bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 3790: Circulating tumor cells at disease recurrence in patients with head and neck cancer after curative therapy
Authors: Hsieh Jason Chia-Hsun , Yeh Ting-Hsiuan , Wang Hung-Ming , Lin Yung-Chang , Lin Nina Ming-Jung , Ye Siou-Ru , Lee Jane Ying-Chieh , Wu Min-Hsien
Published: July 2017

Background: Circulating tumor cell (CTC) has been prognostic and predictive in numerous types of cancer; however, its role in early diagnosis of relapse remains unclear.

Methods: Eighty-six patients were prospectively enrolled between March 2015 and June 2016. Among these patients, 51 head and neck squamous cell carcinoma (HNSCC) patients had suspicious recurrent lesion(s), whilst 35 HNSCC patients were newly diagnosed. CTC test was performed by negative selection strategy and CD45-negative and EpCAM-positive cells were identified as CTCs. Biopsy on suspicious lesion(s) and CTC analysis were performed simultaneously. We analyzed the differences of CTC numbers among HNSCC patients with true recurrence, biopsy-negative and newly-diagnosed.

Results: Mean±standard deviation(SD) of CTC numbers in baseline at diagnosis (n=35), true recurrence (n=40) and biopsy-negative (n=11) groups were 41.98±32.02, 81.75±64.91 and 16.55±6.82 cells/mL, respectively. The difference of CTC numbers among three groups was significant (P <0.001). CTCs (mean±SD) among different failure types were 110.89±84.69, 105.67±50.77, 73.31±37.82 and 59.11±54.09 in lung metastasis, second primary tumor, extrapulmonary metastasis and locoregional recurrence respectively and significantly different (P = 0.049). Also, CTC numbers between first cancer (baseline at diagnosis) and second primary tumor were different (P = 0.004).

Conclusion: CTCs numbers are significantly higher in true recurrence than the biopsy-negative group when a patient had a lesion suspected to be a recurrence. CTC test may be useful to help distinguish true recurrence in HNSCC patients after curative therapy.

Citation Format: Jason Chia-Hsun Hsieh, Ting-Hsiuan Yeh, Hung-Ming Wang, Yung-Chang Lin, Nina Ming-Jung Lin, Siou-Ru Ye, Jane Ying-Chieh Lee, Min-Hsien Wu. Circulating tumor cells at disease recurrence in patients with head and neck cancer after curative therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3790. doi:10.1158/1538-7445.AM2017-3790
Abstract 3805: Pre-diagnostic statin use among breast cancer patients - the relation to HMG-CoA reductase expression and disease-free survival
Authors: Tryggvadottir Helga , Gustbée Emma , Markkula Andrea , Simonsson Maria , Nodin Björn , Jirström Karin , Rose Carsten , Ingvar Christian , Borgquist Signe , Jernström Helena
Published: July 2017

Background: The purpose of this study was to investigate whether pre-diagnostic statin use was associated with tumor expression of HMG-CoA reductase (HMGCR) and disease-free survival (DFS) in breast cancer. Previous studies have shown anti-carcinogenic properties of statins and a significantly longer survival among breast cancer patients using statins. We recently showed, that the target of statins, HMGCR, was up-regulated in breast cancer among patients preoperatively treated with statins in a window-of-opportunity trial.

Methods: A population-based cohort of primary breast cancer patients in Lund, Sweden was assembled between October 2002 and June 2012. Patients completed a questionnaire including information on medication use. Statin use in relation to DFS was analyzed in 985 patients. Tumor tissue microarrays were constructed and stained with a polyclonal HMGCR antibody to assess HMGCR expression (n=848).

Results: Patients were followed for up to 11 years (median follow-up time 5.0 years). In the present study, pre-diagnostic statin use was neither associated with HMGCR expression (P=0.53) nor with DFS (P=0.92), overall or separately in any of the HMGCR expression groups (negative, weak, moderate/strong). Moreover, statin use was not associated with clinical tumor characteristics (tumor size, axillary lymph node involvement, histological grade, hormone receptor status or HER-2 amplification).

Conclusion: In contrast to previous studies, the present study did not show any significant association between pre-diagnostic statin use and DFS. It is possible that patients who already used statins have developed tumors that are less dependent on cholesterol metabolism and consequently less influenced by statin treatment. The timing of statin use in relation to breast cancer diagnosis and prognosis should be evaluated in another cohort with preferably longer follow-up time.

Citation Format: Helga Tryggvadottir, Emma Gustbée, Andrea Markkula, Maria Simonsson, Björn Nodin, Karin Jirström, Carsten Rose, Christian Ingvar, Signe Borgquist, Helena Jernström. Pre-diagnostic statin use among breast cancer patients - the relation to HMG-CoA reductase expression and disease-free survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3805. doi:10.1158/1538-7445.AM2017-3805
Abstract 3821: Biochemical parameters of breast cancer patients in Nigeria
Authors: Udegbe Sandra A. , Oyinbo Atinuke G. , Akaiso Andiyenema N. , Nwaonumah Kingsley E. , Iweala Emeka Eze
Published: July 2017

Studies have revealed the importance of differential biochemical parameters of cancer patients in the development of critical biomarkers for accurate diagnosis and treatment. There is a dearth of information on the biochemical characteristics of breast cancer patients in Nigeria which may vary from other climes. The discovery of new biomarkers will provide a deeper understanding of the disease and wider scope of diagnosis and hence improvement in management of breast cancer. In this line of investigation, we examined some biochemical parameters including Alanine transaminase (ALT), Alkaline phosphatase (ALP), Low density lipoprotein (LDL), High density lipoprotein (HDL) and triglycerides (TRIG) in the plasma of 53 breast cancer patients and 14 controls. The data obtained indicates that there were no significant differences in the ALP, LDL and TRIG while ALT and HDL were significantly difference. This indicates the possible implication of ALT and HDL in breast cancer disease in Nigeria and their potential to be further developed into biomarkers for diagnosis.

