bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5622: Development of an experimental model to test cellular therapy in combination with cytokines as a novel treatment for ovarian cancer
Authors: Ingersoll Susan Blaydes , Ahmad Sarfraz , Patel Sheylan , Ahmed Ahad , Edwards John R. , Finkler Neil J. , Holloway Robert W.
Published: February 2011

Because current therapies for ovarian cancer have little impact on long-term survival, there is a compelling need to develop innovative treatment strategies. Our aim was to develop in vitro and in vivo models to test cellular therapy in combination with cytokines or chemotherapies to elicit a graft versus tumor response to treat refractory ovarian cancer patients. SKOV-3 ovarian cancer cells, which were transfected with Red Fluorescent Protein (SKOV3-RFP) were passaged through nude mice to create more tumorigenic sub-lines. Two sub-lines were established, SKOV3-AF1 and SKOV3-AF2, which showed increased tumorigenicity compared to parental SKOV3-RFP cells. Both lines resulted in 100% tumor incidence in 6-8 weeks at a dose of 1 × 106 cells compared to 67% tumor incidence at 14 weeks at a dose of 5 × 106 SKOV3-RFP cells. SKOV3-AF1 and -AF2 cells were assayed to determine if peripheral blood mononuclear cells (PBMC) in combination with the cytokines IL-2 and IFNα-2b elicited a cytotoxic effect against the ovarian cancer cells. SKOV3-AF1 and-AF2 sub-lines were highly sensitive to cytotoxicity (up to 70%) mediated by PBMC (20:1 PBMC: SKOV3) in combination with IL-2 (25 ng/ml) and IFNα-2b (500 U/ml). The SKOV3-AF1 and -AF2 cells showed an average of 25% increased cytoxicity compared to parental SKOV3-RFP cells (p<0.05, n=3). Interestingly, SKOV3-AF1 and -AF2 were more resistant to IFNα-2b compared to SKOV3-RFP when cultured in the presence of IFNα-2b alone. In addition, gene expression of E-cadherin and Cysteine-rich 61 (CCN1), which have been shown to play a role in the patho-biology of ovarian cancer, was assessed in SKOV3-RFP, -AF1, and -AF2 cells as well as solid tumors harvested from mice. All SKOV3-derived lines and solid tumor expressed E-cadherin by RT-PCR. None of the SKOV3-derived lines expressed CCN1; however, one of the two SKOV3-AF1 solid tumors tested expressed CCN1. Both SKOV3-AF2 solid tumors evaluated showed weak expression of CCN1. The SKOV3-derived sub-lines that we developed will be a better model to test novel ovarian cancer treatment regimens because these lines were found to be more susceptible to PBMC-mediated cytotoxicity, exhibit increased resistance to IFNα-2b, are more tumorigenic in a xenograph model, and tumors harvested from these lines express genes that make these tumors more aggressive. Collectively, these results suggest that cytokine enhanced cellular therapy may be a viable treatment option for ovarian cancer patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5622.
Abstract 5628: Synthetic peptide mimics of LPS: Potential role as novel adjuvants
Authors: Suriano Robert , Shanmugam Arulkumaran , Rajoria Shilpi , George Andrea , Mittelman Abraham , Tiwari Raj K.
Published: February 2011

Lipopolysaccharide (LPS), the principal structural component of gram negative bacterial cell walls, is a potent activator of the immune system responsible for induction of septic shock or systemic inflammation in patients. This systemic inflammation mainly occurs through the interaction between LPS and toll like receptors (TLR-4 and TLR-2) present on antigen presenting cells (APC) thus leading to inflammatory cytokine (TNFα, IL-12, and IL-1β) secretion. Apart from the negative side effects associated with LPS, it mimics an essential and desirable property sought after in developing an optimal adjuvant, namely inducing inflammation and it is this inflammatory property which enables an adjuvant to act as a catalyst in initiating an optimal immune response. Therefore, development and or identification of a compound(s) which can act as an adjuvant by mimicking LPS but lack its harmful systemic side effects is very intriguing. As an initial approach to develop LPS mimics, we used Peptide Phage Display Technology. The peptide library which we used was composed of random linear 7-mer peptides and we identified several peptides which displayed high reactivity with LPS specific antibodies thus suggesting their capability to function as LPS specific peptide mimics. Upon interaction of LPS with TLR-4 and TLR-2 receptors, the one essential event which is at the core of APC activation and initiation of nuclear translocation of nuclear factor kappa B (NFκB). Thus, in order to determine if our peptides functionally mimic LPS, we assessed if they are capable of inducing NFκB nuclear translocation in human embryonic kidney (HEK) cells which are stably transfected to express either TLR-4 or TLR-2. The LPS peptide mimics identified in our study were capable of activating both TLR-4 and TLR-2 thus not only validating the fact that they are LPS peptide mimics but that they are functional LPS mimics and are capable of inducing NFκB nuclear translocation just as efficient as LPS. Identification of LPS peptide mimics opens up a new area in the development of adjuvants which can not only induce localized inflammation but also abrogate the systemic effects of LPS.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5628.
Abstract 563: Novel role of VEGF and neuropilin-1 in breast cancer tumor-stromal interactions
Authors: Qu Zhican , Roy Anshu M. , Maxuitenko Yulia Y. , Li Rongbao , Huang Zhi Qiang , Johnson Martin R.
Published: February 2011

