bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 3341: Chronic TNFα treatment enhances cancer stem cell-like phenotype via Notch1 activation in oral squamous cell carcinoma cells
Authors: Lee Sung Hee , Kim Reuben , Kang Mo , Park No-Hee , Shin Ki-Hyuk
Published: August 2012

Although there is an increasing evidence of chronic inflammation-associated tumorigenesis, the molecular and cellular mechanisms linking chronic inflammation to tumorigenesis have not yet been fully understood. Recent studies have uncovered and validated the pathophysiological role of self-renewing cells, named cancer stem cells (CSC; also called tumor-initiating cells), in long-term sustenance of cancers. In this study, we investigated the effect of chronic inflammation on CSC phenotype of oral squamous cell carcinoma cells (OSCC). We treated OSCC cell lines with tumor necrosis factor alpha (TNFα), a major proinflammatory cytokine, for extended periods and examined the effect of chronic TNFα on CSC characteristics, i.e., undifferentiated tumor sphere forming ability, stem cell-associated genes expression and chemo-radioresistance. Chronic treatment of OSCC with TNFα enhanced CSC phenotype, which is shown by increased tumor sphere forming ability, greatly increased tumorigenicity and chemo-radioresistance, and increased expression of stemness-related genes. Moreover, activation of Notch1 signaling was detected in the TNFα treated cell, and suppression of Notch1 signaling inhibited CSC phenotype. Furthermore, we demonstrated that inhibition of Hes-1, the downstream target of Notch1, led to suppression of CSC phenotype. Taken together, the data suggest that proinflammatory cytokine exposure can generate or/and enrich OSCC CSC population, in part, by activation of the Notch1 signaling pathway.

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 3341. doi:1538-7445.AM2012-3341
Abstract 3347: A proneural signature profile predicts response to Notch inhibition in glioma stem cells
Authors: Saito Norihiko , Fu Jun , Yao Jun , Verhaak Roel GW , Koul Dimpy , Yung W.K. Alfred
Published: August 2012

The Cancer Genome Atlas Network described genomic abnormalities and gene expression-based molecular subtypes of GBM that showed a strong relationship between subtypes, genomic alterations and different neural lineages. Future studies are required to elucidate the intricate relationship between tumor subtypes and treatment response. We have thus embarked on a comprehensive effort to detecting expression signatures that are associated with response to the therapy and these signatures may allow prospective selection of patients with high likelihood of responding to therapy. Notch signaling pathway is an evolutionarily conserved pathway that plays an important role in multiple cellular and developmental processes including cell fate decision, differentiation, proliferation, survival, angiogenesis and migration. Recent studies indicate that the Notch signaling pathway regulates normal stem cells in the brain, and glioma stem Cells (GSCs) with high Notch activity. We investigated the effects of Notch pathway inhibition on GSCs growth using commercially available inhibitors. Drug cytotoxicity test on 16 GSCs show differential growth response to Notch inhibitors stratifying GSCs into two groups: responders (6 cell lines) vs non-responders (10 cell lines). Gene expression clustering identified a responder gene signature enriched in 1: proneural genes such as Olig2, Sox-9, NKX2-2, and 2: Notch signaling component such as Notch-1, Notch-3, Hes-3 and Hes-5. These signature were validated by western blot analysis. Treatment with Notch inhibitors reduced neurosphere formation in vitro accompanied with attenuated Notch intracellular domain (NICD), Hes-1, Hes-3, and Hes-5. In addition, the expression of nestin-the stem cell marker was reduced and an increased expression of lineage differentiation markers TuJ1 and GFAP was observed following Notch inhibition. In conclusion, we have identified a responder signature for a group of glioma stem cells that can be targeted by Notch inhibitors and this may allow the selection of patients with high likelihood of responding to this therapy.

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 3347. doi:1538-7445.AM2012-3347
Abstract 3359: Salinomycin reduces stem cell properties and induces apoptosis in mammary epithelial cell
Authors: sook An Hyun , Kang Han-Na , Kang Myoung-Hee , Kim Jung-Lim , Kim Jun-Suk , Seo Jea-Hong
Published: August 2012

Tumor initiating cells or cancer stem cells (CSCs) were characterized as a unique subpopulation with stem cell features in many types of cancer. Although there has been a number of studies on breast cancer stem cells, inhibitory mechanisms of tumor initiation, progression, and resistance to therapy are unknown. Salinomycin is a chemical isolated from Streptomyces albus and a potassium ionophore. It has been used for many years to control coccidiosis. Recently, salinomycin has been reported to act as selective breast cancer stem cell inhibitor because of its property of reducing the cancer stem cell and inducing the apoptosis in cancer cell. Thus, we investigated the anti-cancer property of salinomycin in mouse mammary epithelial cell. With CDμgeo (mouse mammary epithelial cell), MTT assay was used to confirm cell viability after salinomycin treatment (0, 0.5, 1, 2, 5, 10 μm/ml) upon anchorage-dependent state. We observed that salinomycin reduced the cell proliferation dose-dependently. Also, mammosphere formation assay was performed to observe stem cell-like property after salinomycin treatment in anchorage-independent state. We confirmed salinomycin reduced the number and the size of mammosphere in 72, 144, and 216 hours. We performed salinomycin pre-treatment (0, 0.5, 1, 2, 5 μm/ml) for 12-48 hours upon anchorage-dependent state. Results by western blotting revealed that salinomycin promoted apoptosis of mouse mammary epithelial cells by activating both caspase-3 and -9 and inducing PARP cleavage. To confirm the reduction of the side population level, we performed FACS analysis using CD49+, CD29+, and CD24+ markers. Based on our findings, we concluded that anti-cancer effect of salinomycin reduced stemness and induced apoptosis in mouse mammary epithelial cell.

