bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2927: Targeting p53 with Bak and Bax mitochondrial targeting signals for the treatment of ovarian cancer
Authors: Lu Phong 
Published: August 2015

Abstract
Although the main function of p53 is a nuclear transcription factor that has important roles in cell cycle arrest, DNA repair, and apoptosis, p53 can directly trigger the intrinsic apoptotic pathway through the mitochondria. p53 has been known to bind to mitochondrial anti-apoptotic proteins (Bcl-2 and Bcl-XL) and pro-apoptotic proteins (Bak and Bax), which will cause the oligomerization of Bak and Bax. The result is the formation of permeable pores on the mitochondrial outer membrane, which in turn cause the release of cytochrome c and activation of caspase-3. Targeting p53 to the mitochondria is an attractive approach because it can cause a rapid apoptotic response. We have introduced the mitochondrial targeting signal (MTS) from Bak or Bax to the C-terminus of p53 and have shown the superior efficacy of p53-BakMTS and p53-BaxMTS over wtp53 in many human cancer cell lines. We have identified that the DNA binding domain (DBD) of p53 may be the minimal domain of p53 required for apoptosis. Our preliminary data in SKOV-3 ovarian cancer cells also suggests that DBD-BakMTS may work just as well as full length p53-BakMTS. Further in humans, the single nucleotide polymorphism at codon 72 from Pro to Arg is known to enhance the mitochondrial targeting of p53. We have recently made the P72R mutation in our p53 constructs. Our goal is to use a novel version of p53 directed to the mitochondria as a direct apoptogen to treat ovarian cancer, the most lethal gynecological malignancy with 69% of patients succumbing to this disease. Our next step will be to test these constructs in vitro in human ovarian cancer cell lines and in vivo using the syngeneic ID8 mouse model. 7-AAD cell death assay was performed in the mouse ovarian ID8 cells transfected with our constructs. p53-Bax-MTS and p53-BakMTS appear to be the two most effective constructs. Interestingly, full length p53 is required for its apoptotic activity in this ID8 mouse cell line. In terms of the P72R polymorphism, p53(72R)-BakMTS and p53(72R)-BaxMTS do not show enhanced apoptotic potential in the ID8 mouse line, most likely due to the sequence differences between human and mouse p53. However, it is possible that the combination of 72R polymorphism with MTS from Bak and Bax may produce a superior mitochondrial localization of p53 in human cell lines. Our ultimate goal is to develop mitochondrially targeted p53 constructs that directly induce apoptosis for the treatment of ovarian cancer.
Acknowledgements: NIH CA151847
Citation Format: Phong Lu. Targeting p53 with Bak and Bax mitochondrial targeting signals for the treatment of ovarian cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2927. doi:10.1158/1538-7445.AM2015-2927
Abstract 2975: Comprehensive analysis of genetic alterations and DNA copy number in Borrmann type IV gastric cancer
Authors: Yasumoto Makiko , Ogasawara Sachiko , Akiba Jun , Kusano Hironori , Sumi Akiko , Isobe Taro , Kizaki Junya , Akagi Yoshito , Torimura Takuji , Sakamoto Etsuko , Itadani Hiraku , Kobayashi Tsutomu , Mizuarai Shinji , Oie Shinji , Yano Hirohisa 
Published: August 2015

Abstract
The prognosis of patients with Borrmann type IV gastric cancer (Type IV) is extremely poor. Thus, there is an urgent need to elucidate the molecular mechanisms underlying the oncogenesis of Type IV and to identify new therapeutic targets. Although previous studies using whole-exome and whole-genome sequencing have elucidated genomic alternations in gastric cancer, no reports have focused on the comprehensive genetic analysis in Type IV. To find cancer relevant genes in Type IV, we performed whole exome sequencing and genome-wide copy number analysis on 14 patients of Type IV. The exome sequencing identified a total of 182 somatic mutations which cause amino-acid substitutions or splice-site alterations. Previously reported mutations in gastric cancer were detected, such as ARID1A, CDH1, TP53 and RHOA. Moreover, our study has found novel mutations that have not been reported in gastric cancer and other tumor types. Among the newly identified genetic alterations, a mutation in muscle RAS oncogene homolog (MRAS) was predicted to cause molecular dysfunction. MRAS belongs to the Ras subgroup of small G proteins, including the prototypic RAS oncogene, KRAS, HRAS, and NRAS. The MRAS mutation discovered by whole-exome sequencing was validated by mutation-specific PCR. To investigate the frequency of mutation in MRAS, we performed Sanger sequencing of additional 46 Type IV samples. A total of 9 non-synonymous mutations were discovered with a mutation frequency of 17%, showing that MRAS is recurrently mutated in Type IV. The genome-wide copy number analysis also showed that copy number was aberrant in 41 genes, including Insulin-like growth factor 1 receptor (IGF1R). The samples with IGF1R amplification showed remarkably higher expression levels of mRNA and protein compared with other samples. In conclusion, this is the first research to discover mutation in MRAS among human tumor samples, although introduction of artificially mutated MRAS is known to have oncogenic activity. In addition, these results suggested that MRAS mutation and IGF1R amplification could drive tumorigenesis of Type IV and could be a new therapeutic target for Type IV.
