bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5239: Preventive effects of pentoxifylline on hepatic tumorigenesis in a novel mouse model of NASH-related liver cancer
Authors: Shirakami Yohei , Maruta Akinori , Obara Koki , Ideta Takayasu , Miyazaki Tsuneyuki , Sakai Hiroyasu , Kochi Takahiro , Kubota Masaya , Tanaka Takuji , Shimizu Masahito , Seishima Mitsuru
Published: July 2016

Overweight and obesity are becoming more prevalent worldwide. As the hepatic manifestation of the metabolic syndrome, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) have received attention as major causes of liver disorder. In addition, hepatocellular carcinoma (HCC) associated with NASH becomes an important issue. Although no standard medicinal treatment for NASH is established, pentoxifylline (PTX), a medicine used to improve circulation, is reported to ameliorate histopathological appearance of NASH and is thought to be a candidate therapeutic agent for NASH. In the present study, we investigated effects of PTX on NAFLD/NASH and the development of diethylnitrosamine (DEN)-induced liver tumorigenesis in monosodium glutamate (MSG)-treated mice, a novel mouse model of NASH-related hepatocarcinogenesis, and db/db obese and diabetic mice. Male MSG and db/db mice were administered DEN, and then they received drinking water containing PTX (100 mg/kg/day) throughout the experiment. At sacrifice, drinking water with PTX significantly inhibited the development of hepatic pre-neoplastic lesions compared with respective control groups. MSG mice were thought to be susceptible to liver tumorigenesis. Hepatic triglyceride contents in db/db mice were decreased by PTX administration. The serum levels of total cholesterol, triglyceride, free fatty acid, and alanine aminotransferase were all decreased by PTX treatment, as was the mRNA expression of pro-inflammatory cytokines (TNF-alpha and IL-1beta) the macrophage-inducing chemokine CCL2/MCP-1, and several lipogenic genes (FASN and SREBP1c) in the liver. In vitro studies also revealed that PTX treatment decreased the expression of several genes associated with de novo lipogenesis and CCL2/MCP-1 in hepatoma and hepatic stellate cell lines, respectively. These findings suggest that PTX prevents NAFLD/NASH-related liver tumorigenesis by attenuating chronic hepatic inflammation and decreasing lipogenic gene expression in the liver. PTX might be a promising and efficient agent for treatment of NAFLD/NASH patients, who have a higher risk for developing liver cancer.

Citation Format: Yohei Shirakami, Akinori Maruta, Koki Obara, Takayasu Ideta, Tsuneyuki Miyazaki, Hiroyasu Sakai, Takahiro Kochi, Masaya Kubota, Takuji Tanaka, Masahito Shimizu, Mitsuru Seishima. Preventive effects of pentoxifylline on hepatic tumorigenesis in a novel mouse model of NASH-related liver cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5239.
Abstract 614: Cytotoxic activity of enantia chlorantha, nauclea latifolia, and citrus medica extracts on carcinoma cells
Authors: Alford Chenel M. , Onyejiaka Alexandra , Myles Elbert L.
Published: July 2016

Over 562,340 Americans are expected to die of cancer, more than 1500 people a day. Cancer is the second most common cause of death in the US, exceeded only by heart disease. In the US, cancer accounts for nearly 1 of every 4 deaths. Our study focuses primarily on three plants never before investigated for antitumor activity. They were chosen based upon native ethno medicinal usages. Indigenous primarily to the southwestern region of Nigeria; Enantia chlorantha, Nauclea latifolia, and Citrus medica have all been traditionally used and studies have proven their noteworthy antibacterial, antimicrobial, and anti parasitical activities. These important characteristics provide the rationale behind studying these plants further for potential antitumor agents. Experimental: Methanolic leaf and bark extracts in a series of concentrations were taken from the previously stated plants and exposed to two breast and two colorectal cancer cells for 24 hours. Growth analysis is determined using a cell viability indicator alamar blue and a florescent plate reader. Results: Enantia chlorantha and Citrus medica demonstrated the most potential for containing novel antitumor compounds. However, E. chlorantha proved to be exceedingly toxic to the cellular proliferation of all four tumors cell lines at all concentrations. In addition to this, Nauclea latifolia extracts illustrated the least potential for antitumor activity. In most cases this extract showed little or no effect in reducing cellular proliferation. Conclusion: We conclude that leaf extracts from E. chlorantha and C. medica should be studied further to characterize their antitumor potential, investigate their main active compounds, and to better understand their mechanisms of action.

Citation Format: Chenel M. Alford, Alexandra Onyejiaka, Elbert L. Myles. Cytotoxic activity of enantia chlorantha, nauclea latifolia, and citrus medica extracts on carcinoma cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 614.
Abstract 615: Scaffold-based perfusion bioreactor system for in vitro maintenance of primary breast cancer tissue microenvironment suitable for personalized medicine
Authors: Muraro Manuele Giuseppe , Muenst Simone , Mele Valentina , Quagliata Luca , Tzankov Alexandar , Weber Walter P. , Spagnoli Giulio C. , Soysal Savas D.
Published: July 2016

INTRODUCTION Two-dimensional (2D) in vitro culture systems and in vivo animal models are the primary tools used to test cancer cell responses to drugs but they are not suited for the development of immune-mediate therapies. Here we present an innovative method for in vitro culture primary breast cancer (BrCa) tissues in porous 3D scaffolds by using a perfusion-based bioreactor system (U-CUP).

