bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 560: Distinct protein expression patterns of solid pseudopapillary neoplasm of pancreas
Authors: Park Minhee , Cho Minhee , Yoon SeongJu , Kim Hoguen
Published: May 2015

Solid pseudopapillary neoplasm (SPN), is an uncommon pancreatic tumor with distinct clinicopathologic features. SPNs are characterized by mutation in exon 3 of CTNNB1. However, little is known about SPN tumorigenesis but CTNNB1 mutation. In order to identify the characteristic gene expression patterns of SPN, we performed proteome analysis of SPN and compared to gene expression data. We analyzed pooled SPNs and pooled non-neoplastic pancreas tissues using LTQ-Orbitrap. In total, we identified 862 (444 up-regulated and 418 down-regulated) proteins showed differential expression in SPN compared to non-neoplastic pancreas. We compared proteome profiling compared to mRNA expression of SPNs, and then selected 544 significant proteins presented the same expressional tendency.

Many of the overexpressed proteins are related to the activated signaling pathways of SPN consistently with our previous study. Specifically, DKK4 (6.1-fold), APC (1.5-fold), RUVBL1 (1.4-fold) and β-catenin (1.3-fold) involved in Wnt signaling were up-regulated in protein level of SPNs compared to non-neoplastic pancreas. Besides Wnt signaling, we detected several up-regulated proteins including FUS and NONO. The interaction of β-catenin with FUS was reported that involved in the regulation of pre-mRNA splicing. We identified that FUS and NONO interacted directly with β-catenin by immunoprecipitation in β -catenin active cell lines (SW480, HCT116). We found that molecules involved in glycolysis, metabolism and sumoylation were activated in SPNs; HK1 (3.2-fold), PKM2 (3.3-fold), ENO2 (2.1-fold), PDHA (1.5-fold) and SUMO2 (1.6-fold). We also detected that several proteins involved in epithelial-mesenchymal transition were up or down-regulated including CTSB (3.98-fold), VIM (1.98-fold) and JUP (-2.29-fold).

Our proteomic profiling study of SPNs provides 1) SPN-specific molecular mechanism for solid-pseudopapillary neoplasm tumorigenesis similar with mRNA expression pattern including Wnt signaling, 2) SPN-specific epithelial-mesenchymal transition, and 3) a metabolism is activated in SPNs. These findings can be used for an early diagnosis biomarker development or molecular therapeutic target.

Citation Format: Minhee Park, Minhee Cho, SeongJu Yoon, Hoguen Kim. Distinct protein expression patterns of solid pseudopapillary neoplasm of pancreas. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 560. doi:10.1158/1538-7445.AM2014-560
Abstract 568: Few Carney's Triad patients have mutations in two subunits of the succinate dehydrogenase enzyme (SDHB, SDHC)
Authors: Boikos Sosipatros A. , Xekouki Paraskevi , Faucz Fabio R. , Pacak Karel , Raygada Margarita , Adams Karen , Szarek Evan , Ball Evan , Kim Su Young , Fumagalli Elena , Helman Lee J. , Carney J Aidan , Stratakis Constantine A.
Published: May 2015

Carney's triad (CTr) is a non-hereditary condition, primarily seen in young women, characterized by gastrointestinal stromal tumors (GIST), extra-adrenal paragangliomas and pulmonary chondromas. Most CTr patients present with GIST and pulmonary chondroma (incomplete CTr). A marked decrease in the enzymatic activity of succinate dehydrogenase (SDH) has been detected in these tumors, but the presence or absence of SDH mutations in CTr is controversial. A related disease, known as Carney-Stratakis Syndrome (CSS), has no female predisposition and presents with extra-adrenal paragangliomas and GIST tumors, without pulmonary chondromas. In distinction to CTr, CSS is hereditary due to germline SDH mutations in the enzyme's subunits (SDHA, SDHB, SDHC and SDHD) with corresponding decreased SDH activity in associated tumors. We have investigated 64 patients with CTr for germline mutations and/or deletions in the SDH subunit genes; four patients were found to have germline mutations in SDHB or SDHC. All four patients had multifocal gastric GIST and pulmonary chondromas at diagnosis; two subsequently developed paragangliomas, confirmed by biopsy. One of the patients with CTr and a SDHB mutation had a nephew with the same mutation and a neuroblastoma, confirming a previously reported association of neuroblastoma with gist (JMG 2009; 46:215, and AJMG 2010; 152A: 1531). We conclude that few CTr patients maybe more correctly classified as having CSS; the genetic distinction of CTr from CSS needs further study.

[S.A.B. and P.X. should be regarded as joint first authors.]

Citation Format: Sosipatros A. Boikos, Paraskevi Xekouki, Fabio R. Faucz, Karel Pacak, Margarita Raygada, Karen Adams, Evan Szarek, Evan Ball, Su Young Kim, Elena Fumagalli, Lee J. Helman, J Aidan Carney, Constantine A. Stratakis. Few Carney's Triad patients have mutations in two subunits of the succinate dehydrogenase enzyme (SDHB, SDHC). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 568. doi:10.1158/1538-7445.AM2014-568
Abstract 584: NVP-BEZ235 decreases mutant p53 and downregulates miR-23a-24-27a to inhibit metastasis in breast cancer cells
Authors: Wang Dongsheng , Du Qin , He Binfeng , Deng Yibin , Guo Xiaolan
Published: May 2015

