bluuebunny/crossref_metadata_2025 huggingface dataset:
Supplementary Fig. S2 from Pharmacokinetic-pharmacodynamic correlation from mouse to human with pazopanib, a multikinase angiogenesis inhibitor with potent antitumor and antiangiogenic activity
Authors: Kumar Rakesh , Knick Victoria B. , Rudolph Sharon K. , Johnson Jennifer H. , Crosby Renae M. , Crouthamel Ming-Chih , Hopper Teresa M. , Miller Charles G. , Harrington Laura E. , Onori James A. , Mullin Robert J. , Gilmer Tona M. , Truesdale Anne T. , Epperly Andrea H. , Boloor Amogh , Stafford Jeffrey A. , Luttrell Deirdre K. , Cheung Mui
Published: April 2023

Supplementary Fig. S2 from Pharmacokinetic-pharmacodynamic correlation from mouse to human with pazopanib, a multikinase angiogenesis inhibitor with potent antitumor and antiangiogenic activity
Supplementary Fig. S1 from Pharmacokinetic-pharmacodynamic correlation from mouse to human with pazopanib, a multikinase angiogenesis inhibitor with potent antitumor and antiangiogenic activity
Authors: Kumar Rakesh , Knick Victoria B. , Rudolph Sharon K. , Johnson Jennifer H. , Crosby Renae M. , Crouthamel Ming-Chih , Hopper Teresa M. , Miller Charles G. , Harrington Laura E. , Onori James A. , Mullin Robert J. , Gilmer Tona M. , Truesdale Anne T. , Epperly Andrea H. , Boloor Amogh , Stafford Jeffrey A. , Luttrell Deirdre K. , Cheung Mui
Published: April 2023

Supplementary Fig. S1 from Pharmacokinetic-pharmacodynamic correlation from mouse to human with pazopanib, a multikinase angiogenesis inhibitor with potent antitumor and antiangiogenic activity
Supplementary Materials from Paclitaxel-resistant cells have a mutation in the paclitaxel-binding region of β-tubulin (Asp26Glu) and less stable microtubules
Authors: Hari Malathi , Loganzo Frank , Annable Tami , Tan Xingzhi , Musto Sylvia , Morilla Daniel B. , Nettles James H. , Snyder James P. , Greenberger Lee M.
Published: April 2023

Supplementary Methods, Table S1, and Figure S1
Supplementary Fig. S2 from Potentiation of antileukemic therapies by Smac mimetic, LBW242: effects on mutant FLT3-expressing cells
Authors: Weisberg Ellen , Kung Andrew L. , Wright Renee D. , Moreno Daisy , Catley Laurie , Ray Arghya , Zawel Leigh , Tran Mary , Cools Jan , Gilliland Gary , Mitsiades Constantine , McMillin Douglas W. , Jiang Jingrui , Hall-Meyers Elizabeth , Griffin James D.
Published: April 2023

Supplementary Fig. S2 from Potentiation of antileukemic therapies by Smac mimetic, LBW242: effects on mutant FLT3-expressing cells
Data from Humanized ADEPT comprised of an engineered human purine nucleoside phosphorylase and a tumor targeting peptide for treatment of cancer
Authors: Afshar Sepideh , Asai Tsuneaki , Morrison Sherie L.
Published: April 2023

Abstract
Immunogenicity caused by the use of nonhuman enzymes in antibody-directed enzyme prodrug therapy has limited its clinical application. To overcome this problem, we have developed a mutant human purine nucleoside phosphorylase, which, unlike the wild-type enzyme, accepts (deoxy)adenosine-based prodrugs as substrates. Among the different mutants of human purine nucleoside phosphorylase tested, a double mutant with amino acid substitutions E201Q:N243D (hDM) is the most efficient in cleaving (deoxy)adenosine-based prodrugs. Although hDM is capable of using multiple prodrugs as substrates, it is most effective at cleaving 2-fluoro-2′-deoxyadenosine to a cytotoxic drug. To target hDM to the tumor site, the enzyme was fused to an anti-HER-2/neu peptide mimetic (AHNP). Treatment of HER-2/neu-expressing tumor cells with hDM-AHNP results in cellular localization of enzyme activity. As a consequence, harmless prodrug is converted to a cytotoxic drug in the vicinity of the tumor cells, resulting in tumor cell apoptosis. Unlike the nonhuman enzymes, the hDM should have minimal immunogenicity when used in antibody-directed enzyme prodrug therapy, thus providing a novel promising therapeutic agent for the treatment of tumors. [Mol Cancer Ther 2009;8(1):185–93]
Data from Chemosensitizing effects of sphingosine kinase-1 inhibition in prostate cancer cell and animal models
Authors: Pchejetski Dimitri , Doumerc Nicolas , Golzio Muriel , Naymark Maria , Teissié Justin , Kohama Takafumi , Waxman Jonathan , Malavaud Bernard , Cuvillier Olivier
Published: April 2023