Citation Format: Sandra A. Udegbe, Atinuke G. Oyinbo, Andiyenema N. Akaiso, Kingsley E. Nwaonumah, Emeka Eze Iweala. Biochemical parameters of breast cancer patients in Nigeria [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3821. doi:10.1158/1538-7445.AM2017-3821
Abstract 3826: Clinical validation of a serum protein panel (FLNA, FLNB and KRT19) for diagnosis and prognosis of prostate cancer
Authors: Ravipaty Shobha , Wu Wenfang , Dalvi Aditee , Tanna Nikunj , Andreazi Joe , Friss Tracey , Klotz Allison , Liao Chenchen , Garren Jeonifer , Schofield Sally , Diamandis Eleftherios P. , Klein Eric A. , Dobi Albert , Srivastava Shiv , Tekumalla Poornima , Kiebish Michael A. , Vishnudas Vivek K. , Sarangarajan Rangaprasad , Narain Niven R. , Akmaev Viatcheslav
Published: July 2017

Background: Prostate cancer (PrCa) is a leading cause of cancer deaths in males in the US. Current tests of prostate-specific antigen (PSA) screening and the diagnostic prostate biopsy are often inconclusive. Many patients with a PSA positive blood test often undergo invasive repeat biopsy procedures. Additionally, there is a need for diagnostic tests that differentiate between low and high-risk cancers. This study reports on the development of a novel serum protein panel of three PrCa biomarkers, Filamin A, Filamin B and Keratin-19 (FLNA, FLNB and KRT19) using multivariate models for disease screening and prognosis.

Methods: ELISA and IPMRM (LC-MS/MS) based assays were developed and analytically validated by quantitative measurements of the biomarkers in serum. Retrospectively collected and clinically annotated serum samples with PSA values and Gleason scores (GS) were analyzed from 503 subjects who underwent prostate biopsy, and showed no evidence of cancer with or without indication of prostatic hyperplasia, or had a definitive pathology diagnosis of prostatic adenocarcinoma. Probit linear regression models were used to combine the analytes into score functions to address the following clinical questions: does the biomarker test augment PSA for population screening? Can aggressive disease be differentiated from lower risk disease, and can the panel discriminate between benign prostate hyperplasia (BPH) and PrCa? Results: Table 1: Berg PrCa Panel AUC summary for the four clinical indications.

Conclusion: As shown in Table 1, modelling of the data demonstrated that the new PrCa biomarkers and PSA in combination were better than PSA alone in identifying PrCa, improved the prediction of high and low risk disease, and improved prediction of BPH versus PrCa.

Citation Format: Shobha Ravipaty, Wenfang Wu, Aditee Dalvi, Nikunj Tanna, Joe Andreazi, Tracey Friss, Allison Klotz, Chenchen Liao, Jeonifer Garren, Sally Schofield, Eleftherios P. Diamandis, Eric A. Klein, Albert Dobi, Shiv Srivastava, Poornima Tekumalla, Michael A. Kiebish, Vivek K. Vishnudas, Rangaprasad Sarangarajan, Niven R. Narain, Viatcheslav Akmaev. Clinical validation of a serum protein panel (FLNA, FLNB and KRT19) for diagnosis and prognosis of prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3826. doi:10.1158/1538-7445.AM2017-3826
Abstract 3828: The role of CK2 for overcoming paclitaxel resistance in gastric cancer
Authors: Jung Minkyu
Published: July 2017

Despite advances in cancer treatment, gastric cancer is still one of the most fatal cancers. This is because paclitaxel, the most widely used treatment for gastric cancer, has limited clinical utility by the development of resistance. Casein kinase 2 (CK2) activation has been reported to be involved in proliferation in various tumors and resistance form chemotherapy. Therefore, we investigated the association between paclitaxel resistance and CK2 activation. CK2 expression was evaluated by immunohistochemistry (IHC) on formalin-fixed, paraffin-embedded tumors from 59 AGC patients who were treated with paclitaxel as second line therapy. Patients with high expression of CK2 (29/59, 39%) showed lower disease control rate (DCR) (47.7 % vs. 72.3 %, p=0.017) and shorter progression free survival (PFS) (2.8 months vs. 4.8 months, p=0.009) compared to those who with low expression. Cell proliferation assay were carried out by MTT assay after drug treatment with paclitaxel, CX-4945 (CK2 inhibitor) in 49 gastric cancer cell lines. CK2 protein expression was shown to be associated with paclitaxel sensitivity. Of the gastric cancer cell lines, SNU-1 was selected for paclitaxel resistance, high expression of CK2, and high sensitivity to CX-4945. Combination therapy CX-4945 and paclitaxel showed synergistic antitumor effect in SNU-1 by MTT assay and showed inhibition of down signaling of PI3K/AKT pathway on western blot. In conclusion, CK2 activation was shown to be related to paclitaxel resistance. CX-4945 in combination with paclitaxel could be treatment of choice in gastric cancer with paclitaxel resistance.