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 3359. doi:1538-7445.AM2012-3359
Abstract 3360: The hedgehog pathway inhibitor GDC-0449 alters intracellular Ca2+-homeostasis and inhibits cell growth in cisplatin-resistant lung cancer cells
Authors: Tian Fei , Huber Rudolf Maria , Schrödl Kathrin , Tufman Amanda , Kiefl Rosemarie , Bergner Albrecht
Published: August 2012

Cisplatin-resistance is an important issue in lung cancer. The hedgehog signaling pathway (Hh) has been shown to be activated in cancer. GDC-0449 is a low-molecular Hh pathway inhibitor that binds to and inhibits Hh pathway receptor SMO. It is the first systemic SMO-inhibitor that has entered clinical trials. Recently, we could show that GDC-0449 is effective in lung cancer cell lines and that combination with cisplatin gives an additional effect. However, no data on the effect of GDC-0449 on cisplatin-resistant lung cancer cells are available. We aimed at investigating if the hedgehog pathway inhibitor GDC-0449 is effective in cisplatin-resistant cells and if it alters the intracellular Ca2+-homeostasis. The cytoplasmatic ([Ca2+]cyto) and endoplasmatic ([Ca2+]ER) Ca2+-concentration of HCC (adeno carcinoma of the lung) and H1339 (small cell lung carcinoma) cells was measured with the calcium indicator dye Fura-2 AM. The expression of the inositol-1,4,5-trisphosphate receptor (IP3R) and Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) were analyzed using Western Blot analysis. GDC-0449 inhibited cell growth in cisplatin-naïve and -resistant cells. In both cell types, GDC-0449 increased [Ca2+]cyto and reduced endoplasmatic [Ca2+]ER. Cisplatin failed to considerably alter the Ca2+-homeostasis in resistant cells. The effects of GDC-0449 on the intracellular Ca2+-homeostasis were not mediated by an altered expression of IP3R or SERCA. We demonstrate that GDC-0449 alters the intracellular Ca2+-homeostasis and inhibits cell growth in cisplatin-resistant lung cancer cells.

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 3360. doi:1538-7445.AM2012-3360
Abstract 3372: Mouse keratinocyte side-population plays an important role during malignant progression to skin squamous cell carcinomas
Authors: Kim Sun Hye , Lee Sung Hyun , Rodriguez-Puebla Marcelo
Published: August 2012

A subset of cells, termed side-population (SP), with characteristics of adult stem cells (SC) has been identified in several tissues, cell lines, as well as human and experimental tumors. The main feature of these putative stem cells is the high efflux capability for antimitotic drugs. The role of this SP in tumorigenesis is controversial; though, a role as cancer stem cells has been reported. Here, we have investigated whether a functionally equivalent SP exists in cell lines derived from mouse epidermis and skin tumors in order to define the extent of which the presence of SP is associated with tumor progression. We observed increased percentage of the SP in cell lines derived from skin squamous cell carcinomas (SCCs; cell lines CH72 and JWF2) compared with those arose from skin papillomas (308 and MT1/2) and mouse epidermis (C50). Side populations were isolated by the high capability to efflux Hoechst upon FACS analysis. Interestingly, qRT-PCR analysis of SP and non-SP shows elevated expression of the ABCG2/BCRP1 transporter -which participates in the dye efflux- in SP; while the expression of the hair follicle stem cell markers keratin 15 (K15), CD34 and Lgr6 were similar between SP and non-SP. These results suggest that the SP is not related to the well characterized stem cells from the bulge region of the hair follicle (BuSC). Importantly, the relevant correlation among the SP size and tumor progression suggests that these cells are positively selected during tumor progression. In order to localize the SP in mouse epidermis and tumors, we performed immunofluorescence analysis of skin papillomas and SCCs generated through the two-stage carcinogenesis protocol. We identified the ABCG2 transporter in a region near and above the BuSC area. Notably, this region was also positive for the thymic epithelial progenitor marker MTS24 which defines a keratinocyte population with characteristic of stem cells. Importantly, the ABCG2 transporter and MTS24 were localized in patches of cells on the proliferative basal cell layer of skin papillomas. Furthermore, we observed an elevated number of putative stem cells expressing ABCG2 and MTS24 in tumors from our previously published K5CDK4 mouse which showed increased malignant progression to SCC. Collectivelly, our results suggest that a putative stem cell population –different from the BuSCs–, play an important role during the malignant progression SCC. Supported by NIH grant CA116328.

