bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2134: Cyclosporin-A enhances cisplatin induced-apoptosis through inhibition PPIase activity of cyclophinlin A and Akt signaling pathway in a human tongue squamous cell carcinoma
Authors: Zhang Wenfeng , Huang Congfa , Zou Haixiao
Published: July 2012

Purpose: Chemoresistance is a serious problem in squamous cell carcinoma of the tongue, but the mechanism of resistance and strategies against the resistance have not been elucidated. Cyclosporin-A (CsA), an immunosuppressive drug that targets calcineurin and cyclophilin A (CypA), rencent studies show that it enhances apoptosis of chemotherapeutic drugs in various kinds of tumors. The aim of our study was to investigate whether CsA could enhance cisplatin induced apoptosis in tongue carcinoma.

Methods: In the present study, we examined the effect of cisplatin and CsA, individually or in combination in a human tongue squamous cell carcinoma cell line. Tumor cell growth, cell cycle, cell apoptosis, PPIase activity of cyclophinlin A and Akt phosphorylation were examined.

Results: A combination of cisplatin with CsA synergistically attenuates cell gowth viability and markedly increased cleavage of caspase-3 and cytoplasmic histone associated DNA fragments in tongue squamous cell carcinoma cells, compared with single-agent treatment alone. Moreover, anti-apoptotic proteins p53 and Bax/Bcl-2 ratio were significantly increased in the combination therapy group. In contrast, the PPIase activity of cyclophinlin A and Akt phosphorylation were evidently decreased by the combination effect.

Conclusion: Together, our data suggest that CypA and Akt signaling pathway play a key role in cisplatin resistance of the tongue carcinoma cells. The combination therapy with cisplatin and CSA can overcome the chemoresistance of cisplatin, this may be a potentially useful therapeutic option for the human tongue squamous cell carcinoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2134. doi:10.1158/1538-7445.AM2011-2134
Abstract 3909: Genomic and transcriptomic analysis suggest that primary pleomorphic sarcomas and leiomyosarcomas are two genetically distinct diseases
Authors: Rogatto Silvia R. , Silveira Sara M. , Villacis Rolando A R , Carvalho André L. , Soares Fernando A. , Cunha Isabella W.
Published: July 2012

Malignant fibrous histiocytoma was the most frequent pleomorphic soft tissue sarcoma (STS) histotype, until laborious investigation showed a differentiation in two thirds of the cases, thereby reclassifying many of the tumors into pleomorphic liposarcomas (LPS) and leiomyosarcomas (LMS). Pleomorphic soft tissue sarcoma without any histologically identifiable line of differentiation is designated as undifferentiated pleomorphic sarcoma (UPS). Gene expression studies in UPS initially suggested that the majority of tumors cluster with LMS and LPS but subsequent studies have identified distinct genomic and expression profiles in liposarcomas. In the present study, it was evaluated genomic and transcriptomic alterations in UPS and LMS samples (35 frozen samples) obtained previously to chemo and or radiotherapy and without metastasis at diagnosis. These primary tumors were extensively characterized by immunohistochemistry. Array CGH and large-scale gene expression analysis were evaluated using the Human 44K Agilent oligoarrays according to manufacturer's instructions. Array CGH data were extracted and flagged with Feature Extraction software (version 10.1.1.1), processed using Genomic Workbench Standard (version.5.0.14), with the statistical algorithm ADM-2 and sensitivity threshold of 6.0. DNA copy number alterations were compared with Database of Genomic Variants (DGV; http://projects.tcag.ca/variation/) and with a reference dataset obtained from 83 healthy Brazilian individuals. Genomic gains were more frequently observed in UPS whereas losses were commonly detected in LMS. Some genomic alterations were frequently observed in both groups. Gains at 7q21.13 and losses at 13q14.3 were the most frequent genomic imbalances verified in UPS and LMS, respectively. Gene expression data were extracted using the Feature Extraction software (v. 10.1.1.1) and analyzed by the R software (v. 2.9.2) e TMEV (v. 4.4.1). An unsupervised and supervised analysis was done using the Significance Analysis for Microarray software (SAM) (FDR 0% and 1000 permutations) and Pearson correlation. It was detected three clusters with 101 genes differentially expressed. One cluster was composed 10 UPS, the second with 13 LMS and the last one with both tumors. All genes that differentiated the groups are involved in pathways related to cancer. The identification of specific genomic and transcriptomic imbalances suggests that UPS and LMS might represent genetically distinct diseases and indicate putative molecular diagnostic markers by integrated data analysis.Financial support FAPESP and CNPq.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3909. doi:10.1158/1538-7445.AM2011-3909
Abstract 3911: Functional copy number alterations (CNAS) in oral cancer
Authors: Morris Luc G. , Ganly Ian , Taylor Barry , Singh Bhuvanesh , Viale Agnes , Heguy Adriana , Chan Timothy A.
Published: July 2012

Background: Alterations in DNA copy number can functionally affect genes and produce a transformed cancer phenotype. Discoevery of novel cancer genes can be facilitated by identifying genomic regions undergoing frequent, significant alteration. Array comparative genomic hybridization techniques have generated vast amounts of raw copy number data requiring computational analysis to identify aberrations likely to be functional. In this analysis, we present data from a comprehensive computational approach designed to robustly map chromosomal aberrations in oral cavity squamous cell carcinoma (OCSCC).