Citation Format: Minkyu Jung. The role of CK2 for overcoming paclitaxel resistance in gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3828. doi:10.1158/1538-7445.AM2017-3828
Abstract 3832: Optimization strategy for fluorescent multiplex immunohistochemistry tissue staining
Authors: zheng Yi , Coltharp Carla , Dilworth Ryan , Liu Linying , Unfricht Darryn , Hoyt Cliff , Rajopadhye Milind , Miller Peter
Published: July 2017

Introduction: Recent insights into the tumor microenvironment have fueled the need for additional information beyond the one or two phenotypes provided by traditional immunohistochemistry (IHC). As a response, manual and automated fluorescent multiplex immunohistochemistry (fIHC) techniques have been recently developed and accepted by the immuno-oncology space. Fluorescent multiplex immunohistochemistry (fIHC) assays are designed to simultaneously measure multiple biomarkers in tissue sections with visual context that is lost in other methods, such as flow cytometry. Here we describe a novel optimization strategy to achieve quantitative, robust, and specific multiplex fIHC staining results with both manual and automated multiple-color Opal procedures.

Methods: Formalin-fixed paraffin-embedded samples of primary tumors were immunostained using Opal™ reagents both manually and on a fully automated Leica BOND RX™ stainer. The impact of different reagent concentrations and quantities were analyzed in respect to signal specificity and robustness, stripping efficiency, signal co-localization, signal to noise, and color separation. Images were acquired on a Vectra 3.0® automated imaging system, and analyzed with inForm® software.

Results: The goals of this study were two-fold:

-to understand the impact of Opal reagent concentrations/quantities on fluorescent signal intensities acquired from cells within the context of tissue.

-to develop an Opal reagent optimization method that yields more consistent, quantitative results from separated and co-localized fluorescent signals.

We’ve applied this novel fIHC experimental approach and optimization strategy to Opal monoplex and multiplex assays and explored staining robustness, contextual specificity, staining order independence, and co-localized signal separation. Using the novel optimization strategy, we have achieved optimal staining patterns with improved confidence in the quantitative characteristics of the assay. Tissue sections stained after optimization have exhibited staining order independence and closely align with traditional IHC patterns.

Conclusion: This novel optimization strategy, developed for Opal fIHC assays, is more quantitative, improves staining results, and minimizes interference between co-localized biomarkers.

Citation Format: Yi zheng, Carla Coltharp, Ryan Dilworth, Linying Liu, Darryn Unfricht, Cliff Hoyt, Milind Rajopadhye, Peter Miller. Optimization strategy for fluorescent multiplex immunohistochemistry tissue staining [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3832. doi:10.1158/1538-7445.AM2017-3832
Abstract 3878: Musashi-2 (MSI2) regulation of ERBB family proteins in non-small cell lung cancer (NSCLC)
Authors: Kudinov Alexander , Deneka Alexander , Nikonova Anna N. , Nicolas Emmanuelle , Korobeynikov Vladislav A. , Serebriiskii Ilya G. , Karanicolas John , Golemis Erica A. , Boumber Yanis
Published: July 2017

The purpose of this study is to establish whether a new signaling axis we recently described can be targeted to improve patient survival in lung cancer, one of the leading causes of death worldwide, with over 1.6 million deaths annually. Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. A small number of targeted therapies have been shown to be useful in lung cancer, including inhibitors of EGFR, but these are typically only active in a subset of tumors that maintain epithelial characteristics. Musashi-2 (MSI2), an RNA-binding protein that regulates mRNA translation, has been linked to maintenance of a stem cell state in multiple hematologic and solid tumor malignancies. We recently established (Kudinov et al, PNAS 2016, PMID:27274057) that MSI2 is elevated in a subset of NSCLC tumor upon progression and drives NSCLC metastasis, in part based on activity supporting a TGF-beta/SMAD3/claudin signaling cascade that enhances epithelial-mesenchymal transition (EMT). Using reverse phase protein array (RPPA) analysis of MSI2-depleted versus control KrasLA1/+;P53R172HΔG/+ murine NSCLC cell line models identified a significant 2.7-fold upregulation of HER3 upon MSI2 depletion. Negative MSI2-dependent regulation of ERBB3 protein expression was confirmed in multiple additional murine and human KRAS-dependent NSCLC models, based on analysis of MSI2 depletion or overexpression. In contrast, MSI2 positively regulated expression of the EGFR/ERBB1 protein in the same models. In detailed analysis, we have addressed the mechanism by which MSI2 regulates expression of the ERBB group of receptor tyrosine kinases. In addition, these data suggested the hypothesis that MSI2 expression might predict response to EGFR-targeted inhibitors, and that dual targeting of MSI2 and EGFR might be therapeutically valuable. We will present data on the activity of EGFR inhibitors in the context of depleted or elevated MSI2 expression, and the effect of combining inhibition of EGFR with recently developed MSI2 inhibitors. In summary, these results for the first time indicate a role of MSI2 in supporting EGFR expression in NSCLC and suggest that MSI2 may drive NSCLC development and progression in part via EGFR, and may modulate response to EGFR-targeted agents.

