bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 845: Heparin-like polysaccharides reduce osteolytic bone destruction and tumor growth in a mouse model of breast cancer bone metastasis
Authors: Pollari Sirkku , Käkönen Rami , Mohammad Khalid S. , Rissanen Jukka P. , Halleen Jussi , Wärri Anni , Nissinen Liisa , Pihlavisto Marjo , Marjamäki Anne , Perälä Merja , Guise Theresa , Kallioniemi Olli , Käkönen Sanna-Maria
Published: June 2012

Transforming growth factor β (TGF-β) is a key regulator of several steps in cancer metastasis, including the establishment of bone metastatic lesions. TGF-β is released from bone during osteoclastic bone resorption and it stimulates breast cancer cells to produce osteolytic factors such as interleukin 11 (IL-11). We conducted a cell-based siRNA screen and identified heparan sulfate 6-O-sulfotransferase 2 (HS6ST2) as a critical gene for TGF-β-induced IL-11 production in highly bone metastatic MDA-MB-231(SA) breast cancer cells. HS6ST2 attaches sulfate groups to glucosamine residues in heparin sulfate which is a member of the glycosaminoglycan family of carbohydrates. Our subsequent studies with highly sulfated heparin-like glycosaminoglycans (HLGAGs) with low anti-coagulant activity indicated that a high-molecular-weight E. coli K5-derived heparin-like polysaccharide (K5-NSOS) inhibited TGF-β-induced IL-11 production in MDA-MB-231(SA) cells. We then evaluated the therapeutic potential of K5-NSOS and a low-molecular-weight synthetic heparin (fragmin) in a mouse model of breast cancer bone metastasis. MDA-MB-231(SA) cells were inoculated into the left cardiac ventricle of athymic nude mice which were then administered with K5-NSOS, fragmin, or vehicle once daily for 4 weeks. Both HLGAGs increased body weight, decreased osteolytic lesion area, and reduced tumor burden in bone. Our in vitro studies showed that both K5-NSOS and fragmin inhibited adhesion of breast cancer cells to ICAM-1, and K5-NSOS also inhibited adhesion to E- and P-selectin. Furthermore, K5-NSOS inhibited bone resorption activity of human osteoclasts in vitro. Our data support and further clarify the critical role of heparan sulfate glycosaminoglycans in breast cancer metastasis and indicate that K5-NSOS is a potential antimetastatic and antiresorptive agent with low anticoagulant activity that could be further optimized as an anti-tumor agent.

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 845. doi:10.1158/1538-7445.AM2011-845
Abstract 847: Resolvin D1 stimulates efferocytosis through p50/p50-mediated suppression of tumor necrosis factor-α
Authors: Lee Ha-Na , Kundu Joydeb Kumar , Shin Jun-Wan , Cha Young-Nam , Surh Young-Joon
Published: June 2012

Phagocytosis of apoptotic neutrophils by macrophages, called efferocytosis, is critical to resolution of inflammation as this process prevents the exposure of surrounding tissues at the inflammatory site to the toxic contents of lytic cells. Docosahexaenoic acid-derived resolvin D1 (RvD1), endogenously generated during resolution of inflammation, is known to stimulate efferocytosis, but little is known about the mechanism of its action. In the present study, we found that lipopolysaccharide (LPS; 200 μg/ml) suppressed efferocytosis by murine macrophage-like RAW264.7 cells, and RvD1 (50 nM) restored the phagocytic ability of these cells by down-regulating TNF-α expression. The inhibitory effect of RvD1 on LPS-induced TNF-α expression was associated with enhanced nuclear localization of p50/p50 homodimer and concomitant reduction in the nuclear levels of p65/p50 heterodimer. RvD1 triggered extracellular signal-regulated kinase (ERK)- and Akt-mediated nuclear factor κB1 (NF-κB1) p105 degradation and subsequently translocation of p50/p50 homodimer to nucleus in RAW264.7 cells. In contrast, LPS-induced nuclear translocation and DNA binding of p65/p50 heterodimer were attenuated by RvD1 treatment through inhibition of IκBα degradation. siRNA knockdown of NF-κB p50 abolished RvD1-mediated suppression of TNF-α expression and resulted in impaired efferocytosis, suggesting that the replacement of p65/p50 with p50/p50 homodimer is an essential event for RvD1-mediated stimulation of efferocytosis. In a murine peritonitis model, intraperitoneal administration of RvD1 (300 ng) abrogated zymosan A (30 mg/kg)-induced TNF-α production, thereby reactivating efferocytosis. In addition, RvD1 significantly reduced polymorphonuclear leukocyte infiltration while it increased monocyte infiltration. Taken together, these findings indicate that RvD1 expedites resolution of inflammation via p50/p50-mediated repression of TNF-α production.

