bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4503: BAY 87-2243, an inhibitor of HIF-1α activation and stabilization, showed promising anti-tumor efficacy either as monotherapy or in combination with anti-VEGF and chemotherapy agents in preclinical tumor models
Authors: Berhoerster Kerstin , Ellinghaus Peter , Haerter Michael , Greschat Susanne , Wengner Antje , Scholz Arne , Haegebarth Andrea , Hess-Stumpp Holger
Published: June 2012

Hypoxia is a hallmark of solid tumors and is associated with local invasion, metastatic spread and resistance to radio- as well as chemotherapy (Vaupel et al., 2004). Furthermore, hypoxia constitutes an independent negative prognostic factor in a diverse range of malignant tumors (Harris, 2002; Vaupel et al., 2004). The cellular adaptation to hypoxia is mediated by a heterodimeric transcription factor hypoxia inducible factor-1 (HIF1). HIF-1α, one subunit of HIF, is constitutively degraded under normoxic conditions, but is stabilized and activated in hypoxic regions of tumors. Nuclear activated HIF-1 controls the expression of >100 genes involved in cellular energy metabolism, neoangiogenesis, anti-apoptotic and pro-proliferative mechanisms promoting invasion and metastasis. It was our hypothesis that small-molecule inhibitor that prevent stabilization and activation of HIF-1 may act as valuable novel cancer therapeutics.

Recently, we identified BAY 87-2243 as a small molecule inhibitor of hypoxia-induced HIF-1 activation that specifically suppressed hypoxia-induced HIF-1α stabilization and expression of HIF target genes. Here we present preclinical anti-tumor efficacy of BAY 87-2243 in several xenografts, both as single agent and in combination with standards treatments.

BAY 87-2243 dosed orally as single agent demonstrated moderate to high tumor growth inhibition in several subcutaneous tumor models of various histological type such as prostate carcinoma, lung carcinoma, neuroblastoma, colorectal and mammary carcinomas. BAY 87-2243 dosed continuously in combination with the anti-angiogenic agent bevacizumab produced long-term tumor growth control or tumor stasis of either small or large established subcutaneous and orthotopic lung carcinoma xenografts (NSCLC H460 model). In an orthotopic pancreatic carcinoma model (DAN-G) a combination of BAY 87-2243 and gemcitabine resulted in a synergistic improvement of the median survival as compared to either agents alone (p=0.0004). In general, BAY 87-2243 was well tolerated in mice without any significant body weight loss. These promising preclinical results suggest that inhibition of HIF-1 by BAY 87-2243 is an innovative approach to cancer therapy with the potential to overcome hypoxia/HIF-induced tumor resistance mechanisms.

Harris AL (2002) Hypoxia-a key regulatory factor in tumor growth. Nat Rev Cancer 2: 38-47

Vaupel P, Mayer A, Hockel M (2004) Tumor hypoxia and malignant progression. Methods Enzymol 381:335-354

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 4503. doi:10.1158/1538-7445.AM2011-4503
Abstract 4516: SC-2001, a SHP-1 enhancer, induces apoptosis in hepatocellular carcinoma through SHP-1 dependent STAT3 inactivation
Authors: Chen Kuen-Feng , Su Jung-Chen , Chen Wei-Lin , Liu Chun-Yu , Cheng Ann-Lii , Chen Pei-Jer , Shiau Chung-Wai
Published: June 2012

The activation of signal transducers and activators of transcription 3 (STAT3) signaling cascade plays a role in regulating cell survival, proliferation, and angiogenesis in various types of cancer, including hepatocellular carcinoma (HCC). Agents that can suppress STAT3 pathway have potentials for the treatment of HCC. Here, we investigated the effects of SC-2001 ((Z)-2-((3-methoxy-2H-pyrrol-2-ylidene)methyl)-1H-pyrrole), a compound from bacterium on HCC. We found that SC-2001 down-regulated the phosphorylation of STAT3 (Tyr 705) and subsequently inhibited transcriptional activities of STAT3. Downstream molecules, driven by STAT3 were repressed by SC-2001. In addition, ectopic expression of STAT3 in HCC cells abolished the prominent apoptotic death in cells treated with SC-2001, indicating that STAT3 is indispensable in mediating drugs’ effects. Importantly, SC-2001 enhanced the expression of SHP1, a negative regulator of STAT3. Knockdown of SHP-1 by small interference RNA, but neither SHP-2, nor PTP-1B, reduced apoptotic effects of SC-2001, indicating SHP-1 played a key role in mediating SC2001-induced cell death. In conclusion, our results suggest that SC-2001 induced apoptosis in HCC, and this effect is mediated through a through SHP-1-dependent STAT3 inactivation.Further clinical investigations of SC-2001 may be warranted. Supported by NSC98-2314-B-002-067-MY3, NSC98-3112-B-002-037, and NSC-99-2314-B-002-017-MY2

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 4516. doi:10.1158/1538-7445.AM2011-4516
Abstract 4530: Pralatrexate-induced apoptosis in multiple myeloma cells correlates with RFC-1 and DHFR expression
Authors: Mangone Michael , Marchi Enrica , Scotto Luigi , O'Connor Owen A. , Cho Hearn J.
Published: June 2012