Citation Format: Alexander Kudinov, Alexander Deneka, Anna N. Nikonova, Emmanuelle Nicolas, Vladislav A. Korobeynikov, Ilya G. Serebriiskii, John Karanicolas, Erica A. Golemis, Yanis Boumber. Musashi-2 (MSI2) regulation of ERBB family proteins in non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3878. doi:10.1158/1538-7445.AM2017-3878
Abstract 3892: Delineating the role of ZEB1 loss in the chemo and radioresistance of glioma stem cells
Authors: Madany Mecca , Edwards Lincoln , Yu John S.
Published: July 2017

The most prevalent brain cancer, Glioblastoma Multiforme (GBM) has an average survival of less than 2 years. Despite advances in therapy there is still an overall poor response to treatment which has been attributed to glioma stem cells (GSC’s), a subset of tumor cells that are able to self-renew, inhibit differentiation and are often chemo and radioresistant. The genetics and mechanisms underlying how glioma stem cells are able to repopulate tumors and affect patient survival desperately need to be defined. We are interested in delineating the role that ZEB1 (zinc finger e-box binding homeobox-1) loss has on GSC’s and what role this loss plays in the chemo and radioresistance of GSC’s. Most insights into ZEB1 regard it as tumorigenic and an initiator of EMT (epithelial mesenchymal transition). Surprisingly, in this study, we have shown that in TCGA datasets ZEB1 deletion frequently occurs and this loss actually results in poorer glioma patient survival. Copy number analysis as well as immunohistochemistry on patient samples shows that ZEB1 loss occurs both at the gene and protein level. Stable ZEB1 knockdown in our patient derived glioma stem cell lines results in increased proliferation and a resistance to differentiation. Following chemotherapy as well as radiotherapy, knockdown cell lines show increased cell viability as well as higher levels of secondary neurosphere formation. Decreased apoptosis and changes in cell cycle as well as the DNA damage response pathway were also observed in the knockdown lines following chemo and radiotherapy. Overall, this data indicates that loss of ZEB1 in GSC’s results in enhanced resistance to standard therapy. With these results, we have reason to believe that ZEB1 may be used as a novel therapeutic target to combat the chemo and radioresistance of glioma stem cells.

Citation Format: Mecca Madany, Lincoln Edwards, John S. Yu. Delineating the role of ZEB1 loss in the chemo and radioresistance of glioma stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3892. doi:10.1158/1538-7445.AM2017-3892
Abstract 3897: Novel inhibitor of GBM stem cells targets unique CREB & Myc-mediated self-renewal pathways regulated by CDK5
Authors: Mukherjee Subhas , Tucker-Burden Carol , Zhang Changming , Kong Jun , Chau Monica , Read Renee , Brat Daniel J.
Published: July 2017

Cancer stem cells exert enormous influence on neoplastic behavior, in part by governing asymmetric cell division and the balance between self-renewal & multipotent differentiation. Growth is favored by deregulated stem cell division, which enhances the self-renewing population & diminishes the differentiation program. To uncover mechanisms relevant to deregulated cell division in human glioma stem cells, we first developed a novel adult Drosophila brain tumor model, 100% enriched with tumor stem cells. Using this model, we performed a suppressor screen for kinases and found brain-specific dCdk5 partially reverses the tumor phenotype. dCdk5 and its human ortholog CDK5 (79% identity) are atypical protein kinases because they do not regulate cell cycle in normal cells, but are critical for neurogenesis & survival of mature neurons. Interestingly, many cancers show overactivation of CDK5 signaling, regulating cell cycle & leading to uncontrolled proliferation. Our analysis of TCGA data shows that IDH wt GBM has significantly high level of CDK5 compared to the IDH wt lower grade glioma. Additionally, we found a strong positive correlation between CDK5 & several stem cell markers in GBM. To date, not much is known about the role of CDK5 in glioblastoma GBM) & glioma stem cell self-renewal. Using patient-derived (GBM) neurosphere cultures & in vivo xenograft tumors in mice, we further demonstrated that a novel pharmaceutical suppressor of CDK5 signaling axis can suppress self-renewal properties through a new CDK5 phosphorylation site on CREB and Myc. Together, our results show that the CDK5 signaling pathway is important for glioma stem cell survival & that suppressing CDK5 could be a novel therapeutic approach to eliminate glioma stem cells.

