bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2869: A three-protein cytokine signature that correlates with the prognosis of osteosarcoma
Authors: Flores Ricardo J. , Li Yiting , Kelly Aaron , Lau Ching , Man Tsz-Kwon
Published: May 2015

Osteosarcoma (OS) is the most common malignant bone tumor in pediatrics. Despite the use of surgery and chemotherapy, the survival rate of patients who develop a metastatic disease or a poor response towards the chemotherapy remains dismal. Identification of novel biomarkers for early prognostication will facilitate risk-based stratification before the treatment is initiated, so that the high-risk patients can be treated more appropriately to increase their chance of survival. Others and we have previously reported that cytokines and chemokines were implicated in OS. In this study, we employed highly sensitive Luminex beads assays to investigate 90 cytokines/chemokines and receptors on a cohort of 40 OS plasma samples collected at diagnosis from the Texas Children's Hospital. The protein expression data were analysed to identify candidate biomarkers that correlate with the chemotherapy response, initial metastatic status, and overall survival. Then, the candidates were validated in a large set of 250 serum samples obtained from the Children's Oncology Group. Our results show that a three-protein signature consisting of CXCL9, CXCL10 and CXCL11, all ligands of the CXCR3 receptor, is significantly associated with survival. Interestingly, the CXCR3-axis has been previously implicated in an OS mouse model, but its role in human is still not known. Hence, the next step is to validate these prognostic biomarkers in an independent cohort of OS patient samples. In addition, we will test the expression of these molecules and their receptor in tumor samples to identify potential therapeutic targets. In summary, we characterized the expression of circulating cytokines/chemokines in osteosarcoma samples and identified candidate prognostic biomarkers that are linked to the CXCR3-axis. A further study of these molecules may allow us to develop a biomarker approach for early prognostication and a novel therapeutic approach for treating high-risk OS.

Citation Format: Ricardo J. Flores, Yiting Li, Aaron Kelly, Ching Lau, Tsz-Kwon Man. A three-protein cytokine signature that correlates with the prognosis of osteosarcoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2869. doi:10.1158/1538-7445.AM2014-2869
Abstract 2871: Correlation between number and sites of metastases and differential pretreated EBV DNA load profiles and their effects on outcomes in patients with metastatic nasopharyngeal carcinoma
Authors: Wang Hung-Ming , Chang Kai-Ping , Lin Tung-Liang , Huang Shiang-Fu , Tsang Ngan-Ming , Chan Sheng-Chieh , Hsu Cheng-Lung
Published: May 2015

Background: To investigate the relationship between pretreatment plasma EBV DNA copy number and sites and numbers of metastases in patients with nasopharyngeal carcinoma (NPC).

Methods: One hundred and thirty-three patients with metastatic NPC were treated at outpatient department. Their plasma EBV DNA concentrations were determined by real-time quantitative PCR.

Results: The overall patient response rate after 3-6 months of treatment was 48.1%. Pretreatment plasma EBV DNA concentrations were lower in patients with solitary nodule (≤5,000 copies/mL, 18/25 [72%] vs. multiple nodules, 49/128 [45.4%], P=0.025) or pure lung metastases (≤5,000 copies/mL, 19/21 [90.5%] vs. not lung metastases alone 48/112 [42.9%], P<0.001) and higher in patients with liver involvement, alone or combined with other organs (≤5,000 copies/mL, 18/54 [33.3%] vs. non-liver metastases 49/79 [62%], P=0.001); and bone related metastases (≤5,000 copies/mL, 33/83 [39.8%] vs. non-bone metastases 34/50 [68%], P=0.002). Moreover, plasma EBV DNA concentration was correlated with overall survival (OS) (≤5,000 vs. >5,000 copies/mL, median OS, 26 vs. 10 months; HR, 2.852; P<0.001).

Conclusions: Pretreatment plasma EBV DNA copy number correlated with number and sites of metastases and with OS in patients with metastatic NPC.

Citation Format: Hung-Ming Wang, Kai-Ping Chang, Tung-Liang Lin, Shiang-Fu Huang, Ngan-Ming Tsang, Sheng-Chieh Chan, Cheng-Lung Hsu. Correlation between number and sites of metastases and differential pretreated EBV DNA load profiles and their effects on outcomes in patients with metastatic nasopharyngeal carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2871. doi:10.1158/1538-7445.AM2014-2871
Abstract 2900: IMCgp100: A novel bi-specific biologic for the treatment of malignant melanoma
Authors: Hassan Namir J. , Bossi Giovanna , Baker Debbie , Adams Katherine , Harper Jane , Dukes Joseph , Liddy Nathaniel , Paston Samantha , McGrath Yvonne , Mahon Tara , Molloy Peter , Sami Malkit , Baston Emma , Cameron Brian , Johnson Andrew , Vuidepot Annelise , Linette Gerry , Kalos Michael , June Carl , Jakobsen Bent
Published: May 2015

Despite significant advances in the treatment of metastatic melanoma, long-term remission for the majority of patients remains elusive. Kinase inhibitors provide potent but short-term responses for a significant proportion of patients and immunotherapy elicits long-term responses with the prospect of cure, but only in a minority.