Pralatrexate (PDX, 10-propargyl 10-deazaaminopterin) is a novel anti-folate agent that is approved for use in relapsed peripheral T cell lymphoma (PTCL). It is distinguished from the parent drug methotrexate (MTX) by having significantly greater affinity for the reduced folate carrier (RFC)-1, the principle transporter that internalize anti-folates, as well as broader efficacy, which strongly suggests that PDX has mechanisms of action beyond inhibition of nucleotide synthesis. Given the activity of PDX in aggressive lymphoid malignancies such as PTCL, we examined the activity of this agent in preclinical models of multiple myeloma (MM), a plasma cell malignancy that is currently incurable. We examined the cytotoxic activity of anti-folates in vitro against a panel of human multiple myeloma cell lines (HMCL) and showed that PDX induced dose-dependent apoptotic cell death in a subset of these. In sensitive cell lines (MM.1s and ARH-77) PDX demonstrated significantly greater potency at 48 hours compared to MTX (LD50 PDX = 2-3 nM vs. LD50 MTX = 25-30 nM). PDX also induced apoptosis in a polyclonal population of primary myeloma cells isolated from a patient specimen, whereas MTX had no effect on viability in these cells. PDX-induced apoptosis in sensitive HMCL was characterized by cleavage and activation of caspase-3 and -9, accompanied by the loss of the anti-apoptotic Bcl-2 family protein Mcl-1. Quantitative RT-PCR analysis of a panel of folate metabolism genes, including RFC-1, folyl polyglutamate synthetase (FPGS), gamma-glutamyl hydrolase (GGH), thymidylate synthase (TS), and dihydrofolate reductase (DHFR) revealed that RFC-1 expression was significantly higher in sensitive HMCL compared to resistant. Dose-dependent up-regulation of DHFR protein expression was observed by western blot in PDX-resistant cell lines, but not in PDX-sensitive ones. Incubation of HMCL with the proteasome inhibitor bortezomib or the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA), both of which demonstrate activity in MM, did not affect expression of RFC-1 in PDX-resistant HMCL and did not synergize with PDX to induce apoptosis in vitro. These results demonstrate that PDX induces apoptosis in sensitive HMCL, and that RFC-1 expression and DHFR up-regulation are functional biomarkers for susceptibility to this anti-folate. These data support further exploration of PDX therapy in MM, including combination therapy with agents that can increase expression of RFC-1 and/or block up-regulation of DHFR.

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 4530. doi:10.1158/1538-7445.AM2011-4530
Abstract 4559: Herceptin trimers linked by EDC could boost direct tumor cell death and overcome resistance to trastuzumab treatment via programmed tumor cell necrosis
Authors: Hu Jiemiao , Liu Xinli , Huang Qianrong , Zhang Boyu , Hughes Dennis PM , Chandra Joya , Xia Xueqing , Li Shulin
Published: June 2012

The human epidermal growth factor receptor 2 (Her2) is overexpressed in multiple types of tumors, including breast tumors and osteosarcoma. Tumor-targeted antibody therapy is one of the safest therapeutics available, but it is often ineffective in treating primary and acquired antibody-resistant tumor cells via indirect tumor cell death and inducing direct tumor cell death. This study reveals that Herceptin conjugates, if generated via the crosslinker EDC (1-ethyl-3-(3-dimethylaminopropyl) carbodimide hydrochloride), is capable of causing Her2 positive tumor cell death. Using an HPLC system, two peaks with estimated molecular weights of antibody dimers and trimers were isolated. The Herceptin dimer and trimer separated by HPLC, especially the trimer, induces significant levels of necrotic tumor cell death. Unlike SMCC conjugated Herceptin, this study indicates that the EDC-conjugated Herceptin overcomes the acquired resistance. The Herceptin trimer is more effective than the dimer in enhancing Herceptin-resistant tumor cell death. Surprisingly different from the known cell death mechanism often resulting from antibody treatment, the Herceptin trimer causes effective and direct tumor cell death via a novel cell death mechanism: programmed cell necrosis. Inhibition of RIP, a critical regulator of programmed necrotic cell death, reversed the Herceptin trimer-induced cell death. In summary, the Herceptin conjugate especially trimer linked by EDC could overcome Her2 positive breast cancer or osteosarcoma cells as well as the resistant cell lines via program cell necrosis cell death. This conjugate has great potential for overcoming the tumor cell resistance to the Herceptin treatment.

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 4559. doi:10.1158/1538-7445.AM2011-4559
Abstract 4560: Anti-tumor activity of a fully human anti-CD27 monoclonal antibody in a transgenic mouse model
Authors: Thomas Lawrence J. , He Li-Zhen , Forsberg Eric M. , Vitale Laura , Boyer James M. , Jones Kristen L. , Weidlick Jeffrey , Glennie Martin J. , Keler Tibor , Marsh Henry C.
Published: June 2012

