bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5064: CORO1B amplification and expression status identifies an aggressive subset of chromosome 11q13 amplified HNSCC
Authors: Allen Jessica L. , Walk Elyse L. , Rhodes Kristen L. , Beatty Colleen J. , Markwell Steven M. , Papenberg Brenen W. , Interval Erik T. , Wu Hong , Varella Garcia Marileila , Bear James E. , Weed Scott A.
Published: July 2016

Head and neck squamous cell carcinoma (HNSCC) is highly invasive cancer type that occurs with greater incidence in West Virginia and the rest of Appalachia. The chromosome 11q13 region is amplified in approximately 30% of late stage HNSCC cases and is associated with a poor patient prognosis. The core 11q13 region encodes the well-studied tumor genes CCND1 (cyclin D1) and CTTN (cortactin). The CORO1B (coronin 1B) gene flanks the 11q13 core and is amplified in 9-14% of all HNSCC, but how CORO1B amplification contributes to HNSCC is unknown. Coronin 1B governs cell motility by negatively regulating F-actin stability through displacement of cortactin at actin related protein 2/3 (Arp 2/3) branch points, generating dynamic turnover of Arp2/3-F-actin networks required for productive cell movement. Kaplan-Meier analysis of two independent patient cohorts indicates that HNSCC cases with CORO1B amplification have significantly reduced overall survival. Cox hazard ratios also indicate the CORO1B amplification is strongly associated with increased mortality in both cohorts. Automated quantitative analysis (AQUA) of coronin 1B expression in HNSCC tissue microarrays indicates that coronin 1B overexpression decreases median survival of HNSCC patients from 81 to 29 months. Reduced expression of coronin 1B by RNAi-mediated knockdown in established HNSCC cell lines decreases several actin-mediated invasive processes, including invadopodia formation and extracelluar matrix degradation. Collectively these results suggest that elevated coronin 1B expression levels in HNSCC function to enhance tumor invasion, potentially through accelerated downregulation of cortactin stabilizing activity at Arp2/3-F-actin junctions. Importantly, CORO1B amplification and coronin 1B expression status may serve a role as a precision biomarker for identification of a subset of late-stage HNSCC patients that would benefit from more aggressive forms of initial clinical treatment.

Citation Format: Jessica L. Allen, Elyse L. Walk, Kristen L. Rhodes, Colleen J. Beatty, Steven M. Markwell, Brenen W. Papenberg, Erik T. Interval, Hong Wu, Marileila Varella Garcia, James E. Bear, Scott A. Weed. CORO1B amplification and expression status identifies an aggressive subset of chromosome 11q13 amplified HNSCC. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5064.
Abstract 5065: Role of EpCAM in EGFR signaling and tumorigenesis
Authors: Muhoro Lincoln , Fleming Timothy , Sankpal Narendra , Gillanders William
Published: July 2016

EpCAM is a transmembrane glycoprotein that functions as a homophilic cell adhesion molecule. EpCAM is expressed in normal epithelium and at even higher levels in epithelial cancers, including breast, pancreatic and lung cancers. Since its discovery in the 1980s, EpCAM has been targeted in several different epithelial cancers. Even though numerous novel therapeutic strategies targeting EpCAM have been investigated, the biological role and functional significance of EpCAM expression in cancer remains unclear. EpCAM expression appears to be associated with prognosis in several epithelial cancers -in some cancers it is associated with a favorable prognosis (renal cell, rectal) and in others it is associated with a poor prognosis (lung, pancreatic, breast). Thus, the function of EpCAM appears to be context-dependent in epithelial cancers. To understand the impact of EpCAM in human cancer, we specifically ablated EpCAM expression in over 40 cancer cell lines, and assessed the impact on invasion. We identified the A431 epidermoid cancer cell line as a cell line that overexpresses EpCAM, but is exquisitely sensitive to manipulation of EpCAM expression. A431 is known to overexpress EGFR and serves as a model cell line for EGFR signaling. Specific ablation of EpCAM significantly enhanced the migration and invasion of the A431 cell line. Specific ablation of EpCAM was also associated with increased EGFR activity, as demonstrated by phospho-immunoblot. Immunoprecipitation studies demonstrate that EpCAM binds directly to EGFR. Using specific EpCAM mutant constructs, we showed that the N-terminal domain of EpCAM is required for binding and suppression of EGFR activity. Using a soft agar colony growth assay, we were able to confirm that N-terminal EpCAM domain mutants (NTD288) inhibited colony growth in 3T3-transfected cells relative to the wildtype. In addition, a transformation assay showed that the same N-terminal mutant was able to inhibit transformation of 3T3 cells. To assess the effects of EpCAM ablation on in vivo tumor growth, we specifically ablated EpCAM and then performed tumor challenge experiments using immunocompromised mice. Specific ablation of EpCAM increased tumor growth relative to control. These data suggest that EpCAM may modulate EGFR signaling. Further studies are ongoing to define the mechanisms by which EpCAM inhibits EGFR activity.

