bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1601: Ethanol promotes chemically induced oral cancer in mice through activation of the 5-lipoxygenase pathway of arachidonic acid metabolism
Authors: Guo Yizhu , Wang Xin , Zhang Xinyan , Sun Zheng , Chen Xiaoxin Luke
Published: August 2012

Alcohol drinking is a known risk factor for oral cancer in humans. However, previous animal studies on the promoting effect of ethanol on oral carcinogenesis were inconclusive. It is necessary to develop an animal model with which the molecular mechanism of ethanol-related oral carcinogenesis may be elucidated in order to develop effective prevention strategies. In this study, mice were first treated with 4-nitroquinoline-1-oxide (4NQO, 100μg/ml in drinking water) for 8 weeks, and then given water or ethanol (8%) as the sole drink for another 16 weeks. During the experiment, 8% ethanol was well tolerated by mice. The incidence of squamous cell carcinoma (SCC) increased from 20% (8/41) to 43% (17/40; p<0.05). Expression of 5-lipoxygenase (5-Lox) and cyclooxygenase 2 (Cox-2) was increased in dysplasia and SCC of 4NQO-treated tongues, and further enhanced by ethanol. Using this mouse model, we further demonstrated that fewer cancers were induced in Alox5-/- mice, as were cell proliferation, inflammation, and angiogenesis in the tongue, as compared with Alox5+/+ mice. Interestingly, Cox-2 expression was induced by ethanol in knockout mice, while 5-Lox and leukotriene A4 hydrolase (LTA4H) expression and leukotriene B4 (LTB4) biosynthesis were dramatically reduced. Moreover, ethanol enhanced expression and nuclear localization of 5-Lox and stimulated LTB4 biosynthesis in human tongue SCC cells (SCC-15 and SCC-4) in vitro. In conclusion, this study clearly demonstrated that ethanol promoted 4NQO-induced oral carcinogenesis, at least in part, through further activation of the 5-Lox pathway of arachidonic acid metabolism.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1601. doi:1538-7445.AM2012-1601
Abstract 1604: Treatment with Pequi (Caryocar brasiliense Camb) fruit pulp oil decrease the DNA damage caused by chemical carcinogenesis in experimental model of lung cancer.
Authors: Colombo Natália B. , Parra Edwin Roger , koppe Grisolia César , Hage Marcia , Rangel Maristela P. , Capelozzi Vera Luíza
Published: August 2012

Background: It is well known that a daily consumption of foods that are rich in antioxidants prevents the oxidative damage caused by reactive species (ROS), including DNA damage, and can reduce the risk of cancer, atherosclerosis and other degenerative diseases. The pulp of Caryocar brasiliense Camb, most known as pequi, is a Brazilian fruit that has high levels of antoxidants properties, such as vitamin C, carotenoids, phenolic compounds like flavonoids, saponins and tannins, and essential oils. The aim of this study was to evaluate the action of the pequi oil in the DNA damage in experimental model of lung cancer induced by the urethane. Material and Methods: Male BALB/c mice (n=14) received by gavage 0,5μL/mg/day of pequi oil (CBC oil) during 75 days. After 15 days of the beginning of the gavage, 10 of these animals received two doses of 1,5g/kg intraperitoneal of urethane (Urethane + CBC oil). Urethane animals (n=4) were only submitted to two doses of 1,5g/kg intraperitoneal of urethane (urethane group). After these 75 days, lung tissues were submitted to histological and biochemical analysis by comet assay method to evaluated the DNA damage. The DNA damage was quantificate by image analysis. Results: The lung parenchyma from the urethane groups without oil and with oil showed neoplasic formations induced by the chemical carcinogenesis in contrast with oil control group. The image analysis of the comet assay showed a statistical significant diminish of the DNA damage cells in the urethane oil group when compared with urethane control group (p=0.001). The decreased DNA damage was very similar that we obtained in the oil control group. Conclusion: We conclude that the different antioxidant components found in the pequi oil diminish the DNA damage in the mouse lung after chemical carcinogenesis, suggesting that this type of strategies may have a greater impact in lung cancer treatment. Financial Support: FAPESP, CNPq

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1604. doi:1538-7445.AM2012-1604
Abstract 1605: α-cryptoxanthin supplementation inhibits the carcinogen-initiated and nicotine-promoted lung carcinogenesis in AJ mice by suppression of AKT activation
Authors: Iskandar Anita R. , Liu Chun , Ernst Hansgeorg , Choi Sang-Woon , Ausman Lynne , Wang Xiang-Dong
Published: August 2012

