDNA as biomarkers.

Citation Format: Milka A. Rodriguez, Amanda Conroy, Wei wei Li. A simple method for selectively isolating small size circulating cell-free DNA. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3819. doi:10.1158/1538-7445.AM2015-3819
Abstract 382: Identification and characterization of circulating tumor cells with multiplexed Quantum Dot conjugated antibodies
Authors: Zhou Lanlan , Matthew Elizabeth M. , Dicker David T. , El-Deiry Wafik S.
Published: August 2015

As non-invasive real-time liquid biopsy, circulating tumor cell (CTC) detection and characterization is one of the most active areas in translational cancer research, with 627 clinical trials having that include analysis of CTCs as a biomarker. We used breast cancer cells, prostate cancer cells and melanoma cells spiked into normal donor whole blood and captured with high porosity micro-filters followed by immunofluorescence staining. DAPI, CD45 conjugated with QDot525, CK8/18/19 conjugated with QDot605 and high molecular weight-melanoma associated antigen (HMW-MAA) conjugated with QDot705 were stained to identify CTCs. ER conjugated with QDot800 and PSA conjugated with QDot655 were stained to characterize CTCs. The CTC recovery rate was compared with the report from the US Food and Drug Administration- approved CellSearch® system (Veridex). Multiplexed tumor marker staining results were compared with single staining with fluorescently-labeled secondary antibody. Our study demonstrates that CTC multiplexed analysis has the potential for further genetic characterization of CTCs and offers potential insights into therapeutic targeting and resistance mechanisms.

Citation Format: Lanlan Zhou, Elizabeth M. Matthew, David T. Dicker, Wafik S. El-Deiry. Identification and characterization of circulating tumor cells with multiplexed Quantum Dot conjugated antibodies. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 382. doi:10.1158/1538-7445.AM2015-382
Abstract 3822: SOX17 gene promoter methylation in high-grade serous epithelial ovarian cancer
Authors: Giannopoulou Lydia , Chebouti Issam , Pavlakis Kitty , Kasimir-Bauer Sabine , Lianidou Evi S.
Published: August 2015

Introduction: Impaired DNA methylation patterns hold promise as cancer biomarkers. SOX17, a member of the SOX family of transcription factors, is conserved in many species and plays critical roles in the regulation of development and stem/precursor cell function, at least partly through repression of the canonical Wnt/beta-catenin signaling pathway. Global analysis of CpG island hypermethylation and gene expression in colorectal cancer cell lines revealed that SOX17 gene silencing is associated with DNA hypermethylation. We have already shown that this gene is hypermethylated in circulating tumor cells and circulating tumor DNA of patients with breast cancer (Chimonidou et al, Clin Chem 2011, Chimonidou et al, Clin Chem, 2013). High grade serous ovarian cancer (HGSC) is the most common histological subtype of ovarian cancer, with a worse disease prognosis and overall survival. In this study, we investigated for the first time the status of SOX17 promoter methylation in patients with high grade serous ovarian cancer.

Materials and methods: HGSC tumors (FFPEs) from ovarian cancer patients belonging to an independent group (n = 78) and a training group (n = 47) were analyzed.

For the evaluation of the specificity of our results, a small group of 10 corresponding normal tissues from the first ten individuals of the training group was also analyzed. Genomic DNA was isolated from all samples, and then was modified by Sodium Bisulfite (SB). All SB converted DNA samples were analyzed by a real time Methylation Specific PCR (MSP) assay, for detecting SOX17 promoter methylation. The IGROV1 ovarian cancer cell line was used as a positive control in all procedures.

Results: In the training group, SOX17 promoter methylation was detected in 25/47 ovarian tumor samples (53.2%) and in 5/10 corresponding normal tissues. The same 5/10 matched pathological samples of the training group, were also found methylated for the SOX17 gene. In the independent group, SOX17 promoter methylation was observed in 61/78 tumor samples (78.2%).

Conclusion: Our results indicate for the first time that SOX17 promoter methylation is a frequent event in high grade serous ovarian cancer. Further investigation is required to determine the prognostic significance of SOX17 promoter methylation status in ovarian cancer and correlate these findings with patients’ clinicopathological characteristics.