Citation Format: Lincoln Muhoro, Timothy Fleming, Narendra Sankpal, William Gillanders. Role of EpCAM in EGFR signaling and tumorigenesis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5065.
Abstract 5067: Casein kinase 2 alpha phosphorylation of cortactin governs actin cytoskeletal regulation of invadopodia function
Authors: Markwell Steven M. , Gatesman Ammer Amanda , Interval Erik T. , Schafer Dorothy A. , Hames River A. , Weed Scott A.
Published: July 2016

Malregulation of signal transduction events controlling cortical actin cytoskeleton dynamics is responsible for to enhancing tumor cell motility and invasion. The actin-binding protein cortactin facilitates branched actin network formation through activation of the actin related protein (Arp) 2/3 complex. Increased cortactin expression due to gene amplification is observed in many cancers, corresponding with increased tumor progression and poor patient outcome. In many cancer types, elevated Arp2/3 complex activation is responsible for driving increased migration and extracellular matrix (ECM) degradation by governing invadopodia formation and activity. While cortactin-mediated activation of Arp2/3 complex has been well established, the objective of this study is to identify upstream signaling pathways responsible for modulating the interaction between cortactin and Arp2/3 complex in invasive carcinoma cells. We have determined that casein kinase (CK) 2α is responsible for disrupting the ability of cortactin to bind and/or activate Arp2/3 complex. CK2α directly phosphorylates cortactin at a conserved threonine 24 (T24) adjacent to the canonical Arp2/3 binding motif in the cortactin amino-terminal acidic (NTA) domain. CK2α phosphorylation of cortactin T24 impairs the ability of cortactin to activate Arp2/3 actin nucleation as determined by spectrofluorometric analysis. Decreased invadopodia formation and ECM degradation activity is observed in head and neck squamous cell carcinoma (HNSCC) cells with shRNA-mediated CK2α knockdown, expression of a CK2α phosphorylation-null cortactin mutant (T24A), and with treatment of the Phase I CK2α inhibitor CX-4945 (Silmitasertib). Collectively, these data suggest that CK2α-mediated cortactin phosphorylation at T24 is a critical event in regulating the interaction with Arp2/3 complex, identifying a key anti-invasive mechanism impacted by targeted anti-CK2α therapeutics.

Citation Format: Steven M. Markwell, Amanda Gatesman Ammer, Erik T. Interval, Dorothy A. Schafer, River A. Hames, Scott A. Weed. Casein kinase 2 alpha phosphorylation of cortactin governs actin cytoskeletal regulation of invadopodia function. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5067.
Abstract 5071: Expression and cellular distribution of Profilin1/VASPp157 and cofilin1/VASPp239 is altered by docosahexaenoic acid and suppresses cancer cell migration and survival
Authors: Ali Mehboob , Heyob Kathryn M. , Rogers Lynette K.
Published: July 2016

The major risk factor for cancer associated death is uncontrolled metastasis and longer cancer cell survival. Mechanisms associated with actin binding protein-mediated actin dynamics and subcellular distributions are not well defined. Secondary messengers (cAMP and cGMP)differentially phosphorylate actin binding proteins like VASP and are associated with actin remodeling in cancer cells. We tested the hypothesis that differential phosphorylation of VASP precipitates association with two additional actin binding proteins, profilin1 and cofilin1. Furthermore, we speculate that the associations of VASP with profilin1 or cofilin1 are causing changes in subcellular location of the protein complexes. Briefly, non-invasive lung epithelial (MLE12) and cancer (A549) cells were treated with 8-Br-cAMP and/or DHA for 6h and 24h. Actin binding proteins (profilin1, cofilin1, VASP, VASPp157and VASPp239) expressions were analyzed by western blot in cell lysate. Wound assay and transwell apparatus were used to study cell migration. Confocal analysis was performed to analyze F-actin content and actin binding proteins at the wound leading edges and in human lung cancer biopsy samples. Flow cytometry, using ki-67, and cleaved-caspase-3 antibodies were performed to study proliferation and cell viability. Our data indicate an association between profilin1/VASPp157 and cofilin1/VASPp239 and changes in the relative cytoplasmic/nuclear distribution of these protein complexes that coincide with the invasive potential of the cell line or tissue. Additional studies showed that docosahexaenoic acid, inhibited cancer cell migration and viability and altered the expression and cellular distribution of profilin1/VASPp157 and cofilin1/VASPp239. In summary, profilin1/VASPp157 and cofilin1/VASPp239 protein complex expression and subcellular distribution could serve as novel, new areas of research, as biomarkers of disease progression, and/or as innovative therapeutic targets against metastasis.