IMCgp100 is a novel bi-specific immunotherapy comprising a soluble, affinity enhanced, T cell receptor (TCR) specific for the melanoma-associated antigen gp100, fused to an anti-CD3 specific antibody fragment (scFv). The engineered TCR portion of the drug targets and binds the gp100 peptide 280-288 antigen, which is over-expressed and presented by HLA-A2 on the surface of melanoma cells. The anti-CD3 scFv portion captures and redirects T cells to kill the melanoma cells, while normal antigen negative tissues are unaffected. Here, we present data which provides the foundation for the clinical observations. In vitro, IMCgp100 is demonstrated to potently redirect T cells from late stage cancer patients to target melanoma tumors exhibiting HLA-down regulation, even in the presence of high numbers of regulatory T cells. Target cell killing is observed within hours and is specific for gp100. In addition killing is associated with the release of various pro-inflammatory cytokines and chemokines as well as cross-presentation of gp100 and other melanoma-associated antigens by dendritic cells. Thus, IMCgp100 demonstrates the potential to elicit potent short-term responses and trigger longer-term anti melanoma activity in vivo.

IMCgp100 is undergoing Phase I clinical testing in patients with advanced malignant melanoma; with the maximum tolerated dose having been established. The drug is well tolerated with evidence of tumor shrinkage. Analyses of serum samples obtained from patients on the trial demonstrate T cell mobilisation and transient drug mediated increases in various cytokines and chemokines, some of which are reported to play a key role in anti-melanoma responses. These data support the potential of IMCgp100 as an effective treatment for malignant melanoma.

Citation Format: Namir J. Hassan, Giovanna Bossi, Debbie Baker, Katherine Adams, Jane Harper, Joseph Dukes, Nathaniel Liddy, Samantha Paston, Yvonne McGrath, Tara Mahon, Peter Molloy, Malkit Sami, Emma Baston, Brian Cameron, Andrew Johnson, Annelise Vuidepot, Gerry Linette, Michael Kalos, Carl June, Bent Jakobsen. IMCgp100: A novel bi-specific biologic for the treatment of malignant melanoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2900. doi:10.1158/1538-7445.AM2014-2900
Abstract 2905: The activity of a new class of biologics: trastuzumab conjugates designed to treat brain metastases of HER2+ breast cancers
Authors: Vitalis Timothy , Jefferies Wilfred , Gabathuler Reinhard
Published: May 2015

Trastuzumab, a monoclonal antibody against HER2, is an effective therapy for the treatment of peripheral HER2+ breast cancer. However, a significant number of patients eventually succumb to the disease due to brain metastases. In these patients trastuzumab is no longer effective because the blood brain barrier reduces distribution of trastuzumab to the brain tumor. In this study, we conjugate trastuzumab to melanotransferrin (MTf), a protein of the transferrin family, which has been shown to cross the blood brain barrier, and characterize its anti-tumor activity. We used thiol-malemide linkage to conjugate trastuzumab to MTf and generated a mixture of trastuzumab-MTf species of varying molar ratios. Size exclusion chromatography was used to enriched for the 1:1 heterodimer fraction and this fraction was designated as BT2111. The activity of BT2111 against human HER2+ breast cancer cell lines was tested with a cytotoxicity assay, an antibody dependent cellular cytotoxicity (ADCC) assay, and in a peripheral tumor xenograft model. At equimolar equivalents, BT2111 had greater anti-tumor activity than trastuzumab against HER2+ human breast cancer cell lines (SKBR3 and BT474). Furthermore, significant ADCC activity directed against BT474 cells was observed when cells were treated with BT2111 and incubated with human NK cells. Finally, both BT2111 and trastuzumab completely inhibited the growth of peripheral xenograft tumors (BT474) in athymic mice over the course of the experimental period (5-6 weeks). Conjugation of trastuzumab to MTf does not alter the in vivo anti-tumor activity of trastuzumab, supporting the conclusion that HER2 binding and Fc receptor binding was not significantly affected by conjugation. BT2111 is the first example of a new class of biologics that demonstrates the ability to inhibit the growth of peripheral HER2+ tumors and has the added benefit of penetrating the brain for the treatment of HER2+ brain metastases.

Citation Format: Timothy Vitalis, Wilfred Jefferies, Reinhard Gabathuler. The activity of a new class of biologics: trastuzumab conjugates designed to treat brain metastases of HER2+ breast cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2905. doi:10.1158/1538-7445.AM2014-2905
Abstract 2952: Aberrant accumulation of 2-hydroxyglutarate in human breast cancer with myc activation
Authors: Mishra Prachi
Published: May 2015

Metabolite addiction of tumors may represent an Achilles heel for cancer cells and an opportunity for therapeutic intervention. Recently, using an untargeted discovery approach and validation of key metabolites, we characterized the metabolomic profile of human breast tumors and uncovered intrinsic metabolite signatures in these tumors. Importantly, the oncometabolite, 2-hydroxyglutarate (2HG), accumulated in a subset of tumors and human breast cancer cell lines. 2HG reached millimolar concentrations comparable to those in isocitrate dehydrogenase (IDH)-mutant gliomas, despite the absence of IDH mutations. Instead, we discovered a significant association between increased 2HG levels and MYC pathway activation in breast cancer, which was corroborated in human mammary epithelial and breast cancer cells with inducible MYC overexpression and knockdown. Further analyses showed a global increase of DNA methylation in 2HG-high tumors and identified a poor survival tumor subtype with distinct DNA methylation, high tissue 2HG, and heightened occurrence in African-American patients. Tumors of this subtype had a stem cell-like transcriptional signature with WNT and MYC pathway activation. These tumors over-expressed glutaminase, suggesting a functional relationship between glutamine and 2HG metabolism in breast cancer. Accordingly, 13C-labeled glutamine was metabolized into 2HG in cells with aberrant 2HG accumulation, whereas pharmacologic and siRNA-mediated inhibition of glutaminase markedly reduced 2HG. Our findings highlight 2HG as a candidate breast cancer oncometabolite associated with MYC activation and poor prognosis.

