bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1302: Role of the low-affinity leukotriene B4 receptor BLT2 in VEGF-induced angiogenesis
Authors: Hong Joe Y. , Kim Geun-Young , Kim Jae-Hong
Published: February 2011

The leukotriene B(4) (LTB(4)) receptor BLT2 is expressed in endothelium, but no clear physiological function for it has yet been identified, especially in vascular angiogenesis. The purpose of this study is to characterize the potential function of BLT2 in vascular endothelial growth factor (VEGF)-induced angiogenesis. VEGF significantly upregulates BLT2 expression in human umbilical vein endothelial cells (HUVECs), and BLT2 knockdown by siRNA or inhibition of BLT2 by a specific BLT2 antagonist LY255283 attenuates VEGF-induced angiogenesis, which was determined by its effect on the formation of tube-like structures and on transmigration. The role of BLT2 in VEGF-induced angiogenesis was more evident in vivo, where BLT2 inhibition by LY255283 almost completely blocked VEGF-induced vessel formation in Matrigel-plug assays. In addition, we found that VEGF upregulates synthesis of the BLT2 ligand, 12(S)-hydroxyeicosatetraenoic acid (HETE). siRNA knockdown of 12-lipoxygenase (12-LO) expression attenuates VEGF-induced angiogenesis in HUVECs, and the addition of 12(S)-HETE to the 12-LO knockdown-HUVECs restores VEGF-induced angiogenesis. The activation of BLT2 itself by either 12(S)-HETE or LTB(4) evoked significant angiogenic phenotypes, both in vitro and in vivo. Our findings indicate that BLT2 plays an essential role in mediating VEGF-induced angiogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1302.
Abstract 1309: Inhibition of the ATR/CHEK1 pathway overcomes reduced sensitivity to ionizing radiation associated with distal 11q loss
Authors: Sankunny Madhav , Gollin Susanne M.
Published: February 2011

Genetic changes play a significant role in carcinogenesis. A commonly observed genetic alteration is amplification of chromosomal band 11q13. This has been reported at relatively high frequency in breast, ovarian, head and neck (HNSCC), and lung carcinomas. Previous studies in our lab have shown that the breakage-fusion-bridge (BFB) cycle mechanism responsible for this amplification results in distal 11q loss with concomitant loss of critical DNA damage response (DDR) genes, like ATM, MRE11A, and H2AFX. We showed in HNSCC that distal 11q loss leads to a defective DDR and decreased sensitivity to DNA damaging agents like ionizing radiation (IR). Further, HNSCC, Non-Small Cell Lung Carcinoma (NSCLC), and ovarian carcinoma cell lines with partial copy number loss of distal 11q show reduced sensitivity to IR and overexpression of the ATR/CHEK1 pathway. siRNA knockdown of CHEK1 in carcinoma cell lines with distal 11q loss resulted in 60-70% decreased cell survival in response to a single dose of IR. Cell lines without distal 11q loss did not show differential sensitivity to IR. These findings have led us to investigate whether these cell lines show decreased sensitivity to other DNA damaging agents such as various chemotherapeutic drugs.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1309.
Abstract 1312: Functional significance for an hnRNP A18 signature RNA motif in the 3'UTR of Ataxia Telangiectasia and RAD3 related (ATR) transcript
Authors: Yang Qingyuan , Yang Ruiqing , Zhan Ming , Nalabothula Narasimharao , Carrier France
Published: February 2011

The predominantly nuclear hnRNP A18 translocates to the cytosol in response to cellular stress and increases translation by specifically binding to the 3'untranslated region (UTR) of several mRNA transcripts and the eukaryotic Initiation Factor 4G. Here, we identified a 51 nucleotides motif that is present 11.49 times more often in the 3'UTR of hnRNP A18 mRNA targets than in the unigene data base. This motif was identified by computational analysis of primary sequences and secondary structures of hnRNP A18 mRNA targets against the unaligned sequences. Band shift analyses indicate that the motif is sufficient to confer binding to hnRNP A18. A search of the entire unigene data base indicates that the hnRNP A18 motif is also present in the 3'UTR of the Ataxia Telangiectasia and Rad3 related (ATR) mRNA. Validation of the predicted hnRNP A18 motif is provided by hnRNP A18 binding to ATR 3'UTR and amplification of endogenous ATR transcript on polysomal fractions immunoprecipitated with hnRNP A18 antibodies. Moreover, over expression of hnRNP A18 results in increased ATR protein levels and increased phosphorylation of Chk1, a preferred ATR substrate, in response to UV radiation. To our knowledge, this constitutes the first demonstration of a post-transcriptional regulatory mechanism for ATR activity. hnRNP A18 could thus become a new target to trigger ATR activity as back up stress-response mechanisms to functionally compensate for absent or defective genotoxic stress responders.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1312.
Abstract 1313: SPARC enhances radiosensitivity by inhibiting radiation-induced SOX-4 transcription factor in medulloblastoma
Authors: Chetty Chandramu , Bhoopathi Praveen , Gujrati Meena , Dinh Dzung H. , Rao Jasti S. , Lakka Sajani S.
Published: February 2011