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 3372. doi:1538-7445.AM2012-3372
Abstract 3840: Evaluation of the synergetic effect of a combination of dehydroxymethylepoxyquinomicin and gemcitabine on liver metastasis of pancreatic cancer
Authors: Suzuki Keiichi , Takeuchi Osamu , Takizawa Asako , Umezawa Kazuo , Kitagawa Yuko
Published: August 2012

Activation of the nuclear transcription factor-kappaB (NF-κB) has been implicated in the progression and metastasis of pancreatic cancer. This study was designed to evaluate the effects of a novel NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ) in inhibition of liver metastasis of pancreatic cancer in a clinical liver metastasis-mimicking mouse model in which cancer cells were intra-portal injected under small laparotomy. Moreover, the synergistic effect of combination therapy with DHMEQ and gemcitabine (GEM) was investigated. Cytotoxicity of DHMEQ and GEM was evaluated by cell growth inhibition assay. Both DHMEQ and GEM monotherapies inhibited cell growth of the human pancreas cell line AsPC-1. However, there was no synergistic effect in the combination therapy. For the in vivo study, male BALB/c nude mice were xenografted with intra-portal vein injection of AsPC-1. Mice were divided into four groups: 1) control (without any treatment), 2) GEM-treated group, 3) DHMEQ-treated group, and 4) combined treatment group (GEM+DHMEQ). Mice were fed for four weeks, and the number of liver metastases, induction of apoptosis in metastasis focuses and angiogenesis were investigated after sacrifice. The number of liver metastasis was decreased significantly in GEM group, DHMEQ group and GEM+DHMEQ group compared with control group. Significant inductions of apoptosis were revealed in GEM group and DHMEQ group compared with control group, in which apoptosis bodies in metastasis sections were counted by using the TUNEL method. Moreover, combination therapy of DHMEQ+GEM resulted in the strongest inductions of apoptosis. Tumor vessels were identified by immunohistochemical staining of tumor metastasis sections with an antibody against CD31. There was a large reduction in the number of CD31-positive vessels in the tumor of DHMEQ or/and GEM-treated mice as compared with control group. However, there was an inconsistency in the results of cell growth inhibition assay (in vitro) and mice metastasis model (in vivo). Thus we evaluated effect of combination therapy in the invasive potential of tumor cells by using chemoinvasion assay. The invasion ability was significantly inhibited in the GEM group, DHMEQ group and GEM+DHMEQ group. Furthermore, real-time PCR was performed to evaluate expression of mRNA of MMP-9. The expression levels of MMP-9 were inhibited in respective groups in the same order. In conclusion, the anti-tumor effects of combination therapy were significant, as evidenced by angiogenesis inhibition, apoptosis induction and invasiveness inhibition rather than cell growth inhibition.

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 3840. doi:1538-7445.AM2012-3840
Abstract 3844: A novel sorafenib-derivative SC-1 induces apoptosis in breast cancer cells through STAT3 inhibition
Authors: Liu Chun-Yu , Tseng Ling-Ming , Chang Kung-Chi , Shiau Chung-Wai , Su Jung-Chen , Chen Kuen-Feng
Published: August 2012

Background: STAT3 has emerged as a novel potential anti-cancer target and its signaling is constitutively activated in various cancers including breast cancer. Our previous study has shown that STAT3 is a major kinase-independent target of sorafenib in HCC. (J Hepatol. 2011). We have designed and synthesized a series of sorafenib analogues devoid of sorafenib's kinase inhibition activity, some of which showed stronger p-STAT3 inhibition and apoptosis-inducing effects than sorafenib in HCC cells (Eur J Med Chem. 2011). Here, we tested the efficacy of our previously published sorafenib derivative, SC-1, in breast cancer cells and examined the drug mechanism. Methods: breast cancer cell lines were used for in vitro studies. Apoptosis was examined by both flow cytometry and Western blot. Signal transduction pathways in cells were assessed by Western Blot. Tyrosine Phosphatase Assay Kit was used for SHP-1 activity assay. Gene silencing was done by small interference RNA (siRNA). In vivo efficacy of Sorafenib, and SC-1 were tested in xenografted nude mice. Results: Sorafenib, and SC-1 induced apoptosis in association with down-regulation of P-STAT3 and its downstream proteins Cyclin D1 and survivin in a dose-dependent manner in breast cancer cell lines (HCC-1937, MDA MB-468, MDA MB-231, MDA MB-453, SKBR-3, MCF-7) and the apoptotic effects induced by SC-1 were more potent than Sorafenib. Over-expression of STAT3 in MDA MB-468 cells protected cells from apoptosis induced by sorafenib and SC-1. Moreover, SC-1 up-regulated higher SHP-1 activity than sorafenib by in vitro phosphatase assays. Knockdown of SHP-1, but not SHP-2 or PTP-1B, by siRNA reduced apoptosis induced by SC-1. Importantly, SC-1 showed in vivo efficacy in MDA-468 xenografted tumor. These data indicated that inhibiton of P-STAT3 by up-regulating SHP-1 activity mediated apoptotic effects of sorafenib and SC-1 in breast cancer cells. Conclusions: novel sorafenib-derivative SC-1 induces apoptosis in breast cancer cells through SHP-1 dependent p-STAT3 inhibition. (Supported by NSC100-2325-B-002-036, NSC98-2320-B-010-005-My3 and NSC-100-2325-B-010-007, VGHTPE V100D-005-4, 101DHA0100318, and 101DHA0100230.) Keyword: Sorafenib, breast cancer, STAT3, SHP-1, apoptosis