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 847. doi:10.1158/1538-7445.AM2011-847
Abstract 849: Autophagic cell death response to benzyl isothiocyanate exposure in human breast cancer cells is mediated by FoxO1
Authors: Xiao Dong , Bommareddy Ajay , Singh Shivendra V.
Published: June 2012

Benzyl isothiocyanate (BITC), a constituent of edible cruciferous vegetables (e.g., gardencress), is empowered to prevent chemically-induced cancers as well as oncogene-driven spontaneous mammary cancer development in rodent models. Furthermore, BITC treatment effectively inhibits growth of cultured as well as xenografted human breast cancer cells. However, the mechanisms underlying cancer chemopreventive responses to BITC are not fully understood. We now demonstrate, for the first time, that BITC causes FoxO1-mediated autophagic cell death in human breast cancer cells. Exposure of MDA-MB-231 (an estrogen-independent cell line with mutant p53) and MCF-7 (an estrogen-receptor positive cell line with wild-type p53) human breast cancer cells to BITC resulted in autophagy characterized by appearance of double-membrane structures judged by transmission electron microscopy, formation of acidic vesicular organelles evidenced by microscopy following staining with lysosomotropic agent acridine orange, cleavage of LC3 evidenced by immunoblotting, and punctuate localization of LC3. Interestingly, a spontaneously immortalized and non-tumorigenic human mammary epithelial cell line (MCF-10A) was resistant to autophagy induction by BITC. BITC-mediated growth inhibition and apoptotic cell death resulting from 6 hour treatment was significantly attenuated in the presence of autophagy inhibitor 3-methyladenineand (3-MA; a phosphatidylinositol 3-phosphate kinase inhibitor) and bafilomycin A1 (an inhibitor of vacuolar type H+-ATPase). On the other hand, growth inhibition and apoptotic DNA fragmentation resulting from 24 hour exposure to BITC was not prevented by either 3-MA or bafilomycin A. Furthermore, inhibition of MDA-MB-231 xenograft growth in female athymic mice by BITC administration (2.5 and 7.5 µmol BITC/mouse by i.p. injection) correlated with cleavage of LC3. BITC-induced autophagy was accompanied by induction of FoxO1. Moreover, RNA interference of FoxO1 conferred significant protection against BITC-mediated growth inhibition and autophagy. In conclusion, these results indicate that autophagy is an early event in growth inhibition by BITC against human breast cancer cells, which culminates into apoptotic cell death following longer exposures (e.g., 24 hours). This investigation was supported by the USPHS grant RO1 CA129347-04, awarded by the National Cancer Institute.

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 849. doi:10.1158/1538-7445.AM2011-849
Abstract 852: Apoptosis induction by ayurvedic medicine constituent withaferin A in human breast cancer cells is mediated by reactive oxygen species-dependent activation of Bak
Authors: Hahm Eun-Ryeong , Moura Michelle B. , Kelley Eric E. , van Houten Bennett , Singh Shivendra V.
Published: June 2012

Withaferin A (WA) is a promising cancer chemopreventive constituent of Ayurvedic medicine plant Withania somnifera that has been used safely for thousands of years in India for treatment of different ailments. We have shown previously that WA treatment suppresses viability of cultured as well as xenografted human breast cancer cells by causing apoptosis but the mechanism of cell death is not fully understood. Here, we demonstrate that the WA-induced apoptosis in human breast cancer cells is mediated by reactive oxygen species (ROS)-dependent activation of Bak. WA treatment caused ROS production in MDA-MB-231 (an estrogen-independent cell line with mutant p53) and MCF-7 cells (an estrogen-responsive cell line with wild-type p53) in a concentration- and time-dependent manner as judged by flow cytometry and fluorescence microscopy using a chemical probe (MitoSOX Red) and EPR spectroscopy using a cell permeable spin probe (1-hydroxy-3-methoxy-carbonyl-2,2,5,5-tetramethylpyrrolidine). WA-mediated ROS production, as well as, apoptosis [characterized by release of histone-associated DNA fragments into the cytosol, and cleavage of poly-(ADP-ribose) polymerase or procaspase-3], was significantly attenuated by ectopic expression of Cu,Zn-superoxide dismutase (SOD) or Mn-SOD. Real-time measurements of oxygen consumption rate and extracellular acidification rate using a Seahorse Bioscience XF24 Extracellular Flux Analyzer revealed that the ROS production resulting from WA exposure was accompanied by inhibition of basal and reserve oxidative phosphorylation. Mitochondrial DNA-deficient Rho-0 variants of MDA-MB-231 and MCF-7 cells were significantly more resistant to WA-induced ROS production and apoptosis compared with respective wild-type cells. WA treatment resulted in activation of Bax and Bak, but only Bak activation was attenuated by Cu,Zn-SOD overexpression. Furthermore, RNA interference or genetic suppression of Bax and Bak expression conferred significant protection against WA-induced apoptosis. In conclusion, the present study provides novel insights into the molecular circuitry of WA-induced apoptosis involving ROS-dependent activation of Bak. This investigation was supported by the USPHS grant CA142604-01, awarded by the National Cancer Institute.

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 852. doi:10.1158/1538-7445.AM2011-852
Abstract 858: Transplacental cancer prevention by indole-3-carbinol via estrogen receptor beta
Authors: Benninghoff Abby D. , Fish Trevor , Packard Brittany C. , Castro David J. , Shorey Lyndsey E. , Williams David E.
Published: June 2012

