bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract A119: A proteomics-based approach to identify biomarker profiles of homologous recombination deficiency (HRD) in breast cancer cell lines
Authors: Prime John E. , Unwin Louise , Hunter Jill , Allum Richard , Nickson Janice A. , Rowlinson Rachel , Giavara Sabrina , Lueck Carsten , Lau Alan , O'Connor Mark J. 
Published: June 2012

Abstract
Background: The oral PARP inhibitor olaparib (AZD2281, KU-0059436) has been shown to have single agent clinical activity in tumors from patients with hereditary BRCA mutations (Fong et al., 2009). Pre-clinical studies have also shown sensitivity to PARP inhibition in cells deficient in non-BRCA components of the homologous recombination (HR) DNA repair and signalling pathways. These include proteins such as NBS1, ATM and CHK2 (McCabe et al., 2006), suggesting the broader clinical potential of PARP inhibitors in tumors that are HR deficient (HRD). Thus the ability to identify tumors with HRD will be critical to realising the full potential of this targeted therapy. A proteomics study analysing isogenic breast cancer cell lines in which key HR gene expression had been stably knocked down was performed to identify a broad protein biomarker profile which may contribute to this patient selection strategy. This study also offered the opportunity to identify novel HR associated proteins and a greater understanding of DNA damage responses.
Methods: Nuclear or phospho-protein enriched samples from stable RNAi knockdown breast cancer cell lines (CAL51 and/or MCF7) for 6 key HR genes (BRCA1, BRCA2, ATM, CHEK2, MRE11, NBS1) were analysed using 2 dimensional-difference gel electrophoresis (2D-DIGE) in comparison with parental wild type and/or non specific control cells. The identities of proteins of interest were determined by mass spectrometry. Further analysis of these results was undertaken through bioinformatics approaches utilising the Ingenuity Pathway Analysis (IPA) and GeneGo software tools.
Results: Significant differences in protein abundance were observed in 308 proteins through these proteomic analyses. In depth bioinformatics analysis of these results determined their functional roles, their relationship to the double strand break repair (DSBR) pathways such as HR and non homologous end joining (NHEJ) and DNA damage response (DDR) signalling through network modelling. Where no direct relationship was apparent for these putative HRD associated proteins, their linkage was explored back to the specific HR gene knocked down in the cell line that gave the protein abundance change result. The most consistent cellular functions and pathways associated with the protein changes across the different gene knock downs included cell death, post-translational modification and protein folding.
Conclusions: The abrogation of key genes in the HR pathway leads to wide ranging effects on downstream cellular functions including cell death, post-translational modification and protein folding. These candidate biomarkers of HRD are being developed into a biomarker profile to predict response to olaparib in the clinic.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A119.
Abstract A120: Cellular inhibition of Chk2 kinase and potentiation of camptothecins and radiation by the novel Chk2 inhibitor PV1019
Authors: Jobson Andrew , Lountos George T. , Lorenzi Philip , Connelly John , Tropea Joseph E. , Zoppoli Gabriele , Kondapaka Sudhir , Zhang Guangtao , Caplen Natasha J. , Cardellina John H. , Yoo Stephen S. , Monks Anne , Self Christopher , Waugh David S. , Shoemaker Robert H. , Pommier Yves 
Published: June 2012

Abstract
Chk2 is a checkpoint kinase involved in the ATM pathway, which is activated by genomic instability and DNA damage, leading to either cell death (apoptosis) or cell cycle arrest. Chk2 provides an unexplored therapeutic target against cancer cells. We recently reported NSC 109555 as a novel chemotype Chk2 inhibitor. We have now synthesized a derivative of NSC 109555, PV1019 (NSC 744039), which is a selective sub-micromolar inhibitor of Chk2 in vitro. The co-crystal structure of PV1019 bound in the ATP binding pocket of Chk2 confirmed enzymatic/biochemical observations that PV1019 acts as a competitive inhibitor of Chk2 with respect to ATP. PV1019 was found to inhibit Chk2 in cells. It inhibits Chk2 autophosphorylation (which represents the cellular kinase activation of Chk2), Cdc25C phosphorylation, and HDMX degradation in response to DNA damage. PV1019 also protects normal mouse thymocytes against IR-induced apoptosis, and it shows synergistic antiproliferative activity with topotecan, camptothecin, and radiation in human tumor cell lines. We also show that PV1019 as well as Chk2 siRNA can exert antiproliferative activity themselves in the cancer cells with high Chk2 expression in the NCI60 screen. These data indicate that PV1019 is a potent and selective inhibitor of Chk2 with chemotherapeutic and radiosensitization potential.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A120.
Abstract A141: Synthesis and bioactivity of core-expanded calixarene-based antitumor agents
Authors: Levine Joseph I. , Dings Ruud P.M. , Loren Melissa L. , Hoye Thomas R. , Mayo Kevin H. 
Published: June 2012