MATERIALS & METHODS Freshly excised breast cancer specimens were fragmented and cultured in a 3D “sandwich-like format” between collagen porous scaffolds under perfusion flow. DMEM/F12, supplemented with 10% autologous human serum, was used as a culture medium. Malignant and non-malignant cells survival, expansion into the scaffold and the ability to recapitulate features of the original BrCa specimens were histologically assessed. For estrogen receptor (ER) positive tissues we tested the response to hormonal therapy by adding the anti-ER drug Fulvestrant. Furthermore, the maintenance of immune-infiltrating cells allowed testing immune blockade therapy in vitro using anti PD-L1 on PD-L1 positive samples. Response to treatment was evaluated by histology and qRT-PCR for markers of immune-response.

RESULTS By culturing BrCa using the U-CUP we were able to preserve viability and to promote the expansion of breast cancer cells from surgical specimens together with accompanying stromal and immune cells into the porous scaffold. Expanding cancer cells were viable after 21 days and recapitulating the initial histology with formation of glands. Administration of anti-ER treatment was associated with decreased expansion of cancer tissue into the scaffold after 21 days. After 7 days of anti PD-L1 antibody treatment we observed a reduced number of tumor cells due to the activation of infiltrating lymphocytes, as shown by increased expression of IFNg and decreased expression of IL10.

CONCLUSIONS The scaffold-based perfusion bioreactor represents a successful organotypic tumor model allowing in vitro long-term culture of breast cancer specimens. Our findings shed the light on a promising system for selecting personalized treatment based on a patient's tumor specific microenvironment.

Citation Format: Manuele Giuseppe Muraro, Simone Muenst, Valentina Mele, Luca Quagliata, Alexandar Tzankov, Walter P. Weber, Giulio C. Spagnoli, Savas D. Soysal. Scaffold-based perfusion bioreactor system for in vitro maintenance of primary breast cancer tissue microenvironment suitable for personalized medicine. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 615.
Abstract 654: Impact of epithelial cell-specific deletion of mPGES-1 on colon carcinogenesis
Authors: Nakanishi Masako , Rosenberg Daniel W.
Published: July 2016

Activation of the COX-2/mPGES-1/PGE2 signaling axis is a hallmark of many cancers, including colorectal cancer (CRC), prompting the implementation of cancer prevention strategies targeting COX-2 activity. We have shown that targeting the downstream terminal PGE2 synthase, mPGES-1, specifically reduces inducible PGE2 formation without disrupting synthesis of other essential prostanoids. Additionally, global deletion of mPGES-1 (gKO) confers dramatic protection against intestinal cancer development in several mouse models, including the AOM+DSS inflammation-associated colon cancer model. Understanding the role of PGE2 under inflammatory conditions, however, is complicated by the diverse cellular sources and context-dependence of inducible PGE2. To clarify the relative contribution of inducible PGE2 synthesis within distinct cell compartments in colon, we have recently created an mPGES-1 conditional knockout mouse (cKO), where exon 3 of the mPGES-1 gene (mPtges) is floxed for tissue-specific Cre-mediated deletion. To test the role of epithelial-derived PGE2 synthesis on inflammation-associated cancer, we crossed the cKO mice with carbonic anhydrase 1 (Car1)-controlled Cre mice (cKO:Car1), thereby inactivating mPGES-1 function specifically within colonic epithelial cells. Based on our recent observation that global inactivation mPGES-1 sensitizes the colonic mucosa to direct environmental injury, we first examined the sensitivity of the cKO:Car1 mice to DSS-induced acute colitis. Two days after a five-day treatment with 0, 0.5 or 1% DSS, clinical signs of colitis, including the extent of colonic ulceration were determined. Both cKO:Car1 and cKO:WT control mice showed a comparable extent of colonic ulceration, covering ∼60% of the epithelial surface. We next examined the impact of epithelial-specific deletion of mPGES-1 on DSS-induced colon carcinogenesis. KO:Car1 and cKO:WT control mice were treated with a single injection of AOM (10 mg/kg bw) followed by five days of 0, 0.5 or 1% DSS, and colons were examined five weeks after the end of DSS treatment. Surprisingly, epithelial deletion of mPGES-1 in the cKO:Car1 mice failed to provide against cancer development in comparison to the cKO:WT mice. This is the first study to show that genetic inactivation of inducible PGE2 formation within a specific cell lineage (e.g. epithelial cells) does not affect both the extent of acute colonic inflammation nor subsequent inflammation-associated carcinogenesis.

Citation Format: Masako Nakanishi, Daniel W. Rosenberg. Impact of epithelial cell-specific deletion of mPGES-1 on colon carcinogenesis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 654.
Abstract 661: Establishment of transgenic mice with liver-specific BRAF V600E mutation
Authors: Tanaka Hiroki , Yamamoto Masahiro , Yamazaki Kosuke , Shimizu Keiko , Ogawa Katsuhiro
Published: July 2016

Diethylnitrosamine (DEN) is often used to induce hepatocarcinogenesis in rodents to investigate the pathogenesis of hepatocellular carcinoma (HCC). BrafV637E mutation, corresponding to the human BRAFV600E mutation, is highly frequent in DEN-induced hepatic tumors depending on mouse strains.

