bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1094: A role for olfactory-like chemosensory signaling in prostate cancer metastasis
Authors: Lam Hong , Zhu Wanqu , Wang Hailun , Luo Jun , Zheng Qizhi , Valkenburg Ken , Hurley Paula , Pluznick Jennifer L. , Tran Phuoc T. , Marzo Angelo M. De , Isaacs William B. , Pienta Kenneth J. , An Steven S.
Published: August 2018

Odorant sensing G protein-coupled receptors (ORs) are the largest signaling family encoded by the mammalian genome. Historical understanding suggests these specialized receptors are only expressed on sensory neurons in the main olfactory epithelium and respond to external ligands involved in smell perception. More recently, olfactory-like chemosensory signaling has been found in a variety of non-sensory tissues and shown to be evoked by endogenous metabolic byproducts of anaerobic bacteria and hypoxia. Here we screened the full complement of ORs in the prostate and studied their expression and function in the context of metastatic-invasion of prostate cancer (PCa). In the germline of men with lethal PCa, we detected a large number of nonsynonymous coding changes in ~400 different OR genes including specific missense and loss-of-function mutations that are present in higher rates than would be predicted. RNA-Seq of clinical prostate samples showed higher OR51E2 expression in localized PCa than normal prostate. Most striking, we detected a low abundance of the OR51E2 transcript in PCa metastases to the bone relative to localized. Similarly, we found a marked reduction of OR51E2 expression in PCa cell lines that were derived from bone metastases, or those that had undergone an epithelial-mesenchymal transition (EMT) phenotype through co-culture with IL4-treated CD14+ monocytes. Using mouse models of PCa metastasis, we confirmed the overexpression of OR51E2 in localized tumors generated by subcutaneous injection while observing a marked reduction in PCa cells metastatic to the bone that also demonstrated a mesenchymal cellular phenotype. Together these findings establish, for the first time, a novel role for ‘sensory GPCRs' in PCa progression to metastasis.

Grant supports: The Johns Hopkins Discovery Award; The Johns Hopkins Catalyst Award; Maryland Cigarette Restitution Fund

Citation Format: Hong Lam, Wanqu Zhu, Hailun Wang, Jun Luo, Qizhi Zheng, Ken Valkenburg, Paula Hurley, Jennifer L. Pluznick, Phuoc T. Tran, Angelo M. De Marzo, William B. Isaacs, Kenneth J. Pienta, Steven S. An. A role for olfactory-like chemosensory signaling in prostate cancer metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1094.
Abstract 1095: Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) regulates mitochondrial dynamics, EMT and angiogenesis in progression of prostate cancer
Authors: Dheeraj Arpit , Tailor Dhanir , Deep Gagan , Singh Rana P.
Published: August 2018

Prostate cancer (PCa) is a major epithelial cancer among men and with the second highest incidence rate, worldwide. The high ratio of IGF-1/IGFBP-3 correlates with increased risk of many cancers including prostate cancer. In present study, we have evaluated the role of IGFBP-3 and effect of fisetin, a phytochemical, active constituent of strawberry, apple etc. in the progression of prostate cancer. The exogenous expression of IGFBP-3 moderately decreased the cell growth and it further decreased with addition of fisetin in DU145 and LNCaP cells. The restoration of IGFBP-3 in DU145 cells inhibited the clonogenic potential which is further decreased with fisetin treatment. Increased ROS content was observed in IGFBP-3 overexpression condition, however fisetin treatment reversed the ROS content in DU145, shows antioxidant behaviour. Morphological examination of mitochondria revealed that IGFBP-3 overexpression destabilizes the mitochondrial dynamics by reduction in active DRP1 level which has been reversed by fisetin treatment. We evaluated the effect on mitochondrial mass which was decreased in IGFBP-3 overexpressing DU145 cells which further decreased with addition of fisetin at 12 and 24 h. IGFBP-3 overexpression decreased the migratory potential of DU145 cells under normoxic conditions and under hypoxic condition it increased the migration of DU145 cells. Furthermore, IGFBP-3 overexpression decreased the VEGF expression as compared to vector control which can inhibit the expansion of tumor cells. Under the hypoxic conditions (1% oxygen), cells showed increased levels of IGFBP-3 when compared to normoxic conditions (21% Oxygen) in time dependent manner. The down-regulation of IGFBP-3 in PC3 cells, increased the expression of E-cadherin, a biomarker of epithelial to mesenchymal transition. The wound scratch assay showed the pro-migratory role of IGFBP-3 in PC3 cells and treatment with fisetin inhibited the migration of these cells under the hypoxic condition. The knockdown of IGFBP3 resulted in the decreased invasive potential of PC3 in comparison to cells in hypoxic state. Together with these observation, IGFBP-3 have shown biphasic character depending on normoxic and hypoxic condition in controlling the prostate cancer progression.