Nearly half of human cancers harbor TP53 mutations, which are predominantly through missense mutations that result in accumulation of mutant p53 proteins in cancer cells. More and more findings indicate that the mutant p53 proteins acquire gain-of-function abilities to promote carcinogenesis, metastasis, tumor recurrence and chemoresistance. TP53 mutations are the most frequent genetic alterations in breast cancer, observed in 30% of breast carcinomas, especially the triple negative breast cancer (TNBC),which most easily metastasizes and confers chemoresistance. Therefore targeting TP53 mutation in breast cancer might be another promising approach of therapeutics. Our previous investigation showed that the AKT-mTOR dual inhibitor, NVP-BEZ235(called BEZ235 thereafter), could inhibit AKT-mTOR pathway activation, most interestingly mutant p53 was significantly reduced with BEZ235 treatment(unpublished data). In this study, three TNBC cell lines MDA-MB-231, MDA-MB-436, MDA-MB-468 as TP53 mutation group and MCF-7 as control were employed with BEZ235 treatment at different dosages and time points. We found that AKT-mTOR signaling pathway were highly activated in these TNBC cells but were inhibited obviously after BEZ235 treatment; most importantly, mutant p53 in these TNBC cells decreased significantly, but rare changes were detected in MCF-7 cells with BEZ235 treatment. Interestingly, we found miR-23a-24-27a cluster was about 2 fold upregulation in TNBC cells after BEZ235 treatment while exploring the decline of p53 by detecting microRNAs expression in those cell lines. To address whether BEZ235 could affect the metastasis ability of TNBC cells, cell invasion assay Transwell was used to measure the invasiveness of TNBC cells with BEZ235, and we observed that BEZ235 could inhibit the metastasis of TNBC cells, on the other hand miR-23a-24-27a cluster mimics could also induce the inhibition of metastasis in TNBC cells. Our results suggest that BEZ235 might target mutant p53 accumulation and downregulate miR-23a-24-27a cluster to inhibit the metastasis abilities of triple negative breast cancer cells, which might provide an important direction to further study the breast cancer harboring mutant p53, and also have promising therapeutic benefits for cancer patients carrying such p53 mutations.

Citation Format: Dongsheng Wang, Qin Du, Binfeng He, Yibin Deng, Xiaolan Guo. NVP-BEZ235 decreases mutant p53 and downregulates miR-23a-24-27a to inhibit metastasis in breast cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 584. doi:10.1158/1538-7445.AM2014-584
Abstract 589: DNA demethylating agent and histone deacetylation inhibitor synergistically induce paired box 5 gene expression in non-small cell lung cancer cell lines
Authors: Liang Yuanxin , Perez-Soler Roman , Zou Yiyu
Published: May 2015

Epigenetic abnormalities play an important role in carcinogenesis and tumor suppressor paired box 5 gene (Pax5) is one of the most frequently methylated genes in non-small cell lung cancer (NSCLC). Depletion of Pax5 increased malignant characteristics including proliferation, migration and invasion in mammary cancer cells, while overexpression of Pax5 does not lead to cancer in vivo and induces apoptosis in hematological cancer cells. In this study, we found that Pax5 expression was frequently absent or down-regulated in NSCLC cell lines in vitro. We tested whether a combination of DNA demethylating agent Azacytidine and histone deacetylation (HDAC) inhibitor Vorinostat has a synergistic effect on the Pax 5 gene expression and cell growth inhibition of human NSCLC cell lines. We found that the combination induced Pax5 expression synergistically in NSCLC cell lines. Azacytidine decreased global DNA methylation and reduced CpG sites methylation rate in Pax5 promoter region. Vorinostat inhibited HDAC activity, but did not directly enhance the demethylation function of Azacytidine. Further investigation is needed to uncover the mechanism of action of the synergistic effect of these two agents on the Pax5 gene expression. Our results also show that different NSCLC cell lines respond similarly to the combination treatment under our experimental conditions.

Citation Format: Yuanxin Liang, Roman Perez-Soler, Yiyu Zou. DNA demethylating agent and histone deacetylation inhibitor synergistically induce paired box 5 gene expression in non-small cell lung cancer cell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 589. doi:10.1158/1538-7445.AM2014-589
Abstract 591: LKB1 regulates COX-2 transcription via CRTCs dependent pathway
Authors: Cao Chunxia , Gao Ruli , Zhang Min , Chen Zirong , Wu Lizi , Kaye Maria Zajac , Kaye Frederic
Published: May 2015

Inactivation of the liver kinase B1 (LKB1) gene by somatic mutation is a common event in lung adenocarcinoma. LKB1 was first identified as a tumor suppressor responsible for Peutz-Jeghers syndrome (PJS) and up regulation of cyclooxygenase-2 (COX-2) was detected in a significant percentage of human PJS polyps. In addition, COX-2 has been proposed as a therapeutic target for lung cancer although clinical trial using COX-2 inhibitors have been disappointing.

In the current study, we identified a novel LKB1/CRTC/COX-2 molecular pathway in human lung cancer cells and provided new information for clinical use of COX-2 inhibitors. The Kaye lab cloned the CREB-regulated transcription co-activators (CRTCs) and showed aberrant phosphorylation and activation of CRTC1 exclusively in non-small cell lung cancer (NSCLC) samples carrying LKB1 null mutations. We have now demonstrated that CRTC directly regulates COX-2 expression via evolutionarily conserved CRE sites within the promoter. In addition, we observed that ectopic expression of LKB1 resulted in nuclear export of phosphorylated CRTC with attenuation of COX-2 expression. Alternatively, LKB1 knock-down results in CRTC activation and promotes COX-2 expression in NSCLC cells. Importantly, LKB1 null lung cancer cells were preferentially sensitive to COX-2 inhibitors. In summary, our data defines a CRTCs-mediated transcriptional regulatory mechanism for COX-2 activity in cancer and proposes a possible clinical application of COX-2 inhibitors in patients with lung tumors carrying somatic LKB1 null mutations.

