bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 3343: Podophyllotoxin acetate (PA) enhancing γ-ionizing radiation-induced apoptosis via the ROS/p38/caspase pathway
Authors: Choi Jae Yeon , Hwang Sang-Gu , Um Hong-Duck , Park Jong Kuk 
Published: August 2015

Abstract
To develop a new radiosensitizer candidate capable of increasing the efficiency of radiotherapy and to investigate the underlying molecular mechanisms in vitro and in vivo. To develop a new radiosensitizer against non-small cell lung cancer cells, we screened a natural product library for growth-inhibitory compounds. Podophyllotoxin acetate (PA) was found to be cytotoxic toward NCI-H460 cells, and its IC50 value was determined. The radiosensitizer effects of PA were tested at its IC50 value in clonogenic and cell-counting assays. The intracellular mechanism underlying this effect was determined by immunoblotting and by measuring propidium iodide uptake and ROS generation. The radiosensitizer activity of PA in vivo was tested in nude mice by treating with PA and IR, and measuring tumor volume and assessing apoptosis. PA, tested at its experimentally determined IC50 value (12 nM), enhanced γ-ionizing radiation (IR)-induced death of NCI-H460 cells by increasing apoptosis, yielding a mean calculated dose-enhancement ratio of 3.8. Combination with PA and IR also increased the production of reactive oxygen species (ROS), which subsequently induced phosphorylation of p38, suppressed phosphorylation of ERK, and activated caspase-3, -8, and -9. Notably, inhibition of ROS production prevented p38 phosphorylation, and inhibition of ROS production or p38 activation blocked caspase activation and apoptosis. In a xenograft assay, combination with PA and IR delayed tumor growth by 11.4 days compared with controls, yielding an enhancement factor of 1.48. Collectively, these results indicate that PA functions as a radiosensitizer by enhancing apoptosis through activation of a ROS/p38/caspase pathway and suppression of ERK.
Citation Format: Jae Yeon Choi, Sang-Gu Hwang, Hong-Duck Um, Jong Kuk Park. Podophyllotoxin acetate (PA) enhancing γ-ionizing radiation-induced apoptosis via the ROS/p38/caspase pathway. [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 3343. doi:10.1158/1538-7445.AM2015-3343
Abstract 3347: Radiation-induced gastrointestinal (GI) syndrome as a function of age
Authors: Li Hongyan , Kucharavy Herman , Hajj Carla , Hua Guoqiang , Glass Ryan , Zeng Zhaoshi , Fuks Zvi , Paty Philip B. , Kolesnick Richard , Hubbard Karen , Haimovitz-Friedman Adriana 
Published: August 2015

Abstract
The incidence of cancer increases with age and is generally thought to be an age-related disease. In prior studies we model tumor response to radiation therapy (RT) by studying its effect on normal tissue damage. We showed that RT-induced gastrointestinal (GI) syndrome represents coupled damage to intestine's micovasculature and the parenchymal epithelial cells. In addition, we showed that 15Gy irradiation is a lethal dose 100 for C57Bl6 mice treated with whole body irradiation (WBI) as it induces apoptosis in endothelial cells (EC) and initiates the GI syndrome in the small intestine. Our objective is to determine whether the microvasculature and/or the cycling crypt base columnar cells (CBCs), the small intestine stem cells, in an aging population (29 months mice, approx. 69 years in humans) are more sensitive to radiation effects than in young adults (3 months mice, approx. 20 years old human) with regards to normal tissue toxicity.
Radiation-induced premature senescence and apoptosis were evaluated in EC and in CBCs in old mice versus young adult mice. Our results show enhanced endothelial apoptosis in crypts of older mice compared to young adult mice. There was a higher death rate in older versus young adult mice due to radiation-induced GI syndrome (90% vs 40% at 14Gy and 100% vs 60% at 15Gy). Crypt microcolony survival assays showed that 29 months-old mice had a lower number of regenerating crypts in all three doses tested (13Gy, 14Gy, 15Gy). In addition, there was an increase in CBC senescence in older mice compared to young adult mice. Therefore, microvasculature damage and an increase in CBCs apoptosis and senescence are the main events contributing to the enhanced rate of development of the RT-induced GI syndrome in the older mice. Ongoing studies are testing whether there is more senescence in the endothelial cells in older mice than in the mature adults, and if RT enhances senescence in these cells in older vs younger adult mice.
These studies will be extended to include animals with various cancer burdens to explore the role of age in the efficacy of radiation treatment.
Citation Format: Hongyan Li, Herman Kucharavy, Carla Hajj, Guoqiang Hua, Ryan Glass, Zhaoshi Zeng, Zvi Fuks, Philip B. Paty, Richard Kolesnick, Karen Hubbard, Adriana Haimovitz-Friedman. Radiation-induced gastrointestinal (GI) syndrome as a function of age. [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 3347. doi:10.1158/1538-7445.AM2015-3347
Abstract 3348: Tumor irradiation induced a phenotype change of monocytes to facilitate vascular regrowth
Authors: Deng Lei , Stafford Jason , Chernikova Sophia , Liu Shie-chau , Sun Jianguo , Brown J. Martin 
Published: August 2015