Indole-3-carbinol (I3C), a key active component of cruciferous vegetables, was recently shown to be an effective anticancer agent when administered transplacentally to mice via the maternal diet. The chemopreventive properties of I3C can involve multiple mechanisms of action, including interaction with the aryl hydrocarbon receptor (AhR) and the estrogen receptor (ER). In this prior transplacental cancer study, the chemopreventive property of I3C was not dependent on the AhR. In the present study, the therapeutic efficacy of I3C in prevention of cancer in offspring exposed in utero to the environmental carcinogen dibenzo[a,l]pyrene (DBP) was evaluated using an ER beta knockout mouse model. B6129SF1/J-Esr2+/- dams and sires were crossed to generate offspring that were either wild-type, heterozygous or null for ER beta. Dams were initiated with 15 mg/kg DBP or sham (corn oil) on gestation day 17. Three experimental diets were evaluated as follows: group 1, dams and offspring were fed control diet throughout the study; group 2, dams were fed 2000 ppm I3C from gestation day 9 through lactation (I3C-GL); and group 3, offspring were fed 2000 ppm I3C from weaning until 6 months of age (I3C-PW). As previously observed, offspring in the DBP-initiated control group developed T-cell lymphoblastic lymphoma by 20 weeks of age, whereas mice in the I3C-GL group were less likely to succumb to the disease (p<0.0001). Although I3C did not reduce incidence of lung cancer in the surviving offspring, lung tumor multiplicity in mice exposed to I3C during gestation and lactation (I3C-GL) was significantly reduced compared to control (p<0.05). I3C administered directly to the offspring (I3C-PW) did not provide protection against DBP-dependent lymphoma or reduce lung tumor multiplicity. This observation points to the critical gestation/lactation window of exposure for chemoprevention by this compound. A significant effect of ER beta genotype was observed in offspring exposed to I3C during gestation and lactation, only. Lymphoma-related mortality was very low in offspring expressing one or both copies of ER beta (+/-, 89% survival; +/+, 96% survival), whereas mortality in offspring lacking ER beta was significantly higher (−/-, 58% survival; p=0.0001.) Interestingly, in this diet group, lung tumor multiplicity in ER beta null offspring was significantly lower than wild-type or heterozygous mice. Collectively, these findings suggest that I3C acts via ER beta to exert its anticancer effects when administered transplacentally to offspring via the maternal diet. Supported by grants F32ES014777, P01CA090890 and the Linus Pauling Institute.

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 858. doi:10.1158/1538-7445.AM2011-858
Abstract 859: EGCG inhibits pancreatic cancer growth and stem cell characteristics in xenografts and KrasG12D transgenic mice models
Authors: Tang Su-Ni , Marsh Luke , Shankar Sharmila , Srivastava Rakesh K.
Published: June 2012

FoxO (forkhead box O) transcription factors are crucial regulators of cell fate. This function of FoxO proteins relies on their ability to control diverse functions such as proliferation, differentiation, DNA repair and apoptosis. Constitutively active AKT and ERK in cancer cells have been shown to phosphorylate FoxO transcription factors (FKHR, FKHRL1 and AFX), which bind to protein 14-3-3 and sequester in the cytoplasm. In the absence of survival signals, FoxO proteins dephosphorylate, translocate to the nucleus and upregulate a series of target genes, thereby promoting cell cycle arrest and apoptosis. EGCG, a component of green tea, exerts antiproliferative and proapoptotic actions on a number of different cancer cell lines through diverse mechanisms. However, the mechanisms by which EGCG inhibits cell proliferation and induces apoptosis are poorly understood. EGCG inhibited viability and induced apoptosis in human pancreatic cancer cell lines. EGCG induces PTEN expression and inhibits Akt phosphorylation in pancreatic cancer Hs766T, AsPC-1, MIA PaCa-2 and PANC-1 cells. Treatment of PANC-1 cells with EGCG caused a decrease in ERK phosphorylation, and an increase in JNK phosphorylation. Overexpression of FOXO1, FOXO3a, and FOXO4 inhibited cell viability in PANC-1 cells. The inhibitory effects of EGCG on cell viability were further enhanced when cells were transfected with FOXO1, FOXO3a, and FOXO4. EGCG enhanced FOXO-DNA binding and transcriptional activities. Interestingly, EGCG inhibited pancreatic cancer growth and/or development in xenograft, orthotopic and KrasG12D transgenic mice models. EGCG also inhibited pancreatic cancer stem cell characteristics. In conclusion, our data demonstrate that EGCG can inhibit pancreatic cancer growth and/or development through multiple mechanisms and thus can be used for the management of pancreatic 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 859. doi:10.1158/1538-7445.AM2011-859
Abstract 861: Nrf2-mediated induction of heme oxygenase-1 expression by cyclopentenone prostaglandin analogues in human breast epithelial cells: Structure-activity relationships
Authors: Park Jong-Min , Kim Nam-Jung , Na Hye-Kyung , Suh Young-Ger , Surh Young-Joon
Published: June 2012

