bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1267: Metabolic sensor O-GlcNAc Transferase is a novel regulator of prostate cancer invasion and angiogenesis via regulation of FoxM1
Authors: Lynch Thomas P. , RaElle Jackson S. , Shahriari Kristina S. , Ferrer Christina M. , Lazarus Michael , Walker Suzzane , Vosseller Keith , Reginato Mauricio J.
Published: June 2012

Cancer cells universally increase glucose and glutamine consumption, leading to the altered metabolic state known as the Warburg effect. One metabolic pathway highly dependent on glucose and glutamine is the Hexosamine Biosynthetic Pathway (HBP). Increased flux through the HBP leads to increases in the post-translational addition of O-linked-β-N-acetylglucosamine (O-GlcNAc) on a diverse population of nuclear and cytosolic proteins. A number of these target proteins are implicated in cancer, yet the role of O-GlcNAc modifications in cancer remains poorly defined. Here, we show that OGT is overexpressed in prostate cancer tissue compared to normal prostate epithelium and, that OGT protein and O-GlcNAc levels are elevated in prostate carcinoma cell lines compared to non-transformed prostate cells. Decreasing O-GlcNAc levels using OGT-targeted RNAi in the metastatic prostate cancer cell line PC3-ML inhibited growth in three-dimensional (3D) culture, as well as decreased colony formation in soft agar assays. Furthermore, decreasing O-GlcNAc levels was also associated with cell cycle arrest at G1 and increased expression of the CDK inhibitors p27 and p21. However, reducing O-GlcNAc levels in the non-tumorigenic prostate epithelial cell line RWPE-1 had minimal effects on growth in 3D culture. In addition to growth inhibition, reducing O-GlcNAcation in PC3-ML cells was associated with reduced expression of matrix metalloproteinase-2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF), resulting in the inhibition of invasion and angiogenesis. OGT regulation of invasion and angiogenesis was dependent upon regulation of the oncogenic transcription factor FoxM1, as reducing OGT expression led to increased FoxM1 proteasomal degradation. Moreover, overexpression of a FoxM1 degradation-resistant mutant abrogated OGT RNAi inhibition of invasion, MMP levels, as well as angiogenesis and VEGF expression. Finally, the use of novel second-generation small molecule inhibitor of OGT led to the similar reduction in growth, invasion and inhibition of MMPs and VEGF levels. Current experiments are underway to test whether targeting OGT blocks prostate cancer metastasis. Altogether, these data suggest that as prostate cancer cells alter glucose and glutamine levels, O-GlcNAcation serves as nutrient sensitive modification contributing to oncogenesis and suggest that OGT is positioned as a novel target for therapeutic intervention for the treatment of human prostate 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 1267. doi:10.1158/1538-7445.AM2011-1267
Abstract 1269: Identifying Pten-sensitive drug therapy through metabolic phenotype-arrays
Authors: Naguib Adam , Nowak Dawid G. , Chen Muhan , Trotman Lloyd C.
Published: June 2012

The loss or mutation of tumor suppressor genes is a predominant event in the initiation, progression and metastatic development of cancer. PTEN and p53 are frequently inactivated in lethal metastatic prostate cancer, as they provide a critical growth, proliferation and anti-apoptotic advantage to cells in which their activity is diminished. In mouse prostate cancer models, loss of p53 alone in the prostate does not result in noticeable neoplasia. However, subsequent additional deletion of Pten causes lethal prostatic adenocarcinoma within 6 months, illustrating the need to combat the cooperative power of these two genetic lesions. Although inactivation of these tumor suppressor genes has been widely described at the level of their cancer phenotype, it has recently emerged that one understudied route to combat lesions harboring these alterations is to understand and exploit critical underlying changes in their metabolic makeup.

In the present study, we used an array platform to determine the growth phenotype of p53 null Mouse Embryonic Fibroblast (MEFs) under close to 1200 conditions involving different sources of energy, amino acids, hormones, growth factors, chemical ions and responses to chemotherapy agents. with subsequent comparison to the response in p53/Pten double-null MEFs. Our analysis showed that loss of Pten critically altered response, utilization and sensitivity especially to specific hormones, ions and chemotherapy agents. Since this approach revealed Pten-status specific cell sensitivities, we are utilizing this information to establish selective targeting of cells as a precursor to therapeutic intervention in our genetically engineered mouse models of prostate cancer, which harbor the identical tumor suppressor lesions. Collectively, our results establish a rapid screening platform for identification of genotype-specific anti-cancer 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 1269. doi:10.1158/1538-7445.AM2011-1269
Abstract 1294: Metabolism and excretion of eribulin in patients with advanced solid tumors
Authors: Dubbelman Anne-Charlotte , Mergui-Roelvink Marja , Koetz Barbara , Lymboura Margarita , Reyderman Larisa , Lopez-Anaya Arturo , Rosing Hilde , Marchetti Serena , Beijnen Jos H. , Schellens Jan HM
Published: June 2012

This Phase I, open-label, mass-balance study investigated the metabolism and excretion of eribulin, a non-taxane microtubule dynamics inhibitor with a novel mechanism of action, in patients with advanced solid tumors.