Citation Format: Mehboob Ali, Kathryn M. Heyob, Lynette K. Rogers. Expression and cellular distribution of Profilin1/VASPp157 and cofilin1/VASPp239 is altered by docosahexaenoic acid and suppresses cancer cell migration and survival. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5071.
Abstract 5075: Hedgehog Pathway Transcription Factor Gli1 Promotes Glioma Invasiveness through Up-regulating Aquaporin 1
Authors: Yao Zhenzhen , Yang Chaoxu , Ma Lie , Tan Yexiong
Published: July 2016

Gliomas, especially Glioblastoma multiformes (GBMs) express increased aquaporin1(AQP1) compared to normal brain. AQPs may contribute to brain edema, cell motility, and tumor angiogenesis. Although the physiology of AQP1 has been the subject of several publications, much less is known about the trans-acting factors involved in the control of AQP1 gene expression and the relationship between the regulation of the AQP1 expression and the major intracellular signaling pathways is also poorly concerned. Hedgehog signaling pathway activation is required for sustained glioma growth and survival. playing an important role in the genesis of glioma and In the present study, we report that Gli1, the transcriptional activator of the Hedgehog pathway, is co-expressed with AQP1 in human glioma tissues and can enhance AQP1 gene transcription by binding to conserved core Gli-binding site in the 5’-flanking promoter region of the AQP1. Transfection of 293T and U251 (human glioblastoma cell line) with Gli1 can markedly increase the AQP1 promoter reporter activity and the AQP1 expression level. Moreover, suppressing the Gli1 expression with the specific RNAi can abort this effect. The ChIP and reporter mutation analysis showed that the -406∼-398 region of the AQP1 promoter is essential for regulation activity of Gli1. To elucidate the possible pathophysiological importance of this molecular interaction, we investigated the migration and invasion ability of cell lines expressing different levels of Gli1 and AQP1. The results demonstrated that restoring the AQP1 expression in the Gli1-knockdown cell line can abort the decrease in the migration ability, which suggested that Gli1 may contribute to the invasion ability of glioma cells through AQP1. The up-regulation of Gli1 and its consequences of increased AQP1 in gliomas may provide a new therapeutic target, either as a cell surface marker or as a functional intervention.

Citation Format: Zhenzhen Yao, Chaoxu Yang, Lie Ma, Yexiong Tan. Hedgehog Pathway Transcription Factor Gli1 Promotes Glioma Invasiveness through Up-regulating Aquaporin 1. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5075.
Abstract 5078: Tumor treating fields (TTFields) reduce migration and invasion properties of human glioma cancer cells in vitro
Authors: Schneiderman Rosa S. , Shteingauz Anna , Giladi Moshe , Voloshin Tali , Porat Yaara , Munster Mijal , Blat Roni , Kirson Eilon D. , Weinberg Uri , Palti Yoram
Published: July 2016

The ability of glioblastoma cells to invade adjacent brain tissue remains one of the major obstacles in obtaining therapeutic success. The development of novel treatment modalities that hinder glioma cancer cell motility could therefore facilitate disease control. TTFields are an effective treatment modality delivered via continuous, noninvasive application of low intensity, intermediate frequency, alternating electric fields. This therapy is approved for the treatment of patients with glioblastoma. Previous investigations have shown that TTFields disrupt microtubules and septin filaments, both of which govern key roles in mitosis. The goal of this study was to evaluate the possible effect of TTFields on human glioma cell migration and invasion properties. Four human glioma cell lines: U-87 MG, A-172, LN-229, and LN-18 (ATCC, USA) were treated with TTFields (1.75 V/cm RMS, 200 kHz) for 24 hours using the inovitro system. Cell migration was measured using in vitro wound healing assays. These were analyzed with Image Pro Premier (Media Cybernetics, USA) to determine migration rates. Invasion assays were performed using modified Matrigel coated Boyden chamber. Cells were stained, photographed and counted using image J (NIH, USA).

Application of TTFields in-vitro led to a significant reduction in both migratory and invasive phenotype in all tested cell lines. Specifically, cell migration velocity, as assessed by the wound healing assay, was significantly reduced in U-87 MG (60%, P<0.001), and in A-172 (33%, P<0.001) compared with untreated control cells. The number of invading cells, as assessed by the modified Boyden chamber assay, was reduced in U-87 MG (54%, P<0.01), A-172 (51%, P<0.001), LN-229 (52%, P<0.001) and in LN-18 (30%, P<0.001) compared with untreated control cells.

Our results suggest that human glioma cell motility is impaired by exposure to TTFields. Further studies are needed to elucidate the mechanism by which TTFields disrupts cellular motility in glioma cancer cells.

Citation Format: Rosa S. Schneiderman, Anna Shteingauz, Moshe Giladi, Tali Voloshin, Yaara Porat, Mijal Munster, Roni Blat, Eilon D. Kirson, Uri Weinberg, Yoram Palti. Tumor treating fields (TTFields) reduce migration and invasion properties of human glioma cancer cells in vitro. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5078.
Abstract 5092: CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion
Authors: Zhou Pengcheng , Erfani Sonia , Segal Rosalind , Horbinski Craig , Yang Xiuwei H.
Published: July 2016