Abstract
We and others have previously shown that tumor irradiation mobilizes CD11b+ myeloid cells from bone marrow into the tumor thereby facilitating vascular regrowth and tumor recurrence. However, how these CD11b+ cells promote vasculature growth remains largely undefined. In this study, we found that CD11b+ cells in a 12Gy-irradiated U251 glioblastoma tumor model were largely Ly6g negative, suggesting that these cells are not in the granulocyte lineage, but rather are monocyte/macrophages (CD11b+Ly6g-). Interestingly, we found that the proportion of Ly6c+ monocytes in the irradiated tumor remained unchanged compared to that in the pre-irradiate tumor. However, the proportion of Ly6c- monocytes rose, driving the increase of total CD11b+ cells post-irradiation. Compared to Ly6c+ monocytes, Ly6c- cells in irradiated tumors were the major cells expressing VEGF. In vitro culture of murine bone marrow enriched Ly6c+ monocyte with colony stimulating factor-1 (CSF-1) downregulated Ly6c expression and increased in vitro angiogenic capability as demonstrated by the tube formation assay. Adding PLX3397, a CSF-1 receptor inhibitor to irradiation, which has been shown to delay tumor growth previously, decreased the Ly6c- monocytes more than the Ly6c+ monocytes. Given that we and others have previously shown that CSF-1 expression was increased in irradiated tumors, we conclude that tumor irradiation induced a phenotype change of monocytes from Ly6c+ to Ly6c- and that the latter, which are more pro-angiogenic, promote tumor vascular regrowth and recurrence post-irradiation.
Citation Format: Lei Deng, Jason Stafford, Sophia Chernikova, Shie-chau Liu, Jianguo Sun, J. Martin Brown. Tumor irradiation induced a phenotype change of monocytes to facilitate vascular regrowth. [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 3348. doi:10.1158/1538-7445.AM2015-3348
Abstract 3353: Prostate cancer microenvironment modulates macrophage phagocytosis
Authors: Weagel Evita G. , Anderson Nicholas B. , Meng Wei , Davis Josh , Robison Richard A. , O'Neill Kim L. 
Published: August 2015