Human breast cancers contain high levels of fibroblastic stroma as a critical feature of desmoplasia. The complex interactions between tumor and stromal cells play important roles in tumor growth, metastasis and resistance to anticancer treatments. Our previous in vivo studies showed that increased levels of tumor-released VEGF were associated with increased desmoplastic responses and resulted in a hormonal resistance phenotype of ER+ breast tumor. Based on our findings, a clinical trial conducted at UAB with a new combinational treatment targeting both ER and VEGF signalings has achieved significant objective response in ER+ breast cancer patients. In our current studies, we further studied the role of VEGF in mediating tumor-stromal interactions and initiation of desmoplasia. Our results have shown that tumor released VEGF interacts with stromal fibroblasts which express VEGF receptors R1, R2 and Neuropilin-1 (NRP1), thereby stimulating their infiltration to promote desmoplastic response. Down regulation of NRP1 expression by siRNA significantly abolished the fibroblast chemo-attractive motility towards VEGF, while the VEGFR1 and VEGFR2 blocking antibodies had no effects on their migration mobility, suggesting that NRP1 expressed in fibroblast is involved in tumor-stroma cell interactions in breast cancer. Our studies using breast cancer xenograft mouse model with regulated tumor VEGF expression revealed that tumor VEGF expression was positively correlated with expression of NRP1 and alpha smooth muscle actin (α-SMA, a transformed/myo fibroblast marker) in the tumor stroma. In addition, levels of tumor VEGF, stromal NRP1 and α-SMA were all positively correlated with level of tumor stromal content and tumor growth. Blocking tumor VEGF with a neutralizing antibody (Avastin) as a treatment modality in xenograft mice reversed the VEGF increased desmoplasia. Our study results reveal a novel role of VEGF and NRP1 in tumor-stromal interactions and desmoplasia, indicating NRP1 can be a therapeutic target for breast cancer treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 563.
Abstract 5631: Nitric oxide-based immune response modifications: A novel paradigm in tumor vaccine development against melanoma
Authors: Olson Samuel Y. , Konishi Tamiko , Bruhn Kevin W. , Craft Noah A. , Garban Hermes J.
Published: February 2011

Although of cardinal importance, the specific role of nitric oxide (NO) in the immune response to cancer remains elusive. NO is generally considered to act as a terminal effector molecule that will promote direct cell death due to its cytotoxic and/or cytostatic properties. Conversely, NO has been also found to be associated with a cytoprotective effect due to its ability to interfere with the apoptotic machinery. We have previously shown that NO is capable to immuno-sensitized tumor cells by regulating the expression of apoptosis-related genes and modifying the structure of many protein targets. Thus, we hypothesize that NO-based modification of an autologous tumor vaccine preparation may improve the immunological priming against tumor cells and potentiate the specific anti-tumor immune response. In order to test this hypothesis we used the well-characterized B16-C57BL/6 syngeneic mouse model of melanoma. B16-F0 melanoma cells were cultured in the presence or absence of a non-cytotoxic concentration of a slow rate release NO donor for 18 hours, and later homogenized into a crude lysate. These preparations were used to vaccinate mice previously challenged with B16-F0 melanoma cells on the contralateral dorsal flank one week before, in order to frame a therapeutic paradigm of treatment in cancer. Additional doses of vaccine were applied every 7 days for a period of 3 weeks and tumor volume was determined every 3 days. Our results demonstrate that the NO-modified autologous cancer vaccine decreases the rate of tumor growth by approximately 85% (p <0.001) by day 25 when compared with the control groups. In addition, this vaccination scheme increases the survival rate by approximately 60% (p <0.001) of the experimental group when compared with controls. NO can exert a myriad of modifications at the genetic, epigenetic and post-translational level in the tumor cells promoting a robust and effective therapeutic immune response against cancer cells. Currently, we are defining the molecular and immunological mechanisms responsible for the significant increase in survival and anti-tumor immune response triggered by the NO-mediated modifications of the melanoma tumor cells. Our results suggest a new role of NO as an immune response modifier that can be exploited in cancer immunotherapy and serves as a model for vaccine development.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5631.
Abstract 5632: Mechanism of anemia response by lenalidomide in treating patients with primary myelofibrosis (PMF) and ET-MF is related to suppresion of T regulatory cells (Treg)
Authors: Kafeel Muhammad I. , Sun Yiwu , Chen Chi , Hakimi Neal , Rathnasabapathy Chentyl , Singh Amrit , Lichter Stephen , Wang Jen Chin
Published: February 2011

