bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5424: Development of selective therapy of childhood ALL and Ewing's sarcoma using targeted-hybrid polymerized liposomal nanoparticles (HPLN)
Authors: Kang Hyunggyoo , Shahbazian Violette , Schafenacker Amanda , Nagy Jon , Triche Timothy
Published: May 2015

Until now a lot of understanding and research of cancer biology can make it possible to develop many anticancer drugs which can inhibit the specific pathways required for growth, proliferation, and survival of cancer cells. The current success in cancer therapy using these drugs improves the survival rate of patients but unfortunately it is not the case of all cancers and still many different kinds of cancers continue to have a poor prognosis. Furthermore the incompleteness of cancer therapies causes a variety of side effects such as secondary cancers, heart or lung damage, infertility or chronic hepatitis. Therefore a reliable tumor specific therapy is urgently needed to treat cancer patients. It is widely recognized that the recent chemotherapy could be far more effective if higher doses could be specifically delivered to the tumor and not to normal tissues. Targeted nanoparticles have shown the potential to deliver the anticancer drugs to cancer cells selectively and to overcome unexpected cytotoxicity and limited efficacy of the chemotherapy caused by the unselective delivery to the normal cells. In our study a novel nanoparticle (HPLN) was used for the treatment of childhood ALL and Ewing's sarcoma. AntiCD19 and antiCD99 antibodies were used for targeting of ALL and Ewing tumor, respectively. These tumor specific HPLNs effectively inhibit tumor growth in a murine model. Removal of targeting antibody or drug eliminates the antitumor effects, which proves this anticancer effect of HPLN is very specific to the target cancer cells and dependent upon drug. No abnormalities in liver and kidney function tests, complete blood counts or pathology of major organs are observed from tail-vein administrations. Theses targeted HPLNs showed much better cytotoxicity over a conventional untargeted PEG-liposomal Doxorubicin formulation (Doxil®). Additionally the targeted HPLN could be found in the tumor cells in a murine model. In conclusion, we have found the safe and efficient targeted HPLN delivery system of anticancer drugs to childhood ALL and Ewing's Sarcoma.

Citation Format: Hyunggyoo Kang, Violette Shahbazian, Amanda Schafenacker, Jon Nagy, Timothy Triche. Development of selective therapy of childhood ALL and Ewing's sarcoma using targeted-hybrid polymerized liposomal nanoparticles (HPLN). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5424. doi:10.1158/1538-7445.AM2014-5424
Abstract 5450: Screening more than 60 human SCLC lines with approved and investigational agents indicates complex patterns of response: Identification of HSP90 and HDACs as potential targets
Authors: Evans David M. , Delosh Rene , Laudeman Julie , Ogle Chad , Reinhart Russell , Selby Michael , Silvers Thomas , Connelly John , Monks Anne , Polley Eric , Kaur Gurmeet , Morris Joel , Teicher Beverly
Published: May 2015

Small cell lung cancer (SCLC) is an aggressive cancer with a 5-year survival rate of <5%. While initially responsive to treatments with platinum agents, topoisomerase inhibitors or methotrexate, the tumors frequently recur after chemotherapy. To identify whether approved small molecule drugs or investigational agents may have unexpected effects in SCLC lines, we undertook a systematic large-scale screen with >500 compounds against > 60 well characterized SCLC cell lines in culture. Cells were exposed to 101 Approved Oncology Drugs (AOD) and 433 Investigational Agents. By evaluating compounds at 9 concentrations (10uM to 1.5nM), using cell viability 96h post drug exposure as the endpoint (Cell Titer Glo), we were able to obtain concentration response curves and IC50 values for the compounds and rank activity of these agents. In parallel studies, using Affymetrix exon ST1 arrays and miRNA profiling, we examined these same cell lines for differences in gene expression patterns that may correlate with sensitivity or resistance to select agents in the screen. The Myc oncogene (cMyc, LMyc, or nMyc) is over-expressed in about 40% of SCLC lines. Surprisingly, early analyses of the SCLC screen data have been unable to correlate high Myc expression with response to drugs or investigational agents (there is a trend with bromodomain inhibitors). The large majority of SCLC lines were sensitive to compounds against select target classes (e.g. HSP90 inhibitors and HDAC inhibitors). Examining HSP70 and HSP90 levels by Western blot suggested a slight reduction in HSP90 levels in cells resistant to the HSP90 inhibitor Ganetespib with no change in HSP70 levels. Some inhibitors against these targets showed broader cell activity than others. We are currently determining whether such differential drug sensitivity is correlated with specific changes in gene expression patterns in these cells. Further data analyses from the screen combined with genomic profiling of the cells will be presented.

Funded by NCI Contract No. HHSN261200800001E.