Citation Format: Prachi Mishra. Aberrant accumulation of 2-hydroxyglutarate in human breast cancer with myc activation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2952. doi:10.1158/1538-7445.AM2014-2952
Abstract 2955: Trail-R2: A death receptor turns malignant upon nuclear localization
Authors: Kalthoff Holger , Haselmann Verena , Kurz Alexandra , Bertsch Uwe , Huebner Sebastian , Fritsche Hendrik , Hauser Charlotte , Schem Christian , Tower Rob , Heilmann Thorsten , Tiwari Sanjay , Glüer Claus C. , Trauzold Anna
Published: May 2015

High intracellular expression of death receptor TRAIL-R2 correlates with poor prognosis for different tumor entities and thus suggests tumor-promoting activity of intracellular TRAIL-R2. We demonstrate that TRAIL-R2 interacts with the core Microprocessor components Drosha and DGCR8 and the associated regulatory proteins p68, hnRNPA1, NF45 and NF90 in the nucleus. Knockdown of TRAIL-R2 enhances Drosha-mediated processing of pri-let-7 resulting in increased levels of mature let-7, reduced expression of let-7-targets Lin28B and HMGA2 and inhibition of cell proliferation. In contrast, high abundance of nuclear TRAIL-R2, often detected in pancreatic cancer, correlates with enhanced expression of HMGA2 and dictates worse prognosis. Importantly, knockdown of TRAIL-R2 inhibits pancreatic tumor growth in an orthotopic xenotransplantation mouse model and reduced nuclear levels of TRAIL-R2 accompany differentiation of pancreatic epithelial cells in vitro. In conclusion, we define a novel function of nuclear TRAIL death receptor contributing to malignancy by inhibition of let-7-maturation (Haselmann et al., Gastroenterology epub ahead of print).

In extension to our work on pancreatic cancer we further show nuclear TRAIL-R2 functions to be of relevance in breast cancer bone metastasis. Stably shRNA- transfected clones of MDAMB231 cells revealed metastatic lesions in only 2/12 mice upon TRAIL-R2 knock-down, whereas TRAIL-R1 and control knock-down clones exhibited multiple metastases throughout the groups of 12 mice each. Under in vitro conditions some decreased apoptosis rate was observed in both TRAIL-R knock-down clonal populations compared to the controls upon TRAIL treatment. Preliminary results suggest Mesenchymal-Epithelial-Transition (as indicated by increased E-Cadherin expression in TRAIL-R2 knock-down cells) as a mechanism for reduced metastasis.

In summary, we show nuclear death receptor TRAIL-R2 to significantly contribute to malignant progression in two different pre-clinical tumor models. Thus, targeted intervention to prevent nuclear localization may serve as a novel therapeutic strategy.

Supported by DFG (TR 1063/2-1 and TR 1063/3-1 - SKELMET FOR 1586).

Citation Format: Holger Kalthoff, Verena Haselmann, Alexandra Kurz, Uwe Bertsch, Sebastian Huebner, Hendrik Fritsche, Charlotte Hauser, Christian Schem, Rob Tower, Thorsten Heilmann, Sanjay Tiwari, Claus C. Glüer, Anna Trauzold. Trail-R2: A death receptor turns malignant upon nuclear localization. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2955. doi:10.1158/1538-7445.AM2014-2955
Abstract 2960: Identification of Runx3 as a gatekeeper of lung adenocarcinoma
Authors: Lee You-Soub , Jang Ju-Won , Chi Xin-Zi , Ito Yoshiaki , Bae Suk-Chul
Published: May 2015

It is thought that SP-C/CC10 double positive cells, which normally contribute to the renewal of lung epithelial cells, are the origin adenocarcinoma (ADC) of the lung. The present study shows that postnatal disruption of Runx3 in the mouse lung results in dedifferentiation of bronchiolar epithelial cells into SP-C/CC10 double positive cells. The double positive cells differentiate into SP-C single positive cells and adenoma (median survival, longer than 1 year). When Adenovirus-Cre was infected, LSL-K-RasG12D mice induced ADC in prolonged latency (median survival, 220 days) and Runx3f/f/LSL-K-RasG12D mice rapidly induced ADC (median survival, 79 days), indicating a strong tumor suppressor activity of Runx3. When Cre was activated in a limited number of cells through a leaky activation of Cretm/ERT in the absence of tamoxifen, K-RasLSL-G12D/+/Cretm/ERT mice did not induce lung ADC. In contrast, simultaneous inactivation of Runx3 and activation of K-Ras (Runx3f/f/K-RasLSL-G12D/+/Cretm/ERT) induced lung ADC with striking morphological similarities to human lung ADC in all mice (median survival, 48 days after birth). We also found that Runx3 forms a complex with BRD2 (a relative of TAF250) in a K-Ras activity-dependent manner and the complex transiently induces p14ARF and p21. When K-Ras was constitutively activated, the Runx3-BRD2 complex was maintained for long time and the expressions of p14ARF and p21 was continued. Disruption of the Runx3-BRD2 complex abolished expression of these two genes. These results suggest that cells recognize oncogenic K-Ras through a monitoring system composed of Runx3-BRD2 complex and Runx3-inactivation leads to abrogation of the monitoring system as well as dedifferentiation of lung epithelial cells.