Except allogenic bone marrow transplantation with either myeloablative or reduced intensity conditioning, there is no effective treatment for PMF. Age-related morbility and mortality factors limit this application. Anti-Jak2 treatment relieves splenomegaly but does not improve cytopenia. IMiDs on the other hand can improve anemia in up-to 20% of transfusion dependent anemic patients with PMF. In order to asses the underlying mechanism and to predict treatment responsiveness, in vitro suppression of Treg cells by lenalidomide correlated to clinical treatment response was performed. Seven patients with transfusion dependent and ESD (erythropoietin stimulating drugs) resistant PMF were studied. Mononuclear cells from blood in patients with PMF were cultured in the culture medium with FCS and Il-2 (100 IU/ml) in the presence of lenalidomide or DMSO for 6 days, the cells were then stained for Treg cells (CD4+, CD 25 +,and FoxP3+,) and analyzed by flow cytometry using Treg Detection Kit from Miltenyi Biotec Inc (Auburn, CA). Treg cells were enumerated as percentage of selected CD4 + cells. The results showed that in the 4 patients who responded to lenalidomide treatment, Treg cells were suppressed by the in vitro testing by lenalidomide, while in the three patients who were clinically refractory to lenalidomide treatment, their Treg cells were not suppressed by in vitro lenalidomide treatment. These results suggest that in transfusion dependent PMF, Treg cells may play a role in the pathogenesis of anemia and that effectiveness of lenalidomide treatment may be partly related to its suppression of Treg cells. Further studies to recruit more patients and to explore the role of Treg cells in modulating erythroipoiesis in PMF using the erythroid methylcellulose culture systems are currently in progress.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5632.
Abstract 5634: Chemical antibodies for cancer immunotherapy
Authors: Evbuomwan Moses O. , Maeda Yoshiko , Kumaresan Pappanaicken , Lam Kit S.
Published: February 2011

The absence of curative therapies for recurrent forms of metastatic cancer has prompted a vigorous search for novel treatment strategies. Cancer immunotherapy uses the host immune system, either directly or indirectly, to combat cancer. The more successful cancer immunotherapies are antibody-based. In this study we hypothesized that a chemical antibody (chembody) with an intact Fc region can be constructed by conjugating tumor cell specific peptidomimetic agents (ligands) to the Fab region of human IgG (hIgG). The ligand of interest, RGD, binds effectively to αVβ3 integrin expressed on tumor cells. The resultant chembody will have the ability to opsonize the tumor cells and elicit host immune response against cancer cells by recruiting the immune effector cells. In this study, we (1) conjugate naïve hIgG with the ligand, (2) verify ligand conjugation, and (3) test the efficacy of the chembody. The 2-iminothiolane conjugation method was employed to conjugate the ligand to naïve hIgG. The conjugation was verified by performing Western blot analysis, MALDI-MS assay, and cell binding assay. The Western blot and Coomassie blue staining showed that conjugation was successful while the MALDI-MS assay showed a 1:3 conjugation ratio. Colorimetric cytotoxicity assay will be used to test the efficacy of the chembody. We expect chembodies with intact Fc region to be tumor specific, and actively recruit immune cells to the tumor site and have low immunogenicity. This novel individualized medicine approach in cancer immunotherapy can be very effective in eliminating the remaining cells responsible for relapse after chemotherapy or radiotherapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5634.
Abstract 5643: Enhancement of tumor radiosensitivity by sorafenib
Authors: Kim Yong Bae , Jeung Hei Cheul , Rha Sun Young , Chung Hyun Cheol , Kim Gwi Eon , Cho Nam Hoon
Published: February 2011

Purpose: Sorafenib, an orally available multikinase inhibitor, is approved by the U.S. Food and Drug Administration for the treatment of patients with advanced renal cell carcinoma and those with unresectable hepatocellular carcinoma. However, there has been no data about synergistic interaction between sorafenib and radiation. In this study, we investigated the possible sorefenib-induced enhancement of radiosensitivity.

Experimental Design: The effects of sorafenib on the in vitro radiosensitivity of DLD-1 and HT-29 (colon cancer) cell lines were evaluated using clonogenic assay. The impact of sorafenib on radiation-induced cell cycle kinetics and on apoptosis was analyzed using flow cytometry evaluated via propidium iodide and annexin V. ERK signaling were examined by Western blot analysis. DNA damage and repair were evaluated using phosphorylated histone H2AX (γH2AX). Tumor growth delay was used to evaluate the effects of sorafenib on in vivo (DLD-1) tumor radiosensitivity.

Results: Exposure of each cell line to sorafenib combined with irradiation resulted in an increase in radiosensitivity with dose enhancement factors at a surviving fraction of 0.25 ranging from 1.21 to 1.61. Sorafenib and radiation induced accumulation of tumor cells in G2-M phase, but had no effect on radiation-induced apoptosis. As a measure of DNA double strand breaks, γH2AX foci were determined as a function of time after irradiation + sorafenib combination. Irradiated-alone cells showed more rapid reduction of γH2AX foci than irradiation + sorafenib combination cells. Tumor xenograft studies confirm that administration of sorafenib results in profound tumor growth inhibition when combined with radiation.