Citation Format: David M. Evans, Rene Delosh, Julie Laudeman, Chad Ogle, Russell Reinhart, Michael Selby, Thomas Silvers, John Connelly, Anne Monks, Eric Polley, Gurmeet Kaur, Joel Morris, Beverly Teicher. Screening more than 60 human SCLC lines with approved and investigational agents indicates complex patterns of response: Identification of HSP90 and HDACs as potential targets. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5450. doi:10.1158/1538-7445.AM2014-5450
Abstract 5461: The role of gene body cytosine modifications in MGMT expression and sensitivity to temozolomide
Authors: Moen Erika L. , Stark Amy L. , Zhang Wei , Dolan M. Eileen , Godley Lucy A.
Published: May 2015

The goal of precision medicine is to use patient-specific markers to design individualized treatment strategies. Promoter methylation of O6-methylguanine-DNA methyltransferase (MGMT), which encodes for the DNA repair protein MGMT, has been shown to predict glioblastoma patient survival after treatment with temozolomide. Unfortunately, there is no approved therapeutic alternative for patients whose tumors have an unmethylated MGMT promoter and are unlikely to respond to temozolomide treatment. Promoter methylation status of MGMT is used to predict expression levels of MGMT, despite some observed discordance between promoter methylation and protein levels. We hypothesized that incorporation of MGMT gene body cytosine modification levels in models of temozolomide response may lead to better prediction of MGMT expression levels and, more importantly, improved methods of prediction for glioblastoma patient response to temozolomide. Using 91 human glioblastoma samples from The Cancer Genome Atlas, we observed significant variation in MGMT expression levels in patients with an unmethylated promoter, with higher levels of gene body cytosine modification correlating with higher gene expression levels. Furthermore, inducing hypomethylation across the MGMT gene body with decitabine resulted in decreased levels of MGMT gene expression in lymphoblastoid and glioblastoma cell lines. These data indicate an important functional role for gene body cytosine modifications in maintaining gene expression levels. We reasoned that the decrease in MGMT expression induced by decitabine might render resistant glioblastoma cell lines more sensitive to temozolomide. Indeed, MGMT-expressing glioblastoma cell lines pre-treated with decitabine became significantly more sensitive to temozolomide-induced cytotoxicity. Overall, our results demonstrate a functional role for gene body cytosine modification in regulating gene expression of MGMT and suggest that patients with an unmethylated MGMT promoter could benefit from pre-treatment with decitabine to increase tumor sensitivity to temozolomide.

Citation Format: Erika L. Moen, Amy L. Stark, Wei Zhang, M. Eileen Dolan, Lucy A. Godley. The role of gene body cytosine modifications in MGMT expression and sensitivity to temozolomide. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5461. doi:10.1158/1538-7445.AM2014-5461
Abstract 547: Ethnic differences in CYP19A1 intronic SNPs and haplotype distributions among African American and Caucasian populations
Authors: Starlard-Davenport Athena , Penney Rosalind B. , Dhakal Ishwori , Kadlubar Susan
Published: May 2015

Ethnicity and gender variability in estrogen metabolism is an important consideration for assessing cancer risk and therapeutic efficacy in clinical medicine. Aromatase, encoded by the CYP19A1 gene, is a key enzyme that facilitates the bioconversion of estrogens from androgens. Single nucleotide polymorphisms (SNPs) of CYP19A1 influence the expression and activity of the enzyme and may also confer susceptibility to estrogen-dependent diseases and/or modulate the genotype-phenotype relationship among certain ethnic groups. In the present study, we evaluated SNPs within the intron region of the CYP19A1 gene and determined the allele and genotype frequencies of ten functionally relevant, tagged CYP19A1 SNPs in a total of 407 healthy African American (AA) and Caucasian (CA) subjects from Arkansas using Taqman SNP assays. The observed frequencies of the CYP19A1 minor alleles for the SNPs rs10459592 (T), rs12591359 (A), rs12908960 (A), rs11856927 (G), rs749292 (A), rs2470152 (A), rs1902584 (T), rs2470144 (T), rs1961177 (T), and rs6493497 (T) are 49.3, 39.2, 37.3, 43.5, 50, 48.7, 12, 38, 22, and 17, respectively. Gender-specific assessment showed significant differences in the genotype frequency for only rs1902584; however, significant inter-ethnic variability between the two groups was detected in the distribution of the majority of the CYP19A1 variants, including rs10459592 (p <0.001), rs12908960 (p<0.001), rs1902584 (p = 0.0157), rs2470144 (p<0.001), rs1961177 (p<0.001), and rs6493497 (p=0.0029). Haplotype analysis identified 3 CYP19A1 SNPs (rs10459592, rs12591359, rs12908960) that were in strong linkage disequilibrium (LD) and resulted in one LD block. In addition, CYP19A1 mRNA expression tended to be lower among subjects who were either homozygous or heterozygous for the CYP19A1 minor allele compared to those homozygous for the common allele, except for rs12591359, rs2470144, and rs1961177. In summary, our results provide evidence of ethnic differences in the frequency of CYP19A1 intronic SNPs between African American and Caucasian populations, suggesting that contributions of CYP19A1 SNPs in multiethnic epidemiological studies should be considered for translation of pharmacogenetics of aromatase inhibitors and for accessing risk of estrogen-dependent diseases across ethnic groups.