Methods: DNA was extracted from 31 microdissected OCSCC frozen tumors and hybridized with reference DNA on the Agilent 1M copy number array, containing nearly 1 million probes across the genome at high resolution. The RAE computational framework was used to identify CNAs. In this analysis, segmentation of probe data is first performed using paired reference HapMap data and individual-tumor thresholds to account for stromal admixture and tumor heterogeneity. Scores (single-copy gain, amplification, hemizygous loss, homozygous deletion) are then assigned, followed by soft discrimination thresholding and significance testing with false discovery rate correction. Regions of interest (ROIs) are then agnostically identified as regions of significant (FDR<0.01) alteration, expanded to adjacent loci to account for spatial and amplitude uncertainty. Finally, described copy number polymorphisms were excluded.

Results: 49 ROIs were identified, 27 amplification regions (chromosomes 3,4,5,7,8,9,11,16,18,20,21) and 22 deletion regions (chromosomes 2,3,4,5,7,8,9,10,13,15,16,18,19). ROIs ranged in prevalence from 6.5-77.4% of samples, and encompassed 0-483 genes (total=2799, median=4), and 0-13 microRNAs (total=77, median=0). Eleven ROIs were focal intragenic CNAs. Four ROIs contained no named genes or microRNAs. Hierarchical clustering identified 3 clusters, based on escalating levels of CNA. Complete gene details of the 49 ROIs will be presented.

Conclusions: We report significant regions of CNA in oral cancer, by applying a robust computational framework to identify recurrent chromosomal aberrations in OCSCC, which represent highly significant candidate functional events.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3911. doi:10.1158/1538-7445.AM2011-3911
Abstract 3921: Fen-1 inhibition: Synthetic lethal opportunities in Rad54B-defective tumours, ALT-pathway backgrounds and beyond
Authors: Johnson Laura , Hudson Kevin , Lau Alan , O'Connor Mark , Thommes Pia , Durant Steve T.
Published: July 2012

Flap endonuclease-1 (FEN-1) is a 5′-3’ exonuclease and a 5’ flap endonuclease, required for Okazaki fragment processing as well as for long-patch base-excision repair (BER) and non-homologous end-joining (NHEJ). From datamining AstraZeneca's extensive GeAZR database, as well as from Oncomine searches, FEN-1 is over-expressed in lung, ovary, bladder, gastric and 5-FU-resistant cancer cell lines. Screens carried out in yeast (Saccharomyces Genome Database) reveal over 250 genes as being synthetic lethal with the yeast homolog Rad27. Recently using human model systems, FEN-1 suppression was confirmed to be synthetic lethal with the human homolog of yeast Rad54B in Rad54B-deficient colorectal cancer (CRC) cell lines. FEN-1 suppression has also been reported to selectively sensitise hTERT-deficient ALT (Alternative pathway for lengthening telomeres) cell lines. To gain in-house confidence in this synthetic lethal target validation approach, we have used molecular tools to test synthetic lethal opportunities in matched Rad54B-RNAi-suppressed cell lines and confirm selective sensitisation. We also intend to explore further synthetic lethal backgrounds as well as in combination with chemotherapeutic standards of care.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3921. doi:10.1158/1538-7445.AM2011-3921
Abstract 3922: TFEB translocation renal carcinoma: Two cases of novel isoforms with unique clinicopathological features
Authors: Inamura Kentaro , Togashi Yuki , Fujiwara Mutsunori , Yamamoto Shinya , Yonese Junji , Fukui Iwao , Ishikawa Yuichi
Published: July 2012

Renal cell carcinoma (RCC) with t(6;11) translocation, involving the transcription factor EB (TFEB), is an extremely rare neoplasm with only 20 cases reported to date. According to the available clinical histories, TFEB translocation renal carcinoma (TFEB RC) is predominantly seen in children and young adults and generally indolent. So far, only two TFEB RC cases have been reported to result in metastases and patient death. We herein present two cases of novel isoforms of TFEB RC with unique clinicopathological features, involving a 37-year-old man and a 47-year-old man. Whereas the former case had an aggressive course, the latter case had the borderline features between TFEB RC and chromophobe type RCC histologically and immunohistochemically except for the nuclear staining of TFEB. Genetically, the former case had two variants of mRNA in RT-PCR analysis, one of which directly connected to the exon 3 of TFEB in sequencing analysis. The latter case had the fusion point of TFEB downstream of the wild-type ATG in exon 3, although the nuclear staining of TFEB was detected. Our data including the molecular characterization contribute to clarify this tumor entity genetically and clinicopathologically. Further investigations with additional new cases are required.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3922. doi:10.1158/1538-7445.AM2011-3922
Abstract 4072: Insulin and NADPH-generating enzymes as molecular targets to repress colon cancer cell proliferation
Authors: Al-Dwairi Ahmed , Brown Adam R. , Simmen Rosalia CM , Simmen Frank A.
Published: July 2012