A single 14C-eribulin acetate (∼85 μCi) 2 mg dose was given on Day 1 (cycle 1) as a 2-5-min IV bolus injection to 6 patients ≥18 years with advanced solid tumors that progressed after standard therapy or for which no standard therapy existed. Patients received 1.4 mg/m2 unlabeled eribulin mesylate (E7389) on Day 8 (cycle 1), and Days 1 and 8 of each subsequent 21-day cycle. Blood, urine, and fecal samples were collected from Days 1-8 (cycle 1) at specified time points or until sample radioactivity was <1% of the administered dose. Pharmacokinetic parameters were determined from plasma, urine, and fecal concentrations of unmetabolized eribulin and 14C-eribulin- derived material from Day 1 dosing.

Mean plasma eribulin exposure (627 ng.hr/mL) was comparable to that of total radioactivity (568 ng equivalent.hr/mL). Time-matched concentration ratios of eribulin to total radioactivity approached unity in blood and plasma: unchanged parent compound constituted almost all eribulin-derived radioactivity. Few metabolites of eribulin were detected in plasma. Each metabolite represented <0.6% of eribulin indicating there were no major metabolites of eribulin in plasma. Elimination half-lives for eribulin (45.6 hr) and total radioactivity (42.3 hr) were comparable. Eribulin-derived radioactivity excreted in feces was slightly higher (mean 81.5%, range 60.2-101.2%) than that of unchanged eribulin (mean 61.9%, range 42.8-78.5%) indicating that unchanged eribulin was primarily excreted in feces. Renal clearance (0.301 L/hr) was a minor component of total eribulin clearance (3.93 L/hr). Eribulin-derived radioactivity excreted in urine was comparable (mean 8.9%, range 5.4-16.4%) to that of unchanged eribulin (mean 8.1%, range 5.0-15.3%), indicating minimal excretion of metabolite(s) in urine. Total recovery of the radioactive dose was 90.4% in urine and feces.

Overall, no major metabolites of eribulin were detected in plasma. Eribulin is primarily eliminated unchanged in feces, while urine constitutes a minor route of elimination.

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 1294. doi:10.1158/1538-7445.AM2011-1294
Abstract 1298: Effects of carfilzomib (CFZ) on pharmacokinetics of midazolam (MDZ) in subjects with solid tumors
Authors: Jones Suzanne F. , Bendell Johanna C. , Burris Howard A. , Vallone Marcy K. , Wong Alvin F. , Infante Jeffrey R.
Published: June 2012

Introduction: CFZ is a novel, highly selective epoxyketone proteasome inhibitor that has demonstrated durable single-agent antitumor activity in patients (pts) with relapsed or refractory myeloma and solid tumors. PX-171-008 was an open-label, Phase 1b, non-randomized, fixed sequence study to determine the effect of CFZ on the PK of MDZ, a sensitive substrate of human cytochrome P450 3A4.

Methods: During Period 1, pts received a single, 2 mg oral dose of MDZ. In Period 2 the same pts received 27 mg/m2 CFZ IV push on Days 1, 2, 8, 9, 15, and 16 of a single 28-day cycle. Oral MDZ was given immediately following CFZ on Days 1 and 16. The primary endpoint was to evaluate the PK of MDZ in the presence or absence of CFZ. The extent of CYP 3A4/5 interaction was evaluated based on fold-change in AUC for MDZ. ICH Guideline for extent of interaction: Strong = > 5-fold change, Moderate 2-5-fold, Weak = 1.25-2. Safety was evaluated by assessment of adverse events (AEs), clinical laboratory tests, physical exams, vital signs, and an ECG.

Results: 18 pts (12 female, 6 male) were enrolled. Of these, 12 completed and were eligible for full PK analysis, 5 terminated prior to receiving all 6 doses of CFZ and were included only in the day 1 PK analysis, and 1 discontinued prior to receiving any doses of CFZ and was excluded from all PK and safety analysis. All 17 pts included in the PK analysis had significant exposure to CFZ on Day 1. The results suggest that CFZ does not clinically interact with oral MDZ (not even qualifying as a weak inhibitor of CYP3A4). PK parameters are summarized below.

All pts experienced at least 1 AE. The most common were fatigue (52.9%), nausea (52.9%), dyspnea (35.3%), anxiety (23.5%), headache (23.5%), and vomiting (23.5%). AEs were primarily Grade 1/2 in severity and were similar to the safety profile in other CFZ studies.

Conclusions: Administration of CFZ did not result in a clinically significant impact on the PK of MDZ. The observed safety profiles were similar to those previously reported for each drug.

