bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1170: NFE2L2 gene mutation in Japanese lung cancer patients
Authors: Sasaki Hidefumi , Hikosaka Yu , Kawano Osamu , Okuda Katsuhiro , Moriyama Satoru , Yano Motoki , Fujii Yoshitaka
Published: February 2011

Recently, the nuclear factor (erythroid derived 2)-like 2 (NFE2L2, former NRF2) gene mutation was identified in lung cancers. The constitutive activation of NFE2L2 in lung cancer cells promotes tumorigenicity. However, the correlation between NFE2L2 mutation status and clinico-pathological features of lung cancer was not well reported. We have investigated NFE2L2 gene mutation status in 263 surgically treated lung cancer cases from Nagoya City University Hospital. The presence or absence of NFE2L2 mutation was analyzed by direct sequences. EGFR mutations status was already investigated and reported. We detected 13 case (5.1%) of NFE2L2 mutation in our cohort, especially in male and squamous histology (p<0.0001). Total EGFR mutations were present in 78 patients (30.8%). The NFE2L2 mutation was exclusive with EGFR mutations. The NFE2L2 mutation occurred tendency towards more frequent in patients with advanced stages. The patient with NFE2L2 mutation (n=13, 8 were dead) was significantly worse prognosis than the patient with wild type NFE2L2 (n=250, 72 were dead) (Log-rank test, p=0.0035, Breslow-Gehan-Wilcoxon test; p=0.0030). In our study, NFE2L2 mutations might play a role in tumor prognosis of squamous cell carcinoma of the lung.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1170.
Abstract 1171: Gastrointestinal stromal tumors (GIST) cell proliferation inhibition with combined adenoviral and molecular targeted therapy
Authors: Allen Derron E. , Arnoletti J. Pablo , Heslin Martin J. , Taguchi Takahiro , Kashentseva Elena A. , Dmitriev Igor , Frolov Andrey
Published: February 2011

Introduction: GIST, the most common mesenchymal malignancies of the GI tract, are characterized by gain-of-function mutations in KIT and PDGFRα receptors. Imatinib and sunitinib are tyrosine kinase inhibitors (TKI) currently approved for the treatment of GIST. Recent evidence suggests that GIST cells acquire secondary resistance to TKI through activation of alternative signaling pathways. We hypothesize that gene therapy with replicative vector oncolysis (virotherapy) can be utilized to improve efficacy of TKI and overcome GIST resistance to treatment.

Objectives: To determine if a panel of oncolytic adenoviruses in combination with imatinib and sunitinib, results in synergistic inhibition of GIST cell proliferation.

Results: GIST882 and GIST-T1 cells were subjected to imatinib and sunitinib treatment in combination with a panel of oncolytic adenoviruses (Ad5, Ad5RGD, Ad5pK7, and Ad5 - Ad3 fiber knob), to assess their inhibitory effects on cell proliferation. The Ad5/3 vector had the best rate of gene transfer and cytolytic effect. The greatest anti-proliferative effects were observed with 100 viral particles/cell of the Ad5/3 vector combined with TKI concentrations of 0.1 µM in GIST-T1 cell line. The combination of TKI and oncolytic adenoviruses showed greater inhibition of GIST cell proliferation (78% decrease) when compared to TKI alone (58% decrease) and viral therapy alone (23% decrease, p<0.01). Successful ex vivo infection and oncolysis of GIST by Ad5/3 particles was confirmed in cells obtained from patient surgical specimens (n=4).

Conclusions: The oncolytic adenovirus Ad5/3 infects and inhibits GIST cell proliferation both in vitro and ex vivo. Virotherapy with Ad5/3 has synergistic anti-proliferative effects with TKI and may help overcome GIST resistance to KIT targeted therapy.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1171.
Abstract 1180: MicroRNAs and their target messenger RNAs associated with progression of breast cancer
Authors: Schultz Silke , Petat-Dutter Karina , Walter Michael , Poths Sven , Vogel Ulrich , Bonin Michael , Sotlar Karl , Neuburger Christina , Wallwiener Diethelm , Fehm Tanja , Neubauer Hans J.
Published: February 2011

Background

Based on own results using laser micro dissected cells of invasive ductal (IDC) and ductal in situ (DCIS) breast cancer of the same tumor combined with Affymetrix microarray technology 445 differentially transcribed candidate genes have been identified (Schütz et al., Cancer Research 2006, 66:5278-5286). In this project differential expression of miRNAs and mRNAs was investigated in the same DCIS/IDC breast cancers and pure DCIS fixed in formalin and embedded in paraffin (FFPE).

Aims

The aim was (1) to identify miRNAs and their target mRNAs to serve as progression markers between DCIS and IDC and (2) to find an miRNA/mRNA set to characterize aggressive DCIS with a high invasive potential.

Material and Methods

Bioinformatic analysis using support vector machine and principle component analyses was applied to extract a prognostic gene set from the set of differentially expressed genes and qRT-PCR validation was carried out on micro dissected FFPE epithelial cells. Additionally, Illumina microarray technology was applied for mRNA and miRNA expression analysis. For functional analysis transmigration assays were performed in combination with siRNA mediated knock down of target genes.