Citation Format: Arpit Dheeraj, Dhanir Tailor, Gagan Deep, Rana P. Singh. Insulin-like Growth Factor Binding Protein-3 (IGFBP-3) regulates mitochondrial dynamics, EMT and angiogenesis in progression of prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1095.
Abstract 1098: Innate immune response to primary breast cancer prevents metastasis-initiating cell colonization
Authors: Castano Zafira
Published: August 2018

Current lack of insight into mechanisms governing breast cancer metastasis has precluded development of curative therapies. Previous reports, including our own, have demonstrated that metastatic success is due to tumor cell intrinsic properties as well as microenvironmental and systemic factors (Castano, et al., Cancer Discovery, 2013). The goal of our current study was to determine whether metastasis initiating cells (MIC), i.e., cells enriched for metastatic capacity, also rely on systemic cues. Using a preclinical model of the early phases of breast cancer metastasis, when cells are disseminated in the presence of the primary tumor (McAllister, et al., Cell 2008), we were surprised to find that certain primary tumors inhibit progression of disseminated MICs into overt tumors. In the presence of the primary tumor, MICs were maintained in a Zeb1hi/CDH1lo state and were less proliferative and poorly differentiated relative to those that formed in the absence of the primary tumor. We established that the primary tumor induces mobilization of IL1beta-expressing innate immune cells that are recruited to sites where MICs reside. At those sites, signaling via the IL1 receptor maintains MICs in the Zeb1hi/CDH1lo state, thus promoting disease indolence. Confirming our xenograft results, we established that expression of IL1beta in patient tumors is associated with metastasis free survival. Collectively, these data highlight the profound impact a primary tumor can exert on metastasizing cells - in this case, by altering the systemic environment to the detriment of secondary tumor growth-. Moreover, our data highlight a central role for IL1 pathway in modulating tumor cell plasticity and suggest it may provide a novel avenue for targeting recurrent disease.

Citation Format: Zafira Castano. Innate immune response to primary breast cancer prevents metastasis-initiating cell colonization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1098.
Abstract 1109: S100A10 contributes to cancer stemness, invasion and metastasis of head and neck cancer cells
Authors: Tanaka Nobuyukit , Nishikawaji Taketo , Ogama Naoko
Published: August 2018

Head and neck cancer is one of the most common cancers worldwide, and an innovating therapy is awaited. We attempted to identify proteins associated with cancer stem cell phenotypes, and found an EF-hand protein S100A10 is highly expressed in the stem cell population. Together with its binding partner, Annexin-A2, S100A10 regulates a spectrum of dynamic membrane-related events, such as actin cytoskeleton control, vesicle formation and intercellular interaction. Immunohistochemical analysis using clinical head and neck cancer specimens showed that elevated S100A10 expression is typically present in the invasion front of tumors, and S100A10-high cases were associated with poor prognosis. S100A10 knockdown and knockout resulted in significant reduction of cell migration and invasion in vitro. Cell movement was slowed down by S100A10 knockdown. Accordingly, in vivo tumor formation was impaired by S100A10 depletion. Cell cycle progression was delayed by the depletion, suggesting its potential role in proliferation controls. These results suggest that S100A10 has a significant role in head and neck cancer cell proliferation and invasion.

Citation Format: Nobuyukit Tanaka, Taketo Nishikawaji, Naoko Ogama. S100A10 contributes to cancer stemness, invasion and metastasis of head and neck cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1109.
Abstract 1117: Norrin signaling is protumorigenic in glioblastoma progression
Authors: Elsehemy Ahmed A. , Selvadurai Hayden , Rowland Katherine , Dirks Peter , Wallace Valerie
Published: August 2018

Norrin signaling is protumorigenic in GBM progression

A-Introduction:

Norrin, a secreted factor encoded by the Norrie Disease Protein gene (NDP), is an atypical WNT ligand that specifically binds the FZD4 receptor and activates the canonical WNT signaling pathway in endothelial cells to regulate vascular development and barrier function in the brain. Recently, our group identified a novel tumor inhibitory function of NDP/FZD4 signaling in the endothelium in mouse models of medulloblastoma. Here we investigated the function of the NDP/FZD4 signaling axis in glioblastoma (GBM) progression.

B-Experimental approaches

GBM patients' survival data was obtained from TCGA and analyzed using the cBioportal server. Low passage mitogen expanded GBM cancer stem cell lines were established from primary tumors using standard conditions. NDP expression in experimental cell lines was modulated using lentiviral delivery of short hairpins or full length cDNA. Cell number was assessed by trypan blue cell counting, and sphere forming cell frequency was tested using extreme limited dilution assay (ELDA). For in vivo assessment of tumorigenesis, experimental and control cell lines were xenografted intracranially in NOD/SCID/Gamma (NSG) mice and symptomatic animals were euthanized and brains collected for histological analysis.

C-Results

Analysis of GBM data from TCGA showed that survival and NDP expression are negatively GBM. Gene expression analysis indicated variable expression levels of NDP/FZD4 signaling pathway components in a panel of 10 primary GBM stem cell lines. In vitro gain and loss of function studies showed that NDP promotes proliferation and sphere formation in GBM. Moreover, the effects of are recapitulated in xenografts. NDP appears to control GBM differentiation, as it affects the proportion of cycling (Ki67+) cells and the level of stemness (Sox2 levels). Finally, NDP function is independent of FZD4 and canonical Wnt signaling, indicating that it functions through an alternative pathway.

D-Conclusions Our in vitro and in vivo results indicate that Norrin might have an oncogeneic role in GBM. In addition, the effect of Norrin is FZD4- and WNT-independent. Our results indicate that targeting Norrin GBM might be a potential therapeutic approach.

