bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 419: Periostin activates integrin alpha5/beta1 through AKT-dependent pathway in invasion of cholangiocarcinoma
Authors: Thuwajit Chanitra , Utispan Kusumawadee , Sonongbua Jumaporn , Thuwajit Peti
Published: July 2012

Cholangiocarcinoma (CCA), a cancer arising from bile duct epithelial cells, is a serious health problem in Thai people. It is a progressive tumor with high metastatic potency. Recently, our group has found that periostin, an extracellular matrix protein, mainly produced from stromal activated fibroblasts of CCA has strong impact to induce cancer cell invasion. This work aims to investigate specific integrins which are utilized by periostin to drive invasion of CCA cells. The activated intracellular signal transduction pathway is also explored. Seven Thai patients-derived CCA cell lines were investigated their integrin expression patterns by real time PCR. The results indicated high level of integrin alpha6 in almost all cell lines. In addition, integrin alpha5 was also detected in not only CCA cell lines but also in immortalized non-tumorigenic biliary epithelial cell. For beta subunit integrin, the result revealed high expression levels of integrins beta1 and beta4 in CCA and non-tumorigenic cells. These results implied high level of integrins alpha5/beta1 and alpha6/beta4 in CCA cells. Flow cytometry and immunocytochemistry analysis confirmed intact molecules of these 2 integrin receptors on the membrane of M213 CCA cell line. Cell adhesion on periostin-coated surface was significantly decreased after integrin alpha5/beta1, but not alpha6/beta4, was blocked with the corresponding neutralizing antibodies. This result indicated that CCA cells preferred to use integrin alpha5/beta1 to bind with periostin. Moreover, cells treated with a neutralizing antibody against integrin alpha5/beta1 showed attenuated effect of periostin-induced invasion as similar to cells exposed to siRNA against integrin alpha5. Furthermore, we found that integrin alpha5-knocked down cells had decreased level of intracellular pAKT compared to negative control cells after activation with periostin. Taken these results together, it is likely to say that periostin activates CCA invasion through integrin alpha5/beta1 and AKT-dependent signal transduction pathway. This study suggests fibroblast-derived periostin, the stromal cell-derived substance, in promotion of CCA progression. Importantly, the obtained data highlight the potential of using the mechanism underlying stroma-driven cancer progression as an alternative target in the treatment of CCA patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 419. doi:10.1158/1538-7445.AM2011-419
Abstract 4190: ADAM23: Biomarker for nonmelanoma skin cancer disease progression
Authors: Peng Lisan S. , Regan Suzanne
Published: July 2012

The ADAMs (A Disintegrin and Metalloproteinase) comprise a family of multidomain transmembrane and secreted proteins involved in cytokine and growth factor release, proteolysis and cell adhesion. Multiple family members have been shown to play a role in cancer formation and disease progression. Decreased ADAM23 expression has been demonstrated in human breast, colon, gastric, head and neck, brain and pancreatic cancers and is believed to be associated with a more malignant or metastatic phenotype. Substantially more than 1 million cases of non-melanoma skin cancer (NMSC) occur annually in the United States according to the American Cancer Society. Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the two major types of NMSC and most are related to chronic sun exposure. We have demonstrated by microarray analysis that ADAM23 expression is decreased in human keratinocytes chronically irradiated with a solar-simulated light source. Using a human SCC skin carcinogenesis model, we have demonstrated that decreased ADAM23 expression correlates with disease progression. Preliminary immunohistochemical analysis of human SCC samples also demonstrates decreased ADAM23 expression. We believe that ADAM23 may serve as a biomarker of human skin SCC disease progression. This may be important for earlier detection and for the possible development of targeted therapy that may serve as an alternative to potentially disfiguring surgical treatment.

This work was supported in part by PHS grant CA27502 and CA23074 from the National Cancer Institute and the National Institutes of Health. It was also supported in part by start-up funds supplied by the Department of Medicine at the University of Arizona School of Medicine.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4190. doi:10.1158/1538-7445.AM2011-4190
Abstract 4191: Prognostic impact of phosphohistone H3 in cutaneous nodular melanoma
Authors: Ladstein Rita G. , Bachmann Ingeborg M. , Straume Oddbjorn , Akslen Lars A.
Published: July 2012

Aims: The mitotic marker Phosphohistone H3 (PHH3) is considered to facilitate counting of mitosis. The aim of this study was to evaluate the prognostic significance and strength of PHH3 expression in a series of nodular cutaneous melanoma in comparison with other proliferation markers.

Materials and methods: Standard sections of paraffin embedded tumor tissue from 345 cases of cutaneous melanoma of the nodular type were examined by immunohistochemistry, and PHH3 staining of tumor cells were recorded in an area of 1 mm2.

In 92 cases, data on mitotic count and Ki-67 expression was available for comparison. The mitotic count was assessed on standard H&E as number of mitoses per mm2, the immunohistochemical staining of Ki-67 was given as a percentage of positive tumour cells.