Glioblastoma, one of the most aggressive forms of brain cancer, is featured by high tumor cell motility and invasiveness, which not only fuel tumor infiltration, but also enable escape from surgical or other clinical interventions. Thus, better understanding of how these malignant traits are controlled will be key to the discovery of novel biomarkers and therapies against this deadly disease. Tetraspanin CD151 and its associated α3β1 integrin have been implicated in facilitating tumor progression across multiple cancer types. How these adhesion molecules are involved in the progression of glioblastoma, however, remains largely unclear. Here, we examined an in-house tissue microarray-based cohort of 96 patient biopsies and TCGA dataset to evaluate the clinical significance of CD151 and α3β1 integrin. Functional, biochemical and signaling analyses were also conducted to understand how these molecules promote the aggressiveness of glioblastoma at molecular and cellular levels. Results from our analyses showed that CD151 and α3 integrin were significantly elevated in glioblastomas at both protein and mRNA levels, and exhibited strong inverse correlation with patient survival (p <0.006). These adhesion molecules also formed tight protein complexes and synergized with EGF/EGFR to accelerate tumor cell motility and invasion. Furthermore, disruption of such complexes enhanced the survival of tumor-bearing mice in a xenograft model, and impaired activation of FAK and small GTPases. Also, knockdown- or pharmacological agent-based attenuation of EGFR, FAK or Graf (ARHGAP26)/small GTPase-mediated pathways markedly mitigated the aggressiveness of glioblastoma cells. Collectively, our findings provide clinical, molecular and cellular evidence of CD151-α3β1 integrin complexes as promising prognostic biomarkers and therapeutic targets for glioblastoma.

Citation Format: Pengcheng Zhou, Sonia Erfani, Rosalind Segal, Craig Horbinski, Xiuwei H. Yang. CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5092.
Abstract 5098: In vitro designer microenvironments for modeling the endothelin axis in brain cancer
Authors: Rizzi Simone C. , Mermier Charlotte , Crettaz Sophie , Blumer-Nesca Valeria , Gandar. Céline
Published: July 2016

Preclinical studies in vivo have demonstrated that the endothelin (ET) axis is implicated in drug resistance of several tumors (e.g. brain and ovarian). Indeed, antagonists, blocking the binding of endothelin-1 to endothelin receptors (ETRs) overexpressed by cancer cells, have shown to make tumors more sensitive to conventional chemotherapies. In vitro, however, mechanistic studies have been hampered by the lack of adequate models, in which cell lines sufficiently express all key elements of the ET axis (e.g. ETRs), as they do in xenografts.

We argue that limitations of conventional in vitro systems are mainly due to their inability to take into account the role of the extracellular microenvironment (ME). To overcome these limitations we have exploited the design flexibility of the QGel Matrix technology to identify 3D cell microenvironments that induced cancer cells to naturally express ETRs in vitro. Briefly, brain cancer cells LN229 were grown clonogenically in differently functionalized poly(ethylene glycol) (PEG)-based gels whose biological and biophysical characteristics were combinatorially varied. AlamarBlue™ assays and intracellular calcium release measurements (ICRM) were employed to measure cell growth and functionality of ETRs in the different gel ME over time. All assays were performed in 384-well plate format with liquid handling devices.

ETR expression and functionality was confirmed in control cell lines when grown as clonogenic spheroids in MEs or as monolayer on tissue culture plastic (2D). Likewise, LN229 growth was observed in all tested MEs and in 2D. However, ETR functionality of LN229 differed considerably depending on the ME. For instance, in 2D, ICRM did not show ETR functionality. In contrast, clonogenically grown cell spheroids, in gel MEs containing cell integrin binding sites, showed significantly higher ETR functionality compared to LN229 in control gel MEs. Ongoing studies are further investigating the influence of other matrix characteristics (stiffness and degradability) to optimise expression and functionality of ETRs by LN229 for drug testing applications.

These data suggest that engineered MEs are powerful tools for the development of cell-based assays with enhanced physiological relevance. With their proven compatibility with standard laboratory automation systems and assay miniaturization, these in vitro disease models can be translated to industry for making more relevant decisions on compound efficacy in preclinical tests.

Citation Format: Simone C. Rizzi, Charlotte Mermier, Sophie Crettaz, Valeria Blumer-Nesca, Céline Gandar. In vitro designer microenvironments for modeling the endothelin axis in brain cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5098.
Abstract 5103: Crosstalk between osteoprotegerin (OPG), fatty acid synthase (FASN), and cyclooxygenase-2 (COX-2) in breast cancer: implications in carcinogenesis
Authors: Goswami Sudeshna , Sharma-Walia Neelam
Published: July 2016