Citation Format: You-Soub Lee, Ju-Won Jang, Xin-Zi Chi, Yoshiaki Ito, Suk-Chul Bae. Identification of Runx3 as a gatekeeper of lung adenocarcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2960. doi:10.1158/1538-7445.AM2014-2960
Abstract 2979: Effects of VEGF inhibition on skin ulcer induced by administration of cytotoxic anticancer drugs
Authors: Shimoyama Tatsu , Ogura Kiyoshi , Kanemasa Yuusuke , Yamaguti Shigeo , Sasaki Eisaku , Omuro Yasushi , Sawada Takeshi , Koizumi Fumiaki , Maeda Yoshiharu
Published: May 2015

Introduction: An accidental extravasation of vesicant drugs-containing chemotherapy leads to skin ulcer, necrosis and severe tissue destruction.

The clinical evidences that VEGF inhibition suppresses tumorigenesis via inhibiting angiogenesis and causes delaying wound repair have been accumulated. We observed the cases that simultaneous administration of anti-human VEGF antibody, Bevacizumab, avoided critical skin ulcer which should be caused by extravasation of cytotoxic drug in the colorectal cancer combination chemotherapy. Therefore, we examined effects of VEGF or anti-VEGF-antibody and angiogenesis inhibitor on skin ulcer caused by administration of anticancer drug in a mouse model.

Methods: Experiments were performed in accordance with the United Kingdom Coordinating Committee on Cancer Research Guidelines for the welfare of animals in experimental neoplasia. Subcutaneous injections of doxorubicin (0.2mg/0.2ml of saline) in mice induced dose-dependent ulcerations under general anesthesia. The ulcers reached maximal size at 2-3 weeks following doxorubicin administration and were completely healed by 9 weeks. Effects of co-administration of test drugs on the area of the skin ulcer caused by administration of Adriamycin, were compared with control. Bevacizumab is anti-human VEGF antibody, it has no reactivity with mouse VEGF. An anti-mouse VEGF antibody was used alternatively.

Results: VEGF (5μg) increased the skin ulcer size up to 150%, and the healing time was increased to 11 weeks. Anti-VEGF antibody (50μg) and suramin reduced the maximum ulcer size (50%), and the healing time was reduced to 6 weeks.

Hydrocortisone (100μg) slightly reduced the skin ulcer size and the healing time (8 week).

Conclusion: VEGF aggravated skin ulcer caused by the administration of the Adriamycin. Anti-VEGF antibody and angiogenesis inhibitor, suramin, reduced skin ulcer caused by the administration of the Adriamycin.

Discussion: Inhibition of VEGF signaling and/or anti-angiogenesis were suggested to reduce skin ulcer caused by the Adriamycin. Anti-human VEGF antibody, Bevacizumab was suggested to be an effective antidote for skin ulcer and necrosis by extravasation of anticancer drugs and had potential for clinical use.

Citation Format: Tatsu Shimoyama, Kiyoshi Ogura, Yuusuke Kanemasa, Shigeo Yamaguti, Eisaku Sasaki, Yasushi Omuro, Takeshi Sawada, Fumiaki Koizumi, Yoshiharu Maeda. Effects of VEGF inhibition on skin ulcer induced by administration of cytotoxic anticancer drugs. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2979. doi:10.1158/1538-7445.AM2014-2979
Abstract 2982: Macrophages modulate adaptive resistance to anti-angiogenic therapy
Authors: Dalton Heather J. , Pradeep Sunila , Armaiz-Pena Guillermo N. , Previs Rebecca , Davis Ashley , Rupaimoole Rajesha , Zand Behrouz , Hailemichael Yared , Overwijk Willem W. , Lopez-Berestein Gabriel , Sood Anil K.
Published: May 2015

Targeted anti-angiogenic therapies were a highly anticipated addition to cancer treatment, but their clinical use has been tempered by the development of resistance. To understand the role of immune cells in potentially mediating such resistance, we carried out systematic immune cell profiling in a syngeneic ovarian cancer mouse model following treatment with the B20 anti-VEGF antibody. Following injection of luciferase-labeled cancer cells and initiation of treatment, mice (n=8/group) were divided into B20-sensitive and resistant groups based on longitudinal bioluminescence imaging of tumor burden. Immune cell profiling confirmed a dramatic increase in macrophages with emergence of resistance to B20. Using the syngeneic model, resistance to B20 was documented with bioluminescence imaging as an increase in tumor burden in mice with previously stable disease. Zoledronic acid, a macrophage-depleting bisphosphonate, was then added to B20 treatment. Restoration of sensitivity to B20 with the addition of zoledronic acid was demonstrated by a 68% prolongation of survival in this treatment group as compared to those receiving B20 alone (p<0.0001). Zoledronic acid in combination with the VEGF antibody, bevacizumab, significantly reduced both tumor size and nodules when compared to either drug alone in additional orthotopic models of ovarian cancer. CD68 staining confirmed significantly reduced macrophage numbers in tumor samples following treatment with zoledronic acid. In vitro immunofluorescence imaging of macrophages following prolonged exposure to anti-VEGF therapy showed downregulation of VEGF receptors compared to short-term exposure, suggesting a possible mechanism for their persistence in an anti-VEGF resistant microenvironment. Collectively, these data demonstrate a novel role for macrophages in resistance to anti-VEGF therapy and offer a new therapeutic strategy to overcome this problem with important translational implications.

Citation Format: Heather J. Dalton, Sunila Pradeep, Guillermo N. Armaiz-Pena, Rebecca Previs, Ashley Davis, Rajesha Rupaimoole, Behrouz Zand, Yared Hailemichael, Willem W. Overwijk, Gabriel Lopez-Berestein, Anil K. Sood. Macrophages modulate adaptive resistance to anti-angiogenic therapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2982. doi:10.1158/1538-7445.AM2014-2982
Abstract 299: Circulating microRNAs in association with colorectal neoplasia
Authors: Adams Scott V. , Newcomb Polly A. , Burnett-Hartman Andrea N. , Upton Melissa P. , Zhu Lee-Ching , Mandelson Margaret , Potter John D. , Makar Karen W.
Published: May 2015

Purpose: MicroRNAs (miRNAs) are non-coding regulatory RNAs that are stable in circulation and implicated in the etiology of many cancers including colorectal cancer (CRC). In this study we investigated whether candidate miRNAs could serve as blood-based biomarkers of colorectal adenoma.

