bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1313: Is serum free RNA available as a predictive biomarker for the response to chemotherapy in patients with lung cancer
Authors: Son Choonhee , Roh Mee-Sook , Um Soo-Jung , Kim Kyu Sik
Published: June 2012

Introduction: It is well-known that cell-free nucleic acids rise in patients with many types of malignancies. Several recent studies have suggested that circulating, cell-free RNA (cRNA) correlates with tumor burden. Furthermore, experimental studies using cancer cell lines have shown that changes in cRNA are predictive of the response to chemotherapy. The objective of this study was to determine whether cRNA can be used as a biomarker for clinical responses to chemotherapy in patients with lung cancer.

Methods: Thirty-two patients with lung cancer (non-small cell lung cancer, n=24; small cell lung cancer, n=8) were divided into 2 groups according to the responses of chemotherapy (response group, n=19; non-response group, n=13). Blood samples were collected before and after two cycles of chemotherapy. Real-time quantitative RT-PCR was used for transcript quantification of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene.

Results: The pre- (Response group: 41.36 ± 1.72 vs. Non-response group: 41.33 ± 1.54, p=0.78) and post- (Response group: 39.92 ± 1.81 vs. Non-response group: 40.41 ± 1.47, p=0.40) chemotherapy cRNA concentration, expressed as the Ct GAPDH level, was not different between the two groups. There was no significant relationship between the change of the cRNA level and clinical response after chemotherapy (p=0.43).

Conclusion: We could not find a correlation between serum cRNA level and clinical responses to chemotherapy in patients with lung cancer. More further investigations are needed to prove cRNA level as a useful predictor of chemotherapy responses in patients with lung cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1313. doi:10.1158/1538-7445.AM2011-1313
Abstract 1314: Estrogen receptor-α is activated in breast ductal epithelial cells by CCN5 in CCN5-conditional tri-transgenic mice
Authors: Majumder Monami , Banerjee Snigdha , Mehta Smita , De Archana , Dhar Kakali , Tawfik Ossama , Larson Melissa A. , Banerjee Sushanta K.
Published: June 2012

Estrogen receptor-alpha (ER-α) is localized in the nuclei of approximately 3-7% of normal resting breast epithelial cells with a higher proportion in lobular cells than in ductal. This number is significantly increased in atypical ductal hyperplasia, ductal carcinoma in situ (DCIS), pure intraductal carcinoma, and intraductal carcinoma with invasive duct carcinoma. Despite having this information for last 15 years, it is still uncertain how ER-α is activated in the nuclei of breast epithelial cells. CCN5/WISP-2, a member of the CCN (Cysteine-rich61/Connective Tissue Growth Factor/Nephroblastoma overexpressed) family of growth factors, is becoming an increasingly important focus in breast cancer research. CCN5/WISP-2 is a two-faced signaling molecule and plays differently in breast carcinogenesis under different micro-environmental setups. Our previous studies have shown that the transcriptional and translational activation of the WISP-2/CCN5 gene is a characteristic of estrogen receptor positive non-invasive breast tumor cell lines. Expression of the WISP-2/CCN5 gene was virtually undetected in non-transformed mammary epithelial cells. Moreover, multiple studies suggest a fine tune between CCN5 signaling and ER-α pathways, but this has not yet been fully elucidated. The main objective of this work was to establish the effect of excessive activation of CCN5 on the ER-α signaling. To do so, we generated a tri-transgenic inducible mouse model that overexpresses CCN5 under the Doxycycline (dox) environment. After the confirmation of the conditional expression of CCN5 in a mammary-specific and dox-dependent manner, morphology as well as the status of ER-α was evaluated. We found that induced expression of CCN5 by Dox in breast epithelial cells significantly increased ER-α expression and activity along with no morphological changes. Collectively, these studies indentify CCN5 as a regulator of ER-α in breast epithelial cells in a tri-transgenic mouse model.

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 1314. doi:10.1158/1538-7445.AM2011-1314
Abstract 1317: Estradiol and progesterone promotes breast tumor growth through induction of AKT/mTOR pathway and inhibition of apoptosis
Authors: Arumugam Arunkumar , Boopalan Thiyagarajan , Delgado Alejandro , Agullo Pamela A. , Parada Jacqueline , Lakshmanaswamy Rajkumar
Published: June 2012

