bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1064: IL-6 secreted by tumor-associated macrophages promotes DLBCL chemoresistance via expansion of the CSCs population
Authors: Bai Nan
Published: May 2015

Cancer stem-like cells (CSCs), a highly tumorigenic subpopulation of cells found in developmentally diverse tumors, are highly resistant to chemotherapeutic drugs. Tumor-associated macrophages (TAMs) are known to promote progression of tumors and chemoresistance of DLBCL (Diffuse Large B cell Lymphoma). Here, we report that TAMs promote a CSC-like phenotype in DLBCL cells. This was characterized by increased ALDH1A1, Sox-2, Oct-4, Nanog and KLF-4 gene expression. In in vitro studies, we found that co-culture with monocyte cell lines enhanced the chemoresistance and CSC-like phenotypes of DLBCL cells. RNA-seq revealed high levels of IL-6 expression following co-culture with DLBCL, and in fact IL-6 was sufficient to promote the chemoresistance and CSC-like phenotypes of DLBCL cells. Surprisingly, patients exhibited elevated IL-6 after chemotherapy relative to patients pre-chemotherapy, suggesting that chemotherapy may elicit a host response favoring chemoresistance. High levels of serum IL-6 were associated with poor prognosis. In agreement with these results, tumor infiltration by TAMs directly correlated with disease severity. Therefore, IL-6 may be a prognostic marker for outcome in DLBCL.

Citation Format: Nan Bai. IL-6 secreted by tumor-associated macrophages promotes DLBCL chemoresistance via expansion of the CSCs population. [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 1064. doi:10.1158/1538-7445.AM2014-1064
Abstract 1068: Socs3 deficiency in myeloid cells promotes prostate tumor development
Authors: Yu Hao , Qin Hongwei
Published: May 2015

Suppressor Of Cytokine Signaling (SOCS) proteins are negative regulators of the JAK/STAT pathway, and have been implicated as functioning as tumor suppressors, particularly SOCS3. We have previously demonstrated that specific deletion of SOCS3 in myeloid cells leads to heightened activation of STAT3 and downstream STAT3 target gene expression. STAT3 activation has been strongly implicated in contributing to prostate cancer progression and metastasis. STAT3 signaling in myeloid cells has been demonstrated to attenuate anti-tumor immunity. Thus, we evaluated the impact of SOCS3 deletion in myeloid cells in a murine prostate tumor model. We demonstrate that prostate tumor growth is significantly enhanced in myeloid-specific SOCS3-deficient mice, which correlates with elevated levels of Myeloid Derived Suppressor Cells (MDSC) in both the spleen and tumor microenvironment, and less CD8+ T-cell infiltration in tumors. Furthermore, SOCS3-deficient bone-marrow-derived mononuclear cells exhibit heightened STAT3 activation and are preferentially differentiate into MDSC phenotype. Importantly, we identify granulocyte-colony stimulating factor (G-CSF) as a critical factor secreted by the prostate tumor microenvironment that promotes development of Gr-1+CD11b+ cells via a STAT3-depentent pathway. Abrogation of tumor-derived G-CSF reduced the proliferation and accumulation of Gr-1+CD11b+ cells and inhibited prostate tumor growth. Therefore, the tumor-derived cytokine, G-CSF, is a prospective candidate upstream of the STAT3/SOCS3 pathway in MDSC differentiation from the bone marrow. These findings highlight the critical function of SOCS3 as a negative regulator of MDSC development and function, which may contribute to tumor suppressor attributer of SOCS3.

Citation Format: Hao Yu, Hongwei Qin. Socs3 deficiency in myeloid cells promotes prostate tumor development. [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 1068. doi:10.1158/1538-7445.AM2014-1068
Abstract 1072: TAM and CD44 in medullary thyroid carcinoma
Authors: MIYAZAWA MARTA , SANTOS MARIA JOSE C. P. , BIM LARISSA V. , ORTI-RADUAN ERIKA S. L. , VALENTE FLÁVIA O. F. , NUNES ADAUTO F. , DELCELO ROSANA , MACIEL RUI M. B. , CERUTTI JANETE M.
Published: May 2015

Background: Tumor-associated macrophages (TAMs) are alternatively activated or M2 macrophages that infiltrate cancer tissues. It has been suggested that TAMs exert several pro-tumor functions by releasing several growth factors and proangiogenic cytokines that favor tumor progression. In fact, TAM density has been associated with poor prognosis. Although it is well known the pro-tumor roles of TAM in several tumor types, its role in medullary thyroid cancer (MTC) is still unknown. We here evaluated the M2 macrophage marker CD163 in MTC and correlated with RET mutational status and clinical and pathological features. Because it has been suggested TAMs could interact with CD44-positive tumor cells to during tumorigenesis process, we also investigated the expression of CD44 in MTC.

Patients and Methods: CD163 and CD44 expression we investigated in 78 MTC by immunohistochemistry (IHC). Because hereditary form is caused by germline mutations in the RET gene, all patients were screened for RET mutations (exons 8, 10, 11, 13-16) in the DNA isolated from blood samples. Those MTC that were negative for RET germline mutations, were also screened for somatic mutations in the RET gene (exons 10, 11 e 16).