Conclusions: These results indicate that sorafenib can enhance tumor cell radiosensitivity in vitro and in vivo and suggest that this effect involves G2-M phase arrest and an inhibition of DNA repair.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5643.
Abstract 5645: Growth inhibitory activity of ethanol extracts of Chinese and Brazilian propolis in human colon carcinoma cell lines
Authors: Yoshida Ichiro , Nakashima Makoto , Ishihara Masashi , Morioka Takamitsu , Itoh Yoshinori , Yoshimi Naoki , Suzui Masumi
Published: February 2011

Propolis is a natural product derived from plant resins collected by honeybees, and has been used globally as a folk medicine for centuries. More than 300 bio-active compounds have been identified from bee propolis. In the current study, we examined whether the ethanol extracts of Chinese and Brazilian propolis exert anticancer activities in four human colon carcinoma cell lines, CaCo2, HCT116, HT29 and SW480. Propolis samples were extracted with ethanol, and the crude extracts were dissolved in dimethylsulfoxide and used for the following experiments. We also examined the effects of the ethanol extract of Chinese propolis on cell proliferation, cell cycle progression, apoptosis, and the levels of expression of cell cycle control molecules in the HCT116 and HT29 cell lines. In the HCT116, HT29 and SW480 cell lines, the extracts of both Chinese and Brazilian propolis caused a marked dose-dependent growth inhibition, with IC50 values in the range of 4-41 μg/ml. In the FHC normal human colonic epithelial cell line, the extract of Chinese propolis failed to cause a marked growth inhibition, the growth inhibition rate was about 20%, whereas it was about 90% in the HCT116 and HT29 cell lines. In the HCT116 cell line, at concentrations of 10 and 20 μg/ml the extract of Chinese propolis caused a marked increase in sub-G1 fraction of cells in a dose-dependent fashion. The propolis extract (20 μg/ml) caused a significant increase of cells in sub-G1 and this increase was associated with a concomitant relative decrease of cells in the G1, S and G2-M phases of the cell cycle, indicating that Chinese propolis extract induced apoptosis in the HCT116 cell line. In addition, Chinese propolis extract caused a dose-dependent increase in the cellular mRNA levels of p21CIP1 and p53 in the HCT116 cell line. These findings indicate that the ethanol extracts of propolis contain components that may have anticancer activity. Thus, propolis and related products may provide a novel approach to the chemoprevention and/or chemotherapy of human colon carcinoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5645.
Abstract 5646: Protein-bound polysaccharide from Phellinus linteus inhibits tumor growth, invasion and angiogenesis of SW480 human colon cancer cells by modulating Wnt/b-catenin signaling
Authors: Song Kyoung-Sub , Li Ge , Kim Tae-Dong , Kim Jong-Seok , Shin So-Yeon , Jing Kaipeng , Park Jong-Il , Kweon Gi-Ryang , Hwang Byung-Doo , Yoon Wan-Hee , Lim Kyu
Published: February 2011

It is known that polysaccharide extracted from Phellinus linteus (PL) mushroom possess antitumor activity. We previously have demonstrated that PL has direct antitumor effect through apoptosis and G2/M cell cycle blockade in SW480 human colon cancer cells. However, the molecular mechanisms responsible for antitumor and antiinvasive behavior of PL remain to be explored.

Employing SW480 colon cancer cells which are overexpressed B-catenin, we demonstratd that PL significantly inhibited cellular proliferation and remarkable decrease of B-catenin expression on Western blot and indirect immunofluorescence detection in PL treated cells. Cyclin D1, one of the B-catenin controlled downstream genes and TCF/LEF transcription activity were also significantly reduced when PL was treated. PL inhibited in vitro invasion and motility of SW480 cells and the activity of matrix metalloproteinase (MMP)-9 on zymography. In addition, PL inhibited human umbilical vein endothelial cell (HUVEC) proliferation and capillary tube formation. Tumor growth of SW480 cells implanted into nude mice were significantly inhibited with PL treatment in a dose-dependent manner. Immunohistochemical analysis of xenografted tumor tissue showed that apoptotic index was markedly increased and nuclear staining of b-catenin was decreased. However, the proliferation index and microvessel density were significantly decreased. These data demonstrate that PL downregulates Wnt/b-catenin signaling pathway and inhibits multiple steps in tumor invasion in certain colon cancer cells.

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

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5646.
Abstract 5655: 3,3′-Diindolylmethane selectively induces proteasomal degradation of the class I histone deacetylases
Authors: Li Yongming , Li Xia , Guo Bin
Published: February 2011