Breast cancer development is accomplished by unbalanced regulation of several signaling pathways. Studies indentifying potential targets for mammary cancer treatment and prevention are vital. Copenhagen strain of rat is a well known animal model which is resistant to carcinogen-induced mammary carcinogenesis. In our laboratory, we were able to induce a very high incidence of mammary cancers in these rats using combination of carcinogen N-methyl-N-nitrosourea (MNU), followed by estradiol and progesterone treatment. We have demonstrated that the resistance to mammary carcinogenesis in these rats is not due to inhibition of initiation but due to reduced hormone promotional environment and we further extend our research to investigate the molecular mechanisms involved behind this hormone-induced promotion. In the present study, we exposed 7 week old female Copenhagen rats to N-methyl-N-nitrosourea (MNU; 50mg/kg body weight). Immediately after MNU treatment the rats were divided into the following groups: 1) Control 2) 17β-estradiol (30mg) 3) progesterone (30mg) and 4) 17β-estradiol (30mg) plus progesterone (30mg). All hormone treatments were administered via individual silastic pellets for a period of 9 months post carcinogen treatment. At the end of the treatment period rat mammary tumors were excised and used for molecular analysis. Quantitative RT-PCR and western blot analysis showed that ovarian hormones treatment triggered the AKT/mTOR pathway along with increased cell cycle progression. Intra cellular MAPK signaling was increased through activation of AKT/PI3K pathway. Hormone administration decreased the levels of caspase-3, caspase-8 and caspase-9. Together, our result indicates that hormone treatment induces mammary tumor growth through activation of AKT/PI3K/mTOR pathways and simultaneously inhibiting apoptosis.

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 1317. doi:10.1158/1538-7445.AM2011-1317
Abstract 1325: Organ, species and sex differences in mutagenesis induced by butyl-hydroxybutyl-N-nitrosamine in big blue transgenic rodents as the basis for the strict organ specificity of this environmental carcinogen metabolite
Authors: He Zhiming , Strasberg-Rieber Zhong-Lin Zhao , Kosinska Wieslawa , Wu Xue-Ru , Guttenplan Joseph B.
Published: June 2012

Although butyl-hydroxybutyl-N-nitrosamine (BBN) is a powerful carcinogen that specifically causes bladder cancer in rodents, the reason for such a high degree of organ specificity is unclear. Mutagenesis induced by BBN in a chromosomally incorporated mutagenesis reporter gene was measured in bladder urothelial cells and smooth muscle cells of mice or rats and compared with mutagenesis in liver, kidney, ureter and forestomach. BBN was administered as a 0.05% solution in water for 2 weeks followed by 4 weeks of water to 6 male and female mice and 4 male rats. All animals were euthanized at 6 weeks. Since mutagenesis in the reporter gene is a surrogate for mutagenesis in general, we hypothesized that mutations also induced in critical growth control genes would contribute to the tumor formation induced by BBN. The mutant fractions in urothelial cells were: 257 +/- 25 mutants / 105 pfu for male mice, 276 +/- 43 for female mice and 54 +/- 6 for rats. In contrast, the mutant fractions in bladder smooth muscle cells were 8-9 fold lower than these values in all animals. In non-bladder tissues such as liver, kidney, ureter and forestomach, the mutant fractions were between 2 and 5 mutants / 105 pfu, a level comparable to the control groups without BBN treatment. Hence mutagenesis correlated extremely well with the organ specificity for cancer induction by BBN. Additionally, mutagenesis level was found to be significantly higher in mice than in rats, consistent with the fact that BBN is a much more potent bladder carcinogen in mice. Finally, no significant difference in mutagenicity of BBN between male and female mice was observed, suggesting that post-initiation processes may be responsible for the gender difference in bladder tumor susceptibility. BBN is a primary metabolite of the environmental carcinogen, dibutylnitrosamine and hence a potential human carcinogen. These results provide molecular explanations to the bewildering organ and species specificity of BBN, and indicate that BBN-induced mutagenesis in the urinary bladder represents a highly appropriate model for initiation of bladder cancer, and combined with other models can help elucidate distinct steps in bladder carcinogenesis. Supported by an NYU Centers of Excellence Seed Grant.

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 1325. doi:10.1158/1538-7445.AM2011-1325
Abstract 133: A microRNA contribution to aberrant Ras activation in gastric cancer
Authors: Wang Xian , Lam Emily , Jin Hongchuan
Published: June 2012

Oncogenic Ras mutations are rare in gastric cancer, indicating that other mechanisms may be responsible for aberrant Ras activation in this type of cancer. Ezrin is critical to Ras activation by remodeling cortical actin cytoskeleton. In this study, we aimed to illustrate the relevance and regulation of ezrin in gastric cancer. Ezrin was upregulated in gastric cancer cells. Ezrin siRNA inhibited Ras activation, cell growth and cell migration. Ezrin overexpression was correlated with a poor outcome of gastric cancer patients (n=150, p<0.01). Cox regression analysis revealed a significant value of ezrin expression in prognosis prediction of gastric cancer (relative risk: 2.37, 95% confidence interval: 1.24-4.56, p<0.01). MiR-204, which was predicted to target ezrin, was downregulated in gastric cancer cells and gastric carcinomas (n=22, p<0.01). MiR-204 inhibited ezrin expression, Ras activation, cell growth and cell migration. Importantly, miR-204 suppressed the expression of luciferase controlled by wild-type but not mutated ezrin 3’-UTR. In conclusion, ezrin is important to Ras activation in gastric cancer. Its upregulation is an independent prognosis prediction factor for gastric cancer. By contributing to ezrin upregulation, miR-204 downregulation represents a novel mechanism for aberrant Ras activation in gastric carcinogenesis.

