bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract A12: Small molecule inhibitor of BCL2 in combination with RCHOP is effective in CD20 negative DLBCL.
Authors: Dutta Chaitali , Mayo Michele , Collins Mike , Brueckner Christopher , Lawson Deborah , Lai Zhongwu , Bao Larry , Reimer Corinne
Published: August 2014

Rituximab alone or in combination with chemotherapeutics is the first-line therapy for diffuse large B cell lymphomas (DLBCL). Although the complete response rate is quite impressive, vast majority of patient presents recurrent disease. The association between CD20 expression and clinical outcome in patients strongly suggests that reduced CD20 expression leads to inferior response to RCHOP (rituximab, cyclophosphamide, vincristine, doxorubicin and prednisone). In order to understand how loss of CD20 leads to development of RCHOP resistance, we developed rituximab resistant DoHH2 model in vivo by chronic exposure to rituximab. Characterization of several resistant in vivo xenografts revealed one model that maintained resistance to an acute dose of rituximab and demonstrated loss of CD20. Further characterization of the model demonstrated a loss of CD20 is associated with over expression of BCL2 and BIM. In vivo efficacy studies showed resistant line is insensitive to acute dose of RCHOP and treatment with an inhibitor of BCL2 (ABT199) in combination with chemotherapy resulted in better efficacy than RCHOP alone. We have identified an in vivo model of DLBCL where loss of CD20 and over expression of anti-apoptotic protein BCL2 leads to RCHOP resistance. These data suggest the addition of BCL2 inhibitor to chemotherapy might be effective in treating CD20 negative lymphomas.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A12.

Citation Format: Chaitali Dutta, Michele Mayo, Mike Collins, Christopher Brueckner, Deborah Lawson, Zhongwu Lai, Larry Bao, Corinne Reimer. Small molecule inhibitor of BCL2 in combination with RCHOP is effective in CD20 negative DLBCL. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A12.
Abstract A123: Structure-function studies and drug design on the histone lysine methyl methyltransferases NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1.
Authors: Di Luccio Eric , Morishita Masayo , Mevius Damiaan , Chen Yunpeng
Published: August 2014

Chromatin remodelers that include histone methyl transferases (HMTases) are becoming a focal point in cancer drug development. The NSD family of three HMTases, NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L are bona fide oncogenes found aberrantly expressed in several cancers, suggesting their potential role for novel therapeutic strategies.

Several histone modifiers including HMTase have clear roles in human carcinogenesis but the extent of their functions and regulations are not well understood, especially in pathological conditions. The extents of the NSDs biological roles in normal and pathological conditions remain unclear. In particular, the substrate specificity of the NSDs remains unsettled and discrepant data has been reported. NSD2/MMSET is a focal point for therapeutic interventions against multiple myeloma and especially for t(4;14) myeloma, which is associated with a significantly worse prognosis than other biological subgroups. Multiple myeloma is the second most common hematological malignancy in the United States, after non-Hodgkin lymphoma. Herein, we investigated the in vitro mechanisms of histone mark recognition and modifications by the SET domain of the NSDs and identify novel HMTase inhibitors by virtual ligand screening that may pave the way to specific NSD2/MMSET inhibitors suitable for therapeutic efforts against malignancies that include multiple myeloma.

Our data highlights the versatility of NSD1, NSD2, and NSD3 in recognizing and methylating lysine marks on H3 and H4. We report for the discovery of LEM-07 an inhibitor of NSD2/MMSET with an IC50 of 11.2 μM against H3K36 methylation in vitro. LEM-07 would be useful to explore the biology of NSD2.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A123.

Citation Format: Eric Di Luccio, Masayo Morishita, Damiaan Mevius, Yunpeng Chen. Structure-function studies and drug design on the histone lysine methyl methyltransferases NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A123.
Abstract A132: Development of a small-molecule inhibitor targeting the Wnt signaling pathway.
Authors: Yamada Tesshi , Masuda Mari , Sawa Masaaki
Published: August 2014

Wnt signaling is a major force driving colorectal carcinogenesis, but only a small number of druggable target molecules in the Wnt pathway have been found. Our recent series of proteomic studies has revealed that various classes of nuclear proteins participate in the β-catenin and T-cell factor-4 (TCF-4) complex and modulate the activity of Wnt signalling. Those included fusion/translocated in liposarcoma (FUS/TLS) (1), poly(ADP-ribose) polymerase-1 (PARP-1) (2), Ku70/Ku80 (3), DNA topoisomerase IIα (Topo IIα) (4), splicing factor-1 (SF1) (5), Ran (ras-related nuclear protein), RanBP2 (Ran binding protein-2), and RanGAP1 (Ran GTPase-activating protein-1) (6), Traf2- and Nck-interacting kinase (TNIK) (7). Among these proteins, TNIK protein kinase attracted our current interest because various small-molecule kinase inhibitors have been applied successfully to cancer treatment. TNIK was an activating kinase for TCF-4, and colorectal cancer cells are highly dependent upon the expression and catalytic activity of TNIK for proliferation (7). High-throughput screening of a kinase-focused compound library (>10,000 compounds) against recombinant TNIK identified a lead candidate that inhibited the kinase activity of TNIK with an IC50 value of 8.6 nM and the transcriptional activity of TCF-4. TNIK is a feasible drug target in the Wnt signaling pathway.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A132.