An increasing body of evidence implicates obesity and the attendant hyperinsulinemia as major risk factors for human colorectal cancers. The lipogenic pathway supports growth and survival of colon cancer cells. In particular, inhibition of Fatty Acid Synthase (FASN) or Acetyl-CoA Carboxylase α (ACCα) induces apoptosis of colon cancer cells. The relative involvement in colon cancer initiation, progression and pathogenesis of cytosolic NADPH that is used in lipogenesis remains less clear. In the present study, we have determined the effects of insulin and the involvement of the major NADPH-generating cytosolic enzymes on proliferation of human colon cancer cell lines. Insulin (1-10 nM; to mimic normo- to hyper-insulinemic states) induced a significant increase (7-15%, p < 0.05) in proliferation of HT-29 and HCT-116 colon cancer cell lines in vitro (assayed by MTT assay). Addition of insulin augmented (by 5-10%) proliferation of both cell lines upon concurrent treatment with cancer chemotherapeutic agents (5-fluorouracil, oxaliplatin, irinotecan; each added at a dose < EC50). The insulin-mediated increase in HT-29 cell growth was associated with a 2-3 fold elevation in FASN gene expression and a 50% decrease in expression of the FASN-targeting micro RNAs, miR-103 and miR-107. However, insulin did not induce mRNA abundance for the cytoplasmic NADPH-generating enzymes [Malic Enzyme 1 (ME1), Glucose 6-Phosphate Dehydrogenase (G6PD), 6-Phosphogluconate Dehydrogenase (6PGD), or Isocitrate Dehydrogenase-1 (IDH1]. siRNA-mediated knockdown of FASN or of the individual major cytosolic NADPH-generating enzymes caused decreases in proliferation of HT-29 and HCT-116 cells (15-30%, p < 0.05) compared to the control scrambled siRNA. Data highlight pro-proliferative roles for insulin, FASN and cytosolic NADPH-generating enzymes in colorectal cancer cell growth. Implementation of pharmacologic and/or nutritional means to reduce serum insulin levels, enhance FASN miR expression and inhibit tumor cell NADPH-generation may serve as useful adjuncts for future cancer treatment and prevention. Supported by NIH grant RO1 CA136493 and the Arkansas Biosciences Institute.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4072. doi:10.1158/1538-7445.AM2011-4072
Abstract 4073: Effects of metabolic and mitochondrial-targeted compounds on ovarian cancer cells
Authors: Chan Daniel , Miskimins Keith
Published: July 2012

Ovarian cancer has the highest mortality rate of all the gynecological cancers in the United States, and is highly resistant to current forms of treatment. Metformin, a type II diabetes drug, and phenethyl isothiocyanate (PEITC), a component of cruciferous vegetables, were examined for their effects on ovarian cancer cell growth and survival. Although the exact mechanism of both drugs is not known, both have been found to inhibit complexes within the electron transport chain. Metformin is also known to activate the AMPK-LKB1 pathway, possibly downstream of complex I inhibition. We examined the effects of these compounds in vitro to evaluate the potential of electron transport chain inhibitors as novel therapies for ovarian cancer. To assess cell growth and death, hemacytometry with trypan blue exclusion was used in the ovarian cancer cell lines: SKOV3, OVCAR3, CAOV3, and PA-1. Induction of apoptosis was measured by Western blotting for intact and cleaved poly-ADP ribose polymerase (PARP). Western blotting was also used to determine endogenous levels of enzymes responsible for clearing reactive oxygen species (ROS). Levels of mitochondrial ROS production were measured by flow cytometry and confocal microscopy using the fluorescent probe MitoSOX. Metformin treatment was found to induce cell death in PA-1, arrest growth in OVCAR3 and CAOV3, and slow growth in SKOV3. PEITC treatment induced cell death through apoptosis in all tested cell lines at low micromolar concentrations. Metformin's inhibitory effects were partially reversed when growth medium was supplemented with succinate to bypass complex I. Low expression levels of anti-oxidant enzymes were also found to correspond with higher sensitivity to metformin and PEITC. Additionally, levels of mitochondrial ROS increased with treatment. Metformin and PEITC both show potential as ovarian cancer therapies. Complex I inhibition likely contributes to metformin's anti-cancer effects, as succinate supplementation was able to reverse growth inhibition. Additional work is necessary to determine if the increase in mitochondrial ROS is caused by electron transport chain complex inhibition and whether it is essential to the anti-cancer effects observed.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4073. doi:10.1158/1538-7445.AM2011-4073
Abstract 4079: Pilot study of copper chaperon ATOX1 in oncogenesis of colon cancer
Authors: Cai Huawei , Peng Fangyu
Published: July 2012

INTRODUCTION: Copper is an essential element for normal function of many cellular enzymes. Copper homeostasis is maintained by a delicate network of copper transporters, which include human copper transporter 1(hCtr1), ATP7A, ATP7B, and copper chaperons including ATOX1, CCS, and Cox17. It has been known that copper is required for cell proliferation and tumor angiogenesis. Human tumor xenografts in mice with increased uptake of radioactive copper could be localized with positron emission tomography. Copper hypermetabolism might play a role in oncogenesis of human cancers. Recently, it was reported that ATOX1 is a transcription factor involved in copper-stimulated cell proliferation. In this pilot study, we analyzed expression of ATOX in human colon cancer tissues compared with its expression in normal colon tissues. In addition, preliminary experiments were conducted to study potential role of ATOX1 in oncogenesis of colon cancer.