Citation Format: Subhas Mukherjee, Carol Tucker-Burden, Changming Zhang, Jun Kong, Monica Chau, Renee Read, Daniel J. Brat. Novel inhibitor of GBM stem cells targets unique CREB & Myc-mediated self-renewal pathways regulated by CDK5 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3897. doi:10.1158/1538-7445.AM2017-3897
Abstract 3909: Investigating the role of ANXA2R in metastatic prostate cancer
Authors: Torga Gonzalo , Pienta Kenneth J.
Published: July 2017

Skeletal metastasis is the most life-threatening complication in prostate cancer. The molecular mechanisms behind the interactions between prostate cancer and the bone marrow premetastatic niche remain unknown. Understanding and preventing such interactions could lead to new promising therapeutic strategies against lethal prostate cancer. Annexin 2 receptor (ANXA2R) was originally identified as a cell surface receptor for Annexin 2 (ANXA2) that mediates the stimulatory effects of ANXA2 during osteoclastic activation and osteoblast mineralization. Moreover, ANXA2R is able to induce apoptosis independent of its ligand, partially through activating caspases using non-conventional apoptotic pathways. Osteoblasts and marrow endothelial cells express ANXA2 which functions as a regulator of hematopoietic stem cell engraftment. Previous studies demonstrated blocking ANXA2 or its receptor prevents prostate cancer cells from establishing bone metastases in mouse models. It has been recently proven that ANXA2R does not bind to ANXA2 directly but to S100A10 present in the complex annexin A2 heterotetramer (AIIt), composed of 2 ANXA2 bound to a S100A10 dimer. Higher levels of ANXA2 and S100A10 are associated with proliferating and invasive cancers and correlate with poor prognosis. However, the loss of ANXA2 expression appears to be specific for prostate cancer. Previous work on prostate cancer has focused solely on ANXA2 as a ligand. In this study, we demonstrate that S100A10 and ANXA2 are co-localized in prostate cancer, and their expression and ANXA2R levels vary with grade in primary tumors as well as within the different metastatic sites. Given prostate cancer cells as well as bone marrow stroma can simultaneously express the ligand and receptor and levels of AIIt decrease with tumor stage in the primary site, we hypothesize prostate cancer cells require S100A10 and not only ANXA2 to spread to bone and other tissues. ANXA2R could act as a dependence receptor, mediating withdrawal-induced programed cell death in prostate cancer cells in the absence of AIIt. Furthermore, AIIt-ANXA2R interactions between prostate cancer cells and the premetastatic bone marrow niche might play an important role in the development of skeletal metastasis by inducing selective pressures on prostate cancer cells to metastasize to the bone marrow which is abundant of AIIt.

Citation Format: Gonzalo Torga, Kenneth J. Pienta. Investigating the role of ANXA2R in metastatic prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3909. doi:10.1158/1538-7445.AM2017-3909
Abstract 3912: Pancreatic cancer cell interaction with platelets impedes cell cycle progression and increases viability
Authors: Cannon Andrew C. , Kumar Sushil , Hall Bradley , Bhatia Rakesh , Singh Rakesh , Batra Surinder
Published: July 2017

Background: Metastasizing cancer cells rapidly associate with platelets in circulation, but the nature and functional consequences of this interaction have yet to be fully elucidated. Here we investigated the physical interaction of platelets with pancreatic cancer (PC) cells and the contribution of platelet-derived platelet factor 4 (PF4) mediated signaling in PC cells.

Methods: Immunohistochemistry (IHC) and western blot analysis were performed to characterize the expression of PF4 receptor, CXCR3, in 42 Whipple samples and 8 PC cell lines respectively. Physical interaction of human platelets with PC cell lines and its impact on PC cell proliferation in low attachment conditions was analyzed by flow cytometry. Cell viability was assayed by MTT analysis. Immunofluorescence analysis was performed to evaluate PF4 induced autophagy.

Results: IHC and western blot analysis in Whipple samples showed CXCR3 expression in 86 percent of the pancreatic tumors and on all the tested PC cell lines respectively. Flow cytometry demonstrated that 24 percent of Capan1 cells interacted with platelets. Interestingly, incubation of platelets with cell-cycle-synchronized Capan1 cells under low attachment conditions inhibited the proliferation of PC cells (~10 percent) at 24 but not 48 hours. This effect was abrogated by pharmacological inhibition of CXCR3 with AMG487. Concurrently, the viability of Capan1 cells grown in low attachment conditions and treated with platelets for 72 hours was greater than that of control and AMG487 with platelets treated groups as assessed by MTT assay. Mechanistic studies suggested that recombinant PF4 augments autophagosome formation as an early event and increases the expression of p21 as a late event. Of note, both LC3 punctation and p21 expression are abrogated by concomitant incubation with PF4 and AMG487.

Conclusion: Platelets appear to rapidly interact with cancer cells in suspension. Additionally, in a PF4-CXCR3 signaling dependent manner, platelets inhibit cell cycle progression and increase PC cell viability in low attachment conditions. Cumulatively, these data suggest that platelets aid in the metastatic dissemination of pancreatic cancer cells.