Citation Format: Athena Starlard-Davenport, Rosalind B. Penney, Ishwori Dhakal, Susan Kadlubar. Ethnic differences in CYP19A1 intronic SNPs and haplotype distributions among African American and Caucasian populations. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 547. doi:10.1158/1538-7445.AM2014-547
Abstract 5472: Systems pharmacogenomics approach identifies synergistic molecular action of combined MTOR/HDAC inhibition on MYC
Authors: Gamache Benjamin J. , Simmons John K. , Michalowski Aleksandra , Patel Jyoti , Zhang Ke , Zhang Shuling , DuBois Wendy , Zingone Adriana , Kuehl Michael , Huang Jing , Landgren Ola , Mock Beverly
Published: May 2015

Multiple myeloma (MM) and murine plasmacytoma (PCT) are rare mature B-lymphoid malignancies. Allelic variants of Mtor and Cdkn2a affect susceptibility to PCT, and functional alterations in the PI3K/MTOR and CYCLIN/CDK/CDKI/RB (RB) pathways are common to both malignancies. We found that combining sirolimus (rapamycin), an inhibitor of mechanistic target of rapamycin (MTOR), with entinostat (MS-275), a selective class I histone deacytlase (HDAC) inhibitor, was synergistic in controlling 90% of tested cell lines derived from B cell malignancies in vitro, effective in limiting xenograft growth in vivo, and diminished cellular viability in ex vivo patient samples. Similarly, the combination reduced tumor burden and volume and increased survival in a long-term, in-vivo study in C.B6-Bcl2l1 mice. To examine the core synergistic consequence of combining entinostat with sirolimus, an integrated, systems-level approach was used. Weighted gene co-expression analysis (WGCNA) of GEP data from MM cells treated individually and in combination was used to identify a distinct module of 126 genes cooperatively affected by both drugs. Of the cooperatively affected genes, 37 were found to be differentially expressed in MM and predictive of survival (p<0.01). Ingenuity upstream analysis identified MYC as a potential core regulator of the synergistic transcriptional response. MYC protein, but not mRNA, decreased in response to the drug combination when examined by Western blot and NanoString analyses, respectively. Using tet-off, MYC-inducible transformed P493 cells, the necessity of MYC for the drop in cellular viability and response of the gene signature to the combination was evident. Using the translational and proteasomal inhibitors, cycloheximide and MG132, respectively, it was determined that MYC protein half-life decreased with the combination, largely due to proteasomal degradation. Utilizing a systems-level approach and biological filters, an alternative route to MYC inhibition was determined. Biologically relevant, this methodology can be used to define the molecular underpinnings of drug combinations, applicable to many diseases.

Citation Format: Benjamin J. Gamache, John K. Simmons, Aleksandra Michalowski, Jyoti Patel, Ke Zhang, Shuling Zhang, Wendy DuBois, Adriana Zingone, Michael Kuehl, Jing Huang, Ola Landgren, Beverly Mock. Systems pharmacogenomics approach identifies synergistic molecular action of combined MTOR/HDAC inhibition on MYC. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5472. doi:10.1158/1538-7445.AM2014-5472
Abstract 5487: The requirements for dasatinib sensitivity in human melanoma cell lines
Authors: Vachtenheim Jiri , Réda Jiri , Ondrušová Lubica , Zakova Petra
Published: May 2015

Mutated BRAF oncogene, which fuels unregulated MAPK pathway in most melanomas, can be targeted by a small-molecule drug vemurafenib. However, most of patients develop an acquired resistance during treatment or have an intrinsic resistance to this drug. Nonreceptor SRC tyrosine kinase is deregulated in most cancer cell types and can be efficiently inhibited by a small-molecule inhibitor dasatinib, an anticancer drug which is already used for the treatment of some cancers and is in final clinical trials for other tumor types. Although SRC does not have its own canonical pathway, it is capable of activating and augmenting different signaling routes in cancer cells. We found that melanoma tumor cell lines analysed up to date are generally resistant to dasatinib. The exception to this rule was Hbl, a very sensitive cell line whose cells were completely killed by a 10 nM of dasatinib in a few days. The difference in resistance of melanoma cell lines to dasatinib did not depend on primary versus metastatic cell origin or the presence of BRAF or NRAS mutations. Instead, the dasatinib sensitivity was dependent on its ability to inhibit completely both the MAPK and AKT/mTOR signaling pathways. This inhibition was at least as prominent as the inhibition by specific inhibitors of the two pathways. SRC has been reported previously to have links to this signaling pathways with the capacity to inhibit them in some cell types. Moreover, extensive cross-talk exists between the two pathways. Similar results were observed in several other cell lines derived mostly from lung and colorectal cancers. Our data indicate that the singular therapy of melanoma by dasatinib only would bring no benefit to patients, except for the cases (probably rare) where dasatinib strongly blocks both MAPK and AKT signaling pathways in tumor cells. More molecular knowledge about the effects of the powerful anticancer drug dasatinib is required in order to be used for the treatment of melanoma. This work was supported by grant IGA no. NT/14005-3 from the Ministry of Health (Czech Rep.) and by Institutional research project PRVOUK-P25/LF1/2.

Citation Format: Jiri Vachtenheim, Jiri Réda, Lubica Ondrušová, Petra Zakova. The requirements for dasatinib sensitivity in human melanoma cell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5487. doi:10.1158/1538-7445.AM2014-5487
Abstract 5494: The effect of honokiol combined with PPARγ agonists in regulation of cell growth and migration in human hepatoma cells
Authors: Chi Chin-Wen , Hsu Hui-Tzu
Published: May 2015