Results

We obtained a 9-gene progression set which is able to correctly classify DCIS and IDC in 23 out of 24 cases (95.8%). Eight of the 9 possible marker genes were correctly validated in FFPE tissues. Further, expression of these genes also varied between pure DCIS and DCIS areas of DCIS/IDC mixed tumors - expression validation is currently done with qRT-PCR. Nineteen miRNAs were differentially expressed between DCIS and IDC, of which 4 had already been described in tumors. These 4 miRNAs have binding sites on 5 of the 9 candidate genes. Microarray analysis of mRNA from FFPE tissues confirmed differential expression of LRRC15 which has been found to be functionally relevant for breast cancer cell invasion and of LRRC32. An siRNA mediated knock down of LRRC32 reduced invasive potential of MDA-MB-231 breast cancer cells in transmigration assays.

Conclusions

A small gene set of potential progression markers obtained by microarray analysis of native breast carcinomas was successfully validated on FFPE tissues. In addition, a set of targeting miRNAs was identified that might thus serve as prognostic markers. Further analyses are still ongoing.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1180.
Abstract 1181: Expression of epithelial splicing regulatory protein 1 and 2 in ovarian cancer
Authors: Shoji Yutaka , Chirumamilla Siri , Chandramouli GVR , Risinger John I.
Published: February 2011

Epithelial Splicing Regulatory Proteins (ESRP1 and ESRP2) have recently been reported as RNA binding proteins that regulate epithelial specific splicing. We identified over-expression of ESRP1 and ESRP2 in ovarian cancer. The aim of this study was to determine the extent of expression of ESRP1 and ESRP2 in ovarian cancers and to examine whether its expression affects the abundance of the epithelial isoform of the Fibroblast Growth Factor receptor 2 (FGFR2) in ovarian cancer. Furthermore, we studied the regulation of FGFR2 splicing following knock-down of ESRPs in ovarian cancer cells. Affymetrix U133 Plus2.0 Array and quantitative real-time polymerase chain reactions (qRT-PCR) were used to measure gene expression levels in ovarian cancers and normal ovaries. ESRP1, ESRP2, epithelial specific FGFR2 IIIb and mesenchymal isoform FGFR2 IIIc mRNA levels were determined via qRT-PCR. RNA interference (RNAi) was used to knock-down ESRP1 and/or ESRP2 to examine its function on determining FGFR2 isoform expression in ovarian cancer cell line OVCAR3. Affymetrix GeneChip expression array analysis of 20 Stage IIIC serous ovarian cancers and 8 normal ovary surface epithelium brushings identified over-expression of ESRP1 (235 fold) and ESRP2 (33 fold). qRT-PCR confirmed that ESRP1 (7586 fold, p < 0.00001) and ESRP2 (21 fold, p <0.00001) were over-expressed in an independent set of 27 ovarian cancers compared to 11 normals. Since ESRP1 and ESRP2 function to drive the epithelial specific splicing of FGFR2, we examined the relative expression of FGFR2 IIIb and FGFR2 IIIc via qRT-PCR. The epithelial specific FGFR2 IIIb was over-expressed (313 fold; p < 0.00001), whereas the mesenchymal isoform FGFR2 IIIc was down-regulated (75 fold). RNAi knock-down of ESRP1 in OVCAR3 cells resulted in increased levels of mesenchymal specific FGFR2 IIIc (6 fold), but had a minimal effect on FGFR2 IIIb expression (−1 fold). ESRP2 knock-down had no detectable effect on FGFR2 IIIc and IIIb expression. However, ESRP1 and ESRP2 double knock-down results in the predominant expression of FGFR2 IIIc (25 fold) and down-regulation of FGFR2 IIIb (−3 fold) when standardized to a scramble control. Our results confirmed that ESRP1, ESRP2 and FGFR2 IIIb are over-expressed and FGFR2 IIIc is down-regulated in ovarian cancers. Also, results of RNAi double knock-down of ESRP1 and ESRP2 indicate that ESRPs drive the expression of the epithelial isoform FGFR2 IIIb in ovarian cancer cells. These data have implications on the ligand specificity of the FGFR2 receptor and for potential individualized therapies targeting FGF signaling in ovarian cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1181.
Abstract 1184: Prognostic significance of genetic alterations detected by high-density single nucleotide polymorphism (SNP) array in gastrointestinal cancer
Authors: Tada Motohisa , Kanai Fumihiko , Asaoka Yoshinari , Tanaka Yasuo , Tateishi Keisuke , Ijichi Hideaki , Ohta Miki , Seto Motoko , Sanada Masashi , Nannya Yasuhito , Imazeki Fumio , Yokosuka Osamu , Ogawa Seishi , Omata Masao
Published: February 2011

(Background and aims) We sought to identify specific gene that would be useful for predicting the prognosis of gastrointestinal cancer by the use of high-density single nucleotide polymorphism (SNP) array.