Results: Germline mutation in the RET gene were identified in 29 patients (p.G533C, p.C609Y, p.C611Y, p.C620Y, p.C634R, p.C634Y/Y791F, p.S891A and p.M918V). Approximately 49 cases are sporadic cases in which somatic RET mutations were identified in about 6 cases (p.M918T, p.C634R and p.C634Y). CD163 expression was mainly found in sporadic MTC when compared to hereditary MTC (p=0.021), suggesting that TAM may play a role in the progression of sporadic MTC. On the other hand CD44 expression was mainly found in hereditary MTC than in sporadic cases (p=0.017), particularly in patients with RET germlime mutation at codon C634.

Conclusion: TAM seems to be more important for sporadic MTC tumorigenesis when compared to hereditary MTC. On the other hand, CD44 expression correlated with hereditary MTC, particularly in patients with mutation at codon C634.

Citation Format: MARTA MIYAZAWA, MARIA JOSE C. P. SANTOS, LARISSA V. BIM, ERIKA S. L. ORTI-RADUAN, FLÁVIA O. F. VALENTE, ADAUTO F. NUNES, ROSANA DELCELO, RUI M. B. MACIEL, JANETE M. CERUTTI. TAM and CD44 in medullary thyroid 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 1072. doi:10.1158/1538-7445.AM2014-1072
Abstract 1076: Antagonists of the chemokine receptor CCR4 reverse the tumor-promoting microenvironment of renal cancer
Authors: Berlato Chiara , Kahn Moddasar N. , Schioppa Tiziana , Thompson Richard , Maniati Eleni , Canosa Monica , Kulbe Hagen , Sheldon Chris , Wreggett Keith , Hagemann Urs , Duncan Alexander , Fletcher Laura , Wilkinson Robert W. , Powles Thomas , Quezada Sergio , Balkwill Frances
Published: May 2015

Tumor microenvironments posses complex chemokine networks that contribute to the extent and phenotype of the host infiltrate. Malignant cells may gain functional chemokine receptors, often as a consequence of oncogenic mutations, allowing them to respond to distant chemokine gradients during metastasis. The chemokine receptor CCR4 was highly expressed in human renal cell carcinoma, RCC, biopsies and RCC patient plasma had abnormal levels of CCR4 ligands. However, during pre-clinical evaluation of CCR4 as a target in RCC, we found that both a small molecule CCR4 inhibitor and an anti-CCR4 antagonistic antibody had unexpected and novel anti-tumor activity in the mouse RCC RENCA model. CCR4 antagonists did not reduce the proportion of infiltrating leukocytes in the tumor microenvironment but altered the phenotype of myeloid cells, increased NK cells and Th1 cytokine levels, as well as reducing splenic MDSC infiltrate, and blood chemokine levels. Although the most prominent changes were in the myeloid compartment, anti-tumor activity was lost in athymic mice, supporting a role for the adaptive immune system in CCR4 antagonist action. CCR4 antagonists, alone, or in combination with other immune modulators, may be of interest in human cancers with high levels of tumor CCR4 and abnormal plasma CCR4 ligand levels.

Citation Format: Chiara Berlato, Moddasar N. Kahn, Tiziana Schioppa, Richard Thompson, Eleni Maniati, Monica Canosa, Hagen Kulbe, Chris Sheldon, Keith Wreggett, Urs Hagemann, Alexander Duncan, Laura Fletcher, Robert W. Wilkinson, Thomas Powles, Sergio Quezada, Frances Balkwill. Antagonists of the chemokine receptor CCR4 reverse the tumor-promoting microenvironment of renal 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 1076. doi:10.1158/1538-7445.AM2014-1076
Abstract 108: Consequences of hepatic JAK2 deficiency for liver metabolism and hepatocarcinogenesis
Authors: Themanns Madeleine , Friedbichler Katrin , Kessler Sonja M. , Schlederer Michaela , Kenner Lukas , Wagner Kay-Uwe , Haybaeck Johannes , Moriggl Richard
Published: May 2015

The metabolic syndrome is a frequent disease in the western world due to increased prevalence of obesity and diabetes mellitus. Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of the metabolic syndrome associated with primary stages of hepatocellular carcinoma (HCC). Hepatic JAK2-STAT5 signaling is mainly activated by growth hormone (GH) which controls cellular metabolism.

To address the role of hepatic JAK2 in lipid homeostasis and hepatocarcinogenesis, we crossed a mouse model of inflammatory liver cancer caused by hyperactivated GH signaling (GHtg) to mice harboring the hepatocyte-specific deletion of JAK2 (J2KO; using AlfpCre). While excess of GH caused chronic hepatitis, as well as pathologic alterations such as big hepatocytes with large polymorphic nuclei, severe and progressive hepatosteatosis was evident in GHtg:J2KO and J2KO mice as soon as 12 weeks of age. Hepatosteatosis in JAK2 deficient mice, independent of GH overexpression, was due to increased hepatic lipid synthesis and peripheral lipolysis associated with elevated unsaturated fatty acid (FA) and triglyceride (TG) amounts in the liver. However, microvesicular steatosis, which is associated with a more severe pathology, was more abundant in GHtg:J2KO livers accompanied by significantly elevated liver/body weight ratios. Surprisingly, loss of hepatic JAK2 proteins led to delayed hepatocarcinogenesis in aged mice. Currently, we are investigating the involvement of NAFLD in the pathogenesis of HCC development by genetic and histo-pathologic profiling. We will provide molecular and cellular insights responsible for delayed hepatocarcinogenesis in GHtg:J2KO and J2KO mice.