Citation Format: Tesshi Yamada, Mari Masuda, Masaaki Sawa. Development of a small-molecule inhibitor targeting the Wnt signaling pathway. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A132.
Abstract A135: Concurrent MCL1 and JUN amplification in pseudomyxoma peritonei.
Authors: Mansfield Aaron S. , Sio Terence , Grotz Travis E. , Graham Rondell P. , Molina Julian R. , Que Florencia G. , Miller Robert C.
Published: August 2014

Background: Pseudomyxoma peritonei (PMP) is a rare abdominal malignancy. We hypothesized that next generation exomic sequencing would identify recurrent mutations that may have prognostic or therapeutic implications.

Methods and Materials: Ten patients were selected based on availability of tissue and adequate follow-up. Mutations were tested for in 236 cancer-related genes in formalin-fixed paraffin-embedded (FFPE) slides using next-generation exomic sequencing (Foundation Medicine, Cambridge, MA). Immunohistochemistry (IHC) was used to detect MCL1 expression.

Results: Detectable mutations were found in 80% of patients. Seventy percent harbored a KRAS mutation, most commonly involving codon 12 (G12D in four cases, and one case each of G12V, G12A and A59T). Four GNAS mutations (R201H/R201C substitutions) were also detected. MCL1 and JUN were concurrently amplified in three patients. One patient with MCL1 and JUN amplification had concurrent amplification of MYC and NFKBIA. ZNF703 was amplified in one patient. Patients with MCL1 amplification were also found to express MCL1 by IHC, but MCL1 expression was also detected in some patients without amplification.

Conclusions: We are first to report MCL1 and JUN co-amplification in PMP. Expression of MCL1 may not be completely dependent upon amplification. The prognostic and therapeutic implications of these recurrent mutational events are the subject of ongoing investigation.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A135.

Citation Format: Aaron S. Mansfield, Terence Sio, Travis E. Grotz, Rondell P. Graham, Julian R. Molina, Florencia G. Que, Robert C. Miller. Concurrent MCL1 and JUN amplification in pseudomyxoma peritonei. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A135.
Abstract A138: Identification of PKM2 as a potential biomarker of high-grade ovarian serous tumor.
Authors: Poersch Aline , Souza Lucas Oliveira , Faça Vitor Marcel , Greene Lewis Joel , Candido dos Reis Francisco Jose
Published: August 2014

The M2 splice isoform of pyruvate kinase (PKM2), that catalyzes the later step of glycolysis, is a key regulator of aerobic glycolysis (Warburg effect) in cancer cells. Expression and low enzymatic activity of PKM2 confer on cancer cells the glycolytic phenotype, which promotes rapid energy production and flow of glycolytic intermediates into collateral pathways to synthesize nucleic acids, amino acids, and lipids without the accumulation of reactive oxygen species [1]. Furthermore, studies indicate that the PKM2 expression might be an early event in carcinogenesis [2]. Thus, PKM2 can be a useful biomarker for the early detection of tumors. Although the presence of PKM2 is described for different types of cancer, there is no information specific PKM2 in ovarian cancer. Thus, to investigate the presence of PKM2 in ovarian cancer, we performed proteomic analysis in a pool of ovarian serous adenocarcinoma (malignant) fluids (n=10) and in a pool of ovarian serous cystadenoma (benign) fluids (n=10) using immunodepletion of albumin and IgG, isotopic labeling with acrylamide, separation by SDS-PAGE, in situ digestion with trypsin and liquid chromatography ion exchange followed by reverse phase coupled to a mass spectrometer LTQ-ORBITRAP (LC-MS/MS). Moreover, evaluated the expression of PKM2 in plasma and tumor fluid of ovarian serous adenocarcinoma (n=14) and of ovarian serous cystadenoma (n=13) using the kit ELISA EDTA-Plasma Test (ScheBo® Biotech AG), and evaluated the expression of PKM2 in tissue microarrays of 71 ovarian serous adenocarcinoma samples (different stages and grades) using Tumor M2-PK Antibodies (monoclonal, ScheBo®, Biotech AG). The PKM2 protein was detected in proteomic analysis of ovarian serous adenocarcinoma. In ELISA test, PKM2 can be confirmed in both plasma and tumor fluid of ovarian serous adenocarcinoma and ovarian serous cystadenoma, with significant difference between fluids (p<0.0001). Concentrations of PKM2 in plasma and tumor fluid are higher in ovarian serous adenocarcinoma. The tissue microarrays analysis confirmed that PKM2 is highly expressed in adenocarcinoma of all stages and grades. The presence of PKM2 in different biological samples of ovarian cancer and in all stages and grades suggests that your inhibition is a viable strategy in the treatment of this malignancy and conducting research in tumor metabolism will benefit cancer treatment.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A138.