Radiotherapy is frequently applied to control local tumors and works by directly killing tumor cells and inducing apoptosis of tumor vascular endothelial cells. Recently, it has been demonstrated that expression of secreted protein, acidic and rich in cysteine (SPARC), a member of the matricellular family of proteins that modulate cell-cell and cell-matrix interactions, correlates with radio-resistance in several tumor types. We therefore investigated the anti-tumor effects of combining exogenously expressing SPARC full length cDNA with irradiation (IR) on medulloblastoma in vitro and in vivo. We studied a combination response of SPARC overexpression and IR; specifically, we determined cell survival using clonogenic assay, conducted cell cycle analysis using flow cytometry, and assessed apoptosis using TUNEL staining in vitro in D283 and DAOY medulloblastoma cells. We demonstrated that SPARC overexpression prevented IR-induced p53 upregulation and p53 phosphorylation on serine 15. Irradiated tumor cells induced SOX-4-mediated DNA repair gene XRCC1, checkpoints-2, 1 and p53, which were abrogated with combined treatment of SPARC overexpression and IR as determined by western blotting. Further, DAOY orthotopic tumors treated with combined exogenously expressed SPARC and IR showed significantly greater growth inhibition than tumors treated with IR alone. These results suggest that SPARC overexpression in combination with radiotherapy can inhibit SOX-4-mediated DNA repair mechanisms induced by radiation and provide evidence of the anti-tumor efficacy of combining SPARC overexpression with ionizing radiation as a new therapeutic strategy for the effective treatment of medulloblastoma patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1313.
Abstract 1320: Molecular imaging of EMT reveals crosstalk of multiple pathways and provides novel sites for therapeutic intervention of EMT
Authors: Nyati Shyam , Bhojani Mahaveer Swaroop , Keshamouni Venkat , Schinske Katrina , Ross Brian D. , Rehemtulla Alnawaz
Published: February 2011

Ionizing radiation therapy have been also suggested to result in increased incidence of local or distant metastasis which is, at least in part, mediated by TGFß signaling. TGFß is a known potentiator of epithelial to mesenchymal transition (EMT), a complex process by which a tumor cell bolsters its metastatic potential by transmogrifying into a highly motile and invasive cell that is ready to take on the challenge of distant travel and resettlement in a new milieu. Therefore it is important, in order to increase efficacy of ionizing radiation, a combination therapy along with inhibitors of EMT pathway, be utilized in the treatment of cancers. To date there is no clinically relevant EMT inhibitor and therefore to assist in the process of identifying a small molecular weight inhibitor, we developed three distinct non-invasive and quantitative molecular imaging reporters for monitoring EMT. These were based on changes in expression profile of E-cadherin and N-cadherin and complementation of luciferase based TGFβR kinase (BTR) activity. In the lung cancer EMT model studies using TGFβ treated A549 cells we demonstrated a time and dose dependent increase in activity of luciferase reporter driven by N-cadherin promoter and a decrease in the activity of a luciferase reporter driven by E-cadherin promoter. These changes were validated by phenotypic alteration of A549 cells and by western blotting for signaling intermediates of EMT pathway. BTR (bioluminescent TGFβR reporter), was a gain of function sensor of SMAD2/3 phosphorylation wherein inhibition of TGFβR signaling leads to increased reporter activity. Such reporters are extremely useful in high throughput screening (HTS) as cytotoxic agents are eliminated early in the screening process. Treatment of A549 cells stably expressing BTR with SB431542 (TGFβR specific inhibitor) lead to a more than 20 fold increase in BTR activity. All three reporters were adapted for HTS assay and were used to screen a library of known kinase inhibitors. Analyses and validation of hits suggested that the loss of epithelial or gain of mesenchymal phenotypes are independent processes. Further it also highlighted complex cross talks between EMT and different pathways involving mTor, Src, p38 MAPK, Akt, JNK, PI3-K, PKA, PKC, GSK-3β, PDGFRK and EGFR. Efficacy of several lead compounds (Erlotinib, SP600125, SB203580, and SB431542) in combination with radiotherapy is being accessed to increase radiation sensitivity in epithelial cancers.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1320.
Abstract 1321: ERK1/2 show different activity profiles in vitro and in vivo subsequent to NOS inhibition
Authors: Robert Cardnell J G , Mikkelsen Ross B.
Published: February 2011

Nitric oxide (NO) is a crucial mediator of several survival mechanisms in tumor cells. Previous studies demonstrated that ionizing radiation (IR) stimulates NO generation activating pro-survival mechanisms including receptor tyrosine kinase and NF-κB-dependent pathways. In vitro, the IR-induced activation of these pathways survival pathways is inhibited by the NO synthase inhibitor, NG-nitro-L-arginine (L-NNA). Furthermore, the addition of L-NNA to the drinking water of flank xenograft bearing animals slows tumor progression, kills tumor cells and with radiation enhances animal survival. To elucidate the mechanism(s) by which L-NNA acts in such tumors we conducted experiments to study intracelluar signaling pathway activation by L-NNA with and without radiation.

Animals bearing flank xenografts received 10 Gy whole body irradiation either with or without prior L-NNA treatment. Tumors were excised at times post IR up to 30 minutes and protein lysates prepared for analysis by western blot. Cell monolayers were also similarly treated prior to cell lysis and protein analysis.