Citation Format: Madeleine Themanns, Katrin Friedbichler, Sonja M. Kessler, Michaela Schlederer, Lukas Kenner, Kay-Uwe Wagner, Johannes Haybaeck, Richard Moriggl. Consequences of hepatic JAK2 deficiency for liver metabolism and hepatocarcinogenesis. [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 108. doi:10.1158/1538-7445.AM2014-108
Abstract 1082: IL27 promotes papilloma formation via inducing a pro-inflammatory milieu in the skin
Authors: Dibra Denada , Xia Xueqing , Newman Melissa , Keenan Camille , Li Shulin
Published: May 2015

Ras activation plays an important role in Squamous Cell Carcinomas (SCC) development. Additionally, there is large evidence confirming the role of inflammation during cancer initiation. However, the interaction between inflammation and oncogene activation is poorly understood in tumorigenesis. We found that IL27 promotes papilloma formation in a 2 step skin carcinogenesis (DMBA followed by benzoyl peroxide) model where DMBA causes Ras mutation. Because K15-positive follicular stem cells contribute to papillomas in the two-step skin carcinogenesis model, we used an inducible oncogenic K-RasG12D under the K15 promoter, which marks follicular stem cells. Indeed, treating mice with IL27 increased papilloma incidence earlier in these K15-K-RASG12D mice. Mechanistically, we see that ETAR+ macrophages are significantly increased in IL27-treated K15-K-RasG12D mice. Additionally, the ETAR ligand ET1, and the downstream factor of ETAR, COX2, are upregulated in these K15-KRasG12D mice by IL27, suggesting that ET1/ETAR pathway is involved in IL27 mediated papilloma formation. Indeed, IL27-mediated papilloma formation was reversed by using the ETAR inhibitor ZD4054. Therefore, the data shown here suggest that IL27 drives accumulation of ETAR+ macrophages, ET1, and Cox-2 in the skin and ultimately causes faster papilloma formation in K-Ras mutated follicular stem cells. These findings propose an unrecognized role of IL27 during initiation of skin carcinogenesis.

Citation Format: Denada Dibra, Xueqing Xia, Melissa Newman, Camille Keenan, Shulin Li. IL27 promotes papilloma formation via inducing a pro-inflammatory milieu in the skin. [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 1082. doi:10.1158/1538-7445.AM2014-1082
Abstract 1083: Host-tumor immune response for early breast cancer patients treated with radiofrequency ablation therapy
Authors: Imoto Shigeru , Nakatsugawa Noriko , Ueno Takayuki , Ito Hiroki , Imi Kentaro , Miyamoto Kaisuke , Kitamura Manami , Isaka Hirotsugu , Nakatsura Tetsuya
Published: May 2015

[Background] We demonstrated immune suppression of regulatory T (Treg) cells in preoperative breast cancer (BC) patients at AACR 2011. Last year we also reported at this meeting that Th17 cells might have some potential to control tumor progression in the same cohort. Modern treatment of operable BC consists of breast surgery, drug therapy and radiation therapy. [Aim] To explore new strategy of BC treatment, we conducted a phase II study on radiofrequency ablation (RFA) in early BC between 2009 and 2013. Twenty patients were enrolled. To examine host-tumor immune response under thermal ablation therapy, Treg cells in peripheral blood mononuclear cells (PBMC) and plasma IL-17A were measured. [Patients and methods] Blood samples were collected from 13 patients before RFA and at the time of 1 month after RFA. Treg cells were examined by counting CD4+CD25highCD127low/-cells in PBMC. Plasma IL-17A was measured using cytometric beads array system. Statistical significance was analyzed using Mann-Whitney U-test. [Results] As of November 2013, all patients were free of recurrence. The percentages of Treg cells had no significant change in 13 patients before and after RFA (2.8% versus 2.7% of CD4-positive cells at mean value). In addition, there was no statistical difference in levels of plasma IL-17A before and after RFA (76 pg/ml versus 116 pg/ml at mean level). [Discussion] Unexpectedly, RFA had no favorable immune response in BC patients, because we observed significant decrease in percentages of Treg cells after breast surgery. The reason is that most patients had T1 tumor and Luminal A-like BC. They had lower percentages of Treg cells in comparison to those of tumor-bearing patients reported previously (2.8% versus 4.2%). [Conclusion] RFA is a promising alternative to breast surgery. However, it may make little effect on host-tumor immune response in favorable subtype of early BC.

Citation Format: Shigeru Imoto, Noriko Nakatsugawa, Takayuki Ueno, Hiroki Ito, Kentaro Imi, Kaisuke Miyamoto, Manami Kitamura, Hirotsugu Isaka, Tetsuya Nakatsura. Host-tumor immune response for early breast cancer patients treated with radiofrequency ablation 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 1083. doi:10.1158/1538-7445.AM2014-1083
Abstract 1085: Glioma-infiltrating myeloid derived suppressor cells inhibit anti-tumor T cell responses
Authors: Kamran Neha , Assi Hikmat , Candolfi Marianela , Moreno Mariela , Li Youping , Lowenstein Pedro R. , Castro Maria G.
Published: May 2015