Citation Format: Makiko Yasumoto, Sachiko Ogasawara, Jun Akiba, Hironori Kusano, Akiko Sumi, Taro Isobe, Junya Kizaki, Yoshito Akagi, Takuji Torimura, Etsuko Sakamoto, Hiraku Itadani, Tsutomu Kobayashi, Shinji Mizuarai, Shinji Oie, Hirohisa Yano. Comprehensive analysis of genetic alterations and DNA copy number in Borrmann type IV gastric cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2975. doi:10.1158/1538-7445.AM2015-2975
Abstract 298: Overcoming TGF-β-related immunosuppression for cancer immunotherapy by oncolytic adenovirus co-expressing Interleukin-12 and decorin
Authors: Oh Eonju , Choi Il-Kyu , Hwang June Kyu , Yun Chae-Ok 
Published: August 2015

Abstract
Interleukin (IL)-12 has been shown to be one of the most promising antitumor cytokines. The major antitumor activities of IL-12 rely on its ability to promote T helper type 1 (Th1) immune responses and CTL responses. However, immune suppression-dominated microenvironments in advanced tumors hinder the effect of IL-12 gene therapy for cancer. Most tumor cells produce large amounts of transforming growth factor-β (TGF-β), which plays crucial roles of tumor-induced immune suppression. The TGF-β inhibits proliferation of immune cells such as T, NK, and dendritic cells, resulting in suppression of antitumor immunity. Moreover, TGF-β is also known to regulate the maintenance and induction of regulatory T (Treg) cells. Thus, it has been hypothesized that inhibiting TGF-β might be an apt strategy for generating more effective cancer immunotherapy. Therefore, to enhance the efficiency of IL-12-mediated cancer immunotherapy, we generated oncolytic adenovirus co-expressing IL-12 and Decorin (hDCN) (RdB/IL12/hDCN) as suitable therapeutic adjuvant to overcome immune suppression by down-regulation of TGF-β through hDCN. Intratumoral administration of RdB/IL12/hDCN promoted enhanced antitumor effects compared with an oncolytic adenovirus expressing IL-12 or hDCN alone (RdB/IL12 or RdB/hDCN, respectively). We showed markedly elevated levels of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α and IFN-γ secreting cells in RdB/IL12/hDCN-treated tumors. Moreover, Treg in draining lymph nodes (DLNs) dramatically decreased in mice treated with RdB/IL12/hDCN, suggesting an association with the down-regulation of TGF-β in tumor treated with RdB/IL12/hDCN. Consistent with these data, tumor tissue injected with RdB/IL12/hDCN showed increased infiltration of CD4+ T and CD8+ T cells infiltration. Furthermore, hDCN enhanced viral distribution and tumor penetration, leading to improved virus-mediated cancer gene therapy by overcoming the extracellular matrix barrier within tumor masses. Together, these results provide new insight into the ability of hDCN to eliminate immune suppression and demonstrate that adenovirus co-expressing IL-12 and hDCN is a promising therapeutic tool for cancer treatment than adenovirus expressing IL-12 alone.
Note: This abstract was not presented at the meeting.