The cross-talk between malignant and nonmalignant cells in the tumor microenvironment, as maneuvered by cytokines/chemokines, drives breast cancer progression. We demonstrated that OPG is expressed and secreted at very high levels from the highly invasive breast cancer cell lines SUM149PT and SUM1315MO2 as compared to human normal mammary epithelial HMEC cells (1). OPG was involved in modulating aneuploidy, cell proliferation, and angiogenesis in breast cancer (1). Mass spectrometry analysis performed in this study revealed OPG interacts with fatty acid synthase (FASN), which is a key enzyme of the fatty acid biosynthetic pathway in breast cancer cells. Further, electron microscopy, immunofluorescence, and fluorescence quantitation assay highlighted the presence of a large number of lipid bodies (lipid droplets) in SUM149PT and SUM1315MO2 cells in comparison to HMEC. We recently showed upregulation of COX-2 inflammatory pathway and its metabolite PGE2 secretion in SUM149PT and SUM1315MO2 breast cancer cells (2). Interestingly, human breast cancer tissue samples displayed high expression of OPG, PGE2 and FASN. Immunofluorescence staining exposed the co-existence of COX-2 and FASN in the lipid bodies of breast cancer cells. We reasoned that there might be cross-talk between OPG, FASN, and COX-2 that sustains the inflammatory pathways in breast cancer. Here, we identified cis-acting elements involved in the transcriptional regulation of COX-2 and FASN by recombinant human OPG (rhOPG). Treatment with FASN inhibitor C75 decreased the number of lipid body/cell, downregulated phosphorylation of ERK, GSK3β, and induced apoptosis by caspase-3 and caspapse-9 activation. Collectively, the novel biological cross-talk between OPG, FASN, and COX-2 advocates for combinatorial drug treatment to block these players of carcinogenesis as a promising therapeutic to target highly invasive breast cancer.

References:

1. Goswami, S., & Sharma-Walia, N. (2015). Osteoprotegerin secreted by inflammatory and invasive breast cancer cells induces aneuploidy, cell proliferation and angiogenesis. BMC. http://www.biomedcentral.com/1471-2407/15/935

2. Chandran, K., Goswami, S., & Sharma-Walia, N. (2015). Implications of a peroxisome proliferator-activated receptor alpha (PPARα) ligand clofibrate in breast cancer. Oncotarget, 5. http://www.impactjournals.com/oncotarget/index.php?journal = oncotarget&page = article&op = view&path%5B%5D = 6402

Citation Format: Sudeshna Goswami, Neelam Sharma-Walia. Crosstalk between osteoprotegerin (OPG), fatty acid synthase (FASN), and cyclooxygenase-2 (COX-2) in breast cancer: implications in carcinogenesis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5103.
Abstract 5109: MDM2 regulates intracellular pathways in TNBC and osteosarcoma that affect osteoclastogenesis
Authors: Olivos David J. , Mayo Lindsey D.
Published: July 2016

Advanced cancer cells infiltrate and colonize new organ microenvironments through transformation of the dynamic metastatic niche. In bone, tumor cells secrete soluble factors that distort and manipulate normal bone remodeling leading to osteolytic lesions and inflammation. Clinically, primary high-grade bone sarcomas and secondary metastatic cancers exhibit elevated levels of murine double minute 2 (Mdm2), the principal cellular antagonist and E3 ubiquitin ligase of tumor suppressor p53. We demonstrate a novel function of mdm2, independent of p53, to drive osteolytic disease influenced by the signaling cascade of RANKL, ICAM1, and RANTES. To elucidate the direct influence of Mdm2 in cancer cells on osteoclast differentiation, several cell lines were created to overexpress or silence Mdm2. We found that osteoblast-like osteosarcoma (MG63, Saos2) and metastatic breast cancer cell lines (MDA468, MDA231, TMD-231, T47D, and BT474) lead to significant increased osteoclast differentiation, proliferation, and bone resorption. Co-cultures of Mdm2 over-expressing cancers and normal monocytes resulted in increased numbers of osteoclasts. In cancer cell lines where Mdm2 is silenced, we observed lower number of osteoclasts. The presence of Mdm2 in cancer cells also increased osteoclast resorption in an in vitro organ model. To determine the effects of ICAM1, we used an ICAM antibody to block ICAM1 in the media and showed a decrease in osteoclastogenesis. Understanding the role of Mdm2 in osteoclastogenesis may be amendable to translational benefit in disease models of advanced bone resorption and bone metastases.

Citation Format: David J. Olivos, Lindsey D. Mayo. MDM2 regulates intracellular pathways in TNBC and osteosarcoma that affect osteoclastogenesis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5109.
Abstract 5114: The role of microvesicles on immune function in response to cancer
Authors: Jaiswal Ritu , Pokharel Deep , Bebawy Mary
Published: July 2016

Cell to cell communication is vital for the co-ordination of physiological process and the regulation of an organism's phenotype. More recently communication via extracellular membrane vesicles has gained recognition. We first described a novel mechanism for the spread and dominance of multidrug resistance (MDR) and enhanced metastatic capacity in cancer via submicron microparticles (MPs). MPs are plasma membrane vesicles released spontaneously from various cell types, carrying bioactive material and are implicated in different physiological and pathophysiological processes. Through this communication apparatus, cancer cells can acquire and secure a survival advantage by various mechanisms. This study aims to examine a role of MPs in altering immune cell function in cancer.

The effects of MPs isolated from human breast cancer cells were examined on antigen presenting cells (APC) in vitro. MP-mediated effects on cell phenotype and functionality was assessed by cytokine profiling and migration assay. We observed a cancer cell induced change in immune cell phenotype and functionality which have the potential to support a reduced global immune response in cancer. The elucidation of this pathway provides novel therapeutic strategies which can be exploited for the treatment of cancer.