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 1298. doi:10.1158/1538-7445.AM2011-1298
Abstract 13: Chemical genomics identifies MCL1 repressors and resistance mechanism
Authors: Wei Guo , Margolin Adam , Brown Emily , Cucolo Lisa , Stransky Nicolas , Barretina Jordi , Garraway Levi , Beroukhim Rameen
Published: June 2012

Dysregulated apoptotic mechanisms are central to the pathogenesis and maintenance of cancer, and are major barriers to effective treatment. The BCL2 gene family, comprised of both pro- and anti-apoptotic members, controls the intrinsic activation of apoptosis. Amplification of one of the anti-apoptotic members of this pathway, MCL1, constitutes one of the most frequent somatic genetic events in cancer. However, the design of small molecules targeting MCL1 has proven difficult, and the genomic determinants of MCL1 dependence are not well-understood. Furthermore, the contribution of MCL1 regulation in current chemotherapy drug action remains undefined. We therefore developed a chemical genomic approach to identify repressors of MCL1. We measured gene expression levels of all BCL2 family members upon treatment with 2,922 small molecules, including the majority of FDA-approved drugs. We indentified several small molecules inhibiting MCL1 expression, including a few widely used chemotherapy drugs and a natural product triptolide. Those compounds all share similar apoptotic profile when they were tested in panels of cell lines. Genomic profiling indicated that those compounds were global transcriptional repressors (TR). Nevertheless, MCL1 was among the most repressed genes. To further define the contribution of MCL1 repression by those TR compounds, we compared the sensitivity to TRs and MCL1 knockdown. Sensitivity to all TRs correlated with sensitivity to MCL1 knockdown by shRNA; and there is no additive effect of TRs and MCL1 shRNAs. Furthermore, ectopic expression of physiological levels of MCL1 rescued cells from TRs. Triptolide was able to inhibit tumor growth and promote survival in a mouse xenograft model that is sensitive to TR in vitro. Whole genome expression analysis revealed genomic features that correlated with sensitivity to these compounds and to MCL1 shRNAs, and may shed light on biomarker selection when targeting MCL1.

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 13. doi:10.1158/1538-7445.AM2011-13
Abstract 131: Biological effect of miR-210 overexpression on renal carcinoma cells
Authors: Nakada Chisato , Tsukamoto Yoshiyuki , Matsuura Keiko , Nguyen Tung Lam , Hijiya Naoki , Uchida Tomohisa , Sato Fuminori , Mimata Hiromitsu , Seto Masao , Moriyama Masatsugu
Published: June 2012

MiR-210 is significantly upregulated in clear cell renal cell carcinoma (CCC), but the mechanism and biological consequences of miR-210 upregulation are poorly understood. Here, we show that miR-210 is highly expressed in renal carcinoma cell lines and that its expression is clearly correlated with accumulation of hypoxia inducible factor 1α (HIF1α) under normoxia as well as hypoxia, suggesting that miR-210 upregulation in renal carcinoma cells is most likely due to accumulation of HIF1α. To reveal the effects of miR-210 upregulation, the miR-210 precursor was transfected into renal carcinoma cells. After transfection, the cells accumulated at G2/M phase of the cell cycle and their viability was decreased, suggesting that miR-210 overexpression may trigger an event that hinders normal cell division. Immunocytochemistry demonstrated a multipolar spindle accompanied by centrosome amplification in cells overexpressing miR-210. It has been reported that centrosome amplification induces chromosome mis-segregation, finally leading to chromosome instability and aneuploidy. Indeed, the proportion of aneuploid cells (>4n) was increased in miR-210 overexpressed cells. By using the TargetScan and PicTar algorithms, E2F3 was identified as one of the possible targets of miR-210, and was suppressed at the protein level by miR-210. Moreover, the proportion of aneuploid cells was increased in E2F3 siRNA transfected cells. On the basis of these results, we propose that miR-210 upregulation due to HIF1α accumulation may induce aneuploidy via E2F3 downregulation at least in part, and may play a role in tumorigenesis and/or progression of CCC.

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 131. doi:10.1158/1538-7445.AM2011-131
Abstract 1312: Comparative pharmacokinetics of diethylstilbestrol from oral suspension and oral dissolving film (ODF)
Authors: Ako Roland , Tu Shi-Ming , Chow Diana
Published: June 2012

Purpose: To determine the comparative pharmacokinetics of diethylstilbestrol (DES) from oral suspension and oral dissolving film (ODF). DES is a non-steroidal estrogen that has been used in the treatment of both androgen dependent and androgen-independent prostatic cancinoma. However the use of DES to treat advanced prostate cancer was severely limited in the 1980s, because of its thrombogenic side effects common to all estrogens, which are thought to be due to their metabolism in the liver. This metabolism or first pass effect induces the production of proteins associated with the coagulation and fibrinolysis processes, which results in thrombosis and other side effects depending on a patients baseline coagulation-to-fibrinolysis balance. ODF-DES has a potential of bypassing the first pass metabolism minimizing the induction of the coagulation and fibrinolysis proteins.

Methods: The study was performed using 7-week-old male Sprague- Dawyley rats. Under light ketamine and xylazine anesthesia, rats were orally given 1 mg of DES suspension in a 1 ml volume, or topically applied 1 mg of ODF-DES to the buccal cavity. The film was cut into two pieces of 1 cm × 2 cm each and applied to the inner cheeks on each side. Blood samples (250 µl) were collected from the jugular vein up to 30 hr in both cases. DES was extracted from the blood samples using ethyl acetate and analyzed by a validated LC-MS/MS assay.

Results: The pharmacokinetic parameters of DES from oral suspension and ODF-DES were derived using the WinNonlin software. The peak time (tmax) was significantly longer (6.67 ± 2.31 vs 2.16 ± 1.42 hr), and peak concentration (Cmax, 25.82 ± 8.73 vs 6.84 ± 2.45 ng/ml) and systemic exposure (AUC, 213.76 ± 73.09 vs 55.98 ± 3.99 ng h/ml) of ODF-DES were significantly higher with p-values of 0.05, 0.02, and 0.020, respectively than those from oral suspension.