METHODS: Immunohistochemistry analysis was conducted to compare expression of ATOX1 in colon cancer tissues and normal colon tissues. A lentiviral vector encoding short-hairpin RNA (shRNA) specific for ATOX1 (Lenti-ATOX-shRNA) was constructed and used to transduce HCT-116 human colon cancer cells. Suppression of ATOX1 in HCT-116 cells transduced with Lenti-ATOX-shRNA (ATOX1-shRNA-HCT116) was confirmed by Western blot. MTT assay was conducted to assess effect of ATOX1 silencing on proliferation and sensitivity of ATOX1-shRNA-HCT-116 cells to copper, cisplatin and copper 8-hydroxyquinoline-2-carboxaldehyde thiosemicarbazide complex (CuHQTS), a new anticancer copper complex. The HCT-116 cells transduced by a lentivirus encoding a scramble shRNA (Scramble-shRNA-HCT116) were used as control.

RESULTS: Over-expression of ATOX1 is identified in all of human colon cancer tissue samples (N=10), compared with expression of ATOX1 in normal colon tissue samples (N=10). Suppression of ATOX1 with ATOX1-shRNA in HCT116 cells was confirmed by Western blot assay. However, the results of MTT assay revealed no significant effect of ATOX1 silencing on proliferation and sensitivity of ATOX1-shRNA HCT116 cells to copper chloride, cisplatin, and CuHQTS, compared with proliferation and sensitivity of Scramble-shRNA-HCT116 to these drugs.

CONCLUSIONS: ATOX1 holds potential as a new biomarker of colon cancer. Additional studies are necessary to determine the role of ATOX1 and other copper transporters in oncogenesis of colon cancer.

Key words: colon cancer, copper metabolism, copper chaperon, ATOX1

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4079. doi:10.1158/1538-7445.AM2011-4079
Abstract 4080: Metformin and rapamycin inhibit proliferation and alter glucose metabolism in endometrial and ovarian cancer cell lines
Authors: Zhou Chunxiao , Dickens Hallum , Robinson Jada , Gehrig Paola A. , Bae-Jump Victoria L.
Published: July 2012

Objectives: A well-established phenomenon of tumor cells is a shift in glucose metabolism from oxidative phosphorylation to aerobic glycolysis, termed the “Warburg” effect. Glycolysis is a much less efficient mechanism of producing ATP, suggesting that cancer cells may have an inherently high need for rapidly metabolized glucose. Glucose metabolism and growth control are tightly linked in proliferating cells and involve signaling pathways such as the PI3K/Akt/mTOR pathway. Metformin and rapamycin both exert their anti-tumorigenic effects through inhibition of the PI3K/Akt/mTOR pathway. Thus, our goal was to investigate the mechanism of action of metformin and rapamycin on proliferation and glucose metabolism in vitro using both endometrial and ovarian cancer cell lines

Methods: The endometrial cancer cell lines, ECC-1 and Ishikawa, and the ovarian cancer cell lines, CAOV-3 and SKOV-3, were used in these studies. Cell proliferation was assessed after exposure to metformin and rapamycin, and viable cell densities were determined by measuring conversion of the metabolic dye, MTT. Western immunoblotting was performed to determine the expression of the glucose transporters, GLUT1 and GLUT4, and phosphorylated glycogen synthase kinase-3 alpha and beta (GSK-α and GSK-β). Expression of phosphorylated S6, a downstream target of the mTOR pathway, was also evaluated by Western immunoblotting.

Results: Metformin and rapamycin both potently inhibited growth in a dose-dependent manner in the endometrial and ovarian cancer cell lines (IC50 of 1-10 mM for metformin and IC50 of 5-18 nM for rapamycin). Metformin and rapamycin also stimulated expression of the glucose transporters, GLUT1 and GLUT4, and increased phosphorylation of GSK-α and GSK-β among the endometrial and ovarian cancer cell lines. In parallel, S6 phosphorylation was decreased after treatment with metformin and rapamycin.

Conclusions: Metformin and rapamycin are both potent inhibitors of cell proliferation and potentially alter glucose metabolism in endometrial and ovarian cancer cells. These findings suggest that metformin and rapamycin may have two interrelated anti-tumorigenic benefits – inhibition of the PI3K/Akt/mTOR pathway and disruption of glucose uptake and utilization by tumor cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4080. doi:10.1158/1538-7445.AM2011-4080
Abstract 4083: Reduced carbohydrates in resistant aggressive tumors, The RECHARGE Trial: A safety and feasibility nutritional study in ten patients
Authors: Fine Eugene J. , Segal-Isaacson C.J. , Feinman Richard D. , Tomuta Nora , Romano Maria , Bontempo Maria , Sparano Joseph A.
Published: July 2012

Background: Many aggressive cancers share a glycolytic phenotype associated with increased 18F-2-fluoro, 2-deoxyglucose (FDG) positron emission tomography (PET) uptake. Carbohydrate restricted (CR) diets, by inhibiting insulin secretion, enlist plausible but unproven mechanisms to limit cancer growth.

Objectives: We evaluated safety/feasibility of a CR diet in patients with advanced FDG-avid cancers using a change in exit vs. baseline FDG uptake as a surrogate measure of tumor response using prospective EORTC criteria.