Hepatocellular carcinoma (HCC) is one of the malignant cancers worldwide. At present, surgical resection is the best treatment for HCC. Despite some other options such as chemotherapy and radiotherapy, recurrence and metastasis are the major causes of increased mortality. It has been reported honokiol, a natural biphenolic compound, exerts inhibitory effects on the growth and migration of hepatoma cells. Most recently, it was found that honokiol functions as not only an RXR agonist but also a PPARγ agonist, and is capable of potentiating the activation of PPARγ in the presence of PPARγ agonist rosiglitazone in 3T3-L1 adipocytes and HLE human hepatoma cells. Moreover, PPARγ agonists exhibited inhibitory role in cell growth and migration in various cancers through PPARγ-dependent and -independent pathway. However, the combination effect and the molecular mechanism of cotreatment with honokiol and PPARγ agonists are still unclear in hepatoma cells. In this study, Hep3B, Mahlavu, and SK-Hep1 human hepatoma cells were treated with honokiol and/or PPARγ agonists. Honokiol and PPARγ agonists rosiglitazone and troglitazone inhibited cell growth in hepatoma cells by surforhodamine B assay, respectively. Moreover, cotreatment with honokiol and PPARγ agonist showed additive effect in cell growth inhibition. Furthermore, retrovirus-mediated PPARγ overexpression in SK-Hep1 cells resulted in higher sensitivity to honokiol treatment in cell growth inhibition compared to vector control. Additionally, PPARγ agonists rosiglitazone and troglitazone inhibited cell migration in Hep3B cells by wound healing and transwell assays. These results together suggest that honokiol combined with PPARγ agonist had additive effect in cell growth inhibition and migration of hepatoma cells. The molecular mechanism and potential application of this combination for treatment of hepatoma will be presented.

Citation Format: Chin-Wen Chi, Hui-Tzu Hsu. The effect of honokiol combined with PPARγ agonists in regulation of cell growth and migration in human hepatoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5494. doi:10.1158/1538-7445.AM2014-5494
Abstract 5500: Sensitivity of metastatic breast cancer (4T1) cells to apoptotic effect by Lactobacillus kefiri P-IF via a mechanism that involves hole piercing in cancer cells
Authors: Ghoneum Mamdooh H.
Published: May 2015

Objective: Metastasis, the spread of cancer from its origin, is primarily responsible for the majority of deaths from human solid-organ cancer. Lactobacillus kefiri P-IF, a freeze-dried form of heat-killed L. kefiri, is a specific strain of lactic acid bacteria that has a unique DNA sequence and PET scans showing a 99.6% homology with regular kefiris. In the current study, we evaluate the apoptotic effect of L. kefiri P-IF on metastatic breast cancer (MBC) cells.

Materials and Methods: 4T1, murine MBC, were cultured with different concentrations of L.kefiri P-IF (0, 1.25, 2.5 and 5 mg/ml) and the apoptotic response was assessed by propidium iodide assay and trypan blue exclusion test. Changes in mitochondrial membrane potential (MMP) were monitored by flow cytometry. Changes in percentages of cancer cells bearing holes were examined by Giemsa-stained cytospin preparation under a light microscope.

Results: L.kefiri P-IF induced apoptosis in 4T1 cells. Incubation with L. Kefiri P-IF at 5 mg/ml induced apoptosis in 91% of 4T1 cells compared to 7% apoptosis for control untreated cells. A significant apoptotic effect by L.kefiri P-IF was detected as early as 90 min post exposure with cancer cells, showing 25 fold increase in apoptotic non-adherent cells as compared to control untreated cells. The apoptotic effect was further increased 30 to 75 fold at 24 and 48 hours, respectively. The induction of apoptosis by L.kefiri P-IF was associated with significant decrease in the polarization of MMP and an increase in the percentages of adherent cells bearing multiple holes, suggesting that the mechanism by which L.kefiri P-IF induces its apoptotic effect involves piercing holes in cancer cells. Thes holes are shown to vary in circumference and depth. Control untreated adherent cells showed 40% cells with no holes and 43% cells bearing more than 5 holes. In contrast, L.kefiri P-IF treated adherent cells showed only 7% cells with no holes, while cells bearing more than 5 holes reached 87 %, this represents a 2 fold increase in cells with multiple holes over control cells.

Conclusion: These results suggest that L.kefiri P-IF exerts an apoptotic effect on MBC cells by a mechanism that involves the hole piercing in cancer cells, and may represent a new class of adjuvants for the treatment of metastatic breast cancer. L.kefiri P-IF was provided by Paitos Co., Ltd. Yokohama, Kanagawa, Japan.

Citation Format: Mamdooh H. Ghoneum. Sensitivity of metastatic breast cancer (4T1) cells to apoptotic effect by Lactobacillus kefiri P-IF via a mechanism that involves hole piercing in cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5500. doi:10.1158/1538-7445.AM2014-5500
Abstract 5502: Metrics other than potency reveal systematic variation in responses to cancer drugs
Authors: Fallahi-Sichani Mohammad , Honarnejad Saman , Heiser Laura M. , Gray Joe W. , Sorger Peter K.
Published: May 2015

Most analyses of cellular responses to anti-cancer drugs focus on variation in potency (e.g. GI50 or IC50) under the assumption that potency is the most important difference between effective and ineffective drugs or sensitive and resistant cells. We took a multi-parametric approach involving analysis of additional features such as maximum effect (Emax), the slope of the dose-response curve (Hill Slope; HS), and the area under the curve (AUC). We found that a subset of these parameters varies in a systematic manner with cell line and another subset with drug class. For cell cycle inhibitors, Emax generally correlates with cell proliferation rate but this is not always true: Emax ∼ 0 for S-phase specific drugs such as cisplatin, carboplatin and oxaliplatin across multiple cell lines. For drugs targeting the Akt/PI3K/mTOR pathway the slope of the dose-response curve is unusually shallow (HS << 1). Classical pharmacology has no ready explanation for this phenomenon but single-cell analysis showed that it correlated with significant and heritable cell-to-cell variability in the extent of target inhibition. We conclude that parameters other than potency should be considered in the comparative analysis of drug response, particularly at clinically relevant concentrations near and above IC50.