15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2), an endogenous ligand of peroxisome proliferator-activated receptor γ, has been known to induce heme oxygenase-1 (HO-1) in certain cell lines. The mechanism by which 15d-PGJ2 upregulates HO-1 expression is considered to involve covalent modifications of critical cysteine residues of Keap1, a cytoplasmic repressor of Nrf2. This facilitates dissociation of Nrf2 from Keap1 for nuclear translocation and binding to the antioxidant response element. In the present work, we synthesized a series of 15d-PGJ2 analogues: i) Halogenated 15d-PGJ2 derivatives by introducing an electron withdrawing group, i.e., halogen into the electrophilic carbon; ii) Olefin modified 15d-PGJ2 analogues by saturating an electrophilic α,β-unsaturated carbonyl moiety in the cyclopentenone ring; iii) Combined halogenated and olefin modified 15d-PGJ2 analogues with more potent electrophilic nature to form stable Keap1 adducts. Twelve 15d-PGJ2 analogues were synthesized that retain the essential structural features of 15d-PGJ2 with different capabilities to induce Nrf2 activation. When treated to the human breast epithelial cell line (MCF10A), halogenated 15d-PGJ2 analogues were found to have high potency and efficacy for inducing HO-1 expression as well as Nrf2 activation (-Cl > -Br > -F = -I). 14,15-Dihydro-PGJ2 also retains capability to induce HO-1 expression and Nrf2 activation. However, abilities of both 9,10-dihydro-15d-PGJ2 and 12,13-14,15-tetrahydro-PGJ2 to induce HO-1 expression and Nrf2 activation were abolished due to lack of the electrophilic α,β-unsaturated carbonyl moiety. Chlorinated 14,15-dihydro-PGJ2 has the highest potency and efficacy for HO-1 induction via Nrf2 activation. We further showed that biotinylated 15d-PGJ2 directly bound to Keap1, which was confirmed by avidin pull-down. Biotinylated chloro 14,15-dihydro-PGJ2 interacted with Keap1 to a greater extent than did 15d-PGJ2. In contrast to 15d-PGJ2, 9,10-dihydro-15d-PGJ2 failed to modify Keap1. Taken together, these results suggest that 15d-PGJ2 containing an electrophilic cyclopentenone moiety can directly modify Keap1, presumably at its critical cysteine residue. As halogenated 15d-PGJ2 analogues and 14,15-dihydro-PGJ2 can stably interact with Keap1, they can be utilized as lead compounds for the development of anti-inflammatory and chemopreventive agents.

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 861. doi:10.1158/1538-7445.AM2011-861
Abstract 864: Benzyl isothiocyanate, a promising cancer chemopreventive constituent of cruciferous vegetables, inhibits epithelial to mesenchymal transition in human breast cancer cells in vitro and in vivo
Authors: Sehrawat Anuradha , Singh Shivendra V.
Published: June 2012

Benzyl isothiocyanate (BITC), a constituent of cruciferous vegetables (e.g., garden cress), inhibits chemically-induced cancer in experimental rodents. We showed previously that BITC treatment inhibited growth of cultured (MDA-MB-231 and MCF-7) and xenografted (MDA-MB-231) human breast cancer cells by causing reactive oxygen species-dependent apoptosis, and suppressed mammary cancer development in a transgenic mouse model (MMTV-neu). We now demonstrate, for the first time, that BITC is a potent inhibitor of epithelial to mesenchymal transition (EMT) in cultured cells and tumor xenografts in vivo. Exposure of estrogen receptor negative (MDA-MB-231) and estrogen receptor positive human breast cancer cells (MCF-7) and a highly invasive pancreatic cancer cell line (PL-45) to pharmacologic concentrations of BITC (1 or 2.5 µmol/L) resulted in up-regulation of epithelial markers (e.g., E-cadherin and occludin) with a concomitant decline in protein levels of mesenchymal markers vimentin, fibronectin, snail, and/or c-Met. BITC-mediated induction of E-cadherin protein correlated with its transcriptional up-regulation. Experimental EMT induced by exposure to TGFβ and TNFα in a spontaneously immortalized and non-tumorigenic human mammary epithelial cell line (MCF-10A) was also largely reversible in the presence of BITC. Consistent with these results, the BITC treatment inhibited TGFβ/TNFα -induced migration by MCF-10A cells, which was partially but significantly attenuated by RNA interference of E-cadherin. Moreover, inhibition of MDA-MB-231 xenograft growth in vivo in female athymic mice by BITC administration correlated with a visible increase in protein level of E-cadherin and suppression of vimentin protein expression. In conclusion, the present study reports a novel anticancer effect of BITC involving inhibition of EMT, a process triggered during progression of carcinoma to invasive state. This investigation was supported by the USPHS grant RO1 CA129347-04, awarded by the National Cancer Institute.

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 864. doi:10.1158/1538-7445.AM2011-864
Abstract 868: Replication of melanoma GWAS hits and exploration of pleiotropic effects of cancer GWAS hits with melanoma risk in the PAGE study
Authors: Kocarnik Jonathan D. , Carty Cara , Lin Yi , Fesinmeyer Megan D. , Haessler Jeff , Kooperberg Charles , Peters Ulrike ,   PAGE Consortium
Published: June 2012

Introduction: As the most serious form of skin cancer, melanoma is a considerable public health burden. Genome wide association studies (GWAS) have successfully identified several loci important to melanoma susceptibility. Some of these loci have been associated with other cancers as well, similar to the pleiotropy previously demonstrated in the 8q24 and TERT regions. Such pleiotropy can highlight important regions and may help inform variant functionality. However, the potential pleiotropic effects of gene variants identified for other cancers have not been fully explored for melanoma. This study evaluates whether GWAS hits for melanoma, as well as hits for non-melanoma cancers, are associated with melanoma risk.

Methods: We included 918 white melanoma cases and 4495 white controls in the Women's Health Initiative, which were genotyped as part of the Population Architecture using Genomics and Epidemiology (PAGE) study. We evaluated 8 single nucleotide polymorphisms (SNPs) previously shown to be associated with melanoma in GWAS as well as 175 SNPs previously shown to be associated with other cancers. These findings were mostly based on GWAS in Caucasian populations. We used logistic regression to evaluate the association between each SNP and melanoma risk, using an age-adjusted additive genetic model.

