bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4505: Polymorphisms in vascular endothelial growth factor (VEGF) and associated receptors as prognostic and predictive factors in advanced solid tumors
Authors: Eng Lawson , Amir Eitan , Azad Abul Kalam , Habbous Steven , Pang Vincent , van der Zee Anke-Hilse Maitland , Savas Sevtap , Mackay Helen , Liu Geoffrey
Published: August 2012

Introduction: Angiogenesis is an important host factor that is utilized by cancer cells to both grow and metastasize. In an attempt to halt the progression of cancer growth, new agents, such as bevacizumab, have been developed to target VEGF. Host genetic variability in the VEGF pathway may influence angiogenesis-dependent signalling during cancer development, cancer biology and therefore may impact on sensitivity to various therapies and survival. Here, we conducted a systematic review of the predictive and prognostic significance of polymorphisms in VEGF and VEGF receptor (VEGFR) and their isoforms. Materials and Methods: We performed a literature search of PubMed in July 2011 using the keywords and MeSH terms: {“angiogenesis,” “VEGF,” “VEGFR1,” “FLT1,” “KDR,” “VEGFR2,” “VEGFA,” “VEGFB,” “bevacizumab”} and “cancer” and “polymorphism”. Eligible studies were those comparing wild-type and variant polymorphisms and reporting one or more of the following outcomes: overall survival (OS), progression free survival, time to progression, time to recurrence, disease free survival, response rate or drug toxicities. Meta-analysis was performed for studies reporting identical outcome data for pre-specified polymorphisms. Results: We identified 44 prognostic studies and 12 predictive studies. There was marked inter and intra-disease site heterogeneity in the effect of polymorphisms on both outcome and response to therapy. Meta-analysis was possible for six polymorphisms (VEGF +936C>T, VEGF –460T>C, VEGF +405G>C, VEGF –1154G>A, VEGF –2578C>A and VEGF –634G>C) each of which reported the effect of wild-type and variant forms on OS. VEGF –634G>C showed a statistically significant improvement in OS (HR: 0.75, 95% CI: 0.57-0.98, p=0.03). There were non-significant associations between VEGF +936C>T with worse OS and VEGF +405G>C with improved survival (HR: 1.38, 95% CI: 0.96-1.97, p=0.08 and HR: 0.85, 95% CI: 0.72-1.01, p=0.07, respectively). There were no significant differences between homozygosity and heterozygosity for these polymorphisms. Conclusions: VEGF –634G>C appears to predict for improved outcome while VEGF +936C>T and +405G>C both show non-significant associations with outcome. These polymorphisms should be investigated in prospective studies to ensure standardization of measurement and reporting.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4505. doi:1538-7445.AM2012-4505
Abstract 4509: Mitochondrial DNA copy number is inversely associated with overall survival in non-small cell lung cancer
Authors: Hildebrandt Michelle A. T. , Pu Xia , Lippman Scott M. , Wu Xifeng
Published: August 2012

Mitochondria play an important role in generating energy for vital cellular functions. Alterations in mitochondria function due to mutations or copy number changes can potentially lead to tumorigenesis. Although previous studies have investigated the effect of mitochondrial DNA (mtDNA) depletion on cancer risk, no studies have assessed constitutive mtDNA copy number as a prognostic marker for overall survival in non-small cell lung cancer (NSCLC). Towards this, we measured mtDNA content by a quantitative real-time PCR assay in peripheral blood lymphocytes collected prior to treatment from 1,134 NSCLC cases seen at MD Anderson Cancer Center. A significant inverse dose-response trend was identified for mtDNA content and NSCLC risk (p-value: 0.0076). Those with the highest tertile of mtDNA content had the greatest reduction in risk of dying (HR: 0.81, 95% CI: 0.82-0.97, p-value: 0.014) and a highly significantly enhanced median survival time of 20.20 months compared to only 14.11 months for those with the lowest mtDNA content (p-value: 6.7x10-5). It is known that exposure to tobacco smoke results in the production of reactive oxygen species that can damage mtDNA. Therefore, we also performed stratified analysis based on smoking status. The effect in ever smokers (N=951) mirrored that of the overall population with a significant reduction in risk of death with increasing mtDNA content (p-trend: 0.008) and a dramatic nearly seven month survival advantage for those patients with the highest mtDNA content compared to the lowest (20.73 months compared to 13.98 months, respectively, p-value: 4.1x10-5). Interestingly, mtDNA content was not significant with overall survival in never smokers (N=183), suggesting that the effect in the overall population was driven by the ever smokers and that mtDNA alterations do not play a major role in the course of disease for this unique subgroup of NSCLC patients. Together, these results demonstrate that mtDNA content is a potential prognostic biomarker in NSCLC that can be measured non-invasively prior to treatment to provide needed information regarding course of disease to identify those at high risk for a poor outcome.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4509. doi:1538-7445.AM2012-4509
Abstract 4511A: KMO as a novel diagnostic and prognostic biomarker in canine mammary gland tumors
Authors: Chiang Yi-Lun , Lei Han-Long , Liao Albert Tai-Ching , Chu Rea-Min , Lin Chen-Si
Published: August 2012