Conclusion: ODF delivery of DES has been demonstrated to improve the bioavailability of DES, by yielding a significantly higher systemic exposure and peak concentration. Further evaluations of ODF-DES are in order to establish the potential merit of the delivery system to reduce the induction of thrombogenic proteins.

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 1312. doi:10.1158/1538-7445.AM2011-1312
Abstract 1320: Estrogen as a modulator of thyroid proliferative disease: Implications for disease etiology and therapy
Authors: Rajoria Shilpi , George Andrea , Shanmugam Arulkumaran , Kamat Ameet , Schantz Stimson P. , Geliebter Jan , Suriano Robert , Tiwari Raj K.
Published: June 2012

Metastasis of cancer is a multifactorial disease and is responsible for over 90% of all cancer related deaths. Thyroid cancer is the most common endocrine related cancer with well differentiated thyroid cancer metastasizing to the nearby lymph nodes in upto 50% of the cases. Interestingly, according to American Thyroid Association (ATA), the incidences of thyroid cancer are four to five times more in women than in men with one in eight women developing thyroid disorder at least once in her lifetime. In this study, we explored the possible etiological contribution of estrogen in thyroid proliferative disease using an in vitro experimental model system. We observed that thyroid cancer cells express functionally active estrogen receptors (ER), ER-α and ER-β. Furthermore, estrogen enhances the metastatic propensity of thyroid cells as evidenced by increased migration, adhesion and invasion, which is reversed by anti-estrogens. These observations were further supported by ER-α down-regulation (siRNA) studies. Western blot and zymography analyses provide direct evidence for this estrogen mediated enhancement of metastasis associated events by enhanced secretion of the proteolytic enzymes, matrix metalloproteinases (MMP), MMP-2 and MMP-9. We also observed that conditioned medium from estrogen treated thyroid cells contains enhanced levels of vascular endothelial growth factor (VEGF) and modulates angiogenesis associated events, such as migration, proliferation and tubulogenesis of endothelial cells. Our studies provide evidence that the higher incidence of thyroid cancer in females is potentially attributed to the presence of a functional ER that participates in cellular processes contributing to enhanced mitogenic, migratory, invasive and angiogenic properties of thyroid cells, which is responsive to anti-estrogens. Our findings formed the basis of an ongoing clinical trial in patients with thyroid proliferative diseases using dietary anti- estrogenic compound, 3, 3’-diindolylmethane (DIM).

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 1320. doi:10.1158/1538-7445.AM2011-1320
Abstract 1326: Systems approach to identifying potential environmental exposures playing a role in ovarian carcinogenesis
Authors: States J. Christopher , Ouyang Ming , Helm C. William
Published: June 2012

Other than an association of a small fraction with inherited mutations in BRCA1 and BRCA2, most cases of ovarian cancer (OvCa) are sporadic with cause unknown. Identifying environmental exposures that may contribute to ovarian carcinogenesis would provide the basis for epidemiological studies to determine other causes of OvCa. Environmental exposures are capable of inducing epigenetic changes that result in changes in gene expression. Most importantly, changes in microRNA expression may cause permanent changes in regulation of gene expression patterns leading to altered cellular phenotypes. These alterations in microRNAs represent dysregulation in the cancer cells and may be a manifestation of environmental exposures. Thus, we hypothesized that circulating microRNAs associated with OvCa are biomarkers of exposure and could be used to identify gene expression changes resulting from environmental exposures. We employed a systems approach utilizing publicly available data for elevated levels of circulating microRNAs associated with OvCa and for altered gene expression in ovarian cancers in conjunction with associations between chemical exposures and gene expression compiled in the Comparative Toxicogenomics Database (CTD) to identify chemicals that may play a role in ovarian carcinogenesis. Intersection of genes with altered expression in ovarian cancer and putative gene targets of microRNAs identified in plasmas of OvCa patients gave a list of candidate genes for chemical interactions. Ingenuity Pathway analyses of these genes show that they participate in pathways involved in cancer and other chronic diseases. This list of genes was submitted to the CTD and a list of chemicals with known interactions with these genes was collected. The list of chemicals interacting with the OvCa specific genes included known carcinogens (arsenic, asbestos, benzo[a]pyrene), co-carcinogens (tetrachlorodibenzodioxin, tetradecanoylphorbol acetate), peroxides, heavy metals (Cu, Zn), epigenotoxicants (hydralizine, valproic acid), inflammation inducers (zymosan, lipopolysaccharide), steroid hormones (estradiol, progesterone, dexamethasone), dietary chemopreventives (indole-3-carbinol, curcumin) and chemotherapeutics (doxorubicin, tamoxifen). While some of these chemicals and pathways have been implicated previously in ovarian carcinogenesis, many have not and their identification will enable the development of targeted epidemiological studies to determine the role of their exposure in inducing or preventing OvCa. This systems approach may be useful to identify environmental exposures contributing to cancer of other organs.