Citation Format: Mohammad Fallahi-Sichani, Saman Honarnejad, Laura M. Heiser, Joe W. Gray, Peter K. Sorger. Metrics other than potency reveal systematic variation in responses to cancer drugs. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5502. doi:10.1158/1538-7445.AM2014-5502
Abstract 5509: The role of WW domain-containing oxidoreductase in methotrexate-induced cell death in human squamous cell carcinoma
Authors: Hsu Li-Jin
Published: May 2015

Refractory cancer cells to initial chemotherapy in squamous cell carcinomas (SCC) may cause subsequent disease relapse and distant metastasis. We show that the susceptibility of SCC cancer cells to methotrexate (MTX) was associated with higher expression levels of tumor suppressor WW domain-containing oxidoreductase (designated WWOX, FOR or WOX1). Upregulation of WWOX/WOX1 expression by MTX treatment, accompanied by caspase activation and apoptotic cell death, was observed in MTX-sensitive SCC cell lines and tumor biopsies. Ectopically overexpressed WWOX/WOX1 sensitized MTX-resistant SCC-9 cells to MTX-induced apoptosis. Conversely, transient expression of a dominant negative mutant or an siRNA construct targeting WWOX/WOX1 suppressed MTX-mediated cell death in SCC-15 cells. Interestingly, following MTX treatment, significant downregulation of autophagy-related Beclin-1, Atg12-Atg5 and LC3-II protein expression and autophagosome formation was observed in MTX-sensitive SCC-15 cells, while autophagy remained robust in MTX-resistant SCC-9 cells. Increased phosphorylation of mTOR and its downstream substrate p70 S6 kinase (p70S6K) was detected in MTX-treated SCC-15 cells, whereas MTX suppressed the autophagy-inhibitory mTOR signaling in SCC-9 cells. We determined that activation of mTOR and p70S6K by MTX treatment in SCC-15 cells was mediated by WWOX/WOX1. Ectopic overexpression of WWOX/WOX1 in SCC cells induced significant downregulation of Beclin-1, Atg12-Atg5 and LC3-II protein expression, and MTX treatment exacerbated their diminution. Suppression of WWOX/WOX1 by lentiviral shRNA prevented MTX-induced reduction in LC3-II expression in SCC-15 cells. Our findings indicate that WWOX/WOX1 renders SCC cells susceptible to MTX-induced apoptosis by dampening autophagy, and the failure to induce WWOX/WOX1 expression leads to chemotherapeutic drug resistance.

Note: This abstract was not presented at the meeting.

Citation Format: Li-Jin Hsu. The role of WW domain-containing oxidoreductase in methotrexate-induced cell death in human squamous cell carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5509. doi:10.1158/1538-7445.AM2014-5509
Abstract 5514: Metformin sensitizes anticancer effect of dasatinib through AMPK-dependent ER stress in head and neck squamous cell carcinoma cells
Authors: Lin Yu-Chin , Wu Meng-Hsuan , Wei Tzu-Tang , Lin Yun-Chieh , Chen Ching-Chow
Published: May 2015

Purpose: Head and neck squamous cell carcinoma (HNSCC) is an important endemic disease in Taiwan with aggressive course and dismal outcome. Dasatinib is a Bcr-bl and Src kinase inhibitor that has potential against HNSCC. We recently disclosed that EGFR degradation is critical for dasatinib-induced apoptosis. Here, we further demonstrate that AMPK-dependent ER stress is responsible for this effect.

Experimental design: Dasatinib-induced ER stress and AMPK activation was investigated in HNSCC cells including Ca9-22, HSC3, and SAS. The anti-cancer activity of dasatinib in combination with AMPK activator was examined in vitro and in vivo. EGFR expression and AMPK activation were correlated in human specimens.

Results: Dasatinib-induced ER stress was involved in dasatinib-induced EGFR degradation and apoptosis, and ER stress mediated EGFR degradation in a c-cbl-dependent manner. In addition, dasatinib-induced AMPK activation led to dasatinib-induced ER stress and EGFR degradation, and activation of AMPK might be due to ATP decrease through the up-regulation of pyruvate dehydrogenase kinase 4 (PDK4) induced by dasatinib. Furthermore, activation of AMPK by metformin potentiated dasatinib-induced anti-cancer effect in vitro and in vivo. The correlation of AMPK activation and EGFR expression was seen in HNSCC cells and human tumor specimens.

Conclusions: Our results disclose that AMPK-dependent ER stress plays a crucial role in anti-cancer effect of dasatinib on HNSCC and activation of AMPK might enhance dasatinib efficacy.

Note: This abstract was not presented at the meeting.