Methods: We conducted a colonoscopy-based case-control study of men and women ages 50-79; this report includes data from 48 polyp-free controls, 43 advanced adenoma, 73 non-advanced adenomas, and 8 CRC cases. We selected 12 miRNA candidates that are highly expressed in adenoma tissue and have low expression in blood cells, in addition to miRNAs previously reported as biomarkers of adenoma. miRNAs were extracted from stored plasma samples, and copy number assessed with qRT-PCR. Odds ratios (ORs) and area-under-the-curve (AUC) from receiver-operator characteristic curves were estimated to quantify the association between plasma copy-number of these candidate miRNAs and each case group.

Results: No miRNA transcripts were associated with risk of adenoma or advanced adenomas, or with an AUC significantly above 0.5 that would indicate usefulness in discriminating either category of adenoma cases from controls. In contrast, statistically significant and strong associations (ORs>5) with CRC were observed for 6 miRNA candidates, with corresponding AUCs significantly greater than 0.5.

Conclusions: Our results suggest that these candidate miRNAs, assayed with qRT-PCR, are unlikely to have clinical utility as blood-based screening biomarkers of adenomas. However, strong associations were observed with CRC. Circulating miRNAs may therefore have promise as potential early detection biomarkers to augment current CRC screening methods, but an optimal screening biomarker would detect pre-malignant colorectal adenomas as well as frank CRC.

Citation Format: Scott V. Adams, Polly A. Newcomb, Andrea N. Burnett-Hartman, Melissa P. Upton, Lee-Ching Zhu, Margaret Mandelson, John D. Potter, Karen W. Makar. Circulating microRNAs in association with colorectal neoplasia. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 299. doi:10.1158/1538-7445.AM2014-299
Abstract 2996: Sunitinib withdrawal uncovers complementary stromal- and tumor-mediated mechanisms of resistance and rebound growth in metastatic mouse models
Authors: Mastri Michalis , Tracz Amanda , Lee Christina R. , Deveci Derya , Ebos John M. L.
Published: May 2015

Background: Despite the clinical approval of VEGF pathway targeted agents in the treatment of late-stage metastatic disease, sustained benefits are not seen in the majority of patients, and eventual relapse occurs. Understanding mechanisms of intrinsic and acquired drug resistance has taken on increasing importance as both host- and tumor-mediated pathways may contribute to treatment failure. However, few studies have aimed to assess resistance in clinically-relevant spontaneous metastatic disease after surgical resection of the primary tumor.

Methods: Here we describe the derivation of spontaneous metastatic human kidney, breast, and melanoma cell lines following long-term in vivo sunitinib treatment. Re-exposure of selected tumor and stromal cells to drug in vitro for extended periods allowed evaluation of reversible and irreversible gene expression changes. Cells were implanted orthotopically and then surgically removed to assess primary and metastatic growth potential following treatment cessation.

Results: Our results show that metastatic sunitinib-resistant cells retained treatment sensitivity when re-implanted orthotopically regardless of in vitro drug exposure conditions, suggesting a predominant host-mediated role in treatment failure. However, sunitinib treatment withdrawal elicited significant increases in tumor growth and metastatic potential, a finding which was enhanced when non-tumor bearing mice were ‘conditioned’ with drug prior to i.v. tumor cell inoculation. Parallel studies in vitro show increased proliferation and migration following therapy removal. Results from gene and protein expression analysis of cells in different sunitinib treatment conditions will be presented showing that coordinated tumor and host reactions can contribute to changes in metastatic phenotype upon therapy removal.

Conclusions: Taken together, clinically relevant models of drug-resistant spontaneous metastatic disease may have the potential to distinguish tumor- and stromal-responses to treatment that can alter in vivo disease progression both on (and off) therapy.

Citation Format: Michalis Mastri, Amanda Tracz, Christina R. Lee, Derya Deveci, John M. L. Ebos. Sunitinib withdrawal uncovers complementary stromal- and tumor-mediated mechanisms of resistance and rebound growth in metastatic mouse models. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2996. doi:10.1158/1538-7445.AM2014-2996
Abstract 2998: Akt-activated endothelium constitute the niche for residual disease and resistance to bevacizumab in ovarian cancer
Authors: Guerrouahen Bella Samia , Pasquier Jennifer , Kaoud Nadine Abou , Beauchamp Marie-Claude , Maleki Mahtab , Ghiabi Pegah , Lis Raphael , Saleh Ahmed , Gotlieb Walter H. , Rafii Shahin , Rafii Arash
Published: May 2015

Ovarian cancer is the second leading cause of cancer-related death in women worldwide. Despite optimal cytoreduction and adequate adjuvant therapies, initial tumor response is often followed by relapse suggesting the existence of a tumor niche. Targeted therapies have been evaluated in ovarian cancer to overcome resistant disease. Among them anti-angiogenic therapies inhibit new blood vessel growth, induce endothelial cell apoptosis, and block the incorporation of haematopoietic and endothelial progenitor cells into new blood vessels. Despite in vitro and in vivo successes antivascular therapy with bevacizumab targeting VEGF has limited efficacy in ovarian cancer. The precise molecular mechanisms underlying clinical resistance to anti-VEGF therapies are not yet well understood. Among them tumor and stromal heterogeneity might determine the treatment outcomes. The present study investigates whether abnormalities in the tumor endothelium may contribute to treatment resistance to bevacizumab and promote a residual microscopic disease. Here we showed that ovarian cancer cells (OCC) activate akt phosphorylation in endothelial cells inducing resistance to bevacizumab leading to an autocrine loop based on FGF2 secretion. Altogether our results point out the role of an activated endothelium in the resistance to bevacizumab and in the constitution of a niche for a residual disease.