Efficacy of immunotherapeutic approaches against glioma is limited by the immunosuppressive tumor microenvironment. Tumor derived TGF-β, IL-10 and Prostaglandin E2 along with the presence of regulatory T cells (Tregs) and tumor associated macrophages (TAMs) promote the immune escape in gliomas. Also, tumor derived factors induce the expansion of myeloid derived suppressor cells (MDSCs). MDSCs represent a heterogeneous population of myeloid cells at various stages of differentiation that have the potential to inhibit anti-tumor T cell responses. Herein we demonstrate the accumulation of MDSCs in GL26 brain tumor bearing mice. Absolute numbers of Ly-6G+ (Gr-1high) MDSCs showed a 200 fold increase within the tumor mass 28 days post-tumor implantation. In contrast, the numbers of Ly-6C+ (Gr-1low) MDSCs did not significantly change within the tumor microenvironment. While this massive influx of MDSCs was noted within intracranial tumors, the levels of Ly-6G+ or Ly-6C+ MDSCs did not increase in the tumor draining lymph nodes (dLNs), spleen, bone marrow or blood of intracranial tumor bearing mice. Mice bearing GL26 or B16-F0 tumors in the flank showed a ∼3 fold increased influx of Ly-6G+ MDSCs within the tumor mass, the spleen and circulating MDSCs. Ly-6G+ MDSCs isolated from the brain tumors and spleens of GL26 intracranial tumor bearing mice inhibited tumor antigen-specific CD8+ T cell proliferation and T cell proliferation mediated by CD3 ligation . On the other hand, Ly-6C+ MDSCs did not did not elicit inhibition of T cell proliferation. Preliminary experiments using tumor cells' conditioned media indicate that CXCR2 signaling mediates the migration of MDSCs in a transwell assay and suggest the possibility that it could mediate MDSCs' migration into the tumor microenvironment in vivo. Overall, our data shows that MDSCs accumulate within the glioma mass and inhibit tumor-specific T cell responses. Strategies that inhibit MDSC recruitment to the tumor microenvironment and/or block their activity may therefore enhance the T cell mediated tumor clearance and suppress glioma progression.

Supported by National Institutes of Health/ National Institute of Neurological Disorders & Stroke (NIH/NINDS) Grants RO1-NS074387 and RO1-NS054193

Citation Format: Neha Kamran, Hikmat Assi, Marianela Candolfi, Mariela Moreno, Youping Li, Pedro R. Lowenstein, Maria G. Castro. Glioma-infiltrating myeloid derived suppressor cells inhibit anti-tumor T cell responses. [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 1085. doi:10.1158/1538-7445.AM2014-1085
Abstract 1089: Matrix stiffening and β1 integrin promote fibroblast accumulation in lung squamous cell carcinomas but not in adenocarcinomas
Authors: Alcaraz Jordi , Puig Marta , Lugo Roberto , Giménez Alícia , Velásquez Adriana , Galgoczy Roland , Ramírez Josep , Gómez-Caro Abel , Gascón Pere , Reguart Noemi
Published: May 2015

The mechanisms underlying the abundance of tumor associated fibrobasts (TAFs) in non-small cell lung cancer (NSCLC) remain poorly understood. To address this gap of knowedge, we examined the relative contribution of mechanical (i.e. matrix rigidity) and soluble biochemical (i.e. serum) cues in the accumulation of primary TAFs from either adenocarcinoma (ADC) or squamous cell carcinoma (SQC) NSCLC patients. For this purpose, fibroblasts were cultured on collagen-I coated gels engineered to exhibit either normal- or tumor-like stiffnesses at different serum concentrations. In fibroblasts from non-malignant tissue, matrix stiffening alone was sufficient to increase fibroblast accumulation by 20%. In addition, matrix stiffening-induced accumulation was dominant or comparable to that due to soluble growth factors up to moderate serum concentrations. These mechanical stimulatory effects were β1 integrin-dependent, and were associated with both increased integrin mechanosensing through FAKpY397and a post-transcriptionally-driven rise in β1 integrin expression. The latter mechanoregulatory circuit could be extended to TAFs in a subtype-dependent fashion, since SQC-TAFs exhibited higher FAKpY397 and β1 expression than ADC-TAFs. Remarkably, SQC-TAF density was enhanced > 50% in response to matrix stiffening, whereas they were largely desensitized to serum. Conversely, substantial accumulation of ADC-TAFs required large serum concentration, whereas it was poorly induced by either matrix stiffening or low serum concentration. These results reveal that a therapeutic strategy aiming to inhibit soluble growth factors may be effective against ADC-TAFs, whereas a strategy aiming to rescue normal lung elasticity may be more efficient against SQC-TAFs.

Citation Format: Jordi Alcaraz, Marta Puig, Roberto Lugo, Alícia Giménez, Adriana Velásquez, Roland Galgoczy, Josep Ramírez, Abel Gómez-Caro, Pere Gascón, Noemi Reguart. Matrix stiffening and β1 integrin promote fibroblast accumulation in lung squamous cell carcinomas but not in adenocarcinomas. [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 1089. doi:10.1158/1538-7445.AM2014-1089
Abstract 109: PET imaging of 89Zr-labeled Pertuzumab in HER2-positive breast cancer xenografts
Authors: Marquez Bernadette V. , Ikotun Oluwatayo F. , Wright Brian , Zheleznyak Alexander , Richard Pierce , Lapi Suzanne E.
Published: May 2015