To investigate the role of BrafV637E mutation in DEN-induced hepatocarcinogenesis, we established the transgenic mice (Alb-Cre/BRAFV600E), in which human BRAFV600E mutation is specifically expressed in the liver, and compared the properties of DEN-induced hepatic tumors and the livers of the transgenic mice. The hepatic tumors were induced by neonatal treatment with DEN, isolated at various time points, and stored as frozen or paraffin-embedded materials. For production of the transgenic mice, we obtained homozygous male BRAFV600E mice, in which a LoxP-flanked cassette containing the human BRAF exons 15-18 cDNA, mouse polyadenilation sequences and the neo gene was inserted into the mouse Braf intron 14 upstream of the human BRAF exon 15 cDNA that encodes the BRAFV600E mutation, and crossed them with female Alb-Cre mice by in vitro fertilization.

RT-PCR and cDNA sequencing revealed that the liver of Alb-Cre/BRAFV600E mice expressed mRNA derived both from normal mouse and mutated human BRAF exon 15. The transgenic mice showed 20% decrease in body weight compared to normal mice, but 5 fold-increase in the liver/body weight. Histological examination revealed that the liver was entirely consisted of basophilic hepatocytes resembling to those in DEN-induced foci of cellular alteration at 8 weeks of birth, and bile duct cells were further increased at 10-12 weeks. The Ki-67 labeling index of hepatocytes in the Alb-Cre/BRAFV600E mice was 3 times higher than normal mice. Immunoblot analysis revealed that the liver of Alb-Cre/BRAFV600E mice expressed the BRAFV600E protein and showed hyperphosphlylation of ERK1 and AktS473 like the DEN-induced hepatic tumors. Furthermore, immunohistochemical staining detected increased C5/C5a expression in the hepatocytes of Alb-Cre/BRAFV600E mice, and by immunoblot analysis C5a, a protease-cleaved form of C5, was specifically detected in Alb-Cre/BRAFV600E liver like DEN-induced tumors. These results indicate that the liver specific expression of mutationally-activated BRAF led to the hepatocytic phenotype mimicking the DEN-induced hepatic tumors.

Citation Format: Hiroki Tanaka, Masahiro Yamamoto, Kosuke Yamazaki, Keiko Shimizu, Katsuhiro Ogawa. Establishment of transgenic mice with liver-specific BRAF V600E mutation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 661.
Abstract 74: Targeting nuclear export for triple-negative breast cancer therapy
Authors: Petrocca Fabio
Published: July 2016

Triple-negative breast cancers (TNBC) comprise the most aggressive subtype of breast cancer. They rapidly acquire resistance to chemotherapy and are also refractory to endocrine therapy and HER2 inhibitors. In fact, no targeted therapies are currently available against these tumors. Genome sequencing studies have shown that TNBCs are exceedingly heterogeneous in genetic mutations as well as copy number variations. Yet, TNBC almost invariably harbor inactivating mutations in TP53, which seems to be a crucial event in the pathogenesis of these tumors. We recently performed a series of siRNA lethality screens in vitro (N = 11 cell lines) to identify, in an unbiased way, recurrent vulnerabilities that could be harnessed as novel targets for TNBC therapy. Hits were genes whose silencing triggered massive cell death in ≥ 30% of TNBC lines tested. The screens re-discovered mitosis as a frequent Achilles’ heel of these tumors (antimitotic drugs are currently a mainstay of TNBC therapy), supporting the validity of the approach. The nuclear transport gene RAN also scored among the most frequent TNBC selective dependencies. Moreover, TNBC cell lines were exquisitely sensitive to selinexor (KPT-330), a first-in-class inhibitor of exportin 1 (XPO-1) currently in phase 2 trials, both in vitro and in vivo. TNBC cells treated with selinexor died of apoptosis. In contrast, normal human primary breast epithelial progenitors (BPE) underwent cell cycle arrest (but not death) upon selinexor treatment, and were able to resume proliferation upon drug removal. The efficacy of selinexor across different TNBC models varied, suggesting that additional factors, beside the TNBC status, are at play. Preliminary data based on a genome-wide CRISPR screen for genes and networks conferring sensitivity to selinexor using a p53-mutant TNBC cell line (MDA-MB-231) implicated a number of TP53-related genes as key mediators of response. Together, these data support the notion that p53-mutant TNBC coopt nuclear export function to silence TP53-associated networks and that XPO-1 inhibitors could be a viable strategy to tackle TNBC in the clinic.