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 1326. doi:10.1158/1538-7445.AM2011-1326
Abstract 1328: Replication inhibition and mutagenicity of 8,5’-cyclopurine-2’-deoxynucleosides in Escherichia coli
Authors: Basu Ashis K. , Jasti Vijay P. , Das Rajat S. , Weerasooriya Savithri
Published: June 2012

8,5’-Cyclopurine-2’-deoxynucleosides are unique tandem DNA lesions formed by oxidation or ionizing radiation, which are repaired only by nucleotide excision repair. They have been suspected to be responsible for neurodegeneration and other diseases. But their replication properties are little studied. In the current work, we have evaluated replication of a pMS2 plasmid containing a single (5's)-8,5’-cyclo-2’-deoxyadenosine (5's-cdA) or (5's)-8,5’-cyclo-2’-deoxyguanosine (5's-cdG) at a preselected site in Escherichia coli. In the wild type E. coli cells, viability of 5's-cdA and 5's-cdG plasmids dropped to approximately 1% and 0.5%, respectively, relative to control. The viability of each was further reduced in pol II-deficient strain, but it was most pronounced in a pol V-deficient strain, where it dropped ten-fold. By contrast, viability increased 4-7-fold in a pol IV-deficient strain. Upon induction of SOS functions, viability increased ten-fold in the wild type strain. Though less pronounced, viability increased in the other strains as well. We conclude that pol V is necessary for translesion synthesis of the cyclopurines and that it may work cooperatively with pol II, which is also needed for bypass. In addition, it appears that although pol IV competes with the other bypass polymerases, it is inefficient in bypassing these lesions. In the absence of SOS, 5's-cdA-to-G mutations occurred at a low frequency, whereas 5's-cdG-to-A events were detected at a much higher frequency. With SOS, 5's-cdA-to-T and 5's-cdG-to-T were also detected. [Supported by NIEHS grant ES-013324]

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 1328. doi:10.1158/1538-7445.AM2011-1328
Abstract 1329: Up-regulation of FOXM1b promotes low doses of arsenite-induced lung carcinogenesis
Authors: Liu Youhong , Sullivan Con , Li Xiong
Published: June 2012

Long-term exposure to low doses of arsenic from environmental sources has been associated with increased incidence of skin, lung, liver, bladder, and prostate cancers. A paradox is that arsenic has not been shown conclusively to be an initiator or a promoter of carcinogenesis in animal models. After E6/E7/hTERT immortalized human airway epithelial cell line NuLi-1 was exposed at 1μM arsenite continuously for 24 weeks, the cells exhibited malignant transformation in the anchorage independent growth assay. Because this cell line is null for p53 and Rb, these data indicated that inactivation of p53 and pRb pathways alone was not sufficient to induce malignant transformation, the addition of long-term exposure of low dose arsenite resulted in malignant transformation. Using a high-throughput method, we detected up-regulated expressions of CDC6, CDC25A and Cyclin D1 (which are critical for cell cycle regulation at G1 and S) when the cells were exposed to 0.1μM arsenite for 24∼72 hours CDC6, CDC25A and Cyclin D1 were expressed over time until cell transformation occurred. Arsenite steadily increased the expression levels of CDC6, CDC25A and Cyclin D1 with time at both transcription and protein levels. Interestingly, the expression of a proliferation-specific transcription factor FOXM1b correlated with increased expression of CDC6, CDC25A and Cyclin D1. FOXM1b is a key regulator of both G1/S and G2/M cell cycle transitions, and mitotic spindle integrity and plays an important role in lung carcinogenesis. Ectopic upregulation of FOXM1b in NuLi-1 cells significantly promoted arsenite-induced malignant transformation; in reverse, knockdown of FOXM1b in the transformed NuLi-1 cells and lung adenocarcinoma cell line A549 significantly decreased malignant transformation. Collectively, the study indicated that upergulation of FoxM1b, of the absence of p53 and pRb in immortalized human airway epithelial cells, promotes low dose arsenite-induced malignant transformation.

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 1329. doi:10.1158/1538-7445.AM2011-1329
Abstract 1340: Examination of in vivo mutagenicity and carcinogenicity in the gpt delta rat with Dammar resin
Authors: Tajiri Masaki , Wei Min , Obo Yumi , Ishii Naomi , Yamano Shotaro , Wanibuchi Hideki
Published: June 2012

Dammar resin is a food additive as a thickening agent. The purposes of this study are to evaluate carcinogenicity and in vivo mutagenicity of Dammar resin in gpt delta rats. 6 week-old male gpt delta rats were divided into 5 groups. Groups 1-3 were treated with five carcinogen (DMBDD) during the first 4 weeks of experiment as follows: diethylnitrosamine (100 mg/kg b.w. i.p.), N-methyl-N-nitrosourea (20mg/kg b.w. i.p.), 1,2-dimethylhydrazine (40 mg/kg b.w. s.c.), 0.05% N-butyl-N-(4-hydroxypropyl) nitrosamine in the drinking water from week 1 to 2, and 0.1% dihydroxybutyl-di-N-propylnitrosamine in the drinking water from week 3 to 4. Groups 4-5 were given vehicle. From experimental week 5, groups 1-3 were treated with Dammar resin in diet at doses of 0, 0.03, and 2% for 13 weeks. Groups 4-5 were treated with Dammar resin in diet at doses of 0, and 2%, respectively. At 18 weeks after starting the experiment, quantitative analysis of glutathione S-transferase placental form (GST-P) positive foci, which are preneoplastic lesions in the rat liver and mutation assays (gpt and Spi- mutation assays) were performed. Both numbers and area of GST-P positive foci were significantly increased in rats administered DMBDD with 2% Dammar resin (group 3) compared to rats administered DMBDD alone (group 1). 0.03% Dammar resin (group 2) had no effects on the development of GST-P positive foci. There were no significant differences in mutant frequencies of gpt and red/gam genes in the livers between rats administered basal diet (group 4) and 2% Dammar resin (group 5). These findings indicated that Dammar resin exerts promotion effect on liver carcinogenesis but lack of in vivo mutagenicity in the livers of gpt delta rats.