Citation Format: Andrew C. Cannon, Sushil Kumar, Bradley Hall, Rakesh Bhatia, Rakesh Singh, Surinder Batra. Pancreatic cancer cell interaction with platelets impedes cell cycle progression and increases viability [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3912. doi:10.1158/1538-7445.AM2017-3912
Abstract 3914: KLF4-dependent perivascular plasticity enhances pre-metastatic niche formation and metastasis
Authors: Murgai Meera , Ju Wei , Eason Matthew , Kline Jessica , Kaplan Rosandra N.
Published: July 2017

Metastasis causes most cancer deaths, and new therapies that are based on a deeper understanding of this process are required to improve patient survival. Metastatic tumor cell colonization and growth is facilitated by a pre-metastatic niche microenvironment composed of hematopoietic cells, stromal cells, and extracellular matrix that support tumor survival and growth. Perivascular cells, including vascular smooth muscle cells (vSMCs) and pericytes, are a key cell population involved in new vessel formation critical to primary tumor development. Given the well-described plasticity of perivascular cells, we sought to determine whether perivascular cells regulate tumor cell survival and proliferation at metastatic sites. Using perivascular cell-specific and pericyte-specific lineage tracing models, we demonstrated that perivascular cells lose traditional vSMC/pericyte marker expression in response to tumor-secreted factors, and exhibit increased proliferation, migration and extracellular matrix (ECM) synthesis. Expression of the pluripotency gene Klf4 is increased and is critical for this phenotypic transition to a less differentiated state characterized by increased proliferation and ECM production. Genetic inactivation of Klf4 specifically in perivascular cells decreases pre-metastatic perivascular cell proliferation and consequently integrin-fibronectin dependent tumor metastasis. Our data reveal a previously unidentified role for perivascular cells in pre-metastatic niche formation, and suggest that modulation of stromal cell plasticity may provide a novel strategy for limiting metastasis.

Citation Format: Meera Murgai, Wei Ju, Matthew Eason, Jessica Kline, Rosandra N. Kaplan. KLF4-dependent perivascular plasticity enhances pre-metastatic niche formation and metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3914. doi:10.1158/1538-7445.AM2017-3914
Abstract 3922: NR2F1 limits dissemination and stemness of early breast cancer cells
Authors: Sosa Maria Soledad
Published: July 2017

Tumor cells derived from MMTV-Neu mouse models or human ErBb2+ primary tumors are known to be able to complete all steps of the metastatic cascade. However, new evidence show that Neu+ early cancer cells derived from early stages of tumor progression (before detection of palpable tumors), can disseminate and, as disseminated cancer cells (early DCCs), enter a non-proliferative state for prolonged periods of time at secondary organs. We recently showed that early DCCs contributed to metastasis formation together with late-arriving DCCs (those coming from overt tumors). However, the mechanisms that would allow these early cancer cells, considered sessile and with few genetic alterations, to complete all steps of metastasis are unknown. Here we report that downregulation of the orphan nuclear receptor NR2F1 in Neu+ early cancer mammary epithelial cells (MECs) further activated a motile phenotype and this was coincident with previously described detection of circulating cancer cells (CCCs) and lung and bone marrow DCCs in MMTV-Neu mouse model. Knock down of basal NR2F1 levels in Neu+ early cancer cells induced cell motility, loss of laminin-V deposition, β-catenin delocalization from the membrane, dramatic loss of E-cadherin junctions and increased percentage of leader cells positive for CK14 and PRRX1 staining. Interestingly, TWIST and PRRX1 levels became upregulated upon NR2F1 depletion in 3D structures. These results suggest that NR2F1 expression maintains epithelial identity and suppresses epithelial-mesenchymal transition (EMT). Knock down of NR2F1 in Neu+ early cancer cells enhanced mammosphere formation efficiency and this was accompanied by upregulation of the pluripotency transcription factor NANOG and EMT master regulator TWIST. Interestingly, early dormant DCCs (negative for proliferation markers) showed re-expression of NR2F1 levels while micrometastases (cycling cells) had reduced levels of NR2F1. This result suggests that downregulation of NR2F1 in early DCCs may contribute to the dormancy escape of early DCCs and consequently metastatic relapse. Our findings provide for the first time evidence that NR2F1 functions as a suppressor of stemness and dissemination during early stages of tumor progression. We propose that therapies that restore expression of NR2F1 might limit early dissemination and the progression of early and late-arriving DCCs toward metastatic outgrowth.

Citation Format: Maria Soledad Sosa. NR2F1 limits dissemination and stemness of early breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3922. doi:10.1158/1538-7445.AM2017-3922
Abstract 3932: Dual role of p120ctn in cancer: epithelial vs mesenchymal
Authors: Fonseka Pamali , Mathivanan Suresh , Liem Michael , Atukorala Ishara
Published: July 2017

Neuroblastoma, a paediatric cancer, accounts for 15% of childhood cancer mortality. Even though neuroblastoma is an aggressive cancer, the exact mechanisms by which the cells resist treatment is poorly understood. Here, we hypothesise that neuroblastoma cells have high expression of mesenchymal markers and hence could attribute to the aggressive phenotype. P120ctn is downregulated in epithelial cancers and is known to play a major role in EMT and aggressiveness. In this study, immunohistochemical staining of neuroblastoma patient tissues suggested that p120ctn is highly abundant. Hence, the role of p120ctn and N-Myc in neuroblastoma aggressiveness was investigated by using RNA interference. Amplification of N-Myc oncogene occurs in 20% of neuroblastoma patients and is considered high risk as it correlates with aggressiveness and poor prognosis. Interestingly, knockdown of p120ctn down regulated N-Myc both at mRNA and protein levels. Upon knockdown of p120ctn and N-Myc, the proliferation, invasion and migration of neuroblastoma cells were significantly reduced. Quantitative proteomic and qPCR analysis of the wild type and knockdown cells revealed that p120ctn knockdown cells underwent mesenchymal-to-epithelial transition. Confocal microscopy and Western blotting analysis of subcellular fractionation showed nuclear accumulation of β-catenin upon p120ctn knockdown. Once in the nucleus, β-catenin activated Wnt signalling pathway and up regulated Wnt target genes including C-Myc. Interestingly, down regulation of p120ctn sensitised the neuroblastoma cells to doxorubicin. Currently, there is no published study that explores the role of p120ctn in neuroblastoma. However, these findings are contradictory to scientific literature in the context of the functional role of p120ctn in epithelial cancer. Hence to validate our findings, we established knockdown of p120ctn in epithelial colorectal cancer cells. Consistent with the literature, knockdown of p120ctn induced EMT, proliferation and migration. These results suggest that the role of p120ctn is cell type dependent. Overall, the findings from this study suggest that p120ctn plays a pivotal role in progression of neuroblastoma.