Citation Format: Ahmed A. Elsehemy, Hayden Selvadurai, Katherine Rowland, Peter Dirks, Valerie Wallace. Norrin signaling is protumorigenic in glioblastoma progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1117.
Abstract 1122: MST4 phosphorylation of ATG4B regulates autophagic activity, tumorigenicity, and radio resistance in glioblastoma
Authors: Huang Tianzhi , Kim Chung Kwon , Alvarez Angel A. , Pangeni Rajendra P , Wan Xuechao , song xiao , shi Taiping , Yongyong Yongyong , Sastry Namratha , Horbinski Craig , Lu Songjian , Stupp Roger , Kessler John , Nishikawa Ryo , Nakano Ichiro , Sulman Erik , Lu Xinghua , James Charles David , Yin Xiao-Ming , Hu Bo , Cheng Shi-Yuan
Published: August 2018

Autophagy-mediated intracellular catabolism sustains the rapid growth of established tumors and tumors in response to multiple stresses including genotoxic/cytotoxic therapies. Here we identify and validate ATG4B, a key regulator that stimulates autophagic process by promoting autophagosome through reversible modification of ATG8 as a novel substrate of mammalian sterile20-like kinase (STK) 26/MST4 that is less known for its function in cellular process (none in autophagy) and unknown authentic substrates in cancer. We show that MST4 phosphorylates ATG4B at serine residue 383, which stimulates ATG4B activity and increases autophagic flux. Inhibition of MST4 or ATG4B activities suppresses autophagic process and the tumorigenicity of glioblastoma (GBM) cells. Furthermore, radiation induces MST4 expression, ATG4B phosphorylation and autophagy. Inhibiting ATG4B in combination with radiotherapy in treating mice with intracranial GBM tumor xenografts markedly slows tumor growth and provides significant survival benefit to animal subjects. This study not only describes a novel regulatory mechanism by which the MST4-ATG4B axis accelerates autophagic process, regulates GBM tumorigenicity, and responses to radiotherapy (RT), but also explores imminent clinical utility of combination of ATG4B inhibition with RT to suppress orthotopic GBM tumor xenografts. This study should prove generalizable to other types of cancer and have positive impacts in advancing our knowledge of cancer biology and designing new cancer treatments.

Citation Format: Tianzhi Huang, Chung Kwon Kim, Angel A. Alvarez, Rajendra P Pangeni, Xuechao Wan, xiao song, Taiping shi, Yongyong Yongyong, Namratha Sastry, Craig Horbinski, Songjian Lu, Roger Stupp, John Kessler, Ryo Nishikawa, Ichiro Nakano, Erik Sulman, Xinghua Lu, Charles David James, Xiao-Ming Yin, Bo Hu, Shi-Yuan Cheng. MST4 phosphorylation of ATG4B regulates autophagic activity, tumorigenicity, and radio resistance in glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1122.
Abstract 1126: Exploring the roles of Suppressor of Fused in the postnatal neurogenic niche and tumorigenesis
Authors: Castillo Jesse Garcia , Gomez Hector G. , Aguilar David , Pleasure Samuel J. , Yabut Odessa
Published: August 2018

Isolated brain tumors consist of cells with stem cell features and a tissue microenvironment similar to the neurogenic niche, implying that tumors must require the same niche factors for tumor growth and progression. Thus, a better understanding of how neural stem cell (NSC) behavior is regulated can have significant therapeutic implications in brain cancers. To this end, we examined the roles of Suppressor of Fused (Sufu) in the postnatal neurogenic niche of the forebrain, the ventricular-subventricular zone (V-SVZ), a potential site of origin for forebrain tumors. Given that recent studies showed low expression of Sufu in gliomas, we wondered how conditional deletion of Sufu using the hGFAP-Cre driver (hGFAP-cre/+;Sufu-fl/fl) influences NSC behavior in the V-SVZ. We found that Sufu critically controls NSC proliferation, since loss of Sufu in the hGFAP-cre/+;Sufu-fl/fl mice resulted in abnormal expansion of the V-SVZ. These defects were due to the increased production of DCX+ Type A cells at the expense of transit amplifying Type C and oligodendrocyte precursor cells. Furthermore, many of these cells failed to migrate out of the V-SVZ, where they remained and continued to proliferate. Nevertheless, an increase in apoptotic cells was observed, which likely prevented the formation of brain tumors from loss of Sufu function alone. Indeed, our preliminary studies showed that the combined deletion of Sufu and the tumor suppressor p53 (hGFAP-Cre/+;Sufu-fl/fl;p53-fl/fl) resulted in a more severe and sustained cell expansion phenotype in the V-SVZ. We predict that these genetic conditions predispose NSCs within the V-SVZ to form tumors at later postnatal stages. We are now investigating this and the molecular mechanisms by which Sufu exerted this effect. Of particular focus is the role of Sufu as an inhibitor of the mitogenic Sonic hedgehog (Shh) signaling, which is highly active in various glioblastoma subtypes. Taken together, our findings point to a potential role for Sufu in preventing tumor development in the forebrain. Our studies also provide novel insights on how developmental and oncogenic signals converge to initiate tumorigenesis or tumor progression. We hope that these studies will lead to the identification of critical niche factors that may be targeted to treat brain cancers and improve patient outcome.