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 133. doi:10.1158/1538-7445.AM2011-133
Abstract 1336: Nicotine does not promote tumor growth in preclinical mouse models of lung cancer
Authors: Maier Colleen , Hollander M. Christine , Dennis Phillip
Published: June 2012

Nicotine replacement therapy (NRT) is a popular and effective regimen for the cessation of smoking. Expanded use of NRT is controversial based on preclinical studies that show that nicotine activates signaling pathways that promote cellular survival and proliferation. To address the tumor promoting effects of nicotine in mouse models of lung cancer, nicotine was administered in the drinking water and tested in a tobacco carcinogen-driven model (NNK), a genetically engineered model (KRasLA2), and syngeneic mouse xenografts. Pharmacokinetic analysis showed that mice had normal water consumption and achieved an average serum cotinine level of 135 ng/ml, a level comparable to that observed in NRT users. In the NNK model, nicotine was administered after 3 weekly intraperitoneal injections of NNK, and was continued for 12 wk. At the time of sacrifice, nicotine did not increase lung tumor multiplicity or size, and did not activate the Akt/mTOR pathway. In the KRasLA2 model, mice were placed on nicotine at the time of weaning. At 6 wk, there was no effect on tumor multiplicity, size, histology, or tumor biomarkers. Studies assessing the effects of nicotine on overall survival of K-RasLA2 mice are ongoing. Similar negative results were observed with nicotine administration in xenograft studies with isogenic NNK-transformed lung adenocarcinoma cell lines. To assess whether the response to nicotine might be dose-dependent, we assessed activation of the PI3K/Akt/mTOR, MEK/ERK, and JAK/STAT pathways in these cell lines using immunoblotting. Stimulation was only observed at concentrations higher than that observed with NRT. These results suggest nicotine at doses comparable to NRT does not promote lung tumorigenesis.

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 1336. doi:10.1158/1538-7445.AM2011-1336
Abstract 1337: MUC1 facilitates BPDE-induced EGFR activation and malignant transformation in human bronchial epithelial cells
Authors: Xu Xiuling , Bai Lang , Chen Wenshu , Li Zi , Kim Kwang Chul , Belinsky Steven A. , Lin Yong
Published: June 2012

Inflammation has emerged as an important factor for the development of lung cancer. However, the gene targets and pathways that are involved in inflammation-associated lung cancer development have not been clearly elucidated. Cigarette smoke (CS), which causes chronic pulmonary inflammation, is an established risk factor for lung cancer. MUC1 (MUC in human and Muc in animals), a mucin-like glycoprotein expressed on the surface of airway epithelial cells, is inducible during lung inflammation. MUC1 is also overexpressed as a tumor antigen in lung tumors. We found that chronic CS exposure significantly increased Muc1 expression in mouse airway epithelial cells associated with infiltration of inflammatory cells to the lung. The role of MUC1 in lung epithelial cell transformation induced by benzo[a]pyrene diol epoxide (BPDE), the active form of the CS carcinogen benzo(a)pyrene (BaP), was examined in an in vitro cell transformation assay. Knockdown of MUC1 by shRNA significantly reduced the efficacy of BPDE-induced transformation of BEAS-2B, an SV40 large T antigen immortalized human bronchial epithelial cell line. BPDE strongly activated EGFR and Akt in BEAS-2B cells. Akt activation was blocked with an EGFR inhibitor, suggesting that BPDE activates the EGFR/Akt cascade. Blocking this cascade with inhibitors for either EGFR or Akt significantly inhibited BPDE-induced cell transformation, supporting a critical role for EGFR and Akt activation in BPDE-induced cell transformation. Interestingly, the BPDE-induced activation of EGFR and Akt was attenuated when MUC1 expression was knocked down. Suppression of EGFR or Akt significantly increased BPDE's cytotoxicity. Consistently, the MUC1-suppressed BEAS-2B cells were more sensitive to BPDE-induced death. Taken together, these results suggest that MUC1 plays an oncogenic role in the early stages of inflammation-associated lung cancer development, at least partly through mediating carcinogen-induced activation of the EGFR/Akt pathway that potentiates survival in immortalized bronchial epithelial cells.

This work is supported by 1R01ES017328.

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 1337. doi:10.1158/1538-7445.AM2011-1337
Abstract 1341: Insulin directly induces endometrial cell proliferation and carcinogenesis
Authors: Bishop Erin A. , Lightfoot Stan A. , Benbrook Doris M.
Published: June 2012

Introduction: Diabetes and insulin resistance are strong risk factors for type 1 endometrial cancer. The mitogenic actions of insulin are well described, but less is known about the role insulin may play in carcinogenesis. It is unknown if insulin plays direct role in the carcinogensis of endometrial cells or if insulin promotes carcinogenesis through its overall physiological effects. Key pathways within the insulin signaling cascade, such as Ras-MAPK and PI3-K-mTOR, are also involved in the formation and progression of many cancers. The goal of this study was to determine if insulin exerted direct effects on normal endometrial cell proliferation and carcinogenesis.

Methods: The effects of varying doses of insulin on endometrial cells collected from human menstrual blood from healthy volunteers were measured using a standard MTS cytotoxicity assay. These cells were also grown in 3-D organotypic culture for 2 weeks and exposed to a known carcinogen, 7, 12-dimethylbenz[α]anthracene (DMBA), insulin, and the combination of both agents. Effects of insulin were evaluated by histological evaluation and quantified with anchorage independent growth assays.