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 1340. doi:10.1158/1538-7445.AM2011-1340
Abstract 1342: Effects of the plasticizer metabolite 2 ethyl-1-hexanol on human lymphoblast cells
Authors: Rosado-Berrios Carlos A. , Vélez Christian , Zayas Beatriz
Published: June 2012

The study main objective was to determine the toxicity of 2-ethyl-1-hexanol (EH) and to compare them to its precursor di-ethylhexyl phthalate (DEHP) on the TK6 human lymphoblast cell line. EH is an organic alcohol produced in cells as result of the biotransformation of DEHP. Release of EH from lung cancer cells was also reported recently. Environmental human exposure to the parent DEHP can result through interaction with personal care products, paint lacquer, inks, rubber, dry cleaning and plasticizers such as PVC. Analyzed effects in this study included doses that inhibit cell growth (IC50), damage to the mitochondrial membrane, generation of Reactive Oxygen Species (ROS), and activation of caspase 3 and 7. TK6 cells were cultured on 12.5cm2 flasks with modified RPMI 1640 culture media with 10% FBS, and incubated at 37°C with 5% CO2. IC50 was determined by trypan blue exclusion and mitochondrial membrane permeability applying the Mito PT JC-1 assay from Immunochemistry. For ROS determination the fluorescent dye 2,7-dichlorofluorescein diacetate (DCFH-DA) was applied. For caspases 3 and 7 analysis the Magic RedTM assay from Immunochemistry was applied. Results indicated that IC50s of DEHP and EH on TK6 cells were 234 μM and 75nM respectively. Cells where then exposed to the identified IC50 for 48 hours to measure effects on mitochondria and ROS generation. ROS results indicated that EH generated an average of 96.31 Fluorescence Standard Units (FSU), the negative control Dimethyl Sulphoxide (DMSO) generated 58.22 FSU, the compound used as positive control cis-Di ammine platinum (II) dichloride (Cisplatin) generated 1309.67 FSU and for DEHP the ROS analysis resulted on 793.27 FSU. The level of ROS generated between the parent and this metabolite are not consistent with the degree of toxicity observed. Determination and comparison of the mitochondrial membrane permeabilization as well as Caspases 3 and 7-activation assays of EH are still developing. The preliminary results, however indicates a wide difference in citotoxicity between the parent compound and its metabolite clearly supporting the need for prevention strategies reducing exposure to these controversial plasticizer and therefore potential health effects.

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 1342. doi:10.1158/1538-7445.AM2011-1342
Abstract 1353: Hydrogen sulfide-releasing naproxen inhibits HT-29 human colon cancer cell growth: Modulation of NF-κB
Authors: Nesbitt Diandra E. , Chattopadhyay Mitali , Kodela Ravinder , Boring Daniel , Crowell James A. , Kashfi Khosrow
Published: June 2012

Introduction: Chronic inflammation is widely recognized as an underlying etiological factor in carcinogenesis; there is enough evidence to support the use of non-steroidal anti-inflammatory drugs (NSAIDs) as chemopreventive agents. However, their wide use is precluded due to significant toxicity. Recently, a new class of hydrogen sulfide-releasing NSAIDs have been described in which the parent NSAID is covalently linked to a dithiolethione moiety (5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione) which release hydrogen sulfide. HS-NSAIDs have enhanced safety and efficacy compared to their traditional counterparts. Since NSAIDs are regarded as prototypical chempreventive agents, here we compared naproxen and its hydrogen sulfide-releasing (HS-naproxen) analog using a human colon cancer cell line and also evaluated its effect on NF-κB whose induction is strongly implicated in some cancers.

Methods: HS-naproxen was synthesized and purified at our lab with 1H-NMR verification. Cell line: HT-29 human adenocarcimoma; Cell growth: MTT; Cell cycle phase distribution: Flow cytometry; Apoptosis: subdiploid (sub-G0/G1) peak in DNA content histograms; Proliferation: PCNA; NF-κB: enzyme-linked immunosorbent assay (ELISA). GSH levels: colorimetric method.