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 3844. doi:1538-7445.AM2012-3844
Abstract 385: Potentiating MUC1 expression in human bronchial epithelial cells by cigarette smoke carcinogens through induction of TNF-α secretion from macrophages
Authors: Xu Xiuling , Chen Wenshu , Padilla Mabel T. , He Weiyang , Wang Qiong , Kim Kwang Chul , Lin Yong
Published: August 2012

Although an important role of inflammation in the development of lung cancer has been recognized, how inflammation promotes lung epithelial cell transformation and lung cancer development has not been well elucidated. Cigarette smoke (CS), the major cause of lung cancers, potently elicits chronic pulmonary inflammation. Our recent studies have found that CS significantly induces Muc1 (MUC1 for human and Muc1 for nonhuman species) expression in mouse bronchial epithelial cells and macrophages, and MUC1 facilitates Benzo(a)pyrene diolepoxide (BPDE)-induced human lung epithelial cell transformation. In this study, we investigated the role of inflammatory cells in regulating CS carcinogen-induced MUC1 expression in bronchial epithelial cells. BPDE and N-Nitroso-N-methylurea (MNU), an active CS carcinogen and a mimic, strongly induced tumor necrosis factor-alpha (TNF-α) secretion from human macrophages. The TNF-α induction was effectively blocked when ERK, JNK, and NF-κB were blocked, suggesting these pathways are involved in the induction of TNF-α from macrophages by BPDE and MNU. Interestingly, knockdown of MUC1 in macrophages suppressed BPDE- or MNU-induced TNF-α secretion, suggesting MUC1 plays a role in modulating carcinogen-induced and macrophage-mediated inflammatory responses. Conditioned media from BPDE- or MNU-treated macrophages potently induced MUC1 expression in human bronchial epithelial cells (HBECs), which was inhibited by a TNF-α neutralizing antibody, suggesting that TNF-α derived from macrophages contributes to CS carcinogen-induced MUC1 expression in HBECs. Thus, our results establish a dual role of MUC1 in CS-induced and inflammation-associated lung cancer development: to facilitate TNF-α secretion from macrophages and to potentiate transformation of HBECs. Note: This work is supported by NIH/NIEHS grant 1R01ES017328.

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 385. doi:1538-7445.AM2012-385
Abstract 3871: Insulin-like growth factor 1 receptor (IGF1R) inhibitor BMS754807 is active against FLT3-ITD mutated acute myelogenous leukemia and activity is p53 dependent
Authors: Borthakur Gautam , Duvvuri Seshagiri , Tsao Twee , Zhang Weiguo , Ruvolo Vivian , Lu Hongbo , Kojima Kensuke , Konopleva Marina , Andreeff Michael
Published: August 2012

The Internal tandem mutation (ITD) in the FLT3 gene is associated with shorter remission duration, overall survival and relapse free survival in patients with normal karyotype acute myelogenous leukemia (AML). FLT3-ITD inhibitors are in clinical development but single agent clinical activity is of limited duration with activation of parallel signaling pathways potentially contributing to most relapses thus highlighting the need for new agents. Because common signaling pathways are activated downstream of FLT3 and IGF1R, we investigated the preclinical activity of IGF1R antagonist BMS754807 against AML cells with FLT3-ITD mutations. Results: BMS 754807 induced apoptosis (Annexin V binding by flow cytometry) in MOLM13 cells (AML cell line with FLT3-ITD mutation and wild type p53) at 48 hrs at submicromolar concentrations, while OCI AML3 cells (p53 and FLT3 wild type) were resistant. Similarly, murine BAF3 cells expressing human FLT3-ITD underwent prompt apoptosis with BMS 754807 while the same cells with human wt-FLT3 were resistant to BMS 754807(IC50s 2.5 μmol vs >10 μmol). Western blot analysis confirmed reduction in FLT3, Akt, ERK, S6 ribosomal protein and GSK3 beta phosphorylation and increase in p53 levels in MOLM13 cells. Interestingly, apoptosis induction was not associated with caspase activation. Moreover, apoptosis induction by BMS 754807 appeared to be p53 dependent as MOLM13 cells with stable expression of short hairpin RNA (sh-RNA) targeting p53 (p53-shRNA) were resistant, while MOLM13 cells expressing scramble sh-RNA underwent apoptosis comparable to parental MOLM13 cells. Surface expression of IGF1R was comparable among parental and p53-shRNA MOLM13 cells. Apoptosis induction by BMS 754807 in p53-WT and FLT3-ITD cells was associated with phosphorylation of p53 at serine 15. Conclusion: BMS 754807 has selective activity against AML cells with FLT3-ITD mutation and this activity is p53 dependent and associated with phosphorylation of p53 at serine 15. Results suggest that IGF1R inhibition has therapeutic potential as novel targeted therapy for AML with FLT3-ITD mutation.