Citation Format: Aline Poersch, Lucas Oliveira Souza, Vitor Marcel Faça, Lewis Joel Greene, Francisco Jose Candido dos Reis. Identification of PKM2 as a potential biomarker of high-grade ovarian serous tumor. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A138.
Abstract A150: A methodology for the isolation, culture, and immortalization of human breast epithelial and myoepithelial cells.
Authors: Fuster Gemma , Zubeldia-Plazaola Arantzazu , Mancino Mario , Fernández-Nogueira Patricia , Ametller Elisabet , Gascón Pedro , Almendro Vanessa
Published: August 2014

Introduction: Breast tissue is composed by different cell types including epithelial and myoepithelial cells, macrophages, fibroblasts, adipocytes, and cells from the immune system. Two main lineages, epithelial and myoepithelial cells, are the most essential cell populations in the normal mammary gland and also in breast cancer. Traditionally, cancer research has been performed using commercial cell lines, but primary cell cultures suppose a powerful tool to study with a higher reliability new aspects of mammary gland biology including normal and diseased tissue. However, normal primary human epithelial cells in culture achieve senescence at 10 to 40 population doubling, hampering their long-term culture. In addition, some studies have described lineage-specific marker limitations to be used in order to isolate these two cell types, since some of the markers tend to change during cell culture.

Experimental Procedures: In this protocol we compared two different methodologies in an effort to improve isolation, culture and immortalization of different cell populations of human normal mammary epithelium. We based our approaches in previously described methods incorporating additional steps to improve cell survival, to preserve cellular antigens used for isolation and validation of cell subpopulations and to enhance cellular transformation. For these purposes, we determined cell growth and viability, and also cell-lineage specific markers of cytospinned cells in both methodologies used.

Results: One of the goals of the present work to yield on cell survival and antigens preservation is in fact overnight digestion at low enzymatic concentration. Other crucial steps are cell immortalization and also addition of critical compounds to the cell culture media.

Conclusions: In the present work, we propose some guidelines to establish more efficiently mammary epithelial cell lines allowing long-term cell culture system and providing us a strong instrument to better understand the role of the different epithelial cell types and the origins of breast cancer.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A150.

Citation Format: Gemma Fuster, Arantzazu Zubeldia-Plazaola, Mario Mancino, Patricia Fernández-Nogueira, Elisabet Ametller, Pedro Gascón, Vanessa Almendro. A methodology for the isolation, culture, and immortalization of human breast epithelial and myoepithelial cells. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A150.
Abstract A156: CrkI and CrkII adaptor proteins promote invasiveness and metastasis via epithelial-mesenchymal transition (EMT) in A549 lung adenocarcinoma cells.
Authors: Elmansuri Aiman , Tanino Mishie , Mahabir Roshan , Wang Lei , Tsuda Masumi , Kimura Taichi , Nishihara Hiroshi , Tanaka Shinya
Published: August 2014

Epithelial-to-mesenchymal transition (EMT) is a leading phenomenon implicated in morphogenesis, invasiveness and metastasis of cancer cells. Likewise, Crk adaptor proteins described to promote an epithelial-mesenchymal-like transition and are required for HGF-mediated cell spreading and breakdown of epithelial adherens junctions in MDCK kidney epithelial cells. In this study we show that overexpression of CrkI and CrkII; members of Crk adaptor family of signalling proteins in A549 lung adenocarcinoma cells induce morphological changes resemble mesenchymal cells with high motility and invasiveness potential in both in vitro and in vivo. Furthermore, CrkI and CrkII both induce EMT but mostly through different pathways, while CrkI had a significant effect on TGFβ1-SMAD pathway which might be the inducer of EMT, more than CrkII, CrkII which had a higher Rac1 activity in the other hand showed a prominent effect on the expression of transcriptional factors regulating EMT like Snail and Slug, leading to almost total loss of the cell-cell adhesion glycoprotein E-cadherin expression, as well as remarkable increases in the production of extracellular matrix metalloproteinase (MMP) 2. These effects were opposed by inhibiting Rac1 activity. In conclusion, we could describe that CrkI and CrkII have a differential effect on the EMT process via activating Rac1, MMPs production, and the potential effect on TGF-β signalling, highlighting novel regulatory mechanisms of the adaptor protein Crk, and its involvement in cancer metastasis.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A156.

Citation Format: Aiman Elmansuri, Mishie Tanino, Roshan Mahabir, Lei Wang, Masumi Tsuda, Taichi Kimura, Hiroshi Nishihara, Shinya Tanaka. CrkI and CrkII adaptor proteins promote invasiveness and metastasis via epithelial-mesenchymal transition (EMT) in A549 lung adenocarcinoma cells. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A156.
Abstract A158: DAXX/ATRX and MEN1 genes are stong prognostic markers in pancreatic neuroendocrine tumor.
Authors: Park Joo Kyung , Paik Woo Hyun , Ryu Ji Kon , Kim Yong-Tae , Lee Se-Hoon
Published: August 2014

Introduction: The incidence and prevalence of pancreatic neuroendocrine tumors (PNET) are increasing; these tumors represent approximately 1.3% of all cases of pancreatic cancer in incidence and 10% of cases in prevalence. PNET has usually better prognosis compared to that of pancreatic ductal adenocarcinoma, however, some of PNETs are diagnosed as in advanced stage with distant metastasis. Accurate prediction of its prognosis and the proper treatment may be very important in patients with PNETs.