Results: Increased PHH3 was strongly associated (p<0.001) with increased tumor thickness, presence of ulceration and tumor necrosis. Furthermore, high expression of PHH3 was correlated with increased mitotic count (p<0.001) and high Ki-67 expression (p=0.001). Univariate survival analysis showed significantly worse outcome in the cases with high PHH3 count (p<0.001). Increased PHH3 and tumor thickness were significant prognostic factors in multivariate survival analysis when included together with ulceration. In multivariate survival analysis of the subset of 92 cases, high PHH3 was a stronger predictor of patient outcome than Ki-67 expression and mitotic count.

Conclusion: In this series of nodular melanomas, high PHH3 count was a significant predictor of poor prognosis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4191. doi:10.1158/1538-7445.AM2011-4191
Abstract 4196: MSH3 mediates sensitization of colorectal cancer cells to cisplatin, oxaliplatin and a poly(ADP-ribose) polymerase inhibitor
Authors: Takahashi Masanobu , Koi Minoru , Balaguer Francesc , Boland C. Richard , Goel Ajay
Published: July 2012

Introduction:The MSH3 gene is one of the DNA mismatch repair (MMR) genes that has undergone somatic mutation frequently in MMR-deficient cancers. MSH3, together with MSH2 forms the MutSβ heteroduplex, which interacts with interstrand crosslinks (ICLs) induced by drugs such as cisplatin and psoralen. However, the precise role of MSH3 in mediating the cytotoxic effects of ICL-inducing agents remains poorly understood. MethodsIn this study, we first examined the effects of MSH3 deficiency on cytotoxicity caused by cisplatin and oxaliplatin, another ICL-inducing platinum drug. Results: Using isogenic HCT116-derived clones in which MSH3 expression is controlled by shRNA expression in a tet-off system, we discovered that MSH3 deficiency sensitized cells to both cisplatin and oxaliplatin at clinically relevant doses. Interestingly, siRNA-induced down-regulation of the MLH1 protein did not affect MSH3-dependent toxicity of these drugs, indicating that this process does not require participation of the canonical MMR pathway. Furthermore, MSH3-deficient cells maintained higher levels of pH2AX after oxaliplatin treatment in comparison to MSH3-proficient cells, suggesting that MSH3 plays an important role in repairing DNA double strand breaks (DSB). This role of MSH3 was further supported by our findings that MSH3-deficient cells were sensitive to olaparib, a Poly(ADP-ribose) polymerase inhibitor. Moreover, the combination of oxaliplatin and olaparib exhibited more than 10-fold increase in toxicity compared to either treatment individually. Conclusion:Collectively, our results provide novel evidence that MSH3 deficiency contributes to the cytotoxicity of platinum drugs through deficient DSB repair. These data lay foundation for the development of effective prediction and treatments for cancers with MSH3 deficiency.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4196. doi:10.1158/1538-7445.AM2011-4196
Abstract 4197: A DNA damage checkpoint response to unrepaired ultraviolet radiation-induced lesions which is defective in melanoma
Authors: Wigan Matthew , Pavey Sandra , Brooks Kelly , Giles Nichole , Burgess Andrew , Sturm Rick , Gabrielli Brian
Published: July 2012

Ultraviolet radiation (UVR) is a major environmental risk factor in the development of skin cancer. Here we describe a G2 phase cell cycle checkpoint response to suberythemal doses of UVR that is defective in a majority of melanoma cell lines tested. The majority of cells in the basal layer of the epidermis are quiescent, and exposure to suberythemal doses of UVR produces not only DNA damage but also provides a mitogenic stimulus to drive cells into the cell cycle. The majority of UVR-induced DNA lesions are rapidly repaired by NER mechanisms, but a small number of DNA lesions fail to be repaired during G1 phase and are encountered by the replication fork during S phase. This triggers Werner helicase (Wrn) dependent lesion bypass, allowing replication to continue relatively unhindered, but producing gaps in the newly replicated DNA strand opposite the lesions. These single stranded DNA gaps recruit replication protein A (RPA) and components of the ATR-Chk1 checkpoint signaling responsible for the G2 phase arrest observed. The RPA foci also co-localise components of the error free RAD18-RAD51 post replication repair pathway which are essential for repair of the gaps and checkpoint signaling. This checkpoint mechanism ensures detection and repair of all UVR induced DNA damage before proceeding into mitosis. Loss of this checkpoint response increases the rate of UVR induced mutation. Thus this checkpoint response is critical for maintaining genomic stability in the epidermal melanocytes and keratinocytes, and loss of this checkpoint mechanism may account for the increased UVR signature DNA mutations found in melanomas.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4197. doi:10.1158/1538-7445.AM2011-4197
Abstract 4198: Mismatch repair polymorphisms and breast cancer risk in the Metropolitan New York Breast Cancer Family Registry
Authors: Kappil Maya A. , Delgado-Cruzata Lissette , Liao Yuyan , Terry Mary-Beth , Santella Regina M.
Published: July 2012