Abstract
Macrophages play an important role in the body's immune system. There are two main phenotypes of macrophages, M1 and M2. M1 polarized macrophages participate in tumorcidal activity and pro-inflammatory responses. M2 macrophages perform anti-inflammatory responses and promote tissue repair, angiogenesis, and tumor growth. Macrophages within the vicinity of cancer cells may be influenced by the microenvironment and change their gene expression accordingly. Macrophages can express different cytokine profiles depending on their polarization state (M1 or M2). We investigated whether macrophages exposed to cancer cells demonstrate a M2 or M1 phenotype. We stimulated U937 cells with phorbol 12-myristate 13-acetate (PMA) for 24 hours to allow for adhesion and differentiation. We co-cultured PMA-stimulated U937 macrophages with PC3 and DU145 prostate cancer cell lines in a 1:1 ratio with a transpermeable membrane to allow for cell to cell contact and communication, and with PC3 and DU145 conditioned media for 48 hours. We isolated the RNA from the treated macrophages and performed qPCR to assess gene expression levels of the following cytokines: IL-10, a cytokine demonstrating a M2 phenotype was upregulated by 10 and 15 fold for PC3 and DU145 cells respectively and by 3 fold in both cell lines exposed to conditioned media. We also found a trend of downregulation with the cytokines IL-1, IL-12, and TNF - alpha, which also depict a M2 phenotype. We also assessed macrophage function by measuring engulfment by flow cytometry. Treated macrophages were allowed to phagocytose fluorescent microbeads for 1 hour. Flow cytometry analysis revealed that total bead engulfment decreased by up to 80% in macrophages treated with PC3 cells. Moreover, the population of macrophages that engulfed 3+ beads decreased significantly from both the cells and media treatments. Macrophages treated with DU145 cells and spent media also showed a similar trend to macrophages exposed to PC3 cells. The results show that macrophages exposed to PC3 and DU145 cancer cell lines polarized towards an M2 phenotype and could be important in the success of cancer within the microenvironment. Further research will reveal whether this process of a M2 polarization of macrophages is mediated by cytokines and cell vesicles or other factors.
Citation Format: Evita G. Weagel, Nicholas B. Anderson, Wei Meng, Josh Davis, Richard A. Robison, Kim L. O'Neill. Prostate cancer microenvironment modulates macrophage phagocytosis. [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 3353. doi:10.1158/1538-7445.AM2015-3353
Abstract 3361: CD73 expression on tumor-infiltrating breast cancer leukocytes
Authors: Buisseret Laurence , Garaud Soizic , Allard Bertrand , Cousineau Isabelle , Chouinard Guillaume , Sotiriou Christos , Willard-Gallo Karen , Stagg John 
Published: August 2015

Abstract
Recent studies have shown that CD73 could be a new promising target in breast cancer (BC). CD73 is a cell surface ecto-nucleotidase, expressed by both tumor cells and immune cells, that catalyses the hydrolysis of AMP into adenosine in the tumor microenvironment. Adenosine has immunosuppressive and tumor-promoting effects and is therefore implicated in the mechanism of tumor immune escape. High CD73 gene expression has recently been associated with a poor prognosis in triple negative BC.
While tumor expression of CD73 is well documented, expression of CD73 on tumor-infiltrating immune cells remains poorly characterized. We evaluated the expression of CD73 on immune cells present in fresh tissue homogenates (GentleMACS with no enzymatic digestion) from untreated primary breast tumors and compared to its expression to peripheral blood mononuclear cells (PBMC) from patients with breast cancer. In the peripheral blood, CD73 was found mostly expressed on CD4+ (mean percentage: 13.24±12.88%) and CD8+T cells (mean percentage: 40.78±19.42%) and a major subset of B cells (mean percentage: 51.93±21.83%). Analysis of fresh tumor tissues revealed that less than 25% of CD45+ tumor immune infiltrates express CD73 (mean percentage: 17.63± 5,1%) and was relatively similar to its expression on PBMC (mean percentage: 14.87± 9.5%). In the tumor immune infiltrates, B cells were the immune subset with the higher proportion of CD73+ cells (mean percentage: 53.27±14.63%) while the proportion of CD73+ was lower on tumor-infiltrating CD8+ T cells compared to CD8+ PBMC (p value: 0.022). Notably, we observed that CD73 expression was significantly higher on tumor-infiltrating NK cells and CD14+ myeloid cells compared to peripheral cells (p = 0.005 for NK cells, and p = 0.015 for CD14+ cells). Immunofluorescence analysis confirmed that CD73 is expressed by both tumor cells, CD45+ immune cells and stromal cells in breast cancer.
These results suggest that CD73 is differentially expressed on tumor-infiltrating leukocytes compared to PBMCs. Modulation of CD73 activity on tumor-infiltrating leukocytes may therefore contribute to the mechanism-of-action of anti-CD73 therapies.
Citation Format: Laurence Buisseret, Soizic Garaud, Bertrand Allard, Isabelle Cousineau, Guillaume Chouinard, Christos Sotiriou, Karen Willard-Gallo, John Stagg. CD73 expression on tumor-infiltrating breast cancer leukocytes. [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 3361. doi:10.1158/1538-7445.AM2015-3361
Abstract 3376: Ras activation in aberrant crypt foci is associated with decreased expression of cell cycle regulators and disruption of stromal homeostasis
Authors: Mo Allen , Horelik Nicole A. , Jackson Stephen , Devers Thomas J. , Rosenberg Daniel W. 
Published: August 2015