Citation Format: Ritu Jaiswal, Deep Pokharel, Mary Bebawy. The role of microvesicles on immune function in response to cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5114.
Abstract 512: KRAS mutation in cell-free DNA was correlated with treatment response to gemcitabine/cisplatin chemotherapy in patients with pancreatic cancer
Authors: Kim Min Kyeong , Kyong-Ah Yoon , Sang Myung Woo , Yun Hee Kim , Sang Jae Park , Sun-Young Kong
Published: July 2016

Cell-free DNA (cfDNA) of cancer patients has been known to be a useful marker for minimal residual disease detection and treatment monitoring. However, there are a few studies which showed correlation of cfDNA with pancreatic cancer treatment. Here we investigated applicability of cfDNA as a response and prognosis biomarker through comparing the qualitative and quantitative changes of the KRAS mutant in the patients with pancreatic cancer before and after treatment.

Total of 44 pancreatic cancer patients who treated by gemcitabine and cisplatin included in the study. Serum from the blood samples was separated by centrifugation through the method established. cfDNA was extracted through the QIAamp Circulating Nucleic Acid Kit (Qiagen, Germany) from 0.8 ml of serum. Extracted cfDNA was quantified using the Qubit dsDNA HS Assay Kit (Thermo Fisher Scientific, USA). QX200 Droplet Digital PCR System (Biorad, USA) was applied to measure frequency of KRAS mutation. We performed digital PCR with KRAS screening multiplex droplet digital PCR kit which covers G12A, G12C, G12D, G12R, G12S, G12V and G13D sites (Biorad, USA). Mutant concentration and fractional abundance were analyzed by QuantaSoft software (Biorad, USA).

The positive rate of KRAS mutation was 61% (27/44) and 47% (16/34) in before and after treatment. When we analyzed the treatment response according to the positive presence of KRAS mutation before treatment, 50% and 61% of KRAS mutations were observed in patients who showed either partial response (PR) or stable disease (SD) after chemotherapy, respectively. However, all the 5 patients (100%) with progressive disease (PD) showed KRAS mutation implicating significant correlation (p = 0.046) with treatment response.

The fraction change of KRAS mutation was showed decrease in 18 (58.1%) patients and increase in 13 (41.9%) patients comparing before and after treatment status. When we observed the association the fraction change direction (decrease vs. increase) with the survival, there was no significant difference.

These results implicate that KRAS mutation in cell-free DNA might be associated with treatment response to gemcitabine/cisplatin chemotherapy. In further studies, we will conduct in prospective study for pancreatic cancer patients. (This study was supported by National cancer center, Korea, Grant no. 1510203-1)

Citation Format: Min Kyeong Kim, Yoon Kyong-Ah, Woo Sang Myung, Kim Yun Hee, Park Sang Jae, Kong Sun-Young. KRAS mutation in cell-free DNA was correlated with treatment response to gemcitabine/cisplatin chemotherapy in patients with pancreatic cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 512.
Abstract 5121: Immunomodulating cytokine profiling of docetaxel-treated human prostate cancer specimens
Authors: Mehrotra Debapriya G. , Brijwani Nilesh , Tewary Biplab , Sekar Vasathkumar , Krishnan Abhishek , Pinto Dency D. , Oliyarasi Muthusamy , Majumder Biswanath , Thiyagarajan Saravanan , Radhakrishnan Padhma , Majumder Pradip K.
Published: July 2016

Prostate cancer is one of the leading malignancies in adult males worldwide and existing therapies often result in treatment failure and emergence of castration resistant prostate cancer (CRPC). Outcome of some recent clinical trials highlighted the benefit of Docetaxel as a part of initial therapy in CRPC. However, a significant number of patients still remain chemoresistant. Context dependent response profiling using a clinically oriented functional platform would further improve this scenario. Here, we elucidated the role of different immune cells and type 1 and type 2 cytokines in improving Docetaxel sensitivity to prostatic carcinoma. We tested Docetaxel sensitivity in prostate tumors (n = 10) using CANScriptTM platform, a personalized next generation functional testing tool (Majumder B et al. Nat. Commun 2015, Goldman A et al. Nat. Commun. 2015). Of these 10 tumors, 4 were found to be sensitive to Docetaxel and 6 were insensitive. The immune profiling of these tumors suggested that despite preferential CD45, CD8 and CD4 levels in majority of the responders both responders and non responders display modest numbers at baseline. We also observed similar heterogeneity in CD69 (T cell activation marker) in these two groups. Altered expression of cytokines was observed in Docetaxel sensitive and resistant tumors upon their co-culture with peripheral blood mononuclear cells (PBMC), suggesting a defined role of these cytokines in Docetaxel response. We extended the study further by testing the efficacy of PD-1/ PD-L1 inhibitors in Docetaxel resistant tumors. Our results provide the basis for validation of immune phenotypes and cytokines as therapeutic response biomarkers in Docetaxel treated prostatic tumors.