Methods: Patients with advanced, incurable cancers and FDG-positive scans were recruited. Eligibility required ECOG performance status of 0-2, normal hepatic, renal, and gastrointestinal function, no diabetes or recent weight loss (> 5% within 3 months), and a body mass index of >20 kg/M2. A supervised CR diet (5% of total kCal) was monitored weekly for macronutrient intake, body weight, serum electrolytes, betahydroxybutyrate concentrations [BHB]. An exit four-week PET scan was obtained.

Results: Ten subjects with advanced cancer completed > 26 days of the diet without associated adverse effects. Mean daily caloric intake decreased (35 + 6) % vs. Harris-Benedict formula's predicted energy requirements, and median/mean weight loss were 4.1% (range 0.0-6.1%.) and (4.1 + 0.7) %, respectively. One patient had advanced but indolent disease (14 years without chemotherapy). Among nine patients with pre-trial progressive disease (Table 1), 4 continued to progress on PET, and 5 did not. Non-progression (n=5) vs. continued progession (n=4) correlated (p=0.02) with three fold higher dietary ketosis but not with reduced energy intake (p=0.65).

Conclusions: Preliminary data suggest safety/feasibility of carbohydrate restriction in patients with advanced cancer, and that ketosis correlated with disease stabilization, supporting further evaluation of CR as a complementary approach in conjunction with standard therapies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4083. doi:10.1158/1538-7445.AM2011-4083
Abstract 4091: The oral iron chelator, deferasirox, induces apoptosis in myeloid leukemia cells through caspase-dependent activation
Authors: Kim Jung-Lim , Kang Han-Na , Kang Myoung Hee , Kim Jun Suk , Oh Sang-Cheul , Choi Chul-Won , Yoo Young-A
Published: July 2012

Iron plays a central role in the regulation of many cellular function. Recently several studies suggest that iron chelator, deferoxamine acts as an anti-cancer drug on various cancers. deferasirox(DFS) is a new oral iron chelator. Some of the papers has recently been reported that effect antiproliferative on leukemia cell by DFS but the effects of DFS on myeloid leukemia cells have not been clearly elucidated.

We measured the sensitivity of human leukemic cell lines (HL-60 and KG-1) to DFS using MTT assay. The proliferation of cells treated with DFS at various concentrations for various time was decreased in a dose-and time-dependent manner. Cell cycle analysis for subG1 fraction also detected the increased cell death in the cells treated with DFS. To determine whether DFS-mediated cell death was due to apoptosis in HL-60 and KG-1 cell lines, percentages of apoptotic cell were measured by staining with FITC-conjugated annexin V and PI. The percentage of apoptotic cells was significantly increased by DFS stimulation. Results by Western blotting and colorimetric assay indicated that DFS promotes apoptosis of human leukemic cells by both activating caspase-3 and -9 and inducing PARP cleavage. Furthermore, pretreated of leukemic cells with caspase inhibitor (z-V) significantly inhibited the DFS-induced apoptosis. In the in vivo model, treatment of leukemic tumor-bearing athymic nude mouse with DFS was showed significant decrease in tumor growth compared with treatment with DMSO.

These results demonstrate that a new oral iron-chelating agent, DFS, promotes apoptosis of myeloid leukemia cells via activating caspase 3/9, suggesting that DFS might be beneficial for iron-overloaded patients with myeloid leukemia, not only from iron chelation but also from reduction of leukemia cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4091. doi:10.1158/1538-7445.AM2011-4091
Abstract 4099: F-box protein 10, an NF-κB-dependent anti-apoptotic protein, regulates TRAIL-induced apoptosis through modulating c-Fos/c-FLIP pathway
Authors: Ge Rongbin , Wang Zongwei , Zeng Qing , Xu Xiaoyin , Olumi Aria
Published: July 2012

Background: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) holds great promise as a potential anti-cancer agent, but some tumors develop resistance to TRAIL. AP-1 family member, c-Fos, is an important modulator of apoptosis. Although F-box protein 10 (FBXL10) has been implicated to regulate an AP-1 family protein, significance and mechanism of FBXL10 in apoptosis has not been investigated.

Methods: In this study, different types of TRAIL-sensitive cells (A498, PC3, MBA-MD-231) and TRAIL-resistant cells (LNCaP, PC3TR) were used, and a quantitative analysis of apoptosis was performed by using MTS and caspase-3, PARP activity assay and flow cytometry assay of annexin V- and propidium iodide-stained cells. RNAi, Chromatin immunoprecipitation (ChIP), EMSA, hydrodynamic-based transfection, oligonucleotide decoy technologies were performed to analyze the molecular interaction between FBXL10, c-Fos and NF-κB. The anti-apoptotic role of FBXL10 in vivo was analyzed by Lexatumumab (an agonistic human monoclonal antibody against TRAIL-R2) intravenous injection into mice carrying xenograft prostate cancers. All statistical tests were two-sided.

Results: We found that FBXL10 was suppressed and c-Fos was upregulated in TRAIL sensitive cancer cells and xenografts after treatment with TRAIL. However, in TRAIL resistant cancer cells and xenografts, FBXL10 and c-Fos were not affected. Expression of FBXL11, a FBXL10 homologous protein and c-Jun, was not affected by TRAIL. Silencing of FBXL10 sensitized resistant cells to TRAIL. Conversely, over-expression of FBXL10 repressed TRAIL-induced apoptosis. To behave as an anti-apoptotic molecule, we found that FBXL10 directly binds and represses c-Fos promoter in vitro and in vivo. In addition, FBXL10 regulates c-FLIP, another anti−apoptotic molecule, by a c-Fos dependent pathway. We also found that expression of FBXL10 is NF-κB – dependent, and TRAIL or proteasome inhibitors down-regulate FBXL10 via inhibiting NF-κB signaling. Using ChIP, EMSA assays and oligonucleotide decoy technologies, we found that NF-κB -p65 directly binds the FBXL10 promoter in vivo and in vitro, and promotes expression of FBXL10.