Abstract
Aberrant crypt foci (ACF) are the earliest detectable premalignant lesion within the colon. A majority of ACF harbor somatically acquired mutations to cancer-related genes. ACF may be an indicator for a colonic mucosa at-risk for cancer development, however only a small subset of ACF have the potential to progress to malignancy. We believe that the majority of ACF activate growth inhibitory programs that ultimately result in their growth arrest and regression. In order to begin to define the gene expression changes that occur within these early microscopic lesions and their underlying stroma, we have developed a novel method that combines laser capture micro-dissection with targeted RNA-seq analysis. In the following study, gene expression profiles of thirteen human ACF biopsy specimens harboring known oncogenic mutations (K-ras, B-raf, N-ras, and APC) were compared to matched normal mucosa. Two gene panels were used to assess the status of important cell regulatory pathways: an apoptosis panel comprised of 267 genes and a customized cell senescence panel consisting of 20 genes. In the apoptosis panel, the expression of 81 genes were differentially expressed in ACF compared to matched normal mucosa. Expression of HRK, a potent activator of apoptosis, was the most significantly down-regulated gene (6.75-fold, q &lt;0.01) in every ACF when compared to normal mucosa. Inactivation of HRK function occurs in a variety of tumor types, including prostate cancer, astrocytomas and lymphomas. ACF with mutations occurring within the MAP-K pathway (K-ras, B-raf, N-ras) showed strong activation of downstream ras-associated genes and down-regulation of cell cycle regulators (CDK4 (p = 0.01), CCNB1 (p = 0.04), CCNA2 (p = 0.01), and TP53 (p = 0.04)). Interestingly, these expression panels were distinct from ACF harboring somatic mutations to APC. Analysis of microdissected stroma directly underlying the aberrant crypt structures revealed 25 differentially expressed genes, with dysregulation of several inflammatory mediators (IL2, IL2RA, IL6, TGFB2, BMP4) and extracellular matrix remodeling targets (TIMP1, TIMP2). Our findings suggest that ras-activated ACF may cause significant changes in cell cycle regulation, as well as alterations in stromal extracellular matrix maintenance and inflammatory response.
Citation Format: Allen Mo, Nicole A. Horelik, Stephen Jackson, Thomas J. Devers, Daniel W. Rosenberg. Ras activation in aberrant crypt foci is associated with decreased expression of cell cycle regulators and disruption of stromal homeostasis. [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 3376. doi:10.1158/1538-7445.AM2015-3376
Abstract 3377: Co-spheroid analysis reveals attenuating effect of HS27A stroma cells on DLD1 colon carcinoma susceptibility to MEK kinase inhibitor trametinib
Authors: Hoffmann Claudia , Feger Daniel , Siedentopf Oliver , Weber Holger , Umber Sarah , Ehlert Jan E. 
Published: August 2015

Abstract
In cancer treatment, stroma-derived microenvironmental cues are suspected to exert an adversary impact on anti-cancer drug efficacy. In order to take such influences into account in cellular drug screening campaigns, we have set up a high-throughput-compatible co-spheroid model, enabling the analysis of various combinations of cancer and stroma cell lines. This assay system allows for cell analysis in a three-dimensional (3D) close-to-physiological environment with simultaneous detection of cancer and stroma cell viability based on differential luciferase cell-labelling. Our data revealed that growth characteristics strongly depend on the specific cell types combined. Stroma cells in contrast to tumor cells usually ceased to proliferate or even showed dramatic loss of viability possibly due to metabolic hijacking. We report on the optimization of the cellular test systems to ensure significant viable stroma cell counts during the drug testing phase. In such an optimized co-spheroid model of Firefly-luciferase labelled DLD-1 colon cancer cells with Renilla-luciferase labelled HS27A stroma cells, we identified the MEK kinase inhibitor Trametinib as a compound showing a 10-30fold attenuated potency as compared to the DLD-1 mono-spheroid model. Based on these results we suggest integrating optimized co-spheroid studies into early drug development to focus on compounds that remain active under microenvironmental conditions.
Citation Format: Claudia Hoffmann, Daniel Feger, Oliver Siedentopf, Holger Weber, Sarah Umber, Jan E. Ehlert. Co-spheroid analysis reveals attenuating effect of HS27A stroma cells on DLD1 colon carcinoma susceptibility to MEK kinase inhibitor trametinib. [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 3377. doi:10.1158/1538-7445.AM2015-3377
Abstract 338: Immunohistochemical expression of CD44/ERM complex proteins in penile carcinoma
Authors: de Andrade Juliana B. , Soares Fernando A. 
Published: August 2015