Citation Format: Eonju Oh, Il-Kyu Choi, June Kyu Hwang, Chae-Ok Yun. Overcoming TGF-β-related immunosuppression for cancer immunotherapy by oncolytic adenovirus co-expressing Interleukin-12 and decorin. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 298. doi:10.1158/1538-7445.AM2015-298
Abstract 303: Effect of scaffold on drug sensitivity of multicellular spheroids: Which method is close to in vivo and suitable for HTS
Authors: Masuda Norio , Mizuno Atsushi , Rahman M.Mamunur , Arai Kazuya , Itoh Manabu 
Published: August 2015

Abstract
Background: Three-dimensional (3D) cell culture models are more extensive to be better models than two-dimensional (2D) cell culture models due to enriched cellular signaling pathways, cell to-cell contact, more representative of tissue morphology, and predictive of drug responses in vivo. Different drugs screening and various biological responses between 2D and 3D cell culture models have been reported. However, very little information is available on cell function and/or drug susceptibility caused by a difference in methodology of three dimensional culture. Here, we compared drug responses of various cancer cells against distinctive anti-cancer drugs when grown in monolayer, scaffold 3D culture (Matrigel, NanoCuluture Plate (NCP)) or scaffold-free 3D culture models (ultra-low attachment round bottom plate), and also confirmed which method is suitable for high-throughput screening for robust three-dimensional screening model.
Method: We examined drug sensitivities of different lung cancer (A549, H226, H1650), breast cancer (SKBR-3, JIMT1), and prostate cancer (DU145) cell lines under monolayer or 3D cell culture conditions against several anti-cancer agents i.e. molecular targeted agent (Gefitinib, Afatinib, Temsirolimus, Vemurafenib, Vismodegib, Sorafenib), demethylation agent (Azacytidine, Decitabine), anti-microtubule agent (Docetaxel), alkylating agent (Cisplatin, Irinotecan), antimetabolite agent (5-FU, Gemcitabine, Methotrexate). The conditions of these assays are optimized for each culture method. Cell proliferation was measured by ATP assay. Furthermore, we analyzed the biological/ morphological differences among 3D culture methods (scaffold or scaffold-free culture models).
Result: Large variations in drug responses were observed among the different cell culture models. Cells grown in 3D scaffold culture model (NCP) were more drug sensitive than other cell culture models. Especially docetaxel, 5-FU, and methotrexate showed clear growth inhibition in three dimensional scaffold culture models (NCP) than scaffold-free culture models (round-bottom).
Conclusion: In this study, we showed that scaffold 3D culture is appropriate for anti-cancer drug-susceptibility test. We also proposed that NanoCuluture plate which is 3D scaffold culture model, can be used as a sophisticated high-throughput three-dimensional drug screening model.
Citation Format: Norio Masuda, Atsushi Mizuno, M.Mamunur Rahman, Kazuya Arai, Manabu Itoh. Effect of scaffold on drug sensitivity of multicellular spheroids: Which method is close to in vivo and suitable for HTS. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 303. doi:10.1158/1538-7445.AM2015-303
Abstract 3046: Glutamate dehydrogenase 1 signals through antioxidant glutathione peroxidase 1 to regulate redox homeostasis and tumor growth
Authors: Jin Lingtao , Li Dan , Alesi Gina , Fan Jun , Kang Hee-Bum , Zhou Lu , Boggon Titus , Magliocca Kelly , He Chuan , Arellano Martha , Khoury Hanna , Shin Dong , Khuri Fadlo , Kang Sumin 
Published: August 2015

Abstract
How mitochondrial glutaminolysis contributes to redox homeostasis in cancer cells remains unclear. Here we report that the mitochondrial enzyme glutamate dehydrogenase 1 (GDH1), commonly upregulated in human cancers, is predominantly important for redox homeostasis in cancer cells by controlling the intracellular levels of its product alpha-ketoglutarate (a-KG) and subsequent metabolite fumarate. Mechanistically, fumarate binds to and activates a ROS scavenging enzyme glutathione peroxidase 1 (GPx1) to regulate redox homeostasis, which provides a proliferative advantage to cancer cells and tumor growth. Our findings not only provide novel insights into understanding of the role of glutaminolysis in redox homeostasis but also suggest a novel signaling function of fumarate that regulates GPx1, allowing additional crosstalk between glutaminolysis, TCA cycle and redox status. Targeting GDH1 by shRNA or a newly identified small molecule inhibitor R162 resulted in imbalanced redox homeostasis, leading to attenuated cancer cell proliferation and tumor growth. Thus, our findings provide proof-of-principle suggesting GDH1 as a promising therapeutic target in the treatment of human cancers associated with elevated glutamine metabolism.