Aims and Methods: The aim of this study was to explore prognostic markers based on genetic basis of PNETs and they were known as the most frequently mutated genes MEN1, DAXX/ATRX. The pathologically confirmed 111 patients with PNETs were enrolled and the following clinical and pathologic factors were evaluated; AJCC stage, treatment modalities, differentiation and mitosis. Also, immunohistochemical staining of MEN1, DAXX/ATRX genes, Ki-57, chromogranin, synaptophysin, CD56, somatostatin, insulin and glucagon were done.

Results: The median age of study patients was 55 yrs and AJCC staging of the patients were as follows:IA;41 patients, IB;30 patients, IIA;13 patients, IIB;8 patients, IV; 19 patients. The median OS was 55.5 months and 81 patients underwent R0 resection. There were 23 patients (27%), 17 patients (20%) and 27 patients (31%) were positive for MENIN, ATRX and DAXX respectively. In addition, DAXX and ATRX are known to be mutually exclusive genes. Mutations in the MEN1 and DAXX/ATRX genes were resulted in negative immunohistochemical staining and it was significantly associated with longer DFS and OS (33 mo. vs. 65 mo., p < 0.01; 63 mo. vs. 124 mo., p <0.001 respectively). AJCC staging and grade of differentiation were the statistically significant prognostic factors among other clinical variables.

Conclusion: Mutations in the MEN1 and DAXX/ATRX genes (negative immunohistochemical staining results) were associated with better clinical prognosis. This study was the first one to investigate prognostic markers based on genetic basis of PNETs.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A158.

Citation Format: Joo Kyung Park, Woo Hyun Paik, Ji Kon Ryu, Yong-Tae Kim, Se-Hoon Lee. DAXX/ATRX and MEN1 genes are stong prognostic markers in pancreatic neuroendocrine tumor. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A158.
Abstract A16: A drug combination screen identifies taxanes as synergistic agents with the oral IAP inhibitor Debio 1143 in non-small cell lung cancer cells.
Authors: Langdon Casey G. , Wiedemann Norbert , Held Mathew A. , Platt James T. , Lévy Frédéric , Zanna Claudio , Vuagniaux Grégoire , Sorensen Mel , Wang Shaomeng , Bosenberg Marcus W. , Stern David F.
Published: August 2014

Background: Drug resistance is a major problem in cancer therapy. The combination of drugs targeting simultaneously multiple critical nodes of the signalling networks controlling growth and survival of cancer cells is necessary to achieve long-lasting responses. The members of the Inhibitor of apoptosis protein (IAP) family are key negative regulators of programmed cell death. Their frequent overexpression in most cancer types contributes to tumor cell survival and resistance to cancer therapy making IAPs attractive therapeutic targets. The oral monovalent SMAC mimetic, Debio 1143/AT-406, functions as an antagonist of multiple IAP proteins (cIAP1/2 and XIAP) and is currently in clinical development for cancer treatment. The goal of this study is to identify novel synergistic combination partners with Debio 1143 in non-small cell lung cancer (NSCLC).

Material and Methods: An in vitro high-throughput combination screen was performed using 6 human NSCLC cell lines bearing various genetic alterations. Debio 1143 was pairwise combined with 128 commercially available oncology compounds in a cell viability assay. To identify supra-additive drug combinations, the dose-response curves were analysed using the Bliss independence method. Synergistic combinations were further studied using tumor xenograft mouse models.

Results: Among several interesting combinations, we observed strong synergism of Debio 1143 combined with docetaxel or paclitaxel, two standard-of-care drugs in NSCLC. The beneficial effect of the combination between Debio 1143 and taxanes was further validated in multiple mouse cancer xenografts where the combination caused marked anti-tumour activity that was superior to either monotherapy.

Conclusion: These findings underline the feasibility of using in vitro high-throughput screening for the discovery of novel drug combinations with increased anti-tumour efficacy in vivo. Furthermore, they provide a rationale for the combination of the SMAC mimetic Debio 1143 with taxanes and are the basis for ongoing clinical trials in several cancer types.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A16.

Citation Format: Casey G. Langdon, Norbert Wiedemann, Mathew A. Held, James T. Platt, Frédéric Lévy, Claudio Zanna, Grégoire Vuagniaux, Mel Sorensen, Shaomeng Wang, Marcus W. Bosenberg, David F. Stern. A drug combination screen identifies taxanes as synergistic agents with the oral IAP inhibitor Debio 1143 in non-small cell lung cancer cells. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A16.
Abstract A160: Characterization of novel regulators for epithelial-mesenchymal transition.
Authors: Li Linna , Lu Emily , Chang Jeffrey , Li Wenliang
Published: August 2014