Abstract
Background: The loco-regional involvement is considered the main complication and cause of death in the natural history of penile carcinoma. Understanding the molecular processes that may be involved in metastatic dissemination would improve the prognostic tools to better evaluate the patients, avoiding the morbidity of unnecessary surgery. Some studies have emphasized the influence of cellular adhesion in the development of tumorigenesis and metastasis as the proteins of complex CD44/ERM (Ezrin/Radixin/Moesin). Therefore, this study aimed to analyze the expression of proteins CD44 and its variant CD44v6, Ezrin and Moesin in squamous cell penile carcinoma, correlating their expression with the clinical-pathological criteria.
Material and Methods: Eighty four patients were selected, retrospectively, undergoing surgery for squamous cell penile carcinoma at AC Camargo Cancer Center. The expression evaluation for CD44, CD44v6 Ezrin and Moesin was performed by immunohistochemistry using Ventana® equipment, subsequently analyzed by digital microscopy in Aperio® system. The immunoreactivity of each protein was categorized as positive and negative using a cut-off criteria established by the average percentage obtained.
Results: CD44 expression was present in 19 (22.6%) positive cases, CD44v6 in 50 (59.5%), Ezrin in 30 (35.7%) and Moesin in 53 (63.1%). It was observed that the loss of CD44 expression was significantly correlated with recurrence (p = 0.002) and with the glans invasion (p = 0.035); the positive expression of CD44v6 was significantly correlated with the tumor size (p = 0.009) and with recurrence (p = 0.018); the loss of Ezrin expression was significantly correlated with macroscopic invasion (p = 0.028) and with foreskin of invasion (p = 0.015); the positive expression of Moesin was significantly correlated with macroscopic invasion (p = 0.010) and the loss of its expression was significantly correlated with recurrence (p = 0.035). Disease-free survival was significantly influenced by CD44, CD44v6 and Moesin.
Conclusion: The expression of CD44, CD44v6, Ezrin and Moesin seems to significantly influence the prognostic factors of penile carcinoma and could be an important molecular marker in the identification of recurrence risk.
Citation Format: Juliana B. de Andrade, Fernando A. Soares. Immunohistochemical expression of CD44/ERM complex proteins in penile carcinoma. [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 338. doi:10.1158/1538-7445.AM2015-338
Abstract 3383: Correlation of mutations detected in liquid and tissue biopsies
Authors: White Douglas H. , Horejsh Douglas , Accola Molly , Rehrauer William , Urh Marjeta 
Published: August 2015

Abstract
Circulating cell-free DNA (ccfDNA) in plasma can be used to detect biomarkers that show great promise for diagnosis and monitoring of cancer, giving rise to the possibility of liquid biopsies that obviate the need for invasive tissue collection. The low concentration and highly fragmented nature of ccfDNA, coupled with the low frequency of potential oncogenic biomarkers, presents challenges and will require a purification method that is efficient and highly reproducible.
Here we describe a method for purifying nucleic acids based on novel surface and binding chemistries. The combination of these two approaches allows for increased binding of fragmented DNA. The method can be partially automated to ensure highly reproducible results. Up to 4mls of plasma can be processed and eluted in as little as 15ul, giving DNA concentrations of 1-10ul. This greatly facilitates use in Next Generation Sequencing.
Using the automated method, ccfDNA was purified from the plasma of 7 patients who had previously undergone surgical resection for malignancy. DNA was also purified from the FFPE malignant tissue off of slides, following macrodissection, from the same patients. NGS was used to interrogate both sample types for potentially oncogenic variants. Several laboratory developed tests, all including COLD-PCR, were also employed to verify the presence or absence of variants. The two types of samples showed excellent correlation on mutations, suggesting that use of a less invasive liquid biopsy has the potential to enable actionable mutation detection without using more invasive solid tumor biopsy means.
Citation Format: Douglas H. White, Douglas Horejsh, Molly Accola, William Rehrauer, Marjeta Urh. Correlation of mutations detected in liquid and tissue biopsies. [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 3383. doi:10.1158/1538-7445.AM2015-3383