Citation Format: Fabio Petrocca. Targeting nuclear export for triple-negative breast cancer therapy. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 74.
Abstract 743: Tyrosine kinase discoidin domain receptor-1 (DDR1) regulates cytotoxicity of recombinant immunotoxin for cancer therapy
Authors: Ali-Rahmani Fatima , Fitzgerald David , Martin Scott , Patel Paresma , Prunotto Marco , Ormanoglu Pinar , Thomas Craig , Pastan Ira
Published: July 2016

Discoidin domain receptor 1 (DDR1) is a collagen-activated tyrosine kinase that facilitates cell adhesion, migration, proliferation and matrix remodeling. The collagen/DDR1 axis is also thought to modulate tumor-stromal interaction and potentially affects tumor response to therapy. Mesothelin is a cell-surface protein over-expressed in several human cancers including mesothelioma, ovarian, lung, breast, and pancreatic cancers with limited expression on normal cells. RG7787 is a clinically optimized recombinant immunotoxin (RIT) consisting of a humanized anti-mesothelin Fab fused to domain III of Pseudomonas exotoxin A in which immunogenic B cell epitopes are silenced. To enhance therapeutic efficacy of RITs we conducted a kinome RNAi sensitization screen which identified DDR1 as a potential target. We hypothesized that DDR1 regulates RIT activity and its inhibition might enhance cell killing by RG7787. Knockdown of DDR1 by siRNA or treatment with inhibitor, ‘7rh’, greatly enhanced the cytotoxic activity of RG7787 in several cancer cell lines. Investigation into the mechanism of action showed DDR1 silencing was associated with a decrease in several ribosomal proteins and enhanced inhibition of protein synthesis. Induction of DDR1 expression or stimulation of DDR1 activity by collagen protected cancer cells from RG7787 killing, while DDR1 inhibition enhanced killing by RG7787. Moreover, the combination of immunotoxin and DDR1 inhibitor caused significantly more shrinkage of epithelial A431/H9 and pancreatic KLM1 tumor xenografts than either agent alone. These data demonstrate that DDR1 has a critical role in modulating immunotoxin activity. Inhibition of DDR1 represents a novel strategy to enhance therapeutic efficacy of RITs targeting mesothelin-expressing cancers.

Citation Format: Fatima Ali-Rahmani, David Fitzgerald, Scott Martin, Paresma Patel, Marco Prunotto, Pinar Ormanoglu, Craig Thomas, Ira Pastan. Tyrosine kinase discoidin domain receptor-1 (DDR1) regulates cytotoxicity of recombinant immunotoxin for cancer therapy. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 743.
Abstract 756: Myo-inositol modulates the tumor microenvironment in a mouse model of lung cancer chemoprevention
Authors: Unver Nese , Zeleke Kirubel T. , Tang Ximing , Holt Samantha , Moghaddam Seyed Javad M. , Wang Hong , Wistuba Ignacio I. , Hanash Samir M. , Ostrin Edwin J.
Published: July 2016

Background: Myo-inositol is a nutritional supplement that has been investigated as a chemopreventive agent for lung cancer. We have investigated the effect of myo-inositol in a CC-LR (CCSPCre/LSL-K-rasG12D) mouse lung cancer model. Blood, broncho-alveolar lavage fluid (BALF), and lungs were collected from CC-LR and LR littermate control mice at 14 weeks of age, when mice had a large number of premalignant lesions with only small foci of adenocarcinoma.

Methods: Lesion burden and stage was quantified using macroscopically evident lung surface tumor counts as well as histology from paraffin sections. Serial paraffin sections were also used for immunohistochemistry. Plasma was analyzed using high-sensitivity liquid-chromatography coupled tandem mass spectrometry. Cytokine and chemokine concentrations in BALF were quantitated using multiplex immunobead assays.

Results: Myo-inositol treated mice (n = 20) had fewer tumors (p < 0.0001) than mice raised on control diet (n = 23). Additionally, lesions were shifted towards lower grade, from adenomas and adenomatous alveolar hyperplasia to bronchial hyperplasia. Several host factors including cytokines and proteins produced by myeloid derived suppressor cells and macrophages were significantly impacted by myo-inositol treatment. In addition to changes in metabolic inflammation derived factors, proteins which are associated with both chronic inflammation and lung tumorigenesis were altered as well.

Conclusions: Myo-inositol treatment both reduced tumor burden and lesion grade in a KRAS model of lung cancer. Our findings of a substantial impact of myo-inositol treatment on the host response suggests novel mechanisms for its chemopreventive activitiy.

Citation Format: Nese Unver, Kirubel T. Zeleke, Ximing Tang, Samantha Holt, Seyed Javad M. Moghaddam, Hong Wang, Ignacio I. Wistuba, Samir M. Hanash, Edwin J. Ostrin. Myo-inositol modulates the tumor microenvironment in a mouse model of lung cancer chemoprevention. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 756.
Abstract 760: Identifying candidate genes that regulate tumor cell dormancy
Authors: Nini Ryan J. , El Touny Lara H. , Murgai Meera , Kaplan Rosandra N. , Green Jeffrey E.
Published: July 2016

Tumor cells disseminate from the primary tumor site early in the disease process. These disseminated tumor cells may remain dormant for years and later become proliferative to cause clinical recurrence and morbidity. The goal of this study is to better understand the biological and genetic mechanisms driving this dormant to proliferative switch. We have developed a 3D culture system using the dormant murine mammary tumor cell line, D2.0R. D2.0R cells remain dormant when cultured on basement membrane extract (BME), and exit dormancy when supplemented with collagen-1 (col-1). We have characterized the gene expression profile of these cells exiting dormancy in 3D through microarray analysis, and developed a fourteen-gene dormancy signature by profile cross-referencing this expression profile to a tumor cell dormancy signature developed by Kim, R.S. et al (PLOS ONE 2012). We hypothesize that knocking down expression of genes upregulated in proliferative cells will hinder the ability of D2.0R cells to break dormancy in 3D culture supplemented with collagen-1. We have validated three genes by qPCR and are screening these upregulated genes for biological effects on proliferation by short-hairpin RNA or molecular inhibition of D2.0R cells in our 3D model. We conclude that this signature will provide useful insight into genetic drivers of the dormant to proliferative switch and potential candidates as therapeutic targets in recurrent disease.