Abstract
Anginex, a synthetic 33mer β-sheet-forming peptide, is a potent inhibitor of angiogenesis in vitro and in vivo. Previous studies demonstrate that Anginex, through binding to one of the hydrophobic faces of human galectin-1 (hGal-1), prevents endothelial cell adhesion to the extracellular matrix, induces apoptosis in angiogenically-activated endothelial cells (ECs), and suppresses tumor growth in animal models. Since small molecules have several pharmacologic advantages over therapeutic peptides, we sought to design a small molecule peptidomimetic of anginex. Calix[4]arene was chosen as the basic scaffold to mimic the approximate molecular dimensions, amphipathicity, and cationic topology of Anginex. Chemical modification of the hydrophobic (upper rim) and hydrophilic (lower rim) faces of calix[4]arene resulted in the discovery of a lead compound, 0118, possessing in vitro and in vivo activities similar to that of anginex. These studies reveal that small hydrophobic groups on the upper rim and dimethylaminoethylacetamide (DMAEA) moieties on the lower rim of 0118 are important for its biologic activity.
Until now, structure-activity relationship (SAR) development of calixarene has focused on modifications of its hydrophobic and hydrophilic surfaces. Since the hGal-1-Anginex binding site is a hydrophobic surface, we hypothesize that a larger hydrophobic calixarene surface area will translate into enhanced bioactivity. We have chosen calix[6]arene and tetrathiacalix[4]arene as tools to explore the core-expanded SAR of our lead compound. A calix[6]arene analog of 0118 not only has a larger hydrophobic footprint, but also a greater intra-annular topoisomerization rate which should allow for greater conformational space sampling and, therefore, better inducible fit within its molecular receptor. The tetrathiacalix[4]arene derivative, with its longer C-S bonds (relative to the methylene bonds of calix[4]arene and calix[6]arene), should allow for a hydrophobic footprint larger than the parent 0118 but smaller than that of the calix[6]arene analog. The current studies focus on the synthesis and biologic activity of these 0118 core-expanded derivatives.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A141.
Abstract A144: TriN 2755: Antitumor activity of a new cytotoxic therapeutic of the triazene class
Authors: Bausch Niko , Baltes Steffen , Fiebig Heinz-Herbert , Beckers Thomas , Barth Wolfgang 
Published: June 2012

Abstract
The new cytotoxic anti-neoplastic agent TriN 2755, containing a triazene unit with alkylating properties, has been tested in a variety of patient-derived tumor xenograft models. In these models, TriN 2755 displays potent in vivo anti-tumor activity. In rat, dog and mini pig toxicity studies, TriN 2755 demonstrated a favourable safety profile. Here, we present efficacy data in nude mice of TriN 2755 tested in 15 human tumor xenograft models derived from 9 histologies
Oncotest has developed &gt;200 patient-derived solid tumor models growing s.c. in nude mice. These human tumors were transplanted directly into mice in order to retain the malignant phenotypes as in the patient. Since tumor morphology and sensitivity to anti-cancer drugs is being preserved in these models, results are of high clinical relevance.
A total of 15 xenograft models, among them 4 mammary, 3 melanoma, 2 prostate, 1 colon, pancreas, lung, head and neck, uterine body and bladder tumor models were tested. Tumor-bearing nude mice received TriN 2755 i.p. at doses of 300 to 540mg/kg and different treatment schedules. Treatment started when tumors had grown to diameters of 6–8 mm. Anti-tumor activity was assessed as tumor volume inhibition relative to a vehicle control group (T/C value in %). Tolerability was analysed by recording mortality and body weight loss.
TriN 2755 is a promising anti-cancer agent with an average optimum T/C value of 29.7 % over the 15 experiments representing each tumor model. Optimum T/C values below 50 % were reached in 9/15 tumor models, borderline activity with optimum T/C between 50 and 65 % was observed in 4/15 xenografts with only 2 xenografts being resistant to TriN 2755 (optimum T/C value above 65 %). TriN 2755 had a long lasting therapeutic effect in the melanoma MEXF 462, colon adenocarcinoma CXF 280 and mammary MAXF 401 tumor models. On the last day of treatment, most tumors were either in partial or complete remission. This remission generally lasted until the end of the observation period (days 45, 56 and 42, respectively). TriN 2755 was more effective in these studies than standard-of-care drugs tested in parallel (5- Fluorouracil in colon cancer and Temozolomide in melanomas). Tolerability of TriN 2755 was good with a moderate mortality rate and body weight loss.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A144.
Abstract A147: Novel fluorinated taxane SB-T-12854 active in drug-resistant and sensitive cell lines: Human, pig, rat metabolism, cell transport, and effects on cell cycle
Authors: Gut Ivan , Ehrlichova Marie , Vaclavikova Radka , Ojima Iwao , Simek Petr 
Published: June 2012