A pooled analysis from well-implemented cohort studies reported that increased dietary α-cryptoxanthin (BCX) intake, rather than α-carotene used in earlier human trials, is associated with reduced risk of lung cancer. Nonetheless, BCX efficacy on lung carcinogenesis has not been reported. In these studies, we examined the protective effects of BCX at different doses against lung carcinogenesis at the initiation and the promotion stages of the cancer development in male AJ mice. In the tobacco carcinogen 4-(methylnitrosamino)- 1-(3-pyridyl)-1-butanone [NNK]-initiated lung carcinogenesis model, we found a 52-63% reduction of lung tumor multiplicity in mice pre-treated with BCX at 0.2 and 2 mg kg BW-1 d-1, as compared to the NNK group (P<0.01). In contrast, BCX did not significantly alter the spontaneous lung tumor multiplcitiy in mice without the NNK treatment. Furthermore, in the NNK-initiated and nicotine-promoted lung cancer model, we found that nicotine treatment by intraperitoneal injections not only significantly induced emphysema, a risk for lung cancer, but also greatly increased lung tumor multiplicity of the NNK-treated mice. Remarkably, BCX at 2 and 4 mg kg BW-1 d-1 prevented the nicotine-induced pulmonary emphysema and decreased tumor multiplicity by 86-91% (P<0.01). BCX protective effect on carcinogenesis was associated with significant suppression of lung AKT activation measured by immunoblotting. BCX also reduced the emphysema-related IL-6 and early growth response-1 induction of mRNA levels measured by real-time PCR. Contrary to α-carotene reported in prior animal studies, BCX also induced the retinoic acid receptor-α mRNA. As measured by HPLC analysis, the concentrations of liver BCX were higher in the BCX supplemented mice, without alteration of the retinol concentrations. Our data suggest that BCX is a unique chemopreventive agent for lung cancer prevention, which is likely to be independent of its provitamin A activity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1605. doi:1538-7445.AM2012-1605
Abstract 1606: Antitumor effects of vitamin D in a carcinogen-induced mouse model of lung cancer
Authors: Mazzilli Sarah A. , Reid Mary E. , Seshadri Mukund , Bogner Paul N. , Foster Barbara A. , Johnson Candace S. , Trump Donald L.
Published: August 2012

Lung cancer accounts for the majority of cancer mortality in both men and women. It is critical to better understand the biology of lung cancer development as no preventive agents and few effective treatment options exist for lung cancer. Epidemiological studies indicate that low serum levels of 25(OH)D3 are associated with increased risk and poor prognosis of lung cancer. Calcitriol, the active metabolite of vitamin D, induces cell cycle arrest, apoptosis and differentiation in preclinical and clinical studies, has limited toxicity, and hence, is an attractive agent for chemoprevention. To investigate the preventive effects of vitamin D on lung squamous cell carcinoma (SCC), pre-clinical studies were conducted using a carcinogen-induced (CI) mouse model of lung SCC which uses N-nitroso-tris-chloroethylurea (NTCU) applied topically to the back of a SWR/J mouse twice weekly. Following ∼15 weeks of NTCU treatment, mice begin to develop bronchial epithelial hyperplasia and in time, progress through metaplasia, carcinoma in situ, and ultimately form lung SCC by approximately 35 to 40 weeks. We conducted a preliminary study investigating the effects of vitamin D on cancer progression in the CI model where animals received NTCU (80 mM/week). 12 week old female mice were randomized into one of three treatment groups: 1) vitamin D deficient diet (DD) (0IU D3 in the diet), 2) sufficient diet (SD) (2000IU/day D3 in the diet) and 3) SD with weekly intraperitoneal (IP) injections of calcitriol (80 ug/kg) (SD+D). Animals treated with NTCU on a DD, SD and SD+D had average serum 25(OH)D3 levels of 15, 70 and 75 nmol/L, respectively (normal range in mice is 70- 90 nmol/L). Preliminary histological evaluation at 12 weeks revealed bronchial epithelial hyperplasia in both the SD and SD+D groups. There were more advanced changes including hyperplasia, metaplasia and dysplasia in the DD mice. The histological evaluation of the DD mice at 24 weeks revealed even more advanced disease, in that most mice had developed lung SCC. The histological evaluation of the SD and SD+D groups at 24 weeks indicated the presence of bronchial epithelial hyperplasia, squamous metaplasia and dysplasia in all mice with some low level of carcinoma in situ. This study indicates that mice deficient in vitamin D develop disease at a more rapid rate suggesting that vitamin D status may play an important role in progression of lung SCC. Supported by NCCAM F31 AT006487 & R01-CA-067267.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1606. doi:1538-7445.AM2012-1606
Abstract 1608: Silibinin synergizes with histone deacetylase (HDAC) inhibitors in upregulating E-cadherin expression in non-small lung cancer (NSCLC) cells
Authors: Mateen Samiha , Raina Komal , Agarwal Chapla , Chan Daniel , Agarwal Rajesh
Published: August 2012