Results: Insulin increased proliferation of endometrial cells in a dose dependent fashion. In the organotypic model, insulin caused the development of malignant features such as nuclear pleomorphism, hyperchromasia, and mitosis as a single agent and enhanced these malignant features in the DMBA treated cultures. Consistent with these findings, soft agar colony forming assays demonstrated significantly greater numbers of anchorage-independent colonies in cultures treated with insulin plus DMBA in comparison to cultures treated with DMBA alone.

Conclusions: Insulin exerts direct effects on endometrial cells by increasing their proliferation and enhancing their susceptibility to carcinogenesis. Western immunoblotting is now being performed to characterize the effects of insulin on the AKT and MAPK signaling pathways.

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 1341. doi:10.1158/1538-7445.AM2011-1341
Abstract 1346: Discovery of novel MSK1 inhibitors with hybrid virtual screening and structure-based drug design
Authors: Huang Zunnan , Liu Kangdong , Bode Ann M. , Dong Zigang
Published: June 2012

Mitogen- and stress-activated protein kinase 1 (MSK1) is a serine/threonine kinase that is involved in gene transcription regulation and pro-inflammatory cytokine stimulation. MSK1 is an attractive target for the treatment of chronic inflammatory diseases. Currently, no small molecule inhibitor has been identified that specifically targets MSK1 and only H-89 is a known inhibitor. In this study, we performed hybrid virtual screening (HVS) to identify novel small molecule inhibitors that target MSK1. For the screening, we used the active conformation of the C-terminal kinase domain of the dual kinase as the protein template. Computational screening of several well-known compound databases, including the FDA, Natural Product, ZINC all purchasable and PDB ligands databases, revealed 40 potential leads. We tested 11 lead compounds and found 5 that showed substantial in vitro inhibitory activity against MSK1. These results illustrated that our computational screening processes greatly enhanced the success rate of virtual screening. The high-performing HVS protocols were especially successful to retrieve thousands of promising new leads from millions of compounds in conjunction with structure-based drug design and then to further select true hits from the majority of high-scoring decoys.

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 1346. doi:10.1158/1538-7445.AM2011-1346
Abstract 1369: Synthesis of substituted N-[(3-(1H-pyrrol-1yl)methyl]-5,6-dihydropyridin-1(2H)-yl) benzamide/benzene sulfonamide as anticancer agents
Authors: Redda Kinfe Ken , Gangapuram Madhavi , Mochona Bereket , Mateeva Nelly , Ardley Tiffany
Published: June 2012

Cancer has proven to be one of the most intractable human diseases, and as yet no anticancer agents that are highly effective and safe are available. Therefore, synthesis of novel, potent, selective and less toxic anticancer agents remains the most pressing goal of many investigators. Tetrahydropyridine (THP) ring moieties have attracted synthetic interests for being essential structures in many agrochemicals as well as medicinal agents. The anti-inflammatory and anticancer activities of compounds consisting of reduced pyridine ring systems were investigated in our laboratory. The pharmacological activities of the (THP) derivatives depended on the nature of the substituents on the THP ring moiety. In the current investigation, we synthesized many analogs maintaining the N-(3-[(1-H-pyrrol-1-yl)methyl]-5,6-dihydropyridin-1(2H)-yl) benzamide/benzene sulfonamides, at which the phenyl ring was substituted with groups having different electronic, steric and lipophilic properties.

Mesitylene sulfonyl chloride was added with stirring to a solution of ethylacetohydroxymate and triethylamine in dimethylformamide at 0o C. Hydrolysis of this compound with the mixture of p-dioxane-70% perchloric acid and allowing them to react for 45 min gave a white solid of O-mesitylene sulfonyl hydroxylamine (MSH). MSH was used to prepare the N-amino salt since it served as an aminating agent. 3-[(1H-pyrrol-1-yl)methyl]pyridine was reacted with MSH in dichloromethane to produce 3-[(1H-pyrrol-1-yl)methyl]-1-aminopyridinium mesitylenesulfonate, the N-amino salt. Reaction of the amino salt with substituted benzoyl chloride/benzenesulfonyl chloride in anhydrous tetrahydrofuran containing triethylamine gave stable benzoyl/benzene sulfonyl imino ylides. This was followed by reduction with sodium borohydride in absolute ethanol, which furnished the target compounds substituted N-(3-[(1H-pyrrol-1-yl)methyl]-5,6-dihydropyridin-1(2H)-yl) benzamide/benzene sulfonamides. These compounds were evaluated for their cytotoxic effects on MCF-7 estrogen receptor positive breast cancer cells, MDA-MB-231 estrogen receptor negative breast cancer cell line, and Ishikawa cells, using the CellTiter-Glo (CTG) luminescent cell viability assay. N-(3-[(1H-pyrrol-1-yl)methyl]-5,6-dihydropyridin-1(2H)-yl)-4-methoxybenzene- sulfonamide showed the most potent cytotoxicity with an IC50 values of 47, 28, and 44 µM on MCF-7, Ishikawa and MDA-MB-231 cell lines, respectively.