The epithelial-mesenchymal transition (EMT) confers mesenchymal properties on epithelial cells and has been closely associated with the acquisition of aggressive traits of breast cancer cells. Recently, a few kinases, such as FYN and c-Met, were reported to participate in regulating EMT. However, the roles of the majority of >700 human kinases in EMT and breast cancer progression are still unknown. Here we carried out human kinase cDNA screens to identify novel regulators of EMT. Many unknown EMT regulators and a few known ones such as PI3K, PDGFRA, FYN and c-Met, were found to up-regulate mesenchymal marker vimentin. Some also increase expression of fibronectin and N-cadherin, as well as EMT transcriptional regulators, such as ZEB1/2, Snail and Slug. At the same time, the cells acquired mesenchymal phenotypes, such as increased migration/invasion activity, enhanced capability to survive and proliferate in growth factor deprivation condition or under drug treatments. Interestingly, FACS analysis also showed a substantial increase in CD44hiCD24low population in kinase-transducted mammary gland epithelial cells. The increase of CD44hi population could be attributed to increase of a CD44 mesenchymal variant - the standard form CD44s and decrease of the epithelial variant CD44 v8-10. And this alternation was associated with down-regulation of ESRP1 and ESRP2, two splicing factors that regulate CD44 splicing and EMT. Furthermore, the mammary gland epithelial cells undergoing EMT showed increase capability of forming mammosphere and differentiating into other lineages, such as osteoblast and adipocyte. Importantly, some of these novel EMT regulators are associated with TNBC, stemness and poor prognostics of human breast cancers. One novel regulator, a poorly studied serine/threonine protein kinase, was tested in vivo and found to be capable of generating primary tumor and metastasis at much higher efficiency. Further study of these novel EMT regulators promises to provide new mechanisms of breast cancer progression, and may also lead to development of new prognostic markers and therapeutics.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A160.

Citation Format: Linna Li, Emily Lu, Jeffrey Chang, Wenliang Li. Characterization of novel regulators for epithelial-mesenchymal transition. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A160.
Abstract A163: A diverse array of mutations in MTOR are hyperactivating and correlate with rapamycin sensitivity.
Authors: Grabiner Brian , Sabatini David
Published: August 2014

Components of the PI3K-Akt-mTOR signaling axis are frequently mutated in cancer but relatively few mutations have been observed in the MTOR gene itself, which encodes the mTOR kinase. We used cancer genome sequencing data to generate a catalogue of over 450 MTOR point mutations found in cancer and from these identified a set of over 25 that cause mTOR pathway hyperactivation in cells. Mutations occur in multiple cancer types and cluster in several distinct regions in the C-terminal half of mTOR. The distribution and diversity of hyperactivating mutations is distinct from those found in kinases such as AKT1 or BRAF but similar to the pattern seen in PIK3CA. The mutations do not affect the sub-cellular localization of mTOR or its capacity to nucleate the mTORC1 and mTORC2 complexes, but the mutants do bind less DEPTOR, an mTOR inhibitor. In kinetic analyses, several of the most frequently recurrent mutations demonstrate increased K-cat over wild-type mTOR, suggesting that these mutations alter the mTOR kinase itself. Lastly, cancer cell lines with naturally arising mTOR mutations that fall within the clusters exhibited hypersensitivity to mTOR inhibitors. Thus, a diverse set of mutations in mTOR can activate the mTOR pathway and may predict which patients are most likely to respond to rapamycin-based therapies.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A163.

Citation Format: Brian Grabiner, David Sabatini. A diverse array of mutations in MTOR are hyperactivating and correlate with rapamycin sensitivity. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A163.
Abstract A166: A Phase I pharmacokinetic/pharmacodynamic (PK/PD) study of the sachet formulation of the oral dual PI3K-mTOR inhibitor BEZ235 given twice daily (BID) in patients (pts) with advanced solid tumors.
Authors: Bendell Johanna C. , Kurkjian Carla , Infante Jeffrey R. , Bauer Todd , Burris Howard A. , Spigel David R. , Yardley Denise A. , Greco F Anthony , Shih Kent C. , Thompson Dana S. , Jones Suzanne F.
Published: August 2014

Background: The PI3 kinase pathway is the most dysregulated pathway in cancers and is an attractive target for antitumor therapy. BEZ235 is a potent, highly specific and selective PI3K inhibitor that also binds to the catalytic site of mTOR, inhibiting mTORC1/2.

Methods: Pts were enrolled in a 3+3 dose escalation design to determine the maximum tolerated dose, toxicities, PK, and PD of BEZ235 when administered BID as an oral sachet formulation. For intrapatient PK comparison, pts received the total dose in a QD schedule for the first 8 days of the initial 28 day cycle. The QD lead-in was later eliminated. PK and PD assessments (PET scans, skin biopsies, and blood-based biomarkers) were collected and disease assessments were conducted every 2 cycles.

Results: 33 pts (median age 62, range 20-86 yrs; 17 male/16 female) received BEZ235 at the doses described below in the table. Two DLTs of gr 3 mucositis occurred early in the treatment cycle at 600 mg BID, so the lead-in QD dosing was eliminated. However, DLTs of fatigue and mucositis limited dosing at 600 mg BID in subsequent pts. The 400 mg BID dose level was re-explored, but dosing was again limited by DLTs and chronic low grade toxicities. Twelve pts were enrolled at an intermediate dose of 300 mg BID with no QD lead-in, and DLT (gr 3 mucositis) was reported in a single patient. Preliminary PK data demonstrate a consistent increase in PK parameters (Cmax and AUC) with dose level compared to QD dosing. PET scan evaluations demonstrate anti-PI3K activity via decreased SUV uptake at various doses, including the lowest dose. 15 pts experienced stable disease as their best response.

Conclusions: The recommended dose of BEZ235 administered twice daily as an oral sachet formulation is 300 mg BID. The toxicity profile for BID dosing is similar to that reported for other PI3K and mTOR inhibitors.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A166.