Citation Format: Bella Samia Guerrouahen, Jennifer Pasquier, Nadine Abou Kaoud, Marie-Claude Beauchamp, Mahtab Maleki, Pegah Ghiabi, Raphael Lis, Ahmed Saleh, Walter H. Gotlieb, Shahin Rafii, Arash Rafii. Akt-activated endothelium constitute the niche for residual disease and resistance to bevacizumab in ovarian cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2998. doi:10.1158/1538-7445.AM2014-2998
Abstract 3009: Membrane pseudokinase PTK7 regulates metastasis
Authors: Golubkov Vladislav , Zhang Yong , Prigozhina Natalie , Hoffman Robert M. , Strongin Alex
Published: May 2015

Studies by others indicate that the membrane pseudokinase 7 (PTK7) regulates canonical and non-canonical Wnt pathways and controls orientation of cells in a tissue plane (planar cell polarity, PCP). There is still no clear understanding of the PTK7 role in cancer: Is it pro-tumorigenic or anti-tumorigenic? Our live cell imaging and cell invasion studies suggest that full-length PTK7 expressed in HT1080 fibrosarcoma cells inhibits directed cell motility, lamellipodia polarization and cell invasion. Using the fluorescence imaging we demonstrated that the expression of full-length PTK7 in HT1080-RFP cells in nude mice significantly reduces lung colonization (metastasis). The pro-invasive membrane type-1 matrix metalloprotease (MT1-MMP/MMP-14) coupled with an ADAM/ADAMTS family member(s) directly cleave PTK7 at the cell surface and reverse the inhibitory anti-invasive signal of full-length PTK7. Ectodomain proteolysis was a prerequisite for the intramembrane cleavage of the residual fragments of PTK7 by γ-secretase. The resulting C-terminal PTK7 fragment translocated to the cell nucleus. To identify the molecular mechanisms downstream of PTK7 proteolysis, we used genome-wide transcriptional profiling and kinome analysis. Full-length PTK7 and the PTK7 mutants representing the cleaved PTK7 forms differentially regulated the expression of multiple genes and induced signaling pathways associated with cell movement, Wnt signaling and cancer. We believe that the regulation of PTK7 proteolysis opens new possibilities to control Wnt signaling, cancer cell invasion and metastasis.

Citation Format: Vladislav Golubkov, Yong Zhang, Natalie Prigozhina, Robert M. Hoffman, Alex Strongin. Membrane pseudokinase PTK7 regulates metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3009. doi:10.1158/1538-7445.AM2014-3009
Abstract 3014: Hyaluronan-mediated motility receptor maintains stemness and tumorigenic potential of glioblastoma stem cells
Authors: Tilghman Jessica , Laterra John , Ying Mingyao
Published: May 2015

Glioblastoma (GBM) stem cells (GSCs) are a subpopulation of tumor cells that display stem-like characteristics (stemness) and play unique roles in tumor propagation, therapeutic resistance and tumor recurrence. It is becoming increasingly important to identify novel therapeutic targets in GSC for anti-GBM therapies. Here, we demonstrate that hyaluronan-mediated motility receptor (HMMR) is hyper-expressed in GBM tumors and supports the self-renewal and tumorigenic potential of GSCs. HMMR silencing impairs GSC self-renewal and inhibits the expression of GSC markers and regulators. HMMR silencing suppresses GSC-derived tumor growth and extends the survival of mice bearing GSC xenografts. HMMR overexpression promotes GSC self-renewal and intracranial tumor propagation. In human GBM tumor specimens, HMMR expression is positively correlated with the expression of cell-stemness-associated markers and regulators. Our findings identify HMMR as a potential therapeutic target for inhibiting GSCs, suggesting therapeutic applications against GBM.

Citation Format: Jessica Tilghman, John Laterra, Mingyao Ying. Hyaluronan-mediated motility receptor maintains stemness and tumorigenic potential of glioblastoma stem cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3014. doi:10.1158/1538-7445.AM2014-3014
Abstract 3019: Aberrant NF-κB and Notch pathways promote CD133+ cancer stem cells in human primary cutaneous squamous cell carcinoma
Authors: Quan Xinxin , Voong Nga , Chen Weiping , Coupar Jamie , Lee Steven , Petersen David W. , Edelman Daniel C. , Meltzer Paul S. , Montemarano Andrew , Braun Martin , Vogel Jonathan , Waes Carter Van , Chen Zhong
Published: May 2015