Citation Format: Chunxia Cao, Ruli Gao, Min Zhang, Zirong Chen, Lizi Wu, Maria Zajac Kaye, Frederic Kaye. LKB1 regulates COX-2 transcription via CRTCs dependent pathway. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 591. doi:10.1158/1538-7445.AM2014-591
Abstract 601: Essential role of LRF in mesenchymal stem cell differentiation and tumorigenesis through Dlk1 and Sox9 repression
Authors: Guarnerio Jlenia , Lunardi Andrea , Pandolfi Pier Paolo
Published: May 2015

The regulatory factors governing the initial steps of mesenchymal stem cell (MSC) commitment and differentiation are largely unknown, and the role of MSCs in the genesis of mesenchymal tumors (sarcomas) has not been fully elucidated. In recent years, several genes and pathways have been characterized as important regulators of these cells’ differentiation into adipocytes, chondrocytes and osteoblasts. Although extremely valuable, these data have been mainly generated using cell lines or mouse embryonic fibroblasts (MEFs), leaving a more reliable model, such as one based on primary multi-potent MSCs, completely unexplored. To fill this gap, we have established new conditions enabling us to manipulate in vitro primary MSCs while maintaining their stemness properties, and have taken advantage of a series of genetically engineered mouse models to unravel a new role for LRF as both a master regulator of MSC differentiation and a tumor suppressor gene in mesenchymal tumors through the repression of two major pathways: DLK1/MAPK and SOX9. Mesenchymal tumors, although rare, have an extremely high rate of mortality, due to a lack of knowledge of the molecular mechanisms responsible for their genesis and progression, and consequently a limited number of available drugs. Our recent findings, however, significantly advance our knowledge of the mechanisms underlying sarcoma pathogenesis, and identify new LRF/DLK1/MAPK and LRF/SOX9 pathways that could prove fundamental to the stratification and targeted therapy of LRF-negative sarcomas.

Citation Format: Jlenia Guarnerio, Andrea Lunardi, Pier Paolo Pandolfi. Essential role of LRF in mesenchymal stem cell differentiation and tumorigenesis through Dlk1 and Sox9 repression. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 601. doi:10.1158/1538-7445.AM2014-601
Abstract 629: Combination hypoxia-specific chemotherapy and immunotherapy of prostate cancer
Authors: Ai Midan , Bartkowiak Todd , Jaiswal Ashvin R. , Shah Krishna , Ager Casey , Lerman Beatrisa , Curran Michael A.
Published: May 2015

Tumor hypoxia contributes to chemotherapy and radiotherapy resistance, and helps foster metastasis. Hypoxia likely also supports tumor immune resistance by supporting development of suppressive myeloid and T cell populations by activating immunosuppressive signaling pathways in the tumor and stroma, and by creating a metabolically hostile environment for immune effector cells. TH-302 is a hypoxia-specific chemotherapeutic drug which is activated only in the hypoxic cores of tumors and remains harmless in the periphery. We hypothesized that concurrent combination therapy with TH-302 and T cell checkpoint blockade would promote inside-out tumor destruction with the drug killing at the core, releasing antigen, and diminishing suppression, while the antibodies helped expand and protect the T cells activated as a result. In the TRAMP-C2 prostatic adenocarcinoma model, we found that antibody blockade of CTLA-4 and PD-1, used in conjunction with TH-302 administration, promoted tumor rejection in a significantly larger percentage of mice than either therapy alone. The combination therapy promoted uniquely advantageous ratios of effector T cells to MDSC within the prostate cancer microenvironment. This novel combination of immunotherapy and hypoxia-specific chemotherapy has the potential to offer profound anti-tumor responses to a much greater percentage of patients than either chemotherapy or immunotherapy alone with the same or fewer side effects.

Citation Format: Midan Ai, Todd Bartkowiak, Ashvin R. Jaiswal, Krishna Shah, Casey Ager, Beatrisa Lerman, Michael A. Curran. Combination hypoxia-specific chemotherapy and immunotherapy of prostate cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 629. doi:10.1158/1538-7445.AM2014-629
Abstract 654: Targeting K-ras mutant cancer cells with a lupus anti-guanosine antibody
Authors: Young Melissa R. , Noble Philip W. , Weisbart Richard H. , Hansen James E.
Published: May 2015