Suboptimal DNA repair capacity is believed to contribute to genomic instability and, thereby, onset of carcinogenesis. In fact, deficient repair has been reported to account for up to a five-fold increase in breast cancer risk. Major cancer susceptibility genes involved in repair, including BRCA1 and BRCA2 among breast cancer cases, have been identified. However, mutations in these genes are thought to account for only 5-10% of familial cases. Additional genetic susceptibility factors may play a role in the remaining cases, including polymorphisms in DNA repair pathway genes. Microsatellite instability, a commonly observed marker of mismatch repair (MMR) defects, has been observed in skin samples from breast cancer patients, suggesting a putative role for MMR in breast cancer. In this study, we investigated polymorphisms in mismatch repair genes and their association with breast cancer risk among participants of the Metropolitan New York Registry of Breast Cancer Families (N=744). Of the 313 sister-sets included in the registry, 306 sister-sets consisted of sisters discordant for disease. A total of twelve SNPs were chosen and assayed using Taqman SNP genotyping kits from Applied Biosystems. Using conditional logistic regression, an association with breast cancer was observed for two of the twelve SNPs assayed. A significant association with breast cancer risk was observed for MutY (H335Q,C/G) while a borderline association was observed for MSH2 (IVS12-6, T/C): OR = 2.24 (1.11-4.52) and OR = 1.71 (0.99-2.95), respectively. Future studies will focus on replicating these findings in a larger study population.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4198. doi:10.1158/1538-7445.AM2011-4198
Abstract 4202: Hair follicles disruption leads to enhanced UVB-induced cutaneous inflammation and basal cell carcinoma development
Authors: Xu Jianmin , Athar Mohammad , Kopelovich Levy
Published: July 2012

Hairless mice carrying homozygous mutations in hr gene manifest disrupted hair follicles (HFs) and develop more squamous cell carcinomas (SCCs) than their haired littermates, suggesting that HFs act as tumor suppressor for cutaneous SCCs. However, the role of HFs in the pathogenesis of BCCs remains elusive. Here, we show that HF disruption alters susceptibility to both BCCs and SCCs. For this, we bred ptch+/-/C57BL6 mice with SKH-1 hairless mice followed by brother-sister crossing to get F2 homozygous mutant or wild-type mice. These animals were UVB-irradiated for 44 weeks. UVB-induced inflammation was less pronounced in shaved haired than in hairless mice. In hairless mice, inflammatory infiltrate was histologically associated around the epidermal cyst and rudimentary HFs suggesting that HF disruption enhances UVB-induced inflammation. Tumor onset in hairless mice begins 10 weeks earlier than in shaved haired littermates. 100% of hairless developed >15 tumors/mouse after 32 weeks while haired mice developed <3 tumors/mouse following 44 weeks irradiation. The tumor spectrum in hairless and haired animals was also different. Spindle cell carcinomas only appeared in haired mice. Hairless animals developed more squamous papillomas and SCCs. The incidence of BCCs was significantly higher in hairless animals (p<0.001). UVB-induced skin tumors in hairless mice were more aggressive than those in haired shaved littermates. Molecular typing of these tumors showed decreased E-cadherin expression and enhanced mesenchymal proteins, snail, slug, fibronectin and vimetin. These data suggest that the disruption of HF enhances susceptibility to epidermal carcinogenesis by augmenting inflammation and epithelial-mesenchymal transition.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4202. doi:10.1158/1538-7445.AM2011-4202
Abstract 4206: Tumorigenic polyploid cells contain elevated levels of reactive oxygen species and are selectively targeted by antioxidant treatment
Authors: Roh Meejeon , Van der Meer Riet , Abdulkadir Sarki
Published: July 2012

Polyploidy has been linked to the tumorigenicity mainly due to the chromosomal aberrations. Elevated reactive oxygen species (ROS) generation, on the other hand, has also been associated with oncogenic transformation in most cancer cells. However, a possible link between ploidy and ROS is largely not known. Here we have explored the role of ROS in the tumorigenicity of polyploid cells. We show that polyploid prostate and mammary epithelial cells contain higher levels of ROS due to their higher mitochondrial contents. ROS levels and mitochondrial mass are also higher in dihydrocytochalasin B (DCB)-induced polyploid cells, suggesting that higher levels of ROS observed in polyploid cell is due to cytokinesis failure. Interestingly, polyploid cells were more sensitive to the inhibitory effect of the antioxidant, N-Acetyl-L-cysteine (NAC), than control diploid cells. Treatment of polyploid/diploid cells with NAC led to the selective elimination of polyploid cells over time and abrogated the tumorigenicity of polyploid cells. This was partially mediated via the Akt signaling pathway. We next explored a possible role for ROS in promoting chromosomal instability by analyzing the effects of ROS on the mitotic stage of the cell cycle. Enhancing ROS levels by treatment of cells with hydrogen peroxide delayed not only entry into and but also exit from mitosis. Furthermore, increasing ROS levels significantly increased taxol resistance. Our results indicate that increased ROS in polyploid cells can contribute to tumorigenicity and illuminates therapeutic potential of antioxidant by selectively targeting the tumorigenic polyploidy cells and reversing taxol resistance.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4206. doi:10.1158/1538-7445.AM2011-4206
Abstract 4207: DHA enhances genotoxic stress in prostate cancer cells through suppression of NF-κB
Authors: Cavazos David A. , deGraffenried Linda A.
Published: July 2012