The cancer stem cell (CSC) subpopulation has been implicated in inducing tumorigenesis and drug resistance, however, the unique gene program and regulatory signaling that contribute to the CSC phenotypes in human cutaneous squamous cell carcinoma (hcSCC) have not been defined. In this study, a newly improved cell sorting method was developed using a panel of multiple cell surface markers to isolate the small percentage of CD133+ cell population enriched for CSC in primary hcSCC specimens. These cells exhibited CSC features including enhanced spheroid formation in vitro and tumor formation in vivo. Distinct gene expression signatures of the CD133+ subset were profiled by comparing CD133+ CSC with CD133- cancer cells using microarray, which revealed that CD133+ cells expressed enriched stem cell and cancer-related gene programs. In the CD133+ subset, 80 differentially expressed stem cell genes were identified, with an additional set of 69 altered genes enriched in key regulatory pathways, including Notch, NF-κB, Wnt, EMT, and STAT signaling, using Gene Ontology (GO) and Ingenuity Pathway Analysis (IPA). The expression patterns of combined signature genes of CSC and the key regulatory pathways were validated with Nanostring gene expression assay in independent tumor samples. Notch and NF-κB signaling emerged as important pathways. Inhibitors or siRNA knockdown of Notch1/2 and IKKα inhibited NF-κB activity and altered CSC phenotypes, including percentage of CD133+ cells, colony and spheroid formation. Elevated NF-κB signaling was observed in CSCs in the tumor tissues, where immunofluorescent staining showed co-localization of CD133+ and molecules of NF-κB pathway in SCC tumor specimens. Our data support the importance of aberrant NF-κB and Notch signaling in promoting CSC gene program and biologic functions, which could represent predictive diagnostic and prognostic parameters and potential targets for skin cancer prevention and treatment.

Supported by NIDCD intramural projects ZIA-DC-000016, 73 and 74.

Citation Format: Xinxin Quan, Nga Voong, Weiping Chen, Jamie Coupar, Steven Lee, David W. Petersen, Daniel C. Edelman, Paul S. Meltzer, Andrew Montemarano, Martin Braun, Jonathan Vogel, Carter Van Waes, Zhong Chen. Aberrant NF-κB and Notch pathways promote CD133+ cancer stem cells in human primary cutaneous squamous cell carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3019. doi:10.1158/1538-7445.AM2014-3019
Abstract 3025: HER2/Stat3 signaling mediated radioresistance in U87 glioma cancer cells through suppressed apoptosis and enhanced glycolysis
Authors: Qin Lili , Fan Ming , Li Jian Jian
Published: May 2015

GBM is the most common and aggressive malignant primary brain tumor, and the prognosis for GBM patients remains poor. Radiotherapy continues to play a central role in the management of brain tumors. Even though the advances of radiotherapy strategies and techniques, frequent failure of radiotherapy made GBM a disease difficult to be treated. GBM cancer stem cells (CSCs) are reported to be responsible for resistance to chemo- and radiotherapy, and chemotherapy and radiotherapy resistant GBM CSCs have been isolated from GBM. However, the mechanisms of radioresistance of glioma cells are still elucidative. In this study, we investigated the role of HER2-Stat3 signaling pathway in radioresistance using human glioma cell line U87. We found that long-term therapeutic dose of fragmented irradiation induces repopulation of human glioma U87 cells with increased number of CD133+/HER2+ stem-like cells. FIR-surviving CD133+/HER2+ U87 cells have coactivation of HER2 and Stat3 and increased cell proliferation and invasion abilities. More importantly, we found that U87-FIR cells have lower level of mitochondria metabolism and ROS level, and higher mitochondrial membrane potential, while 5Gy single dose radiation induces increased mitochondria function. Furthermore, U87 cell injection derived xenograph tumor also has increased mitochondrial membrane potential and decreased mitochondria function after radiation. These results suggest that the radioresistance of GBM CSCs possibly due to the suppressed apoptosis and enhanced glycolysis mediated by HER2/STAT3 pathway.

Citation Format: Lili Qin, Ming Fan, Jian Jian Li. HER2/Stat3 signaling mediated radioresistance in U87 glioma cancer cells through suppressed apoptosis and enhanced glycolysis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3025. doi:10.1158/1538-7445.AM2014-3025
Abstract 3031: HMGA2 promotes invasion and stemness in glioblastoma
Authors: Kaur Harpreet , Hütt Marianne , Mao Xing-gang , Orr Brent A. , Eberhart Charles G. , Raabe Eric H.
Published: May 2015

Glioblastoma Multiforme (GBM) causes the majority of brain tumor-related deaths in the United States. The high invasiveness of GBM prevents complete surgical resection, allowing tumor recurrence. The lack of curative treatment highlights a dire need to develop specific targeted therapeutics. Identifying and targeting novel molecular markers in glioma stem-like cells (GSCs), one of the major causes of tumor invasion and recurrence, could lead to development of better therapies. HMGA2, a non-histone transcriptional modulator, is a regulator of normal and cancer stem cells. The significance of HMGA2 as a potential therapeutic target in GBM has not been investigated. To elucidate the role of HMGA2 in GBM, we have used a combination of in vitro and in vivo techniques. We found increased HMGA2 expression in the mesenchymal subgroup of GBM tumors in the The Cancer Genome Atlas (TCGA) database and in a subset of primary human GBM tumors. HMGA2 is expressed in multiple patient-derived GBM neurosphere lines with increased expression in CD133+ neurospheres compared to CD133- neurospheres. Lentiviral short hairpin RNA (shRNA)-mediated reduction of HMGA2 significantly inhibited invasion of GBM neurosphere lines (040821, 62% reduction with HMGA2 shRNA vs. control shRNA, P<0.001) in transwell invasion assays. Conversely, lentiviral-mediated overexpression of HMGA2 in GBM neurosphere lines increased invasion (GBM1 and 040821, 100-130% increase with HMGA2 overexpression vs. control vector, P<0.001) in transwell invasion assays. In addition, overexpression of HMGA2 increased clonogenicity of GBM neurosphere lines in vitro in soft agar and methylcellulose colony formation assays (40-60% increase with HMGA2 overexpression vs. control vector, P<0.001). Importantly, log-rank analysis of Kaplan-Meier plots showed increased survival of mice injected with GBM neurosphere lines transduced with HMGA2 shRNA compared to control shRNA (P<0.05) in an in vivo, orthotopic, intracranial mouse xenograft model. To elucidate the molecular mechanism by which HMGA2 promotes invasion and stemness in GBM, we performed mRNA expression profiling on GBM neurosphere lines lentivirally transduced to express HMGA2 or empty vector control. We found increased CD44 expression in HMGA2-overexpressing GBM neurosphere lines compared to control. Together, our results suggest an oncogenic role of HMGA2 in promoting GBM tumorigenicity by increasing invasiveness and a stem cell-like state, thereby suggesting that HMGA2 is a potential therapeutic target in GBM.