Lung cancer is the leading cause of cancer-related mortalities, and the 5-year survival rate of this malignancy remains at 15%. This feature is attributed primarily to the early metastasis of the disease within the organ and to distant sites that involves the epithelial-to-mesenchymal transition (EMT) of lung cancer cells. Aggressive cancer cells with EMT are characterized by loss of cell adhesion, repression of E-cadherin expression and increased cell mobility. NSCLC cells widely differ in their basal level of E-cadherin expression, which is epigenetically silenced in most of them due to deacetylation by histone deactylases. This suggests that inhibitors of HDACs would be useful in NSCLC control. Several HDAC inhibitors (HDACi) have shown potential in this regard, and are in clinical trials; however, their toxicity and cancer cell resistance are the limiting factors. Silibinin (Sb), a non-toxic chemopreventive agent, has shown strong efficacy against epithelial cancers including NSCLC, and previously, we have demonstrated that Sb alters HDAC enzymatic activity and protein levels in a total cellular extract of H1299 cells. Herein, we sought to determine the putative role of Silibinin, either alone or in combination with other HDACi in modulating E-cadherin levels in NSCLC cell lines including H1299 cells (epigenetically silent E-cadherin levels). Treatment with HDAC inhibitors, Trichostatin A [TSA] (0.33-1 µM) or SAHA (0.5-5 µM) led to a dose-dependent induction of E-cadherin expression levels. Furthermore, the combinations of TSA (0.5 µM) with low doses of Sb (3.75-25 µM) in H1299 cells, significantly increased E-cadherin protein levels (24h), which remained sustained at later time points (48-72h) longer than with TSA alone treatments. Also, at these time points, Zeb1, a major transcriptional repressor of E-cadherin, was inversely down-modulated with the combination treatments. Substantial inhibition of invasion/migration of H1299 cells with similar treatment conditions further emphasized the biological significance of E-cadherin restoration. Unlike H1299 cells, treatment of H322 and H358 cells (with detectable E-cadherin level) with Sb (3.75-25 µM) alone was sufficient to consistently increase the basal levels of E-cadherin, with concomitant reduction of Zeb1 levels, which also led to inhibition of migratory potential of these cells. Overall these findings demonstrate that Sb alone or in combination with HDAC inhibitors upregulates E-cadherin expression levels in NSCLC cell lines, and this consequently leads to inhibition of invasion/migratory phenotype of these cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1608. doi:1538-7445.AM2012-1608
Abstract 161: The role of mTOR in the cisplatin resistant phenotype in ovarian cancer lineage
Authors: Ladislau Taciane , Silva Débora , Madeira Klesia Pirola , Daltoé Renata Dalmaschio , Paes Marcela Ferreira , Herlinger Alice Laschuck , Junior Paulo Cilas Morais Lyra , Silva Ian Victor , Rangel Leticia Batista Azevedo
Published: August 2012

Background Ovarian cancer (OVCA) is the second cause of gynecological-cancer deaths in Brazil, being frequently associated to chemotherapy resistance, a characteristic usually associated to PI3K/Akt/mTOR. We herein present data concerning the role of mTORC2 in cisplatin-resistant phenotype acquisition by OVCA cells. Methods Antineoplastic efficacy of cisplatin, doxorubicin, paclitaxel, and rapamycin was accessed, in different combinations, in the OVCA lineage OVCAR3 (cisplatin-resistant, advanced serous OVCA), through cellular metabolic viability (CMV) (MTT method). Cells were cultured in RPMI media supplemented with 10% (v/v) FBS and antibiotics until subconfluence. To characterize the role of mTORC1 or mTORC2 in OVCAR3 MCV, 1.5x105 cells/well were treated according to: EA1) Inhibition of mTORC1: Drugs at IC50 for 24h; EA2) Inhibition of mTORC1 and mTORC2: Rapamycin 100nM for 72h, followed by drugs at IC50 for 24h. Modulation of MTOR expression by PKA, PKC, and PI3K was investigated by real time RT-PCR. Statistical analysis was performed using PrismaGraphPad version 5.1. Findings OVCAR3 CMV was not significantly changed by cisplatin (IC50 0,08mM) nor paclitaxel (IC50 0,06nM) or rapamycin (IC50 0,02nM) (CMV 95%, 100%, 100%, respectively), but by doxorubicin (IC50 0,02nM) (CMV 60%), especially in combination with cisplatin (CMV 31%), following EA1. Considering the irreversible doxorubicin-induced cardiotoxicity, we pursued with EA2. Intriguingly, OVCAR3 cisplatin sensitivity was, at least partially, recovered (CMV 65%). No addictive effect was observed with cisplatin/doxorubicin following EA2 (CMV 60%), suggesting that OVCA-resistant patient might benefit from less toxic rapamycin-based chemotherapy, leaving doxorubicin for palliative final-staged disease management. Finally, neither PKA nor PI3K modulate MTOR expression; however, PKC suppresses its transcription by 4.42-fold. Interpretation Altogether, our data suggest that mTORC2, but not mTORC1, might influence cisplatin sensitivity in OVCA. Moreover, PKC inhibits the expression of MTORC in cisplatin-resistant OVCA. We propose that the inhibition of mTORC2 followed by cisplatin treatment might lead to a conjunction of autophagic cell death and apoptosis in OVCA. Of remarkable clinical interest, we point to the urge of better design clinical trials, in which not only novel drugs are tested, but also the chronological order of drugs administration to the patient is seen as crucial for treatment efficacy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 161. doi:1538-7445.AM2012-161
Abstract 1610: Curcumin inhibition of the functional interaction between integrin α6β4 and the epidermal growth factor receptor
Authors: Soung Young Hwa , Chung Jun
Published: August 2012

The functional interaction between integrin α6β4 and growth factor receptors has been implicated in key signaling pathways important for cancer cell function. However, few attempts have been made to selectively target this interaction for therapeutic intervention. Previous studies showed that curcumin, a yellow pigment isolated from tumeric, inhibits integrin α6β4 signaling important for breast carcinoma cell motility and invasion, but the mechanism is not currently known. To address this issue, we tested the hypothesis that curcumin inhibits the functional interaction between α6β4 and the epidermal growth factor receptor (EGFR). In this study, we found that curcumin disrupts functional and physical interactions between α6β4 and EGFR, and blocks α6β4/EGFR dependent functions of carcinoma cells expressing the signaling competent form of α6β4. We further demonstrated that curcumin inhibits EGF dependent mobilization of α6β4 from hemidesmosomes to the leading edges of migrating cells such as lammelipodia and filopodia, and thereby prevents α6β4 distribution to lipid rafts where functional interactions between α6β4 and EGFR occur. These data suggest a novel paradigm in which curcumin inhibits α6β4 signaling and functions by altering intracellular localization of α6β4, thus preventing its association with signaling receptors such as EGFR.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1610. doi:1538-7445.AM2012-1610
Abstract 1611: EGCG inhibits growth of human pancreatic tumors orthotopically implanted in BALB/c Nude mice through activation of FKHRL1/FOXO3a transcription factor.
Authors: Shankar Sharmila , Marsh Luke , Jackman Chris , Srivastava Rakesh K.
Published: August 2012