Aberrant G-protein signaling due to mutations in genes encoding the Ras family of small GTPases is associated with approximately 30% of human cancers, and K-ras is one of the most commonly mutated Ras proteins. Development of targeted therapies that are preferentially toxic to cancer cells harboring K-ras mutations is therefore an important goal in cancer research. We have identified an unusual cell-penetrating lupus autoantibody, 4H2, as a potential candidate for development as a targeted therapy for tumors with activating K-ras mutations. 4H2 is an anti-guanosine antibody that has previously been shown to penetrate living cells and inhibit cAMP formation. Taken together, the ability of 4H2 to bind guanosine (a component of GDP/GTP) and to inhibit cAMP formation suggests that 4H2 perturbs G-protein signaling. We therefore hypothesized that 4H2 would be selectively toxic to cancer cells with aberrant G-protein signaling due to activating K-ras mutations compared to cells without mutations in K-ras. To test this hypothesis, we evaluated the effects of 4H2 on a panel of isogenic pairs of cells with and without activating K-ras mutations, including Cal12T lung cancer cells (with and without a G12C activating K-ras mutation), NCI-H1975 lung cancer cells (with and without a G12D activating K-ras mutation), and SW48 colon cancer cells (with and without a G12A activating K-ras mutation). Immunofluorescence experiments confirmed that 4H2 penetrates into and localizes to the cytoplasm of cells with and without an activating K-ras mutation. In cell proliferation assays the matched pairs of cells were treated with 4H2 while growing as subconfluent monolayers, and 4H2 was observed to significantly inhibit the proliferation of the cells with activating K-ras mutations but not the cells without K-ras mutations. Next, colony formation assays confirmed that treatment with 4H2 was significantly more toxic to cells with activating K-ras mutations compared to cells without K-ras mutations. Mechanistically, Western blot analyses suggest a differential effect of 4H2 on the MAP kinase and Akt signaling pathways in K-ras mutant and wild type cells, consistent with the hypothesis that 4H2 interferes with G-protein associated intracellular signaling pathways. In summary, this work has demonstrated that 4H2 is an intriguing candidate for further study and development as a potential targeted therapy for tumors with activating mutations in K-ras.

Citation Format: Melissa R. Young, Philip W. Noble, Richard H. Weisbart, James E. Hansen. Targeting K-ras mutant cancer cells with a lupus anti-guanosine antibody. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 654. doi:10.1158/1538-7445.AM2014-654
Abstract 671: CD38-specific engineered toxin body: Therapeutic potential for multiple myeloma
Authors: Rajagopalan Sangeetha , Brieschke Brigitte , Robinson Garrett L. , Erdman Jennifer , Null William , Higgins Jack P. , Willert Erin K.
Published: May 2015

Multiple myeloma is a malignancy of plasma cells that accounts for 10% of all hematological cancers. Current treatments for multiple myeloma include immunomodulatory agents, protease inhibitors and chemotherapies and, while these therapies are often initially effective, most patients experience relapse. New therapeutics are urgently required. CD38 is a transmembrane glycoprotein absent on most resting leukocytes but expressed on lymphoid malignancies, including multiple myeloma and lymphoma, making it an attractive target for directed therapy. Recent clinical trials with antibodies to CD38 have shown promise in multiple myeloma. While these antibodies rely on the recruitment of an immune response for cytotoxicity, we have developed an engineered toxin body (ETB) comprising a CD38 binding scFv and a de-immunogenized form of Shiga-like Toxin A (MT-4001) capable of specifically recognizing and directly killing CD38 expressing cells. Our results show that MT-4001 is a promising targeted therapeutic agent against CD38 positive cancer cells and is currently under further development.

Citation Format: Sangeetha Rajagopalan, Brigitte Brieschke, Garrett L. Robinson, Jennifer Erdman, William Null, Jack P. Higgins, Erin K. Willert. CD38-specific engineered toxin body: Therapeutic potential for multiple myeloma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 671. doi:10.1158/1538-7445.AM2014-671
Abstract 672: Pharmacokinetic and pharmacodynamic (PK/PD) modeling of preclinical data of a novel anti-fibroblast growth factor receptor 2(FGFR2) antibody (BAY 1179470) to guide dosing in Phase 1
Authors: Wittemer-Rump Sabine , Kopitz Charlotte , Huynh Hung , Lindbom Lars , Beckermann Bernhard , Osada Motonobu , Laurent Dirk , Lippert Jörg
Published: May 2015

BAY 1179470 is a human immunoglobulin (IgG) antibody directed against fibroblast growth factor receptor 2 (FGFR2). FGFR2 is overexpressed on cancer cells during tumorigenesis and metastasis. Anti-tumor efficacy of BAY 1179470 has been demonstrated in FGFR2-expressing gastric cancer mouse and rat xenograft models. No toxicologically relevant findings were observed in the repeated dose preclinical safety studies in rats and monkeys. Therefore, toxicity was not an appropriate endpoint for the first-in-man (FIM) study and dose selection was decided to be based on PK/PD modeling and predictions from preclinical efficacy data. All preclinical PK and tumor response data from mouse models were used to create a model framework to describe the PK and PK/PD as functions of BAY 1179470 dose, regimen and time. In a subsequent confirmatory step the PK/PD model derived from mouse efficacy data was applied to predict the efficacy in rats. Human PK parameters based on scaling from monkey were used to predict PK profiles in humans for a range of doses and schedules. These sets of predicted exposure were combined with the PK/PD model developed from mouse models to assess the expected efficacy for a range of human tumor doubling rates. Minimal effective doses, maximum effect and maximum effect doses, and maximal effective doses in humans were derived for various dosing intervals (1 day to 6 weeks). From the maximum effect dose the target AUC in humans was calculated and doses for the FIM study selected accordingly. The FIM study is currently ongoing in Japan (NCT01881217).

Citation Format: Sabine Wittemer-Rump, Charlotte Kopitz, Hung Huynh, Lars Lindbom, Bernhard Beckermann, Motonobu Osada, Dirk Laurent, Jörg Lippert. Pharmacokinetic and pharmacodynamic (PK/PD) modeling of preclinical data of a novel anti-fibroblast growth factor receptor 2(FGFR2) antibody (BAY 1179470) to guide dosing in Phase 1. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 672. doi:10.1158/1538-7445.AM2014-672
Abstract 694: Different pancreatic cancer cells have their own core signaling pathway
Authors: Kim Eunkyung , Kang Sujin , Kim So Y. , Kang Dongxu , Lee Seungha , Choi Hye J. , Kim Joo-Hang , Song Jae Jin
Published: May 2015

Gemcitabine as the standard chemotherapy agent to pancreatic cancer has proved effective; however, the response rate remains at 5.4% and the 5-year survival rate is extremely poor. Due to the shortcomings of gemcitabine and the presence of gemcitabine-resistant pancreatic cancer, the development of targeted agents into an anti-neoplastic agent remains a viable option.