The purpose of this study is to verify the candidate genes KMO associated with the progressive growth of canine transmissible venereal tumor (CTVT) in clinical application as biomarkers for spontaneous canine mammary gland tumors (cMGT). Canine mammary gland tumor shares similar characteristics with human breast cancer in histopathology and biological behavior. Both of them are hormonal-dependent, and they have similar genetic aberrations, signature profiles and cell signal pathways. These facts suggest that canine mammary gland tumor could be a referable tumor model for human breast cancer research. Our previous study has shown screening the gene expression of kynurenine 3-monooxygenase (KMO), an enzyme involved in tryptophan metabolism, could predict tumor malignancy and survival time of cMGT-suffering dogs. Here we intend to confirm KMO as a real cancer biomarker by investigating its protein expression in a serious of 54 cMGT cases, 29 of them were benign and 25 malignant collected at the Veterinary Hospital of National Taiwan University (VHNTU) with immunohistochemistry. The results indicated that KMO discriminated malignant cMGTs from benign ones, and about 73.3% of malignant cMGT showed strong expression of KMO. In addition, patients with strong KMO expression had markedly lower overall survival rate than those with negative or weak ones. Comparing to KMO investigations, increasing Human epidermal growth factor receptor 2 (HER-2) manifestation was also shown to correlate with tumor size and cMGT stages. A positive correlation between KMO and Ki-67 expression was found in our cMGT cases and it suggests KMO may contribute to tumor development by promoting cell proliferation. This study demonstrated KMO as a potential biomarker in tumor diagnosis and prognosis. It might offer new perspectives for clinical applications of cMGT and perhaps lead to advance in human breast cancer research.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4511A. doi:1538-7445.AM2012-4511A
Abstract 4517: Syndecan-2 methylation is an early detection biomarker for colorectal cancer with high sensitivity and specificity in small serum sample volumes
Authors: Hoehn Benjmain D. , Oh TaeJeong , Kim Na Y. , Moon Young H. , Kim Nam K. , Kim Tae S. , Shin Sang S. , Lee Seung H. , Jang Ik-Soon , An Sungwhan , Chung Hyun C.
Published: August 2012

BACKGROUND: Colorectal cancer (CRC) is a major cause of morbidity and mortality in the world. Epigenetics has been a useful tool in the development of sensitive and specific screening tests for CRC. Targeting genes highly methylated in CRC has allowed us to develop an accurate method to select novel candidate genes and validate their sensitivity and selectivity through testing in clinical samples. METHODS: We performed CpG microarray analysis using methylation enriched DNA from tumors and matched normal appearing tissues to identify genes methylated in CRC. We then applied a step-wise filtering method to narrow our field of candidate genes. Six genes were verified for high methylation-positivity in CRC cell lines and underwent negative selection in healthy normal samples using bisulfate-pyrosequencing. Genes SORCS3, SIM1, SDC2 were selected for low levels of methylation in normal tissue followed by verification with MSP-pyrosequencing. RESULTS: SDC2 was then selected because of high methylation levels in tumor and very low levels in normal tissue. SDC2 methylation levels were measured in 133 tumors and were found to be significantly methylated at all stages. Next, 500αl sera samples from 42 CRC patients were tested using qMSP which demonstrated sensitivity at 71.4% and specificity 92.9%. CONCLUSIONS: This study utilized refined technologies to identify and validate a novel candidate SCD2 for CRC screening in serum with high sensitivity and selectivity using only 500αl. These findings demonstrate a new level of candidate selection, verification and application that we feel will meet the need for a new minimally-invasive screening test.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4517. doi:1538-7445.AM2012-4517
Abstract 4523: Stool proteomics reveals new candidate biomarkers for colorectal cancer screening
Authors: Bosch Linda JW , de Wit Meike , Oudgenoeg Gideon , Hiemstra Annemieke , Mongera Sandra , Piersma Sander R. , Pham Thang V. , Grieken Nicole CT van , Droste Jochim S. Terhaar sive , Oort Frank A. , van Turenhout Sietze T. , Larbi Ilhame Ben , Mulder Chris JJ , Carvalho Beatriz , Jimenez Connie R. , Fijneman Remond JA , Meijer Gerrit A.
Published: August 2012