Citation Format: Pamali Fonseka, Suresh Mathivanan, Michael Liem, Ishara Atukorala. Dual role of p120ctn in cancer: epithelial vs mesenchymal [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3932. doi:10.1158/1538-7445.AM2017-3932
Abstract 3965: Epithelial membrane protein-2 is a novel regulator of immune editing in breast cancer
Authors: Tsui Jessica , Ashki Negin , Chang Yuling , Patel Deven , Sjarif Jasmine , Wadehra Madhuri
Published: July 2017

Cancer immuno-editing is a process that describes the interaction between immune cells and tumor cells. This interaction can result in elimination of a developing tumor, tumor dormancy, or tumor cells that are capable of surviving in an immune-competent host. We have recently uncovered a novel mechanism of immunoediting by the tetraspan protein Epithelial membrane protein or EMP2. We propose that EMP2 serves as a bridge between innate and adaptive immunity via tumor mediated type I interferon expression. Most tumor cells evade the immune system through suppression or ignorance. EMP2 levels promote type I interferon expression which was found to correlate with PDL1 expression in a number of cell lines. Concordantly, in vivo, in multiple breast cancer cell lines, EMP2 promoted tumor growth. In contrast, reduction in EMP2 levels correlated with a reduction in tumor size and a corresponding increase in tumor associated macrophages. Given that tumors with lower levels of EMP2 grow poorly, we hypothesized that targeting EMP2 may provide a therapeutic benefit. Recently, we have developed a panel of novel IgG1 monoclonal antibodies to EMP2 and tested their ability to treat both xenograft and syngeneic mouse models. Our results show that anti-EMP2 IgG1 significantly reduces tumor load in both models in part through the recruitment of M1 macrophages. To explore this observation more fully, experiments using murine syngeneic models were employed. Anti-EMP2 therapy elicits a robust ADCC response, producing an immune infiltrate rich in macrophages, NK cells, and lymphocytes. In addition, we show that CD8 cells show reduced exhaustion in the presence of anti-EMP2 antibodies. Conclusions: EMP2 is a protein upregulated in a number of cancers in women including breast, ovarian, and endometrial tumors. Our work collectively show that EMP2 is a novel immune regulator where its expression creates an immunosuppressive tumor microenvironment. We thus predict that targeting EMP2 may improve therapeutic outcomes for cancers in women.

Citation Format: Jessica Tsui, Negin Ashki, Yuling Chang, Deven Patel, Jasmine Sjarif, Madhuri Wadehra. Epithelial membrane protein-2 is a novel regulator of immune editing in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3965. doi:10.1158/1538-7445.AM2017-3965
Abstract 3992: Immune regulation of disseminated tumor cell clearance versus metastatic growth
Authors: Korkaya Hasan , Lee Eunmi , Piranioglu Raziye , Ouzounova Maria , El-Andaloussi Abdeljabar , Asm Iskander , Korkaya Ahmet K. , Zhou Gang , Arbab Ali , Rodriguez Paulo
Published: July 2017

Metastatic disease is the end stage of extremely inefficient processes that entail overcoming multiple barriers including anti-tumor immunity. Although evidences from preclinical and clinical settings suggest that dissemination of malignant cells is an early process, majority of disseminated cells either eliminated or remain dormant in distant organs, while very few cells eventually develop successful metastasis. Therefore, it is widely accepted that dynamic and reversible tumor cell plasticity is required for metastasis, however, in vivo steps and molecular mechanisms are poorly elucidated.

We provide evidence that monocytic and granulocytic subsets of myeloid derived suppressor cells (m-MDS, g-MDSC) infiltrated in primary 4T1 tumor and distant organs with different time kinetics regulate spatiotemporal tumor plasticity. Using co-culture experiments and syngeneic mouse models of murine 4T1 (metastatic) tumor, we demonstrated that tumor infiltrated m-MDSCs facilitate tumor cell dissemination from the primary site by inducing the EMT/CSC phenotype. In contrast, g-MDSCs infiltrated in the lungs support metastatic growth by reverting the EMT/CSC phenotype and thus promoting tumor cell proliferation. In contrast, less invasive EMT6 tumors fail to induce efficient pulmonary infiltration of g-MDSCs and results in clearance of disseminated tumor cells in the lungs. Gene expression analyses of tumors and MDCS subsets in primary tumor site and distant organs at different time points reveal mechanistic temporal regulation of in vivo tumor plasticity by m-MDSC and g-MDSC subsets in 4T1 tumor-bearing mice. However, the lung microenvironment of EMT6 tumor-bearing mice display a gene expression signature of anti-tumor immunity which predict better survival in breast cancer patients. In our functional studies, we demonstrate that EMT6 tumor-bearing animals efficiently eliminate disseminated tumor cells in the lungs. Furthermore, g-MDSCs isolated from 4T1-tumor bearing animals significantly enhance metastatic growth of already disseminated tumor cells.