The activation (phosphorylation) of ERK1 and ERK2 was assayed in cultured monolayers and in flank xenografts using the A431 and FaDu cell lines. In vitro, the addition of L-NNA to the culture medium had little effect upon the activation of either ERK. In vivo however, L-NNA treatment up-regulated the phosphorylation of both ERK isoforms without irradiation and following irradiation elicited a significant enhancement of ERK1 phosphorylation and an inhibition of ERK2.

The current consensus is that ERK1 and ERK2, due to the similarities of their protein sequence, are similarly regulated and in general activate the same substrates. However, recent evidence has emerged to indicate distinct roles for ERK1/2 in addition to their overlapping actions. Indeed, the targeting of ERK2 has been seen to abolish Ras-dependent cell proliferation, an effect not observed with ERK1 targeting. Distinct signaling roles, and the opposite effects we observe upon ERK1 and ERK2 phosphorylation in vivo following L-NNA treatment may explain our previously reported findings of enhanced tumor control. In addition, these findings my shed light upon why ERK inhibitors show only moderate efficacy in clinical trials.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1321.
Abstract 1326: Differential cytokine-related signaling pathways responded to ionizing radiation in two lung adenocarcinoma cell lines
Authors: Liu Yen-Chun , Lu Tzu-Pin , Hsiao Tzu-Hung , Lu Jo-Yang , Hsu Feng-Ming , Cheng Jason Chia-Hsien , Yang Pan-Chyr , Lai Liang-Chuan , Chuang Eric Y , Tsai Mong-Hsun
Published: February 2011

Lung cancer is the leading cause of cancer-related mortality in the world. Metastasis is the leading cause of death and an enormous therapeutic challenge for non-small cell lung cancer. Radiation therapy is a treatment of unresectable lung cancer and may palliate the symptoms, locally control tumor growth, and provide higher survival rate. Yet, the molecular mechanism of radio-sensitivity in lung cancer still remains unclear. Two lung adenocarcinoma cell lines (CL1-0 and CL1-5) with different metastatic potentials were irradiated with 10Gy γ-radiation. CL1-5 showed more radio-sensitive than CL1-0 since the surviving fractions in CL1-5 were ten times lower than CL1-0 by clonogenic assays. Gene expression profiles were also analyzed using microarray in order to better understand differential gene expression between these two cell lines after radiation. Total RNAs for whole genome gene expression analysis were extracted from these two cell lines at 0, 1, 4, 9 and 24 h after 10Gy irradiation. Gene Set Enrichment Analysis (GSEA) revealed the pathways of death, cytokine, cell adhesion, IL1R, NF-κB, and TNFR had differences between these two cell lines following 10Gy radiation exposure. Tumor necrosis factor (TNF) cytokine family and interleukin-1 (IL1) was up-regulated in CL1-5 after irradiation. The expression level of TNF-α validated by quantitative real time PCR was increased in CL1-5 and was not detected in CL1-0. Therefore, TNF-α released into the culture medium in CL1-5 after irradiation might be a death signal to activate the NF-κB pathway and cause more cell death. Moreover, the different responses of NF-κB-related pathways induced by radiation between the two cell lines might contribute the different survival. These cytokine modulations might provide promising targets for further investigation regarding radiation treatment in lung cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1326.
Abstract 1331: BMP-6 induce IL-1β expression levels in macrophage cells
Authors: Jung Yeon Suk , Lee Geun Taek , Lee Jae-Ho , Kwon Seokjoo , Kim Isaac Yi
Published: February 2011

Prostate cancer is the most 2ND leading cause of cancer death among men in United States. In metastatic prostate cancer patients, androgen ablation leads to symptomatic improvement and a decrease in serum prostate-specific antigen (PSA), but in almost patients the disease will eventually become refractory to hormone ablation. Previously, it has been published that IL-1β from macrophage regulates AR dependent signal transduction. In the prostate cancer, Bone morphogenetic protein-6 (BMP-6) levels are elevated than normal prostate. BMPs are members of TGF-β super family that regulates bone formation, hematopoiesis and development. BMP-6 is a pleiotropic growth factor with frequently increased levels of expression in the context of loss of its cognate receptors in prostate cancer cells. In this study, we demonstrated that BMP-6 secretion in CaP affects on macrophage cell line, RAW 264.7. Results showed that BMP-6 increased IL-1β levels in the macrophage and the induction is concentration and time dependent. In association with these observations, it is demonstrated that IL-1β expression by BMP-6 is mediated through ALK3, BMPRII and Smad1/4. Taken together, ERK inhibitor and JNK inhibitor may block IL-1β induction by BMP-6 completely in RAW264.7, macrophage cell line.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1331.
Abstract 1337: Soluble IL-6Rα regulates endothelial survival and vascular integrity and promotes ovarian cancer progression
Authors: Wei Lin-Hung
Published: February 2011