The costimulatory molecule CD27 is a member of the TNF receptor superfamily, and is constitutively expressed on the majority of mature T cells, memory B cells, and a portion of NK cells. The interaction of CD27 with its ligand CD70 plays an important role in the activation, proliferation, survival, and maturation of effector capacity and memory in T cells; in clonal B cell expansion and germinal center formation; and in NK cell cytolytic activity. Previous published work demonstrated that agonistic anti-mouse CD27 mAbs, given without a DC maturation signal, have potent anti-tumor activity through boosting of T cell immunity. To explore the therapeutic potential of this target, a panel of fully human antibodies recognizing human CD27 was generated using human Ig transgenic mice immunized with recombinant CD27. These anti-CD27 mAbs showed specific and high affinity binding to recombinant CD27 and CD27-expressing lymphoma cells. Human CD27-transgenic (hCD27-Tg) mice were generated to evaluate the anti-CD27 mAbs in vivo. The CD27-Tg mouse line was back-crossed onto a Balb/c background in order to assess anti-tumor activity using the BCL1 B-lymphoma line. Approximately 107 BCL1 cells were delivered i.v. to backcrossed animals on day 0. Doses of 150 to 600 ug of our lead anti-CD27 mAb (clone 1F5) were delivered to mice i.p. on days 3, 5, 7, 9 and 11. In multiple experiments, tumor growth in mice treated with the anti-CD27 mAb 1F5 was substantially delayed compared to that of control-treated mice. Further, many anti-CD27 treated animals did not show evidence of tumor growth several weeks past the point where all control animals had been euthanized. These data confirm that anti-human CD27 mAbs can mediate similar anti-tumor effects as the anti-mouse CD27 agonist antibodies. The 1F5 antibody was also demonstrated to cross-react with CD27 from cynomolgus monkeys, and in a small pilot study was well tolerated and without evidence of significant lymphocyte activation. Taken together the data support the therapeutic potential of this anti-CD27 mAb to enhance immune responses in cancer 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 4560. doi:10.1158/1538-7445.AM2011-4560
Abstract 4573: Inhibition of tumor growth by human IgM-isotype monoclonal antibody to ganglioside GD2
Authors: Krauthauser Candice , Nicolaides Nicholas , Lin JianMin
Published: June 2012

Monoclonal antibody, MORAb-028, a human IgM derived from patients with melanoma, specifically binds to tumor cell surface ganglioside-GD2 with high specificity, and kills GD2-expressing target cells via complement-mediated cytotoxicity (CDC). This CDC-mediated anti-tumor activity of MORAb-028 has been confirmed in vitro using various GD2-expressing tumor cells in presence of rat sera.

In the present study, intraperitoneal (i.p) and intratumoral (i.t.) treatment models in nude rats were developed to investigate in vivo anti-tumor activity of MORAb-028. These compartmental models provide an in vivo system to monitor IgM anti-tumor activity that has not been possible in previous studies due to the rodent poly-Ig-Receptor (PIgR) that is able to sequester systemically administered hIgM in the liver thereby lowering serum IgM steady-state levels that in turn lowers distribution of IgM to targeted tumors.

In the present study, murine EL4-luc2 cells that express high levels of GD2 were engineered to express a luciferase-reporter-gene enabling in vivo bioluminescent detection for monitoring tumor status. These cells were used in two different models to test the ability of MORAb-028 to impact tumor growth.

An i.p. model was developed whereby tumor cells were injected directly into the peritoneal cavity of nude rats followed immediately by a single i.p. dose of MORAb-028 at 3mg/kg, a dose that has showed activity in vitro. Tumor progression was monitored by bioluminescence using IVIS living imaging system. On day 24 post treatment, a significant reduction in tumor progression was observed in the MORAb-028-treated animals in comparison to the control. Only minimal tumor growth (∼3 to 5 mm3) was observed in MORAb-028-treated animals in contrast to control animals, in which tumor occupied the entire peritoneal cavity.

In a second model EL-4-luc cells were implanted subcutaneously and antibody was directly administered to palpable tumors. Here, a single intratumoral injection of MORAb-028 was administered into established (300-400 mm3) tumors. Results showed that MORAb-028 treatment significantly inhibited tumor growth and eradicated nearly the entire tumor in ∼30% of the animals. Six days post treatment the tumor volume in MORAb-028-treated animals was ∼250 mm3, whereas the tumor volume was >1500mm3 in control animals. Animals with eradicated tumors showed no sign of recurrence at day 30 when the study was terminated.

These data indicate that MORAb-028 is a potent agent to treat GD2-positive tumors in rat models. These results also suggest that this antibody may be useful in clinical applications for the treatment of GD2-positive human cancers.

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 4573. doi:10.1158/1538-7445.AM2011-4573
Abstract 4588: Tumor distribution of anti-neuropilin-1 is affected by antibody dose level in a tumor xenograft mouse model
Authors: Bumbaca Daniela , Boswell Charles A. , Mundo Eduardo E. , Xin Yan , Xiang Hong , Port Ruediger E. , Schweiger Michelle G. , Stainton Shannon L. , Bagri Anil , Theil Frank P. , Fielder Paul J. , Khawli Leslie A. , Shen Ben Q.
Published: June 2012