The sensitivity and quantitative properties of Positron Emission Tomography (PET) imaging combined with the selectivity and high affinity of radiolabeled monoclonal antibodies (mAbs) make a powerful tool in molecular imaging of diseases including breast cancer. Radiolabeling mAbs with the positron-emitting 89Zr has recently been useful in clinical trials due to its relatively long half-life (t1/2 = 3.3 days), which matches the pharmacokinetic properties of mAbs. Pertuzumab (Perjeta™) is an FDA-approved mAb for the treatment of human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer, in combination with Trastuzumab (Herceptin™) and chemotherapy. Herein, we evaluated 89Zr-labeled Pertuzumab as a PET imaging agent in transgenic mice-bearing human breast cancer. The 89Zr chelator, p-isothiocyanatobenzyl-desferrioxamine, was conjugated to Pertuzumab and subsequently radiolabeled with 89Zr. The immunoreactivity and specificity of 89Zr-Pertuzumab for HER2-expressing cells were determined in vitro and showed retention of 89Zr-Pertuzumab immunoreactivity and specific binding to HER2-expressing cells. Human breast cancer cells were inoculated subcutaneously in severely immunocompromised NOG mice, a model which allows for the growth of HER2-positive tumors without exogenous stimuli. 89Zr-Pertuzumab was injected via tail vein and imaged and 5 and 7 days post-injection (p.i.) followed by biodistribution studies. Optimal contrast was achieved at 5 days p.i., with higher tumor uptake in the HER2-positive xenograft than the HER2-negative model. Immunohistochemical analysis of these tumors is in agreement with PET imaging analysis. These results illustrate that 89Zr-Pertuzumab may be beneficial for the noninvasive assessment of HER2 expression.

Citation Format: Bernadette V. Marquez, Oluwatayo F. Ikotun, Brian Wright, Alexander Zheleznyak, Pierce Richard, Suzanne E. Lapi. PET imaging of 89Zr-labeled Pertuzumab in HER2-positive breast cancer xenografts. [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 109. doi:10.1158/1538-7445.AM2014-109
Abstract 1094: Dynamics of Gemcitabine induced interleukin-8 (IL-8) expression in pancreatic tumor microenvironment
Authors: Gomez Sobeyda , Fujii Takahiko , Huang Haojie , Hwang Rosa , Ramachandran Viji , Logsdon Craig , Arumugam Thiru
Published: May 2015

Background: The clinical standard of care for patients with pancreatic ductal adenocarcinoma (PDAC) is treatment with Gemcitabine (Gem) despite Gem's limited benefits. To date, no surrogate marker has been identified to indicate whether Gem treatment directly affects PDAC tumor cells. In order to identify such a marker, we analyzed Gem treated cell lines and clinical samples. Methods: 12 PDAC cell lines were treated with 5μM Gem for three hours and then allowed to grow in the absence of Gem for 24hrs before mRNA expression analysis (Illumina Gene Expression Array). IHC and WB were used to quantify IL-8 expression. ShRNA mediated silencing was utilized to study the therapeutic value of IL-8. Results: mRNA expression and WB confirmed the induction of IL-8 after Gem treatment. Gem induced IL-8 expression was transcriptionally controlled by NFκB and C/EBP. PDAC cells (MPanc96 and BxPc-3-CXCR1), HPSC (Human Pancreatic Stellate Cells-CXCR1) and HUVEC (Human Umbilical Vein Endothelial cells-CXCR1 & 2) expressed the receptor of IL-8. Conditioned media from Gem treated cells and rIL-8 treated cells, stimulated cell growth (PDAC, HPSC and HUVEC), polygon formation in HUVEC and α-SMA expression in HPSC. Stable silencing of IL-8 in Capan2 cells, which develop an abundant stroma, led to a significant reduction in tumor volume. Histologically, IL-8 silenced tumors showed reduced micro-vessel density (CD37), as well as highly reduced desmoplasia (Trichrome stain & α-SMA) associated with necrosis. Further, IHC revealed strong IL-8 expression in neo-adjuvant Gem-treated human PDAC tissues (strong expression 42.1%, weak expression 57.9%, negative 0%) in comparison to tissue from patients that underwent surgery alone (strong expression 0%, weak expression 77.8%, negative 22.2%).Conclusion: Gem induced IL-8 functions as a growth factor for cancer cells and its microenvironment. Thus, IL-8 can serve as a surrogate marker to indicate Gem effects in PDAC.

Citation Format: Sobeyda Gomez, Takahiko Fujii, Haojie Huang, Rosa Hwang, Viji Ramachandran, Craig Logsdon, Thiru Arumugam. Dynamics of Gemcitabine induced interleukin-8 (IL-8) expression in pancreatic tumor microenvironment. [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 1094. doi:10.1158/1538-7445.AM2014-1094
Abstract 1095: microRNA-26a expression may suppress tumor growth by modulating macrophage infiltration in tumor through down-regulation of M-CSF in hepatocellular carcinoma
Authors: Chai Zong-Tao , Zhu Xiao-Dong , Ao Jian-Yang , Kong Ling-Qun , Zhang Yuan-Yuan , Sun Hui-Chuan
Published: May 2015

Purpose

To Study molecular changes specific to tumor-derived endothelial cells.

Materials and methods

Tumor tissue and adjacent nontumor tissue were obtained from 27 hepatocellular carcinoma (HCC) patients. Primary cultured CD31+ and CD105+ tumor endothelial cells (TECs) and nontumor endothelial cells (NECs) were isolated by magnetic-activated cell sorting. Affymetrix GeneChip Human Gene ST Arrays were used to determine gene expression profiles of HCC cells and matched TECs and NECs. A capillary tube formation assay was used to evaluate tube formation by the endothelial cells. The tumorigenicity of isolated TECs was monitored in nonobese diabetic/severe combined immunodeficient mice.