Citation Format: Jesse Garcia Castillo, Hector G. Gomez, David Aguilar, Samuel J. Pleasure, Odessa Yabut. Exploring the roles of Suppressor of Fused in the postnatal neurogenic niche and tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1126.
Abstract 1138: LBH, a novel WNT effector in promoting basal-like breast cancer
Authors: Ashad-Bishop Kilan C. , Briegel Karoline J.
Published: August 2018

BACKGROUND: Clinically aggressive basal-like breast cancers (BLBC) disproportionally contribute to cancer deaths, but lack effective treatment options due to absence of expression of key therapeutic targets (ER, PR, HER2). New evidence suggests BLBC may originate from luminal breast epithelial cells through luminal-to-basal cell lineage conversion and dedifferentiation. However, the factors that reprogram cell fate and differentiation states during BLBC development remain poorly understood.

Our laboratory has identified a novel WNT/β-Catenin target transcriptional regulator, Limb-Bud-and-Heart (LBH), which is majorly overexpressed in aggressive BLBC harboring WNT hyperactivation. We previously showed in a conditional LBH knockout mouse model in vivo that LBH is a key stem cell and basal lineage regulator in normal mammary gland development. However, it's role in breast cancer remains elusive. Here, we crossed conditional LBH knockout (KO) mice with a mouse model for WNT-driven breast cancer (MMTV-Wnt1) to test if LBH is a critical effector of WNT-driven basaloid breast cancer, and whether its inhibition may affect BLBC tumorigenesis.

RESULTS: In our in vivo mouse model, epithelial-specific LBH inactivation using a Keratin 14/K14-Cre significantly attenuated Wnt1-induced mammary gland hyperplasia and delayed tumor onset. Yet, tumor volumes and burden were not changed, indicating that LBH is not essential for WNT-induced tumorigenesis. However, LBH-deficient MMTV-Wnt1-transgenic tumors exhibited pronounced histopathological differences compared to LBH WT MMTV-Wnt1-transgenic tumors. Whereas Wnt1+;K14CreLbh WT tumors were highly vascularized, disorganized, with mixed basal and luminal cell identity; tumors from Wnt1+;K14CreLbh KO mice were more organized, differentiated, and predominantly luminal Keratin 8 positive. We are currently investigating if the attenuated hyperplasia and tumor onset caused by LBH loss may be due to a deficiency in cancer stem cells in this breast cancer model.

CONCLUSION: Our data indicate that LBH is an essential cell fate regulator downstream of WNT signaling that maintains basal lineage identity and the undifferentiated nature of BLBC. Thus, LBH inhibition may be a novel strategy to reduce the high mortality of BLBC patients through differentiation therapy.

Citation Format: Kilan C. Ashad-Bishop, Karoline J. Briegel. LBH, a novel WNT effector in promoting basal-like breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1138.
Abstract 1139: An shRNA screening reveals that the tumorigenic effect of FBXO11 is inversely correlated with EMT profiles in breast cancer
Authors: Kim Jiyoung , Bagger Sofie O. , Hopkinson Branden B. , Villadsen René , Petersen Ole W.
Published: August 2018

Over the last decade a trend to study cancer stem cells (CSCs) has become synonymous to studying epithelial to mesenchymal transition (EMT), and has emerged in the field of breast cancer research. In turn, tumorigenesis of epithelial luminal-like breast cancer has been largely overlooked. Recently however, we and others have provided evidence that tumorigenic capacity is not always restricted to EMT-like cancer cells. Furthermore, the metastatic feature is conveyed by subclones of phenotypically differentiated non-EMT cancer cells. In this study, we aimed to identify the differential tumorigenic mechanisms of more aggressive non-EMT cells against the less aggressive EMT cells in breast cancer. By using loss of function screening, we found that a member of the E3 ubiquitin ligase complexes, FBXO11, facilitates tumor formation of non-EMT like cells by inhibiting the p53/p21 pathway. More importantly, our data showed that roles of FBXO11 in tumorigenesis are highly cell-type dependent. In conclusion, our study empathizes that it is important to understand the complexities of individual tumors in the development of personalized therapy.

Citation Format: Jiyoung Kim, Sofie O. Bagger, Branden B. Hopkinson, René Villadsen, Ole W. Petersen. An shRNA screening reveals that the tumorigenic effect of FBXO11 is inversely correlated with EMT profiles in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1139.
Abstract 114: Basal-like breast cancer engages tumor-supportive macrophages via cytokines triggered by extracellular S100A4
Authors: Prasmickaite Lina , Tenstad Ellen M. , Egeland Eivind Valen , Pettersen Solveig , Jabeen Shakila , Nord Silje , Haugen Mads Haugland , Juell Siri , Øyjord Tove , Engebråten Olav , Mælandsmo Gunhild Mari
Published: August 2018

Recently the biological and therapeutic perspective on cancer has evolved from focusing on tumor cells only, to include the complex impact of the tumor microenvironment (TME). The TME appears to have a strong influence on both tumor progression and response to treatment. In breast cancer, and in particular the triple-negative subgroup, patient outcome together with the therapeutic response are strongly linked to the tumor's inflammatory profile: presence of tumor-infiltrating leukocytes and their regulatory cytokine. Tumor-associated macrophages (TAMs) are among the most abundant immune cells in the TME, and expression of such cells has been strongly correlated with both poor outcome and development of resistance.