We have investigated the transforming growth factor-beta (TGF-β), which is known to play a central role in pancreas cell function. We have already observed that the suppression of TGF-β2 induced an unexpected down-regulation of both TGF-β1 and TGF-β3 with concomitant decreases of survival-related signals, such as N-caderin, β-catenin, pp65 in melanoma cell line. Here, two different pancreatic cancer cell lines (HPAC, BxPC3), which have opposite genetic backgrounds (K-ras, p53, Smad4, EGFR), have shown differing sensitivities to the down-regulation of TGF-β2. Through transcriptome analysis, HPAC showed a high expression of TGF-β2, MUC4, HSP27, BMP4 which are deeply related to tumor progression and metastasis and are composed to core signaling complex initiating from TGF-β2. This was confirmed by TGF-β2 down-regulation with gemcitabine to show a greater decrease in survival potential compared to BxPC3. On the contrary, BxPC3, which has more of the mutant type p53, exhibited greater down-regulation of MUC4 by downregulation of p53 compared to that of TGF-β2. Such observations suggest that BxPC3 is composed of a different core signaling pathway, p53-MUC4 rather than TGF-β2-related signalings.In conclusion, it is necessary that the core signaling pathways which are implicated in individual pancreatic carcinogenesis are more specifically considered so that the various gemcitabine-resistant pancreatic cancer cells on the basis of customized treatment can be controlled.

Citation Format: Eunkyung Kim, Sujin Kang, So Y. Kim, Dongxu Kang, Seungha Lee, Hye J. Choi, Joo-Hang Kim, Jae Jin Song. Different pancreatic cancer cells have their own core signaling pathway. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 694. doi:10.1158/1538-7445.AM2014-694
Abstract 703: Highly selective HSV virotherapy for glioblastoma
Authors: Li Aofei , Marzulli Marco , Mazzacurati Lucia , Uchida Hiroaki , Cohen Justus , Glorioso Joseph , Grandi Paola
Published: May 2015

Glioblastoma Multiforme (GBM) is an aggressive brain cancer for which there is no effective treatment. Oncolytic HSV vectors (oHSV) are attenuated lytic viruses that have shown promise in the treatment of human GBM models in animals. Although proven safe for treatment of GBM in patients, oHSVs efficacy has been limited, a consequence of poor intra-tumoral virus replication and spread. To counter these limitations, we have developed oHSVs whose selective replication in GBM cells does not rely on defective genes. This was accomplished by (i) full retargeting of oHSV to utilize the epidermal growth factor receptor (EGFR) for infection of human GBM tumor cells and (ii) further vector engineering to modify the essential HSV immediate early gene (ICP4) for sensitivity to repression by the microRNA mir-124. Mir-124 is highly expressed in neurons but virtually absent in GBM and highly conserved among different species. The mir-124-regulated vector was unable to replicate in nude mice following intracranial inoculation supporting vector safety and was shown to be effective in the treatment of human GBM in nude mice. To enhance vector intra-tumor vector spread, our EGFR retargeted-mir-124 controlled vector was further modified by vector arming with the matrix metalloproteinase gene encoding MMP9. MMP9 degrades collagen type IV, a major component of the extracellular matrix (ECM) and basement membranes of glioblastomas but absent in normal brain tissue. Studies are ongoing to determine whether MMP9 expression enhances vector spread in GBM neurospheres and as a therapeutic agent for enhanced treatment of human GBM in animals

Citation Format: Aofei Li, Marco Marzulli, Lucia Mazzacurati, Hiroaki Uchida, Justus Cohen, Joseph Glorioso, Paola Grandi. Highly selective HSV virotherapy for glioblastoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 703. doi:10.1158/1538-7445.AM2014-703
Abstract 707: Tumor-targeted delivery of siRNA using stabilized calcium phosphate nanoparticles based on bio-inspired hyaluronic acid conjugate
Authors: Lee Min Sang , Lee Jung Eun , Byun Eunkyoung , Kim Nak Won , Lee Haeshin , Jeong Ji Hoon
Published: May 2015

Purpose : Low cytotoxicity and high cellular gene delivery capability are among the most important prerequisites for the selection of a non-viral carrier. In this study, we report the development of calcium phosphate (CAP) nanoparticles stabilized by a conjugate of the biological adhesive molecule, 3,4-dihydroxy-L-phenylalanine (dopa), and a nontoxic hydrophilic natural polymer, hyaluronic acid (HA), for targeted siRNA delivery to cancer cells.

Methods : Dopa-conjugated HA (dopa-HA) was synthesized by EDC/NHS chemistry and analyzed by spectrometry and 1H-NMR. Stabilized calcium phosphate nanoparticles containing siRNA (CAP/siRNA/dopa-HA) was prepared by simply mixing CaCl2 solution containing siRNA with a HEPES buffer containing Na2HPO4 and subsequent addition of a solution containing dopa-HA. The particles were characterized by using light scattering method and transmission electron microscope (TEM). The gene silencing and cancer cell-targeting ability of CAP/siRNA/dopa-HA was evaluated by monitoring cellular reporter activity (luciferase) in human colon carcinoma cells permanently expressing firefly luciferase. Confocal microscopy and FACS analysis were performed to assess CD44-specific cellular delivery. Bio-distribution and in vivo gene silencing of CAP/siRNA/dopa-HA nanoparticles were studied in an animal model bearing tumor xenograft.