Abstract
SB-T-12854 is a novel taxane where fluorine in the molecule could decrease metabolism and increase activity over paclitaxel with efficiency limited by multidrug resistance due to ABCB1 transport, metabolism, and other factors.
Purposes of the study: this study investigated metabolism of SB-T-12854 by human, pig and rat CYP enzymes, cytotoxicity of the drug and isolated metabolites, transport in drug-resistant NCI/ADR-RES cells and sensitive MDA-MB-435, and effects on the cell cycle.
Experimental procedures: Metabolism of SB-T-12854 was studied in human, pig, rat and CYP3A1/2-induced rat microsomes and human cDNA-expressed CYP enzymes in vitro. The metabolites were determined by HPLC and MS analyses.
Human tumor lines MDA-MB-435 and NCI-ADR-RES (NCI, Frederick MD) were kept in standard conditions. Viability was assessed by the MTT assay. Transport of SB-T-12854 by tumor cells was determined by measuring their cellular levels by HPLC. Progress in the cell cycle was determined by FACS.
Summary of new and unpublished data: In human, pig and rat microsomes SB-T-12854 formed the same four products at similar rates, but CYP3A1/2-induced rat microsomes formed 13 metabolites at 16-fold higher rate indicating very high activity of CYP3A, the main human CYP form of varied expression. The cDNA-expressed CYP3A4 formed the same products, but CYP1A2, 1B1, 2A6, 2C9, or 2E1 were inactive. The time course of metabolism and further metabolism of isolated metabolites showed their mutual conversion and identified primary and secondary products. In rat microsomes, Km values for metabolites M5-6 and M9-12 were 14.01 and 6.89 (M), respectively, and Vmax (pmol/min/mg protein) were 70.4 (M5-6) and 370.4 (M9-12).
In MDA-MB-435 cells some metabolites were inactive, but others were considerably more cytotoxic than SB-T-12854 itself in contrast to paclitaxel whose metabolites are less active. SB-T-12854 was 6-fold more cytotoxic than paclitaxel in MDA-MB-435 cells and 30-fold more potent in NCI/ADRRES cells. In both cell lines SB-T-12854 caused G2/M block in the same way as paclitaxel.
Conclusions: SB-T-12854 is metabolized by human, pig and rat CYP3A enzymes to identical and to some markedly more active products in contrast to paclitaxel, which is only inactivated. SB-T-12854 is 30-fold more cytotoxic than paclitaxel in ABCB1 highly expressing NCI/ADR-RES cells, partly because SB-T-12854 is not transported by ABCB1 in contrast to paclitaxel. SB-T-12854 influenced the cell cycle of NCI/ADR-RES and MDA-MB-435 cells in the same way as paclitaxel causing G2/M block, but at substantially lower concentrations. Lack of ABCB1 transport and higher cytotoxicity suggest a potential advantage of this taxane over paclitaxel, which is ineffective against certain tumors, due to high ABCB1 expression.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A147.
Abstract A150: Ciglitazone, PPAR agonist, induces cell death independent of peroxisome proliferator-activated receptor γ (PPARγ) in glioma
Authors: Noh YooHun , Lee Myoung Woo , Kim Dae Seong , Kim Hye Ryung , Chueh Hee Won , Lee Soo Hyun , Yoo Keon Hee , Sung Ki Woong , Jung Hye Lim , Koo Hong Hoe 
Published: June 2012