Conclusions: Differentiating molecular mechanisms between TRAIL sensitive and TRAIL resistant cancer cells will improve the efficacy of apoptotic therapies for cancer patients. In this study, we demonstrate a novel functional role for FBXL10 as an anti-apoptotic molecule, and describe a new apoptotic mediated pathway that involves NF-κB/FBXL10/c-Fos/c-FLIP. Therefore, silencing FBXL10 can help overcome resistant cancer cells for pro-apoptotic therapies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4099. doi:10.1158/1538-7445.AM2011-4099
Abstract 4102: Differing molecular mechanisms involved in the sensitization of human renal cancer cells to TRAIL-induced apoptosis
Authors: Brooks Alan D. , Thompson Candace R. , Pompei Richard J. , Booth Nancy , Gustafson Kirk R. , Henrich Curtis J. , McMahon James B. , Sayers Thomas J.
Published: July 2012

We have previously shown that the proteasome inhibitor bortezomib (Velcade/PS-341) specifically sensitized certain human renal carcinoma (RCC) lines to apoptosis induced by the TNF family-member TRAIL. A high-throughput screen conducted by the Molecular Targets Laboratory identified several promising new TRAIL sensitizers. One of these novel TRAIL sensitizers was the natural product withanolide E. Withanolide E, in contrast to bortezomib, had no activity as a proteasome inhibitor. Also withanolide E could sensitize some human RCC to TRAIL that were resistant to the effects of bortezomib. Furthermore sensitizing concentrations of bortezomib were also cytostatic to the RCC, whereas those of withanolide E were not. Bortezomib treatment of RCC resulted in the appearance of various proteins associated with a stress response, yet these proteins were not elevated by withanolide E treatment. By contrast the antioxidant n-acetyl cysteine completely blocked the TRAIL-sensitizing effects of withanolide E but not those of bortezomib. This suggests that changes in cellular redox are important for the sensitizing effects of withanolide E but not those of bortezomib. In order to study the molecular basis for increased TRAIL-mediated apoptosis, we investigated proximal apoptosis signaling events at the death-inducing signaling complex (DISC). Both bortezomib and withanolide E treatments resulted in an enhanced activation of the apoptosis signaling enzyme caspase-8 following exposure of the RCC to TRAIL. However, immunoprecipitation of the DISC revealed that bortezomib treatment resulted in a 4-5 fold increase in the amount of DISC formed. By contrast withanolide E treatment did not significantly alter the amount of the DISC, but reduced levels of the antiapoptotic DISC component c-FLIP. Therefore, both compounds amplified the apoptotic signal from the DISC via distinct molecular mechanisms of action.

Funded in part by HHSN261200800001E

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4102. doi:10.1158/1538-7445.AM2011-4102
Abstract 4104: TRAIL-induced p38 activation is regulated by MEKK4 with positive feedback manner
Authors: Sun Bo K. , Kim Joo-Hang , Oh Seeun , Kim So Y. , Choi Hye J. , Lee Yong J. , Song Jae J.
Published: July 2012

Previously, we demonstrated that TRAIL-induced p38 activation was responsible for the increases of Akt catalytic and invasive activity. Interestingly, TRAIL induced dramatically Akt catalytic activation in TRAIL-sensitive cells, whereas TRAIL did not induce Akt catalytic activation in TRAIL-resistant cells, suggesting Akt catalytic activation during TRAIL-induced apoptosis is likely to be a compensatory mechanism of cells. Here, we further provide that MEKK4 is the upstream molecule of TRAIL-induced p38 activation, and its catalytic activity is repressed by caspase-8 inhibitor. This result suggests that the caspase-8 activation induced by TRAIL is indispensible for MEKK4 activation. The CIN85, an adaptor molecule with three SH3 domains also interacted with MEKK4 and dissociated from MEKK4 in the presence of p38 inhibitor, providing the possibility that p38 induced the recruitment of CIN85 to MEKK4 for its activation by positive feedback manner. For the examination of p38 with CIN85, in vitro kinase assay, site-directed mutagenesis, and siRNA technique were used whether CIN85 was phosphorylated by p38, and the exact site of phosphorylation, and for the study of biological significance of CIN85 during TRAIL-induced p38 activation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4104. doi:10.1158/1538-7445.AM2011-4104
Abstract 4176: The biology of circulating nucleic acid in non-small cell lung cancer and prognostic implication
Authors: Vinayanuwattikun Chanida , Sriurangpong Virote , Mutirangura Apiwat
Published: July 2012

Background: Increased amount of circulating nucleic acid in plasma or serum (CNAPS) of cancer patient had been confirmed in many studies. The source of CNAPS was still enigmatic however the correlation with prognostic outcome was confirmed in various types of cancer. These might be the effect of tumor-derived CNAPS, correlated with tumor burden; however the interaction of cancer and immune cell was not negligent.