Background Colorectal Cancer (CRC) screening can save many lives. Many invitational large scale screening programs worldwide use stool tests like the fecal immunochemical tests (FIT), which detects human hemoglobin. Tumor-specific biomarkers have the potential to improve the performance of these tests but so far, no protein-based fecal test has proved better than the FIT. Although most biomarker discoveries are done in tumor-tissues, the presence and/or chemical nature of biomarkers may be different in samples that ultimately will be used for screening like stool. Measuring biomarkers directly in stool samples may therefore yield candidate CRC biomarkers that are stable in the fecal environment. Aim The aim of the present study was to identify tumor-specific protein based biomarkers for the early detection of CRC, by applying in-depth proteomics to stool samples from CRC patients and healthy controls. Material and method Stool samples were obtained from 10 subjects with negative colonoscopy and from 12 CRC patients. Proteins were analyzed by in-depth proteomics using gel electrophoresis and nano Liquid Chromatography coupled to tandem mass spectrometry (nano LC-MS/MS). Resulting MS/MS spectra were searched against the human IPI database (version 3.62). Proteins were analyzed by hierarchical cluster analysis and visualized in a heat map. Non-paired statistical analysis of spectral count data from human proteins was performed using a beta-binomial test. Verification of candidate biomarkers was performed by Selected Reaction Monitoring Mass Spectometry (SRM-MS). Results In total 830 human proteins were identified of which 221 were present at different levels in stool samples from CRC patients compared to control subjects. Of these, 134 proteins were significantly enriched in CRC. Unsupervised hierarchical cluster analysis revealed two clusters. One cluster contained nine CRC stool samples, the other cluster contained all ten control stool samples together with three CRC stool samples. SRM-MS analysis of selected candidate biomarkers on the same stool samples verified the results obtained by LC-MS/MS. Conclusion Proteome profiling on stool revealed 134 proteins significantly enriched in CRC compared to control stool samples, of which a sub set could be verified by SRM-MS. Validation in an independent series of stool samples collection (n=200) by SRM-MS is in process.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4523. doi:1538-7445.AM2012-4523
Abstract 4525: p21 as a predictive marker of pathologic complete response after 5-FU based chemoradiotherapy for patients with rectal cancer
Authors: Sim Sung Hoon , Kang Mi-Hyun , Kim Yu Jung , Lee Keun-Wook , Kim Duck-Woo , Kang Sung-Bum , Jang Na Young , Kim Jae-Sung , Lee Hye Seung , Kim Jee Hyun
Published: August 2012

Purpose: Pre-operative chemoradiation therapy (CRT) is standard treatment in clinical stage T3/4 or node positive rectal cancer, however, there are no established biomarker that can predict pathological response and clinical outcome to CRT. The aim of this study was to evaluate the correlation between expression of molecular markers and pathological response and clinical outcomes in patients with rectal cancer who received 5-FU based chemoradiotherapy. Experiment design: Immunohistochemical stain was performed in tissue arrays constructed from core tissue specimens taken before treatment and from operative specimens from 120 patients who received 5-FU based pre-operative CRT and surgery between June 2003 and Dec. 2008. Expression of Ki67, TS, BAX, EpCAM, p53, p21, EGFR, CD44, CD133, CD166, HIF1a and ALDH1 were assessed and correlated with tumor regression grades and disease free survival. Results Of 120 patients (M/F 77/43, median age:63), 23 (19.2%) patients achieved pathologic complete remission; Dworak grade 1: 18 (15%), grade 2: 51 (42.5%); Grade 3: 28 (23.3%), and Grade 4: 23 (19.2%). In the analysis of association between marker expressions and tumor regression grades, low p21 expression at pretreatment biopsy was significantly associated with grade 4 (total regression) (p=0.039) and better disease free survival (5yr DFS rate - low vs high p21: 89% vs 54%, p=0.001). In the multivariate analysis, low p21 expression level in pre-treatment biopsy was significantly associated with better DFS (p=0.003, HR 0.20; 95% CI 0.72, 0.57) and the score difference of p21 expression between pre- and post treatment tissue was also significant (p=0.002, HR 0.09; 95% CI 0.02, 0.39). Low CD166 expression level at pretreatment biopsy was associated with better DFS (p=0.003; HR 0.19; 95% CI 0.07, 0.58). Low ypN stage and high tumor regression grade also have significantly a good effect on DFS as well (p= 0.001, 0.018 respectively). Conclusion Our results showed low p21 and CD166 expression at pretreatment biopsy was associated with tumor regression and good prognosis in patients treated with 5-FU based chemoradioatherapy. Larger, prospective trials and functional studies are warranted to determine the role of p21 and CD166 as predictive biomarker of response to chemoradiotherapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4525. doi:1538-7445.AM2012-4525
Abstract 4526: Lumican and Versican predict good outcome in stage II and III colon cancer
Authors: de Wit Meike , Belt Eric J. , van Diemen Pien M. Delis , Carvalho Beatriz , Coupé Veerle M. , Stockmann Hein B. , Bril Herman , Belien Jeroen A. , Fijneman Remond J. , Meijer Gerrit A.
Published: August 2012

Background and Purpose: Tumor stroma plays an important role in the progression and metastasis of colon cancer. The glycoproteins versican and lumican are overexpressed in colon carcinomas and are associated with the formation of tumor stroma. The aim of the present study was to investigate the potential prognostic value of versican and lumican expression in the epithelial and stromal compartment of stage II and III colon cancer. Methods: Clinicopathological data and tissue samples were collected from stage II (n=226) and stage III (n=160) colon cancer patients. Tissue microarrays (TMAs) were constructed with cores taken both from the center and the periphery of the tumor. These were immunohistochemically stained for lumican and versican. Expression levels were scored on digitized slides. Statistical evaluation was performed using SPSS. Results: Versican expression by epithelial cells in the periphery of the tumor, i.e., near the invasive front, was correlated to a longer disease free survival (DFS) for the whole cohort (P=0.01), stage III patients only (P=0.01), stage III patients with microsatellite instable (MSI) tumors (P=0.04) and stage III patients with microsatellite stable (MSS) tumors who did not receive adjuvant chemotherapy (P=0.006). Lumican expression in epithelial cells overall in the tumor was correlated to a longer disease specific survival (DSS) in stage II patients (P=0.05) and to a longer DFS and DSS in MSS stage II patients (P=0.02 and P=0.004). Conclusion: In the present series, protein expression of versican and lumican predicted good clinical outcome for stage III and stage II colon cancer patients, respectively.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4526. doi:1538-7445.AM2012-4526
Abstract 4581: Pim-1 kinase inhibition in the absence of FLT3 inhibition results in cytostatic effects in acute myeloid leukemia cells
Authors: Natarajan Karthika , Burcu Mehmet , Baer Maria R.
Published: August 2012