Citation Format: Johanna C. Bendell, Carla Kurkjian, Jeffrey R. Infante, Todd Bauer, Howard A. Burris, David R. Spigel, Denise A. Yardley, F Anthony Greco, Kent C. Shih, Dana S. Thompson, Suzanne F. Jones. A Phase I pharmacokinetic/pharmacodynamic (PK/PD) study of the sachet formulation of the oral dual PI3K-mTOR inhibitor BEZ235 given twice daily (BID) in patients (pts) with advanced solid tumors. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A166.
Abstract A168: Hepatitis B virus pre-S2 mutant stimulates aerobic glycolysis through mammalian target of rapamycin signaling in tumorigenesis.
Authors: Teng Chiao-Fang , Wu Han-Chieh , Hsieh Wen-Chuan , Tsai Hung-Wen , Su Ih-Jen
Published: August 2014

Hepatitis B virus (HBV) pre-S2 mutant identified in ground glass hepatocytes (GGHs) in patients with chronic HBV infection has been proposed as viral oncoprotein and can induce hepatocellular carcinoma (HCC). Previously, we observed the activation of mammalian target of rapamycin (mTOR) by HBV pre-S2 mutant in GGHs and HCCs. The frequent association of metabolic syndrome with HCC raises the possibility that pre-S2 mutant-induced mTOR activation plays a driving role in the development of metabolic disorders in HBV-related HCC patients. To address this issue, we developed transgenic mice harboring pre-S2 mutant and analyzed gene expression profiles of the transgenic livers. In support of our hypothesis, the pre-S2 mutant transgenic mice showed glycogen depletion and glycolysis elevation in HCCs, a phenotype that has been implicated in highly proliferative malignancy. We identified that pre-S2 mutant could initiate an mTOR-dependent glycolytic pathway, involving Yin Yang 1, c-Myc, and glucose transporter 1 to upregulate aerobic glycolysis. This mTOR-mediated signaling pathway was significantly activated in the pre-S2 mutant transgenic livers and HCCs and contributed to aberrant glucose uptake and lactate production in vitro. Furthermore, we demonstrated that pre-S2 mutant could promote proliferation and invasion of HCC cells by sustaining the aerobic glycolysis. Activation of this glycolysis-associated mTOR signaling cascade was also observed in human HBV-related HCCs. Collectively, our results support the role of mTOR activation in the metabolic reprogramming of hepatocytes in chronic HBV infection and tumorigenesis, which should be valuable for chemoprevention design for HCC.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A168.

Citation Format: Chiao-Fang Teng, Han-Chieh Wu, Wen-Chuan Hsieh, Hung-Wen Tsai, Ih-Jen Su. Hepatitis B virus pre-S2 mutant stimulates aerobic glycolysis through mammalian target of rapamycin signaling in tumorigenesis. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A168.
Abstract A19: Andrographolide analogue induces crosstalk between apoptosis and autophagy via inhibition of PI3K/Akt/mTOR pathway in human leukemic cells.
Authors: Kumar Deepak , Roy Rajneeta , Chowdhury Chinmay , Chatterjee Mitali , Das Padma
Published: August 2014

Current chemotherapeutic agents solely based on apoptosis induction have limited efficacy. Therefore, new therapeutic strategies and drugs still need to be explored. Various forms of programmed cell death are being increasingly implicated in anticancer therapy and the complex interplay among them is critical to the overall fate of cells. We elucidated the underlying mechanism of the most potent Andrographolide analogue (AG-4) mediated action that involved crosstalk between apoptosis and autophagy in human leukemic U937 cells. AG-4 induced cytotoxicity was associated with redox imbalance and apoptosis which involved mitochondrial depolarisation, altered apoptotic protein expressions, activation of the caspase cascade leading to cell cycle arrest. Incubation with caspase inhibitor Z-VAD-fmk or Bax siRNA decreased cytotoxic efficacy of AG-4 emphasising critical roles of caspase and Bax. In addition, AG-4 induced autophagy as evident from LC3-II accumulation, increased Atg protein expressions and autophagosome formation. Pre-treatment with 3-MA or Atg 5 siRNA suppressed the cytotoxic effect of AG-4 implying the pro-death role of autophagy. Furthermore, incubation with Z-VAD-fmk or Bax siRNA subdued AG-4 induced autophagy and pre-treatment with 3-MA or Atg 5 siRNA curbed AG-4 induced apoptosis - implying that apoptosis and autophagy act as partners in the context of AG-4 mediated action. AG-4 also inhibited PI3K/Akt/mTOR pathway. Inhibition of mTOR (by rapamycin or mTOR siRNA) or Akt (by LY294002 or Akt siRNA) augmented AG-4 induced apoptosis and autophagy signifying its role in apoptosis-autophagy crosstalk. Thus, these findings provide new perspective of AG-4 as potential molecule targeting programmed cell death for future cancer therapeutics.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A19.