Material and Method: Fifty-eight plasma of advanced non-small cell lung cancer (NSCLC) and 52 sex/age match healthy volunteer were studied. Total amount of CNAPS was measured. We further explored substantial biology proportion of CNAPS according to cell source by using epithelial-specific marker, methylated SHP-1 promoter 2 (mSHP1P2), and hematopoietic-specific marker, unmethylated SHP-1 promoter 2 (uSHP1P2). Clinicopathological parameters were included with these markers evaluation.

Result: Significantly increased amount of CNAPS in plasma of NSCLC compared with healthy volunteer. Median levels were 7.6 ngml-1 (range 1.3-49.8) and 4.6 ngml-1 (range 0.03-26.9) respectively (p = 0.002). The mSHP1P2 represented the increasing amount of tumor-derived CNAPS in NSCLC (p < 0.001). Contrast to uSHP1P2 which was the predominant portion of CNAPS in healthy volunteer. The mSHP1P2 level was correlated with prognostic strategy in NSCLC. Moreover proportion of uSHP1P2 level was also increased among NSCLC and it was related with survival outcome. Comparison CNAPS, mSHP1P2 and uSHP1P2 with baseline demographic parameters by multivariate analysis, total amount of CNAPS was the only independent parameter for prognostic assessment. The level of > 4.5 ngml-1 indicated shorter median PFS (2.6 months) and OS (4.7 months) while the level of < 4.5 ngml-1 indicated longer median PFS (5.6 months) and OS (>15 months) (p < 0.001).

Conclusion: Total amount of CNAPS in NSCLC was the valuable prognostic implication confirmed by our study, the impact of both tumor and immune cell-derived portion.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4176. doi:10.1158/1538-7445.AM2011-4176
Abstract 4187: Phospho-Akt status as a predictor of disease free interval in patients with muscle invasive transitional cell carcinoma of the bladder
Authors: McPherson Victor A. , Williams Andrew , Chan Susanne , Rizkalla Kamilia , Izawa Jonathan , Lewis John
Published: July 2012

Background: Akt is an ubiquitous signaling molecule that is associated with a wide array of biological effects including cell growth and proliferation. The dysregulation of Akt has been associated with cancer cell transformation, invasion and metastasis. While the roles of mutations in FGFR3, p53 and Ras have been the focus of the majority of studies of Transitional cell carcinoma (TCC) of the bladder, recent evidence suggests a link between the Akt pathway and the progression of TCC. Mutations in Akt pathway members have been identified in subsets of bladder TCCs, and Akt activation in TCC cell lines confers resistance to chemotherapeutics and promotes invasion in vitro. This led us to hypothesize that activated Akt may be an important biomarker in the progression of muscle invasive TCC. Methods: Tissue was obtained from 67 patients who had undergone radical cystectomy procedures for treatment of muscle invasive TCC. Tissue sections were taken from paraffin embedded samples and subjected to immunohistochemical analysis with anti Akt antibody to detect the activated form of Akt. A database of patient demographics, disease, treatment and survival parameters was generated and used to correlate 4, 12, 24 and 36 month disease-free intervals (DFI). Results: 53 of the 67 patients had sufficient follow-up to allow for DFI analysis. Of these 53 patients, 48 stained positively for pAkt, while 5 stained negatively. None of the pAkt negative patients had recurrent disease, while the pAkt negative patients suffered cumulative recurrence in 10, 19, 24, and 25 of the 48 patients at 4, 12, 24 and 36 months respectively. Chi square analysis reveals statistically significant differences in recurrence rates between pAkt negative and negative patients at 24 (p=0.0235) and 36 months (p=0.016). Tumor stage and nodal status were also strong predictors of recurrence. Conclusions: pAkt negative patients were found to have a significantly better prognosis for TCC recurrence, which indicates that pAkt status could be useful in helping to determine the prognosis for patients with muscle invasive TCC. These results lead us to speculate that the use of a serine threonine kinase inhibitor may prove to be therapeutically beneficial for TCC patients undergoing concurrent chemotherapy for their disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4187. doi:10.1158/1538-7445.AM2011-4187
Abstract 4193: Identification of a novel SIRT1/FEN1 interaction and their regulation by karyopherins
Authors: Feurstein Daniel , Anderson Jessica , Duckett Derek
Published: July 2012