Citation Format: Harpreet Kaur, Marianne Hütt, Xing-gang Mao, Brent A. Orr, Charles G. Eberhart, Eric H. Raabe. HMGA2 promotes invasion and stemness in glioblastoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3031. doi:10.1158/1538-7445.AM2014-3031
Abstract 3036: Basal stem cells contribute to squamous cell carcinomas in the oral cavity
Authors: Tang Xiao-Han , Scognamiglio Theresa , Gudas Lorraine
Published: May 2015

The cells of origin of oral cavity squamous cell carcinoma (OCSCC) are unknown. We used a cell lineage tracing approach (adult K14-CreERTAM; ROSA 26 mice transiently treated with tamoxifen) to identify and track normal epithelial stem cells (SCs) in mouse tongues by X-gal staining and to determine if these cells become neoplastically transformed by treatment with a carcinogen, 4-nitroquinoline 1-oxide (4-NQO). Here we show that in normal tongue epithelia, X-gal(+) cells formed thin columns throughout the entire epithelium 12 weeks after tamoxifen treatment, indicating that the basal layer contains long lived SCs that produce progeny by asymmetric division to maintain homeostasis. Carcinogen treatment results in a ∼ 10 fold reduction in the total number of X-gal(+) clonal cell populations and horizontal expansion of X-gal(+) clonal cell columns, a pattern consistent with symmetric division of some SCs. Finally, X-gal(+) SCs are present in papillomas and invasive OCSCCs, and these long-lived X-gal(+) SCs are the cells of origin of these tumors. Moreover, the resulting 4-NQO induced tumors are multi-clonal. These findings provide insights into the identity of the initiating cells of oral cancer.

Citation Format: Xiao-Han Tang, Theresa Scognamiglio, Lorraine Gudas. Basal stem cells contribute to squamous cell carcinomas in the oral cavity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3036. doi:10.1158/1538-7445.AM2014-3036
Abstract 3037: Adipokines modulate human mammary stem cell self-renewal through mTOR
Authors: Esper Ray , Michael Dame , Djuric Zora , Smith William , Wicha Max , Brenner Dean
Published: May 2015

Rationale: Excess visceral adiposity is associated with an increased incidence of a variety of human ailments, including cancer. We tested the hypothesis that adipose-derived factors drive normal mammary stem cell self-renewal.

Methods: Visceral adipose tissue explants from obese F344 rats and cultured mouse 3T3-L1 adipocytes were grown with serum-free media for 48 hours. Primary human mammary epithelial cells, MCF10A, SUM149 and MCF7 cells were exposed to rhleptin (500 ng/ml), or adipocyte conditioned media and expanded in a non-adherent sphere forming assay for 10 days. Spheres were counted and size was quantified in Image J. Adipokine concentrations were assayed with the Proteome Profiler Adipokine Array. Other cultures were pre-treated with mTOR inhibitors rapamycin (100 nM) or everolimus (100 nM) for 2 hours prior to exposure to rhleptin or adipocyte conditioned media for 2 hours. S6 protein phosphorylation was quantified from Western blots.

Results: Data shown in Table 1 suggest that conditioned media from adipose tissue and from 3T3-L1 adipocytes increase human mammary stem cell self-renewal by 103% and 189%, respectively, whereas rhleptin increases stem cell self-renewal by 37%. Blockade of leptin activity with neutralizing antibodies or chimeric soluble receptors reduced the adipocyte conditioned media's stimulation of mammary epithelial cell self-renewal by 10-15%. Media conditioned by the mouse 3T3-L1 adipocytes or primary rat visceral adipose explants increased pS6 protein by 170% in MCF10A cells. mTOR inhibitors reduced rhleptin and adipocyte conditioned media stimulation of self-renewal in MCF10A and normal human mammary stem cells by 78-85%.

Conclusion: Adipocyte secreted factors and rhleptin promote increased mammary epithelial cell self-renewal through a process involving the activation of mTOR. Leptin contributes to a small fraction of the activity in adipocyte conditioned media, and is sufficient but not required for mammary stem cell self-renewal.

Change in stem cell self-renewalrhLeptin3T3-L1 Adipocyte Conditioned MediaRat Adipose Tissue Conditioned MediaBaseline # Spheres% Change (± SEM)P Value% Change (± SEM)P Value% Change (± SEM)P ValuePrimary human organoids19737 ± 7.005104 ± 20.006190 ± 26.001MCF-10A cells28834 ± 16.043320 ± 32.002389 ± 27.002MCF-7 cells57638 ± 9.007142 ± 15.001262 ± 40.006SUM149 cells95435 ± 6.09174 ± 20.012167 ± 21.003

Citation Format: Ray Esper, Dame Michael, Zora Djuric, William Smith, Max Wicha, Dean Brenner. Adipokines modulate human mammary stem cell self-renewal through mTOR. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3037. doi:10.1158/1538-7445.AM2014-3037