The serine threonine kinase Pim-1 regulates expression of proteins involved in cell cycle, proliferation, apoptosis and drug resistance. Pim-1 has been identified as a potential therapeutic target in acute myeloid leukemia (AML). Notably, it is overexpressed downstream of FLT3 with internal tandem duplication (ITD), present in 30% of AML cases and associated with adverse treatment outcomes. SGI-1776 is the only Pim inhibitor in clinical testing to date, but testing was discontinued due to QTc prolongation. SGI-1776 has been used in laboratory studies of AML, but is also a FLT3 inhibitor, and effects of Pim-1 and FLT3 inhibition have been difficult to distinguish, particularly in cells with FLT3-ITD. To better characterize the effects of Pim-1 inhibition in AML, we compared SGI-1776 (from SuperGen, Inc., Dublin, CA) with two Pim inhibitors without FLT3 inhibitory activity, SMI-4a and quercetagetin in FLT3-wt and FLT3-ITD cells in 96-hour WST-1 cell viability, flow cytometric cell cycle and apoptosis, colony formation and liquid culture proliferation assays. SGI-1776 had no effect on cell cycle in FLT3-wt cells at concentrations up to 5 μM, and caused apoptosis at 10 μM, while G1 arrest and apoptosis occurred at 100 nM in FLT3-ITD cells, and SMI-4a and quercetagetin did not alter cell cycle nor induce apoptosis in FLT3-wt nor FLT3-ITD cell lines. IC50 (μM) comparisons are summarized below: In liquid culture assays, all three Pim inhibitors slowed proliferation of all cell lines, indicating a cytostatic effect. Thus FLT3 inhibition plays a substantial role in the cellular effects of SGI-1776, and Pim inhibitors without FLT3 inhibitory activity appear to have primarily cytostatic effects in AML cells. Other Pim kinase inhibitors in development should be characterized with regard to pro-apoptotic versus cytostatic effects.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4581. doi:1538-7445.AM2012-4581
Abstract 4602: Preclinical evaluation of the AKT inhibitor MK2206 in nasopharyngeal carcinoma cell lines
Authors: Ma Brigette B. , Lui Vivian WY , Hui Connie , Lau Cecilia , Ng Margaret , Tsao S W. , Hui Edwin P. , Wong C H. , Yan Li , Chan Anthony TC
Published: August 2012

MK2206 is an allosteric inhibitor of AKT with potent activity in cancer cell lines that exhibit genetic aberrations in the PI3K-AKT-PTEN pathway. AKT is frequently activated in nasopharyngeal carcinoma (NPC), while PIK3CA amplification is found in 40-70% of NPC tissues. The preclinical activity of MK2206 was evaluated in NPC cell lines: HONE-1-EBV, HONE-1, CNE-2, HNE-1, and 2 cell lines with PIK3CA amplifications, HK-1 and C666-1. All 6 cell lines showed increased basal level of activated (p-)AKT(ser473), p-GSK3β, p-mTOR, pi-p70S6K and p-4EBP1, except in C666-1 cells where p-70S6K and p-4EBP1 were weakly expressed. Basal expression of p-MAPK was most pronounced in HK-1, CNE-2 and HONE-1-EBV, and weakly expressed in C666-1 and HONE-1. The effect on cell growth was evaluated by exposing cells to increasing concentrations (conc) of MK2206 (100pM, 2nM, 20nM, 0.2µM, 2µM, 30µM) for up to 72 hrs followed by MTT assay. Over 95% of growth inhibition was achieved in all cell lines with respective IC50 values of: CNE-2=0.39µM, HK-1 = 0.48µM, HONE-1= 1.51µM, C666-1= 1.64µM, HNE-1= 1.92µM, HONE1-EBV= 2.36µM. CNE-2, HONE-1-EBV and C666-1 were selected for assessing the effect on AKT signaling, apoptosis, cell cycle and synergism with chemotherapy. Treatment of these cells with MK2206 at IC50 conc for 15 and 24 hours, resulted in G1 arrest in CNE-2 and HONE-1-EBV, and G2 arrest in C666-1 cells. Apoptosis (increased cleaved PARP) was detected in CNE-2 cells only. MK2206 reduced the expression of p-AKT, p-mTOR, p-BAD, p-FKHD and p-GSK3β in CNE-2, HONE-1-EBV and C666-1 cells, while the level of p-4EBP1 level was significantly reduced in C666-1 and CNE-2 cells only. The effect on p-70S6K expression in all 3 cell lines was minimal. MK2206 increased expression of p-MAPK in HONE1-EBV-1 and C666-1 cells, but not CNE-2 cells. A supra-additive effect on cell growth was observed when cisplatin was added to MK2206, while the effect of adding paclitaxel to MK2206 was minimal in all 3 cell lines. Our result suggests that MK2206 has activity in NPC in vitro. The increased expression of p-MAPK observed in some cell lines suggests the presence of compensatory MAPK activation as described with mTOR inhibitors in other cancers. MK-2206 is currently under clinical investigation in recurrent NPC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4602. doi:1538-7445.AM2012-4602
Abstract 461: Involvement of α9β1 integrin-iNOS pathway in matrix metalloproteinase-9 and/or urokinase plasminogen activator receptor-mediated glioma cell migration
Authors: Veeravalli Krishna Kumar , Ponnala Shivani , Zhuang Thompson , Chetty Chandramu , Rao Jasti S.
Published: August 2012