Citation Format: Deepak Kumar, Rajneeta Roy, Chinmay Chowdhury, Mitali Chatterjee, Padma Das. Andrographolide analogue induces crosstalk between apoptosis and autophagy via inhibition of PI3K/Akt/mTOR pathway in human leukemic cells. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A19.
Abstract A195: The role of P2X7 receptor in glioma cells.
Authors: Tamajusuku Alessandra S. K , Kipper Franciele C. , Filippi-Chiela Eduardo C. , Flores Débora G. , Reder Gleice M. , Meurer Luise , Battastini Ana M.O. , Roesler Rafael , Lenz Guido , Wink Marcia R.
Published: August 2014

P2X7 is an ionotropic receptor, whose activation by extracellular ATP can cause pro- or anti-apoptotic responses, depending on the concentration of the ligand. This receptor is expressed in almost all the cell types of the central nervous system and has been linked to cell death in several cells. Gliomas are primary tumors that arise in the CNS, and glioblastoma is the most deadly brain tumor due to their high proliferation, migration and infiltrative nature. Here, we show that survival of patients with gliomas directly correlate with the expression of P2X7 purinergic receptor analyzed with immunohistochemistry of a local group of patients or microarray in a set of patients from “REMBRANDT” and “The Cancer Genome Atlas” databases. A sub-population of cells more sensitive to ATP expressed more P2X7 when compared to a less sensitive subpopulation. Accordingly, RNA interference of the P2X7 receptor drastically reduced ATP-induced cell death, decreased cell adhesion and promoted migration, suggesting that this receptor is necessary for this effect. Since these are features of more aggressive cancers, this could be part of the explanation for the correlation observed in the patients’ outcome. These data support the importance of the purinergic system in general and the P2X7 receptor particularly in the pathobiology of gliomas.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A195.

Citation Format: Alessandra S. K Tamajusuku, Franciele C. Kipper, Eduardo C. Filippi-Chiela, Débora G. Flores, Gleice M. Reder, Luise Meurer, Ana M.O. Battastini, Rafael Roesler, Guido Lenz, Marcia R. Wink. The role of P2X7 receptor in glioma cells. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A195.
Abstract A196: Downregulation of kynurenine 3-monooxygenase (KMO) function prohibits canine mammary gland tumor (cMGT) cells from going wild.
Authors: Liao Albert T. , Lin Chen-Si , Chang Mei-Hsien
Published: August 2014

Kynurenine 3-monooxygenase (KMO), mainly found on the outer membrane of the mitochondria, is one of the enzymes in the kynurenine pathway of tryptophan metabolism. KMO catalyzes L-kynurenine (KYN) to form 3-hydroxy kynurenine (3-HK) and further generates the downstream metabolite quinolinic acid (QA) which is an N-methyl-D-aspartate (NMDA) agonist. In the past, KMO was considered to be associated with neurodegenerative diseases because the downstream metabolites demonstrate excitotoxicity to CNS and act as factors in neurodegenerative diseases. In our previous study has shown that overexpression of KMO is related to tumor malignancy and survival time of cMGT-suffering dogs (in progress). In this study, we investigated function of KMO in cMGT cells. First of all, KMO expression of cMGT cells (CMT-1, MPG and CF41.mg) was identified in mRNA and protein level. Second, the application of KMO inhibitor reduced proliferation and migration of cMGT cells. The reduced proliferation, not migration, could be restored by NMDA or QA. Third, the application of KMO inhibitor also decreased the activity of Erk, Akt and STAT3 in cMGT cells. However, the decreased activity of Erk and STAT3 in cMGT cells could be restored through the application of NMDA of QA. Our data suggest that KMO is involved in the proliferation and migration of cMGT cells. Furthermore, the inhibition of proliferation by KMO inhibitor is mainly through Erk and STAT3 signaling cascades and the signaling pathway may be activated through the NMDA receptor. The inhibition of migration by KMO inhibitor is mainly through Akt signaling cascades. In conclusions, KMO might be a new therapeutic target of cMGT due to the downregulation of KMO reduces proliferation and migration of cMGT cells.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A196.

Citation Format: Albert T. Liao, Chen-Si Lin, Mei-Hsien Chang. Downregulation of kynurenine 3-monooxygenase (KMO) function prohibits canine mammary gland tumor (cMGT) cells from going wild. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A196.
Abstract A201: Development of new assay systems for screening inhibitory molecules of c-Myb.
Authors: Uttarkar Sagar R. , Goblirsch Michael , Jose Joachim , Klempnauer Karl-Heinz
Published: August 2014

c-myb is a proto-oncogene encoding a transcription factor which is highly expressed in hematopoietic progenitor cells. It is primarily involved in regulation of the expression of genes important for differentiation, cell proliferation and lineage determination. The c-Myb protein is an interesting therapeutic target because emerging evidence suggests that deregulated c-Myb expression is involved in several types of leukemia and development of human tumors such as breast and colon cancer, adenoid cystic carcinoma and subtypes of glioblastoma. So far therapeutic low molecular weight inhibitors for c-Myb have not been reported. Based on the fact that the ability of c-Myb to act as a transcription factor is highly dependent upon its interaction with the coactivator CBP/p300, we have developed novel in vivo and in vitro assays which allow screening of chemical inhibitors of Myb. The in vivo assay consists of the N- and C-terminal halves of firefly luciferase which are expressed as fusion proteins with either the KIX domain of p300 or the p300 binding region of c-Myb. KIX and c-Myb interaction leads to complementation of the luciferase molecule rendering it active, which can be monitored by a standard luciferase assay. The in vitro system employs a bacterial auto-display system. The KIX domain of p300 is expressed in E coli in such a way that it is displayed on the surface of the bacterial cells. Myb is expressed as a soluble GFP fusion protein which is added to the bacterial cells. The interaction between both binding partners renders the bacterial cells fluorescent which can be quantified by flow-cytometry. These assays should be useful to screen large libraries of compounds as they both allow high throughput techniques.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A201.