Neuropilin-1 (NRP1) is a VEGF165 and semaphorin receptor widely expressed by vascular endothelial cells in normal tissues and on some tumor cells. Blocking NRP1 with human IgG1 against its b domain has been shown to inhibit tumor growth in several preclinical models. The objective of this study was to assess tumor distribution of anti-NRP1 at different dose levels with the aim of supporting the clinical development of this antibody. Nude mice bearing HM7 tumors were administered [111In]-DOTA labeled anti-NRP1 in the presence of increasing amounts of unlabeled anti-NRP1 via single IV injection. Following dosing, blood and tumors were collected at pre-selected time points. Tumor distribution was evaluated by measuring the radioactivity levels in the tumor and blood samples using a gamma counter. The mice that received only the radiolabeled antibody had relatively low plasma and tumor radioactivity levels at all time points. The plasma and tumor radioactivity levels for all other dose groups were higher than those of the group that received only radiolabeled antibody due to the saturation of the normal tissue sink previously identified. Comparing the tumor to blood radioactivity ratios demonstrated that the different dose groups maintained maximum exposure in the tumor for variable lengths of time, depending on the dose level. At 24 hours post-dose, all doses greater than the radiolabeled antibody alone were able to maintain maximum exposure. Conversely, at 48 hours post-dose, doses ≥ 10 mg/kg were able to maintain that level, while at 120 hours post-dose, only doses ≥ 20 mg/kg were able to maintain maximum exposure. Taken together, this suggests that tumor distribution is both dose and time dependent. This approach has been used to aid the clinical dose selection for anti-NRP1 and may be a valuable tool for the clinical development of other targeted therapies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4588. doi:10.1158/1538-7445.AM2011-4588
Abstract 4591: Comparison of the inhibitory effects of unmodified and modified combinations of chemopreventive agents on MIA PaCa-2 and Panc-1 human pancreatic cancer cell lines
Authors: Sutaria Dhruvitkumar , Huang Ying , Prabhu Sunil
Published: June 2012

Pancreatic cancer is the fourth leading cause of death in the United States with approximately 40,000 estimated deaths in 2010. The objective of our study was to compare the effectiveness of chemopreventive combination regimens of aspirin, curcumin and sulforaphane (ACS) administered in unmodified (free drug) and in modified forms, encapsulated within solid lipid nanoparticles (SLNs), on the MIA PaCa-2 and Panc-1 human pancreatic cancer cell lines. MTS cell proliferation and apoptosis assay studies were conducted on cultured cells. For the MTS assay, upon 75 % confluence, 2.5 × 103 cells for MIA PaCa-2 and 4 × 103 cells for Panc-1 were transferred into each well of 96-well plates. The ACS chemopreventive agents alone or in combination were added to the cells and incubated for 72 h. Absorbance was recorded at 490 nm using an ELISA plate reader. For the apoptosis assay, 3 × 105 cells were cultured in 6-well plates for both Panc-1 and MIA PaCa-2 cell-lines. ACS, individual or combinations, were added and the plates were incubated for 72 h. Cells were analyzed using flow cytometry, measuring the fluorescence emission at 530 nm (FL1) and >575 nm (FL3). IC50 values obtained for the respective unmodified and modified forms of aspirin were (2.05mM/L; 66.08µM/L), curcumin (16.05µM/L; 4.93µM/L) and free sulforaphane at 11.82 µM/L for MIA PaCa-2 cells. Similarly, for Panc-1 cells, the IC50 values for unmodified and modified aspirin were (2.42mM/L; 90.23µM/L), curcumin (24.01 µM/L; 7.5µM/L) respectively and free sulforaphane at 17.81µM/L. For MIA PaCa-2 cell line, unmodified combinations of aspirin (1mM/L) with curcumin (10µM/L) and sulforaphane (5µM/L) showed significant reduction in cell viability of >60% using MTS assay. In comparison, aspirin SLN (25µM/L), curcumin SLN (2.5µM/L) and free sulforaphane (5µM/L) mixtures showed cell viability of >55%. Flow cytometry analysis demonstrated apoptosis of 63% (unmodified) and 50% (modified) for the combinations, at the same concentration ranges as above. For the Panc-1 cell line, treatment with similar concentrations of unmodified and modified SLN combinations showed a >75% and >60% decrease in cell viability (MTS assay) and 63% and 54% induction of apoptosis cells, respectively. Our results demonstrated that the drugs when encapsulated in SLNs at lower concentrations exhibited decreasing cell proliferation and increased induction of apoptosis within the pancreatic cancer cell lines. This data provides compelling evidence of the potential of the SLN carrier system in designing in-vivo studies for the pancreatic cancer chemoprevention.

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 4591. doi:10.1158/1538-7445.AM2011-4591
Abstract 4605: Consumption of S-allylcysteine inhibits the growth of human non-small cell lung carcinoma in a mouse xenograft model
Authors: Tang Feng-Yao , Chiang En-Pei Isabel , Pai Man-Hui
Published: June 2012

Lung cancer is one of the leading causes of cancer death in the world. Human non-small cell lung carcinoma (NSCLC) accounts for almost 80 percent of lung cancer cases. Aberrant phosphoinositide 3-kinase (PI3K)/ Akt /mTOR signaling pathways play important roles and have been widely observed in the development of NSCLC. Previous studies indicated that garlic extracts such as diallyl disulfide (DADS) and diallyl trisulfide (DATS) could inhibit the proliferation of several types of cancer in vitro. However, the inhibitory effects of S-allylcysteine (SAC) on the growth of NSCLC have not been demonstrated yet. Therefore, we investigated whether consumption of SAC could prevent the growth of NSCLC in both in vitro and in vivo models. In the current study, SAC significantly inhibited the proliferation of human NSCLC A549 cells in vitro. Treatment of NF-κB inhibitor, Bay-11-7082, could significantly inhibit the proliferation of NSCLC A549 cells. Our results demonstrated that SAC significantly suppressed the activation of mTOR, NF-κB and cyclin D1 molecules in vitro. Furthermore, our results demonstrated that consumption of SAC significantly inhibited the growth of highly metastatic human NSCLC cells in tumor bearing mice. Bioluminescence imaging, pathological and immunohistochemical (IHC) staining results also indicated that SAC could effectively suppress the growth and malignant progression of human NSCLC in vivo. The chemopreventive effects of SAC were associated with suppression of mTOR and NF-κB molecules in vivo. These results suggested that SAC could act as an effective agent against the malignant progression of human non small cell lung cancer in both in vitro and in vivo models.