This research was supported by NIH/ RCMI Grant # G12 RR 03020 and Pharmaceutical Research Center NIH/NCRR Grant 1 C06 RR12512-01.

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 1369. doi:10.1158/1538-7445.AM2011-1369
Abstract 1375: A homogeneous high-throughput screening assay for inhibitors of the interaction of MLL-AF4 and AF9 in pediatric leukemia
Authors: Drake Katherine , Napper Andrew D.
Published: June 2012

Chromosomal translocations of the mixed lineage leukemia (MLL) gene occur in 5-10% of pediatric acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), including up to 80% of infant ALL and most treatment-related secondary AML. These MLL rearrangements result in a portion of the MLL protein being fused to one of a number of transcription factors. The prognosis for MLL-rearranged (MLL-R) leukemia is much poorer than for leukemia devoid of MLL fusions; five-year survival of <40% in the case of infant ALL. MLL fusions are potent inducers of leukemia, through recruitment of a protein complex that activates transcription of the HOX (homeobox) oncogene HOXA9, which in turn blocks normal differentiation of progenitor cells and confers a stem cell-like phenotype. The transcription factor AF4 is the most common MLL fusion partner, and MLL-AF4 is associated with a particularly poor prognosis. Direct interaction of MLL-AF4 with the transcription factor AF9 has been shown to be critical to leukemic transformation. Here we describe the development of a homogeneous high-throughput screening (HTS) assay for small-molecule inhibitors of the binding of MLL-AF4 to AF9 and the validation of this assay in pilot HTS. A recent study showed that peptides containing as few as 10 amino acids derived from the AF9 binding site in AF4 bind to AF9 with low nanomolar potency and selectively kill MLL-AF4-containing leukemia cell lines. We have developed an assay that measures binding of an AF4-derived peptide to AF9 protein using AlphaScreen technology, a homogeneous proximity-based method well suited to HTS in 384- and 1536-well plates. Laser excitation of donor beads results in the generation of singlet oxygen, which encounters acceptor beads brought into close proximity by the binding of AF4 peptide to AF9, giving an amplified luminescent signal. Inhibitors are identified by reduction of the luminescent signal. We have validated the assay by demonstrating low nanomolar inhibition by several AF4-derived peptides and by screening a library of 2000 drugs and natural products. The next step is transfer of the assay to the Broad Institute (Cambridge, MA) for HTS against the 400,000-compound NIH library. The ultimate goal is the optimization of lead compounds as novel therapies targeted to pediatric leukemia harboring MLL-AF4, both as stand-alone agents and as synergistic potentiators of existing chemotherapeutic agents.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1375. doi:10.1158/1538-7445.AM2011-1375
Abstract 1380: Engineered toxin bodies with specific activity against EGFR and HER2 expressing cells
Authors: Grant Kari , Higley John , Higgins Jack , Robinson Lee , Null Bill , Zhu Keng , Kim Jason , Cunningham Casey , Poma Eric
Published: June 2012

Antibody approaches that abrogate signaling from the HER2 or EGFR receptors have been proven effective in patients with breast or colorectal cancer, respectively. These antibodies do not have an effect however in colorectal patients with KRAS mutations or breast cancer patients that lack HER2 gene amplification as signal interruption is not sufficient to induce cell death. Here we identify several novel compounds that specifically recognize and kill HER2 and EGFR expressing cells irrespective of receptor signaling. These compounds were identified from a screen of a novel biologic library derived from a de-immunogenized Shiga-like toxin 1 A subunit (SLT1A); SLT1A has no intrinsic binding ability of its own but can drive internalization, retrograde transport to the cytosol, and enzymatic inhibition of ribosome activity. This modified library of engineered toxin bodies (ETBs) was created through the insertion of random amino acids near the C-terminus of the SLT1A scaffold to confer binding ability to SLT1A while preserving the therapeutic PK and ADME profile of the scaffold. HER2 and EGFR specific ETBs have been identified that exhibit potent cell-kill activity.

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 1380. doi:10.1158/1538-7445.AM2011-1380
Abstract 139: MicroRNA-375 and microRNA-221: Potential noncoding RNAs associated with antiproliferative activity of benzyl isothiocyanate in pancreatic cancer
Authors: Basu Aruna , Alder Hansjuerg , Khiyami Amer , Leahy Patrick , Croce Carlo M. , Haldar Subrata
Published: June 2012

Large high-throughput studies in patients with pancreatic cancer revealed that oncogenic miR-221 is commonly upregulated microRNA whereas putative tumor suppressor miR-375 is generally down modulated when compared to adjacent benign pancreatic tissue or normal pancreas. In our laboratory, we observed that deregulated expression of miR-375 and miR-221 (as noted in pancreatic cancer patients) can be recapitulated in PDX1-Cre+; KRasG12D+ pancreatic cancer mouse model. Coherent data obtained from pancreatic cancer patient samples to preneoplastic lesions developed in preclinical mouse model tempted us to postulate that aberrant expression of these miRNAs (−375 and-221) might play significant role for the development of pancreatic cancer. Interestingly, ablation of miR-221 by ectopic expression of antagomir-221 in pancreatic ductal carcinoma cells can significantly exert antiproliferative effect with increased expression of p27kip1, a target of miR-221. To the other end, premiR-375 overexpression diminished cell proliferation with downmodulation of Insulin like growth factor binding protein 5 (IGFBP5) and Caveolin-1 (CAV-1 gene), which are of particular interest because of their potential link with pancreatic cancer cell growth and diagnosis. It is quite intriguing that the levels of both CAV-1 and IGFBP5 expression were elevated when miR-375 expression wanes in KRASG12D driven PanIN lesion in compound mutant mice.