Results: Of the 8 melanoma SNPs evaluated, 7 were statistically significantly associated with melanoma risk (p<0.05). These SNPs were rs1393350 (p=0.001), rs16891982 (p=3.34e-05), rs258322 (p=1.53e-9), rs4785763 (p=3.29e-4), rs7023329 (p=2.20e-5), rs910873 (p=2.38e-4), and rs4636294 (p=5.82e-5). For each of these significant SNPs, the association was in the same direction of risk as previously reported. The SNP that did not replicate was rs2284063 (p=0.38). Our analysis for pleotropic effects of other cancer GWAS hits did not yield any significant associations after adjustment for multiple comparisons (p=2.87e-4). The most significant SNP was rs710521 (p=0.006), previously associated with urinary bladder cancer.

Conclusions: This preliminary analysis demonstrates that nearly all previously discovered melanoma SNPs replicated. Our analysis did not discover any non-melanoma cancer SNPs that are also associated with melanoma. The next step in this analysis will be to incorporate data from the other three PAGE studies: the Multiethnic Cohort (MEC), Epidemiologic Architecture of Genes Linked to Environment (EAGLE), and the CALiCo Consortium (see pagestudy.org). This will substantially improve the power of our pleiotropy analyses.

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 868. doi:10.1158/1538-7445.AM2011-868
Abstract 879: A functional promoter polymorphism (−1362G>T) of IL-6 gene is associated with the risk of squamous cell carcinoma of head and neck
Authors: Huang Yu-Jing , Niu Jiangong , Wang Li-E , Liu Zhensheng , Sturgis Erich M. , Wei Qingyi
Published: June 2012

Interleukin-6, an immunoregulatory cytokine, plays a crucial role in the pathogenesis of a wide variety of human cancers, and the IL-6 levels have been shown to be associated with tumor progression in human squamous cell carcinoma of the head and neck (SCCHN). Because the presence of polymorphisms in the non-coding gene regulatory region may affect transcriptional regulation of IL-6, we hypothesized that such genetic variants of IL-6 might contribute to susceptibility to SCCHN. To assess the association between IL-6 polymorphisms and SCCHN risk, two independent IL-6 promoter SNPs, -1362 G>T (rs2069827) and -597 G>A (rs1800797), the latter being in nearly complete linkage disequilibrium with -173 C>G (rs1800795), were genotyped in 1,092 non-Hispanic White SCCHN patients and 1,126 age-and sex-matched cancer-free controls. After adjustment for age, sex, and smoking and drinking status, a significantly higher risk was observed for the -1362GT+TT genotypes (adjusted OR = 1.28, 95% CI = 1.01-1.62), compared with those carrying the -1362GG homozygotes, but not for the -597G>A SNP. Additional functional experiment demonstrated that the IL-6 SNP -1362 G-to-T allelic change was associated with an increased promoter activity in human head and neck cell lines, supporting the hypothesis that genetic polymorphism influencing IL-6 transcription may play a role in human SCCHN carcinogenesis. We conclude that the IL-6 promoter -1362 G>T (rs2069827) polymorphism is functional, modulating susceptibility to SCCHN among non-Hispanic Whites. Larger studies are needed to validate our findings. (Supported by NIH grants R01CA131274, R01ES011740 and P30 CA016672)

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 879. doi:10.1158/1538-7445.AM2011-879
Abstract 880: Polymorphisms of PLCE1 and KIF1B and risk of squamous cell carcinoma of the head and neck
Authors: Ma Hongxia , Wang Li-E , Liu Zhensheng , Sturgis Erich M , Wei Qingyi
Published: June 2012

Recent genome-wide association studies (GWAS) of gastric cancer, esophageal squamous cell carcinoma and hepatocellular carcinoma have identified PLCE1 and KIF1B as novel cancer susceptibility genes. In this study, we investigated associations between risk of squamous cell carcinoma of the head and neck (SCCHN) and potentially functional variants in PLCE1 and KIF1B. Three single nucleotide polymorphisms (SNPs, rs2274223G>A, rs3203713G>A and rs11599672T>G) of PLCE1 and four SNPs (rs17401966A>G, rs1002076G>A, rs17401588A>G and rs1536262C>T) of KIF1B were genotyped by Taqman in 1,098 patients with SCCHN and 1,090 cancer-free controls, who were non-Hispanic whites matched by age (± 5 years) and sex. Although none of three SNPs of PLCE1 was alone significantly associated with overall risk of SCCHN, the combined genotypes [the number (0-6) of putative risk alleles (rs2274223G, rs3203713G and rs11599672G)] had a significant locus-dose effect on risk of SCCHN (Ptrend=0.046), particularly of non-oropharyngeal cancers (P trend=0.017), suggesting a joint effect of these SNPs on susceptibility to SCCHN. Further, the subgroup analysis showed that variant genotypes of rs2274223 and rs11599672 were independently associated with risk of non-oropharyngeal cancers, respectively. Of four SNPs of KIF1B, we found that rs1536262 variant had a significant association with the increased risk of SCCHN (additive model: adjusted OR = 1.15, 95% CI = 1.02-1.30) and the association was more evident in older subjects, females, former smokers, subjects with tumors of hypopharynx/ larynx, and subjects with poor progression tumor. Rs1536262 is located in 3’UTR region of KIF1B, a potentially functional SNP that may affect the binding of miRNA. Continuous efforts are underway in our laboratory to investigate potentially functional significance of rs1536262 in the development of SCCHN. In conclusion, our findings implicated a possible role of PLCE1 and KIF1B variants in the susceptibility to SCCHN, but larger studies are needed to validate our findings.