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 4605. doi:10.1158/1538-7445.AM2011-4605
Abstract 4608: Hydrogen sulfide-releasing aspirin inhibits the growth of leukemic Jurkat cells and modulates β-catenin expression
Authors: Gan Zong Yuan , Chattopadhyay Mitali , Kodela Ravinder , Boring Daniel , Crowell James A. , Kashfi Khosrow
Published: June 2012

Introduction: Acute leukemia is the primary cause of cancer-related mortality in children. ß -catenin, a regulator of cell-cell adhesion and transcription, is expressed in T-acute lymphoblastic leukemia cells, tumor lines of hematopoietic origin and primary leukemia cells but not in normal peripheral blood T cells. ß -catenin may promote leukemia cell proliferation, adhesion, and survival. Hydrogen sulfide-releasing aspirin (HS-ASA) is a novel compound with significant potential for the control of cancer. It consists of a traditional ASA molecule covalently bound to an H2S-releasing moiety (5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione). Here we examined the effect of HS-ASA on the growth of Jurkat T-acute lymphoblastic leukemia cells and on the fate of ß -catenin.

Methods: HS-ASA was synthesized and purified at our lab with 1H-NMR verification. Cell line: Jurkat T-leukemia. Quantification of cell growth: MTT assay. Cell kinetics: cell cycle phase distribution by flow cytometry; apoptosis by subdiploid (sub-G0/G1) peak in DNA content histograms; and proliferation by PCNA. ß-Catenin and caspase-3 expression was assayed by immunoblotting in cells treated with HS-ASA at 24 hr. Caspase-3 enzyme activity, and H2S levels was also measured.

Results: 1) The IC50 for HS-ASA was 1.5 ± 0.2 µM, whereas that of ASA was >5000 µM strongly suggesting that HS-ASA is at least 3000-fold more potent than traditional ASA. 2) At 0.5xIC50, 1xIC50, and 2xIC50 the following observations were made: Proliferation was inhibited by 88 ± 2%, 63 ± 2%, 42 ± 3%; apoptosis was increased by 15 ± 2%, 39 ± 3%, 54 ± 4%; and cells in the G0/G1 phase increased dose-dependently whereas those in the S and G2/M phases decreased, suggesting a G0/G1 block. 3) HS-ASA dose-dependently reduced the levels of ß-catenin, whereas ASA up to 5 mM had no effect on ß-catenin expression. HS-ASA also increased caspase-3 protein levels and increased its activity dose-dependently, at 0 (no treatment), 0.5xIC50, 1xIC50, and 2xIC50 the values were 3.9 ± 0.3, 12.3 ± 0.5, 23.3 ± 0.7, and 42.6 ± 1.2 pmol/min/mg protein. H2S levels also increased as a function of HS-ASA concentration.

Conclusion: HS-ASA strongly inhibits the growth of Jurkat T cells and causes inhibition of ß-catenin expression. These studies suggest one mechanism by which HS-ASA inhibits the growth of Jurkat T cells.

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 4608. doi:10.1158/1538-7445.AM2011-4608
Abstract 4613: Serum levels of antioxidants in college aged, elderly, and cancer patients
Authors: Bluemel Trevor S. , Sanderson Michael Q. , Jensen Jacob R. , Garrett Andrew R. , Alegre Melissa M. , Robison Richard A. , O'Neill Kim L.
Published: June 2012

Antioxidants are able to prevent the oxidation of biomolecules. Free radicals are oxidants known to be agents which damage DNA. This damage can lead to cancer. Antioxidants neutralize free radicals and are an effective defense system. It has been shown that consumption of fruits, nuts, vegetables, and seeds increases the body's total antioxidant capacity.1 Performing a study that provides data on antioxidant levels in serum will offer insight on potential improvements that can be made in the diets of various populations. In this study we used the oxygen radical absorbance capacity assay (ORAC) to compare serum antioxidant status in three different groups, college age, elderly, and cancer patients. Serum was obtained from 15 college age students (18-21) at Brigham Young University, 15 age matched elderly persons (over the age of 55), and 15 cancer patients. 10 ml of blood was drawn, allowed to clot, centrifuged to separate the cells from the serum, and then diluted to a 1/128 concentration. The ORAC assay was utilized as a way to determine the ability of serum to prevent the oxidation of fluorescein. The results of the experiment surprisingly demonstrate that cancer serum has the highest level of antioxidant status with 99200.97 trolox equivalents per Liter (TE/L) and a standard deviation (STDEV) of 17838.13. The elderly presented the second highest levels of serum antioxidants with 37837.75 TE/L and a STDEV of 7947.08. The college age group had the lowest TE/L with 19051.82 and a STDEV of 2113.36. The elderly compared to the youthful had a p-value < 0.0001, and the cancer patients compared to the healthy possessed a p-value < 0.0001. These results have brought forth more questions than answers. The elderly and cancer patients may have a greater concern for proper dietary intake compared to college age individuals. The cells of the youthful also may be more capable of intaking the antioxidants from the bloodstream. Further studies on these two conclusions may reveal more on the data retrieved.