Excess levels of omega-6 fatty acids, commonly consumed in Western diets, are heavily implicated in contributing to prostate cancer incidence and tumor cell proliferation. Omega-6 fatty acids may promote worse outcome through the chronic production of eicosanoids that promote inflammation and oxidative stress. As omega-3 fatty acids competitively interact with some of the same rate-limiting enzymes to diminish inflammation and oxidative stress, epidemiologic studies have sought to determine if diets high in omega-3 fatty acids may impart beneficial effects on prostate cancer rates and progression. Pre-clinical observations indicate that omega-3 fatty acids suppress prostate tumor cell growth and induce cancer cell death, supporting a beneficial role of omega-3 fatty acids in delaying time to PSA failure and reducing the aggressiveness of advanced prostate cancer. As omega-3 fatty acids possess known pro-oxidant and antioxidant properties, we investigated the effects of docosahexaenoic acid (DHA-22:6n-3) in modulating oxidative DNA damage in normal and prostate cancer cells. Preliminary data demonstrates that prostate cancer cells (LNCaP) pretreated with DHA and pulsed with physiologic levels of H2O2 encounter a sustained G2 checkpoint arrest and exhibit decreased colony formation potential when compared to normal prostate epithelial cells (PrEC). LNCaP cells pulsed with 32 uM H2O2 exhibit DNA breaks associated with translocation of NF-κB into the nucleus, whereas pretreatment with DHA precluded NF-κB translocation, selectively sensitizing LNCaP cells, but not PrEC, to cell death. Further, DHA suppresses degradation of the NF-κB inhibitor, IκB, and attenuates NF-κB transcriptional activity as well as expression of the NF-κB downstream target, survivin. To conclusively demonstrate the critical role of NF-kB signaling in LNCaP cells after exposure to H2O2, we induced a 50% knockdown of p65 by siRNA and observe a complete ablation of colony formation relative to scrambled siRNA control vector. Here we describe one potential mechanism by which DHA may selectively increase genotoxicity in prostate cancer cells after exposure to oxidizing agents, ultimately setting the stage for Phase II clinical trials.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4207. doi:10.1158/1538-7445.AM2011-4207
Abstract 4210: Oxidative stress, DNA damage, and apoptosis mediated by arsenic trioxide in lung carcinoma cells
Authors: Walker Alice M. , Stevens Jacqueline J. , Tchounwou Paul B.
Published: July 2012

Lung cancer is one of the most lethal and common of cancers in the world, causing up to 3 million deaths annually. Arsenic trioxide (ATO) has been used in the treatment of relapsed/refractory acute promyelocytic leukemias. However, its effects on lung cancer are not known. We hypothesize that ATO may also have a bioactivity against lung cancer, and its mechanisms of action may involve apoptosis, DNA damage and changes in stress-related proteins in lung cancer cells. Using lung cancer (A549) cells as test model, mthe effects of ATO were examined by 6-diamidine-2 phenylindole (DAPI) nuclear staining for apoptosis, commet assay for genotoxicity ane western blotanalysis for stress protein (Hsp 70 and cfos) expression. Morphological changes of apoptosis (condensed chromatin and apoptotic bodies) were observed with DAPI and cell shrinkage and membrane blebbing without DAPI at 4 and 6µg/ml of ATO. The comet assay data revealed that DNA damage was significant as indicated by increased of the precent of DNA damage, tailmoment and tail length. There was significant increase in Hsp70 expression and significant decrease in cfos in ATO-treated cells compared to controls. ATO is cytotoxic to lung cancer cells and its toxicity is mediated via oxidative stress and DNA damage leading to apoptosis. However, further studies are warranted to understand its specific molecular mechanisms of toxicity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4210. doi:10.1158/1538-7445.AM2011-4210
Abstract 4211: p85alpha mediates p53 K370 acetylation by p300 and regulates its promoter-specific transactivity in the cellular UVB response
Authors: Song Lun , Gao Ming , Dong Wen , Hu Meiru , Li Jingxia , Shi Xiaoyan , Hao Yi , Li Yi , Huang Chuanshu
Published: July 2012

Inducible acetylation of p53 at lysine residues has a great impact on regulating the transactivation of this protein, which is associated with cell growth arrest and/or apoptosis under various stress conditions. However, the factor(s) for regulating p53 acetylation remains largely unknown. In the current study, we have shown that p85α, the regulatory subunit of PI-3K, plays a critical role in mediating p53 acetylation and promoter-specific transactivation in the UVB response. Depletion of p85α in mouse embryonic fibroblasts (MEFs) significantly impairs UVB-induced apoptosis as well as p53 transactivation and acetylation at Lys370 (Lys373 of human p53); however, the accumulation, nuclear translocation and phosphorylation of p53 are not affected. Interestingly, p85α binds to p300, promotes the p300-p53 interaction and the subsequent recruitment of the p53/p300 complex to the promoter region of the specific p53 target gene in response to UVB irradiation. Moreover, ablation of p53 acetylation at Lys370 by site-directed mutagenesis dramatically suppresses UVB-induced expression of the specific p53-responsive gene as well as cell apoptosis. Therefore, we conclude that p85α is a novel regulator of p53-mediated response under certain stress conditions, and targeting the p85α-dependent p53 pathway may be promising for cancer therapy.