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 880. doi:10.1158/1538-7445.AM2011-880
Abstract 888: Genetic variability in lipid metabolism and risk of lung cancer
Authors: Zhang Jianjun , Tanaka Hideo , Ito Hidemi , Boffetta Paolo , Matsuo Keitaro
Published: June 2012

Lung cancer is the leading cause of cancer death in many countries across the world. A growing body of evidence indicates that fat (especially saturated fat) is involved in lung carcinogenesis. Lung cancer incidence is higher among countries with high intake of fat. Some, although not all, epidemiologic studies have shown that fat intake was associated with an increased risk of lung cancer. Animal studies demonstrated that fat interacted with tobacco carcinogens to influence occurrence of lung tumors. Collectively, it is possible that genetic variability in lipid metabolism may modulate the risk of lung cancer. We sought to investigate this hypothesis in a hospital-based case-control study conducted from 2000 to 2005 in Nagoya, Japan. Cases (n=230), ages 20-79, were patients pathologically diagnosed with lung cancer at the Aichi Cancer Center, and controls (n=230) were recruited from visitors to the outpatient department of the Aichi Cancer Center and matched to cases by age (within 5 years) and sex. We genotyped polymorphisms in five genes: pancreatic lipase (PNLIP, rs2915748), apolipoprotein E (APOE, rs440446), hepatic lipase (LIPC, rs1800588), fatty acid desaturase 1 (FADS1, rs174546), and FADS (rs174570). Odds ratios (OR) and 95% confidence intervals (95% CI) were evaluated with unconditional logistic regression. After adjustment for age, sex, BMI, cigarette smoking (pack-years), a promoting effect was observed for the variant allele of PNLIP rs2915748 [OR (95%CI): 1.64 (1.09-2.47) for GA/AA vs. GG]. A similar effect was found for APOE rs440446 [OR (95%CI): 1.71 (1.14-2.58) for CG/GG vs. CC)]. No significant associations were detected for other three sequence variants examined. To our knowledge, our study is among the first to suggest that genetic variations in the digestion and transport of lipids alter lung cancer risk.

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 888. doi:10.1158/1538-7445.AM2011-888
Abstract 889: An analysis of single nucleotide polymorphisms of 125 DNA repair genes in the Texas genome-wide association study of lung cancer with a replication for the XRCC4 SNPs
Authors: Yu Hongping , Zhao Hui , Wang Li-E , Han Younghun , V. Chen Wei , Amos Christopher I. , Rafnar Thorunn , Sulem Patrick , Stefansson Kari , Landi Maria Teresa , Caporaso Neil , Albanes Demetrius , Thun Michael , McKay James D. , Brennan Paul , Wang Yufei , Houlston Richard S , Spitz Margaret R. , Wei Qingyi
Published: June 2012

DNA repair genes are important for maintaining genomic stability and limiting carcinogenesis. We analyzed all single nucleotide polymorphisms (SNPs) of 125 DNA repair genes covered by the Illumina HumamHap300 (v1.1) BeadChips in a previously conducted genome-wide association study (GWAS) of 1,154 lung cancer cases and 1,137 controls and replicated the top-hits of XRCC4 SNPs in an independent set of 597 cases and 611 controls in Texas populations. We found that six of 20 XRCC4 SNPs were associated with a decreased risk of lung cancer with a P value of 0.01 or lower in the discovery dataset, of which the most significant SNP was rs10040363 (P for allelic test = 4.89 ×10−4). Moreover, the data in this region allowed us to impute a potentially functional SNP rs2075685 (imputed P for allelic test = 1.3 ×10−3). A luciferase reporter assay demonstrated that the rs2075685G>T change in the XRCC4 promoter increased expression of the gene. In the replication study of rs10040363, rs1478486, rs9293329, and rs2075685, however, only rs10040363 achieved a borderline association with a decreased risk of lung cancer in a dominant model (adjusted OR = 0.80, 95% CI = 0.62-1.03, P = 0.079). In the final combined analysis of both the Texas GWAS discovery and replication datasets, the strength of the association was increased for rs10040363 (adjusted OR = 0.77, 95% CI = 0.66-0.89, Pdominant = 5×10−4 and P for trend = 5×10−4) and rs1478486 (adjusted OR = 0.82, 95% CI = 0.71 -0.94, Pdominant = 6×10−3 and P for trend = 3.5×10−3). Finally, we conducted a meta-analysis of these XRCC4 SNPs with available data from published GWA studies of lung cancer with a total of 12,312 cases and 47,921 controls, in which none of these XRCC4 SNPs was associated with lung cancer risk. It appeared that rs2075685, although associated with increased expression of a reporter gene and lung cancer risk in the Texas populations, did not have an effect on lung cancer risk in other populations. This study underscores the importance of replication using published data in larger populations.

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 889. doi:10.1158/1538-7445.AM2011-889
Abstract 89: Prostaglandin E2 promotes intestinal tumor growth via DNA methylation
Authors: Xia Dianren , Wang Dingzhi , Kim Sun-Hee , DuBois Raymond N.
Published: June 2012