Citation Format: Yu-Chin Lin, Meng-Hsuan Wu, Tzu-Tang Wei, Yun-Chieh Lin, Ching-Chow Chen. Metformin sensitizes anticancer effect of dasatinib through AMPK-dependent ER stress in head and neck squamous cell carcinoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5514. doi:10.1158/1538-7445.AM2014-5514
Abstract 5518: BPM 31510 exposure alters fluidity and molecular organization of cancer cell membranes, influencing signaling and cell fate decisions
Authors: Kiebish Michael , Garg Sumit , Vishnudas Vivek , Gao Fei , Du Min , Dhavala Sirisha , Krumova Katerina , Rodriguez Leonardo , Luan Shen , Akmaev Viatcheslav R. , Sarangarajan Rangaprasad , Narain Niven R.
Published: May 2015

The dynamic state of membranes impinges on pathways critical for cancer cell survival or death while influencing cancer cell metabolism. Here in, we investigated the effects of BPM 31510, a proprietary ubidecarenone formulation, on temporal alterations in membrane adaptation, proteomic and lipidomic reorganization, initiation of key apoptotic signaling pathways, bioenergetic integration, as well as cell fate decision processes in in vitro models of representative cancers. This approach was harvested to decipher a systems wide understanding of BPM 31510's effects on various human cancer cell lines (prostate, pancreatic, skin, breast and ovarian ) as well as effect on representative control cell lines. BPM 31510 exposure in vitro resulted in a stochastic shift in membrane fluidity in various cancer cell lines. Global untargeted shotgun lipidomics and proteomics revealed selective lipidomic and protein shifts in a temporal manner across various cancer lines resultant from BPM 31510 exposure. Berg informatics suite comprising of Bayesian artificial intelligence systems engineering framework linked specific pivot lipid molecular species and proteins to the action of BPM 31510 based on dynamic time course experiments and biological endpoints including cellular metabolism and cell fate (apoptosis) across cancer cell lines. Thus, the data presented within demonstrate that BPM 31510 affects the cancer cell biomembrane structure, membrane lipid reorganization with potential to influence intracellular signaling, cell fate decision making processes and metabolism. The systems approach described within provides novel insight into the pleiotropic effects of BPM 31510 on cancer cells.

Citation Format: Michael Kiebish, Sumit Garg, Vivek Vishnudas, Fei Gao, Min Du, Sirisha Dhavala, Katerina Krumova, Leonardo Rodriguez, Shen Luan, Viatcheslav R. Akmaev, Rangaprasad Sarangarajan, Niven R. Narain. BPM 31510 exposure alters fluidity and molecular organization of cancer cell membranes, influencing signaling and cell fate decisions. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5518. doi:10.1158/1538-7445.AM2014-5518
Abstract 5541: Proteasome inhibitor synergizes with histone deacetylase inhibitor to trigger ROS- and ER stress-induced apoptosis of nasopharyngeal carcinoma independent of aggresome disruption
Authors: Chiang Alan K. , Hui Kwai Fung
Published: May 2015

Proteasome inhibitor and histone deacetylase inhibitor (HDACi) can synergistically induce apoptosis of cancer cells through aggresome disruption or induction of endoplasmic reticulum (ER) stress. We previously reported that suberoylanilide hydroxamic acid (SAHA), a pan-HDACi, and bortezomib, a proteasome inhibitor can synergistically induce apoptosis of nasopharyngeal carcinoma (NPC) cells through reactive oxygen species (ROS)-driven caspase-dependent mechanism. Here, we wish to investigate the role of aggresome disruption or ER stress in the process. We first tested the effect of bortezomib combining with a more specific HDACi, including MS-275, apicidin or romidepsin, on proliferation of NPC cells. Bortezomib could synergize with each of the specific HDACis to induce killing of the NPC cells. Strong apoptosis was demonstrated by the proteolytic cleavage of PARP and caspase-3, -8 and -9 as well as the high percentage of annexin V/propidium iodide (AV/PI)-positive NPC cells upon treatment with combination of bortezomib at 7.5 to 15 nM and romidepsin at 2.5 to 5 nM. Consistently, the apoptosis was ROS- and caspase-dependent. Interestingly, α-tubulin, a key substrate of histone deacetylase 6, was not acetylated, arguing against the involvement of aggresome disruption. In contrast, ER stress induction might be involved because ATF-4 and CHOP, which are markers of ER stress, were up-regulated by combined bortezomib/romidepsin and inhibition of caspase-4 could suppress the apoptosis. Furthermore, addition of ROS scavenger, N-acetyl-cysteine, suppressed the expression of ATF-4 and CHOP. We conclude that proteasome inhibitor can synergize with HDACi to trigger ROS- and ER stress-induced apoptosis of NPC cells, independent of aggresome disruption.

This project is funded by NPC Area of Excellence (AoE/M 06/08 Center for Nasopharyngeal Carcinoma Research), CRCG (#10401264) and Epstein-Barr virus research (# 20004525) grants of A.K.S. Chiang.