Key Words: acetylation/ p85α/ p53/ p300/UVB radiation

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4211. doi:10.1158/1538-7445.AM2011-4211
Abstract 4213: Defining the role of NF-kB as a target for omega-3 fatty acids in prostate cancer
Authors: Whelan Kaitlin A. , Cavazos David , deGraffenried Linda A.
Published: July 2012

Background: Docosahexaenoic acid (DHA), an omega-3 fatty acid, has been shown to enhance anticancer chemotherapies, but the specific mechanisms by which it promotes its anti-cancer effects remain unclear. Recent studies from our laboratory suggest that one important mechanism may be through modulation of NF-κB activity. NF-κB can alter cells by promoting cell proliferation and inflammation, inhibiting apoptosis, and facilitating metastasis. Preliminary data indicate a strong correlation between p65 retention in the cytoplasm and response to omega-3 fatty acids under conditions of androgen deprivation and/or oxidative stress. We hypothesize that regulation of p65 localization in response to cellular stress is an important mechanism by which DHA sensitizes prostate cells to anti-cancer therapies.

Methods: To elucidate the relationship between DHA, NF-κB and prostate cancer, we created a stable LNCaP cell line with constitutively active NF-κB, using a shRNA plasmid to knockout IκBα, the inhibitory protein retaining p65 in the cytoplasm. shRNA was stably transfected into LNCaP cells under G418 drug selection, and NF-κB activity assessed by luciferase reporter assays.

Results: NF-κB activity in the shRNA IκBα knockout clones was four times greater than that in the vector only control clones. Preliminary data suggest that DHA is not as effective at sensitizing cells to therapeutic agents in cells expressing constitutively active NF-κB due to IκBα inhibition compared to cells expressing normally regulated NF-κB. Studies are on-going to further define the role of NF-κB cellular localization in mediating the anti-cancer effects of DHA in prostate cells.

Conclusions: Our preliminary data indicate that cellular localization of the p65 subunit of NF-κB is an important mechanism by which the omega-3 fatty acids DHA sensitize prostate cells to anti-cancer therapies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4213. doi:10.1158/1538-7445.AM2011-4213
Abstract 4217: The anti-malarial compound artesunate induces reactive oxygen species-dependent killing of breast cancer cells
Authors: Greenshields Anna L. , Hoskin David W.
Published: July 2012

Introduction: Artesunate is a semi-synthetic derivative of artemisinin, a natural compound from the herb Artemisia annua L. Artemisinin has been used in traditional Chinese medicine while artesunate has recently been used as an anti-malarial drug. Artesunate is also cytotoxic to human cancer cells. Since the use of artesunate as an anti-malarial agent is associated with few adverse effects, artesunate may represent a less toxic alternative to conventional chemotherapy. This study investigates the cytotoxic effect of artesunate on breast cancer cell lines and the mechanism(s) underlying its activity.

Methods and Results: Artesunate exhibited a time- and dose-dependent cytotoxic effect on all breast carcinoma cell lines examined (MCF-7, T47D, SK-BR-3, MDA-MB-231, MDA-MB-468). Further examination of MDA-MB-468 cells using Oregon Green-488 and Annexin-V-FLUOS/propidium iodide staining indicated that artesunate had an anti-proliferative effect that was associated with apoptosis induction. Cell cycle arrest occurred in the G2 phase, and was evident as early as 24h after artesunate treatment. Artesunate-induced apoptosis was low in normal fibroblasts at concentrations cytotoxic to breast cancer cells, although fibroblast proliferation was inhibited. DiOC6 staining revealed dose-dependent destabilization of the mitochondrial membrane in artesunate-treated MDA-MB-468 cells. Artesunate-treated MDA-MB-468 cells also displayed cytosolic cytochrome c and PARP cleavage, as demonstrated by Western blotting, which was consistent with apoptosis induction. Pretreatment with reduced glutathione rescued MDA-MB-468 cells from artesunate-induced apoptosis, indicating that reactive oxygen species (ROS) mediate artesunate-induced cytotoxicity. In addition, MDA-MB-468 cells that were pretreated with holotransferrin showed increased killing by artesunate, suggesting that iron promotes artesunate-mediated apoptosis. Induction of the endoplasmic reticulum stress pathway in artesunate-treated cells was demonstrated by Western blotting, suggesting involvement of this apoptosis-inducing pathway in artesunate-mediated cytotoxicity.

Conclusions: These data show that artesunate causes reactive oxygen species-dependent induction of apoptosis in breast cancer cells and therefore warrants further investigation as a possible treatment for breast cancer.