Previous studies in our laboratory demonstrate that benzyl isothiocyanate (BITC), a prototypical member of the isothiocyanate (ITC) family, inhibits proliferation of human pancreatic cancer cells by causing cell cycle arrest and inducing apoptosis. Interestingly, real time qRT-PCR analysis indicates that anticancer agent BITC can diminish oncogenic miR-221 expression and elevate the level of tumor suppressor miR-375 in pancreatic cancer cells. Besides, genetic manipulation studies revealed that enforced silencing of miR-221 or overexpression of miR-375 enhances the antiproliferative effect of BITC in pancreatic ductal carcinoma cells. Next we explored the efficacy of BITC to interfere with the development of mouse PanIN lesions. Results indicate that pancreata of BITC administered compound mutant mice exhibit reduced level of IGFBP5 protein. Histopathological analysis of the extent of PanINs as well as studies on the magnitude of expression of miR-221/miR-375 and other molecular mediators in these pancreata are in progress. Explicitly, our investigation might provide new insight into nonconventional microRNA replacement therapy against pancreatic cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 139. doi:10.1158/1538-7445.AM2011-139
Abstract 1425: Significance of Dickkopf-3 overexpression in the pathogenesis of esophageal adenocarcinoma
Authors: Wang Zhuwen , Thomas Dafydd G. , Orringer Mark B. , Beer David G. , Lin Jules
Published: June 2012

Ninety percent of those diagnosed with esophageal adenocarcinoma ultimately die of their disease highlighting the need for novel therapeutic targets. In order to identify significant molecular changes and potential pathways involved in the progression to esophageal adenocarcinoma, 46 esophagectomy samples, including Barrett's metaplasia, low- and high-grade dysplasia, and esophageal adenocarcinoma, were evaluated using oligonucleotide microarrays. Dickkopf-3 (Dkk-3), a divergent member of the Wnt inhibitor family, was overexpressed in 33.3% (5 of 15) of esophageal adenocarcinoma samples relative to Barrett's metaplasia. The goal of this study was to define the functional significance of Dkk-3 overexpression in esophageal adenocarcinoma. Dkk-3 protein was present at moderate to high levels in 46.8% (29 of 62) of esophageal adenocarcinoma on a tissue microarray. Stable transfection of Dkk-3 into the esophageal adenocarcinoma cell line OE33 lead to significantly increased proliferation 1.6 times vector controls (p < .005). In addition, OE33 cells stably transfected with Dkk-3 showed significantly greater invasion on matrigel assay than native OE33 cells (p < .005). There was no significant decrease in Wnt pathway activation by TOPFLASH assay after transfection of Dkk-3 when compared to OE33 native and vector controls suggesting that overexpression of Dkk-3 acts through a Wnt-independent pathway in esophageal adenocarcinoma. Levels of SMAD4, a key downstream mediator of the TGF-ß pathway, were increased on Western blot after treatment with activin, a member of the TGF-ß superfamily, in OE33 cells stably transfected with Dkk-3 when compared to native and vector controls. These findings suggest that Dkk-3 may be important in mediating proliferation and invasion of esophageal adenocarcinoma through the TGF-β pathway and that Dkk-3 could be a novel therapeutic target in the treatment or prevention of metastatic disease in a cancer with otherwise limited therapeutic options.

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 1425. doi:10.1158/1538-7445.AM2011-1425
Abstract 1429: Apc heterozygosity in the C57BL/6J-Min/+ mouse produces an abnormal exuberant proliferative response in excisional wound healing
Authors: Heit Yvonne , Carothers Adelaide M. , Ross Eric , Rivzi Hira , Orgill Dennis , Bertagnolli Monica M.
Published: June 2012