The forkhead transcription factors of the O class (FOXO) play a major role in cell proliferation, angiogenesis, metastasis and tumorigenesis. The objectives of this study were to examine whether FKHRL1/FOXO3a modulates antitumor activity of EGCG in pancreatic cancer model in vivo. PANC-1 cells were orthotopically implanted into BALB/c Nude mice and gavaged with EGCG after tumor formation. Cell proliferation and apoptosis were measured by Ki67 and TUNEL staining, respectively. FKHRL1 nuclear translocation, and DNA binding were measured by immunohistochemistry and gelshift assay, respectively. The expression of PI3K, AKT, ERK, and FOXO3a and its target genes were measured by the Western blot analysis. EGCG-treated mice showed significant inhibition in tumor growth which was associated with reduced phosphorylation of ERK, PI3K, AKT, FKHRL1/FOXO3a and expression of FOXO target genes. EGCG induced apoptosis by up-regulating Bim and activating caspase-3. EGCG inhibited markers of cell cycle (p27/KIP1), angiogenesis (CD31, VEGF, IL-6, IL-8 and HIF1α), and metastasis (MMP2 and MMP7). EGCG inhibited epithelial mesenchymal transition by upregulating the expression of E-cadherin and inhibiting the expression of N-cadherin, and Zeb1. These data suggest that EGCG inhibits pancreatic cancer orthotopic tumor growth, angiogenesis and metastasis which are associated with inhibition of PI3K/AKT and ERK pathways resulting in activation of FKHRL1/FOXO3a transcription factor.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1611. doi:1538-7445.AM2012-1611
Abstract 1615: Anthocyanin-rich black raspberry extract negatively regulates stem cell related molecules, EMT, and pluripotency of pancreatic cancer stem cells
Authors: Aravindan Natarajan , Aravindan Sheeja , Herman Terence S. , Natarajan Mohan
Published: August 2012

Ascertaining the potentials of diet-derived phenolics in eradicating cancer stem cells (CSCs), that proliferate and self-renew extensively leading to the initiation and progression of tumor, may escort significant clinical implications. Recently, we have shown that black raspberry extract (RSE) potentiates pancreatic cancer (PC) cell killing by targeting transcriptional machinery. Herein, we investigated ex vivo the effect of RSE on the regulation of EMT, pluripotency maintaining and other stem cell related molecules in PC-CSCs. CD133+CD44+CD24+ESA+ PC-CSCs isolated from human PC xenografts developed in athymic NCr-nu/nu nude mice with human MiaPaCa2, BXPC3, Panc-1 or Panc-3.27 cells were maintained in vitro. PC-CSCs exposed to RSE (2.0μg) for 3h were assessed for transcriptional regulation of 93 stem cell related molecules using QPCR profiling. Expression and cellular localization of epithelial-to-mesenchymal transition (EMT) markers and pluripotent maintaining factors including ABCG2, E-Cadherin, N-Cadherin, MYB, MYC, Nanog and SOX2 in MiaPaCa2, BXPC3 xenografts were assessed using immunohistochemistry (IHC). The results revealed that RSE significantly inhibited 83, 50 and 54 stem cell related molecules in PC-CSCs isolated from xenografts developed using MiaPaCa2, Panc-1 and Panc 3.27 respectively. Of these, 27 genes were commonly suppressed by RSE in all three PC-CSCs population. Further, IHC staining showed complete repression of EMT and pluripotent markers in both MiaPaCa2 and BXPC3 xenografts. Together, these data imply that RSE may exert selective inhibition of EMT and pancreatic CSCs’ self renewal capacity and, may thus serve as a potential “deliverable” to negate PC initiation and progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1615. doi:1538-7445.AM2012-1615
Abstract 1616: Preventive effects of EGCG on diethylnitrosamine-induced liver tumorigenesis in obese and diabetic C57BL/KsJ-db/db mice
Authors: Kochi Takahiro , Shimizu Masahito , Sakai Hiroyasu , Shirakami Yohei , Kubota Masaya , Tanaka Takuji , Moriwaki Hisataka
Published: August 2012