Citation Format: Alan K. Chiang, Kwai Fung Hui. Proteasome inhibitor synergizes with histone deacetylase inhibitor to trigger ROS- and ER stress-induced apoptosis of nasopharyngeal carcinoma independent of aggresome disruption. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5541. doi:10.1158/1538-7445.AM2014-5541
Abstract 5550: SNPs in UDP-glucuronosyltransferase1A4 (UGT1A4) and multidrug resistant protein (MRP) and their influence on anastrozole metabolism and disposition
Authors: Edavana Vineetha Koroth , Penney Rosalind , Borengasser Aiwei Yao- , Rogers Lora , Dhakal Ishwori , Williams Suzanne , Kadlubar Susan
Published: May 2015

Anastrozole is an aromatase inhibitor (AI) used as adjuvant therapy for breast cancer. Anastrozole belongs to the non-steroidal triazole-derivative group of AIsand is predominantly metabolized by Phase I oxidation followed by other Phase II reactions, including glucuronidation. Anastrozole is also subject to direct glucuronidation catalyzed by UDP-glucuronosyltransferase1A4 (UGT1A4). We have demonstrated a significant association between expression levels of the drug transporter genes MRP2 and MRP3 and anastrozole glucuronidation. We hypothesized that genetic variability in UGT1A4 and MRPs could influence anastrozole metabolism and disposition.

Using normal human liver samples obtained from the Cooperative Human Tissue Network, we analyzed the correlation of UGT1A4, MRP2 and MRP3 mRNA and protein expression levels with anastrozole glucuronidation. UGT1A4 and MRP2 mRNA and protein expression levels were significantly correlated with anastrozole gucuronidation (p<0.05). Further, we examined the correlation of UGT1A4 and MRP2 SNPs with anastrozole glucuronidation. We observed a significant correlation (p<0.05) of UGT1A4 promoter SNPs (-163G>A, -217T>G, -219C>T) and MRP2 SNPs (3563T>A, 4430C>T and -24C>T) with anastrozole glucuronidation (Table 1).

These data indicate that UGT1A4 and MRP2 SNPs could interact to influence anastrozole metabolism and disposition. Pharmacogenetic studies are needed to elucidate the role of UGT1A4 and MRP2 SNPs in the inter-individual variability in anastrozole metabolism and disposition, as well as the overall efficacy of anastrozole treatment.

Table 1

SNPUGT_mRNAMRP2 mRNAMRP3 mRNAAna-gluc-Nm/uL/ugUGT1A4 -36(G/A)0.260.130.560.26UGT1A4 -163(G/A)<0.00010.030.64<0.0001UGT1A4-217(T/G)0.0180.0570.810.01UGT1A4-219(C/T)<0.00010.010.05<0.0001MRP2 3563(T/A)0.051<0.00010.030.033MRP2 4544(G/A)0.15<0.0010.720.14MRP2 1249(G/A)0.25<0.0110.430.34MRP2 2366(C/T)0.12<0.00010.180.14MRP2 4430(C/T)0.02<0.00020.0610.01MRP2 -24(C/T)0.01<0.00010.0010.02MRP3 -1767 (G/A)0.780.690.0010.93MRP3 -211 (C/T)0.860.55<0.00010.81

Citation Format: Vineetha Koroth Edavana, Rosalind Penney, Aiwei Yao- Borengasser, Lora Rogers, Ishwori Dhakal, Suzanne Williams, Susan Kadlubar. SNPs in UDP-glucuronosyltransferase1A4 (UGT1A4) and multidrug resistant protein (MRP) and their influence on anastrozole metabolism and disposition. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5550. doi:10.1158/1538-7445.AM2014-5550
Abstract 557: Noninvasive analysis of acquired resistance to EGFR-TKI
Authors: Kimura Hideharu , Nishio Makoto , Daito Tsutomu , Nishio Kazuto
Published: May 2015

BACKGROUND

Epidermal growth factor receptor (EGFR) T790M mutation is associated with EGFR tyrosine kinase inhibitors (EGFR-TKIs) resistance in non-small cell lung cancer (NSCLC). However, the tissue availability limits the genotyping of EGFR T790M mutation in the clinical setting. The aims of this study are to develop a blood-based, non-invasive approach to detect the EGFRT790M mutation in advanced NSCLC patients. Additionally, plasma concentrations of HGF, MET and amphiregulin which are also resistant factors of EGFR-TKIs

EXPERIMENTAL DESIGN

Plasma sample were collected from NSCLC patients with activating EGFR mutations, who had resistant to EGFR-TKIs treatment. EGFR T790M mutations were detected using droplet-digital PCR (ddPCR) system from plasma DNA at resistance to EGFR-TKI. Plasma concentrations of HGF, soluble MET (sMET) and amphiregulin were determined using enzyme-linked immunosorbent assay. The relationships between the EGFR T790M mutation status and the plasma concentrations, progression-free survival (PFS) overall survival (OS) were analyzed.

RESULTS

Twenty-one (35%) of the patients had EGFR T790M mutation in plasma DNA using ddPCR system. The levels amphiregulin tended to be increased at the resistance in the patients with EGFR T790M mutation. The PFS and OS of the patients with EGFR T790M mutation was significantly shorter than that of the patients without EGFR T790M mutation (P =0.03 and 0.04). The PFS of the patients who had high amphiregulin at the resistance and the OS of the patients who had high amphiregulin at pre-treatment were shorter than these of t low amphiregulin (P = 0.05 and 0.05)

CONCLUSIONS

The ddPCR system is a detectable method for determining the plasma EGFR T790M mutation status. The combination of EGFR T790M mutation status by ddPCR and the amphiregulin levels may aid in monitoring drug resistance and in predicting a prognosis.