(Materials and Methods) We performed genome-wide analysis of 35 colorectal cancer (CC), 34 gastric cancer (GC), 17 Liver cancer and 26 pancreatic cancer cell lines using Affymetrix GeneChip Human mapping 100K Set. These analyses showed 10 remarkably recurrent homozygous deleted regions. These 10 regions were fine and contained only 1-2 genes, respectively. So, we chose 10 genes from these 10 regions and performed loss of heterozygosity (LOH) analyses using 64 CC (38 men and 26 women; mean age; 65.8±10.4 yr) and 42 GC (29 men and 13 women; mean age; 64.8±11.7 yr) tissues. For precise evaluation of LOH, laser capture microdissection was performed, minimizing the chance of contamination by non-tumor tissues. These 10 genes included the genes that have been not reported to be deleted in cancer besides FHIT and CDKN2A gene, which were known to be deleted in several cancers.

(Results) LOH of these 10 genes was detected in 35.5 %-74.6 % of CC and 39.0 %-67.5 % of GC tissues, respectively. We divided CC and GC into two groups (LOH-H; showing LOH of 5 genes or more, LOH-L; showing LOH of less than 5 genes), respectively. In CC, LOH-H showed a significant positive association with lymphatic invasion and lymph nodes metastasis (p = 0.007 and 0.04). On the other hand, LOH-H showed a significant positive association with lymph nodes metastasis (p = 0.019) in GC. The prognosis of the patients with LOH-L was significantly better than that of those with LOH-H in all CC cases (p = 0.038), while subgroup analysis showed that the prognosis of CC patients with LOH-L tended to be better than that of those with LOH-H in stage I + II CC cases (p = 0.057). Similarly, the prognosis of the patients with LOH-L was significantly better than that of those with LOH-H in all GC cases (p = 0.048). Subgroup analysis showed that the prognosis of the patients with LOH-L was also significantly better than that of those with LOH-H in stage I + II GC cases (p = 0.037). Multivariate analyses showed that stage and the LOH status were independent significant prognostic factors in CC and size and the LOH status were independent prognostic factors in GC.

(Conclusion)

LOH of these 10 genes might be a novel molecular signature of CC and GC with malignant phenotype.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1184.
Abstract 1185: Classification of lung carcinoma cell lines by integrated information of epidermal growth factor receptor and MET abnormalities and gene expression pattern correlates with response to chemotherapy and molecular targeted therapy
Authors: Matsubara Daisuke , Ishikawa Shumpei , Oguni Sachiko , Aburatani Hiroyuki , Fukayama Masashi , Niki Toshiro
Published: February 2011

Purpose: We have previously reported that lung adenocarcinoma cell lines could be classified into two groups based on the integrated information of epidermal growth factor receptor and MET abnormalities and gene expression pattern (2009 AACR annual meeting). In this study we sought to validate this classification by analyzing gene expression data set of primary lung adenocarcinomas. Also, we investigated whether this classification is clinically relevant to therapeutic outcomes.

Experimental Design: A panel of 40 lung carcinoma cell lines was analyzed. The activation levels of EGFR and MET were determined by Western blotting and gene expression data was obtained by Affymetrix Microarray. We retrieved gene expression data of 442 lung adenocarcinomas (Nature medicine, 2008, http://www.nature.com/nm/journal/v14/n8/abs/nm.1790.html?lang=en) and used them to validate our classification.

Results: Forty lung carcinoma cell lines could be classified into two distinctive groups. Group I (n=26) was characterized by high levels of TTF-1, MUC1, CK7, MET, HER3, E-cadherin, Cox-2, and lamininC2. In contrast, Group II (n=14) showed high levels of vimentin, FGFR1, and TCF8. Group I was characterized by high phosphorylation levels of MET and EGFR, and frequent mutation and amplification of EGFR and MET. In contrast, Group II exhibited low activation levels of EGFR and MET, and no mutation or amplification of EGFR and MET. We validated this classification by analyzing gene expression data of 442 lung adenocarcinomas. By hierarchical clustering we identified two clusters (Cluster A and B) that corresponded to Group I and II, respectively. Cluster A and B were similar in prognosis but among patients who received adjuvant chemo- or radiotherapy, Cluster B showed better survival than Cluster A. This finding was corroborated by analyzing in vitro sensitivities to chemotherapeutic and molecular-targeted agents: Group II cell lines showed a tendency to be sensitive to paclitaxel and cisplatin while they showed resistance to EGFR inhibitor gefitinib.

Conclusions: Lung adenocarcinoma cell lines can be classified into two groups with distinct gene expression patterns, genetic abnormalities and activation status of EGFR and MET. This classification will be clinically relevant with regard to clinical response to chemotherapy and molecular targeted therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1185.
Abstract 1188: Cell-of-origin determines genetic selection and defines T-cell acute lymphocytic leukemia sub-types in mouse models
Authors: Berquam-Vrieze Katherine E. , Nannapaneni Kishore , Zagorodna Oksana , Mullighan Charles , Meyerholz David K. , Copeland Neal , Jenkins Nancy , Knudson C. Michael , Scheetz Todd , Dupuy Adam J.
Published: February 2011

The cell-of-origin has yet to be identified for most forms of cancer. However, such knowledge would provide insight into the earliest events that initially distinguish a tumor cell from its normal cell-of-origin. Understanding and identifying these events are critical, as these early genetic changes may create targets that can be exploited therapeutically. Unfortunately, the tools to address this question have only recently become available.