Results: HS-naproxen inhibited the growth of HT-29 cells with an IC50 of 72 ± 5 µM whereas for naproxen the IC50 was 2800 ± 190 µM at 24h. HS-naproxen treatment of HT-29 cells at 0.5xIC50, 1xIC50, and 2xIC50 for 24 hrs induced apoptosis (12 ± 1%, 54 ± 3%, 71 ± 3%), inhibited proliferation (PCNA, 71 ± 3%, 49 ± 5%, 26 ± 4%), and caused a G0/G1 cell cycle block. Activation of NF-κB was inhibited as demonstrated by ELISA, at 0.5xIC50, 1xIC50, and 2xIC50 the reduction was 22 ± 3%, 47 ± 2%, and 62 ± 4% respectively. Cellular GSH levels were also reduced dose-dependently by HS-naproxen, suggesting a condition of oxidative stress.

Conclusions: HS-naproxen inhibits HT-29 cell growth and inhibits NF-κB activation. These data suggest that HS-naproxen may be useful as chemopreventive agent against colon cancer and merits further evaluation.

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 1353. doi:10.1158/1538-7445.AM2011-1353
Abstract 1354: New chemical tools for disrupting the Mcl-1/BH3 protein-protein interaction
Authors: Pernazza Daniele , Doi Kenichiro , Lawrence Harshani , Sebti Saïd , Wang Hong-Gang , Lawrence Nicholas
Published: June 2012

Anti-apoptotic members of the Bcl-2 protein family, such as Bcl-2, Bcl-xL and Mcl-1, are among the most effective inhibitors of apoptosis and are frequently upregulated in various types of human cancer. A number of pro-apoptotic proteins share only the BH3 domain with other members of the Bcl-2 family, so called BH3-only proteins, and appear to function essentially as transdominant inhibitors by binding to anti-apoptotic Bcl-2 family proteins and neutralizing their cell-survival activity. The development of small molecules to mimic the BH3 proteins has been an intense area of research. However, to date available Bcl-2 family proteins inhibitors are either pan-inhibitors such as (−)-gossypol (which simultaneously inhibits Bcl-xl/BH3, Bcl-2/BH3 and Mcl-1/BH3 interactions) or are selective for the Bcl-xl/BH3 and Bcl-2/BH3 interactions. Hence a selective Mcl-1/BH3 inhibitor would greatly aid investigating the role of Mcl-1 in cancer and in drug resistance. Our current study is centered on the identification and the synthesis of small molecule selective inhibitors of the Mcl-1/BH3 interaction. To this aim we interrogated the hit-list from inhibitors of the MLSCN screen of the Mcl-1-NOXA interaction [(Emory, AID 1417) TR-FRET screen for Mcl-1-NOXA inhibitors]. Selected compounds were purchased and assessed for activity in a fluorescence polarization and ELISA assay, to reveal the hit HLM050001 (FP IC50 0.8 ± 0.1 µM; ELISA IC50 19.3 ± 2.5 µM). HLM050001binding to Mcl-1 is currently being assessed via co-crystallization and other biophysical techniques. We will report the synthesis and biological evaluation of focused libraries based on the initial hit and designed by modeling and docking to Mcl-1. Structure activity relationship studies around the hit will be disclosed as well as the outcomes of further rounds of chemical design and biological assessment.

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 1354. doi:10.1158/1538-7445.AM2011-1354
Abstract 1356: The Hinge (linker) region of the Hepatocyte Growth Factor (HGF) peptide sequence can act as Hepatocyte Growth Factor/c-Met inhibitor
Authors: Kawas Leen H. , Harding Joseph W. , Yamamoto Brent J. , Wright John W.
Published: June 2012

The central domain interface of the HGF referred to as the hinge region is critical for proper ligand (HGF) dimerization and activation. A peptide sequence representing the hinge region acts as a hinge region mimic, by binding directly to HGF and blocking its dimerization. Ligand dimerization is a critical step in activating the HGF/c-Met signaling pathway. And the interference of this unique structure with HGF dimerization translates into inhibition of HGF-dependent signaling, proliferation, and scattering in multiple cell types at concentrations reaching down into the picomolar range. Not only was the hinge peptide sequence capable of inhibiting HGF in-vitro, but it also showed anti-c-Met/anti-cancer activity in an in-vivo study. As expected, it significantly suppresses pulmonary colonization by B16-F10 murine melanoma cells (in C57BL/6 mice), which are characterized by an overactive HGF/c-Met system. This leads to the conclusion that the hinge peptide sequence exerts its anti-cancerous activity through interfering with the HGF/c-Met system, and that more effective HGF/c-Met antagonists can be designed using the hinge region peptide as the parent compound template. The project was funded by Autzen foundation.

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 1356. doi:10.1158/1538-7445.AM2011-1356
Abstract 1358: Discovery and optimization of potent and selective benzonaphthyridinone analogs as dual mTOR/ATR small molecular inhibitors for treatment of cancer
Authors: Liu Qingsong , Zhou Danny , Shiotani Bunsho , Gray Nathanael S. , Elledge Stephen J. , Zou Lee
Published: June 2012