1. Majumder B et al. Nat. Commun.6:6169 (2015).

2. Goldman A et al. Nat. Commun. 6:6139 (2015).

Citation Format: Debapriya G. Mehrotra, Nilesh Brijwani, Biplab Tewary, Vasathkumar Sekar, Abhishek Krishnan, Dency D. Pinto, Muthusamy Oliyarasi, Biswanath Majumder, Saravanan Thiyagarajan, Padhma Radhakrishnan, Pradip K. Majumder. Immunomodulating cytokine profiling of docetaxel-treated human prostate cancer specimens. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5121.
Abstract 5125: Immunomodulatory activity of bitter melon extract in head and neck squamous cell carcinoma
Authors: Bhattacharya Sourav , Steele Robert , Muhammad Naoshad , Peng Guangyong , Ray Ratna B.
Published: July 2016

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer and leading cause of cancer related mortality worldwide. Despite the advancement in treatment procedures the overall survival rate of patients has not considerably enhanced in the past few decades. Therefore, new strategies to achieve a favorable response for the improvement in the prognosis of HNSCC are urgently needed. In this study we examined the immune modulatory activity of bitter melon extract (BME) in HNSCC tumor microenvironment. For this, mouse head and neck cancer (SCCVII) cells were subcutaneously injected into the flanks of C3H mice. BME was fed orally, and tumor growth was evaluated. We observed that BME treatment significantly inhibits the tumor growth in BME fed mice as compared to control group. Flow cytometry data showed that BME treatment not only decreases the infiltrating T regulatory (Treg) cells in the tumor but also in splenocytes. Additionally, BME treatment reduces Th17 cell population in the tumor and augments in the spleen. However, BME treatment did not alter Th1 and Th2 populations. Further study suggested that BME inhibits cell proliferation as evident from low expression of PCNA and c-Myc in the tumors of BME fed mice as compared to that of control group. To our knowledge, this is the first report showing BME exerts immunomodulatory effect in regressing HNSCC tumor growth in preclinical model.

Citation Format: Sourav Bhattacharya, Robert Steele, Naoshad Muhammad, Guangyong Peng, Ratna B. Ray. Immunomodulatory activity of bitter melon extract in head and neck squamous cell carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5125.
Abstract 5128: Characterization of tumor immune microenvironment in response to PD-L1 therapy initiated at different time points post inoculation in syngeneic mouse models
Authors: Sharma Geeta , Wu Susan , Mihalek Robert , Fiore Ann , Gale Matthew , Dias Christa , Grant Wendy , Hernandez Nidia
Published: July 2016

The tumor microenvironment is an important aspect of cancer biology that contributes to tumor initiation, progression and responses to therapy. Cells and molecules of the immune system are fundamental components of the tumor microenvironment which have been known to vary widely and are important in determining the anti-tumor immune response. The approval of immune checkpoint inhibitors like PD-1 and CTLA-4 antibodies has resulted in a lot of research activity in immune-oncology. Syngeneic mouse models have been utilized to understand the preclinical immune response as a surrogate to the clinical response. The timing of immune checkpoint inhibitor dosing is supposed to play an important role on the tumor growth in mouse models. In order to understand the correlation of tumor regression, survival and immune response in a preclinical mouse model, we evaluated the effect of different times of treatment initiation with Program Death Ligand-1 (PD-L1) on tumor volume, survival and tumor infiltrating leukocytes (TIL’s). Various dosing regimens evaluated included initiation of PD-L1 therapy on the day of inoculation, 6 and 12 days post inoculation. Tumors were collected from three different syngeneic mouse models (CT26, RENCA and B16F10) and profiled for the presence of tumor infiltrating leukocytes (TIL’s) using flow cytometry. Major sub-population of TIL's examined included T-regulatory cells (Treg’s), Tumor Associated Macrophages (TAM’s) and Myeloid Derived Suppressor Cells (MDSC’s). Finally, an attempt was made to identify any correlation or lack thereof between tumor growth and tumor immune microenvironment.

Citation Format: Geeta Sharma, Susan Wu, Robert Mihalek, Ann Fiore, Matthew Gale, Christa Dias, Wendy Grant, Nidia Hernandez. Characterization of tumor immune microenvironment in response to PD-L1 therapy initiated at different time points post inoculation in syngeneic mouse models. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5128.
Abstract 5139: Adjuvant immunotherapy targeting CSF1R to limit metastatic progression
Authors: Evans Justin , Giles Amber J. , Murgai Meera , Kasai Miki , Reid Caitlin , Kaplan Rosandra Natasha
Published: July 2016

Metastasis is often considered a late stage event, although the first changes in the metastatic site occur very early during localized primary tumor development. Although understanding of these initiating events is limited, immune suppression plays an essential role in allowing for the outgrowth of disseminating tumor cells. Targeting this immune suppressive milieu can hold promise to effectively inhibit metastatic progression. Colony stimulating factor-one (CSF-1) is overexpressed by many diverse tumor types and can induce expansion and recruitment of CSF-1 receptor (CSF-1R) expressing cells. CSF-1R is expressed on a multitude of myeloid cells including inflammatory monocytes, myeloid derived suppressor cells and macrophages, which are key immune suppressive cells in a primary tumor site. Using a metastatic rhabdomyosarcoma model, we have identified expansion of immune suppressive myeloid cells in the early metastatic microenvironment. PLX3397, which is small molecular inhibitor that selectively targets CSF-1R, Kit and Oncogenic FLT3, was used to determine the impact of targeting this immune suppressive microenvironment in limiting metastatic progression. PLX3397 and GW2580, a selective CSF1R inhibitor, reduce the immune suppressive capacity of bone marrow-derived monocytes on activated T cells. Adjuvant therapy with PLX3397 in resected rhabdomyosarcoma reduces metastatic spread. Targeting CSF-1R is associated with an expansion of CD11C expressing antigen presenting cells in the metastatic tissue and in combination with PD-1 blockade improves anti-tumor immunity. Continued investigation of combination immunotherapy with metastatic microenvironment targeting in the adjuvant setting holds promise to limit metastatic spread.