The Min mouse is a model for intestinal tumor formation. Previously, we showed that the ApcMin allele produces a dominant-negative effect on enterocyte migration and stromal interaction in vivo. Tumorigenesis is driven by features of epithelial-mesenchymal interaction that are observed in wound healing, therefore we hypothesized that the Min phenotype also involved abnormalities in the wounding response program. We performed excisional wound assays on female Min mice (10 or 20-week old), comparing response to that of female age-matched Apc+/+ (WT) mice. The healing kinetics of full thickness dorsum wounds were quantified by digital planimetry. Histological cross sections on post-operative day 7 were used to measure granulation tissue thickness, nascent blood vessel density, and cell proliferation. Western blotting was performed using granulation tissue lysates to compare the expression of adhesion and extracellular matrix proteins, as well as α-smooth muscle actin, a marker for the presence of contractile cells. Immunofluorescent histochemistry was performed to detect the co-expression and quantitation of αSMA+, vimentin+, SM22+, desmin− myofibroblasts at wound edges. Wound closure was faster in Min mice relative to WT mice, 88.85% versus 68.86% (P<0.01). Min mice also showed the strongest induction of granulation tissue formation; the relative granulation tissue thickness in the centre of wounds was 171.15±47.53 and 147.96±16 mm (P<0.01) in Min and WT, respectively. Blood vessel density, measured by counting the number of CD31+ cells/high power field, was increased (40.72 + 22.6) in Min mice when compared to WT (19.03 ± 17.6, P<0.01). The number of proliferating cells in granulation tissue (Ki67+ nuclei/all) in Min mice (63.72±16.83) was greater than in WT (41.58±23.46) (P<0.01). Masson's stain demonstrated that more collagen deposition was present in wounds of Min/+ relative to WT. In conclusion, this study showed that wound healing was accelerated in Min/+ mice relative to WT. Therefore, even before the loss of the WT allele, Apc heterozygosity likely promotes tumor formation because it affects wound-induced invasive, homing, and engraftment responses of the epithelial stroma.

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 1429. doi:10.1158/1538-7445.AM2011-1429
Abstract 1445: The metastasis suppressor NM23-H1 promotes genomic stability through its 3’-5’ exonuclease and nucleoside diphosphate kinase activities following UV irradiation
Authors: Jarrett Stuart G. , Novak Marian , Harris Nathan , Mellon Isabel , Slominski Andrezj , Arnaud-Dabernat Sandrine , Daniel Jean-Yves , Kaetzel David M.
Published: June 2012

NM23-H1 is a metastasis suppressor whose reduced expression is associated with aggressive forms of melanoma, hepatoma, and carcinomas of the breast, stomach and colon. The current study has identified NM23-H1 (termed H1 isoform in human, M1 in mouse) and two of its attendant enzymatic activities, the 3’-5’ exonuclease and nucleoside diphosphate kinase (NDPK), as novel participants in the response to UV-induced DNA damage. Kinetics of repair for total DNA polymerase-blocking lesions and nucleotide excision pathway-mediated repair of 6-4 photoproducts were significantly compromised in different cellular settings of NM23-H1-deficiency. These included the human melanoma cell line WM793 and embryo fibroblasts (MEFs) derived from mouse strains rendered deficient in either NM23-M1 alone or both the M1 and M2 isoforms in tandem. The NDPK activity of NM23-H1 was critical for early repair of both polychromatic UVB/UVA (275-400 nm)- and UVC (254 nm)-induced DNA damage. Elevated rates of spontaneous and UV-induced mutations were observed in WM793 cells and NM23-deficient MEFs. The mutational spectra reflected aberrant repair of 6-4 photoproducts and oxidatively-induced DNA damage, with the 3’-5’ exonuclease being the principal enzymatic activity required to reduce UV-induced mutagenesis. This study has provided the first evidence for an essential role of mammalian NM23 isoforms in maintaining genomic stability. This novel anti-mutator function appears relevant not only to the metastasis suppressor activity of NM23-H1, but also possibly resistance to UV-induced carcinogenesis.

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 1445. doi:10.1158/1538-7445.AM2011-1445
Abstract 1452: The estrogen receptor β and its splice variant estrogen receptor β2 inhibits expression of Runx2, a key regulator of bone metastasis while only estrogen receptor β inhibits proliferation of the prostate cancer cell line PC3
Authors: dey Prasenjit , Gustafsson Jan-Ake , Strom Anders
Published: June 2012

Prostate cancer often metastases to bone in its later stages of tumor progression. We wanted to investigate if estrogen receptor β (ERβ) and/or its splice variant estrogen receptor β2 (ERβ2) are affecting signaling pathways involved in bone metastasis of prostate cancer. ERβ is progressively lost during prostate cancer progression while the splice variant ERβ2 is still expressed in advanced prostate cancer. ERβ2 is a 495 amino acid long splice variant of estrogen receptor ERβ. Using prostate cancer cell line, PC3 stably expressing ERβ or ERβ2, we found that both receptors inhibit migration in wound healing assays and are furthermore, repressing the expression of the bone metastasis regulator Runx2 and its target genes Slug and MMP9. In addition, we found by assaying the TCF/LEF reporter (TopGlow), that ERβ represses β-catenin signaling and it is also known that Runx2's expression is dependent on β-catenin activity. This gives a possible mechanism, by which ERβ represses Runx2 expression, is by inhibiting β-catenin signaling. This opens up a new pathway for the regulation of Runx2 by ERβ. On the other hand, we found that only ERβ and not ERβ2 inhibits proliferation and expression of the proliferation marker Skp2, which we have previously found to be a target gene of ERβ. The lack of antiproliferative activity of ERβ2 suggest that this splice variant could still be expressed in highly proliferative prostate cancer while at the same time inhibiting bone metastasis. In conclusion we found that both ERβ and ERβ2 are good targets for treatment of prostate cancer that might metastasize to the bone.