The Mammalian Target of Rapamycin is a highly conserved Serine/Threonine protein kinase that plays a key role in several fundamental cellular processes such as growth, proliferation and metabolism. As a key node in the PI3K/AKT/mTOR signal pathway, mTOR is currently being actively investigated as a therapeutic target for the treatment of a variety of human cancers. Structurally, mTOR shares high sequence identity in the catalytic domain with other PIKK family kinases including PI3Ks, ATR, ATM, DNA-PK and SMG-1. ATR is an apical kinase in a cell cycle checkpoint pathway that monitors DNA integrity. Upon DNA damage, ATR activation results in cell cycle arrest and the initiation of DNA repair processes. Numerous studies have demonstrated that impairment of ATR function sensitizes cells to death in the presence of chemotherapeutic drugs or ionizing radiation. We hypothesized that a dual mTOR/ATR dual inhibitor might produce a profound apoptotic response in cells with impaired DNA-repair pathways. Starting from the recently developed small molecular ATP competitive mTOR selective inhibitor Torin1, a focused medicinal chemistry exploration of the benzonaphthyridinone structure furnished a library of compounds which was screened in a functional cellular assay for ATR inhibition. Biochemical characterization of select compounds using an immunoprecipitation assays for ATR and mTORC1 kinase activity confirmed that the compounds are dual mTOR/ATR inhibitors. Select compounds were characterized in proliferation assays using p53-deficient HCT-116 cell lines alone and in combination with ionizing radiation.

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 1358. doi:10.1158/1538-7445.AM2011-1358
Abstract 1362: Discovery of a novel structural class of compounds: HLM-030376 and its analogs as potent chymotrypsin-like proteasome inhibitors
Authors: Ge Yiyu , Ozcan Sevil , Kazi Aslamuzzaman , Marsilio Frank , Daniel Kenyon , Brooks Wesley , Guida Wayne , Lawrence Harshani , Sebti Said
Published: June 2012

The ubiquitin-proteasome pathway plays a critical role in the regulated degradation of proteins involved in cell cycle control and tumor growth. Proteasome inhibitors cause selective apoptosis of malignant cells and represent a new class of antineoplastic agents. In 2003 Bortezomib (peptide boronate), a proteasome inhibitor was approved by FDA for treatment of multiple myeloma. Toxicity and tumor cell resistance against Bortezomib demand development of less toxic proteasome inhibitors with broader spectrum of tumor activity. Our aim is to develop non-peptidic small drug-like molecules as proteasome inhibitors. To this end, we have identified through in-house screening efforts HLM-030376 as a small molecule proteasome inhibitor with phenanthridine pharmacophore. HLM-030376 showed in-vitro chymotrypsin like, trypsin like and PGPH inhibitory activities with IC50 values 0.26, 0.19 and 2.07 µM respectively. Extensive synthetic modifications around the HLM-030376 pharmacophore were undertaken to aid the cell activity of this class of compounds. We will describe the synthesis and activity of analogs of HLM-030376 as potent proteasome inhibitors. The analogs of HLM-030376 showed in-vivo CT-L inhibitory activities (IC50 between 0.6-6.0 µM) against MDA-MB 468 breast cancer cell line as well as improved (IC50 between 70-200 nM) in-vitro CT-L inhibitory activities. The detailed in-vitro structure activity relationship (SAR) data of HLM-030376 and analogs will be discussed to understand the structural moieties responsible for proteasome activity. The whole cell activity data of HLM-030376 as well as in-silico docking studies will be presented as potential proteasome inhibitors for further development.

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 1362. doi:10.1158/1538-7445.AM2011-1362
Abstract 1363: Development of novel anticancer agents based on fusarochromanone
Authors: Mahdavian Elahe , Boston Dakota , Grimes Reid , Williams-Hart Tara , Furmanski Brian , Clifford John , Salvatore Brian
Published: June 2012

The primary goal of this research is to develop novel anti-cancer agents based on fusarochromanone (FC101a), a natural mycotoxin with potent anti-angiogenic and direct anti-tumor activity. This research may lead to new cancer chemotherapeutic agents that are more potent and less toxic than conventional chemotherapy. Like most other bioactive natural compounds, the potency of FC101a is compromised in-vivo, suggesting unfavorable bioavailability, distribution, and/or metabolism. Development of FC101a as a chemotherapeutic drug requires the completion of its total synthesis, as well as the synthesis of a series of structural analogs with greater in-vivo potency than the lead compound.

Progress towards both the chemical and biological synthesis of FC101a will be presented. We have employed a new pathway for synthesizing the unique multifunctional four-carbon side chain in the parent compound. We have also been successful in synthesizing the 6-iodo-4-chromanone, a key intermediate that is needed for the coupling reaction with the side-chain. Additionally, we have synthesized two novel acetal analogs of FC101a and will present the rational for choosing these structural analogs for devising structure activity relationships for this series of compounds.

For the biological synthesis, we have obtained a highly fluorescent metabolite from the rice culture of two Fusarium strains (#4482 and #8508) that resembles FC101a, based on TLC analyses. We have also developed an efficient HPLC purification protocol to obtain samples of this compound with high purity. We are currently working to scale up this separation and confirm the structure of this compound through 1H, 13C-NMR as well as high-resolution mass spectrometry analyses.

We will report our preliminary results on the inhibition effects of FC101a on the growth of human aggressive skin cancer carcinoma (SCC) both in-vitro and in-vivo. We have also investigated the mechanism of the biological function of FC101a. We will report our results on the expression levels and phosphorylation states of key proteins involved in cell proliferation signaling pathways, cell sorting profiles, and FACS analyses.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1363. doi:10.1158/1538-7445.AM2011-1363