Src tyrosine kinase activates inducible nitric oxide synthase (iNOS) and, in turn, nitric oxide (NO) production as a means to transduce cell migration. Src tyrosine kinase plays a key proximal role to control α9β1 signaling. Our recent studies have clearly demonstrated the role of α9β1 integrin in matrix metalloproteinase-9 (MMP-9) and/or urokinase plasminogen activator receptor (uPAR)-mediated glioma cell migration. In the present study, we aimed to investigate the involvement of α9β1 integrin-iNOS pathway in MMP-9- and/or uPAR-mediated glioma cell migration. Immunohistochemical analysis of the glioblastoma multiforme (GBM) tissue array revealed the prominent presence of iNOS in several clinical GBM samples. In addition, immunofluorescence analysis of U251 glioma cell lines and 5310 glioma xenograft cells showed a prominent expression of iNOS. Transcriptional inactivation of MMP-9 and/or uPAR by respective shRNA reduced iNOS expression in both U521 and 5310 glioma cells. RT-PCR analysis revealed elevated iNOS mRNA expression in these glioma cells after transfection with MMP-9- or uPAR-overexpressing plasmids. Wound healing and spheroid migration assays showed a significant inhibition of the migration potential of MMP-9- or uPAR-overexpressed U251 glioma cells after treatment with L-NAME, an inhibitor of iNOS. Similarly, Matrigel invasion assay revealed a significant inhibition of the invasion potential of the control or MMP-9/uPAR-overexpressed U251 and 5310 glioma cells after L-NAME treatment. Further, we noticed a prominent reduction of iNOS expression in the tumor regions of nude mice brains, which were injected with 5310 glioma cells, after MMP-9 and/or uPAR knockdown. Integrin α9β1 regulates iNOS activity via Src tyrosine kinase; Src coordinates subsequent signaling pathways through activation of FAK and tyrosine phosphorylation of the adaptor protein p130Cas. Western blot analysis of MMP-9 and/or uPAR shRNA treated U251 and 5310 glioma cells revealed significant reductions in the protein expression of cSrc, phosphoSrc, FAK and p130Cas after simultaneous downregulation of both MMP-9 and uPAR. Taken together, our results from the present and earlier studies clearly demonstrate that α9β1 integrin-mediated cell migration utilizes the iNOS pathway, and inhibition of the migratory potential of these glioma cells by simultaneous knockdown of MMP-9 and uPAR could be attributed to the reduced α9β1 integrin and iNOS levels. Therefore, our results highlight the possible involvement of α9β1 integrin-iNOS pathway in MMP-9- and/or uPAR-mediated glioma cell migration.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 461. doi:1538-7445.AM2012-461
Abstract 4629: Tumor penetration and retention of different sized FGFR4 targeting scaffolds
Authors: Muchekehu Ruth , Pirie-Shepherd Steven , Coronella Julia
Published: August 2012

Poor drug concentration, distribution and retention pose significant obstacles to effective therapy of solid tumors. Antibody based immunotherapies must balance pharmacokinetics (PK), molecular weight and potency in order to maximize tumor penetration and retention. Low molecular weight constructs may have superior tumor diffusion properties, but short in vivo half life, whereas whole IgG molecules have improved PK properties and slow heterogeneous penetration. We hypothesise a molecule with a mass of 100-150 kDa and a KD of 1- 10 nM will have the ideal characteristics for maximum tumor penetration. A CovX-Body is the fusion of two targeting moieties (typically a peptide; in this study an FGFR4 targeting peptide is used) with an IgG scaffold. Constructs with variable molecular weights and affinities for FGFR4 have been generated by enzymatic digestion of the CovX body. As measured by ELISA, surface plasmon resonance (SPR), and flow cytometry (FACS), the bivalent CovX-Body and F(ab)2 constructs had similar FGFR4 binding properties (KD = 0.7 nM and 0.8 nM respectively), while the monovalent Fab construct showed ∼10-fold decreased binding (KD =11 nM). Initial in vivo studies measured total tumor levels of the full length CovX-Body in Colo205 Xenografts 72 hours post-injection with various doses. CovX-body levels were measured using an anti-idiotype CovX-body ELISA. The FGFR4-targeting CovX-Body reaches 8-fold higher total tumor levels compared to non-targeting CovX-bodies following a 10 mg/kg dose. Tumor penetration into the centre of the tumor was also measured, and showed 16-fold higher levels of the targeted CovX-body in the centre of the tumor compared to the non-targeting. Future work will involve measuring the biodistribution and tumor penetration properties of the different constructs. Lower molecular weight constructs should rapidly achieve high but transient levels of drug within the tumor, while IgG should achieve longer term, but lower intratumoral concentrations.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4629. doi:1538-7445.AM2012-4629
Abstract 464: CXCR7 protein is strongly expressed in B-acute lymphoblastic leukemia (ALL) but not in T-ALL or acute myelogenous leukemia
Authors: Sridharan Santhi , Mirza Imran , Marquez-Curtis Leah A. , Turner A. Robert , Larratt Lorree , Shirvaikar Neeta , Surmawala Amir , Janowska-Wieczorek Anna
Published: August 2012