Citation Format: Hideharu Kimura, Makoto Nishio, Tsutomu Daito, Kazuto Nishio. Noninvasive analysis of acquired resistance to EGFR-TKI. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 557. doi:10.1158/1538-7445.AM2014-557
Abstract 5572: Auto-analysis of immunohistochemical findings and one-day instant quality fluorescence in situ hybridization increase quality of breast cancer therapy
Authors: Taniyama Daiki
Published: May 2015

Background:Currently, the therapeutic strategy for a breast cancer patient is designed according to his/her histopathological, immunohistochemical and molecular findings. These findings are obtained through the collected efforts of many individual pathologists or medical technologists and are thus limited by intra-observer error and potentially subjective decision-making. The assessment of immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) is demanded to be prompt, objective, and reproducible. In our institute, the authors are utilizing the whole slide imaging system (NanoZoomer 2.0-HT, Hamamatsu photonics, Japan) and a software for image analysis (Genie, Vista, CA), specifically for an auto-analysis of IHC. We succeeded in gaining objective and highly reproducible results. On the other hand, current FISH technique is time-consuming and takes two days to complete due to the overnight incubation required to obtain proper hybridization result. The authors tried to compare the results with current FISH (cFISH) and one-day Instant Quality FISH (IQFISH) for human epidermal growth factor receptor 2 (HER2).

Methods: Auto-analysis arm. Twenty-five breast cancer specimens were examined for IHC of estrogen receptor (ER), progesterone receptor (PgR) HER2, Topoisomerase (Topo) II alpha, and Ki-67, and the results were compared by ocular observation and auto-analysis. Fifty-one cancer specimens were compared in terms of IHC and cFISH of HER2.IQFISH arm. Thirty-four biopsy samples from pre-therapeutic breast cancers (29 primary invasive ductal carcinomas and five metastatic cancers) were examined and the results of cFISH and IQFISH were compared.

Results: Auto-analysis arm. For all antibodies, expect for HER2, concordant results were obtained in 100% of 24 ER positive cases. Ki-67 index (r=0.96) and TopoIIalpha index (r=0.95) also showed a significant correlation (p<0.001). For cHER2, all four specimens with Hercep-score 2 by ocular observation but 1 by auto-analysis revealed no HER2 gene amplification. IQFISH arm. IQFISH (r=0.66) showed a significant correlation (p<0.0001) with cFISH. Both auto-analysis and IQFISH reduced substantially the time for analysis.

Conclusion: Well-organized auto-analysis is more likely to result in an objective observation and provide a means by which to standardize the methods of IHC in breast cancer. IQFISH may contribute to an earlier decision regarding therapeutic strategy for a breast cancer.

Citation Format: Daiki Taniyama. Auto-analysis of immunohistochemical findings and one-day instant quality fluorescence in situ hybridization increase quality of breast cancer therapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5572. doi:10.1158/1538-7445.AM2014-5572
Abstract 5574: Gli2 protein and the AR operational switch to the castration resistant prostate cancer transcription program
Authors: Li Na , Buttyan Ralph , Truong Sarah , Yu Yue , Chen Mengqian
Published: May 2015

Gli proteins are transcription factors that mediate Hedgehog (HH) signaling in cells. Previously, we reported that Gli2 binds to the androgen receptor (AR) protein in prostate cancer (PCa) cells and further upregulates expression of genes under AR control. This “co-activator” effect allows the growth of Gli2 overexpressing LNCaP cells in androgen-depleted medium, mimicking the behavior of castrate resistant variants of PCa. We report here our success in localizing the specific binding domains between Gli2 and AR proteins. Outcomes of GST-pulldown and co-immunoprecipitation studies showed that Gli2 binds to AR via a limited domain (aa628-aa897) within the C-terminal region and this recognizes the tau5/AF5 domain (aa 392-558) within the N-terminal region of the AR protein. Because tau5/AF5 is conserved in truncated (splice variant) ARs, we also showed that Gli2 recognizes and co-activates the transcriptional activity of a truncated variant AR (AR-V7). To further define Gli2 regulatory functions on AR transcriptional activity in CRPC, we overexpressed Gli2ΔN (a constitutive-active form of Gli2) in LNCaP-AI (androgen-independent) cells and examined its effects on AR target gene expressions. Surprisingly, we found that Gli2Δ overexpression coincided with significant downregulated expression of genes considered “traditional” AR targets (i.e., KLK3 and KLK2), while increasing the expression of M-phase check-point genes, such as UBE2C, CDK1 and CDC20. In contrast, treatment of unmodified LNCaP-AI cells with the Gli-inhibitor, GANT61, significantly increased expression of KLK2 and KLK3 while downregulating UBE2C, CDC20 and CDK1. Our outcomes now imply that Gli2 differentially affects the AR transcriptional program in androgen-dependent (LNCaP) vs androgen-independent (LNCaP-AI) cells. In androgen-dependent cells, Gli2 co-activates expression of the traditional AR target genes while suppressing expression of genes involved in the CRPC transcriptional program whereas in androgen-independent cells, Gli2 co-activates expression of CRPC program genes while downregulating expression of traditional AR target genes. This dichotomy suggests that Gli2 participates in the decisions through which AR transcriptional activity is redirected in castration resistant disease. Supported by the DOD PCRP (W81XH-10-1-0493, to RB)

Citation Format: Na Li, Ralph Buttyan, Sarah Truong, Yue Yu, Mengqian Chen. Gli2 protein and the AR operational switch to the castration resistant prostate cancer transcription program. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5574. doi:10.1158/1538-7445.AM2014-5574