Citation Format: Justin Evans, Amber J. Giles, Meera Murgai, Miki Kasai, Caitlin Reid, Rosandra Natasha Kaplan. Adjuvant immunotherapy targeting CSF1R to limit metastatic progression. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5139.
Abstract 5141: Determinants of metastatic competence in breast carcinoma: a role for immune cells
Authors: Joseph Robiya , Soundararajan Rama , Paranjape Anurag , Mani Sendurai
Published: July 2016

Dynamic interactions between cancer cells and their surrounding microenvironment influence tumor survival, growth and metastasis. The tumor microenvironment harbors a complex variety of cells including T lymphocytes and macrophages that produce a host of cytokines, chemokines, growth factors or interleukins, all of which presumably work in coordination to determine net tumor biology. Immune cells can offer a critical check-point in tumor progression. Interestingly however, infiltration of the tumor by immune cells appears to have dual functionality - they can reportedly either be pro-metastatic or anti-metastatic in their contribution. These clearly conflicting roles of immune cells limit our comprehension of their actual input to tumor advancement. Tumor infiltrating lymphocytes, in particular, the infiltration by T cells, has emerged as a good prognostic marker for a variety of cancers. However, the key molecular factors that regulate the cross-talk between tumor cells and T lymphocytes, and the underlying signaling pathways are still ill-defined. Moreover, the impact of T lymphocytes of the inflammatory tumor microenvironment, on the epithelial-mesenchymal plasticity and associated metastatic traits in breast cancer cells, is incompletely understood. We previously demonstrated that two key EMT/CSC factors - FOXC2 and Twist - are critical requirements for breast carcinoma cells to metastasize. The objective of the current study is to systematically investigate the role of regulatory T cells in EMT/CSC-dictated breast tumor progression, using two isogenic breast cancer cell lines (67NR and 4T1) that form primary mammary tumors similarly, but differ drastically in their ability to metastasize.

Citation Format: Robiya Joseph, Rama Soundararajan, Anurag Paranjape, Sendurai Mani. Determinants of metastatic competence in breast carcinoma: a role for immune cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5141.
Abstract 5153: Dual inhibition of STAT3 and IL-8 pathways as a novel therapeutic approach in osteosarcoma
Authors: Cao Yang , Xiao Hui , Wu Xiaojuan , Lin Jiayuh
Published: July 2016

Abstract

Objective: Targeting STAT3 signaling represents a potential therapeutic approach to treatment of osteosarcoma. However, the use of STAT3 inhibitor as a single agent may not be effective for cancer therapy. Identify the pathway(s) that may generate synergy in tumor suppression may be more effective in osteosarcoma therapy.

Methods: Inflammatory cytokines IL-6, IL-11, and IL-8 secretion of osteosarcoma after STAT3 inhibition were determined by ELISA assay. The sensitivity to STAT3 inhibitor was examined by cell viability assay. Cell migration and colony forming ability were evaluated when combination treatment.

Results: In this study, we observed that the levels of IL-11 were significantly decreased and IL-6 was slightly decreased by STAT3 inhibitor. Interestingly, IL-8 levels were increased upon STAT3 inhibition. IL-8 was originally discovered as one of the major chemokines associated with the promotion of neutrophil chemotaxis and inflammatory responses. Previous studies have demonstrated that IL-8 contributes to cancer progression through its induction of tumor cell proliferation, survival, migration, and angiogenesis. Knocking down IL-8 expression using RNA interference resulted in enhanced sensitivity to STAT3 inhibitor. ELISA assay showed that MEK inhibitor (AZD6244 or Trametinib) and P38α inhibitor (LY2228820) had the ability to reduce the levels of IL-8 induced by STAT3 inhibition. Combination treatment of STAT3 and with a MEK inhibitor or with a P38α inhibitor showed more effective cytotoxic effect on osteosarcoma cell lines compared to single agent alone. Furthermore, the combination treatment exhibited stronger inhibition of cell migration and colony forming ability than single agent alone.

Conclusion: These results suggest the IL-8 induction as a possible feedback mechanism for resistance to STAT3 inhibitor and suggest that simultaneous inhibition of STAT3 and IL-8 may be a more effective therapeutic approach in osteosarcoma.

Citation Format: Yang Cao, Hui Xiao, Xiaojuan Wu, Jiayuh Lin. Dual inhibition of STAT3 and IL-8 pathways as a novel therapeutic approach in osteosarcoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5153.