Supported by NSERC and the Canadian Breast Cancer Foundation-Atlantic Region

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4217. doi:10.1158/1538-7445.AM2011-4217
Abstract 4218: Guggulsterone controls isomer-specifically TPA-induced MMP-9 expressions of MCF-7 cells: Identification of the cooperative combination of guggulsterone isomers in inhibition of breast cancer invasiveness
Authors: Kim Jong-Suk , Noh Eun-Mi , Kim Jeong-Mi , Lee Young-Rae , Youn Hyun Jo , Jung Sung Hoo , Kim Soo Mi , Park Jinny
Published: July 2012

Guggulsterone [4,17(20)-pregnadiene-3,16-dione], a constituent of Commiphora mukul, is used to treat obesity, diabetes, arthritis, and atherosclerosis. Recently it has been known that guggulesterone isomers (trans or cis) show isomer-specificity in their antileukemic activities in leukemia cells. Here, we investigated whether guggulsterone isomers differently control 12-O-tetradecanoylpho-bol-13-acetate (TPA)-induced MMP-9 expression, and then the combination of these isomers cooperatively inhibits breast cancer invasiveness. Cis-guggulsterone inhibited TPA-induced MMP expression through blocking NF-κB signaling, whereas trans-guggulsterone through blocking MAPK/AP-1 signaling. Cis-guggulsterone was the more potent than trans-guggulsterone in inhibition of TPA-induced MMP-9 expression and cell invasion of MCF-7 cells. Furthermore, we found that the combination of these isomers showed addictive effects on inhibition of cell invasion of MCF-7 cells. These results suggest that guggulesterone controls isomer-specifically TPA-induced MMP-9 expressions and cell invasions of MCF-7 cells. This study is the first to show that combination of guggulsterone isomers might be known as a potential strategy for the medical treatment of breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4218. doi:10.1158/1538-7445.AM2011-4218
Abstract 4222: Induction of apoptosis and cell cycle arrest in renal cancer cells by phenethyl isothiocyanate (PEITC) and the mechanisms involved
Authors: Khan Maruf H. , deGraffenried Linda A. , Sanders Bob G. , Ciolino Henry P.
Published: July 2012

Background: Renal Cell Carcinoma (RCC) has low 5 year survival rate and is resistant to radiation and chemotherapy. Phenethyl Isothiocyanate (PEITC) is a naturally occurring phytochemical that has a variety of anti-cancer properties. Here we explore two anti-cancer properties of PEITC: induction of apoptosis and induction of cell cycle arrest in RCC cell lines and the underlying mechanisms.

Methods: We used two human RCC cell lines Caki-1 and Caki-2. Survival and cell proliferation was assayed using Calcein AM. Annexin V staining was used to measure apoptosis. Caspase-3/7 induction was measured using a fluorescent substrate. Cell Cycle was studied using Propidium Iodide staining. DNA damage was determined using H2AX-γ antibody. Protein expression and phosphorylation was determined using immunoblotting.

Results: PEITC significantly reduced survival of Caki-1 and Caki-2 cells and inhibited their proliferation as determined by Calcein AM. 15 and 20 μM PEITC induced apoptosis (revealed by Annexin V staining) in both cell lines and induced caspase-3/7 activity. Western blot analysis revealed caspase-8, caspase-9 and Bid cleavage suggesting that the apoptosis is mediated through the extrinsic pathway. Lower doses (up to 10 μM) arrested Caki-1 cells in G2/M phase, and this was associated with an increase p38 and MK2 (Thr334) phosphorylation (as revealed by Western Blot). The p38 inhibitor SB203850 inhibited this G2 arrest induced by PEITC. In order to determine if DNA damage was responsible for the apoptosis and G2 arrest, we used an antibody to H2AX-γ phosphorylation. 15 and 20 µM treatment resulted in increased H2AX-γ phosphorylation, but this was completely blocked by caspase-3 inhibitor.

Conclusion: PEITC induces apoptosis in Caki-1 and Caki-2 cells by a mechanism that likely involves the extrinsic pathway. We will use immunoblotting and siRNA to determine which of the extrinsic receptors (DR4, DR5, TRAIL or FAS) is responsible for this apoptosis induction. PEITC does not cause direct DNA damage to the cells; the observed DNA damage is a result of the apoptotic process and is blocked by caspase-3 inhibitors. PEITC induces G2/M arrest in Caki-1 cells and the mechanism is dependent on p38 phosphorylation which activates MK2. Inducing cell cycle arrest and apoptosis may play an important role in the anti-cancer properties of PEITC. Fully understanding the mechanism by which PEITC induces apoptosis and cell cycle arrest in RCC cells may lead to development of novel chemotherapeutic drugs against RCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4222. doi:10.1158/1538-7445.AM2011-4222
Abstract 4223: Possible usefulness of spirulina platensis for supression of some cases of hepatocellular carcinoma, multiple case study
Authors: Hafez Raghda A. , Basha Osama M. , El Ayoty Yassin M. , Sadeq Refaat A. , Dawood Haitham
Published: July 2012