The identification of CXCR7 in addition to CXCR4 as a receptor for the chemokine CXCL12/SDF-1 and recent reports that CXCR7 is expressed in many cancers including breast, lung and prostate prompted us to evaluate the role of CXCR7 in hematological malignancies. While CXCR4 is known to be involved in the progression of acute lymphoblastic leukemia (ALL) and acute myelogenous leukemia (AML), the role of CXCR7 in leukemic dissemination remains unknown. Using immunohistochemistry, we evaluated the expression patterns of CXCR7 and CXCR4 in tissue microarrays (TMAs) constructed from bone marrow biopsies obtained from patients diagnosed with pre B- and B-ALL (n=75; median age 5 yrs, range 6 mo-72 yrs), T-ALL (n=11; median age 12 yrs, range 4-29 yrs) and AML (n=140; median age 62 yrs, range 1-83 yrs). CXCR7 expression was also evaluated at the gene and protein levels in peripheral blood mononuclear cells from ALL and AML patients and in B-cell lines (Raji, NC-37, Ramos, Nalm-6, Reh), T-cell lines (Jurkat, Hut-102B, Sez-4, CEM), and myeloid cell lines (KG-1, HL-60, THP-1, U-937, K562, HEL) using RT-PCR and flow cytometry. We found that in B-and preB-ALL TMAs, CXCR7 was immunopositive in 79% of the patients, in contrast to negative immunostaining in 100% of T-ALL and AML samples. Consistently, flow cytometry showed that CXCR7 protein is expressed on the surface of preB-ALL cells, but not on T-ALL, AML or normal controls. CXCR7 surface expression in the cell lines studied showed that three (NC-37, Raji, Reh) out of five B-cell lines expressed CXCR7, but not in any of the T-cell lines, and only weakly in one (KG-1) of six myeloid cell lines studied. Analysis of the functional role of CXCR7 in leukemia revealed that CXCR7 did not mediate chemotaxis of CXCR7-positive NC-37 B-cell line and CXCR7-negative HL-60 myeloid cell line towards an SDF-1 gradient. However, CXCR7 was found to mediate the trans-endothelial migration, adhesion to HUVEC and survival of NC-37 cells, but not the adhesion to HUVEC or survival of HL-60 cells. In conclusion, the selective strong expression of CXCR7 in B-ALL but not in T-ALL or AML suggests a differential role this protein may play in various types of leukemia. As CXCR7 mediates trans-endothelial migration, adhesion and survival of B-cell line, further investigations into the functional role of CXCR7 in primary B-ALL are warranted with the aim of identifying new therapeutic targets.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 464. doi:1538-7445.AM2012-464
Abstract 4640: Development of antibody-drug conjugate technology based on novel DNA-interacting agents and unique linker technology
Authors: De Groot Vincent F.M.H. , Beusker Patrick , Joosten John , Spijker Henri , Coumans Ruud , Menge Wiro , Elgersma Ronald
Published: August 2012

Antibody-Drug Conjugation (ADC) is gaining momentum as a next generation antibody therapeutics approach in oncology. Tumor specific delivery of the cell-killing agent maximizes the agent's potency while avoiding damage to healthy tissue resulting in a high therapeutic window. Synthon's Potent Payload Technology comprises the combination of highly potent DNA-alkylating duocarmycin derivatives and unique releasable linker technology. Duocarmycin analogs and the CC-1065 derivatives represent a class of highly potent, cell-killing, DNA-alkylating, minor groove binding agents. This class is suitable to target solid tumors and has shown activity in a variety of Multi-Drug Resistant (MDR) models.Synthon SpaceLink technology is the only releasable linker technology for ADC that can couple the toxin via its hydroxyl group to the antibody, validated in vivo. Synthon has combined its linkers with duocarmycin derivatives that have a hydroxyl group crucial for biological activity. The data package to be presented supports that SpaceLink and duocarmycins form an excellent chemical match for ADC therapy, possessing an intrinsic complementarity. Strong in vivo Proof of Concept with Potent Payload ADCs has been obtained against multiple targets. In human tumor xenograft models, substantial efficacies have been obtained based on low, single dose treatments, with minimal or absent side effects. We discuss applicability and several other aspects of multiple, validated Potent Payload-based Antibody-Drug Conjugates (ADCs). Latest results of preclinical development progress (in vivo efficacy, safety, etc.) will be presented, including in vitro drug and ADC potencies, plasma stabilities, cathepsin cleavage kinetics, linker cyclization kinetics and in vivo therapeutic window aspects for ADCs directed against HER2 and potentially other (collaborator) targets.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4640. doi:1538-7445.AM2012-4640
Abstract 4647: Caspase-dependent post-translational modulation of Mcl-1 by ABT-737 in acute lymphoblastic cell lines
Authors: Ryu Yong-Ku , Kang Min H.
Published: August 2012