We have recently completed a forward genetic screen to examine how altering the cell-of-origin affects genetic selection in cancer. To accomplish this we made use of a Cre-inducible Sleeping Beauty (SB) system to initiate transposon mutagenesis in hematopoietic stem cells (HSCs), thymic progenitor cells (TP) or late stage CD4+/CD8+ thymocytes (DP). Each of these approaches produced predominantly T-cell lymphomas with different characteristics. Analysis of transposon-induced mutations in each of the three lymphoma models revealed clear differences in their genetic profiles. For instance, the HSC model was defined by frequent mutations in Notch1 (∼58%). By contrast, lymphomas in the DP model did not have Notch1 mutations, but instead had frequent mutations in Myc, Gfi1, Whsc1 and Akt2. Interestingly, tumors that were initiated in thymic progenitor cells had a genetic profile similar to that seen in the HSC or the DP model.

Recently, a sub-type of T-cell acute lymphoblastic leukemia (T-ALL), called early thymic progenitor ALL (ETP-ALL) was described in which the tumor cells resembled ETPs in both surface marker and mRNA expression. In addition, ETP-ALL patients have a much worse prognosis than typical T-ALL patients. We compared gene expression signatures from a subset of HSC and DP lymphomas to that of ETP-ALL and typical T-ALL. Interestingly, tumors from the DP model have a similar gene expression to human ETP-ALL, while HSC tumors show a greater resemblence to typical T-ALL.

Our data indicate that ETP-ALL may not arise from an early thymic progenitor, but from a differentiated T-cell that has undergone anaplastic transformation. The implications of this study are that cell-of-origin cannot be inferred from analysis of protein or gene expression patterns in tumors. Our findings also suggest that differentiation state of the cell-of-origin plays a critical role in determining what types of mutations will be selected during transformation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1188.
Abstract 119: Stabilization of hypoxia-inducible factor-1α by the human rhomboid family-1 gene product RHBDF1
Authors: Zhou Zhuan , Li Luyuan
Published: February 2011

Hypoxia inducible factor 1α (HIF1α) is a key transcription factor in the maintenance of oxygen and energy homoeostasis. Increased levels of HIF1α in cancer cells are often associated with increased tumor angiogenesis, metastasis, drug resistance, and poor prognosis. We reported recently that the human rhomboid family-1 gene (RHBDF1) plays a critical role in facilitating tumor growth. Here, we show that RHBDF1 interacts with and stabilizes HIF1α. RHBDF1 gene-silencing with siRNA leads to markedly decreased HIF1α protein stability and down-regulation of HIF1α-targeted genes. However, HIF1α gene transcription and translation is unaffected. RACK1 and HSP90 are protein factors that compete for binding to HIF1α, causing either oxygen-independent degradation or stabilization of the latter. Protection of HIF1α from degradation by RHBDF1 is the result of a switch of HIF1α binding from RACK1 to HSP90. Stabilization of HIF1a can be abolished by using 17-allylaminogeldanamycin, an inhibitor of HSP90. Moreover, engineered over-expression of RHBDF1 leads to hypoxia-induced resistance of cancer cells to apoptosis-inducing agent Etoposide, an anticancer drug, apparently due to high HIF1α levels. These findings are consistent with the view that RHBDF1 may function as a chaperone to maintain HIF-1α stability.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 119.
Abstract 1194: The splicing isoform osteopontin-c contributes to ovarian cancer progression
Authors: Tilli Tatiana M. , Franco Vanessa , Robbs Bruno , Wanderley João , Borges Fabrício , Viola João , Weber Georg , Gimba Etel
Published: February 2011

Introduction: Osteopontin (OPN) is a secreted glycophosphoprotein that is involved in tumorigenesis and metastasis in many solid tumors. Alternative splicing of OPN mRNA generates 3 known species and proteins, OPNa, OPNb and OPNc. Objective and Methodology: The aim of the present work was to investigate the expression profiling and the functional roles of OPN isoforms in ovarian carcinoma. Here we investigate the expression of each OPN isoform in ovarian cell lines and ovarian tissues, by quantitative real-time PCR using OPN splice variants specific primer pairs. We then investigated the roles of each one of these isoforms by using in vitro and in vivo models. Cell proliferation, migration and anchorage independent cell growth analysis were performed using OvCAr-3 cells overexpressing OPNa, OPNb or OPNc isoforms. Tumor formation was evaluated in athymic nude mice inoculated with OvCar3 cells overexpressing each oisoform as compared to empty vector controls. Results: We show that OPNa and OPNb are expressed in all ovarian tissues analyzed. However, the isoform OPNc is selectively present in malignant and borderline ovarian tumors and malignant tumor cell lines, but not in benign and normal ovarian tissues. Cell proliferation, migration, anchorage-independent growth and tumor growth in vivo are dramatically increased in OvCar-3 cells overexpressing OPNc. In contrast, OPNa and OPNb do not present these same pro-tumorigenic properties. Conclusions: These results together provide compelling evidence that OPNc plays important roles in ovarian cancer progression. Firstly, OPNc is specifically expressed in borderline and malignant ovarian tumors. Secondly, OPNc expression facilitates tumor progression towards an aggressive phenotype. Targeting OPNc in ovarian cancer has potential as a novel therapeutic strategy.