The structure-specific flap endonuclease 1 (FEN-1) is a multifunctional enzyme that participates in various activities such as DNA replication, DNA repair and apoptotic DNA fragmentation. Several mechanisms, including protein-protein interactions, sub-cellular compartmentalization and posttranslational modifications have been proposed to explain how FEN1 accomplishes these various activities. For example, the C-terminus of FEN1 has been shown to be acetylated by the histone acetyl transferase protein (HAT) p300 which is known to result in a significant reduction in the DNA binding and nuclease activities of FEN1. We now demonstrate that the NAD-dependent class III histone deacetylase SIRT1 physically interacts with FEN1 and that the opposing deacetylation by SIRT1 subsequently restores the endonuclease activity of FEN1. Moreover, clonogenicity experiments suggest that genetic knockdown of FEN1 or SIRT1 in cancer cells sensitizes those cells to irradiation treatment. This is of significance as it has been observed that increased SIRT1 levels protect mice from irradiation-induced cancer. Furthermore, we have also identified two nuclear shuttling proteins, Karyopherin α2 and Karyopherin β1 as interacting partners of both SIRT1 and FEN1. Using mass spectrometry, immunoprecipitation combined with subsequent western-blot analysis and confocal microscopy we demonstrate that, under basal conditions, a significant amount of both SIRT1 and FEN1 is located in the cytoplasm of cells. However, after induction of DNA damage by the methylating agent MMS, Karyopherin α2 and Karyopherin β1 mediate the translocation of SIRT1 and FEN1 into the nucleus in a time dependent manner. In summary we describe a novel interaction between SIRT1 and FEN1, demonstrate that acetylation/deacetylation regulates FEN1 activity and that the Karyopherins α2 and β1 mediate the nuclear import of SIRT1 and FEN1 following DNA damage. Our results suggest that inhibiting the nuclear import or activation of FEN1 or SIRT1 could represent potential anticancer strategies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4193. doi:10.1158/1538-7445.AM2011-4193
Abstract 4201: Role of adenomatous poliposis coli (APC) in cigarette smoke condensate-induced accumulation of apurinic/apyrimidinic lesions and enhanced transformation of normal breast epithelial cells
Authors: Panda Harekrushna , Jaiswal Aruna S. , Gairola C. Gary , Narayan Satya
Published: July 2012

Active and passive smoking are major risk factors for cancer and have been implicated in the etiology of breast cancer. The mechanisms through which smoking promotes breast cancer are poorly understood. Our previous studies have shown that cigarette smoke condensate (CSC), a surrogate for cigarette smoke, induces transformation of normal human breast epithelial (MCF10A) cells in culture. We have described the involvement of a multifunctional protein, adenomatous polyposis coli (APC), in the CSC-induced transformation of MCF10A cells through the interaction with DNA polymerase β and 5’-flap endonuclease 1 (Fen1), and thus, the blockade of the BER pathway. In the present study, we have examined the underlying mechanisms involved in CSC and Benzo[α]pyrene (B[α]P)-induced transformation of MCF10A cells in which APC was overexpressed or knocked down. Our results suggest a positive correlation between the increased levels of APC expression with the decreased BER activity and concomitant accumulation of apurinic/apyrimidinic (AP)-site lesions. If not repaired on time, the cytotoxic and mutagenic AP-site lesions ultimately lead to enhanced transformation of MCF10A cells. These studies suggest a possible mechanism by which active and/or passive cigarette smoking might be linked with breast carcinogenesis. This work was supported by Flight attendant Medical Research Institute, Miami, FL to SN.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4201. doi:10.1158/1538-7445.AM2011-4201
Abstract 4203: EF24, a novel curcumin analogue inhibits oncogenic activation induced by radiation abscopal effect in distant mice lungs
Authors: Veeraraghavan Jamunarani , Natarajan Mohan , Awasthi Vibhudutta , Herman Terence S. , Aravindan Natarajan
Published: July 2012

Ascertaining the ionizing radiation (IR)-induced carcinogenesis through an abscopal effect would raise a paradigm shift in our understanding of the radiobiological effects and radiation carcinogenesis. EF24, a synthetic analog of curcumin with improved physicochemical properties has been shown to possess potent anticancer activity, both in vitro as well as in vivo. In this study, we investigated the oncogenic activation after IR in an organ (lung) distant from the exposure field. C57/BL6 mice either mock irradiated, exposed to single dose IR (SDR: 2 or 10Gy) or fractionated IR (FIR, 2 Gy/day for 5 days) with or without EF24 (i.p. 200μg/Kg, 3h prior to IR) treatment were sacrificed 1h through 2 weeks post-irradiation. All IR exposures were limited to the lower abdomen area (1cm diameter), while the rest of the animal was protected by a specially designed cerrobend shield. DNA binding activity of AP-1, E2F1, cFOS and FRA1 were examined using EMSA analysis. Transcriptional activation of 88 oncogenes was assessed using QPCR profiling. Phosphorylation of CREB and JNK were examined using immunoblotting. Cellular localization of JunB, JunC and JunD were analyzed by immunohisto staining. IR significantly induced AP-1, E2F1, cFOS and FRA1 DNA binding activity in lungs distant from the exposure fields. EF24 completely and persistently (up to 2wks) suppressed IR-induced distant effect on AP-1, E2F1, cFOS and FRA1 DNA binding activity. Second, EF24 completely suppressed all 52, 31 and 64 oncogenes that were significantly upregulated after 2 Gy, 10Gy and 2Gyx5D exposures. We observed a similar inhibitory effect of oncogene transcriptome even after 2wk with EF24 treatment. Third, a profound increase in JunB, JunC and JunD levels observed in distant lung tissue after IR were significantly inhibited by EF24. Fourth, we observed a profound inhibition of IR-induced CREB phosphorylation with EF24 treatment in distant lungs. Taken together, these data clearly demonstrated an induced abscopal carcinogenic response in mice lungs after clinically relevant doses of IR exposure. The findings further imply that systemic administration of EF24 could potentially inhibit DNA binding activity, transactivation and translation of oncogenes and thereby mitigate IR-induced oncogenic activation at distant site.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4203. doi:10.1158/1538-7445.AM2011-4203