Background and aims: Obesity and related metabolic abnormalities, including insulin resistance and a state of chronic inflammation, increase the risk of hepatocellular carcinoma (HCC). Abnormal activation of the IGF/IGF-1R axis is also involved in obesity-related liver tumorigenesis. In the present study, we examined the effects of (-)-epigallocatechin gallate (EGCG), a major biologically active component of green tea, on the development of diethylnitrosamine (DEN)-induced liver tumorigenesis in C57BL/KsJ-db/db (db/db) obese mice. Methods: Male db/db mice were given tap water containing 40 ppm DEN for 2 weeks and then they received drinking water containing 0.1% EGCG for 34 weeks. Results: At sacrifice, drinking water with EGCG significantly inhibited the development of liver cell adenomas in comparison to the control EGCG-untreated group. EGCG inhibited the phosphorylation of the IGF-1R, ERK, Akt, GSK-3β, Stat3, and JNK proteins in the livers of experimental mice. The serum levels of insulin, IGF-1, IGF-2, free fatty acid, and TNF-α were all decreased by drinking EGCG. EGCG also decreased the expression of TNF-α, IL-6, IL-1α, and IL-18 mRNAs in the livers. In addition, EGCG improved liver steatosis and activated the AMPK protein in the liver. Conclusion: EGCG prevents obesity-related liver tumorigenesis by inhibiting the IGF/IGF-1R axis, improving hyperinsulinemia, and attenuating chronic inflammation. EGCG, therefore, may be useful in the chemoprevention of liver tumorigenesis in obese individuals.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1616. doi:1538-7445.AM2012-1616
Abstract 1617: Erianin induces apoptosis of human hepatocellular carcinoma HepG2 cells
Authors: Wang Jing , An Junxia , Zhu Qiyu , Luo Liping , Ma Yuling , Tang Yaxiong
Published: August 2012

Novel effective drugs are still urgently needed in the prevention and treatment of Hepatocellular carcinoma (HCC). Erianin, a natural product isolated from Dendrobium chrysotoxum Lindl., is often used as an anti-pyretic and an analgesic in traditional Chinese medicine. Herein, we have assesed the antitumor potential and molecular mechanisms of erianin on the Hepatocellular carcinoma HepG2 cancer cells in vitro. The results shows that erianin could significantly inhibit the cell proliferation of HepG2 cells in dose- and time- dependent manners that were associated with induced apoptosis and cell cycle G2-M arrest. The IC50 of erianin for 48 h was estimated to be 11.4 nmol/L. Mechanistically, erianin could induce the release of cytochrome c from mitochondria into the cytosol, and activate the cleavage of Caspase-9, -7, -3 and eventually the PARP in a dose-dependent manner, leading to marked apoptotic effect of HepG2 cells. The apoptotic action of erianian was associated with the increased expression of proapoptotic proteins: Bax, Bad, Bik and PUMA and decreased expression of Mcl-1 and Survivin. Taken together, these results suggest the potential usefulness of erianin for prevention and treatment of HCC. References 1. Gomaa AI, Khan SA, Toledano MB, Waked I, Taylor-Robinson SD. Hepatocellular carcinoma: epidemiology, risk factors and pathogenesis. World J Gastroenterol, 2008, 14 2. 2. Tang Y, Simoneau AR, Xie J, Shahandeh B, Zi X. Effects of the Kava Chalcone Flavokawain A Differ in Bladder Cancer Cells with Wild-type versus Mutant p53. Cancer Prevention Research 2008, 1(6):439-51. 3. Tang Y, Simoneau AR, Liao W, Guo Y, Hoang BH, Hope C, Liu F, Li S, Xie J, Holcombe RF, Jurnak FA, Mercola D, Zi X. WIF1, a Wnt pathway inhibitor, regulates SKP2 and c-myc expression leading to G1 arrest and growth inhibition of human invasive urinary bladder cancer cells. Molecular Cancer Therapeutics 2009, 8(2): 458-68.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1617. doi:1538-7445.AM2012-1617
Abstract 1622: Possible role of visfatin in hepatoma progression and the effects of branched-chain amino acids on visfatin-induced proliferation in human hepatoma cells
Authors: Shimizu Masahito , Ninomiya Soranobu , Moriwaki Hisataka
Published: August 2012

Obesity and related metabolic abnormalities, including adipocytokine dysbalance, are risk factors for hepatocellular carcinoma (HCC). Visfatin, an adipocytokine that is highly expressed in visceral fat, is suggested to play a role in the progression of human malignancies. Branched-chain amino acids (BCAA) reduces the incidence of HCC in obese patients with liver cirrhosis and prevents obesity-related liver carcinogenesis in mice. In this study, we investigated the possible role of visfatin on HCC progression and the effects of BCAA on visfatin-induced proliferation of HCC cells. In patients with HCC, serum visfatin levels were significantly correlated with stage progression and tumor enlargement. Visfatin preferentially stimulated the proliferation of HepG2, Hep3B, and HuH7 human HCC cells compared with Hc normal hepatocytes. Visfatin phosphorylated ERK, Akt, and GSK-3β proteins in HepG2 cells. LY294002 (a PI3K inhibitor), PD98059 (a MEK1 inhibitor), CHIR99021 (a GSK-3β inhibitor), and BCAA significantly inhibited visfatin-induced proliferation in HepG2 cells. BCAA also inhibited phosphorylation of GSK-3β, increased cellular levels of p21, caused cell cycle arrest in G0-G1, and induced apoptosis in HCC cells in the presence of visfatin. These findings suggest that visfatin plays a critical role in the proliferation of HCC cells and may be associated with the progression of this malignancy. In addition, BCAA might inhibit obesity-related liver carcinogenesis by targeting and, possibly, by overcoming the stimulatory effects of visfatin.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1622. doi:1538-7445.AM2012-1622
Abstract 1625: Curcumin induces expression of 15-hydroxyprostaglandin dehydrogenase in normal gastric mucosa RGM-1 cells: Possible involvement of AP-1
Authors: Jang Ji-Hye , Park Jong-Min , Woo Jeonghwa , Lee Young Wook , Surh Young-Joon , Na Hye-Kyung
Published: August 2012