Results : CAP/siRNA/dopa-HA can form compact nanoparticles that effectively protect siRNA from enzymatic degradation despite the structural drawbacks of siRNA, such as low charge density and short and rigid structure. In addition, stabilized CAP nanoparticles were able to maintain their colloidal stability in a physiological salt condition for over a week. The superior ability of CAP/siRNA/dopa-HA to maintain the integrity of encapsulated siRNA and the stability in solution of the nanoparticles allow this formulation to achieve improved intratumoral accumulation of siRNA and a high level of target gene silencing in solid tumors after systemic administration.

Conclusion Considering its biocompatibility, transfection efficacy, and tumor targeting capability, this stabilized organic-inorganic hybrid gene delivery platform should be considered a promising candidate carrier for systemic siRNA delivery and targeted cancer therapy.

Citation Format: Min Sang Lee, Jung Eun Lee, Eunkyoung Byun, Nak Won Kim, Haeshin Lee, Ji Hoon Jeong. Tumor-targeted delivery of siRNA using stabilized calcium phosphate nanoparticles based on bio-inspired hyaluronic acid conjugate. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 707. doi:10.1158/1538-7445.AM2014-707
Abstract 710: The efficacy of tumor-targeting Salmonella typhimurium A1-R on bone metastasis
Authors: Miwa Shinji , Zhao Ming , Yano Shuya , Zhang Yong , Uehara Fuminari , Matsumoto Yasunori , Hiroshima Yukihiko , Yamamoto Mako , Kimura Hiroaki , Hayashi Katsuhiro , Tsuchiya Hiroyuki , Hoffman Robert M.
Published: May 2015

We have previously developed a genetically-modified bacterial strain of Salmonella typhimurium (A1-R), which expresses GFP. In this study, we measured the efficacy of A1-R on breast cancer bone metastasis. We established an early-stage bone-metastasis model in nude mice by cardiac injection and a late-stage model by injection into the intramedullary cavity of the tibia using MDA-MB-435 human breast cancer cells (Human breast cancer cell lines co-express neuronal, epithelial, and melanocytic differentiation markers in vitro and in vivo. PLoS One 5, e9712, 2010). Both mouse models of bone metastasis were treated with A1-R. Fluorescence imaging of the mice was performed to visualize the metastatic bone lesions. In a first set of experiments, we showed that A1-R invaded and replicated intracellularly in MDA-MB-435-GFP cells in vitro. A1-R dose-dependently inhibited proliferation of MDA-MB-435-GFP cells. In the early-stage bone-metastasis model, A1-R significantly improved metastasis-free survival. In the advanced-stage bone-metastasis model, A1-R significantly inhibited the growth of the metastatic lesions. These data indicated that A1-R is useful to prevent and inhibit the growth of metastatic breast cancer bone tumors.

Citation Format: Shinji Miwa, Ming Zhao, Shuya Yano, Yong Zhang, Fuminari Uehara, Yasunori Matsumoto, Yukihiko Hiroshima, Mako Yamamoto, Hiroaki Kimura, Katsuhiro Hayashi, Hiroyuki Tsuchiya, Robert M. Hoffman. The efficacy of tumor-targeting Salmonella typhimurium A1-R on bone metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 710. doi:10.1158/1538-7445.AM2014-710
Abstract 716: ASPH_0047: a potent and selective antisense oligonucleotide-targeting transforming growth factor beta 2 (TGF-β2)
Authors: Wosikowski Katja , Jaschinski Frank , Kohonen Hanna , Braun Stephan , Leo Eugen , Janicot Michel
Published: May 2015

Transforming growth factor beta (TGF-β) is a key member of a large family of cytokines, including bone morphogenetic protein (BMP), nodals, activins and others, which play critical, pleiotropic roles in the pathophysiology of various human diseases, such as cancer, inflammation, autoimmune disease, and cirrhosis/fibrosis. In particular, the different TGF-β isoforms (TGF-β1, -β2, and -β3, encoded by different genes but sharing high sequence and structure homology) are overexpressed in many human tumors. Correlations between TGF-β expression, cancer stage and clinical parameters have been reported and linked to poor clinical outcome. TGF-β has been associated with a wide range of tumor-promoting processes, including tumor cell invasion and migration, angiogenesis, immunosuppression, as well as tumor stem cell maintenance and protection. Therefore, blocking the TGF-β signaling pathway via inhibition of TGF-β expression appears as an attractive therapeutic intervention in Oncology.

We have previously reported the rational design and preliminary outcome of an extensive discovery program for identification of antisense oligodeoxynucleotides targeting the various TGF-β isoforms. We present here ASPH_0047, a 17-mer LNA-modified gapmer based on the sequence of the human TGF-β2 mRNA, as novel preclinical development candidate. ASPH_0047 shows potent and selective target downregulation (mRNA and protein) in various cell-based assays. Preliminary preclinical biodistribution studies in rodent point at tissue penetration in expected target organs (e.g., liver, kidney, spleen) and accumulation in tumor tissue consistent with observed target downregulation and efficacy in relevant in vivo experimental antitumor models. Key pharmacology properties and preclinical features of ASPH_0047 supporting rapid advancement to clinical development will be presented.