This study aims to identify the molecular target of 3,3′-Diindolylmethane (DIM), an anti-cancer agent that induces cell cycle arrest and apoptosis through unknown mechanisms. Previously, we have shown that DIM can enhance the efficacy of butyrate in colon cancer prevention in the APCmin/+ mouse model [Cancer Prevention Research, 2(6):581-9, 2009]. In our studies trying to identify the intracellular target of DIM, we found that DIM selectively induced proteasome-mediated degradation of the class I histone deacetylases (HDAC1, HDAC2, HDAC3, and HDAC8) in colon cancer cells, without affecting other HDAC proteins (class II or class III HDACs). DIM-induced down-regulation of the class I HDACs was also observed in vivo in tumor xenografts in nude mice. The depletion of the HDACs by DIM caused a reduction of the HDAC activity on the promoters of CDKN1A/WAF1/CIP1 and CDKN1B/KIP1 genes (encoding cyclin-dependent kinase inhibitors p21 and p27, respectively) and significantly increased the expression of p21 and p27, which arrested cells at the G2 phase of the cell cycle. The degradation of the HDACs also caused DNA damage and triggered apoptosis. Based on these data, we conclude that DIM acts by selectively targeting the class I HDACs to promote their degradation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5655.
Abstract 5656: Role for Sphingosine kinase 1 in head & neck cancer
Authors: Shirai Keisuke , Furuya Hideki , Wada Masayuki , Bielawski Jacek , Ogretmen Besim , Hannun Yusuf A. , Obeid Lina M. , Kawamori Toshihiko
Published: February 2011

Novel and effective targets for cancer therapy and prevention are increasingly important in cancer research, especially for head and neck squamous cell carcinoma (HNSCC), which is one of the most lethal cancers. A potential target for this type of cancer might be sphingosine kinase 1 (SphK1) which phosphorylates sphingosine to form sphingosine-1-phosphate (S1P) because it is a critical regulator of sphingolipid-mediated functions and the SphK1/S1P pathway has been implicated in several important biological functions including inflammation and carcinogenesis. To investigate the potential of SphK1 as a target in head and neck cancer development, we used a 4-nitroquinoline-1-oxide (4-NQO)-induced carcinogenesis tongue model in SphK1 knockout mice. All mice were treated with 4-NQO at 40 μg/ml in drinking water for 14 weeks (untreated water was available thereafter, until the end of the experiment). All animals were sacrificed at 20 weeks and animal tongues were examined. We found that SphK1 positively stained in tongue cancer induced by 4-NQO in wild type mice, and 72% SphK1 KO mice developed tongue cancer, whereas 96% of the wild type mice did (P<0.05). Furthermore, tongue cancer volume was significantly decreased in SphK1 KO mice (P<0.05). To understand how SphK1 is responsible for decreasing tongue cancer, we used a BrdU incorporation assay to evaluate cell proliferation and used a cleaved caspase-3 immunohistochemistry assay to indicate apoptosis in tongue cancer tissues. We found that tongue cancers in SphK1 KO mice had significantly less cell proliferation and increased apoptosis compared to in wild type mice (P<0.01 and P<0.001, respectively). Assaying for sphingolipid profiles in mouse blood, we found that S1P was significantly reduced in SphK1 KO mice (P<0.001), and that C16-ceramide was also significantly reduced in SphK1 KO mice compared to wild type mice (P<0.05). These data are consistent with our previous results (Cancer Lett., 256: 101-111, 2007). We also found that 4-NQO-activated phospho-Akt was reduced in tongue cancers in SphK1 KO mice, suggesting that the SphK1/S1P pathway may be involved in PI3K-Akt-mTOR pathway in HNSCC development. Our data suggest that the SphK1/S1P pathway may mediate HNSCC development and that inhibition of this pathway may be an effective and novel target for chemoprevention against HNSCC.

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

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5656.
Abstract 5666: Nrf2-mediated induction of phase 2 detoxifying enzymes by an active compound isolated from Chrysanthemum zawadskii
Authors: Seo Jiyeon , Lim Ji Sun , Park Jia , Nam Dae Hwan , Garcia Annalene , Kim Hyo Jung , Lim Soon Sung , Lee Choong Hwan , Park Jung Han Yoon , Kim Jong-Sang
Published: February 2011

Previous study demonstrated that methanolic extract of Chrysanthemum has the potential to induce detoxifying enzymes such as NAD(P)H:(quinone acceptor) oxidoreductase 1 (EC 1.6.99.2) (NQO1, QR). In this study we further fractionated methanolic extract of Chrysanthemum and investigated the detoxifying enzyme-inducing potential of each fraction. The fraction shown the highest NQO1-inducing activity was found to contain (+)-(3S,4S,5R,8S)-(E)-8-acetoxy-4-hydroxy-3-isovaleroyloxy-2-(hexa-2,4-diynyliden)-1,6-dioxaspiro[4,5]decane (CZ-5) which increased NQO1 enzyme activity in a dose-dependent manner. And the compound (CZ-5), like most phase 2 enzyme inducers, caused a increasing expression pattern of phase 2 detoxifying enzymes in a dose-dependent manner in mouse hepatoma Hepa1c1c7 and BPRc1 cells. Moreover, CZ-5 caused a dose-dependent enhancement of luciferase activity in HepG2-C8 cells generated by stably transfecting antioxidant response element-luciferase gene construct, suggesting that it induce antioxidant/detoxifying enzymes through antioxidant response element (ARE)-mediated transcriptional activation of the relevant genes. CZ-5 also stimulated nuclear accumulation of Nrf2 as evaluated by western blot analysis. In conclusion, our data showed that CZ-5 acted as a potent phase 2 detoxifying enzyme inducer by stimulating the nuclear accumulation of Nrf2 and had potential as chemopreventive agent