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 3871. doi:1538-7445.AM2012-3871
Abstract 3884: A novel, in vitro tankyrase 1 trans-ribosylation assay
Authors: George Jay , Benton Gabriel Jon , Woodgate Sandra , Xu Hai
Published: August 2012

The poly (ADP-ribose) polymerase, tankyrase 1, is an encouraging pharmacological target for cancer therapy. First discovered by its association with the TRF1, tankyrase 1 plays an important role in the maintenance of telomere length, sister telomere association, and mitotic spindle organization. More recently, interactions between tankyrase 1 and axin were shown to stabilize β-catenin and modulate Wnt signaling, enabling selective targeting of the Wnt pathway with tankyrase inhibitors. In addition, tankyrase 1 has also demonstrated potential as a target for synthetic lethality for BRCA-deficient cancers. Given the effect on these cancer-associated pathways, there is a growing interest for identifying tankyrase-specific inhibitors. Historical methods to evaluate tankyrase activity are not amenable for high throughput screening. Limited availability of the full length enzyme required radioactivity to attain the needed sensitivity. Truncation of tankyrase 1 improved solubility and increased availability, but the physiological response may not be equivalent to the full length enzyme. Many of these assays have also used modified substrates where molecules such as fluorescein or biotin are linked to NAD without characterizing the effects on enzyme activity. Most historical assays have also relied on measuring autoribosylation of tankyrase 1; whereas, transribosylation may be more relevant for assessing the activity of tankyrase 1 on other molecules. To address these issues, we have developed a novel, in vitro, high throughput assay for evaluating the transribosylation activity of tankyrase 1. This is accomplished using an ELISA format which semi-quantitatively detects poly (ADP-ribose) (PAR) deposited onto immobilized histone proteins by tankyrase 1. An anti-PAR monoclonal antibody, goat anti-mouse IgG-HRP conjugate, and HRP substrate generate a colorimetric or chemiluminescent signal, and the conversion of substrate correlates with tankyrase 1 activity. This assay ensures physiological significance by utilizing the full length enzyme and unmodified substrate in a transribosylation format, providing sensitivity down to pmols of enzyme. This assay is utilized to demonstrate the specificity of the tankyrase 1 inhibitor, XAV939, for tankyrase 1 compared to PARP1 and to reveal differential effects of activated DNA for full-length tankyrase 1 compared to the truncated enzyme.

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 3884. doi:1538-7445.AM2012-3884
Abstract 3886: Development of a new DNA aptamer against primary cultured tumor endothelial cells by a cell-based SELEX method to discover a new drug delivery system
Authors: Ara Mst. Naznin , Hyodo Mamoru , Ohga Noritaka , Hida Kyoko , Harashima Hideyoshi
Published: August 2012

The purpose of the present study was to develop DNA aptamers through a spontaneous cell-based SELEX method (systemic evolution of ligands by exponential enrichment) that specifically binding to cell surface proteins or biomarkers produced by primary cultured tumor endothelial cells (TECs). In solid tumors, new blood vessels are formed through an angiogenesis process, and this plays a critical role in cancer development as well as the development of metastasis. To combat angiogenesis, an appropriate diagnosis and understanding at the molecular level of different cancer types is now a high priority. Our initial study explored the use of the cell-based SELEX method, which has been applied in TECs to generate high affinity DNA aptamers. Our selected DNA aptamer AraHH001 bound specifically and with a high affinity to TECs in the nanomolar range but did not bind to normal skin endothelial cells (skin-ECs) and tumor parenchymal OSRC-II cells. The selected DNA aptamers also bounded to primary cultured human tumor endothelial cells (hTECs) isolated from a clinical patient with a renal carcinoma. Therefore, the development of specific DNA aptamers that bind to TECs is reported here for the first time. We conclude that such new DNA aptamers promise to hold great promise as targeted molecular probes that appear to play a major role in angiogenesis, drug delivery, identification of biomarker as well as in cancer therapy.

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 3886. doi:1538-7445.AM2012-3886
Abstract 3893: Inhalational temozolomide–a new mode of treating malignant gliomas
Authors: Chen Thomas C. , Cho Heeyon , Wang Weijun , Hofman Florence M.
Published: August 2012

Temozolomide (TMZ) is the standard of care chemotherapy for treatment of malignant gliomas; it is currently delivered orally or intravenously. Perillyl alcohol is a monoterpene which has been used to treat patients with malignant gliomas via an intranasal delivery system. Recently, we have constructed a new chemical entity (NCE) by conjugating temozolomide to perillyl alcohol via a carbamate bond. This new compound has been named TMZ-POH (NEO212). This new compound has been tested in-vitro in a number of assays. Its mechanism of action does not appear to be MGMT mediated, as addition of O6-benzylguanine has no effect on its cytotoxicity in glioma cells regardless of their MGMT status. On the other hand, TMZ-POH appears to induce endoplasmic reticulum stress (ERS) in malignant glioma cells, as demonstrated by an increase in glucose-regulated protein 78 (GRP78) and the apoptotic protein CHOP expression. MTT assays demonstrate that TMZ-POH is effective in both temozolomide sensitive and resistant U251, U87, LN229 malignant glioma cell lines. IC50 for colony formation assays (CFA) was determined for U251 temozolomide sensitive and resistant cells to be 18 uM and not achieved (0-60 uM). TMZ-POH, on the other hand, had IC50 of 10 uM and 30 uM respectively for TMZ sensitive and resistant U251 glioma cells. MTT assays using glioblastoma cancer stem cells (CSC) demonstrated that TMZ-POH induced IC50 cytotoxicity at 200 uM, compared to no cytotoxicity in the TMZ treated CSC. Moreover, TMZ-POH demonstrated no toxicity on normal astrocytes. Treatment of glioma cells with TMZ alone, POH alone, TMZ dissolved in POH, and TMZ-POH demonstrated that TMZ-POH was two orders of magnitude more cytotoxic than TMZ dissolved in POH. These data lead us to conclude that TMZ-POH is a NCE which may be evaluated for potential intranasal drug delivery to treat patients with malignant gliomas.