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 4613. doi:10.1158/1538-7445.AM2011-4613
Abstract 4621: Zfra regulates protein degradation and provides strong prevention against skin cancer
Authors: Chang Nan-Shan
Published: June 2012

Zinc finger-like protein for regulating apoptosis (Zfra) is a 31-amino-acid protein, which participates in the mitochondrial pathway of apoptosis and affects the functions of tumor suppressors WWOX and p53. Here, synthetic full-length Zfra1-31, or truncated Zfra4-10, undergoes ladder-like self-polymerization by greater than 20-100 fold when phosphate ions are present in solutions (without catalytic enzymes). Upon encountering with Zfra, certain cellular proteins become “zfrated” and undergo degradation independently of the ubiquitin/proteasome system. Transiently overexpressed Zfra induces apoptosis of many types of cancer cells. Most strikingly, pre-injection of Zfra1-31 or Zfra4-10 via tail veins protects nude mice from growing cancer xenografts (e.g. melanoma and skin basal cell carcinoma cells). Alteration of Ser8 abolishes self-polymerization and cancer prevention, suggesting an essential role of Ser8 in protein zfration and degradation and cancer prevention.

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 4621. doi:10.1158/1538-7445.AM2011-4621
Abstract 4628: PBISe, an iNOS/Akt inhibitor for colon cancer chemoprevention
Authors: Desai Dhimant H. , Irby Rosalyn , Aliaga Cesar , Amin Shantu G.
Published: June 2012

Colorectal cancer (CRC) is one of the leading causes of premature death in people worldwide. Conversion of normal colonic cells to malignant lesions requires several steps and therefore often proceeds over considerable time periods, on average, 10-15 years, thus providing a window of opportunity for effective intervention and prevention. In 2010 it was estimated that in USA alone about 150,000 people will be diagnosed with colorectal cancer and that about 50,000 people will die of the disease. Today, there is handful of truly effective drugs for colon cancer is available for the patients giving a variety of chemotherapy cocktails. Preventive therapies are promising approach for treatment of cancer, and it has a potential to be a major component of colorectal cancer control. Inducible nitric oxide synthase (iNOS) deregulation and PI3K pathways are such events occurring in colon cancer development. Currently known iNOS inhibitors, such as, S,S’-1,4-phenylene-bis(1,2-ethanediyl)bis-isothiourea (PBIT), require high concentration for clinical efficacy in colon cancer prevention causing systemic toxicity. It is known in the literature that by replacement of sulfur with selenium in the molecule provide a higher inhibitory potency to the compound. Therefore, to develop more potent agent effective at significantly lower concentration, a novel isosteric selenium analog, namely; Se,Se’-1,4-phenylene-bis(1,2-ethanediyl)bis-isoselenourea (PBISe) was developed. Preliminary investigation from our laboratory indicates that PBISe is 25 fold more potent than PBIT in four colon cancer cell lines in MTS assay. Western blot analysis showed decrease pAkt and Akt2 levels, and downstream pPRAS40 levels, and increase in cleaved PARP an apoptosis markers that are specific for Colon cancer. The results from our investigation on maximum tolerated dose (MTD) in FBV mice and male F344 rat when feed with PBISe in a diet as well as tumorigenicity in male (heterozygous) C57BL/6J-APCmin mice and in vitro studies will be discussed. These investigations are highly significant providing insight into the chemoprevention potential and mechanisms based development of PBISe that will inhibit colon cancer. This study was supported by NCI grant CA137763 (DD).

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 4628. doi:10.1158/1538-7445.AM2011-4628
Abstract 4641: Cumulative body burdens of polycyclic aromatic hydrocarbons associate with estrogen bioactivation in pregnant women: Protein adducts as biomarker of exposure
Authors: Lin Po-Hsiung , Wang Tzu-Wen , Tsai Chen-His , Wei Hz-Han , Chen Guan-Jie , Chen Dar-Ren , Chen Shou-Tung , Wang Shu-Li , Lin Che
Published: June 2012