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5666.
Abstract 5676: Farnesoid X receptor-mediated carcinogenic effects of bile acid in esophageal cancer: A potential chemoprevention target
Authors: Guan Baoxiang , Xu Xiaochun
Published: February 2011

OBJECTIVES: The incidence of esophageal adenocarcinoma is increasing in the United States. Frequent gastroesophageal reflux or gastroesophageal reflux disease, resulting in Barrett esophagus, may be responsible for the increase. In the present study, we determined the carcinogenic effects of bile acid in esophageal cancer and then explored the use of the farnesoid X receptor (FXR) inhibitor guggulsterone to control tumor cell viability and gene expression. METHODS: Cell culture, Western blot, RT-PCR, gene transfection, and immunohistochemistry assays were used. RESULTS: We found that bile acid inhibited RAR-β2 and RRIG1 but induced COX-2 expression in a dose- and time-dependent manner and that FXR, the bile acid receptor, was responsible. Furthermore, bile acid also induced FXR expression in esophageal cancer cell lines. Knockdown of FXR expression using FXR shRNA antagonized the effects of bile acid in gene expression. We then demonstrated that guggulsterone treatment was able to reduce the viability of esophageal cancer cells and induce RAR-β2 and RRIG1 expression but suppress COX-2 and MMP-9 expression. In addition, ex vivo data demonstrated that FXR was highly expressed in both esophageal squamous cell carcinoma (71%) and adenocarcinoma (81%) tissues and was associated with reduced RAR-β2 and RRIG1 expression. CONCLUSIONS: Suppression of FXR activity using FXR shRNA or its inhibitor guggulsterone was able to antagonize bile acid in regulating gene expression and cancer viability.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5676.
Abstract 5678: Kavalactone yangonin induces autophagy, inhibits TSC-mediated translation initiation and acts synergistically with a kava chalcone flavokawain A on growth inhibition in bladder cancer UMUC-3 cells
Authors: Liu Zhongbo , Li Xuesen , Simoneau Anna , Zi Xiaolin
Published: February 2011

Autophagy is a tightly regulated lysosomal self-digestion process that has been shown to suppress primary tumor formation. However, the mechanisms and potential usefulness of autophagy induction in cancer prevention remain controversial and largely unknown. To facilitate the study of the potential of autophagy induction as a mechanism for bladder cancer prevention, we have established a bladder cancer cell line with a stably over-expressed EGFP-LC3 gene (a hallmark gene for autophagy). Using this cell line, we screened out kavalactones yangonin and dehydrokawain as strong autophagy inducers in bladder cancer cells, but not the previously defined apoptosis inducers flavokawains also found in kava root extracts. Yangonin treatment at concentrations of 1.25 to 50 μg/ml for eight hours significantly increases the percentage of EGFP-LC3 cells with punctuate EGFP-LC3 fluorescence up to 80%. The induction of autophagy by yangonin treatment was further confirmed by electron microscopy observation of increased autolysosome formation and by western blotting analysis of LC3-II cleavage. The effect of yangonin on autophagy induction corresponds to its anchorage-dependent and independent growth inhibitory effect in a dose and time dependent manner in UM-UC-3 cells. Similarly, yangonin also induces autophagy and inhibits cell growth in another bladder cancer cell line T24. Further study demonstrated that yangonin is less effective in reducing the cell viability of the primary mouse embryo fibroblasts tuberous sclerosis-1 knockout (MEF TSC1−/−) than that of wild-type cells (MEF TSC1+/+) cells. This result suggested that TSC1 may be, at least in part, required for the growth inhibitory effect of yangonin. Immunoprecipitation experiments showed an increased formation of the TSC1/TSC2 immunocomplex after yangonin treatment in UMUC-3 cells. In addition, yangonin treatment of UMUC-3 cells resulted in a decrease in phosphorylation of mTOR and 4E-BP1 with subsequent increased binding of 4E-BP1 to m7GTP, which is responsible for stoppage of translational initiation. Interestingly, yangonin in combination with flavokawain A, an apoptosis inducer, synergistically inhibits the growth of UMUC-3 cells. Taken together, our results may suggest a novel strategy for bladder cancer chemoprevention through combination of autophagy and apoptosis inducers, yangonin and flavokawain A.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5678.
Abstract 5682: Tanshinones in Salvia miltiorrhiza as potential chemopreventive agents against lung cancer
Authors: Li Yanli , Gong Yi , Li Linglin , Zhou Jin-Rong
Published: February 2011