Overproduction of prostaglandin E2 (PGE2) has been reported to be implicated in carcinogenesis. The intracellular level of PGE2 is regulated not only by its biosynthesis, but also by the degradation process. 15-Hydroxyprostaglandin dehydrogenase (15-PGDH) is the key enzyme that catalyzes the first step in the inactivation of PGE2. In the present study, we found that curcumin, a yellow coloring agent present in the rhizome of Curcuma longa Linn (Zingiberaceae), induced expression of 15-PGDH in normal rat gastric mucosa cells (RGM-1) in a concentration and time dependent manners. The mRNA level of 15-PGDH was also increased by curcumin treatment. By using deletion constructs of 15-PGDH promoter, we found that activator protein-1 (AP-1) is the most essential transcription factor responsible for curcumin-induced upregulation of 15-PGDH expression. Curcumin induced phosphorylation of ERK1/2 and JNK1/2, but did not affect activation of p38 MAP kinase. However, treatment with U0126 and SP600125, pharmacological inhibitors of ERK and JNK, respectively failed to suppress the induction of 15-PGDH expression in curcumin-treated RGM-1 cells. Curcumin enhanced the expression of c-Jun, c-Fos and CREB in the nuclear fraction of RGM-1 cells. In contrast, tetrahydrocurcumin which lacks the α,β-unsaturated carbonyl group failed to induce expression 15-PGDH, suggesting that the electrophilic α,β-unsaturated carbonyl group of curcumin plays a critical role in its induction of 15-PGDH expression in RGM-1 cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1625. doi:1538-7445.AM2012-1625
Abstract 1626: Honokiol inhibits IL-8 production and exerts anti-tumor effects in colon cancer cells: therapeutic and preventive implications
Authors: Arora Sumit , Srivastava Sanjeev K. , Bhardwaj Arun , Singh Ajay P. , Piazza Gary A. , Owen Laurie B. , Singh Seema
Published: August 2012

Interleukin-8 (IL-8), a member of CXC subfamily of chemokines, plays important roles in inflammation and cancer. The biological action of IL-8 is mediated through binding to its receptors, CXCR1 (IL-8RA) and CXCR2 (IL-8RB), which are members of the seven transmembrane G-protein-coupled receptor family. Overexpression of IL-8 has been detected in many human tumors, including colon cancer, and it is a major component of the inflammatory tumor microenvironment. Functional studies have shown that IL-8 acts as an autocrine/paracrine growth factor, and promotes growth, invasion, metastasis, angiogenesis and chemoresistance in colon cancer, implying that it could serve as a preventive and therapeutic target. In this study, we examined the effect of honokiol, a biologically active biphenolic compound isolated from the oriental medicinal plant Magnolia officinalis/grandiflora, on two colon cancer cells lines, SW620 and HCT116. Both the cell lines are highly tumorigenic and metastatic, and express high levels of IL-8. Our data demonstrated that honokiol inhibited the expression of IL-8 in both colon cancer cell lines in a dose-dependent manner. IL-8 downregulation by honokiol was also correlated with decreased activation of its transcriptional regulator NF-κB. Honokiol treatment enhanced cytoplasmic accumulation of NF-κB with a concomitant decrease in the nuclear fraction and reduced transcriptional activity of NF-κB-responsive promoter. This was associated with decreased phosphorylation of inhibitor of kappa B alpha (IαB-α) leading to its stabilization and enhanced cytoplasmic levels. In addition, honokiol exerted growth inhibitory effects by inducing apoptosis and G1 phase cell cycle arrest. Altogether, these findings suggest that honokiol could serve as a novel preventive and therapeutic agent in colon cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1626. doi:1538-7445.AM2012-1626
Abstract 1628: Tumor suppressor gene demethylation and reactivation in human colon cancer cells by black raspberry anthocyanins
Authors: Kuo Chieh-Ti , Seguin Claire , Stoner Kristen , Cho Seung-Ju , Weng Yui , Tichelaar Jay , Huang Yi-Wen , Huang Tim , Stoner Gary , Wang Li-Shu
Published: August 2012

Our laboratory has shown that the anthocyanins (ACs) in black raspberries (BRBs) are responsible for much of their chemopreventive effects in the rat esophagus. The present study was undertaken to determine the effects of BRB ACs on human colon cancer cells in vitro. Three days of AC treatment at 5 and 25 μg/ml medium significantly decreased cell proliferation and increased apoptosis in HCT116, Caco2, and SW480 human colon cancer cell lines. The ACs also reduced the activities and protein expression levels of DNA methyltransferases 1 and 3 (DNMT1, DNMT3) in all three cell lines. Promoter methylation of p16 (CDKN2A) and the Wnt pathway inhibitors, Sfrp2, Sfrp5 and Wif1, was decreased by AC treatment resulting in increased mRNA expression levels of all three Wnt inhibitors. ACs did not alter global methylation LINE-1. DNMT1 and DNMT3B knockout (KO) HCT116 cells were generated using siRNA to determine the role of these methyltransferases in AC-induced demethylation. In DNMT1 KO cells, the promoter methylation of Sfrp5 was reduced when compared with wild type HCT116 cells. AC treatment further reduced promoter methylation of Sfrp5 in DNMT1 KO cells suggesting that the ACs targeted protein(s) other than DNMT1 to regulate methylation. Promoter methylation of Sfrp5 was decreased to almost zero by treatment of DNMT3B KO cells with ACs. Interestingly, promoter methylation of p16 was reduced in both DNMT1 and DNMT3B KO cells, and AC treatment further reduced p16 methylation in both lines. In conclusion, these results suggest that ACs demethylated and reactivated tumor suppressor genes through regulation of DNMT1 and DNMT3B. This research was supported by NCI grant CA148818.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1628. doi:1538-7445.AM2012-1628
Abstract 1630: Vitamin E delta-tocotrienol prevents azoxymethane-induced colon carcinogenesis progression in Fisher-344 rats
Authors: Pimiento Jose M.
Published: August 2012