The objective of this research was to develop a biochemical assay to simultaneously analyze protein adducts of quinonoid metabolites of polycyclic aromatic hydrocarbons (PAHs) and endogenous estrogen in pregnant women in Taiwan and to explore the correlations among them. The methodology, which employs trifluoroacetic acid anhydride (TFAA) and methanesulfonic acid (MSA) to selectively cleave cysteinyl adducts, had previously been applied to measure benzene and naphthalene adducts in albumin (Alb). In this study, we refined the assay to allow measurements of both naphthoquinone- and estrogen quinone-derived adducts in serum albumin derived from pregnant women in Taiwan. The isomeric forms of cysteinyl adducts of naphthoquinones, including 1,2-naphthoquinone (1,2-NPQ) and 1,4-naphthoquinone (1,4-NPQ) as well as estrogen quinones, including estrogen-2,3-quinones (E2-2,3-Q) and estrogen-3,4-quinones (E2-3,4-Q), are characterized by using isotopically-labelled bound internal standards after adducts cleavage by the TFAA/MSA derivatization procedure. We applied this method to analyze the background levels of cysteinyl adducts of naphthalene- and estrogen-derived quinones on human serum albumin(Alb)derived from healthy pregnant women (n=40) and their respective umbilical cords (n=40). Results showed that the background levels of cysteinyl adducts of 1,2-NPQ and 1,4-NPQ on human serum albumin were at levels ranging from 89-941 and 33-615 pmol/g, respectively. Logged levels of 1,2-NPQ-Alb were correlated with logged levels of 1,4-NPQ-Alb (correlation coefficient r=0.500, p<0.001). In addition, cysteinyl adducts of E2-2,3-Q-1-S-Alb, E2-2,3-Q-4-S-Alb and E2-3,4-Q-2-S-Alb were detected in most of the subjects with median levels at 325, 457, and 592 pmol/g, respectively. We also found a significantly positive relationship between logged levels of E2-2,3-Q-4-S-Alb and those of E2-3,4-Q-2-S-Alb (r = 0.537, p<0.001). We noticed that logged levels of 1,2-NPQ-Alb are positively and significantly associated with increasing logged levels of E2-3,4-Q-2-S-Alb (r = 0.539, p<0.001). This evidence suggests that environmental exposure to PAHs may enhance the production of reactive quinone species of endogenous estrogen in human. Overall, we conclude that the methodology developed in this study may be applied to epidemiological study to serve as biomarkers of environmental exposure to PAHs and other modulators of estrogen homeostasis. (This work was supported by the National Science Council, Taiwan, through grant NSC99-2314-B-005-001-MY3)

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 4641. doi:10.1158/1538-7445.AM2011-4641
Abstract 4643: Epstein-Barr virus infection (EBV) and expression of B-cell oncogenic markers in HIV+ diffuse large B-cell lymphoma (DLBCL)
Authors: Chao Chun R. , Abrams Donald , Silverberg Michael J. , Haque Reina , Zha Hongbin D. , Martinez-Maza Otoniel , McGuire Michelle , Chi Margaret , Castor Brandon , Xu Lanfang , Leyden Wendy , Habel Laurel , Said Jonathan
Published: June 2012

Background: Lymphomagenicity of EBV in the setting of HIV infection has been widely accepted. However, the underlying carcinogenic mechanism of EBV is largely unknown and warrants further study. We sought to investigate the hypothesis that EBV infection is associated with expression of specific B-cell oncogenic markers in HIV+ DLBCL.

Methods: HIV+ DLBCL cases diagnosed between 1996-2007 within the Kaiser Permanente California Health Plan were identified. Archived tumor specimens were retrieved and H&E slides were reviewed to identify representative tumor blocks for tissue microarray (TMA) construction. Immunohistochemistry staining was performed on TMA cores to analyze the expression of selected B-cell oncogenic markers in the following categories: (1) mutagenic molecule (that induce mutation/translocation), (2) cell cycle promoter, (3) B-cell activator and (4) anti-apoptotic protein. Percent of DLBCL cells with visible marker staining was scored on a scale from 0-4 (0-9%, 10-24%, 25-49%, 50-74% and ≥75%). EBV infection was determined by in situ hybridization of EBV encoded RNA and was considered positive if ≥10% of the DLBCL cells had detectable EBV. Correlations between EBV and marker expression were examined using Spearman's correlation coefficient.

Results: We identified 194 HIV+ DLBCL cases. Of these, 117 lacked sufficient tissue; another 7 had undetermined EBV status; and 70 were included in the study. Marker expressions are shown in the table:

Conclusion: There was a suggestion that Cyclin E and PKC-β2 were more commonly expressed in EBV+ DLBCL, and that FOXP1, BCL2, and Survivin were more commonly expressed in EBV- DLBCL. However, none of these associations reached statistical significance. These findings provide limited support that the underlying carcinogenic mechanism of EBV involves the mediation of the expression of oncogenic markers examined here. However, our study power was limited, thus requiring confirmation in larger studies.

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 4643. doi:10.1158/1538-7445.AM2011-4643
Abstract 4666: Genetic polymorphisms in the pre-microRNA flanking region and non-small cell lung cancer survival
Authors: Shen Hongbing , Hu Zhibin Zhibin , Chen Jiaping
Published: June 2012

Rationale: Previously, we reported that common variants in pre-miRNA sequences played a role in the prediction of non-small-cell lung cancer (NSCLC) survival.

Objectives: To assess whether variants in the pre-miRNA flanking region can influence the clinical behavior of NSCLC.

Methods: we conducted a two-stage study to examine the impact of a panel of 85 SNPs on the overall survival of 923 NSCLC patients (568 in the screening set and 355 in the validation set) in China.

Measurements and Main Results: Eleven single nucleotide polymorphisms (SNPs) were primarily associated with the NSCLC survival in the univariate analysis. However, in the validation set, only miR-30c-1 rs928508 was consistently a NSCLC survival predictor and the protective role of rs928508 AG/GG genotypes were more pronounced among early stage (stage I/II) patients and patients treated with surgery. The area under curve (AUC) at year 5 was significantly increased from 0.658 to 0.741 after adding the miR-30c-1 rs928508 risk score to the traditional clinical risk score (stage and surgery). Furthermore, in the genotype-phenotype correlation analysis, rs928508 AG/GG genotypes were associated with a significantly decreased expression of precursor and mature miR-30c (P=0.009 and 0.011), but not with that of its primary miRNA. The expression of the host nuclear transcription factor Y (NFYC) gene was correlated with pri-mir-30c-1, but not with rs928508 genotypes, implicating the co-regulation of the transcription of NFYC and pri-mir-30c-1.