The search for effective regimens with minimal adverse effects for the prevention and treatment of lung cancer remains the top priority research to eradicate this devastating disease. Several essential components determine the opportunity of success in identifying the candidate compounds, which include enhanced tissue levels, preferably in lungs after administration, safety use profiles, and more importantly preclinical evidence that is derived from clinically relevant in vivo systems. A Chinese herb medicine Salvia miltiorrhiza (Danshen) has been widely used for centuries for treatment of cardiovascular diseases without reported side effects to healthy humans. After oral administration, tanshinones are preferably accumulated at the highest levels in lungs. Several Danshen compounds, such as tanshinone IIA (T2A), tanshinone I (T1) and cryptotanshinone (CT), have also been reported to have potent activities in vitro against several cancer types including lung cancer. These promising findings strongly support that tanshinones may have potent anti-cancer, especially anti-lung cancer activities. The long-term goal of this research is to develop tanshinones as effective and safe agents for the prevention and treatment of lung cancer. We first evaluated the effects of tanshinones on the growth inhibition of lung cancer cell lines in vitro. All three tanshinones showed dose-dependent inhibition to the growth of human (H1299, H23, and A549) and murine (LLC) lung cancer cell lines at low μM ranges with T1 the most potent. Interestingly, LLC, which is usually resistant to drug treatment, was the most sensitive cell line to T1 treatment (IC50 at 3μM), but it was insensitive to T2A treatment. Cell cycle analysis showed that CT and T1 arrested cells (H1299) at S phase, whereas T2A arrested cells at G2/M phase. The growth inhibition and cell cycle arrest activities of tanshinones were associated with downregulation of cdc2 and Aurora A expression. Because T1 showed the most potent activity, we are evaluating its effect on the growth inhibition of lung tumors in mice and on the modulation of cellular and molecular markers. It is expected that the studies will provide experimental evidence to support the chemopreventive and/or therapeutic activities of tanshinones against lung cancer.

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

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5682.
Abstract 5683: The dietary anti-estrogenic agent 3,3′-diindolylmethane inhibits metastatic propensity in thyroid cancer cells
Authors: Rajoria Shilpi , George Andrea , Shanmugam Arulkumaran , Megwalu Uchechukwu , Schantz Stimson P. , Geliebter Jan , Tiwari Raj K. , Suriano Robert
Published: February 2011

The incidences of thyroid proliferative diseases (TPD) including thyroid cancer and goiter are ever increasing with thyroid cancer being the most common among endocrine cancers. Recent statistics reveal 37,000 new cases diagnosed in US alone in 2008 and worldwide almost 27 million patients are affected. Diet has always been of prime importance in its association with cancer development and prevention. Several studies have found inverse association of cancer risk with consumption of dietary products, such as tomatoes, soy and cruciferous vegetables. We have been studying the effect of DIM (3,3′-diindolylmethane), a chemopreventive agent against hormone responsive cancers. In this study we show that thyroid cells express functional estrogen receptor (ER) -α and ER-β and DIM has anti-cancer effects on estrogen responsive thyroid cancer cells. Interestingly, we found that DIM does not affect the levels of ER but it does target metastatic phenotype of thyroid cells as evidenced by decreased adhesion, invasion and migration in vitro. In an attempt to define the cellular target of this inhibition, we observed that DIM mediates down-regulation of matrix metalloproteinases (MMPs) and cell adhesion proteins, integrins. This correlates with decreased thyroid cell proliferation and inhibition of metastatic propensity by DIM in thyroid cancer cells. These preclinical studies are being extended to the clinic where the anti-estrogenic property of DIM is being examined in goiter patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5683.
Abstract 5684: B-catenin-dependent and independent changes in gene expression induced by sphingolipids
Authors: Zhou Hui , Schmelz Eva M.
Published: February 2011

Dietary supplementation with sphingolipids inhibits colon tumorigenesis in carcinogen-treated CF1 mice and in multiple intestinal neoplasia (Min) mice that produce intestinal tumors spontaneously. In both cancer models the regulation of β-catenin by sphingolipid metabolites is an important early event. Stabilization and nuclear translocation of β-catenin and its interaction with T-cell factor (TCF)/lymphoid enhancer factor (LEF) play important roles to activate the transcription of genes associated with cancer development and progression. Sphingosine and ceramides, major digestion products of complex sphingolipids in the diet, down-regulate β-catenin transcriptional activity in a dose- and time-dependent manner. Our data indicate that sphingosine and ceramides suppress SW480 human colon cancer cell growth in a concentration-dependent manner. In the present study, we investigated the dependency of sphingosine- and ceramide-induced changes in gene expression on β-catenin transcriptional activity by comparing control and β-catenin siRNA treated cells. We observed changes in the expression of genes involved in signal transduction, transcription factors, cell cycle control and DNA damage repair, cell adhesion, cell invasion and metastasis, angiogenesis, and apoptosis and cell senescence. Most genes were regulated by all metabolites; however, some genes were only targeted by specific metabolites. Furthermore, only a small number of genes regulated by the sphingolipid metabolites relied completely on the activation of the β-catenin transcriptional activity. Further experiments are currently being performed to confirm the function of β-catenin on the regulation of these genes.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5684.
Abstract 5685: The effects of spinach and two of its components, spinacetin and patuletin, on the treatment of prostate cancer
Authors: Jackson Glenn A. , Slusarz Anna , Drenkhahn Sara K. , Starkey Nicholas J. , Morelock Teddy E. , Rottinghaus George E. , Pompeu Daniel , Fritsche Kevin L. , Bogener Jennifer L. , Besch-Williford Cynthia L. , Lubahn Dennis B.
Published: February 2011