Citation Format: Ryan J. Nini, Lara H. El Touny, Meera Murgai, Rosandra N. Kaplan, Jeffrey E. Green. Identifying candidate genes that regulate tumor cell dormancy. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 760.
Abstract 779: The role of exosome-mediated cell-cell communication in inducing phenotypic changes
Authors: Lu Mingyang , Capello Michela , Tripathi Satyendra C. , Levine Herbert , Ben-Jacob Eshel , Hanash Samir M. , Onuchic José
Published: July 2016

A new class of intercellular communication has recently emerged that involves transfer of exosomes, especially during the interactions between tumor and the immune system. However, the advantage of exosome-mediated cell-cell communication over direct cell to cell communication mechanisms or through soluble factors is unclear. We have performed mass spectrometry based proteomic profiling of exosomes isolated from pancreatic cancer cell lines, for the exosome cell surface and for the protein cargo. The resulting profiles were compared with proteomic profiles of corresponding cell lysates. We uncovered substantial enrichment in protein pairs in exosomes across cell lines but not in cell lysates, suggestive of a mechanism of exosome-based protein sorting and packaging that favor specific protein combinations. Stochastic simulations and analytical analysis provide supportive evidence that exosomes enable recipient cells to rewire gene regulatory networks to induce robust phenotypic transitions among different gene states. Moreover, from the simulation of two-way exosome-mediated communication of two cell types, we show that cells could achieve synchronized decision making through exosomes. Our integrative approach provides new insights into unique features of exosome-mediated cell-cell communication.

Citation Format: Mingyang Lu, Michela Capello, Satyendra C. Tripathi, Herbert Levine, Eshel Ben-Jacob, Samir M. Hanash, José Onuchic. The role of exosome-mediated cell-cell communication in inducing phenotypic changes. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 779.
Abstract 828: α-Lipoic acid inhibits human hepatoma cell proliferation by Grb2-mediated downregulation of EGFR activity
Authors: Yang Lan , Lin Yuntao , Wen Ya , Sun XiaoJuan
Published: July 2016

Background: It has been reported that α-Lipoic acid (α-LA) as a naturally occurring anti-oxidant, suppresses the growth of hepatoma cells, but the mechanisms remains unclear.

Aims: To investigated whether α-LA inhibited hepatoma cells proliferation through EGFR-Grb2.

Methods and Results: The results showed that Hu7, Bel7402 and HepG2 proliferation were dramatically decreased after α-LA (2 mM) treatment for 24 and 48 hours, which were measured by CCK8 assay. Moreover, phosphorylation levels of EGFR was decreased by α-LA treatment, and its associated with an inhibition in cell-cycle transition. Next, we found that growth factor receptor bound protein 2 (Grb2), which is adaptor protein, was also significantly reduced by RT-PCR and western blot after α-LA treatment at 24 and 48 hours. Consistent with previous report, silenced of Grb2 dramatically blocked cell proliferation. To test whether the downregulation of Grb2 mediates α-LA induced proliferation inhibition, Grb2 was transfected into hepatoma cells to recover the reduction of Grb2 induced by α-LA. It was showed that overexpression of Grb2 also successfully inhibited α-LA induced decrease of cell proliferation. In addition, the data showed that phosphorylation levels of ERK1/2 was decreased by cell treated with α-LA. These results suggested that the Grb2 through binds to phosphorylated site in EGFR medicated α-LA suppress cell proliferation.

Conclusion: Our study showed α-LA inhibited cell proliferation through Grb2 suppressed phosphorylation levels of EGFR, ERK1/2 was involved in this pathway.

Citation Format: Lan Yang, Yuntao Lin, Ya Wen, XiaoJuan Sun. α-Lipoic acid inhibits human hepatoma cell proliferation by Grb2-mediated downregulation of EGFR activity. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 828.
Abstract 833: Benzyl isothiocyanate mediates glucose uptake through AKT activation in breast cancer cells
Authors: Roy Ruchi , Singh Shivendra V.
Published: July 2016