Financial Support: CNPq, CAPES, FAPERJ, Swiss Bridge Foundation, FAF/MS

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1194.
Abstract 1197: The role of mitochondrial permeability transition pore complex proteins VDAC1, ANT, and cyclophilin D in prednisolone-induced apoptosis in B-Lineage acute lymphoblastic leukemia (ALL)
Authors: Jiang Nan , Koh Grace Shi Min , Kham Shirley Kow Yin , Chew Fook Tim , Yeoh Allen Eng Juh
Published: February 2011

The loss of mitochondrial membrane permeability is central to apoptosis. The mitochondrial permeability transition pore (PTP) complex, comprising of at least voltage-dependent anion channel 1 (VDAC1), adenine nucleotide transporter (ANT) and cyclophilin D (CyD), mediates the permeability of the mitochondrial membranes. We investigated the involvement of VDAC1, ANT and CyD in prednisolone (PRED)-induced apoptosis in 2 ALL cell lines: Sup-B15 (sensitive) and REH (resistant). After 24h exposure to PRED (10.0µg/ml), VDAC1 protein was consistently upregulated only in PRED-sensitive cell line, but remained unchanged in the resistant one. Co-administration of non-specific VDAC1 inhibitor, 4, 4′-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) with PRED, blocked PRED-induced apoptosis and caspase-3 activity only in sensitive cell line. Surprisingly, complete VDAC1 silencing using siRNA (Dharmacon) failed to abrogate PRED-induced apoptosis, suggesting that VDAC1 is not critical. We next investigated the other members of the PTP complex i.e., ANT and CyD. Co-administration of PRED and bongkrekic acid (BA) a specific inhibitor of ANT, also resulted in a dose-dependent inhibition of apoptosis and the caspase-3 activity. The combination of DIDS and BA, even at reduced doses by 60% and 96% respectively, is highly synergistic in inhibiting PRED-induced apoptosis and surprisingly reduced VDAC1 upregulation in PRED-induced apoptosis, unlike each agent alone. PRED did not alter the level of CyD protein and administration of specific CyD inhibitor, cyclosporine A (CsA), did not affect PRED-induced apoptosis. We conclude that ANT protein is central in the mitochondrial PTP mediated apoptosis during PRED treatment of ALL; VDAC1 and CyD are dispensable. ANT is upstream to VDAC1 and it upregulates VDAC1 during PTP activation in PRED-induced apoptosis. Our investigation provides the basis for looking at the role of mitochondrial PTP complex proteins especially ANT in PRED treatment in childhood ALL. This may provide new avenues to reverse resistance to therapy in patients with relapsed ALL.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1197.
Abstract 1200: Oncogenic KRAS sensitizes colorectal tumor cells to chemotherapy via p53-dependent induction of Noxa
Authors: de Bruijn Menno T. , Raats Daniëlle A. , Hoogwater Frederik J. , van Houdt Winan J. , Cameron Kate , Medema Jan-Paul , Rinkes Inne H. Borel , Kranenburg Onno
Published: February 2011

Oxaliplatin and 5-fluorouracil currently form the backbone of conservative treatment in patients with metastatic colorectal cancer. Tumor responses to these agents are highly variable, but the underlying mechanisms are poorly understood. Our previous results have indicated that the presence of oncogenic KRAS in colorectal tumor cells sensitizes these cells to chemotherapy. In the present manuscript we show that the sensitization of colorectal tumor cells to oxaliplatin and 5-FU by oncogenic KRAS is critically dependent on the presence of wild type p53. KRAS status did not influence p53 stabilization, p21 induction, or cell cycle arrest. A screen for induction of apoptosis regulators revealed that KRAS selectively promoted expression of the pro-apoptotic p53 target gene Noxa. Suppression of Noxa by RNA interference strongly reduced KRAS/p53-dependent apoptosis following exposure to chemotherapy, both in vitro and in tumor xenografts in mice. Noxa knockdown did not affect p53-dependent p21 induction or cell cycle arrest. Our results identify oncogenic KRAS as an important determinant of the cellular response to p53 activation following exposure to oxaliplatin or 5-FU, by facilitating apoptosis induction through Noxa.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1200.
Abstract 1201: Inhibition of ASK1 through phosphorylation of serine 967 by PI3K/Akt-mediated pathways
Authors: Puckett Mary C. , Goldman Erinn , Cockrell Lisa , Khuri Fadlo , Fu Haian
Published: February 2011