Citation Format: Lingtao Jin, Dan Li, Gina Alesi, Jun Fan, Hee-Bum Kang, Lu Zhou, Titus Boggon, Kelly Magliocca, Chuan He, Martha Arellano, Hanna Khoury, Dong Shin, Fadlo Khuri, Sumin Kang. Glutamate dehydrogenase 1 signals through antioxidant glutathione peroxidase 1 to regulate redox homeostasis and tumor growth. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3046. doi:10.1158/1538-7445.AM2015-3046
Abstract 3048: Study of mitochondria in multi-drug resistance and Polyphyllin D anti-cancer effect in hepatocellular carcinoma
Authors: Ngai Brandon Ho , Loo Jacky Fong Chuen , Kong Siu Kai 
Published: August 2015

Abstract
Liver cancer, being the sixth common cancer, causes approximately 700,000 deaths worldwide annually. Major treatment relies on chemotherapies because of the late diagnosis in many cases of liver cancer. However, the results are not satisfactory since the cancer cells develop multi-drug resistance (MDR), which greatly hampers the efficacy of multiple kinds of structurally different drugs, during the course of treatment. Several mechanisms of MDR were identified, the most notable one is the over-expression of ATP-binding cassette (ABC) transporters, such as P-glycoprotein (P-gp) and multi-drug resistance protein 1 (MRP-1), on plasma membrane. These transporters act as efflux pump of various types of chemo-drugs to accentuate the MDR phenotype. Nevertheless, the complete picture of MDR formation is yet to be explored. As mitochondria contribute vitally in apoptosis and energy production, in which both criteria are substantially altered in cancer context, we hypothesized that the organelle also takes part in the development of MDR in liver cancer. In our study, with the support of conventional assays such as western blotting and confocal imaging analysis, we adopted a novel approach by making use of the tunable resistive pulse sensing (TRPS) technique to characterize isolated mitochondria of HepG2 and R-HepG2, which corresponds to the native and multi-drug resistant liver cancer cell lines respectively. We identified a difference in volume and amount of mitochondria present in HepG2 and R-HepG2, plus the expression of P-gp and MRP-1 on mitochondria of R-HepG2. These suggest a potential role of mitochondria in MDR. On the other hand, a drug candidate Polyphyllin D (PD) was found to exert selective potency against R-HepG2. However, the mechanism is not lucid. We investigated the possible participation of mitochondria in this phenomenon and identified PD causes stronger swelling and membrane potential depolarization to isolated mitochondria of R-HepG2. Future attempt in elucidating pathways involved in PD toxicity will bring insight on designing therapeutics against cancer cells with MDR phenotype. This study also suggested future research in mitochondria can aid the discovery of more mechanisms in MDR development.