We have shown previously that benzyl isothiocyanate (BITC) administration retards the development of mouse mammary tumors driven by Her-2 oncogene proving in vivo evidence for its chemopreventive efficacy. However, we also observed an increase in glucose uptake by tumor in BITC treatment group compared with control mice. Proteomics using tumors from control and BITC-treated mice revealed changes in proteins related to metabolism. Thus, we studied the mechanism by which BITC increases glucose uptake using four cell lines with different genetic backgrounds (e.g., ER+, ER-, HER-2+, triple negative). Consistent with in vivo findings, BITC treatment enhanced the protein levels of glucose transporters (GLUT1 and GLUT4) regardless of ER, HER-2 or p53 status. On the other hand, lactate dehydrogenase (LDH) was downregulated in response to BITC treatment. Pyruvate kinase (PKM2) as well as tricarboxylic cycle (TCA cycle) related enzymes (IDH1, PDH, MDH) were upregulated in BITC treated cells compared with control. In agreement with these results, BITC treatment increased glucose, pyruvate, and acetyl-CoA levels but decreases lactate level. These results suggested that elevated glucose after BITC treatment was largely utilized through TCA cycle. Because AKT is known to regulate tumor metabolism including glycolysis and oxidative phosphorylation, we explored its involvement in BITC-mediated metabolic alterations. To our surprise, BITC treatment resulted in a marked increase in activation of AKT. Pharmacological inhibition of AKT antagonized BITC-mediated increase in GLUT1 expression as well as increase in glucose and pyruvate levels. In addition, AKT inhibition augmented BITC-mediated inhibition of cell survival (colony formation), induction of apoptosis, and suppression of migration in human breast cancer cells. Based on these findings, we propose that mammary cancer chemopreventive efficacy of BITC may be augmented by a combination regimen involving an AKT inhibitor. This study was supported by the grantCA129347 awarded by the National Cancer Institute.

Citation Format: Ruchi Roy, Shivendra V. Singh. Benzyl isothiocyanate mediates glucose uptake through AKT activation in breast cancer cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 833.
Abstract 841: Effect of equol on hormone-dependent rat mammary carcinoma induced by ethyl methanesulphonate (EMS)
Authors: ONO MISAKI , Higuchi Takako , Takeshima Mikako , Nakano Shuji
Published: July 2016

Soy isoflavones such as daidzein and its bioactive metabolite equol converted from daidzein by human intestinal bacterial flora, have been proposed to reduce the risk of breast cancer incidence in Asian women probably due to higher number of the inhabitants capable of producing equol in these countries. Although several in vitro studies shows the anti-cancer activity of equol against human breast cancer cells, there have been few reports that have directly showed the preventive role of equol in the experimental animal model of mammary carcinoma. We investigated here the effects of equol on the development of breast cancer using the EMS chemically induced rat model of hormone-dependent mammary carcinoma. Female WKA rats (n = 30) were equally divided into 2 groups, subsequently given EMS orally for 12 weeks and fed the CE2 diets with or without 50 mg equol/g diet throughout the experiments. All EMS-treated rats fed either diet developed ER- and/or PgR- positive hormone-dependent mammary carcinoma by 24 weeks. Compared with the equol-free diet, the diet supplemented with equol could not significantly delay the development of mammary carcinoma, showing any preventive activity on the development of EMS-induced hormone-dependent mammary carcinoma. The body weight, total EMS uptakes, and urine estradiol concentrations were not significantly different between these 2 groups. These data indicate that high dose administration of equol alone does not exert clear preventive effects on hormone-dependent EMS-induced mammary carcinogenesis, and may require other soy isoflavone components such as genistein that has previously been shown to exhibit a great synergy when combined with equol. The in vivo combination studies using genistein and equol are underway.

Citation Format: MISAKI ONO, Takako Higuchi, Mikako Takeshima, Shuji Nakano. Effect of equol on hormone-dependent rat mammary carcinoma induced by ethyl methanesulphonate (EMS). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 841.
Abstract 845A: Novel twin method estimates genetic prevalence of breast cancer
Authors: Baker Stuart G.
Published: July 2016

The standard twin method of the last one hundred years uses data from fraternal and identical twins to estimate heritability, which is the fraction of the variance attributed to genetic effects under an additive genetic model. Using the same data, the latent class twin method estimates a more easily interpretable quantity, the genetic prevalence, which is the fraction persons with an outcome who are in a genetic susceptibility latent class. A key assumption is that the genetic susceptibility latent class has relatively large independent probabilities of outcome as compared with an environmental susceptibility latent class with smaller and possibly dependent probabilities of outcome. Unlike the standard twin method which assumes additive genetic inheritance, the latent class twin method also allows for autosomal recessive, autosomal dominant inheritance. The method handles survival data by treating loss-to-follow up and death from competing risk as non-informative censoring. Applying this methodology to registry data from 45,000 pairs of Nordic twins, we estimated a genetic prevalence for breast cancer of only 1%. Because BRCA1 and BRAC2 have a combined prevalence of around 1%, there are likely no other high-penetrance genes contributing to breast cancer

Citation Format: Stuart G. Baker. Novel twin method estimates genetic prevalence of breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 845A.
Abstract 869: Meditope enablement and structural analysis of anti-CD33 antibodies
Authors: Dumitru Calin D. , Matho Michael , Gardiner Elisabeth , Williams John C. , Bzymek Krzysztof
Published: July 2016