Abstract
Ciglitazone (CGZ), peroxisome proliferator-activated receptor γ (PPARγ) agonist, is recognized to regulate multiple signal pathways and induce apoptosis in various cancer cells. CGZ induces apoptotic cell death through binding to PPARγ, but interdependence between CGZ and PPARγ is not clear. In this study, over 30 εM CGZ observed significant cytotoxicity in T98G cell line, but not below 25 µM. Cotreatment with 20 µM CGZ and 30 µM GW9662, an antagonist of PPARγ, synergistically induced apoptotic cell death. However, treatment with 30 µM GW9662 not significantly induced cell death and cell-cycle arrest on T98G cells pre-treated with 20 µM CGZ. These results indicate that CGZ may induce cell death independent of PPARγ in T98G cells. In addition, only treatment with 20 µM CGZ in T98G cells induced the activation of Akt. However, cotreatment with 20 µM CGZ and 30 µM GW9662 gradually decreased the activation of Akt. These data indicate that CGZ enhance the antiapoptotic effects by PPARγ binding, while free CGZ on cotreatment with GW9662 PPARγ-independently activates cell death signaling pathway through Akt inactivation. We suggest that combination of CGZ and GW9662 could be therapeutic application for the treatment of glioma.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A150.
Abstract A160: Regulation of resistance of prostate cancer cells to chemotherapy by nanog, a transcription factor for self-renewal of stem cells
Authors: Wang Man-Tzu , Nie Daotai 
Published: June 2012

Abstract
Nanog is a transcription factor usually expressed in embryonic stem cells that plays essential role in the stem cell self-renewal. Expression of Nanog has been detected in a number of cancer cells, especially in those positive for stem/progenitor markers. In the present studies, it was found that there was elevated expression of Nanog in the surviving fractions of tumor cells after chemotherapy. Prospective enrichment of tumor cells with endogenous Nanog expression led to enrichment of tumor cells resistant to Taxol, vinblastine, and doxorubicin, but not camptothecin (CPT). The increased resistance in Nanog expressing cells was attenuated, but not abolished, by inhibitors of p-glycoprotein, the ATP-bind cassette efflux transporter B1 (ABCB1), or by knockdown of ABCB1 via small hairpin RNAs (shRNAs). Expression of ABCB1 was increased in tumor cells enriched with endogenous Nanog expression while knockdown of Nanog reduced the expression of ABCB1 and sensitized tumor cells toward chemotherapeutics. Together, our results suggest that Nanog confers tumor cells with increased resistance to chemotherapy via regulating the expression of ABC transporters.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A160.
Abstract A166: A small molecule inhibitor of Pirin that suppresses tumor cell migration
Authors: Miyazaki Isao , Simizu Siro , Osada Hiroyuki 
Published: June 2012

Abstract
Background: Bcl-3 was originally identified as a putative proto-oncogene which was frequently rearranged in chronic B cell lymphocytic leukemia. Bcl-3 is a member of the I B family which modulates the activities of NF- B/Rel transcription factors. Pirin is known to be bound to Bcl-3, and expression of Pirin was observed in some tumor cell lines, however, the exact roles of Pirin in tumor cells have not been identified.
Materials and Methods: Chemical array screening - Previously, we have developed a nonselective immobilization method that makes possible the introduction of a variety of small molecules to the glass slides. To obtain the small molecules binding to Pirin, we treated the chemical array with cell lysate containing the fusion protein of Pirin-red fluorescent protein. The interaction of Pirin and small molecules was detected by a fluorescence image scanner.
Results: We found the compound, designated compound A, could bind to Pirin by using chemical array screening. We could not detect any interactions of compound A with other proteins we tested. Moreover, we carried out the pull-down assay with compound A-agarose beads, and identified Pirin as compound A-binding protein from the total cell lysate, suggesting the specificity of compound A to Pirin. Recombinant Pirin could bind to recombinant ankyrin repeat domain of Bcl-3, and the interaction was interfered by the treatment with compound A. To clarify the role of Pirin in tumor cells, we treated of the cells with compound A. We found that treatment of the cultured tumor cells with compound A or Pirin-targeted siRNA resulted in suppression of migration, but not cell proliferation.
Conclusion: By use the small molecule and siRNA, it is suggested that Pirin regulates migration of the tumor cells, and the inhibitor of Pirin might be a new chemotherapeutic potential for invasive tumors.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A166.
Abstract A169: Identification of compounds for treatment of solid tumors using spheroid screening
Authors: Fayad Walid , Fryknäs Mårten , Olofsson Maria H. , Larsson Rolf , Linder Stig T. 
Published: June 2012