Results

The isolated CD31+ and CD105+ TECs and NECs displayed features of endothelial cells. Both cultured HCC cells and TECs induced capillary tube formation in vitro and were incorporated into tumor vasculature in vivo. The TEC isolates had a gene signature resembling that of HCC cells, and TEC-specific genes were associated with poorer HCC survival.

Conclusions

A subset of TECs may originate from tumor cells, and they express a unique set of genes linked to HCC prognosis.

Note: This abstract was not presented at the meeting.

Citation Format: Zong-Tao Chai, Xiao-Dong Zhu, Jian-Yang Ao, Ling-Qun Kong, Yuan-Yuan Zhang, Hui-Chuan Sun. microRNA-26a expression may suppress tumor growth by modulating macrophage infiltration in tumor through down-regulation of M-CSF in hepatocellular 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 1095. doi:10.1158/1538-7445.AM2014-1095
Abstract 1097: Potentiating antitumor CD4+ T cell responses with chemotherapeutic agents
Authors: Zhou Gang , Lu Xiaoyun
Published: May 2015

Chemotherapy is a major treatment modality for many types of cancers. Even though chemotherapeutic drugs are chosen for their cytotoxicity toward cancerous cells, increasing numbers of anticancer drugs have been found to exert immune enhancing effects through a variety of mechanisms. These findings have led to a growing recognition that elicitation of endogenous host immunity may intrinsically contribute to the efficacy of some antineoplastic agents. Although standard chemotherapy can reduce the symptoms of cancer, chemotherapy alone is rarely curative. Tumor relapses often occur in patients after the initial treatment, suggesting that the endogenous antitumor immunity elicited by chemotherapy is not sufficient or durable enough to support long-term therapeutic efficacy. There is accumulating evidence that integration of chemotherapy and immunological maneuvers, such as adoptive T-cell therapy (ACT) and therapeutic vaccines, can effectively treat established tumors. In a mouse model of B-cell lymphoma, we previously reported that polyfunctional CD4+ effector cells arising from ACT play a critical role in sustaining an effective antitumor immunity in the post-chemotherapy setting. In the current study, we have screened a panel of widely used chemotherapeutic agents and identified those that can exert immunostimulatory effects on tumor-specific CD4+ T cells. We also examined the impact of these drugs on lymphoid and myeloid cell homeostasis, and cytokine/chemokine milieu. These data provide insight into the mechanisms by which certain anticancer drugs potentiate antitumor CD4+ T cell responses.

Citation Format: Gang Zhou, Xiaoyun Lu. Potentiating antitumor CD4+ T cell responses with chemotherapeutic agents. [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 1097. doi:10.1158/1538-7445.AM2014-1097
Abstract 1107: Tumor microenvironment based modulation of thyroid cancer phenotype
Authors: Tuli Neha Y. , Cabin Jonathan , Suriano Robert , Bednarczyk Robert , Hanly Elyse , Geliebter Jan , Shin Edward , Tiwari Raj K.
Published: May 2015

Inflammation plays a pivotal role in the progression of solid malignant tumor with studies showing that the presence of specific inflammatory-immune cells, such as macrophages, at the tumor site leads to poor prognosis. M1 polarized macrophages secrete pro-inflammatory chemokines and cytokines which induce an epithelial to mesenchymal transition (EMT) in tumor cells; a process where epithelial cells acquire mesenchymal traits, thus facilitating tissue infiltration and consequent metastasis. EMT as a marker of cancer progression is understudied in thyroid cancer. In our present study, we evaluated the crosstalk between the macrophages and the epithelial cells in the thyroid tumor microenvironment with the use of an in vitro model system consisting of an immortalized thyroid cell line (Nthy-ori 3-1), three papillary cancer cell lines (BCPAP, 8505C and TPC-1) and one follicular cancer cell line (CGTHW-1). We observed the halt in proliferation of the thyroid cancer cells as the epithelial cells differentiate into mesenchymal cells under the influence of activated macrophage conditioned media. We also observed a statistically significant (p<0.05) upregulation of migration and invasion of thyroid tumor cells in presence of macrophage conditioned media. Using nuclear and cytoplasmic extracts from the thyroid cancer cell lines, we observed that EMT markers including E-cadherin, β-catenin, vimentin, NFk-B, snail, slug and twist are modulated in response to activated macrophage conditioned media. Downregulation of E-cadherin, required for maintenance of stable junction and β-catenin essential for cell-cell adhesion was noticed in response to macrophage conditioned media. Transcription factors like NFk-B, snail and slug were translocated to the nucleus, which is indicative of the initiation of EMT. Our data provides evidence that macrophage secreted proteins play a crucial role in epithelial-mesenchymal transition in thyroid tumor advancement and metastasis. We have successfully identified some significant markers including transcription factors such as NFk-B, slug, twist and snail that play a critical role in the induction of epithelial to mesenchymal transition in thyroid cancer. These findings will allow for the possible development of targeted therapy designed at inhibiting EMT and subsequent suppression of thyroid cancer metastasis and dissemination.