Backgrownd and study aims; One of the most frequent carcinoma through the world is hepato cellular carcinoma (HCC). It is rapidly fatal with a life expectancy of about 6 months from the time of diagnosis. The disease is more prevalent in parts of Africa and Asia with a strong etiological association with viral hepatitis, haemochromatosis, known carcinogen and toxins. There are many therapeutic options for HCC including; surgical operations, chemotherapy, radiofrequency, immune therapy and gene therapy. The use of natural products as drugs is gaining increasing interest especially due to reduced side effects, if any. In this study, we followed up hepatic patients with HCC, taking hot water extract of sterilized blue green alga, spirulina platenesis. Seven volunteers with cirrhotic liver resulting from chronic viral C hepatitis that had developed HCC were followed up in this work. All available investigations including laboratory and imaging facilities were done before starting the study and repeated monthly for follow up during the study.Results; After 10-15 months, patients are still alive, showing an improvement in the general condition with an obvious regression of the tumor size as well as, better liver functions. Also no obvious side effects were detected during the study.Conclusion; These observations may direct our attentions towards the possibility that the “water extract of sterilized blue green algae; spirulina platenesis” may be of therapeutic value in treatment and/or amelioration of symptoms of hepato cellular carcinoma especially in cirrhotic patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4223. doi:10.1158/1538-7445.AM2011-4223
Abstract 4226: Curcumin induced CaSR stimulates calpain autolysis in colon cancer
Authors: Singh Vinay K. , Kelly Jacqueline C. , MacLeod R John , Jia Zongchao
Published: July 2012

Colon cancer is the fourth most common form of cancer in the United States and the third leading cause of cancer-related death in the Western world. Progression to colon cancer is distinguished with a loss of the colonic calcium sensing receptor (CaSR). It has been observed that calcium-dependent proteolytic enzyme, Calpain (Capn) overexpressed in colon cancer may contribute to its metastasis. We attempted to identify role of calcium sensing receptor CaSR on regulation of capn activity and its influence on calmodulin (CaM) homeostasis. We have also investigated the role of curcumin in activation of CaSR. Curcumin (1μM and 20μM) increases expression (qPCR) and protein (2-3 fold) of the CaSR in wild type intestinal cells (RKO; wild type APC, wild type β-catenin) and cells with truncated APC (HT-29, SW480). Transient transfection of siRNA (200 nM) duplex against CaSR reduced CaSR protein expression and prevented reduction of Capn activity after 3 mM Ca2+ challenge (340+/-24 Units, p<0.05 n=4). Western blotting of HT-29 cell lysates after 3 mM Ca2+ challenge demonstrated no change in amount of Calpain-4 (Capn4, small subunit of Capn essential for its activity) but a 6 fold increase in CaM. Bioinformatic analysis of Capn4 revealed a presence of putative CaM binding site. Using circular dichroism, isothermal titration calorimetry and nuclear magnetic resonance it was confirmed that Capn4 binds to CaM. This is a first report of its kind demonstrating interaction of two EF-hand proteins. Capn after 30 min incubation with CaM demonstrated a 3 fold increase in autolysed Capn and 5 fold reduction in 75 kDa large-subunit of Capn. CaM antagonists W7 or W13 (100 μM) prevented CaSR-mediated decrease in Calpain activity (p<0.05, n=4). We hereby conclude that curcumin will increase CaSR expression and that calcium will stimulate the CaSR to increase calmodulin in colonic adenocarcinoma to produce Capn autolysis which will reduce Capn activity. We speculate that CaSR-mediated reduction in Capn activity may be an important determinant of calcium chemoprevention of colon cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4226. doi:10.1158/1538-7445.AM2011-4226
Abstract 4227: Curcumin in cyclodextrin in liposome as a delivery vehicle against osteosarcoma
Authors: Dhule Santosh S. , Penfornis Patrice , Frazier Trivia , Walker Ryan , Tan Grace , He Jibao , John Vijay , Pochampally Radhika
Published: July 2012

The delivery of curcumin, a broad spectrum anticancer drug, has been explored in the form of liposomal nanoparticles to treat osteosarcoma. Osteosarcoma (OS) accounts for approximately 20% of all bone cancers and it develops during the period of rapid growth in adolescence. Anti-cancer potential of curcumin has not been fully explored in the form of nanoformulations against OS. The drug is water insoluble and an effective delivery route is through encapsulation in cyclodextrins followed by a second encapsulation in liposomes. Liposomal curcumin's potential evaluated against OS and breast cancer. The resulting 2-Hydroxypropyl-gamma-cyclodextrin/curcumin-liposome complex shows promising anticancer potential against cancer of mesenchymal and epithelial origin when tested against KHOS and MCF-7 cell lines with IC50 value of 5.4 and 10.2 µg/ml respectively. The anticancer potential of curcumin in the form of DCL (drug-in-cyclodextrin-in-liposome) preparation has been explored first time for OS. DMSO-curcumin (free drug) induced autophagic cell death in KHOS whereas liposomal curcumin initiates the caspase cascade that leads to apoptotic cell death in vitro and in vivo also. The in vivo study was performed using human osteosarcoma xenograft model in mice. Interestingly, liposomal curcumin was less toxic on normal cells. In this study, the objective to cause cancer cell death by apoptosis and not by autophagy was achieved through liposomal curcumin formulations alone.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4227. doi:10.1158/1538-7445.AM2011-4227
Abstract 423: Decipher the molecular mechanisms by which syndecan-1 in breast cancer stroma fibroblasts regulates extracellular matrix fiber organization and carcinoma cell motility
Authors: Yang Ning , Friedl Andreas
Published: July 2012