Conclusions: Our data indicated, for the first time, that genetic polymorphisms in the pre-miRNA flanking region may be prognostic biomarkers of NSCLC, and rs928508 is such a potential candidate.

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 4666. doi:10.1158/1538-7445.AM2011-4666
Abstract 467: Circulating DNA released from brain tumors in response to conditional cytotoxic/immune stimulatory gene therapy induces activation of TLR9 on pDCs, leading to antitumor immunity
Authors: CANDOLFI MARIANELA , Yagiz Kader , Balasubramanian Karthika , Puntel Mariana , King Gwendalyn D. , Mineharu Yohei , Muhammad AKM G. , Foulad David , Barnett Nicholas , Kroeger Kurt M. , Lowenstein Pedro R. , Castro Maria G.
Published: June 2012

Complexes of DNA and proinflammatory proteins are found in serum during autoimmune responses and activate antigen presenting cells, contributing to autoimmune pathogenesis. Although circulating DNA has been extensively evaluated as a biomarker for cancer progression, its role in the onset of anti-tumor immunity remains elusive. Here we aimed to evaluate the role of circulating DNA in the induction of anti-tumor immunity induced by the combination of immune-stimulant Flt3L and conditionally cytotoxic thymidine kinase (TK), which leads to long-term survival when delivered into intracranial brain tumor models using adenoviral vectors (Ad). Treatment of CNS-1 glioblastoma cells with Ad.TK+GCV led to substantial release of DNA in vitro. Similar results were observed in vivo; intratumoral treatment of established intracranial CNS-1 glioblastomas in rats with Ad-TK/GCV+Ad-Flt3L led to increased levels of circulating DNA in serum when compared to saline-treated tumor-bearing rats. Since our previous results suggest that tumor immunity was dependent on the function of activated pDCs, we aimed to evaluate the hypothesis that circulating tumor DNA induces pDC activation. Using specific inhibitors, such as DNAse, micrococcal DNAse, CpG2088 (an inhibitor of TLR9) and cloroquine (an inhibitor of endocytosis, required for intracellular TLR9 activation), we found that circulating DNA from treated rats induced TLR9-dependent activation of pDCs. Taken together, our results suggest that after treatment of brain tumors with Ad.TK+Ad.Flt3L dying tumor cells release DNA to the general circulation, which mediate antitumor immunity by acting as danger-associated molecular patterns, leading to TLR9 signaling and pDC activation.

Supported by NIH/NINDS grants

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 467. doi:10.1158/1538-7445.AM2011-467
Abstract 4672: Overexpression of NR5A2/LRH1 in pancreatic cancer and possible association with clinical outcome
Authors: Dong Xiaoqun , Li Yanan , Fisher William E. , Chang Ping , Abbruzzese James L. , Li Donghui
Published: June 2012

Pancreatic cancer is the 4th leading cause of cancer deaths in the United States and it has the lowest 5-year survival rate in all tumors. Genome-wide association study (GWAS) has identified a significant association between NR5A2/LRH1 gene variants and risk for pancreatic cancer. LRH1, a direct target of PDX1, governs liver and pancreas differentiation in early embryonic development and controls cholesterol/bile-acid homeostasis and steroidogenesis in adulthood. LRH1 promotes cell proliferation by interacting with β-catenin/Tcf4 signaling and upregulating estrogen metabolic genes. We hypothesize that LRH1 acts as an oncogene in pancreatic cancer.

We measured LRH1 protein expression by immunohistochemistry (IHC) in 129 resected pancreatic tumors and LRH1 mRNA expression by RT-PCR in 15 frozen paired tumor and adjacent normal tissues. We examined the differences in expression levels between tumor and normal tissues using paired t-test. We evaluated the correlation of protein or mRNA expression levels with overall survival (OS) or tumor characteristics by Cox regression or χ2 test, respectively.

IHC showed both nuclear and cytoplasm staining for LRH1. Tumors had a higher level of LRH1 expression than normal tissue did (Mean ± SD of staining score: 5.46 ± 1.64 vs. 3.73 ± 1.77, respectively, p<0.001). Patients with a higher level of nuclear LRH1 expression had worse survival (HR = 2.41, 95% CI=0.97-6.00, p=0.059) but patients with a higher level of cytoplasmic LRH1 expression had better survival (HR = 0.36, 95% CI = 0.09-1.46, p=0.15). Eight out of 8 tumors (100%) with lower nuclear LRH1 expression (staining score <3) were well or moderately differentiated, while 44 out of 121 (36.4%) of tumors with higher nuclear LRH1 expression (staining score ≥ 3) were poorly differentiated (p=0.03). The LRH1 mRNA expression level was 8-fold higher in tumors than in normal tissues (p<0.001).

The observed association between LRH1 overexpression and worse clinical outcome and more aggressive tumor type supports the hypothesis that LRH1 acts as an oncogene in pancreatic cancer. Whether LRH1 can be a putative therapeutic target for the treatment of pancreatic cancer needs further investigation.

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 4672. doi:10.1158/1538-7445.AM2011-4672