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 3893. doi:1538-7445.AM2012-3893
Abstract 3907: Discovery and characterization of AZ285 as a potent and selective inhibitor of CK2 kinase
Authors: Dowling James E. , Alimzhanov Marat , Bao Larry , Brassil Patrick , Cooke Emma L. , Denz Christopher R. , Liu Zhong-Ying , Ye Qing , Lyne Paul D.
Published: August 2012

Casein Kinase 2 (CK2) is a highly conserved and ubiquitously expressed serine/threonine kinase that regulates several key oncogenic signaling pathways, including PI3K/AKT, and NFkB and Wnt, and whose targeted overexpression in transgenic animal models results in neoplastic growth. Herein we describe the identification of AZ285, a potent pyrazolo[1,5-a]pyrimidine-derived inhibitor of CK2 with a high degree of kinase selectivity. AZ285 depletes levels of the CK2 substrates pAKTS129 and PTENS370 and induces apoptosis in cells in a concentration-dependent manner. Optimization of early leads was aided in part by cell wash-out experiments and X-ray cocrystallography with huCK2a and resulted in an agent with physical properties and DMPK characteristics suitable for evaluation in disease model studies.

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 3907. doi:1538-7445.AM2012-3907
Abstract 3927: Loss of bHLH transcription factor Id4 modulates androgen receptor activity in prostate cancer progression
Authors: Carey Jason P. , Chaudhary Jaideep
Published: August 2012

Inhibitor of differentiation 4 (Id4), a crucial developmental gene also expressed in the normal prostate, has been shown to act as a tumor suppressor in prostate cancer. Promoter hypermethylation of Id4 is observed in several advanced stage cancers including prostate cancer. The loss of Id4 expression correlates with androgen independent prostate cancer progression. Our studies suggest that Id4 plays a crucial role in mediating the transition from androgen dependent to androgen independent prostate cancer by mediating the AR axis potential and reprogramming several cellular mechanisms including migration, senescence and proliferation. Stable transfection of a full length Id4 plasmid into the androgen-independent prostate cancer cell line DU145 resulted in re-expression of AR and downstream AR response gene PSA. Id4 transfected cells also observed an androgen regulated rate of proliferation in responsive to treatment with AR antagonist, Casodex. AR antagonism also significantly reduced the rate of migration as observed by a scratch wound assay. Under closer observation, AR antagonist treatment with Casodex also inhibited translocation of AR to the nucleus of DU145 cells as observed by immunofluorescence. Previous studies in our laboratory have demonstrated that DU145+Id4 transfected cells undergo a significant level of senescence (∼ 32%) compared to normal DU145 cells (∼ 4%). Treatment of DU145+Id4 cells with the AR antagonist Casodex demonstrate that the rate of senescence in DU145+Id4 transfected cells is closely related to inhibition of AR activity. Our results suggest that Id4 may play a crucial role in the loss of AR activity in advanced stage prostate cancer progression. These results also suggest that the antagonism of AR nuclear translocation post Id4 induction closely regulates the rate of proliferation and the induction of a senescent phenotype. These results provide a significant correlation between Id4 expression and AR activity during prostate cancer progression. Loss of AR activity through Id4 promoter hypermethylation may play a crucial role in understanding castration resistant prostate cancer. Therefore, induction of Id4 may provide a novel therapeutic target for advanced stage prostate cancer treatment.

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 3927. doi:1538-7445.AM2012-3927
Abstract 394: Close association between subsided inflammation and the development of histologically less malignant HCC in HCV-associated LC
Authors: Tarao Kazuo , Miyakawa Kaoru , Kobayashi Satoshi , Ueno Makoto , Ohkawa Shinichi , Morinaga Soichiro , Nakamura Yoshiyasu , Miyagi Yohei , Okudaira Masahiko
Published: August 2012