The immunoregulatory cytokine interleukin 6 (IL-6) has been recognized as an important modulator of ovarian cancer progression. However, whether IL-6 plays a direct role in the process remains controversial. On target cells, IL-6 binds to the IL-6 receptor (IL-6Rα) and signals via complex formation with the ubiquitously expressed gp130 receptor. Soluble IL-6 receptor protein (sIL-6Rα) binds IL-6 and can activate target cells that are deficient in or lack IL-6Rα, such as endothelial cells. This process is named trans signaling and serves as the major proinflammatory paradigm of IL-6 signaling under various pathologic conditions, including cancers. In the present report, we showed that sIL-6Rα is significantly elevated in malignant ascites from ovarian cancer patients and is associated with poor prognosis in advanced ovarian cancer patients. We identified that IL-6 trans signaling on endothelial cells prevents chemotherapy-induced apoptosis, induces endothelial hyperpermeability, and increases transendothelial migration of ovarian cancer cells. Selectively blocking the MAPK pathway with the ERK inhibitor PD98059 substantially reduced the IL-6/sIL-6Rα complex-mediated endothelial hyperpermeability. The activation of ERK by the IL-6/sIL-6Rα complex modulated endothelial integrity by initiating the activation of Src kinase activities and Y685 phosphorylation of VE-cadherin. Collectively, these data indicate that sIL-6Rα in malignant ascites of ovarian cancer may drive IL-6 signaling on endothelial cells, which, importantly, is involved in ovarian cancer progression. Specifically, blockage of sIL-6α-mediated signaling may present a promising therapeutic strategy for the management of ovarian cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1337.
Abstract 134: DHA induces apoptosis via lipid rafts modulation and downregulation of EGFR and Akt inactivation
Authors: Kim Yong-Nyun , Lee Eun Jeong , Park Byung-Kiu
Published: February 2011

Lipid rafts are plasma membrane micro-domains that are known to be a depot of various signaling molecules, including EGF receptor. Intact lipid rafts are critical for Akt activation, which is important for cell survival. Therefore, lipid rafts have been involved in regulations of cellular functions such as cell survival and adhesion. (n-3) PUFAs, such as and eicosapentaenoic acid (EPA), are known to influence lipid rafts and have anti-cancer effects. In this study, we hypothesized that DHA induces apoptosis via alteration of lipid rafts-associated survival signaling and we investigated PUFA's anti-cancer effects and a possible mechanism involved in this process using human breast cancer cell line, MDA-MB-231. We found that DHA inhibited the growth of MDA-MB-231 cells up to 50-60% in the presence of DHA in a dose- and time-dependent manner, which was due to apoptosis. Interestingly, DHA treatment down-regulated multiple proteins that are associated with lipid rafts, including EGFR, AKT, Src in their protein levels, and thus inactivated those proteins. DHA stimulated rafts internalization from cell surface to the cytoplasm. DHA attenuated EGF-induced EGFR activation, probably due to EGFR down-regulation. Akt was inactivated with DHA treatment and the over-expression of active-Akt or wt-Akt was able to attenuate cell death by DHA. Cholesterol, a major component of rafts, reversed DHA-induced effects, including lipid raft internalization, Akt inactivation, and apoptosis. All these data indicate that DHA's anti-cancer effect is mediated by rafts internalization and subsequently Akt inactivation. Our study suggests that DHA is a putative modulator of lipid rafts and thus could be developed as an anticancer drug by targeting lipid rafts.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 134.
Abstract 1342: Roles for CD40 ligation in tumor-macrophage interaction and tumor metastasis
Authors: Richardson Katharine S. , George Courtney , Suttles Jill , Stout Robert ,   Department of Microbiology and Immunology and James Graham Brown Cancer Center
Published: February 2011

Macrophages are now known to play multiple roles in the progression and metastasis of many solid tumors. Although tumor-derived cytokines play a role in stimulating cytokine production by the macrophages, the extent of tumor-macrophage cross-talk remains to be explored. We have previously demonstrated that CD154:CD40 interactions are a dominant mechanism of contact-dependent communication between a variety of cell types. We therefore initiated a study of the role of CD154:CD40 interactions in tumor-macrophage interactions. Flow cytometric analysis reveals CD154 expression on 3LLC carcinoma cells. In corroboration of previous studies, co-culture of supernatants of tumor cell cultured with normal macrophages stimulated moderate cytokine production and this was equally effective with both CD40+/+ and CD40-/- macrophages. Co-culture of paraformaldehyde-fixed tumor cells with normal macrophages stimulated cytokine production by the macrophages, indicating that a cell contact dependent mechanism was also involved in the stimulation of macrophages by the tumor cells. Implantation of 3LLC tumors subcutaneously in CD40+/+ and CD40-/- mice resulted in similar growth of the primary tumor mass. However, no lung metastases were detectable in the CD40-/- mice. Bone marrow chimeric mice were generated by reconstituting irradiated CD40+/+ mice with either CD40+/+ or CD40-/- bone marrow. Nine weeks later, the splenic and peripheral blood leukocytes were >94% donor derived. Both recipients of CD40+/+ and CD40-/- bone marrow displayed similar growth of the primary tumor and similar frequency of lung metastases, indicating that CD40 expression by bone marrow derived macrophages was not critical for tumor metastasis. The study demonstrates that ligation of CD40 on hematopoietic and non-hematopoietic cells may play critical roles in tumor progression and metastasis. This research was supported by grants from the Kentucky Lung Cancer Foundation (J.S.) and the Susan G. Komen Race for the Cure (R.S.) and by an NRSA T32 Postdoctoral Training Grant (K.R.) and a Ruth Kirschstein T31 Predoctoral Fellowship (C.G.).