In this study we explored the effect of the pro-metastatic, inflammation-associated, TME factor S100A4 on breast cancer cells (BCCs) of different subtypes, and their further interactions with inflammatory cells. We show that S100A4 activates BCCs, stimulating secretion of pro-inflammatory cytokines, which, in turn, promotes monocyte conversion into TAM-like cells. This was in particular prominent for cytokines secreted from basal-like BCCs. The TAM-like cells possess pro-tumorigenic activities, including increased resistance and ability to migrate. In conclusion, we demonstrate that S100A4 instigate an inflammatory microenvironment, involving a network of cytokines and TAMs, which is particularly pronounced in basal-like BC and could facilitate aggressive phenotypes of this subtype.

Citation Format: Lina Prasmickaite, Ellen M. Tenstad, Eivind Valen Egeland, Solveig Pettersen, Shakila Jabeen, Silje Nord, Mads Haugland Haugen, Siri Juell, Tove Øyjord, Olav Engebråten, Gunhild Mari Mælandsmo. Basal-like breast cancer engages tumor-supportive macrophages via cytokines triggered by extracellular S100A4 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 114.
Abstract 1143: Prox1 and Notch mark distinct colorectal cancer stem cell populations
Authors: Högström Jenny , Heino Sarika , Kallio Pauliina , Lähde Marianne , Leppänen Veli-Matti , Kaijalainen Seppo , Balboa Diego , Otonkoski Timo , Robine Sylvie , Wiener Zoltan , Alitalo Kari
Published: August 2018

Colorectal cancer (CRC) is one of the leading causes of cancer-related morbidity and mortality. Signaling pathways, such as the Wnt and Notch pathways, are essential for the maintenance and differentiation of wild-type intestinal stem cells. We have shown that the Prox1 transcription promotes expansion of the colorectal cancer stem cell pool and that a subpopulation of the Prox1+ CRC cells display stem cell activity. Because of these results we have further analyzed the role of Prox1 in the regulation of CRC stem cell. Here, we report that Prox1 regulates CRC stem-like cells via bidirectional interaction with Notch1 during CRC initiation and progression. Using genetic in vivo models and ex vivo 3D organoid cultures, we show that Notch inhibition decreases the number of Lgr5+ stem cells whereas it increases expression of the Prox1. Although Notch inhibition led to increased proliferation of the Prox1 positive cells, it did not affect their ability to give rise to differentiated Prox1 negative progeny. Ectopic overexpression of the active fragment of Notch1 suppressed Prox1 expression and inhibited stem cell activity in the CRC cells. On the other hand, the PROX1-NuRD complex suppressed the Notch signaling pathway and Prox1 deletion increased Notch target gene expression and promoter activity, indicating reciprocal regulation between Prox1 and Notch1. Thus, although Prox1 and Notch suppress each other in colorectal cancer cells, Prox1+ cells can function as a stem cell population without the need for Notch pathway activity.

Citation Format: Jenny Högström, Sarika Heino, Pauliina Kallio, Marianne Lähde, Veli-Matti Leppänen, Seppo Kaijalainen, Diego Balboa, Timo Otonkoski, Sylvie Robine, Zoltan Wiener, Kari Alitalo. Prox1 and Notch mark distinct colorectal cancer stem cell populations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1143.
Abstract 1144: Building Kras (G12D)/Trp53 null/Pdx1-cre (KPC) mouse allograft tumor model for efficacy evaluation of combinatory immunotherapies
Authors: Song Yanrui , Liu Benqi , An Annie Xiaoyu , Zhang Likun , Cai Jie , Shi Qian , Li Henry Qixiang , Ouyang Davy Xuesong
Published: August 2018

Pancreas ductal adenocarcinoma (PDAC) has dreadful 5-year survival of 6% and remains one of the most difficult to treat cancers with very few standard-of-care options. Fueled by the clinical success of immune checkpoint inhibitors in other solid tumors, several clinical trials have been conducted in PDAC patients. Unfortunately, those attempts have achieved limited clinical benefits as single-agent treatment. Now investigators are eager to test combinatory therapies of chemotherapies, small-molecule immune modulators, and immune checkpoint antibodies. Highly relevant preclinical models are very much needed for proof-of-principle efficacy evaluation. KPC model, first described by Tuveson and colleagues as LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre, and later established in a variety of derivatives by several labs with Trp53 heterozygous or homozygous knockouts, recapitulates human PDAC tumors in many aspects including morphologic small ductal tumors with enriched stromal contents; key features of immune microenvironment of PDAC representing robust inflammatory reactions, like high levels of B cells and macrophages and exclusion of effector T cells; and most importantly, is nonresponsive to a series of chemotherapies and immune checkpoint inhibitors, including PD1 and CTLA4 antibodies. These features make KPC model an ideal model to test combinatory therapies for PDAC. However, parental KPC model is difficult to use for pharmacologic studies due to the spontaneous nature of tumor onset and progression. The compound mutant mice are also costly to breed. We have generated a transplantable KPC tumor model by passaging the primary tumor subcutaneously in the C57BL/6 mice. These KPC allografts retain morphologic similarity to human PDAC. Immune profiling of both subcutaneously and orthotopically grafted tumors demonstrated highly enriched CD45+ lymphocytes, particularly B cells and macrophages, in the tumor. The tumor is also nonresponsive to gemcitabine treatment, in line with the data from parental line. Orthotopically engrafted tumor leads to lethality of the host with the median survival time of 25 days. We are now testing a variety of combinatory therapies with chemotherapies, immune modulators and immune checkpoint antibodies. The results will be presented at the meeting.