Meditope Biosciences’ SnAP (Site-specific novel Antibody Platform) technology provides a novel and specific way to create antibody drug conjugates (ADCs). Cyclic peptides, termed ‘meditopes’, have been designed to selectively bind to a ‘meditope binding site’ engineered into the Fab of an antibody. The process of conferring meditope binding is referred to as “meditope enablement”. Enabling antibodies for meditope binding does not interfere with antigen recognition or antibody integrity due to the unique location of the binding site. Meditope peptide binding can be utilized to attach cytotoxic payloads to an enabled antibody in a specific and consistent manner, and has the potential to dramatically improve the consistency of ADC production. For advanced hematological cancers such as CD33 positive acute myeloid leukemia (AML), using an anti-CD33 monoclonal antibody conjugated to a potent cytotoxic agent may be a useful tumor reduction strategy, especially when patients have failed other treatments. To this end, meditope enablement of lintuzumab and gentuzumab permits a consistent, site-specific attachment of cytotoxins with a highly controllable drug antibody ratio (DAR). Structural and biophysical characterization of the meditope enabled anti CD33 antibodies has provided key insight to the meditope enablement process. Experiments confirm that payload conjugation and meditope peptide binding does not interfere with antibody integrity or antigen recognition. The meditope peptide drug complexes were tested in cell-based assays for CD33-targeted cell killing. Using X-ray crystallographic analysis and guided docking, we propose modifications to further enhance affinity of the meditope peptide conjugate : CD33 antibody interaction.

Citation Format: Calin D. Dumitru, Michael Matho, Elisabeth Gardiner, John C. Williams, Krzysztof Bzymek. Meditope enablement and structural analysis of anti-CD33 antibodies. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 869.
Abstract 884: NSD3-short is an adaptor protein that couples BRD4 to the CHD8 chromatin remodeler
Authors: Shen Chen , Ipsaro Jonathan J. , Shi Junwei , Vakoc Christopher R.
Published: July 2016

The bromodomain and extraterminal (BET) protein BRD4 is a therapeutic target in acute myeloid leukemia (AML). Here, we demonstrate that the AML maintenance function of BRD4 requires its interaction with NSD3, which belongs to a subfamily of H3K36 methyltransferases. Unexpectedly, AML cells were found to only require a short isoform of NSD3 that lacks the methyltransferase domain. We show that NSD3-short is an adaptor protein that sustains leukemia by linking BRD4 to the CHD8 chromatin remodeler, by utilizing a PWWP chromatin reader module, and by employing an acidic transactivation domain. Genetic targeting of NSD3 or CHD8 mimics the phenotypic and transcriptional effects of BRD4 inhibition. Furthermore, BRD4, NSD3, and CHD8 colocalize across the AML genome and are each released from super-enhancer regions upon chemical inhibition of BET bromodomains. These findings suggest that BET inhibitors exert therapeutic effects in leukemia by evicting BRD4-NSD3-CHD8 complexes from chromatin to suppress transcription.

Citation Format: Chen Shen, Jonathan J. Ipsaro, Junwei Shi, Christopher R. Vakoc. NSD3-short is an adaptor protein that couples BRD4 to the CHD8 chromatin remodeler. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 884.
Abstract 904: Heterozygous ATG7 inhibition enhances endocrine therapy responsiveness through regulation of damage associated molecular patterns and priming the immune system in ER+ breast tumors
Authors: Clarke Robert , Clarke Pamela A.G. , Wärri Anni , Cook Katherine L.
Published: July 2016

Breast cancer is the most prevalent cancer in women, with over 230,000 new cases diagnosed annually. The most common type of breast cancer, comprising over 70% of all cases, express the estrogen receptor (ER); these tumors are usually treated with an endocrine therapy such as an antiestrogen or aromatase inhibitor. Unfortunately, many of these tumors develop resistance, or in some instances express de novo resistance, which limits the curative potential of these therapies. Autophagy, a cellular process of “self-eating”, is implicated as possible contributor to endocrine therapy resistance in breast cancer. We previously showed that inhibiting autophagy through low-dose chloroquine treatment reversed antiestrogen therapy resistance in ER+ orthotopic breast tumors. We now show that heterozygous deletion of ATG7 decreased breast tumor multiplicity and increased endocrine targeting therapy sensitivity in a DMBA-model of ER+ mammary carcinogenesis. Knockdown of ATG7 through RNAi increased cytoplasmic to nuclear high-mobility group binding protein B1 (HMGB1) protein ratio, suggesting targeting ATG7 promotes damage associated molecular patterns (DAMP) signaling. Heterozygous deletion of ATG7 also increased cytoplasmic HMGB1 protein expression in tumor epithelial cells indicating targeting ATG7 promotes DAMP signaling in vivo. Furthermore, tumors from ATG7 heterozygous mice displayed increased CD68 staining indicating elevated macrophage infiltration. Corroborating previous literature showing the critical role of autophagy in T-cell maturation, splenic CD8+ T-cells were significantly reduced in tumor bearing ATG7 heterozygous mice. However, ATG7 heterozygous mice displayed increased tumor CD8+ T-cell population. These data suggest that while targeting ATG7 reduces overall circulating T-cell populations, inhibiting ATG7 enhances tumoral cytotoxic T-cell recruitment. Tumors from ATG7 heterozygous mice also showed a significant decrease in foxp3+ cells, indicating targeting ATG7 reduces immuno-suppressive T-reg population. Serum from ATG7 heterozygous mice showed increased circulating MDC, MCP-1, IL-6, and eotaxin cytokines. Taken together, these data suggests that ATG7 inhibition promotes an anti-tumor pro-inflammatory cytokine profile to enhance tumoral immune cell recruitment and promote endocrine therapy responsiveness.