Abstract
A primary aim of cancer therapy is to irradicate solid tumor masses. Anticancer drugs are nevertheless not systematically developed with this aim in mind - screening and mechanistic studies are usually performed using cells grown under 2-D monolayer conditions. We have developed a procedure to screen for compounds that induce apoptosis of 3-D multicellular tumor spheroids. The chemical properties of spheroid screening hits differed significantly from conventional monolayer screening hits with regard to compound hydrophobicity and polar surface area. The spheroid screen resulted in hits which were more effective than standard chemotherapeutical agents in inducing wide-spread apoptosis of tumor spheroids. Hypotheses regarding the mechanisms of action for the selected compounds were generated using the Connectivity Map (CMAP; a compendium of gene expression signatures from drug treated cell lines). One of the hits in the spheroid screen was the alkaloid thaspine from the South American tree Croton lechleri which we show to be a dual topoisomerase inhibitor. Thaspine is insensitive to overexpression of drug efflux transporters and induces apoptosis of tumor cells in vivo. Counter-screening for compounds that do not induce apoptosis of normal epithelial cells resulted in a limited set of agents, most of which were found to be novel microtubuli inhibitors. The results show that interesting anti-cancer drugs can be identified using spheroid screening.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A169.
Abstract A170: High-content screening for inhibitors of oncogenic transcription by c-Myc
Authors: Collins Tony , Wasylishen Amanda , Penn Linda , Andrews David 
Published: June 2012

Abstract
There is evidence that Myc partners with another molecule called TRRAP to regulate genes required for transformation. Our hypothesis is that blocking the interaction of Myc with TRRAP will selectively kill breast cancer cells. Traditional drug screening approaches to identify compounds that will break apart two interacting proteins have rarely been successful. However, our approach is to screen compounds in live breast cancer cells for those that prevent Myc and TRRAP from binding to each other. Since the cell is constantly replacing Myc, a compound that prevents it from binding TRRAP should kill even established tumors. Importantly, we previously mapped the places on Myc and TRRAP that bind them together and showed they don't involve the parts of the protein involved in other important functions. Therefore, compounds we find that prevent Myc-TRRAP binding should not be toxic to normal cells.
Methods: We have established a new assay in which Myc and TRRAP are expressed as fusion proteins to Cerulean and Citrine fluorescence proteins, respectively. We are developing two different but related assays for the interaction between the two proteins. In one we rely on proximity resulting in complementation between non-fluorescent fragments of the Cerulean fluorescence protein. In this assay heterodimerization results in increased fluorescence. In the other assay proximity results in fluorescence resonance energy transfer (FRET) between the Cerulean and Citrine fluorescence proteins. We detect FRET by fluorescence lifetime imaging (FLIM).
Results: A novel robotic microscope that can automatically perform high speed FLIM and thereby detect Myc-TRRAP binding quickly and accurately has been assembled and tested. Our automated microscope has had an environmental stage for live cell imaging fitted and tested. Both FRET standards and constructs based on the Cerulean-Myc / TRRAP-Citrine pair have been measured to validate the assay. Cell lines are being optimized for use for screening.
Conclusions: High speed FLIM can be used to detect FRET between Cerulean-Myc and TRRAP-Citrine in live cells. Using our automated microscope we can test individually the effect of large numbers of small molecules in live breast cancer cells. This will let us identify compounds that are not only effective but that get into breast cancer cells and are not toxic to normal cells.
Relevance/Impact: To stimulate the development of new drugs effective against a wide spectrum of cancers, we are identifying small drug like molecules that disrupt the function of a particularly potent cell growth gene called Myc, which is often misregulated in breast cancer.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A170.