Citation Format: Neha Y. Tuli, Jonathan Cabin, Robert Suriano, Robert Bednarczyk, Elyse Hanly, Jan Geliebter, Edward Shin, Raj K. Tiwari. Tumor microenvironment based modulation of thyroid cancer phenotype. [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 1107. doi:10.1158/1538-7445.AM2014-1107
Abstract 1109: The antimicrobial peptide LL37 activates plasmacytoid dendritic cells in breast cancer
Authors: Vey Nelly , Blanc Elena , Sisirak Vanja , Thys Sandra , Beux Céline Le , Goutagny Nadège , Treilleux Isabelle , Marabelle Aurélien , Blay Jean-Yves , Caux Christophe , Bendriss-Vermare Nathalie
Published: May 2015

Plasmacytoid dendritic cells (pDC) are the main producers of type I IFNs in response to viral and self nucleic acids that trigger endosomal TLR7 and 9. They have been recently described in various solid tumors. In breast tumors, we demonstrated that tumor-associated (TA)pDC exhibit a partially mature phenotype, suggesting that endogenous activating signals are present in tumor microenvironment (TME). Importantly, type I IFN was shown to play a major role in tumor immunosurveillance and we observed a type I IFN signature in human breast tumors. Altogether these observations lead us to investigate whether, in the initiating phase of tumorigenesis, TApDC might be activated by endogenous TLR ligands released in the TME that may trigger their IFN-a production, as observed in auto-immune disorders in response to [self nucleic acids-antimicrobial peptide LL37] complexes. First, we demonstrated that hCAP18/LL37 is expressed by a subset of CD45+ cells within the breast TME. Importantly, [self nucleic acids-LL37] complexes purified from breast TME were able to trigger IFN-a production in healthy pDC in vitro demonstrating their functionality. Finally, using syngenic murine mammary tumor models preliminary data showed that tumor cell growth is accelerated in IFNARko mice and pDC-depleted mice compared to wild-type mice suggesting a role for type I IFN and pDC in controlling early tumor development. Thus, our work aimed at demonstrating that restoring pDCs' immunosurveillance function might represent an attractive therapeutic strategy for localized breast tumors.

Support : Ligue contre le cancer, Fondation ARC (SFI20111203835) and INCA (2011-1-PL BIO-12-IC-1).

Citation Format: Nelly Vey, Elena Blanc, Vanja Sisirak, Sandra Thys, Céline Le Beux, Nadège Goutagny, Isabelle Treilleux, Aurélien Marabelle, Jean-Yves Blay, Christophe Caux, Nathalie Bendriss-Vermare. The antimicrobial peptide LL37 activates plasmacytoid dendritic cells in breast 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 1109. doi:10.1158/1538-7445.AM2014-1109
Abstract 1111: Hypoxia inducible factor regulation of galectin3 expression in neuroblastoma cells:Implications in controlling malignant phenotype of neuroblastoma cells
Authors: Wesley Umadevi V. , Resad Esat , Dempsey Robert J.
Published: May 2015

Neuroblastoma (NB) is an extra cranial tumor arising from neural crest progenitor cells. Effective angiogenesis, or new blood vessel formation, is critical for NB tumor growth and progression. Elevated levels of galectin-3 (Gal-3), an angiogenic cytokine is extensively correlated with the malignant behavior and poor prognosis of many cancers. Our studies have shown that Gal-3 expression is significantly up-regulated in aggressive NB cells, and Gal-3 promotes angiogenesis and migration of microglial cells. We have also previously reported that Gal-3 expression is up regulated under low oxygen/hypoxic conditions. The specific mechanisms of Gal-3 induction in NB are not understood. Hypoxic microenvironment drives malignant phenotypes of cancer cells through the transcription factor hypoxia-inducible factor (HIF1). Because NB cells reside in a low oxygen environment, we determined if the hypoxic status modulates Gal-3 expression. In this study, we utilized RT-PCR, western blot analysis, immunofluorescence staining, RNA interference and biochemical approaches. The hypoxia-mimetic, cobalt chloride (CoCl2)-treated neuroblastoma Neuro-2a cells showed enhanced levels of HIF 1 protein. In correlation with the increased HIF1 levels, Gal-3 expression was increased at both RNA and protein levels. Silencing of HIF1 expression by small hairpin interfering RNA in Neuro-2a cells blocked hypoxia induced Gal-3 expression indicating that HIF1 regulates Gal-3 expression in NB cells. Down regulation of Gal-3 resulted in decreased levels of the angiogenic factors IL-6 and urokinase plasminogen activator in association with decreased proliferation, migration, and angiogenesis. Thus our data suggest that HIF1alpha plays a role in the regulation of Gal-3 expression and malignant phenotype of NB cells.

Note: This abstract was not presented at the meeting.