Citation Format: Lydia Giannopoulou, Issam Chebouti, Kitty Pavlakis, Sabine Kasimir-Bauer, Evi S. Lianidou. SOX17 gene promoter methylation in high-grade serous epithelial ovarian cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3822. doi:10.1158/1538-7445.AM2015-3822
Abstract 3829: DNA methylation profile in papillary thyroid cancer according to BRAF (V600E) mutation
Authors: Beltrami Caroline Moraes , dos Reis Mariana Bisarro , Barros-Filho Mateus Camargo , Marchi Fabio Albuquerque , Kuasne Hellen , Ambatipudi Srikant , Herceg Zdenko , Kowalski Luiz Paulo , Rogatto Silvia Regina
Published: August 2015

Background: Thyroid cancer is an important health burden and the endocrine neoplasia with highest incidence in worldwide. Papillary thyroid cancer (PTC), the most common thyroid malignancy, is frequently associated with BRAF V600E mutation. This mutation occurs in around 45% of PTC cases and it has been associated with aberrant gene methylation. This finding suggests an association between genetic and epigenetic alterations in tumor development. The goal of this study was to evaluate the methylation profile in PTC samples according to BRAF mutation.

Patients and Method: Forty-two PTC were included in this study (28 positive for BRAF V600E mutation). Normal and tumoral samples were obtained from patients submitted to total thyroidectomy and radioiodine therapy. The pyrosequencing method was used to detect and quantify the BRAF V600E mutation in tumor samples. The methylation analysis was performed by microarray platform Methylation 450 Human Infinium®BeadChip (Illumina), according to the manufacturer's recommendations. The data were normalized and analyzed using SVA, wateRmelon and LIMMA package. It was considered only probes with Delta-Beta (β) = 0.1 and p value ≤ 0.001. Integrative analyses were performed using expression data generated from previous analysis. The findings were compared with 56 samples from The Cancer Genome Atlas (TCGA). Genes enrichment to biological pathways were performed using Ingenuity Pathway Analysis software.

Results: It was identified 404 differentially methylated probes (291 hypomethylated and 113 hypermethylated) of which 195 were validated by TCGA. After the integrative analysis with expression data, nine TOP genes (INF2, TACSTD2, RAB15, TM7SF4, GJB3, CDSN, BHLHE41, GTF2IRD1, CXXC5) were selected with hypomethylation and overexpression. Three of them, BHLHE41, CDSN and INF2, were enriched to cancer and endocrine system disorders pathways (P = 4,47×10−2), highlighting the relevance of these genes in PTC

Conclusion: This study point out putative drivers in PTC according to BRAF mutation revealing epigenetic mechanisms that contributes with cell proliferation and aggressiveness in thyroid carcinoma.

Citation Format: Caroline Moraes Beltrami, Mariana Bisarro dos Reis, Mateus Camargo Barros-Filho, Fabio Albuquerque Marchi, Hellen Kuasne, Srikant Ambatipudi, Zdenko Herceg, Luiz Paulo Kowalski, Silvia Regina Rogatto. DNA methylation profile in papillary thyroid cancer according to BRAF (V600E) mutation. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3829. doi:10.1158/1538-7445.AM2015-3829
Abstract 3908: Periostin mediated TNFα and IL-17 induced collagen deposition: Potential role in liver fibrosis
Authors: Tiriveedhi Venkataswarup
Published: August 2015

Background: The pro-inflammatory cytokines, tumor necrosis factor (TNF)-α, and interleukin (IL)-17, have been implicated in the pathogenesis of liver fibrosis. In this study, we investigated the role of TNFα and IL-17 towards induction of profibrotic factor, periostin.

Methods: HepG2 cells were cultured and treated with inflammatory cytokines, TNFα and IL-17. Computational promoter sequence analysis of the periostin promoter was performed to define the putative binding sites for transcription factors. Transcription factors were analyzed by Western blot and Chromatin Immunoprecipitation. Periostin and transcription factor expression analysis was performed by RT-PCR, Western blot, and fluorescence microscopy. Type I collagen expression from fibroblast cultures was analyzed by Western blot and Sircol soluble collagen assay.

Results: Activation of HepG2 Cells with TNFα and IL-17 enhanced the expression of periostin (3.5 and 4.4 fold, respectively p<0.05) compared to untreated cells. However, combined treatment with both TNFα and IL-17 at similar concentration demonstrated a 13.3 fold increase in periostin (p9.1 fold, p<0.01), indicative of a direct fibrogenic effect of TNFα and IL-17.

Conclusion: TNFα and IL-17 induced fibrogenesis through cJun and STAT-3 mediated expression of profibrotic biomarker, periostin. Therefore, periostin might serve as a novel biomarker in early diagnosis of liver fibrosis.

Note: This abstract was not presented at the meeting.

Citation Format: Venkataswarup Tiriveedhi. Periostin mediated TNFα and IL-17 induced collagen deposition: Potential role in liver fibrosis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3908. doi:10.1158/1538-7445.AM2015-3908