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

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1342.
Abstract 1348: Expression of Bone Morphogenetic Protein-6 closely related to Interleukin-10 in renal cell carcinoma and BMP-6 induced IL-10 in vitro
Authors: Lee Jae-Ho , Lee Geun Taek , Kwon Seok Joo , Kim Wun-Jae , Kim Isaac Yi
Published: February 2011

Primary kidney cancers are the third most common genitourinary tumor in USA in 2008. The majority of kidney tumors (80-85%) are classified as RCC. Since RCCs are generally resistant to chemotherapy and hormonal therapy, only a few therapeutic options are available, such as immunotherapy and molecular targeted therapy when surgical treatment is not available.

Bone morphogenetic proteins (BMPs) are the largest group of proteins in the TGF-β family. BMPs are known to have critical role in the various kinds of developmental processes and frequently over-expressed in the various cancers including prostate, bladder and kidney. Recently, BMP-6 has been reported to play a role in the immune system, inhibit T cell proliferation and activate the macrophages.

Interleukin-10 (IL-10) is a type II cytokine and has anti-inflammatory function in the immune system. It is reported that IL-10 or IL-10 receptor expression is related to the metastasis of RCC.

In this study, we found that BMP-6 expression level is tightly co-related to anti-inflammatory cytokine IL-10 expression (P < 0.001) in 74 human RCC tissue samples. In vitro assay, BMP-6 induced IL-10 in dose and time dependent manners in the mouse peritoneal macrophage and RAW 264.7 cell line. This induction was inhibited by cycloheximide, not by Actinomycin D. IL-10 induction was mediated by the canonical Smad dependent BMP-6 signal pathway. In the IL-10 promoter luciferase activity assay, BMP-RII, ALK-2/3, Smad 5 and Smad 4 were responsible for the BMP-6 induced IL-10 expression. Smad 5 bound to the −800 to −600 region of IL-10 promoter in the ChIP assay. Also Smad-independent STAT3 pathway is required for the IL-10 induction. STAT3 also bound to the −800 to −600 region in ChIP assay and interacted with Smad 5.

In conclusion, BMP-6 expression related with IL-10 in RCC and the direct induction of IL-10 by BMP-6 was observed in macrophages. Thus, BMP-6 seemed to induce IL-10 in RCC and modulated tumor immune environment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1348.
Abstract 1351: Lack of matrix metalloproteinase-10 exacerbates inflammation-associated colon tumor development
Authors: Koller Felicitas L. , Dozier E. Ashley , Fingleton Barbara M.
Published: February 2011

Ulcerative colitis is the most common inflammatory bowel disease, and is associated with increased risk of colon cancer. Understanding the mechanisms by which carcinogenesis occurs in the setting of colitis could lead to both prevention strategies and improved therapies. Matrix metalloproteinase-10 (MMP10), a member of the matrix metalloproteinase family of proteolytic enzymes, is expressed at healing edges of colonic ulcers. Although MMPs are usually considered as destructive players in inflammatory disease, we considered the possibility that MMP10 had a beneficial role in ulcerative colitis. We used dextran sulfate sodium (DSS) treatment in MMP10-null and corresponding control wild-type mice to investigate the consequences of MMP10 deletion on colitis development and recovery. Groups of mice were exposed to DSS for 7-day periods and sacrificed at different timepoints following the cessation of the DSS. Strikingly, MMP10-null mice were more severely affected by the treatment as determined by gross observations such as weight loss and colon length. Histological analysis at the various timepoints indicated that wild-type mice showed almost complete recovery from DSS within 14 days after DSS treatment. In contrast, MMP10-null mice still showed clear signs of damage with persistent inflammatory foci and non-healing ulcers. In situ hybridization indicated MMP10 expression predominantly in inflammatory cells, although some fibroblasts were also positive. Colonic epithelium was negative for MMP10. Bone marrow transplant experiments indicated that wild-type bone marrow partially rescued the MMP10-null phenotype. Measurement of cytokines by ELISA in colonic lavage fluid from MMP10-null and wild-type mice showed that IL-1α was significantly increased in the absence of MMP10. Levels of other cytokines such as TNFα, IL6, IL17 and G-CSF were not different. Multiple exposures to DSS results in conversion of an acute colitis to a chronic inflammatory disease. With only 2 DSS exposures, MMP10-null mice manifested a chronic condition which failed to resolve even after 3 months. Similarly-treated wild-type mice, however, appeared normal at this timepoint. Examination of the colonic tissue from the DSS double exposure showed a significant increase in the number of dysplastic foci present in the MMP10-null mice. Thus, expression of MMP10 appears necessary for resolution of colitis, and in its absence, the development of chronic colitis results in tumor development.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1351.
Abstract 1352: Macrophage specific regulation reveals both pro- and anti-tumor effects of NF-kappaB during mammary tumor progression
Authors: Connelly Linda , Barham Whitney , Onishko Hala M. , Zabuawala T , Ostrowski Michael C. , Blackwell Timothy S. , Yull Fiona E.
Published: February 2011

An increased level of macrophages in human tumors is associated with a poorer prognosis. The transcription factor Nuclear Factor-kappaB (NF-kappaB) is an important regulator of gene expression within macrophages. Recent studies point to a pro-tumorigenic role for NF-kappaB activity in macrophages; however NF-kappaB also regulates expression of genes such as inducible nitric oxide synthase which are associated with anti-tumor effects. We believe that NF-kappaB activity in macrophages can have both anti- and pro-tumor effects depending on tumor stage.