Citation Format: Umadevi V. Wesley, Esat Resad, Robert J. Dempsey. Hypoxia inducible factor regulation of galectin3 expression in neuroblastoma cells:Implications in controlling malignant phenotype of neuroblastoma 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 1111. doi:10.1158/1538-7445.AM2014-1111
Abstract 1119: Utilization of the TGFβ signaling pathway and cell substrate interaction in a novel anti-cancer drug screen
Authors: Kim Wontak , Hoj Jacob P. , Saguibo Nicholas E. , Fullmer Kendra E.
Published: May 2015

The TGF-β signaling pathway has been demonstrated to play a multifunctional and complicated role in cancer progression, making it an intriguing target for anti-cancer therapeutics. TGF-β signaling drives proliferation of cancer cells, invasion at the tumor periphery, and is associated with metastatic potential in a number of cancer types. Tumors expressing TGF-β activity are positively correlated with poorer prognosis in patients. Complicating the role of TGF-β signaling in cancer progression is that TGF-β signaling leads to distinct cellular responses at different stages of cancer progression. How the same signal transduction pathway drives distinct cellular responses is a critical question. One likely possibility is that TGF-β signaling is highly context dependent. Changes in the tumor microenvironment, as occur during cancer progression, alter the outcome of TGF-β signaling. As an extreme example of how TGF-β signaling is affected by micro-environmental stimuli, we and others previously reported that certain non-cancerous cells on rigid collagen I substrates become sensitized to HGF-induced epithelial scattering in response to TGF-β, while cells on pliant collagen I substrates undergo apoptosis in response to TGF-β. Given that tumors are typically rigid tissues, we sought to define whether cancer cells would respond to TGF-β by undergoing apoptosis when cultured on pliant substrates. We plated a wide variety of cancer cell lines on highly pliant substrates, treated then with TGF-β, and observed cell viability over time. While a number of cells showed no apoptotic response to TGF-β signaling under any condition, we find that a significant number of cancer cells derived from solid tumors respond to TGF-β signaling on pliant substrates by undergoing apoptosis. Another group of cell lines undergo apoptosis on pliant substrates in the absence of any TGF-β stimulation. Reasoning that perturbation of cellular signaling that communicated substrate rigidity to cells might sensitize them to apoptosis in response to TGF-β, we designed a high-content high throughput screen to look for molecules that would induce cells to undergo apoptosis in response to TGF-β signaling. This chemical genetics approach will yield cues into the mechanism of tumor microenvironment sensing, as well as provide lead compounds for development of novel therapeutics

Note: This abstract was not presented at the meeting.

Citation Format: Wontak Kim, Jacob P. Hoj, Nicholas E. Saguibo, Kendra E. Fullmer. Utilization of the TGFβ signaling pathway and cell substrate interaction in a novel anti-cancer drug screen. [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 1119. doi:10.1158/1538-7445.AM2014-1119
Abstract 1128: Thrombomodulin mediates the migration of cervical cancer cells through the regulation of epithelial-mesenchymal transition biomarkers
Authors: Chang Yu-Jia , Wei Po-Li , Huang Ming-Te
Published: May 2015

Thrombomodulin (TM) has been shown to regulate many physiological and pathological processes, including inflammation, thrombosis, and tumor progression. TM is also a natural anticoagulant that maintains circulatory homeostasis in endothelial cells. However, little is known regarding the role of TM in the progression and metastasis of cervical cancer.

TM-specific RNA interference and a cDNA expression vector were used to manipulate TM expression in cervical cancer cells. Cell growth and cell migration were evaluated using the MTT assay, transwell migration assays, and a biosensor system.

TM silencing did not affect the growth rate of the cells. However, cell migration was dramatically enhanced after silencing of TM in HeLa cells. The overexpression of TM in cervical cancer cells only slightly influenced their proliferative capacity. After overexpression of TM in HeLa cells, their migratory capability was suppressed. Furthermore, we found that the decreased expression of E-cadherin and increase of zeb-1 and snail expression in TM-silenced cells which may be correlated with the results of knocking-down TM increases the migratory ability in this study.

In concludion, our results demonstrate that TM may slightly regulate the growth but played the important role in the migratory ability of cervical cancer cells, suggesting that TM could potentially serve as a novel prognostic and therapeutic target in cervical cancer.

Citation Format: Yu-Jia Chang, Po-Li Wei, Ming-Te Huang. Thrombomodulin mediates the migration of cervical cancer cells through the regulation of epithelial-mesenchymal transition biomarkers. [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 1128. doi:10.1158/1538-7445.AM2014-1128
Abstract 1134: Slug promotes survival during metastasis through suppression of Puma-mediated apoptosis
Authors: Hazan Rachel
Published: May 2015

Tumor cells must overcome apoptosis to survive throughout metastatic dissemination and distal organ colonization. Here we show in the Polyoma Middle T mammary tumor model that N-cadherin causes Slug upregulation, which promotes carcinoma cell survival. Slug was dramatically upregulated in distant metastases relative to primary tumors. Consistent with a role in metastasis, Slug knockdown in metastatic carcinoma cells suppressed pulmonary colonization, due to reducing cell survival, but had no effect on tumor cell invasion or extravasation. In support of a role in cell survival, Slug inhibition by shRNA, sensitized tumor cells to apoptosis by genotoxic stress, resulting in caspase-3 activation and PARP cleavage. Furthermore, the effects of Slug on cell survival were due to direct repression of the pro-apoptotic gene, Puma. Importantly, the survival function of the SLUG-PUMA axis was confirmed in human breast cancer cells, where Slug knockdown increased Puma expression and inhibited lung colonization. Thus, our study demonstrates a pivotal role for Slug in cell survival, which is beyond its role in epithelial-to-mesenchymal transition, implying that disruption of the SLUG-PUMA axis may impinge on the survival of metastatic cancer cells.

Citation Format: Rachel Hazan. Slug promotes survival during metastasis through suppression of Puma-mediated apoptosis. [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 1134. doi:10.1158/1538-7445.AM2014-1134