Aim: We recently demonstrated that severe inflammation in the background cirrhotic tissue correlate with the development of histologically more malignant hepatocellular carcinoma (Edmondson III HCC) in HCV-associated liver cirrhosis (LC), and that histology activity index (HAI) was the only one significant contributor to the development of Edmondson III (Ed III) HCC in small nodular HCC. There is a possibility, in the contrary of this phenomenon, that subsided inflammation correlates with the development of histologically less malignant HCC (Ed I type HCC) and that long-term subsided inflammation correlates with the development of large Ed I HCC. We examined the possibility. Methods: Curative hepatic resection for HCC with LC was performed in 264 patients during the past 10 years in Kanagawa Cancer Center hospital. Of 264 patients 197 patients were anti-HCV-positive or HCV-RNA positive. Out of the 197 patients, 32 patients whose HCC revealed only one small HCC nodule (≤ 3 cm) were selected for this study. Furthermore, the cases whose HCC nodules were large (> 3 cm), but consisted of predominantly Ed I component, were also examined. For the evaluation of inflammation in the background LC, modified Knodell's histology activity index (HAI) was used. (for the evaluation of pure inflammation, items of fibrosis was omitted); piece meal necrosis (1-4), intra lobular cellular degeneration and focal necrosis (1-4), portal cellular inflammation (1-4), were estimated by two well experienced pathologist. In each case, the HAI score was estimated in five field and average HAI score was calculated. All the sections of resected HCC tissue was examined pathologically in all patients for determining the grade of malignancy according to Edmondson Steiner's classification; Ed I (well differentiated), Ed II (moderately diff.), Ed III (poorly diff.). Results: The average HAI score in 7 Ed I HCC patients was as low as 3.61 ± 0.70 (mean ± SD), and was significantly lower than that in 17 Ed III HCC patients (5.21 ± 1.15, P <0.001). Furthermore, the average HAI in the 5 cases whose HCC nodules were more than 3 cm and whose major component of HCC nodules were Ed I, was also as low as 3.55 ± 0.74. Conclusions: It is suggested that subsiding inflammation in the background non-cancerous cirrhotic portion might correlate with the development of histologically less malignant HCC.

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 394. doi:1538-7445.AM2012-394
Abstract 3942: The role of vHL and REDD1 in predicting sensitivity to targeted therapies in renal cell carcinoma
Authors: Blick Christopher , Ramachandran Anassuya , McCormick Robert , Cranston David , Harris Adrian L.
Published: August 2012

There are currently 6 FDA approved therapies in metastatic renal cell carcinoma and their introduction has improved both time to progression and survival in these patients. Despite treatment with targeted therapies approximately 20% of patients do not respond and the remaining patients will most likely develop resistance during the first 18 months of treatment. The aim of this study was to identify a link between differences in sensitivity to targeted therapies, the vHL status and the expression of genes involved in the mTOR pathway in both historic and primary renal cancer cell lines. Drug sensitivity and gene expression data was analysed in 6 historic and 10 primary renal cancer cell lines obtained from nephrectomy specimens. Gene expression data was also available from an additional 68 renal tumours. We found that cell lines with mutated or absent vHL showed increased sensitivity to rapamycin (p<0.01) but not to other therapies. Gene expression data showed that the expression of REDD1 (regulated in development and DNA damage responses 1), a known HIF1 target gene which inhibits the mTORC1 pathway in response to hypoxic stress correlates with rapamycin sensitivity (R-squared = 0.64, p=0.05). REDD1 expression was also higher in renal tumours when compared with matched normal tissue (p<0.01) and was found to correlate with CAIX expression (R-squared = 0.47, p<0.01). CAIX expression is associated with reduced survival in renal cell carcinoma and so further analysis is being performed to establish a potential role of REDD1 as a prognostic marker. Our findings suggest that vHL status and the levels of REDD1 expression in renal cancer cell lines can predict sensitivity to rapamycin.

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 3942. doi:1538-7445.AM2012-3942
Abstract 3947: Hypoxic regulation of RIO kinase 3 promotes cell migration and invasion
Authors: Singleton Dean C. , Rouhi Pegah , Cao Yihai , Harris Adrian L.
Published: August 2012

RIO kinase 3 (RIOK3) is an atypical serine/threonine protein kinase that is located on a focal amplification at 18q11 observed in several cancer subtypes. Dysregulated expression of RIOK3 has been implicated in migration and invasion of pancreatic cancer cells (Kimmelman et al., 2008). We identified increased RIOK3 expression in microarray analysis of MCF7 cells exposed to severe hypoxia (<0.01% O2) for 24 h. Given the importance of intratumoural hypoxia in promoting cell invasion and metastasis we hypothesised that RIOK3 may contribute to the enhanced migratory phenotype observed in hypoxia. The expression of RIOK3 mRNA was increased 3-9 fold in a panel of cell lines (MCF7, MDA-MB-231, HCT 116 and U-87 MG) following exposure to 0.1% O2 for 48 h. Likewise, RIOK3 protein levels were also increased in each of the cell lines after 24-48 h at 0.1% O2. Knockdown of either HIF-1α or HIF-2α using siRNA reduced the hypoxic up-regulation of RIOK3, suggesting that RIOK3 transcription is mediated by both HIF-1 and HIF-2. To investigate RIOK3 expression in tissue, immunohistochemistry was carried out on tumour spheroids. A modest increase in RIOK3 expression was observed in the hypoxic, pimonidazole-binding area adjacent to the necrotic core. Noticeably, the RIOK3 stain in these hypoxic regions relocalised to the cell membrane, in contrast to the predominantly cytoplasmic localisation in cells located in the oxygenated rim of the spheroid suggesting a role in cytoskeletal organisation. Depletion of RIOK3 using siRNA (siRIOK3) caused MDA-MB-231 cells to become long and spindle-shaped with a reduction of the number of lamellipodia, confirming a role for RIOK3 in cytoskeletal organisation. In the scratch wound assay, siRIOK3 caused a modest reduction in MDA-MB-231 migration in normoxic conditions but strongly inhibited migration in hypoxia. Likewise, MDA-MB-231 invasion through Matrigel was increased approximately 7-fold by 1% O2 and this effect was completely abolished in siRIOK3 cells. To investigate the role of RIOK3 in invasion and metastasis in vivo we utilised a zebrafish tumour model (Rouhi et al., 2010). Following implantation into the perivitelline cavity of developing embryos, metastasis of siRIOK3 cells was significantly reduced compared with control siRNA-transfected MDA-MB-231 cells resulting in 49% less disseminated cells and foci (P < 0.01). In addition to genomic amplification, we have demonstrated that HIF-dependent increased expression of RIOK3 occurs and contributes to cell migration and invasion in hypoxia. References: Kimmelman et al., (2008) PNAS 105(49): 19372-7 Rouhi et al., (2010) Nat Protoc. 5(12): 1911-8