Citation Format: Brandon Ho Ngai, Jacky Fong Chuen Loo, Siu Kai Kong. Study of mitochondria in multi-drug resistance and Polyphyllin D anti-cancer effect in hepatocellular carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3048. doi:10.1158/1538-7445.AM2015-3048
Abstract 3049: BRAF status and low glutamine/glucose influence glutamine addiction modulated by oxidative stress in human melanoma cells
Authors: Rieber Manuel , Chavez-Perez Valery , Strasberg-Rieber Mary 
Published: August 2015

Abstract
BACKGROUND.- Cancer cells from solid tumors become metabolically stressed, when nutrients are insufficient within poorly vascularized regions. Metabolic stress results from severe deprivation of oxygen, glutamine and glucose, partly through excessive reactive oxygen species (ROS) production. Mutant BRAF can stimulate the accumulation of hypoxia-inducible factor-1alpha (HIF-1α) in physiological glucose and supplementation with supra-physiological glutamine in melanoma cells (Kumar SM et al, Cancer Res. 2007;67:3177-84).Although HIF1α reprograms melanomas to become highly glycolytic, this can be impaired in a microenvironment with sub-physiological levels of glutamine and glucose (Kwon SJ, Lee YJ.Clin Cancer Res. 2005;11:4694-700).,because melanomas require glycolysis and mitochondrial glutamine utilization. PURPOSE.- To compare proliferation and survival in response to glutamine and glucose restriction in wt-BRAF or mutant BRAF melanoma. EXPERIMENTAL. Determination of metabolic activity/proliferation and cell survival by fluorometric assays and crystal violet staining. RESULTS.- Glutamine depletion diminished survival even in physiological 5 mM glucose, particularly during hypoxia. However, 2.5 mM glucose or exogenous pyruvate when added together with another anti-oxidant N-acetylcysteine (NAC) partly substituted for glutamine in normoxic wt-BRAF cells. A much lower attenuation was seen in glutamine-depleted mutant BRAF cells when supplemented with NAC and pyruvate, particularly, under hypoxia. CONCLUSIONS.-1) glutamine restriction decreases metabolic activity and tumor cell survival, irrespective of BRAF status, being more toxic to mut-BRAF cells, either under hypoxia or in physiological glucose and normoxia,. 2) Antagonizing glutamine addiction may decrease tumor recurrence if combined with anti-BRAF targeted therapy.
Citation Format: Manuel Rieber, Valery Chavez-Perez, Mary Strasberg-Rieber. BRAF status and low glutamine/glucose influence glutamine addiction modulated by oxidative stress in human melanoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3049. doi:10.1158/1538-7445.AM2015-3049
Abstract 3055: Regulation of mitochondria-nuclear crosstalk in triple negative breast cancer
Authors: Park Jun H. , Vithayathil Sajna A. , Putluri Nagireddy , Tsouko Efrosini , Donti Taraka R. , Frigo Daniel E. , Creighton Chad J. , Lewis Michael T. , Sreekumar Arun , Wong Lee-Jun , Kaipparettu Benny A. 
Published: August 2015

Abstract
Driver pathways of triple negative breast cancer (TN BCa) is still poorly understood. Thus, it is important to identify the underlying mechanisms of TN BCa progression. Importantly, African American and Hispanic patients are more likely to be diagnosed of BCa at a younger age, have a higher probability of developing TN BCa. They also diagnosed with a more advanced stage of the disease compared to Caucasian women.
Src oncognenic pathway is one of the major tumor driving mechanisms in TN BCa. Src pathway is frequently over-expressed in TN BCa and Src inhibitors are one of their current treatments of choices. However, recent single drug therapy Phase-II trials with Src inhibitors failed to control unselected metastatic TN BCa. This raises some important questions on the underlying mechanism in the regulation of Src in TN BCa especially in aggressive metastatic BCa. Mitochondria, a semiautonomous organelle in cells, play an important role in cellular energy metabolism, free radical generation, and apoptosis. Mitochondria-nuclear crosstalk is a bidirectional pathway of communication between mitochondria and nucleus that influences many cellular and organismal activities. This crosstalk can regulate several oncogenic pathways involved in tumorigenesis. Using transmitochondrial cybrid (cybrid) technology, we generated different cybrid models under common nuclear background of TN BCa. Mitochondria from cells of different cancer potential including benign breast epithelium, moderately and highly metastatic breast cancer cell lines were used to understand cancer mitochondria regulated tumor pathways. Extensive analysis of cybrid models as well as confirmation in parental cell lines and other tumor models suggested that autophosphorylation of c-Src is regulated by mitochondrial tumor characteristics.
Ongoing studies using knock-down and over expression approaches focus on the role of specific mitochondrial proteins that are responsible for mitochondria-nuclear crosstalk and the regulation oncopathways in TN BCa.
Citation Format: Jun H. Park, Sajna A. Vithayathil, Nagireddy Putluri, Efrosini Tsouko, Taraka R. Donti, Daniel E. Frigo, Chad J. Creighton, Michael T. Lewis, Arun Sreekumar, Lee-Jun Wong, Benny A. Kaipparettu. Regulation of mitochondria-nuclear crosstalk in triple negative breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3055. doi:10.1158/1538-7445.AM2015-3055