We have developed novel murine models to determine the effects of modulation of NF-kappaB activity specifically within macrophages during primary mammary tumor growth and metastasis. We have used the cfms promoter to specifically express the reverse tetracycline transactivator (rtTA) protein in macrophages. The rtTA can drive tet operon regulated gene expression in the presence of doxycyline (dox). We have used this with a dominant negative IkappaBalpha to inhibit NF-kappaB signaling in the Polyoma mouse mammary tumor model, this model is termed DNFP. We have also used the cfms-rtTA in combination with a constitutively active IKK2 transgene to activate NF-kappaB signaling, this model is termed IKFM.

When NF-kappaB is inhibited in macrophages during primary tumor growth in our DNFP model there is a reduction in primary tumor growth accompanied by a reduced level of lung metastasis. This data suggests that NF-kappaB in macrophages is acting in a pro-tumor manner, in agreement with recently published data. In contrast, we have found that activation of NF-kappaB in macrophages by treating IKFM mice with dox for 1 week before and during two weeks following tail vein injection of polyoma mammary tumor cells leads to a significant reduction in surface lung tumor formation. In additional studies, IKFM mice were pretreated with dox for 1 week but treatment was stopped two days after tumor injection. A similar reduction in tumor number was observed, suggesting an inhibition of cell seeding. Real time PCR analysis of lungs from mice with activation of NF-kappaB in macrophages suggests an anti-tumor “M1” macrophage phenotype.

In summary, our data indicates that NF-kappaB activity in macrophages can have both anti- and pro-tumor effects dependent on tumor stage. This data would suggest that cell specificity and timing of treatment are important considerations with regards to the use of NF-kappaB inhibitors in cancer treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1352.
Abstract 1357: Role of Natural Killer-cell Immunoglobulin-like receptors KIR2DL1 and KIR3DL1 in immune resistance
Authors: Chan Daniel C. , Zhang Zhiyong , Wang Hong , Sui Xiaomei , Chan Tiffany T. , Ahn Natalie , Lanier Lewis L. , Bunn Paul A.
Published: February 2011

Background: The aim of this study is to investigate the mechanism of immune-escape and cancer metastasis by the natural killer (NK) cell immunoglobulin-like receptor (KIRs) subtypes (KIR2DL1 and KIR2DL1) in human lung cancer. We previously reported that metastatic cancer cells acquire immune-resistance by aberrantly expressing KIR on their surface (AACR 2009). In this project we forced expression two of KIR2DL1 and KIR3DL1 plasmids in some H2122-GFP parental lung cancer cells with null expression of KIR and investigated their function in conferring the immune-resistance against NK cell killing.

Method: KIR2DL1 (LL454) and KIR3DL1 (LL456) plasmids were transfected into Phoenix Retroviral Expression system. Virus containing media were used to infect target cells (H2122-GFP) for individual KIR subtype or both KIR subtype expression. Stable transformants were enriched by cell sorting. H2122-GFP parental cells and KIR expressing cells were exposed to various amounts of human normal NK cells or transformed NK-92MI cell line. Anti-proliferative effects by NK cells were accessed with fluorescence intensity in microplate reader. IC50 was determined based on the Effector (NK) / Target Ratio (ETR).

Result: Using cell sorting, single (2DL1 or 3DL1) or double (2DL1 and 3DL1) KIR expressing cells were separated into groups of low, medium and high level of KIR2DL1 or KIR3DL1 expression, based on their fluorescence intensity. When exposed to various amount of normal human NK cells, the parental line was most sensitive to NK killing with an IC50 ETR=2.2, followed by 2DL1-M (4.7), 3DL1-M (5.2), 2DL1-H (7.0), 3DL1-H (9.5), KIR2+ (10.1) and KIR3+(12). Interestingly, the transformed NK-92MI cell line seemed to be more effective than normal human NK cell in killing H2122-GFP and its derivatives and had down shifted the ETR by 10 fold. Nevertheless, the parental line was most sensitive to NK-92MI killing with an IC50 ETR = 0.23, followed by 2DL1-H (0.66), 3DL1-H (1.1), 3D/2DL1-L (1.5), KIR3+(1.8), 2D/3DL1-M (2.00), 2D/3DL1-L (2.20), 3D/2DL1-H (2.60), 3D/2DL1-M (2.90) and 2D/3DL1-H (3.0) respectively. Our data clearly demonstrated that forced expression of KIRs into lung cancer cells confers resistance to NK cytolytic killing and the degree of resistance increases progressively with the level of KIR expression. Double expression of both 2DL1 and 3DL1 in high level in lung cancer cells resulted in higher resistance than the metastatic KIR+3 line.