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 1452. doi:10.1158/1538-7445.AM2011-1452
Abstract 1457: Raf kinase inhibitor protein (RKIP) negatively regulates melanoma differentiation associated gene-9/syntenin-mediated melanoma metastasis
Authors: Das Swadesh K. , Sarkar Devanand , Fisher Paul B.
Published: June 2012

Melanoma differentiation associated gene-9 (mda-9/syntenin) functions as a positive regulator of melanoma progression and metastasis by physically interacting with c-Src and promoting the formation of an active FAK/c-Src signaling complex leading to NFκB and matrix metalloproteinase (MMP) activation. In contrast, Raf Kinase Inhibitor Protein (RKIP), an inhibitor of RAF-mediated activation of mitogen-activated protein/extracellular signal-regulated kinase kinase (MEKK), is strongly downregulated in metastatic melanoma cells suggesting a possible inverse relationship between expression of mda-9/syntenin and RKIP. We have now genetically modulated expression of mda-9/syntenin and RKIP in melanocytes and melanoma cells and evaluated biological consequences using invasion, anchorage-independent growth, Western blotting, immunoprecipitation and in vivo confocal imaging assays. These studies confirm an inverse correlation between mda-9/syntenin and RKIP expression. This reciprocal relationship was also documented in vivo using a chick embryo chorioallantoic membrane (CAM) model, which monitors spontaneous intravasation of cells from the upper to the lower layer by polymerase chain reaction (PCR) amplification of human Alu genomic DNA. Using tissue microarrays and a series of cell lines we confirmed a higher expression of MDA-9/syntenin and absence of RKIP in both malignant melanoma tumor sections and cell lines. We also established through gain-of-function and loss-of-function experiments that mda-9/syntenin transcriptionally downregulates RKIP, providing evidence for crosstalk between these two proteins. Moreover, transient overexpression of RKIP in metastatic melanoma cells overrides mda-9/syntenin-mediated signaling resulting in decreased cell invasion, anchorage-independent growth and spontaneous tumor cell dissemination in the CAM assay. RKIP through its RAF1 binding site (amino acids 77-108) physically interacts with MDA-9/syntenin and this interaction inversely correlates with downregulation of FAK and c-Src phosphorylation, crucial steps necessary for forming a stable FAK/c-Src complex and initiating a signaling cascade leading to an MDA-9/syntenin-mediated metastatic phenotype in melanoma cells. These provocative findings highlight a potential therapeutic role of RKIP in melanoma metastasis through its interaction with MDA-9/syntenin.

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 1457. doi:10.1158/1538-7445.AM2011-1457
Abstract 1468: MTA2 enhances breast cancer metastasis via regulation of the cytoskeleton and rho signaling pathways
Authors: Covington Kyle R. , Brusco Lauren , Beyer Amanda , Cai Weiyan , Corona-Rodriguez Arnoldo , Fuqua Suzanne A.W.
Published: June 2012

Metastasis tumor associated (MTA) 2 is a component of the nucleosome remodeling and histone deacetylation complex and is implicated in regulating gene expression through its associated histone deacetylase activity. We have previously found that MTA2 enhanced the anchorage independent growth phenotype of estrogen receptor alpha (ER)-positive cells, implicating a potential role in metastasis. As MTA2-overexpression in these cells also resulted in an estrogen independent phenotype, we hypothesized that MTA2-overexpression may similarly enhance the aggressiveness of ER-negative cells.

We found that MTA2-overexpressing MDA-MB-231 cells were more invasive through Matrigel, had enhanced soft-agar colony formation activity compared with vector controls, and demonstrated increased migration in wound healing assays. Furthermore, we found that MTA2 overexpression resulted in rapid systemic metastases when grown as orthotopic xenografts, while vector control cells failed to form metastases, in the same time period. Microarray analysis revealed enrichment for genes regulating the cytoskeleton and cell-environment interactions, which was validated using a previously published microarray dataset. We found that the negative regulator of the Rho pathway, Rho GDP dissociation inhibitor alpha (RhoGDI-alpha), was also decreased in expression at the protein level in the MTA2-overexpressing MDA-MB-231 cells. We found that blocking signaling through the Rho pathway by either using a Rho Kinase inhibitor or by overexpressing RhoGDI-alpha significantly reduced the soft-agar colony forming ability of MTA2-overexpressing cells. We examined the effect of MTA2 and RhoGDI-alpha expression in a retrospective breast cancer microarray dataset and found that patients classified as MTA2-high and RhoGDI-alpha-low had significantly earlier recurrence compared with all other patients.

These data indicate that MTA2-overexpression results in an increase in the metastatic potential of breast cancer cells. These results have potential clinical implications as patients who have the MTA2-high/RhoGDI-alpha-low phenotype are at increased risk for early recurrence. In conclusion, our data show that MTA2 and RhoGDI-alpha enhances breast cancer metastasis possibly by promoting invasiveness and anchorage independent growth and survival.

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 1468. doi:10.1158/1538-7445.AM2011-1468