Evidence for the link between inflammation and cancer comes from epidemiologic and clinical studies showing that use of nonsteroidal anti-inflammatory drugs (NSAIDs) reduce the relative risk for developing colorectal cancer (CRC) by 40-50%. NSAIDs exert some of their anti-inflammatory and anti-tumor effects by targeting cyclooxygenase enzymes (COX-1 and COX-2). COX-2-derived prostaglandin E2 (PGE2) is a pro-inflammatory mediator and promotes tumor progression. Clearly, DNA methylation is one of the critical mechanisms for silencing tumor suppressors and DNA repair genes during CRC initiation and progression. It has been demonstrated that a unique subset of CRC patients with extensive CpG island hypermethylation has unique clinicopathologic features and an exceedingly poor survival. However, all of the mechanisms by which chronic inflammation contributes to carcinogenesis are not understood and the precise role of aberrant DNA methylation in cancer also remains unclear. Here we used colorectal cancer cells to show that PGE2 treatment upregulated the expression of DNA methyltransferase 1 (DNMT1) and 3B (DNMT3B), which resulted to increased DNA methylation in the promoters of target genes O6-methylguanine-DNA methyltransferase (MGMT) and cannabinoid receptor 1 (CB1). Meanwhile, the expression of MGMT and CB1 were decreased. In ApcMin/+ mice, PGE2 treatment also increased the expression of DNMT1 and DNMT3B and the DNA methylation of MGMT and CB1 promoters, and reduced the expression of MGMT and CB1. All these alterations were accompanied by increases in both polyp number and size in the intestines of ApcMin/+ mice. More intriguingly, a combined treatment with a selective COX-2 inhibitor (celecoxib) and a demethylating agent (5-Aza-dC) significantly further reduced the polyp number and size in ApcMin/+ mice in comparison with single agent treatment. These results suggest that PGE2 can silence tumor suppressors and DNA repair genes via DNA methylation to promote tumor formation and progression. These findings uncover a previously unrecognized role for PGE2 promotion of tumor formation and progression.

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 89. doi:10.1158/1538-7445.AM2011-89
Abstract 90: A comprehensive analysis to screen for epigenetically silenced miRNA genes in colorectal cancer
Authors: Suzuki Hiromu , Yamamoto Eiichiro , Nojima Masanori , Shimizu Takashi , Tokino Takashi , Shinomura Yasuhisa , Toyota Minoru
Published: June 2012

Epigenetic alteration plays an important role in inactivating microRNA (miRNA) genes in cancer. In the present study, we performed comprehensive analysis of miRNA expression, histone modification and DNA methylation in order to determine the transcription start sites (TSSs) of miRNA genes as well as to identify epigenetically silenced miRNA genes in colorectal cancer (CRC). We used a CRC cell line HCT116 treated with our without 5-aza-2’-deoxycytidine (DAC) plus 4-phenylbutyric acid (PBA). We also used a HCT116 cells in which DNMT1 and DNMT3B are genetically disrupted (DNMTs KO). For miRNA expression profiling, we used Human miRNA Microarray v1 (Agilent Technologies) and TaqMan MicroRNA Array v2.0 (Applied Biosystems). We carried out chromatin immunoprecipitation (ChIP) using antibodies against trimethyl-histone H3K4 (H3K4me3), trimethyl-histone H3K27 (H3K27me3) or dimethyl-histone H3K79 (H3K79me2). We performed ChIP-on-chip analysis using Human Promoter ChIP-on-chip microarray (Agilent Technologies) and ChIP-seq analysis using SOLiD3plus (Applied Biosystems). DNA methylation was analyzed using methylated-specific PCR (MSP), bisulfite-pyrosequencing and methylated-CpG island amplification microarray (MCAM). miRNA microarray analysis revealed that 187 miRNAs were downregulated in HCT116 cells compared to normal colon, and more than half of the downregulated miRNAs were upregulated by demethylating treatment. By combining miRNA expression and H3K4me3 analysis, we identified presumed TSSs of 173 primary miRNA genes which encode 266 pre-miRNAs. Of the 266 pre-genes, TSSs of 114 genes are located in the proximal upstream (< 5 kb) of pre-miRNA-coding regions, and TSSs of 213 genes are associated with CpG islands (CGIs). Comparison between HCT116 and DNMTs KO cells suggested that 39 primary genes which encode 87 pre-miRNAs are epigenetically silenced in HCT116. Of the 38 genes, TSSs of 24 genes are associated with CGIs, and we observed hypermethylation in all of them. We conclude that the combined analysis of expression, histone modification and DNA methylation is a useful strategy to identify epigenetically silenced miRNA genes in 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 90. doi:10.1158/1538-7445.AM2011-90
Abstract 908A: RAD51C germline mutations in breast and ovarian cancer cases from high-risk families
Authors: Clague Jessica N. , Wilhoite Greg , Adamson Aaron , Weitzel Jeffrey N. , Neuhausen Susan L.
Published: June 2012

Purpose: BRCA1 and BRCA2 account for approximately 80% of cases of hereditary breast and ovarian cancer. Additional genes involved in DNA repair have been identified as predisposing to breast cancer. One such gene RAD51C, essential for homologous recombination repair, has been reported to be a rare breast cancer susceptibility gene. Several pathogenic RAD51C mutations have been identified in BRCA1- and BRCA2-negative breast and ovarian cancer families but not in families with breast cancer alone.

Methods: We performed complete sequencing of RAD51C in germline DNA of 286 female breast and ovarian cancer cases with a family history of breast and ovarian cancer. They had been previously tested for mutations in BRCA1 and BRCA2 and were negative. We screened 133 breast cancer cases, 119 ovarian cancer cases, and 34 with both breast and ovarian cancer. The in-silico SIFT and Polyphen programs were used to predict possible pathogenicity of non-synonomous variants. Two-hybrid screening is currently being performed to assess functionality of four of the non-synonomous variants.