Citation Format: Yanrui Song, Benqi Liu, Annie Xiaoyu An, Likun Zhang, Jie Cai, Qian Shi, Henry Qixiang Li, Davy Xuesong Ouyang. Building Kras (G12D)/Trp53 null/Pdx1-cre (KPC) mouse allograft tumor model for efficacy evaluation of combinatory immunotherapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1144.
Abstract 115: Crosstalk between breast cancer cells and macrophages in tumor microenvironment induces inflammasome activation
Authors: Jang Jeong-Hoon , Kim Do-Hee , Park Sin-Aye , Kim Su-Jung , Surh Young-Joon
Published: August 2018

The inflammasome is a multiprotein complex that is composed of NOD-like receptor, ASC and caspase-1. During the activation of the inflammasome, pro-interleukin (IL)-1β is cleaved by active caspase-1 to produce mature IL-1β. Although the inflammasome plays a controversial role in many types of tumor, emerging evidence indicates that the inflammasome functions as a negative regulator of breast cancer progression. Notably, high levels of IL-1β in breast cancer tissues are associated with a more virulent tumor phenotype and poor prognosis. However, it remains unresolved how IL-1β is accumulated in breast tumor microenvironment. In the present study, we have found that various human breast cancer cells (MDA-MB-231, MDA-MB-468, SKBr3, MCF-7 and T47D) retain cleaved-IL-1β whereas secretion of IL-1β into the culture medium was not observed. However, IL-1β was detected in the medium when human breast cancer cells were co-cultured with human monocytic (THP-1) cells. Among the various human breast cancer cells, triple-negative breast cancer cells (MDA-MB-231 and MDA-MB-468) effectively stimulated secretion of IL-1β. When co-cultured with MDA-MB-231 cells, THP-1 cells exhibited the elevated levels of pro- and cleaved-IL-1β. Consistent with this result, there was a marked increase in the secretion of IL-1β from THP-1 cells treated with the conditioned media of triple-negative breast cancer cells. Both triple-negative MDA-MB-231 and MDA-MB-468 breast cancer cells induced ASC oligomerization, which is a hallmark of inflammasome activation. Thus, it is likely that soluble factors from breast cancer cells promote IL-1β secretion from macrophages through activation of inflammasomes. In conclusion, breast cancer cells drive inflammasome activation in macrophages, thereby stimulating the accumulation of IL-1β in the tumor microenvironment. The secreted-IL-1β, in turn, promotes breast cancer progression.

Citation Format: Jeong-Hoon Jang, Do-Hee Kim, Sin-Aye Park, Su-Jung Kim, Young-Joon Surh. Crosstalk between breast cancer cells and macrophages in tumor microenvironment induces inflammasome activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 115.
Abstract 1153: Development and validation of a novel in vitro model of the tumor immune microenvironment
Authors: ZHOU RUOLAN , Weathered Rachel , Alonzo Luis , Mezyk-Kopec Renata , Swartz Melody
Published: August 2018

Tumor-associated lymphatics and their connection to the tumor-draining lymph node (TDLN) play important roles in cancer metastasis as well as in modulating the immune microenvironment. They bathe the TDLN in cytokines, exosomes, antigens, and suppressive factors from the tumor microenvironment to alter the anti-tumor immune response. These interactions are difficult to study in vivo, yet currently, these interactions cannot be readily explored in vitro. Here, we developed a perfused paper-based cell culture platform which can recreate the 3-dimensional architecture, stromal component and physiological levels of interstitial flow of the native tissue environment, while keeping the device high-throughput, easy to use, and inexpensive. This platform can sustain the long-term cultures (>3 weeks) of a number of tumor cell lines, which form complex architectures reminiscent of actual tumors, as well as of excised tumor tissue. The platform also supports the function and viability of immune cells (such as T lymphocytes and dendritic cells) and stromal cells (such as lymphatic endothelial cells and fibroblasts). To model the tumor interaction with its TDLN, we created a model in which tumor cells and lymph node stromal cells (LNSC) are cultured in separate but connected compartments under perfusion. To validate this, we have demonstrated preferential tumor migration to preconditioned (vs. unconditioned) LN stroma. The LN stroma compartment also supports co-culture of dendritic cells and T lymphocytes. To validate the modeling of the crosstalk between the tumor and TDLN, we show that tumor conditionioning of the LN primes the LN microenvironment to dampen cytotoxic T cell function. Together, these data highlight the potential of this system for studying complex tumor-host cell interactions in the tumor microenvironment over long periods of time, and paves the way towards an in vitro screening platform for drug screening for drugs that target cells or factors in the tumor microenvironment that serve as barriers to both chemotherapy as well as immunotherapies.