Prostate cancer possesses long latency periods and is responsive to dietary mediators, making it a target for phytochemoprevention. It has been reported that spinach consumption can reduce the incidence of prostate cancer leading our lab to look at structures of compounds present in spinach. We chose to study spinacetin and patuletin, two novel isoflavones found in spinach. We hypothesized that these spinach compounds would inhibit prostate cancer in vitro in the mouse prostate cancer cell line, TRAMP-C2, and that a spinach-containing diet would reduce cancer incidence in our TRAMP mouse model.

Methods: We first isolated a crude spinacetin-containing fraction and patuletin-containing fraction from whole spinach leaves using HPLC column purification. A further purified extract was also isolated for each compound. Using these extracts we determined the effect of the spinach compounds on growth of TRAMP-C2 cells, and the effect that they have on the concentration of Gli1, an indicator of hedgehog signaling, as measured by RT-PCR and a Gli1-luciferase reporter assay. We also tested ground dried spinach at 0.2% and 2% incorporated into a casein-based diet fed to B6/FVB TRAMP mice, and then evaluated the development of prostate cancer histologically.

Results: The extracts, each containing 0.1% spinacetin or patuletin, both inhibit prostate cancer cell growth in vitro, with the patuletin extract inhibiting approximately 30% and the spinacetin extract inhibiting nearly 50%. In addition, the purified compounds each inhibited Gli1 expression in both TRAMP-C2 (as measured by RTPCR) and Shh Light II cells (as measured by luciferase assay), with patuletin having an effect at 300nM and spinacetin at 1μM. The 2% spinach diet led to a 50% decrease in the incidence of well-differentiated carcinoma, but had no apparent effect on the more aggressive poorly-differentiated carcinoma. In conclusion, spinach and its compounds are capable of inhibiting prostate cancer growth and incidence in in vitro and in vivo mouse models.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5685.
Abstract 5688: Chemopreventive potential of ‘jamun’ (Indian blackberry) against estrogen-mediated mammary carcinogenesis
Authors: Aqil Farrukh , Jeyabalan Jeyaprakash , Gupta Akash , Sharma Ram J. , Sidana Jasmeen , Singh Inder P. , Gupta Ramesh C.
Published: February 2011

Colored fruits, particularly berries, are emerging as highly chemoprotective because of their antioxidant, anti-proliferative and anti-inflammatory activities. In this study, we investigated chemoprotective potential of Eugenia jambolana Lam., commonly known as ‘jamun’ or Indian blackberry. Jamun is widely used as a fruit in India and several other Asian countries, besides its use in the treatment of various ailments, including diabetes mellitus. Anthocyanin pigments in the jamun were extracted with acidic ethanol, and the crude anthocyanin extract was purified by ethyl acetate partitioning, amberlite XAD7/HP20 column chromatography, followed by Sephadex LH-20 column Chromatography. Anthocyanin content in jamun pulp powder was found to be 0.08% by HPLC-PDA (at 520nm). Upon hydrolysis, the jamun extract yielded five anthocyanidins, namely delphinidin (20.3%), cyanidin (6.6%), petunidin (24.6%), peonidin (2.8%) and malvidin (44.2%) as detected by HPLC and confirmed by mass spectral analysis. The jamun extract had high antioxidant potential as reflected by ABTS scavenging (IC50, 12 µg/ml), DPPH scavenging (IC50, 110 µg/ml), and ferrous ions-chelating activities (IC50, 50 µg/ml). In vivo chemopreventive effect of jamun was investigated using the estrogen-mediated ACI rat mammary tumorigenesis model. Groups of female rats were given control (AIN 93M) diet or diet supplemented with jamun pulp powder (5%, w/w). Two weeks later, one half of the animals from each group were treated with subcutaneous silastic implants of 17β-estradiol (1.2 cm; 9 mg). Diet and water were provided ad libitum. Twelve weeks later immediately before the appearance of mammary tumors, all groups were euthanized and blood and mammary tissue were collected. No significant difference was observed in body weight gain and diet intake when compared with control, suggesting that jamun diet was well tolerated. Estrogen treatment resulted in substantial (30-fold) elevation of the plasma prolactin, a key factor in mammary tumorigenesis. The plasma prolactin levels were significantly offset by jamun-supplemented diet. To determine molecular mechanisms of its chemopreventive effects, mammary tissues were analyzed for the expression of cyclin D1 and estrogen receptor alpha (ERα). Western blot analysis showed that jamun diet significantly down-regulated the levels of both cyclin D1 and ERα. Together, these data suggest that jamun contains compounds with high antioxidant and antiproliferative activities, suggesting that consumption of jamun fruit may be useful in the prevention/treatment of breast cancer (Supported from CA-125152 and Agnes Brown Duggan Endowment).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5688.