Citation Format: Katja Wosikowski, Frank Jaschinski, Hanna Kohonen, Stephan Braun, Eugen Leo, Michel Janicot. ASPH_0047: a potent and selective antisense oligonucleotide-targeting transforming growth factor beta 2 (TGF-β2). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 716. doi:10.1158/1538-7445.AM2014-716
Abstract 727: Does gene transfer of gulono-lactone oxidase into human hepatocellular carcinoma cells restore ascorbate biosynthesis
Authors: Flett Teresa , Campbell Elizabeth , Phillips Elisabeth , Vissers Margreet CM , Dachs Gabi U.
Published: May 2015

Humans are unable to synthesise ascorbate (vitamin C) due to a mutation in the gene for gulono-lactone oxidase (Gulo), the terminal enzyme in the synthesis pathway. Ascorbate is a vital micronutrient required for many biological functions, including its action as a vital cofactor for Cu- and Fe-containing enzymes. As enzyme cofactor for HIF-hydroxylases, it is important for the regulation of hypoxia-inducible factor-1 (HIF-1), which governs cancer growth and spread. A lack of ascorbate increases both the level and activity of HIF-1 in cell culture.

This study aimed to restore ascorbate synthesis to human cells and to determine the effect of intracellular ascorbate biosynthesis on HIF-1 levels. HepG2 cells were gene modified using Lipofectamine LTX with a plasmid encoding the mouse Gulo cDNA and a control plasmid encoding the green fluorescent protein (GFP). Modified HepG2 cells were tested for genomic incorporation by PCR, for Gulo enzyme production by Western blotting, and ascorbate synthesis by high performance liquid chromatography with electrochemical detection (HPLC-ECD). Protein levels of HIF-1alpha in hypoxic cells were measured by Western blot analysis.

Parental HepG2 cells accumulated a mean of 120 nmol ascorbate per 1 million cells when loaded for 24h with 0.5 mM ascorbate. Gene-modified HepG2Gulo cells demonstrated a change in morphology and an increase in adherence, compared to HepG2GFP and parental HepG2 cells. A PCR-positive stable clone was able to synthesise ascorbate but only when the Gulo substrate, L-gulono-1,4-lactone, was supplied. Intracellular ascorbate levels then reached 5% of saturation levels. Hypoxic HIF-1 accumulation was reduced by addition of gulonolactone to this clone. However, gulonolactone also reduced HIF-1 levels in parental HepG2 cells, suggesting that it may similarly act as cofactor for the HIF-hydroxlases.

This study indicated that the ascorbate biosynthesis pathway in human cells is significantly modified and may contain numerous non-functional members besides gulono-lactone oxidase. Future biochemical studies will determine which other enzymes are non-functional.

Citation Format: Teresa Flett, Elizabeth Campbell, Elisabeth Phillips, Margreet CM Vissers, Gabi U. Dachs. Does gene transfer of gulono-lactone oxidase into human hepatocellular carcinoma cells restore ascorbate biosynthesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 727. doi:10.1158/1538-7445.AM2014-727
Abstract 742: Antitumor activity of Trametinib, a MEK1/2 inhibitor, in malignant pleural mesothelioma cells in vitro
Authors: Cho Hiroyuki , Matsumoto Seiji , Fujita Yoshiko , Kuroda Ayumi , Hashimoto Masaki , Takuwa Teruhisa , Menju Toshi , Sonobe Makoto , Kondo Nobuyuki , Date Hiroshi , Hasegawa Seiki
Published: May 2015

Introducion: Malignant pleural mesothelioma (MPM) is a highly aggressive malignancy and there is no approved targeted therapy. The MAPK pathway plays critical roles in the regulation of cell proliferation, growth, differentiation, and survival in multiple solid tumors, including MPM. Trametinib, a selective MEK inhibitor, have a survival benefit in patients with V600 BRAF-mutant metastatic melanoma. FDA approved Trametinib for these patients in May 2013. The effect of Trametinib in MPM cells has not been well studied.

Purpose: We examined the effects of Trametinib in MPM cells in vitro.

Methods: To examine the effect of Trametinib on the proliferation of MPM cells, we performed cell proliferation assay using four MPM cell lines, NCI-H2452, NCI-H226, NCI-H2052 and MSTO-211H. To examine the effect of Trametinib on intracellular signaling, we performed Western blot analysis in NCI-H226 cell line.

Results: Trametinib exhibited potent antiproliferative activity in all four MPM cell lines with IC50 values ranging from 0.5 μM to 44 μM. Trametinib blocked the phosphorylation of ERK until 72 hours and decreased the expression of CD44 in a dose-dependent manner. In addition, the expression of CD44 was inhibited (48-72 hours) after the suppression of ERK phosphorylation by Trametinib.

Conclusions: Our results suggest that Trametinib is a promising therapeutic agent for MPM.