Consistent with the “seed and soil” hypothesis, our studies provide a molecular mechanism by which the immune system regulate spatiotemporal tumor plasticity and generation of permissive or anti-tumorigenic microenvironment in distant organs determining the fate of disseminated tumor cells.

Citation Format: Hasan Korkaya, Eunmi Lee, Raziye Piranioglu, Maria Ouzounova, Abdeljabar El-Andaloussi, Iskander Asm, Ahmet K. Korkaya, Gang Zhou, Ali Arbab, Paulo Rodriguez. Immune regulation of disseminated tumor cell clearance versus metastatic growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3992. doi:10.1158/1538-7445.AM2017-3992
Abstract 3998: Alerting the immune system by removing epigenetic silencing of Th1 chemokines
Authors: Sonnemann Heather M. , Giles Amber J. , Reid Caitlin M. , Hutchinson Marsha-Kay N. , Park Deric M. , Gilbert Mark R.
Published: July 2017

BACKGROUND: Solid tumors employ multiple mechanisms to evade an immune response. However, the potential to enhance the immune response to cancer has been proven in several malignancie and is under investigation in many others, including primary CNS tumors. Brain tumors in particular lack robust T-cell infiltration. Recent studies have found that certain tumors can be induced to express T-cell attracting chemokines, CXCL9 and CXCL10, by interferon gamma (IFNg). This response is further amplified using methyltransferase inhibitors (Peng, et al. Nature 2015. Vol 527: 249-253.), resulting in increased Tcell trafficking to tumors both in vitro and in vivo. We hypothesized that T-cell trafficking to brain tumors could likewise be enhanced with DNA and histone methyltransferase inhibitors to induce CXCL9 and CXCL10 transcription.

METHODS: Assays were performed on 7 human glioma brain tumor cell lines. CXCL9 and CXCL10 expression were measured by real-time PCR. Two commercially available methyltransferase inhibitors, 5-AZA-dC and GSK126, were utilized to demethylate DNA and histone H3 (K9 and K27), respectively. Histone methylation status was examined using Western blot. T-cell migration was measured using transwell migration assays.

RESULTS: IFNg increased CXCL9 and CXCL10 transcription in brain tumor lines. GSK126 and 5-AZA-dC enhanced expression of CXCL9 and CXCL10 compared to IFNg alone. Migration assays confirmed T-cell trafficking towards chemokines produced by tumor cells in response to methyltransferase inhibitors.

CONCLUSIONS: These studies demonstrate that brain tumors express T-cell attracting chemokines CXCL9 and CXCL10 in response to IFNg. Further, GSK126 and the combination of GSK126 and 5-AZA-dC enhanced expression of CXCL9 and CXCL10 transcription by real-time PCR and T-cell trafficking by migration assay. Together, these data provide a potential means to increase T-cell trafficking into tumors and potentially enhances the efficacy of immune therapies for brain tumors.

Citation Format: Heather M. Sonnemann, Amber J. Giles, Caitlin M. Reid, Marsha-Kay N. Hutchinson, Deric M. Park, Mark R. Gilbert. Alerting the immune system by removing epigenetic silencing of Th1 chemokines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3998. doi:10.1158/1538-7445.AM2017-3998
Abstract 400: NCI's CPTAC Phase III, proteogenomic analysis of additonal cancer types
Authors: Hannick Linda I.
Published: July 2017

The Clinical Proteomics Tumor Analysis Consortium (CPTAC) is a National Cancer Institute initiative that seeks to uncover the molecular basis of cancer using a proteogenomic approach to study prospective cancer specimens. Leidos Biomed provides an infrastructure for supporting the collection of high quality biospecimens and data, in addition to project and subcontract management for the program. CPTAC applies the understanding of the molecular basis of cancer to identify biomarker candidates. Phase II of CPTAC, completed in 2016, collected over 500 cases from breast, colon and ovarian patients. In early 2016, CPTAC Phase III began to collect and analyze 200 cases of each of ten additional cancers. The goal is to collect 200 qualified cases of five to six tumor types over a five-year period, although the program is currently accruing from ten. The study entails collection and pathology evaluation of biospecimens, high-quality clinical data and images from clinical sites around the world. A biorepository evaluates and processes the biospecimens, sending nucleic acids to a sequencing center and tissues to proteomics groups. Data are combined and analyzed by translational centers. Genomic data are made available to the research community through the NCI Genomic Data Commons. Proteomic data are made available through the Data Coordinating Center. We report here on progress in collection of tissues and clinical data, and use of biorepository, proteomics and genomics and analysis centers.

Citation Format: Linda I. Hannick. NCI's CPTAC Phase III, proteogenomic analysis of additonal cancer types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 400. doi:10.1158/1538-7445.AM2017-400