Citation Format: RUOLAN ZHOU, Rachel Weathered, Luis Alonzo, Renata Mezyk-Kopec, Melody Swartz. Development and validation of a novel in vitro model of the tumor immune microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1153.
Abstract 116: IGFBP2 promotes tumor progression by inducing alternative polarization of macrophages in pancreatic ductal adenocarcinoma
Authors: Sun Longhao , Liu Liang , Tian Weijun , Zhang Zhixiang , Kang Ya'an , Wang Huamin , Fleming Jason B. , Pasche Boris C. , Zhang Wei
Published: August 2018

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal and aggressive malignancy. Tumor-associated macrophages (TAMs) mainly represent the M2-like phenotype, with potent immunosuppressive activity, and play a pro-tumor role in nearly all aspects of PDAC biology. Elevated infiltration of M2 TAMs is associated with poor prognosis in PDAC. Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogene that induces PDAC progression and is involved in the regulation of immune responses. Our recent study demonstrated that IGFBP2 potentiates signal transducer and activator of transcription 3 (STAT3) transactivation activities in glioma. Considering the essential role of IGFBP2 in governing tumor progression and immune evasion of PDAC, we hypothesized that IGFBP2 promotes tumor progression by inducing alternatively activated macrophages in PDAC. In this study, immunohistochemical (IHC) staining for human PDAC clinical samples was used to reveal the relationship among IGFBP2 expression, M2 TAM accumulation and patient survival. The function of IGFBP2 in inducing alternative polarization of macrophages and promoting tumor progression in PDAC through the STAT3 pathway were evaluated using in vitro and in vivo assays. Ingenuity pathway and gene set enrichment analyses were used to identify the correlation of IGFBP2 gene expression with all other genes in the genome and enriched pathways associated with IGFBP2 gene expression. Our results provide evidence that IGFBP2 expression is associated with M2 macrophage accumulation in the tumor microenvironment and with poor prognosis in PDAC. IGFBP2 augments the production and secretion of IL-10 through activation of STAT3 in PDAC cells, thus reprogramming the TAMs polarization toward an M2 phenotype and promoting tumor progression. These findings established IGFBP2 as an immune-suppressor in the PDAC microenvironment and suggested a strategy for targeting IGFBP2 to improve PDAC immunotherapy.

Citation Format: Longhao Sun, Liang Liu, Weijun Tian, Zhixiang Zhang, Ya'an Kang, Huamin Wang, Jason B. Fleming, Boris C. Pasche, Wei Zhang. IGFBP2 promotes tumor progression by inducing alternative polarization of macrophages in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 116.
Abstract 1161: Interaction between doxorubicin and amniotic membrane stem cells on the canine inflammatory mammary cancer cell line IPC-366
Authors: Borghesi Jessica , Caceres Sara , Mario Lara C. , Hayashi Rafael Gonçalves , Peña Laura , Alonso-Diez Angela , Illera Maria J. , Silvan Gema , Miglino Maria A. , Carreira Ana C. Oliveira , Favaron Phelipe Oliveira , Illera Juan C.
Published: August 2018

The aim of this study was to evaluate the efficiency of doxorubicin, canine amniotic membrane stem cells (AMC) and the association between them in the triple-negative canine inflammatory mammary cancer cell line IPC-366. Experiments were carried out for 72 hours in 4 groups: IPC-366 untreated cells; cells treated with 10mg/mL of doxorubicin; coculture IPC-366 cells with 105 AMC; and cells treated with doxorubicin+AMC. MTT assays were performed for evaluating proliferation; flow cytometry to analyze hormonal and angiogenesis markers, and anti-inflammatory cytokines; and EIA techniques were used to evaluate secretion of steroid hormones (progesterone (P4); dehydroepiandrosterone (DHEA); androtenedione (A4); 17β-estradiol (E2); estrone sulphate (SO4E1)) in cell culture media. Results showed that cells treated with 10 mg/mL of doxorubicin resulted in a reduction of 71.64% on cell proliferation at 72h of treatment. A reduction in the expression of VEGF and PCNA-3 was observed by flow cyotmetry in treated cells compared to control cells. Differences on IL-10 were found within groups: treatment with doxorubicin resulted in a reduction on IL-10 expression although in AMC group expression remained similar to control group. Estrogen intracellular levels were significantly increased in doxorubicin+AMC group (4.67% vs. 27.1%). Regarding steroid hormone secretion, in AMC treated group any differences in hormone levels were found compared to control group. P4 and E2 secretion resulted in an increase in doxorubicin-treated group although in doxorubicin+AMC group these levels decreased with respect to control group. DHEA secretion was significantly decreased in treated groups compared to control group. Interestingly, A4 and SO4E1 secretion levels showed a significant increase compared to control group. Collectively, these results suggest that combination of doxorubicin and AMC caused a synergy that alters the cancer cell's secretion hormone profile by accumulation of estrogens. These findings attempt to give an approach of the combination of well-known treatments and amniotic stem cells as a canine mammary tumors therapy.