Results: Fifteen DNA sequence variants were identified among the 286 cases; including four intronic, one 5’ UTR, one promoter, three synonymous, six non-synonymous variants. None were truncating. Of these variants, six have been previously identified and have rs numbers, whereas the remaining nine are novel. Nine of the variants were private (seen in one individual) and the other six were detected in more than one individual. Of the six non-synonomous variants, SIFT and Polyphen predicted that two were likely pathogenic, with predictions based on degree of conservation of the affected residue. An additional two non-synonomous variants are in important domains of the protein and may also be pathogenic. We are currently investigating potential functional importance of these four variants through yeast-two-hybrid assays.

Conclusions: Our results provide further evidence that Rad51C is a breast and ovarian cancer susceptibility locus.

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 908A. doi:10.1158/1538-7445.AM2011-908A
Abstract 909: Activation of NF-κB and its downstream targets play a key role in the dramatic induction of hepatocarcinogenesis in metallothionein null mice
Authors: Kaffenberger Thomas , Roy Satavisha , Wang Bo , Costinean Stefan , Frankel Wendy , Bratasz Anna , Kuppusamy Periannan , Hai Tsonwin , Ghoshal Kalpana , Jacob Samson , Majumder Sarmila
Published: June 2012

Hepatocellular Carcinoma (HCC) is one of the most prevalent cancers in the world and the third leading cause of cancer-related death. Although hepatitis C and fatty liver disease appear to be the main risk factors in most western countries other factors including alcohol, tobacco, diabetes, and other metabolic disorders can also increase the likelihood of HCC development. HCC is believed to develop through a tumor promoting mechanism involving inflammation and oxidative stress. We have previously shown that metallothionein (MT), a ubiquitously expressed free radical scavenger, is dramatically downregulated in human and rodent HCCs. To test the hypothesis that MT protects the liver from carcinogenesis by relieving oxidative stress, MT knockout (MTKO) mice were injected with Diethylnitrosamine (DEN), a potent liver carcinogen. When compared to wild-type DEN treated mice, the MTKO groups exhibited significantly higher (5-fold) incidence and an accelerated rate of hepatocarcinogenesis. Gene expression analysis at the preneoplastic stage revealed a dramatic increase in the levels of Serpine-1 in the MTKO mice, which was validated by real-time PCR. Serpine-1, a tissue glycoprotein and an active suppressor of fibrinolysis through the inhibition of tissue plasminogen activator and urokinase plasminogen activator, is also believed to increase cell migration and angiogenesis. Real-time PCR analysis of the pro-inflammatory cytokines known to induce Serpine-1 revealed substantial upregulation of TNF-α, IL-6, and IL-1β in the MTKO/DEN mice compared to the WT/DEN and untreated controls. Electrophoretic mobility shift assay confirmed differential activation of NF-κB, a downstream effector of pro-inflammatory cytokines and inducer of Serpine-1 expression, in the MTKO/DEN mice at the preneoplastic stage. These data demonstrate that Serpine-1 and NF- κB act in concert at the early stages of hepatocarcinogenesis when free radical scavenging is compromised. These data show the protective role of MT against HCC induction in a mouse model and provide the rationale for an alternate therapeutic strategy in HCC therapy.

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 909. doi:10.1158/1538-7445.AM2011-909
Abstract 913: Differential roles of SPARC in bladder carcinogenesis and metastasis
Authors: Said Neveen A. , Frierson Henry , Theodorescu Dan
Published: June 2012

Secreted Protein Acidic and Rich in Cysteine (SPARC), also termed osteonectin and BM-40, exhibits highly regulated expression during normal development, in tissues undergoing remodeling and repair as well as in cancer. The role of SPARC in bladder cancer is still elusive. Therefore, we sought to investigate the differential roles of SPARC in bladder carcinogenesis, progression and metastasis. We developed a chemical carcinogen N-nitrosobutyl(4-hydroxybutyl) amine (BBN) fed to mice with targeted deletion of SPARC (SP−/−) and their wild type counterparts (SP+/+) in drinking water to induce bladder cancer. We found that SP−/− mice exhibited earlier onset of urothelial pathology (inflammation/atypia and dysplasia, P<0.01) that significantly rapidly progressed to carcinoma in situ (CIS, P<0.02) and muscle invasive disease (P<0.03) as compared to their SP+/+ counterparts. SP−/− mice also exhibited significantly higher incidence and frequency of multifocality (kidney involvement, P<0.02) as well as metastases to para-aortic lymph nodes (P<0.04) and lungs (P<0.03) than SP+/+ counterparts. Furthermore, SP−/− mice had significantly lower median survival than SP+/+ counterparts (27weeks versus 40weeks for SP−/− and SP+/+, respectively; P<0.0002). Comparative analysis of bladder tissue lysates harvested from SP−/− and SP+/+ mice with matched pathology and BBN-exposure revealed that the accelerated onset of bladder lesions in SP−/− compared to SP+/+ was due to the effect of SPARC inhibiting cell cycle progression. These effects correlated with increased accumulation of reactive oxygen species concomitant with DNA damage as determined by 8-OH-odeoxyguanosine, lipid peroxidation and increase in markers of protein oxidation, sulfiredoxin and nicotinamide-N-methyl transferase (NNMT). The significant increase in inflammation in SP−/− was associated with significant higher activation of transcription factors AP1 and NFκß compared to SP+/+. These findings indicate SPARC exerts distinct differential roles in modulating tumor-host interactions during the initiation, progression and lung metastasis of bladder 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 913. doi:10.1158/1538-7445.AM2011-913