Conclusion: Aberrant expression of KIR, either by in vivo immune-selection or by forced expression, is responsible for conferring immune-resistance against NK cytolytic killing of human lung cancer cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1357.
Abstract 1363: Inhibition of Neuropilin-1 by anti-Nrp1 results in reduced angiogenesis and inhibition of tumor growth
Authors: Mak Judy , Pan Qi , Berry Leanne , Ross Sarajane , Koeppen Hartmut , Greg Plowman , Watts Ryan , Bagri Anil
Published: February 2011

Neuropilin-1 (NRP1) guides the development of the nervous and vascular systems and has been implicated in modulating various aspects of tumor cell function. We have previously shown that an antibody directed against NRP1 inhibits tumor growth and reduces tumor angiogenesis, as a single agent and more potently in combination with anti-VEGF. However, as NRP1 was also expressed in the tumor cells tested, the impact from inhibiting tumor cell NRP1 in these experiments was unclear. The objective of this study was to determine if inhibition of tumor cell NRP1 was necessary for the observed anti-tumor effects previously described for anti-NRP1. We tested the effects of anti-NRP1 in tumor lines that do not express NRP1, and where expression of NRP1 is restricted to the vasculature. Inhibition of tumor growth as a single agent, and in combination with anti-VEGF in these xenografted tumor lines, confirm that tumor expression of NRP1 is not necessary for the anti-tumor effects of anti-NRP1. We furthermore demonstrate that anti-NRP1 treatment of endothelial cells in in vitro sprouting assays results in potent inhibition of vascular sprout formation, confirming its anti-angiogenic activity. In vivo, in developmental models of angiogenesis, treatment results in reduced angiogenesis that is augmented by anti-VEGF. Finally, we demonstrate that treatment of primates with anti-NRP1 results in up-regulation of cytokines, such as PlGF, that are commonly increased with anti-angiogenic agent treatment. In total, these data confirm that anti-NRP1 mechanistically acts to inhibit tumor angiogenesis, thus resulting in reduced tumor growth and this tumor inhibition is most effective in combination with VEGF inhibition.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1363.
Abstract 1364: Combination of MEDI3617, a fully human anti-angiopoietin 2 monoclonal antibody, with inhibitors of the VEGF pathway enhances antitumor activity in vivo
Authors: Inigo Ivan V. , Coffman Karen , Fazenbaker Christine , Jallal Bahija , Trail Pamela , LaVallee Theresa , Coats Steve , Chang Yong , Leow Ching Ching
Published: February 2011

Angiopoietin 2 (Ang2) is an important regulator of angiogenesis, blood vessel maturation, and maintenance of the integrity of the vascular endothelium. Ang2-Tie2 interactions for vascular remodeling have been shown to play an important role in tumor vessel plasticity. MEDI3617 is a fully human anti-Ang2 monoclonal antibody that neutralizes the activity of Ang2, thereby inhibiting Ang2 from binding and signaling through the Tie2 receptor. Previously, we have demonstrated that treatment with MEDI3617 resulted in tumor growth inhibition in a wide spectrum of subcutaneous human tumor xenograft models. Given that angiogenesis is a process that requires concerted interplay of mutiple pathways, predominantly the VEGF pathway and the Ang/Tie pathway, we hypothesized that maximal inhibition of tumoral angiogenesis and consequently tumor growth could be achieved by blocking both pathways. We investigated the activity and tolerability of combining MEDI3617 with inhibitors of the VEGF pathway such as sorafenib and bevacizumab. In PLCPRF/5, a hepatocellular carcinoma xenograft model, combination of MEDI3617 and sorafenib resulted in a significant increase tumor growth inhibition. Similarly, in HPAC, a pancreatic cancer xenograft model, combination of MEDI3617 and bevacizumab resulted in greater tumor growth inhibition than either single agent alone. Mice exhibited no adverse effects or wt. loss following combination treatments. Taken together, these data support the clinical evaluation of the combination treatment of MEDI3617 and a VEGF inhibitor in cancer patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1364.
Abstract 1367: The dual selective VEGFR-FGFR kinases inhibitor E-3810 decreases tumor perfusion and inhibits tumor growth: an analysis using dynamic contrast-enhanced magnetic resonance imaging
Authors: Bichat Francis , Tizon Xavier , Provent Peggy , Bari Virginie , Cereda Roberta , Camboni Gabriella , Cavalletti Ennio
Published: February 2011

Background: E-3810 is a potent VEGFR1, 2 and 3 and FGFR 1 kinases inhibitor showing potent anti-angiogenic and antitumor activity in several in vitro and in vivo mouse models (Proceedings AACR-EORTC-NCI Meeting, Boston, November 2009; Abstracts No. 252 and 257). The aim of this study was to investigate, in a rat model, the antitumor activity of E-3810 and its anti-angiogenic effects by using DCE-MRI and to correlate the response with a panel of biological markers.

Methods: Nude rats were subcutaneously xenografted with human Calu-6 lung cancer cells and treated orally once daily for 14 consecutive days, either with E-3810 − 10 mpk (dose chosen on the basis of a preliminary study in the same model) or Sorafenib − 100 mpk. Tumor growth and parameters reflecting tumor vascular permeability/perfusion (Ktrans) were evaluated by T2-weighted MRI and by T1-weighted DCE-MRI using Gd-DTPA (Magnevist®) as contrast agent at D-1, D1, D3, D7 and D14. The number, maturity and functionality of tumor vessels were assessed using CD31/α-SMA colocalisation by IHC and injection of Hoechst fluorescent dye on D1, D3, D7 and D14. On the same days, the level of circulating endothelial cells (CEC) and collagen IV were measured by FACS and ELISA assays.