Background: Chemoprevention by bioactive food components has emerged as an alternative approach for the prevention of colorectal carcinogenesis. We have shown that natural vitamin E delta-tocotrienol is the most bioactive tocotrienol against pancreatic cancer. This study evaluated the efficacy of vitamin E delta-tocotrienol feeding in the prevention of azoxymethane-induced colorectal polyps and cancer formation in Fisher-344 rats. We also evaluated the antitumor activity of vitamin E delta-tocotrienol in colorectal cancer cell lines and in APCmin mouse model. Methods: The in vivo antitumor activity of delta-tocotrienol was evaluated in azoxymethane-treated Fisher-344 rats. Rats were administered azoxymethane (15 mg/kg, SC, 2 x in 2 weeks) then randomly selected into 3 groups: 1) No treatment, 2) Vehicle (ethanol extracted olive oil, 1 ml/kg, PO twice daily and 3) Delta-tocotrienol (200 mg/kg, PO) twice daily for 20 or 40 weeks. The animals were euthanized and the colons were examined for polyps and cancers. Colon tissues were fixed in buffered formalin, embedded, cut and stained with H & E and scored. The APCmin mice were treated with 1) vehicle (olive oil, 1 ml/kg, PO) twice daily for 2 weeks and 2) Delta-tocotrienol (200 mg/kg, PO) twice daily for 2 weeks. Mice euthanized and colon tissues isolated and evaluated for proliferation and apoptosis by immunohistochemistry staining. The in vitro anti-tumor activity of delta-tocotrienol was preformed in human colorectal cancer cell lines HCT-116, HT-29 and SW 480. Results: Delta-tocotrienol feeding to azoxymethane-treated rats significantly reduced (75%, p<0.002) the number of polyps formation compared to untreated or vehicle treated rats. Moreover, the number of colon cancer formation was reduced (70%, p<0.001) with delta-tocotrienol feeding compared to untreated or vehicle treated rats. In colonic tissues of APCmin mice, delta-tocotrienol feeding decreased proliferation (Ki-67), induction of p27, and induction of apoptosis (caspase-3) compared to vehicle treated mice. Delta-tocotrienol also inhibited cell proliferation and induced apoptosis in HCT-116, HT-29 and SW 480 cell lines, through induction of nuclear factor kappa-B (NF-kB) and degradation of beta-catenin. Conclusion: These data show the efficacy of natural vitamin E delta-tocotrienol against the early stages of colorectal carcinogenesis as well as anti-proliferative and apoptotic activity in colorectal cancer both in vitro and in vivo. Delta tocotrienol likely targets NF-kB and beta-catenin signaling pathways, suggesting its potential clinical usefulness for the prevention of human colorectal cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1630. doi:1538-7445.AM2012-1630
Abstract 1631: Protection of colon carcinogenesis by estrogen receptor-beta may involve regulation of angiogenesis and invasion specific signaling molecules
Authors: Saleiro Diana , Murillo Genoveva , Hawthorne Michael , Mehta Rajendra
Published: August 2012

Estrogen receptor-beta (ERα) has been suggested to exert anti-tumorigenic effects in the colon. However, its mechanism of action in colon cancer remains unclear. Previously, we demonstrated that azoxymethane (AOM) treated ERα knockout (≥ERKO) mice showed a significantly higher incidence of colonic precancerous lesions compared to AOM-treated WT mice. These results were associated with a decrease in apoptosis and loss of crypt organization in the colonic epithelium of αERKO mice. In the present study, we investigated whether ERα deficiency would also correlate with a higher incidence of colonic tumors. For this, αERKO and WT mice were injected subcutaneously with AOM (10mg/kg) once a week, for six weeks. Forty weeks after the beginning of the study, mice were sacrificed and colonic sections were collected for histopathology, RNA, and protein expression analysis. Evaluation of hematoxylin and eosin sections from each group showed that αERKO mice developed higher number of colonic adenomas (1.40 ± 0.40) than WT mice (0.33 ± 0.21) (p < 0.05). Furthermore, Mouse Cancer PathwayFinder Superarray revealed a greater than two-fold increase of angiogenesis and invasion specific signaling molecules in ERα-deficient tumors compared to WT ones. These findings highlight the importance of ERα against colon carcinogenesis progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1631. doi:1538-7445.AM2012-1631
Abstract 1634: Metabolomic profiling for early detection of colorectal neoplasia
Authors: Montrose David C. , Kopelovich Levy , Zhou Xi Kathy , Yantiss Rhonda , Subbaramaiah Kotha , Dannenberg Andrew
Published: August 2012