Cancer is characterized in part by dysregulation of cell survival and cell death signals. In particular, many tumors show upregulated PI3K/Akt activity, leading to sustained cell survival and suppressed cell death. Here we report the identification of the apoptosis signal-regulating kinase 1 (ASK1) as a downstream effector of the PI3K/Akt survival signaling pathway. ASK1 can be suppressed by PI3K/Akt signaling, leading to inhibition of apoptotic signaling. ASK1 normally functions as a mitogen activated protein kinase kinase kinase (MAP3K) that, when activated by stress signals, can evoke a signaling cascade leading to activation of the MAPKs JNK and p38. This activation can result in many cellular responses, but ASK1 is most notably known for its role as a critical regulator of apoptosis. Because of its crucial role in the balance between survival and death, ASK1 activity is tightly controlled. In particular, 14-3-3 can bind ASK1 and inhibit its activity when the kinase is phosphorylated at serine 967. However, the signals that regulate this phosphorylation event are currently unknown. Recent evidence suggests that PI3K/Akt mediated pathways may be involved in phosphorylation of serine 967 and, subsequently, inhibition of ASK1. Specifically, treatment of cells with growth factors including IGF-1 and PDGF increased phosphorylation of serine 967, as did overexpression of a constitutively active Akt mutant. In addition, expression of a kinase dead Akt mutant blocked growth factor induced serine 967 phosphorylation, indicating that Akt plays a role in mediating survival signals leading to inhibition of ASK1. In support of this notion, treatment with the inhibitors of Akt and PI3K also reduced serine 967 phosphorylation. Interestingly, treatment of cells with IGF-1 or overexpression of Akt was also able to protect serine 967 from H2O2 induced dephosphorylation. Taken together, our study reveals a novel effector site in ASK1 for the action of PI3K/Akt, which may offer a potential target for cancer therapeutic development. This work was supported by the NIH Pharmacological Sciences Training Grant T32 GM008602 and NIH/NCI Grant PO1CA116676 and USAMRMC05075002 to FRK and HF.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1201.
Abstract 1203: Coordinated regulation of intestinal radio-sensitivity by PUMA and p21
Authors: Leibowitz Brian J. , Zhang Lin , Yu Jian
Published: February 2011

p53-upregulated modulator of apoptosis (PUMA) has been shown to be vital for radio-sensitivity in the small intestine. PUMA ablation results in drastic radio-resistance, lengthening the survival of mice exposed to 15 Gy whole body irradiation and blocking apoptosis in the crypts. In contrast, we and others have found that p21 ablation leads to slightly increased radio-sensitivity. To better elucidate the relative and perhaps linked roles of PUMA and p21 in the intestinal responses to irradiation, we produced PUMA/p21 double knockout (DKO) mice. Initial experiments revealed that DKO mice responded similarly to PUMA KO mice within the first 24 hours after 15 Gy ionizing radiation as measured by the DNA damage response and apoptosis in the crypts. Both groups showed more rapid, though less sustained, phosphorylation of H2AX than wild-type (WT) mice, while displaying significantly less apoptosis in the crypts. However, DKO mice were found to have similarly enhanced overall radio-sensitivity as p21 KO mice. Further studies revealed that DKO and PUMA KO mice may not be equally effective at repair despite their similar kinetics in the initial DNA damage response. At 48 and 72 hours post-irradiation, the crypts in DKO mice had a substantial number of TUNEL+ cells, while those in PUMA KO or WT mice had almost none. At 48 hours after irradiation, the crypts in p21 KO mice also had a large number of TUNEL+ cells, which declined by 72 hours. Additionally, the crypt cells in DKO and p21 KO mice, but not in WT or PUMA KO mice, were found to be positive for both γ-H2AX and the mitosis marker phospo-H3, indicating abrogated cell cycle control likely due to a futile attempt at proliferation. These data further suggest that the protection of intestinal epithelium against radiation injury through ablation of PUMA requires a functional p21 checkpoint in addition to inhibition of crypt apoptosis. Additional studies are underway in our laboratory to further elucidate how these two proteins might coordinately regulate intestinal injury and regeneration by modulating the survival and proliferation of intestinal stem cells and progenitors following irradiation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1203.
Abstract 1208: Suppressor of cytokine signaling 6 (SOCS6) is targeted to mitochondria and regulates mitochondrial morphology and function
Authors: Lin Huan-Yu , Lai Rai-Hua , Lee Hsin-Chen , Wang Fung-Fang , Chen Jeou-Yuan
Published: February 2011

Mitochondria are highly motile organelles that constantly undergo fission and fusion. Impairment of mitochondrial dynamics is associated with mitochondrial dysfunction and frequently linked to the pathogenesis of neurodegenerative diseases and cancer. We have previously shown that loss-of-function of suppressor of cytokine signaling (SOCS) 6 is a frequent event in human gastric cancer and ectopic expression of SOCS6 sensitized cells to UV-induced apoptosis. In this study, we have identified SOCS6 as a novel mitochondrial protein that regulates mitochondrial dynamics. By confocal microscopy, we showed that ectopically expressed SOCS6 is predominantly localized in mitochondria, and that the carboxyl-terminal SOCS box is important for its mitochondrial localization. We further showed that localization of SOCS6 in mitochondria is accompanied with increased mitochondrial fragmentation with attenuated membrane potential, both of which can be reversed by coexpression of mitochondrial fusion proteins Mfn1 or Mfn2. Our data further suggested that SOCS6 interferes with mitochondrial dynamics by interrupting the fusion process. Firstly, SOCS6 expression severely impaired the dynamics and mobility of mitochondria in live cells as demonstrated by fluorescence recovery after photobleaching (FRAP) experiments. Secondly, SOCS6 expression significantly hampered intermitochondrial transfer and fusion in the somatic hybrid produced by PEG-induced fusion. Furthermore, elimination of the expression of endogenous SOCS6 by RNA interference technique led to elongated mitochondria, and conferred cells increased resistance to UV-induced apoptosis. Taken together, our data suggest that SOCS6 is a mitochondrial targeting protein involved in the regulation of mitochondrial dynamics.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1208.
Abstract 1211: Role of anchorage-independence in signaling pathway activation and cell survival in invasive breast cancer cell lines
Authors: Daubriac Julien , Boucher Yves
Published: February 2011