Background: ABT-737 is a BH3-mimetic that has a wide spectrum of single-agent activity against acute lymphoblastic leukemia (ALL) cell lines and xenografts. Previously (J Nat Cancer Inst 100:580-595, 2008), we reported that Mcl-1, an anti-apoptotic Bcl-2 family protein that is not inhibited by ABT-737, decreased in response to ABT-737 in ABT-737-sensitive ALL cell lines while a reactionary Mcl-1 increase is observed in ABT-737-resistant cell lines. In the current study, we investigated the pathways of Mc-1 down-regulation in response to ABT-737 in ALL cell lines. Methods: To identify caspase cleavage sites and to determine whether the cleavage products are pro-apoptotic or anti-apoptotic, we transduced into the NALM-6 ALL cell line lentiviral vectors with several Mcl-1 variants tagged with V5 epitope, including wild type: Mcl-1 1-350 full length tagged with V5, point mutations at aspartate 127 and aspartate 157 to alanine: Mcl-1 D127A and Mcl-1 D157A, and C-terminus fragments of caspase cleavage, deleted: Mcl-1 β127 and Mcl-1 α157. Localization of Mcl-1 1-350 and Mcl-1 β157 in ALL cells, cytosol and mitochondria were fractionated from the cells expressing the proteins, and Mcl-1 and V5 were assayed in the fractions. Results: The decrease in Mcl-1 by ABT-737 in ABT-737-sensitive cell lines was via formation of an Mcl-1 fragment which is prevented by a caspase inhibitor (Boc-d-fmk), but not a proteosome inhibitor (MG-132), indicating that Mcl-1 cleavage is caspase-dependent. Of the two caspase-dependent Mcl-1 cleavage sites (D127 and D157), D157 is the major site of cleavage in response to ABT-737 treatment in ALL cells. Localization experiments revealed that full length Mcl-1 resides in both the cytosol and mitochondrial fractions, while the Mcl-1_158-350 fragment localizes mostly to mitochondria. Caspase 3- and caspase 9-activation in response to ABT-737 was higher in transduced cells expressing the Mcl-1 β157 fragment, suggesting that the fragment increases sensitivity to apoptotic stimuli. Pretreating cells with okadaic acid, a protein phosphatase inhibitor, resulted in greater fragmentation of Mcl-1 in resistant cell lines while the effect of okadaric acid was minimal in a ABT-737-sensitive cell line, suggesting that dephosphorylation makes Mcl-1 more susceptible to Mcl-1 cleavage in response to ABT-737. Conclusion: Mcl-1 is cleaved to Mcl-1 β157 by caspases in ALL cells that are treated with ABT-737, and the pro-apopoptotic activity of Mcl-1 β157 contributes to a vicious cycle promoting cell death.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4647. doi:1538-7445.AM2012-4647
Abstract 4665: Sensitization of head and neck cancer cells toward cisplatin by inhibition of autophagy
Authors: Guo Changxiong , Rao Krishna , Robbins Thomas , Nie Daotai
Published: August 2012

Cisplatin is a commonly used chemotherapeutics but its efficacy is limited by the resistance presented by some tumor cells. Autophagy is a form of cell death by self-digesting organelles. The present study was undertaken to examine whether cisplatin can induce autophagy and whether autophagy modulates the efficacy of cisplatin against head and neck squamous cancer cells (HNSCC). In responses to increasing doses of cisplatin, there was a steady increase in autophagy, as indicated by LC3 punctate staining, in a cisplatin resistant UMSCC-15S cell line, whereas induction of autophagy was rapidly peaked at low doses of cisplatin in the UMSCC-10B cell line which was more sensitive toward cisplatin. Further studies found that there were increased autophagic fluxes at basal level in the cisplatin sensitive UMSCC-10B cells when compared to cisplatin resistant UMSCC-15S cells. Inhibition of autophagy by chloroquine significantly reduced colony formation of both cell lines, and sensitized UMSCC-15S cells toward cisplatin treatment. Our studies suggest that autophagy responses can be modulated to augment the efficacy of cisplatin against HNSCCs.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4665. doi:1538-7445.AM2012-4665
Abstract 4669: A combination of raloxifene and gefitinib potentiates the cytotoxicity and induces apoptosis in estrogen receptor negative breast cancer cell lines
Authors: Taurin Sebastien , Yadav Babasaheb D. , Nimick Mhairi , Rosengren Rhonda J.
Published: August 2012