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 3947. doi:1538-7445.AM2012-3947
Abstract 3951: Expression of SIRT1 and p27 during progression of human cervical cancer
Authors: Singh Sapna , Kumar P. Uday , Thakur Suresh , AR Poongothai , Ramakrishna Gayatri
Published: August 2012

Recent studies point to a close connection between cancer and ageing. Cellular senescence when initiated early in cancerous cells results in growth suppression due to permanent growth arrest. Sirtuins, belonging to family of the NAD-dependent deacetylases, play a crucial role in cellular metabolism and organismal ageing/ longevity. However, the role of human Sirtuin isoforms in malignancies and cellular senescence is still not clearly discernible. The present study is therefore designed to evaluate the correlation of SIRT1 expression with proliferation marker Ki-67, and growth arrest/senescence marker p27, during cervical cancer progression. The expression was evaluated by immunohistochemistry in 70 formalin fixed archival human cervical samples: normal/ASCUS (N= 20), squamous intraepithelial lesions (SIL N=20) and invasive squamous cell carcinoma (SCC, N= 30 samples). All the intraepithelial lesions and SCC cases were positive for human papilloma virus as detected by in-situ hybridization. The SIRT1 expression was either absent or feeble in cytoplasm of normal/ASCUS cervical epithelium, while a progressive increase in its expression was noted in 65% of preneoplastic lesions (SIL). Intriguingly, the invasive carcinoma showed heterogeneous pattern for both expression and localization of SIRT1: ranging from negative to strong expression levels and mixed localization pattern in cytoplasm only or both in nucleus and cytoplasm. The growth arrest/senescence marker p27 showed elevated level of expression in SIL cases compared to SCC (75%). Interestingly, the increased nucleo-cytoplasmic expression pattern of SIRT1 correlated well with the increased expression of p27 in the intraepithelial preneoplastic lesion. In conclusion, our results suggest activation of growth suppressive pathways by SIRT1-p27 regulation, atleast in the in preneoplastic lesions of cancer cervix which may help retard its progression to invasive cancer.

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 3951. doi:1538-7445.AM2012-3951
Abstract 3957: Cell death and growth arrest pathways mediating the actions of stilbene 5C in HCT-116 colon cancer cells
Authors: Alotaibi Moureq R. , Beckman Matthew J. , Di Xu , Lee Ray , Gewirtz David A.
Published: August 2012

The stilbene derivative, cis-3, 4′, 5-trimethoxy-3′-aminostilbene (stilbene 5c), is a potentially potent antitumor agent that acts via binding to the colchicine-binding pocket in microtubules. Earlier studies have shown that stilbene 5c induces cell death in ovarian cancer cells and leukemic cells (Lee RM et al, 2008; Lee RM et al, 2008). The present study was designed to investigate the effectiveness of this microtubule poison against the HCT-116 human colon cancer cell line and its mechanisms of action. Time course studies demonstrated that stilbene 5c produces a biphasic decrease in cell viability. The capacity of the cells to proliferate was not restored upon removal of the drug after 6 days of exposure. Consistent with the results of the time course studies, β-galactosidase staining indicated that treatment with stilbene 5c also promotes senescence. In addition to senescence, stilbene 5c-treated HCT-116 cells displayed formation of autophagic vesicles by acridine orange staining, which was supported by fluorescence-activated cell sorting (FACS). Further evidence of autophagy was derived from treatment of HCT116 cells carrying an RFP-LC3 construct with stilbene 5c, in which LC3 puncta formation increased in a time-dependent manner. DAPI staining, TUNEL, and Annexin 5 staining indicated that apoptosis is also occurring in stilbene 5c-treated HCT-116 cells. Cell cycle analysis demonstrated growth arrest at both G1 and G2/M, and an increase in the subG1 population at days 3 and 5, which correspond to senescence and apoptosis respectively. Interestingly, DAPI and Hoechst staining revealed morphological changes in the cell nuclei (binucleated and micronucleated cells), which suggest that mitotic catastrophe may also serve as a mode of cell death after treatment with stilbene 5c. Consistent with previous studies in other experimental cancer models, this work indicates that stilbene 5c could potentially be effective against colon cancer through the promotion of multiple modes of 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 3957. doi:1538-7445.AM2012-3957