Citation Format: Robert Clarke, Pamela A.G. Clarke, Anni Wärri, Katherine L. Cook. Heterozygous ATG7 inhibition enhances endocrine therapy responsiveness through regulation of damage associated molecular patterns and priming the immune system in ER+ breast tumors. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 904.
Abstract 962: Deregulated transcription of mouse satellite sequences accelerates oncogenic processes via functional inhibition of YBX1 protein
Authors: Kishikawa Takahiro , Otsuka Motoyuki , Koike Kazuhiko
Published: July 2016

Highly repetitive tandem arrays located at centromere and pericentromere regions of the chromosomes had been considered epigenetically silent by heterochromatin modification. However, the deregulated transcription of the non-coding satellite sequences exists in human and mouse pancreatic cancer tissues. This aberrant expression can be detected even in Kras-mutated pancreatic intraepithelial neoplasia (PanIN) tissues, which are pre-cancerous lesions to invasive pancreatic cancer. To examine the biological roles of these aberrantly expressed satellite RNAs during the carcinogenesis steps, we established genetically-modified mouse PanIN-derived cells, in which mouse major satellite (MajSAT) RNAs were ectopically expressed. MajSAT RNA expressing PanIN-derived cells showed the increased chromosomal instability and the rate of spontaneous point mutations in the genomic as well as in the mitochondrial DNAs. We identified YBX1 protein as a binding protein specifically with MajSAT RNA by RNA immunoprecipitation. MajSAT RNA inhibited nuclear translocation of YBX1 under oxidative damage, which reduced the DNA damage repair activity of YBX1. The mutation rate of genomic and mitochondrial DNAs, and transformation rate were rescued by YBX1 overexpression in these cells. These findings indicate that satellite transcripts at the early stage of cancer development may act as “mutagens” and accelerate oncogenic processes.

Citation Format: Takahiro Kishikawa, Motoyuki Otsuka, Kazuhiko Koike. Deregulated transcription of mouse satellite sequences accelerates oncogenic processes via functional inhibition of YBX1 protein. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 962.
Abstract 964: Circulating biomarker miRNA-150 promotes tumor cell proliferation and progression by targeting SRC kinase signaling inhibitor 1 (SRCIN1) in non-small cell lung cancer
Authors: Lin Jing , Zhang Liren , Ye Yuanqing , Oba Taro , Gentile Emanuela , Gentile Emanuela , Wang Jing , Zhao Yang , Gu Jian , Wistuba Ignacio , Roth Jack A. , Wu Xifeng , Ji Lin
Published: July 2016

Circulating microRNAs (c-miRNAs) expression ratio (ER) signatures were evaluated as prognostic biomarkers and therapeutic targets in early stage non-small cell lung cancer (NSCLC) patients. In a population study with 171 stage I and II NSCLC patients, the miR-150 and associated ER signature miR27A/miR-150 (ER ≥0.86, HR = 3.92, p = 1.46E-4) were significantly associated with 5-year survival. The upregulated expression of miR-150 was detected in primary tissue samples (n = 245) by miRNA microarray profiling analysis and significantly associated with cancer recurrence (p = 0.027) and overall survival (HR = 0.88, p = 0.04). Ectopic expression of miR-150 in NSCLC H1299, A549, and H2023 cells transfected by miR-150 expression plasmids promoted tumor cell proliferation, tumor cell-induced colony formation and migration/invasion, while blocking the action of miR-150 with a synthetic miR-150 inhibitor or transduction with a miRZip-150 inhibitor expressed by a lentiviral vector significantly inhibited these biological activities. The SRC kinase signaling inhibitor 1 (SRCIN1) was predicted to be a potential target of miR-150 by bioinformatics tools.miR-150-targeted binding and cleavage in the 3’-UTR of SRCIN1 mRNA were confirmed by a novel stem-loop array-reverse transcription-PCR assay. Both SRCIN1 gene and protein expression were significantly downregulated by ectopic expression of miR-150 and upregulated by miR-150 inhibitors in H1299 and H2023 NSCLC cells, as demonstrated by qRT-PCR and Western-blotting assays, respectively. Modulation of key elements in the SRCIN1 signaling pathway by ectopic expression or inhibition of miR-150 were further determined by qRT-PCR and predicted by ingenuity pathway analysis. Our findings suggest that circulating miR-150 and its associated ER signatures could serve as novel prognostic biomarkers for early stage NSCLC and function as an oncogenic miRNA that promotes lung cancer cell proliferation, invasion, and metastasis by direct targeting SRCIN1signaling pathway thus identifying SRCIN1 as a potential therapeutic target.

Citation Format: Jing Lin, Liren Zhang, Yuanqing Ye, Taro Oba, Emanuela Gentile, Emanuela Gentile, Jing Wang, Yang Zhao, Jian Gu, Ignacio Wistuba, Jack A. Roth, Xifeng Wu, Lin Ji. Circulating biomarker miRNA-150 promotes tumor cell proliferation and progression by targeting SRC kinase signaling inhibitor 1 (SRCIN1) in non-small cell lung cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 964.