Resistance to anoikis - apoptosis induced by loss of matrix anchorage - is a key step in the metastatic process. In several cancer cell types including breast cancer cells, the anoikis-suppressing effect appears to be mediated by the PI3-kinase/Akt and MAP kinase signaling pathways. The aim of this study was to determine the involvement of signaling pathways in anoikis resistance in metastatic breast cancer cell lines. To study anoikis resistance, metastatic MDA-MB-231 and 4T1 cells were cultured on poly-HEMA-coated plates. Cell death was determined by detecting the sub-diploid population, by flow cytometry. Western analysis was used to assess the levels of phospho-Akt, phospho-p38 and cleaved-caspase-3. Our results show that loss of anchorage in MDA-231 cells reduces phospho-Akt levels, whereas in 4T1 cells - under both adherent and non-adherent conditions - the elevated level of phospho-Akt was not modified. Nevertheless, 4T1 cells undergo anoikis, which was dependent in part on the cleavage of caspase-3. In contrast, MDA-MB-231 cells were anoikis-resistant. Anoikis resistance correlated with the activation of p38 MAP-kinase. p38 phosphorylation was reduced in non-adherent 4T1 cells, whereas there was significantly higher levels of phosphorylated p38 in non-adherent than adherent MDA-MB-231 cells. The activation of p38 MAP kinase has been implicated in SDF1-CXCR4 signaling. One recent study has shown that CXCR4 inhibits anoikis in MDA-MB-231 cells, suggesting that CXCR4 or p38 blockade may induce anoikis in breast cancer. Thus our findings show that two metastatic breast cancer cell lines exhibit different sensitivity to anoikis, which is potentially associated with p38 MAP-kinase activity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1211.
Abstract 1214: TIMP-1 and the TIMP-1 interacting cell surface protein CD63 in cultured astrocytoma derived spheroids: expression and co-expression with stem cell markers
Authors: Aaberg-Jessen Charlotte , Schrøder Henrik D. , Andersen Claus , Brünner Nils , Kristensen Bjarne W.
Published: February 2011

In previous studies we have shown that the immunohistochemical expression of TIMP-1 (tissue inhibitor of metalloproteinases-1) and CD63 increases with tumor grade in astrocytomas grade II-IV. Moreover, we demonstrated that a high TIMP-1 protein expression in glioblastomas was associated with a shorter overall patient survival. Recent studies have suggested that TIMP-1 can prevent chemo-induced apoptosis and in a study, using human breast epithelial cells (MCF10A), it was demonstrated that the interaction of TIMP-1 and CD63 is necessary for the TIMP-1 anti-apoptotic pathway. The aim of the present study was to investigate the expression of TIMP-1 and CD63 in cultured organotypic multicellular spheroids (OMS) and cell line spheroids (CLS) derived from astrocytomas in order to assess spheroid models for future studies involving TIMP-1, CD63 and chemo-resistance. By investigating the spheroids immunohistochemically, we wanted to elucidate if TIMP-1 and CD63 are co-expressed within the spheroids and whether they are expressed by tumor stem like-cells, since these cells are known to be more resistant to chemotherapeutic treatment. In the present study OMS from nine astrocytomas and CLS from three commercial astrocytoma cell lines were included as well as the glioblastoma tumor stem cell line SJ-1 made in our laboratory. In general high levels of CD63 protein was detected in all the original tumors, whereas TIMP-1 was moderately expressed. TIMP-1 and CD63 expression in OMS was similar to the expression in the original tumors. TIMP-1 was expressed at low to moderate levels in CLS, whereas CD63 was expressed by all tumor cells in all spheroids. TIMP-1/CD63 double immunofluorescence staining was performed on selected OMS and CLS showing tumor cells expressing both proteins. Furthermore, double staining was performed with TIMP-1 and the stem cell markers CD133, nestin and Sox2 demonstrating that a population of the tumor stem like-cells expressed TIMP-1. In conclusion, this study shows that spheroid models can be used in future studies investigating the role of TIMP-1 and CD63 in chemo-induced apoptosis. Furthermore, these results indicate that a fraction of the tumor stem like-cells could be protected by TIMP-1/CD63 interaction.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1214.
Abstract 1219: Tubulin binding to mitochondrial VDAC: A new regulator of oxidative metabolism and apoptosis? A new role for tubulin
Authors: Sackett Dan L. , Begaye Adrian
Published: February 2011