The cell surface proteoglycan syndecan-1 (Sdc1) is frequently induced in the stromal fibroblasts of invasive breast carcinomas. We have recently identified a striking correlation between stromal Sdc1 expression and extracellular matrix (ECM) fiber architecture, both In vivo (in human breast carcinoma samples) and in vitro. Bioactive, cell-free 3D ECMs generated from cultures of Sdc1-positive human mammary fibroblasts (HMF), termed ECM-Sdc1, showed an organized, aligned fiber architecture, which contrasted markedly with the random fiber arrangement seen in the ECM of Sdc1-negative HMFs (ECM-mock). We further demonstrated that aligned ECM fiber architecture was responsible for the enhanced directional migration and invasion of the breast carcinoma cells when seeded into the fibroblast-free ECM-Sdc1.

To decipher the molecular mechanisms responsible for the formation of an invasion-permissive ECM, a series of Sdc1 mutants was introduced into HMF. These include a heparan sulfate (HS) -deficient, a cytoplasmic domain (CD) deletion and a transmembrane domain (TMD) substitution mutant. Early experiments suggest that HS are required for the activity of Sdc1 in regulating ECM alignment, while TDM is dispensable.

Integrins play a key role in the assembly of the provisional fibronectin-rich ECM and Sdc1 has been shown to be an important regulator of integrin activity. Therefore, we have begun to investigate the the role of integrins in Sdc1-mediated ECM fiber alignment. HMF expresses various integrins, as determined by Western blotting and flow cytometry. Using siRNA oligos, we are targeting different integrin subunits including α4, α5, αV and β3 to determine, which integrins are responsible for Sdc1-dependent ECM fiber alignment and consequently the invasion-permissive properties of the ECM. A better understanding of the mechanisms governing ECM organization may lead to the development of novel stroma-targeted therapy for breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 423. doi:10.1158/1538-7445.AM2011-423
Abstract 4230: Anthocyanins from the fruit of Vitis coignetiae Pulliat exhibits anticancer effects on Hep 3B human hepatocelluar carcinoma cells xenografts in nude mice
Authors: Lu Jing Nan , Jeong Kim Min , Lee Won Sup , Yun Jeong Won , Kim Dong Chul , Lee Yun Koung , Jeong Jae-Hoon , Choi Yung Hyun , Kim GonSup , Ryu Chung Ho , Park Ock Jin , Shin Sung Chul
Published: July 2012

Vitis coignetiae Pulliat (Meoru in Korea) has been used as a folk remedy for inflammatory diseases and cancers. Our previous in vitro study suggested that anthocyanins from fruits of Vitis coignetiae Pulliat (AIMs) should have anti-cancer activities through suppression of NF-κB. Before in vivo study, we also confirmed with Hep3B human hepatocellular carcinoma cells that AIMs suppressed NF-κB-regulated gene products. Here, we investigated their effects on NF-κB-regulated gene products and cellular responses in Hep3B cell-originated tumors in athymic nude mice. Hep3B cells (1 × 106 cells/0.1 mL) were subcutaneously injected into the left flank of twelve athymic (nu/nu) male nude mice, and then the nude mice were randomly divided into two groups with six animals each. The first group of animals received intraperitoneal injection of 100 AL of 1:10 ratio of DMSO and normal saline, whereas animals of the second group received intraperitoneal injection of AIMs (5 μg/g of animal in 100 AL of 1:10 ratio of DMSO and normal saline) daily. The AIMs suppressed the tumor growth compared to control. AIMs suppressed Ki67 expression and intratumoral vessel density on immunohistochemical staining. In addition, Western blot and immunohistochemical staining revealed AIMs suppressed the NF-KB activation and NF-KB-regulated protein levels such as COX-2, XIAP, MMP-9, VEGF and ICAM which are related to cancer cell proliferation, survival, invasion and angiogenesis in Hep3B cell-originated tumors in athymic nude mice. However, the expressions of some NF-KB-regulated proteins were not significantly suppressed.

Taken together, this study indicates that the AIMs have anti-cancer effects on Hep3B cell xenografts at least in part through the inhibition of NF-κB activation and downstream proteins. This study provides evidence that AIMs might have anticancer effects on human hepatocellular carcinoma. [This study was supported by a grant from the National R&D Program for Cancer Control, Ministry for Health, Welfare & Family Affairs, Republic of Korea. (0820050).]

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4230. doi:10.1158/1538-7445.AM2011-4230