Citation Format: Hiroyuki Cho, Seiji Matsumoto, Yoshiko Fujita, Ayumi Kuroda, Masaki Hashimoto, Teruhisa Takuwa, Toshi Menju, Makoto Sonobe, Nobuyuki Kondo, Hiroshi Date, Seiki Hasegawa. Antitumor activity of Trametinib, a MEK1/2 inhibitor, in malignant pleural mesothelioma cells in vitro. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 742. doi:10.1158/1538-7445.AM2014-742
Abstract 745: A non-redox reactive allosteric inhibitor of MAPK phosphatases with selective toxicity to human cancer cells
Authors: Vollmer Laura , Vernetti Lawrence , Bakan Ahmet , Korotchenko Vasiliy , Bahar Ivet , Day Billy , Tsang Michael , Vogt Andreas
Published: May 2015

Mitogen-activated protein kinase phosphatases (MKPs) are members of a family of dual specificity phosphatases (DUSPs) that regulate cellular signaling homeostasis by dephosphorylating mitogen-activated kinases, key mediators of cell death and survival. The archetype MKP, DUSP1 (also termed MKP-1/CL100), is overexpressed in ovarian, breast, and prostate cancers and found elevated in the “oncogenic signature” of RAS mutant tumor cells. DUSP1 mediates cancer cell migration and invasion, and protects cells from apoptosis by clinically used antineoplastic agents and gamma-irradiation. Despite the evidence that DUSP1 is a promising anticancer target, efforts to discover small molecule inhibitors have been largely unsuccessful. The MKP active site is shallow and contains a catalytic cysteine that is sensitive to oxidation. Hence, prior discovery screens have mostly identified redox-reactive structures with promiscuous biological activities. Using a zebrafish chemical screen, we recently discovered a new DUSP inhibitory chemotype that has no redox-reactive structural features and that is thought to bind to an allosteric site adjacent to the catalytic cavity. Structure-activity relationship studies in transgenic zebrafish identified an analog (VNK-215) that retained DUSP1 and DUSP6 inhibitory activity but was well tolerated by the developing embryo. Here we hypothesized that VNK-215 could be selectively cytotoxic to cancer cells due to its ability to inhibit DUSP1 and lack of redox-reactive features. We found that in MDA-MB-231 human breast cancer cells, VNK-215 had apoptotic and antimigratory activity at concentrations that inhibited DUSP1 in mammalian cells, and induced phosphorylation of the DUSP1 substrates ERK, p38, and JNK. Studies in primary rat hepatocytes and live zebrafish embryos revealed that VNK-215, unlike previously described DUSP inhibitors, did not induce reactive oxygen species, mitochondrial damage, or toxicity. Our data suggest that the promiscuous activities of existing DUSP inhibitors are the cause of redox reactivity rather than target inhibition, and posit that DUSP1 is a druggable anticancer target for small molecule allosteric inhibitors.

Citation Format: Laura Vollmer, Lawrence Vernetti, Ahmet Bakan, Vasiliy Korotchenko, Ivet Bahar, Billy Day, Michael Tsang, Andreas Vogt. A non-redox reactive allosteric inhibitor of MAPK phosphatases with selective toxicity to human cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 745. doi:10.1158/1538-7445.AM2014-745
Abstract 755: Repression of tumor survival pathways by novel and selective inhibitors of MNK1 and MNK2 kinases in glioblastoma and colorectal cancer
Authors: Rzymski Tomasz , Szajewska-Skuta Malgorzata , Zarebski Adrian , Sitarz Kamil , Sapala Lukasz , Zurawska Malgorzata , Salwinska Magdalena , Windak Renata , Trebacz Ewa , Daniel-Wojcik Joanna , Obuchowicz Radoslaw , Winnik Bozena , Wincza Ewelina , Kulesza Urszula , Kucwaj-Borysz Katarzyna , Milik Mariusz , Dreas Agnieszka , Brzozka Krzysztof
Published: May 2015

Herewith, we report development of small molecule inhibitors of MNK1 and MNK2 kinases and their cellular activity. MNK1 and 2 are MAP kinase-interacting kinases that are activated by RAS and MAPK signaling pathways and are involved in regulation of translation. Both kinases phosphorylate translation initiation factor eIF4e on a conserved serine 209 residue. eIF4E can contribute to the oncogenic transformation both in vitro and in vivo and is highly expressed in various tumor types. Interestingly, mice that lack both MNK1 and MNK2 do not have any apparent phenotype, which is promising for the therapeutic window of MNK1/2 inhibitors. SEL201 is a series of small molecule inhibitors which inhibit activity of both MNK1 and MNK2 in a low nM range. Selected compounds were tested on the kinome panels and indicated MNK1 and MNK2 as primary kinase targets. SEL201 compounds caused dose dependent inhibition of phosphorylation of eIF4e at Ser209 in various cancer cell lines at concentrations <100nM, which were lower when compared with other reported MNK1/2 inhibitors such as Cercosporamid and CGP57380. Consistently, potent inhibition of eIF4e Ser209 was observed also in vivo after oral administration of the inhibitors in xenograft models. High potency, selectivity and favorable ADME/PK profile indicates that SEL201 inhibitors would be useful tools in probing molecular consequences of eIF4e Ser209 inhibition in cancer cells alone and in combination with other inhibitors targeting PI3K/mTOR or RAS/MEK pathway. SEL201 in vitro and in vivo activities on viability and metastasis will be presented in cellular and in vivo models of colorectal cancer and glioblastoma. SEL201 series is further developed as a promising anticancer therapy with potentially wide therapeutic window.

Citation Format: Tomasz Rzymski, Malgorzata Szajewska-Skuta, Adrian Zarebski, Kamil Sitarz, Lukasz Sapala, Malgorzata Zurawska, Magdalena Salwinska, Renata Windak, Ewa Trebacz, Joanna Daniel-Wojcik, Radoslaw Obuchowicz, Bozena Winnik, Ewelina Wincza, Urszula Kulesza, Katarzyna Kucwaj-Borysz, Mariusz Milik, Agnieszka Dreas, Krzysztof Brzozka. Repression of tumor survival pathways by novel and selective inhibitors of MNK1 and MNK2 kinases in glioblastoma and colorectal cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 755. doi:10.1158/1538-7445.AM2014-755