Citation Format: Jessica Borghesi, Sara Caceres, Lara C. Mario, Rafael Gonçalves Hayashi, Laura Peña, Angela Alonso-Diez, Maria J. Illera, Gema Silvan, Maria A. Miglino, Ana C. Oliveira Carreira, Phelipe Oliveira Favaron, Juan C. Illera. Interaction between doxorubicin and amniotic membrane stem cells on the canine inflammatory mammary cancer cell line IPC-366 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1161.
Abstract 1163: Chemoprevention of testosterone-induced benign prostatic hyperplasia by hexane fraction from seeds of Annona muricata (soursop) in rats
Authors: Adaramoye Oluwatosin A. , Oladipo Taiwo D. , Akanni Olubukola O. , Owumi Solomon O. , Abiola Olusoji J.
Published: August 2018

Alternative medicine is an extensively recognized therapeutic approach for the management of several diseases. Annona muricata commonly called sour sop is traditionally used to manage an array of human diseases, especially cancer. In this study, we hypothesized that hexane fraction from seeds of Annona muricata (HFAM) will ameliorate testosterone propionate (TP)-induced benign prostatic hyperplasia (BPH) in rat model. Castration was performed via the scrotal route under ketamine anesthesia and BPH was induced through daily intraperitoneal injection of TP (3 mg/kg) for 4 weeks after castration. Rats were assigned into six groups of six animals each viz: non-castrated control, castrated control, castrated rats that received TP (BPH group), BPH + HFAM, BPH + HFAM + finasteride, BPH + finasteride. Results showed that BPH rats had 3.1 and 2.4 folds increase in prostatic and organo-somatic weight, respectively. Furthermore, BPH increased the activities of total acid and alkaline phosphatases by 62% and 53%, respectively, and levels of lipid peroxidation products by 48% in the prostate of rats. Also, BPH caused significant increase in the levels of inflammatory markers (Myeloperoxidase and total nitric oxide) in rats. In contrast, there were no significant differences in the activities of prostatic antioxidant enzymes in BPH group relative to others. In BPH group, immuno-histochemistry revealed strong expression of prostatic inducible nitric oxide synthase, Bcl2, beta-catenin, androgen and estrogen receptors proteins, while mild expression of p53 and Bax were observed. Interestingly, treatment of BPH rats with HFAM or HFAM + finasteride significantly attenuated inflammatory indices and induced apoptotic parameters. Overall, hexane fraction from seeds of Annona muricata may be used as a therapeutic agent for BPH via anti-inflammatory effect.

Citation Format: Oluwatosin A. Adaramoye, Taiwo D. Oladipo, Olubukola O. Akanni, Solomon O. Owumi, Olusoji J. Abiola. Chemoprevention of testosterone-induced benign prostatic hyperplasia by hexane fraction from seeds of Annona muricata (soursop) in rats [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1163.
Abstract 1166: Identification of predictive markers for clinical efficacy of triple-negative breast cancer chemotherapy
Authors: Yun Jihui , Hur Saem , Kang Wonyoung , Na Deukchae , Chae Jeesoo , Kang Jinjoo , Kim Ju-Hee , Lee Jiwoo , Heo Woohang , Han Wonshik , Lee Charles , Noh Dong-Young , Moon Hyeong-Gon , Kim Jong-Il
Published: August 2018

Triple Negative Breast Cancer (TNBC) is uncommon type of invasive breast cancer accounting for about 10~20% of all breast cancers. TNBC is characterized by a lack of expression of estrogen receptors (ER), human epidermal growth factor receptor 2 (HER2) and progesterone receptors (PR). Due to this characteristic, common treatments including hormone therapy and drugs targeting these receptors are not effective against TNBC despite more aggressive clinical behavior when compared to other subtypes. Paclitaxel is one of the well-known chemotherapeutic agents used in treatment for patients with breast cancer. However, previous studies have reported that advanced breast cancer treated with paclitaxel often develop resistance to the paclitaxel. To understand molecular characteristics and mechanism associated with molecular adaption in cancer cell when treated with paclitaxel, we performed next generation sequencing (NGS) and in vivo experiment using patient derived xenograft (PDX) models. We established ten PDX models from two cases with TNBC each. Mice were divided into two group consisting of control (n=5) and paclitaxel treatment (n=5). We performed exome and transcriptome sequencing on three of five samples for each group. We didn't find significant differences between control and paclitaxel treatment groups in exome data. In transcriptome data, We identified 14 differentially expressed genes (DEGs) including members of CXCL gene family between control and paclitaxel treatment groups. Among these DEGs, 13 DEGs were up-regulated in paclitaxel treatment groups when compared to control group. We are conducting in vitro experiment for several genes among these 13 DEGs. Furthermore, we will perform transcriptome sequencing on PDX tumor samples of additional cases with TNBC for validation of the results so far achieved.

Citation Format: Jihui Yun, Saem Hur, Wonyoung Kang, Deukchae Na, Jeesoo Chae, Jinjoo Kang, Ju-Hee Kim, Jiwoo Lee, Woohang Heo, Wonshik Han, Charles Lee, Dong-Young Noh, Hyeong-Gon Moon, Jong-Il Kim. Identification of predictive markers for clinical efficacy of triple-negative breast cancer chemotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1166.