In recent years, numerous studies have shown that the selective estrogen receptor modulators (SERMs) tamoxifen and raloxifene reduce the risk of invasive breast carcinoma. However, while SERMs do prevent the development of many estrogen-receptor (ER)-positive breast cancers, few studies suggest a potential effect of these drugs in the prevention of the development of ER-negative breast cancers. Although, the therapeutic efficacy of raloxifene in cancer therapy is thought to arise primarily from its ability to compete with estrogens; raloxifene has been shown to have effects through estrogen receptor (ER)-independent mechanisms. Recently, a study perform in our laboratory demonstrated that raloxifene decreased the level of EGFR expression in xenograft tumors. Based on these results, we hypothesized that a combination of raloxifene and a tyrosine kinase inhibitor, gefitinib may improve cytotoxicity towards ER-negative breast cancers. In the present study, we show that raloxifene (5µM) in combination with gefitinib (10µM) further decrease cell viability of two human ER-negative breast cancer cell lines, MDA-MB-468 and MDA-MB-231, compare to a single treatment from either of these two drugs. The combination potentiates apoptosis in MDA-MB-231 by 6 fold and in MDA-MB-468 by 3 fold after 36 h. Expression and phosphorylation pattern of proteins involved in cell proliferation such as NFκB, β-catenin, epidermal growth factor (EGFR) were also markedly affected by the combination treatment. Furthermore, evidence of apoptosis activation was also observed by an increase of the cleaved form of caspase-3. Additional studies demonstrated that the combination decreased cell migration and tumorigenicity of breast cancer cells. Moreover, the combined treatment decreased the ability of neovascularization as assessed by tube formation of endothelial cells. All together, these results suggested the potential of the combination of gefitinib and raloxifene for the prevention of tumor growth and appearance of metastatic events. In conclusion, these results provide us with the basis for future studies on the mechanism involved in raloxifene-gefitinib inhibition of ER-negative tumor growth.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4669. doi:1538-7445.AM2012-4669
Abstract 4672: Anti-angiogenic effects of zoledronic acid on osteotropic breast cancer cells
Authors: Contreras Cynthia , Morshedian Shaghayegh , Hamud Walid , Dhakal Bishal , Khanal Bijay , Bush Jason A.
Published: August 2012

Emerging data suggest the bisphosphonate, zoledronic acid (ZOL), exerts both indirect and direct anti-tumor effects by decreasing tumor cell proliferation, increasing apoptosis, and inhibiting angiogenesis. Recent data indicate that anti-angiogenic factors exert cellular effects via suppression of mitochondrial oxidative phosphorylation/respiration and elevation of intracellular ROS levels. This project intended to define proteins involved in response to ZOL-treatment of an osteotropic breast cancer cell line, MDA-231BO. Results demonstrate that MDA-231BO cells are more sensitive to ZOL cytotoxicity and salutary effects are both media- and calcium-dependent. To investigate pro-apoptotic mechanisms of ZOL, total RNA, whole cell protein lysates, or mitochondrial-enriched fractions were isolated from MDA-231BO cells and using a combination of RT-PCR, 1D/2D-PAGE separation and MALDI-MS/MS, we identified several angiogenesis inhibitors that were upregulated and pro-angiogenic factors that were downregulated after ZOL treatment. Functional studies demonstrate the improved efficacy of ZOL on MDA-231BO compared to MDA-MB-231 controls. Taken together, these results further support a model that ZOL tips the ‘angiogenic switch’ in favor of anti-angiogenic factors in cancer cells with a propensity for bone metastases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4672. doi:1538-7445.AM2012-4672
Abstract 4813: EMT inducers catalyze malignant transformation of mammary epithelial cells and drive tumorigenesis towards claudin-low tumors
Authors: Morel Anne-Pierre , Thomas Clémence , Hinkal George , Fauvet Frederique , Courtois-Cox Stephanie , Wierinckx Anne , Devouassoux-Shisheboran Mojgan , Tissier Agnes , GRAS Baptiste , Pourchet Julie , Puisieux Isabelle , Browne Gareth , Spicer Douglas B. , Lachuer Joel , Ansieau Stephane , Puisieux Alain
Published: August 2012

The malignant transformation of human epithelial cells is generally described as a multistep process resulting from the accumulation of five to seven rate-limiting changes. Here, we challenge this dogma and demonstrate that this number is radically reduced when cells undergo an epithelial-mesenchymal transition (EMT). EMT is an embryonic transdifferentiation process that consists of the conversion of polarized epithelial cells into motile mesenchymal ones. EMT-inducing transcription factors, including Twist and Zeb proteins, are aberrantly expressed in multiple tumor types and are known to favor the metastatic dissemination process. We demonstrate that, beyond their prometastatic potential, EMT inducers also act as potent drivers of tumorigenesis. We indeed show that the Twist1 EMT-inducing transcription factor promotes breast and skin cancer development in vivo in cooperation with the K-RasG12D oncoprotein. Importantly, in the model of breast tumorigenesis, transgene expression in differentiated mammary epithelial cells leads to the development of undifferentiated tumors exhibiting all the characteristic features of the claudin-low subtype. These observations challenge the concept that this tumor subtype specifically arises from transformation of an early epithelial precursor with inherent stemness properties and metaplastic features. Consistently, oncogenic cooperation assays performed in human mammary epithelial cells with Twist or Zeb EMT-inducers in combination with H-RasG12V generate transformed cell lines displaying all characteristics of claudin-low tumors including mesenchymal features, undifferentiated traits, and stem-cell-like properties. EMT might thus drive the development of claudin-low tumors by exhibiting a dual role in cell transformation and dedifferentiation. In other terms, the claudin-low tumor subtype of breast cancers might thus constitute a first example of human adult malignancies driven by aberrant reactivation of an embryonic transdifferentiation program.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4813. doi:1538-7445.AM2012-4813