Introduction: Colorectal cancer (CRC) is the 3rd leading cause of cancer-related deaths in the world. Colonoscopy is widely used for early detection and removal of colorectal neoplasia to prevent CRC. However, it is both invasive and costly underscoring the need for new strategies to identify subjects for whom colonoscopy is most appropriate. Metabolomics is a high throughput method of detecting small molecules which provides a platform for identifying novel biomarkers of colorectal neoplasia. In this study, we investigated whether metabolic changes could be identified in the feces and plasma in a model of experimental CRC. Methods: Five week old male A/J mice were administered six weekly intraperitoneal injections of either azoxymethane (AOM) (10mg/kg) (n=40) or 0.9% saline (n=35). Following injections, feces, plasma and tumor tissue or normal colonic mucosa were collected and stored at −80oC for metabolomic analysis. Five mice from the AOM injected group were sacrificed at each of three time points (three, five and seven weeks after the last injection) to assess tumor burden. UPLC/MS/MS and GC/MS were used to quantify metabolite levels in feces, plasma and tissue. Results: Histological analysis of tumor burden in the colon showed a progressive increase as a function of time after AOM administration. Metabolomic analysis revealed a large number of significantly changed metabolite levels in both the feces and plasma during colon carcinogenesis. These included amino acids and peptides in feces as well as bile acids in the plasma. A select number of these metabolites were found to progressively change as a function of time in both feces and plasma in relation to increased tumor burden. Significantly, certain metabolites changed in the same direction in feces and tumor tissue, plasma and tumor tissue as well as across all three matrices, suggesting that these may be tumor-derived. For example, samples from AOM injected mice showed increased levels of sarcosine and 2-hydroxyglutarate, metabolites previously implicated in prostate cancer and gliomas/AML, respectively. Conclusions: This study demonstrates the potential utility of metabolomic analyses for the early detection of colorectal neoplasia. Additionally, the finding of increased levels of two onco-metabolites (sarcosine, 2-hydroxyglutarate) in colorectal neoplasia suggests their potential involvement in colon carcinogenesis. Future studies in humans will be required to determine the significance of these findings.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1634. doi:1538-7445.AM2012-1634
Abstract 1635: Effect of dietary fish oil on rat colonic prostaglandin (PG) E2 metabolism
Authors: Jiang Yan , Ren Jianwei , Waters Ian , Smith William L. , Brenner Dean E.
Published: August 2012

PGE2, an eicosanoid generated from arachidonic acid (AA) by the cyclooxygenase function of prostaglandin H synthases (PGHS)-1 and 2, has been linked to the risk of many cancers including colorectal carcinogenesis. Targeting colonic PGE2 homeostasis by utilizing nutritional products such as fish oil may reduce endogenous PGE2 that, in turn, may decrease subsequent inflammatory events that lead to carcinogenesis. Rats were fed high fat fish oil diets contained different ratios of eicosapentaenoic acid (EPA) and n-6 fatty acid. The colon was horizontally divided into three equal length transections, first (proximal end), second (transverse) and third (distal end). Enzymes involved in PGE2 metabolism (15-hydroxyprostaglandin dehydrogenase (15-PGDH) and PGE synthase (mPGES)) were measured using quantitative PCR and semi-quantitative Western Blotting. GC-MS analysis was performed to detect fatty acid levels in serum and colon. LC-MS/MS analysis was used to examine eicosanoid levels. Our results showed that the colonic epithelial mucosa contained less PGE2 per mg of protein than did the whole colon. Colonic PGE2 and several eicosanoids including 13-Hydroxyoctadecadienoic acid(13HODE), 5-Hydroxyeico-satetraenoic acid (5 HETE), 15-Hydroxyeicosatetraenoic acid (15 HETE) and 12-Hydroxyeicosatetraenoic acid (12 HETE) were distributed differentially in different part of the colon. Dietary fish oil intake increased tissue levels of EPA in the colon. PGHS-2 gene was affected the most by dietary fish oil among all the genes tested in normal colon. Fish oil dose-dependently decreased PGHS-2 mRNA expression in all three colon sections. mRNA expression of 15-PGDH was higher in the third colonic section than the first two sections; however it was not altered by dietary fish oil. In conclusion, different parts of the colon have different eicosanoid profiles. The decreases in PGE2 in normal colon observed with fish oil feeding do not appear to be related to expression of PGHS-1, mPGES and 15-PGDH but are most closely correlated with PGHS-2 despite that PGHS-2 levels are already low in the normal colon. These data support the concept of anatomic variability in colonic carcinogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1635. doi:1538-7445.AM2012-1635
Abstract 164: High throughput homogenous bioluminescent assays for monitoring the concentrations of AMP, ADP and ATP
Authors: Goueli Said A. , Hsiao Kevin , Zegzouti Hicham
Published: August 2012

Adenine nucleotides are major determinants of the energy status of the cell and thus any modulation of their cellular concentration has significant consequences to cellular metabolism, cellular growth and cell death. ATP generating enzymes are usually involved in anabolic processes while ATP consuming enzymes are involved in catabolite processes. We have developed biochemical assays that monitor the concentrations of ATP, ADP and AMP in a biochemical reaction. For instance ATP depletion dependent assays and ADP generating assays monitor the activity of kinases and ATPases. These universal assays can measure the activity of various enzymes with no modification of the native substrate and the ability to use diverse substrates such as proteins, peptides, lipids, sugars, etc. The AMP generating reactions such as ubiquitin ligases, aa aminoacyl t-RNA synthetases, DNA ligases, cAMP-dependent phosphodiesterases, etc. can be also monitored with high sensitivity and reproducibility. We will show data using these various technologies in monitoring the various adenine nucleotide concentrations in biochemical reactions.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 164. doi:1538-7445.AM2012-164