Results: In comparison to vehicle-treated animals, a marked tumor growth inhibition was observed in E-3810-treated rats (max T/C 21%) with no remarkable signs of toxicity. In the same animals, Ktrans value in the tumor rim was significantly decreased (up to 49% on D14). This DCE-MRI finding was supported by the significant decrease in the Hoechst stained area observed at D1 (−97%), D7 (−96%) and D14 (−75%). In addition, the number of tumor vessels (both CD31 and colocalized CD31/α-SMA) was significantly decreased at D3 (−72%), D7 (−68%) and D14 (−86%) in E-3810-treated rats. Always in comparison to vehicle group, no significant changes in CEC were observed after treatment with E-3810, whereas collagen IV levels significantly increased at D14 (+38). Similar effects on all the above mentioned parameters were observed in Sorafenib treated animals. Conclusions: E-3810 displayed a marked antitumor activity in the model of Calu-6 tumor bearing nude rats. The antitumor effect is coupled with a strong antiangiogenic activity, as indicated by decrease in vascular permeability/perfusion and decrease of microvessels density that occur early on and are maintained throughout the treatment period.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1367.
Abstract 1368: L-5F, an ApoA-I mimetic peptide, inhibits tumor angiogenesis by suppressing VEGF/bFGF signaling pathways
Authors: Gao Feng , Su Feng , Roberts Svetlana , Grijalva Victor , Reddy Srinivasa T. , Farias-Eisner Robin
Published: February 2011

Objective

We recently demonstrated that overexpression of ApoA-I inhibits tumor growth and improves survival in mice. In the present study we examined whether apoA-I mimetic peptide, L-5F reduces tumor development in mice by inhibiting angiogenesis.

Methods

Flank tumors were generated in immunocompetent C57BL6/J mice as described previously (Zhang L, et al. 2002) by injecting ID8 cells, a mouse ovarian cancer cell line. L-5F was injected s.c. once a day for 5 weeks (10 mg/kg). 3D vessel images of tumor tissues were created using a micro-CT scanner from Numira Biosciences. The effects of L-5F in vitro were studied in human umbilical vascular endothelial cells (HUVEC) following VEGF and bFGF treatment. MTS assay, BrdU cell proliferation assay, wound-healing assay, and trans-well assay were used to determine cell viability, proliferation, migration, and invasion of HUVEC, respectively. Activation of Erk and Akt pathways were analyzed using western blots.

Results

Daily s.c. injection of L-5F significantly reduced tumor size and quantity and size of vessels of flank tumors in C57BL6/J mice, compared to mice that did not receive L-5F peptide. L-5F (10 µg/ml) significantly inhibited both VEGF- and bFGF-induced cell viability (∼46% for VEGF and ∼56% for bFGF), proliferation (∼50% for VEGF and ∼70% for bFGF), migration (∼80% for VEGF and ∼77% for bFGF), and invasion (∼65% for VEGF and ∼44% for bFGF) in HUVECs. L-5F mediated effects were dose-dependent between 1 and 10 µg/ml including the inhibition VEGF and bFGF-induced phosphorylation of Erk and Akt. L-5F did not affect the viability and proliferation of HUVECs in the basal state (i.e. absence of VEGF and bFGF treatments).

Conclusion

Our data suggest that apoA-I mimetic peptide, L-5F inhibits tumor development in mice, in part, by inhibiting angiogenesis. ApoA-I mimetic peptides may serve as novel anti-angiogenesis and anticancer therapies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1368.
Abstract 1375: Amlexanox inhibits FGF-mediated paracrine and autocrine activity of tumor-derived melanoma cell lines and cell strains
Authors: Huang Ruea-Yea , Bowers Dawn , Wong Michael K.
Published: February 2011

Melanoma is a highly invasive disease characterized by widespread lymphatic and systemic metastases. Although angiogenesis is critical for this to occur, the responsible mechanisms within melanoma cells remain unclear. The purpose of this study is to identify factors secreted by tumor-derived melanoma cells which can mediate these processes. Serum-free conditioned medium (CM) isolated from two melanoma cell lines and four newly derived melanoma cell strains promote both the growth in culture and angiogenic outgrowth activity of HUVEC and HMEC1 in 3-dimensional (3-D) collagen gel culture. Substantial amounts of both FGF1 (acidic) and FGF2 (basic) are found in the conditioned medium (CM). The addition of neutralizing antibodies to FGF1 (5 μg/ml) and FGF2 (3 μg/ml) to the melanoma CM significantly decreased the proliferation of HUVEC and HMEC1 by (20%) and (40%), respectively, and the angiogenic activity of HMEC1 by (20%). Amlexanox (AMX) is an anti-inflammatory agent that binds intracellular S100A13, one component of the putative FGF1-secretion complexes. AMX suppresses constitutive release of FGF1, but not FGF2, from these melanoma cells. AMX-treated melanoma-CM results in significant reduction of: HUVEC mitogenic activity, endothelial migration into 3-D collagen gel as well as melanoma cell proliferation. These AMX-mediated effects correlate with a concomitant decrease of FGFR1 phosphorylation in melanoma cells. The sum of these results point to the importance of the FGF-1 pathway and nominate AMX as a significant anti-melanoma agent by virtue of its impact on both paracrine and autocrine activity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1375.