Citation Format: Sagar R. Uttarkar, Michael Goblirsch, Joachim Jose, Karl-Heinz Klempnauer. Development of new assay systems for screening inhibitory molecules of c-Myb. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A201.
Abstract A224: Autophagy and SQSTM1 on the RHOA(d) again.
Authors: Belaid Amine , Diogop N'diaye Papa , Cerezo Michaël , Brest Patrick , J. Klionsky Daniel , Carle Georges F , Hofman Paul , Mograbi Baharia
Published: August 2014

Degradation of signaling proteins is one of the most powerful tumor suppressive mechanisms by which a cell can control its own growth, its survival, and its motility. Emerging evidence suggests that autophagy limits several signaling pathways by degrading kinases, downstream components, and transcription factors; however, this often occurs under stressful conditions. We show here that the constitutive autophagy is required for fine-tuning the RHOA pathway. Specifically, inhibition of autophagosome degradation induces the accumulation of the GTP-bound form of RHOA. The active RHOA is sequestered via SQSTM1/p62 within autolysosomes, and accordingly fails to localize to the lamella of crawling cells, one region where RHOA inactivation is essential in cell migration. As a result, all autophagy compromises deregulate cell motility. We therefore propose the term “signalphagy” to indicate a dedicated type of macroautophagy that degrades and thereby maintains the appropriate level of active signaling proteins to achieve tumor suppression. In this model, the remarkable dynamics of autophagy together with its integration of extracellular cues might dictate the time and place where RHOA is active to ensure directed cell motility.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A224.

Citation Format: Amine Belaid, Papa Diogop N'diaye, Michaël Cerezo, Patrick Brest, Daniel J. Klionsky, Georges F Carle, Paul Hofman, Baharia Mograbi. Autophagy and SQSTM1 on the RHOA(d) again. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A224.
Abstract A23: Bioinformatic analysis of PTPRK reveals a potential link to STAT3 phosphorylation in HNSCC.
Authors: Pendleton Kelsey P. , Lui Vivian W. , Lu Yiling , Gilbert Breean R. , Levine Kevin , Mills Gordon B. , Grandis Jennifer R.
Published: August 2014

Purpose: The emerging role of various PTPRs (protein tyrosine phosphatase receptors) on signaling regulation prompted us to investigate the genomic alterations of members of the PTPR in HNSCC. PTPRK is a known tumor suppressor, and knockdown or mutation of PTPRK has been found to drive tumorigenesis in breast and colorectal cancer. The role of PTPRK in HNSCC is largely unknown. Recent genomic studies in HNSCC revealed that PTPRK is mutated in HNSCC. Here, we further investigated the genomic aberrations of PTPRK, in primary HNSCC tumors and examined if any of these genomic aberrations are associated with key phosphorylation changes in signaling proteins in HNSCC tumors.

Experimental Design: Data-mining of the HNSCC genomic and protein array data was performed using the cBio portal (http://www.cbioportal.org/public-portal/). A total of 306 HNSCC primary tumors were analyzed in the genomic analysis, while proteomic data were available for a subset of these tumors (total of 200). We analyzed for genomic events, including PTPRK amplification, gain of copy number, and increased in mRNA expression (> 1 SD above the mean). The levels of phosphorylated signaling proteins of 150 proteins were compared between the PTPRK-altered group vs. the PTPRK-unaltered group. Preliminary validation on signaling changes were performed.

Results: Bioinformatic analysis of the cBio data showed that PTPRK is mutated in 1% (2/200 cases), amplified in 0.5% (1/200 cases), with copy gain in 12% (24/200 cases), and increased mRNA expression in 13.5% (27/200 cases). There are no tumors with PTPRK deletion. These results implicate a gain of function of PTPRK in HNSCC. Unexpected proteomic findings revealed that increased phosphorylation of STAT3 (p = 0.005), ERBB2 (p = 0.018), and EGFR (p = 0.031) proteins were found to be associated with tumors with the genomic signature of “PTPRK-mutated/amplified/gain/increased in mRNA expression” vs. the PTPRK-unaltered tumors. Preliminary validation of the proteomic findings indicate that increased expression of PTPRK (by transient transfection into HNSCC cells) did result in increased pSTAT3 expression (34% increase vs. vector control).

Discussion: This study used both bioinformatics and cellular assays to demonstrate PTPRK associated with enhanced pSTAT3. Future studies are required to elucidate the role of PTPRK, likely indirect, on STAT3 regulation.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A23.

Citation Format: Kelsey P. Pendleton, Vivian W. Lui, Yiling Lu, Breean R. Gilbert, Kevin Levine, Gordon B. Mills, Jennifer R. Grandis. Bioinformatic analysis of PTPRK reveals a potential link to STAT3 phosphorylation in HNSCC. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A23.