Tubulin binding to the outer mitochondrial membrane (OMM) was first reported many years ago but the function was unknown; we showed recently that dimeric tubulin binds to VDAC, the major metabolite channel in the OMM, and that this results in closing the channel to ATP-ADP exchange, with a consequent drop in oxidative phosphorylation. This could act as a regulator of normal oxidative metabolism, but excess tubulin binding could also lead to changes in the inner membrane potential, and possibly lead to mitochondrial swelling and triggering of apoptosis. To evaluate the plausibility of this mechanism for either regulation of normal metabolism or induction of apoptosis, the concentrations of tubulin and VDAC in the cell need to be known, as a huge discrepancy in either direction could make the mechanism unlikely. We have used semiquantitative Western blots to measure the concentrations of tubulin and VDAC in total cell extracts from a number of cancer cell lines. As expected, we found tubulin to be an abundant protein (∼0.5 % of total protein), but we also found VDAC to be more abundant than perhaps commonly thought (∼0.2 % of total protein). Thus we conclude that tubulin regulation of VDAC permeability is a plausible mechanism. Further experiments are underway to test this mechanism and its role in induction of apoptosis by chemotherapy agents, especially microtubule-directed ones.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1219.
Abstract 1221: Apoptosis is regulated by MCPH1 via p38 MAPK
Authors: Jo Yong Hwa , Choi Yongung Eun , Park Hyun Mi , Yoon Kyung-sik
Published: February 2011

Microcephalin (MCPH1) is a member of the BRCA1 COOH terminal (BRCT) domain family of protein that involved in the cellular response to DNA damage. MCPH1 gene are associated with primary microcephaly (OMIM 251200), premature chromosome condensation, homologous DNA repair, chromosomal integrity, cell cycle arrest, telomerase activity and apoptosis. Recently reports, And MCPH1 is regulated the p53 phosphorylation in apoptosis, and enhanced E2F1-dependent apoptosis and the role of MCPH1 in p73 induction during DNA damage. And E2F1 activation leads to a transient increase in phosphorylation of the MAPK p38 and also leads to phosphorylation of p53 in apoptosis. But it is not unclear mechanisms that MCPH1/ E2F1 binging induced phosphorylation of p38 MAPK. We have used western blotting and immunopresipitation for detecting protein expression and also real-time PCR for RNA expression. Cell lines were used MCF7, MDA-MB231, MCF10A and U2OS. We use the anti-cancer drugs, as cisplatin and doxorubicin for induced the apoptosis. Anti-cancer drugs are induced the MCPH1 protein expression for 2h∼6h, but reduced for 24h. We show the binging between E2F1and MCPH1and p38 MAPK expressions. And MCPH1 regulates p38 expression in apoptosis.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1221.
Abstract 1226: The AH receptor plays a key role in mediating IL6 production in head and neck tumor cell lines
Authors: DiNatale Brett , Perdew Gary H.
Published: February 2011

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor conventionally viewed as binding exogenous ligands and mediating gene transcription through DNA binding. Our research has uncovered various structurally distinct ligands, both exogenous and endogenous, that are capable of binding the AHR. We have also recently shown that combinatorial treatment of human breast and cervical cancer cell lines with an AHR ligand and an inflammatory signal results in synergistic induction of interleukin 6 (IL6). Squamous cell cancer of the head and neck is an umbrella term for malignancies developing in numerous locations, including the pharynx, larynx, tongue, and oral cavity. These tumors are often aggressive in nature, with high rates of metastasis to regional lymph nodes. Treatment has historically included radical or modified neck dissection to remove lymph nodes and frequent adjuvant chemotherapy and/or radiation therapy. IL6 production within HNSCC microenvironments both by cancer cells and by tumor-infiltrating macrophages has been shown to correlate with invasive, proliferative, and anti-apoptotic abilities of HNSCC cells, as well as human disease prognosis and recurrence rates. In studying a number of HNSCC cell lines, we have found many to have relatively high basal IL6 production. Using HNSCC2095 as an example, the AHR dependency of basal IL6 production was shown by means of siRNA-mediated AHR knockdown, as well as mediation of basal IL6 transcription following treatment with an AHR antagonist. ChIP assays reveal a significant level of basal AHR occupancy at the IL6 promoter, and antagonist treatment leads to dismissal of the AHR and a combination of coactivators. Similarly, AHR dismissal results in higher occupancy of transcriptional repressors. Key activators lost with AHR dismissal include p65, HDAC3, and BRG1. Following AHR dismissal, an increased presence of dimethylated histone H3 and HDAC1 occurs; both of which are typically repressive. Dismissal of the AHR from the IL6 promoter also leads to a decrease in the IL6-induced STAT3 signaling feedback loop seen in HNSCC lines. Constitutively active STAT3 has been examined as a therapeutic target in HNSCC due to its ability to increase tumor growth and anti-apoptotic effects. Our research shows that AHR binding to the IL6 promoter in HNSCC lines is required for constitutive cytokine production and plays a key role in STAT3 activation. These findings highlight the AHR as a potential target in mediating the autocrine loop of pro-growth signaling in human head and neck cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1226.