Abstract
We have previously reported that, in prostate cancer, inhibition of the oncogenic sphingosine kinase-1/sphingosine 1-phosphate (SphK1/S1P) pathway is a key element in chemotherapy-induced apoptosis. Here, we show that selective pharmacologic inhibition of SphK1 triggers apoptosis in LNCaP and PC-3 prostate cancer cells, an effect that is reversed by SphK1 enforced expression. More importantly, we show for the first time that the up-regulation of the SphK1/S1P pathway plays a crucial role in the resistance of prostate cancer cells to chemotherapy. Importantly, pharmacologic SphK1 inhibition with the B-5354c compound sensitizes LNCaP and PC-3 cells to docetaxel and camptothecin, respectively. In vivo, camptothecin and B-5354c alone display a limited effect on tumor growth in PC-3 cells, whereas in combination there is a synergy of effect on tumor size with a significant increase in the ceramide to S1P sphingolipid ratio. To conclude, our study highlights the notion that drugs specifically designed to inhibit SphK1 could provide a means of enhancing the effects of conventional treatment through the prosurvival antiapoptotic SphK1/S1P pathway. [Mol Cancer Ther 2008;7(7):1836–45]
Data from Mithramycin SK modulates polyploidy and cell death in colon carcinoma cells
Authors: Bataller Marc , Méndez Carmen , Salas José A. , Portugal José
Published: April 2023

Abstract
During a normal cell cycle, polyploidy and aneuploidy can be prevented by several checkpoints, which are mainly p53 dependent. Here, we show that treatment of HCT-116 (p53+/+) colon carcinoma cells with the novel antitumor antibiotic mithramycin SK (MSK) results in polyploidization and mitotic catastrophe, which occurs after a transient halt in G1 phase followed by the overtaking of the G2-M checkpoint when treated cells are incubated in a fresh drug-free medium. Cells reentering aberrant mitosis mainly died by necrosis, although active caspase-3 was observed. Our results indicate that a decrease in p53 RNA and protein levels, together with concomitant changes in the expression of other proteins such as p21WAF1, were involved in MSK-induced polyploidy. Furthermore, the effects of MSK on HCT-116 (p53+/+) cells cannot be attributed exclusively to the down-regulation of p53 by MSK, because these effects differed from those observed in MSK-treated HCT-116 (p53−/−) cells. The p53−/− cells died mainly from G2-M through early p53-independent apoptosis, which appeared to be mediated by caspase-2, although secondary necrosis was also observed. [Mol Cancer Ther 2008;7(9):2988–97]
Data from Identification and characterization of small-molecule inhibitors of hepsin
Authors: Chevillet John R. , Park Gemma J. , Bedalov Antonio , Simon Julian A. , Vasioukhin Valeri I.
Published: April 2023

Abstract
Hepsin is a type II transmembrane serine protease overexpressed in the majority of human prostate cancers. We recently demonstrated that hepsin promotes prostate cancer progression and metastasis and thus represents a potential therapeutic target. Here we report the identification of novel small-molecule inhibitors of hepsin catalytic activity. We utilized purified human hepsin for high-throughput screening of established drug and chemical diversity libraries and identified sixteen inhibitory compounds with IC50 values against hepsin ranging from 0.23-2.31 μM and relative selectivity of up to 86-fold or greater. Two compounds are orally administered drugs established for human use. Four compounds attenuated hepsin-dependent pericellular serine protease activity in a dose dependent manner with limited or no cytotoxicity to a range of cell types. These compounds may be used as leads to develop even more potent and specific inhibitors of hepsin to prevent prostate cancer progression and metastasis. [Mol Cancer Ther 2008;7(10):3343–51]
Data from Polymeric nanogels containing the triphosphate form of cytotoxic nucleoside analogues show antitumor activity against breast and colorectal cancer cell lines
Authors: Galmarini Carlos M. , Warren Galya , Kohli Ekta , Zeman Arin , Mitin Anton , Vinogradov Serguei V.
Published: April 2023

Abstract
The therapeutic efficiency of anticancer nucleoside analogues (NA) strongly depends on their intracellular accumulation and conversion into 5′-triphosphates. Because active NATP cannot be directly administrated due to instability, we present here a strategy of nanoencapsulation of these active drugs for efficient delivery to tumors. Stable lyophilized formulations of 5′-triphosphates of cytarabine (araCTP), gemcitabine (dFdCTP), and floxuridine (FdUTP) encapsulated in biodegradable PEG-cl-PEI or F127-cl-PEI nanogel networks (NGC and NGM, respectively) were prepared by a self-assembly procedure. Cellular penetration, in vitro cytotoxicity, and drug-induced cell cycle perturbations of these nanoformulations were analyzed in breast and colorectal cancer cell lines. Cellular accumulation and NATP release from nanogel was studied by confocal microscopy and direct high-performance liquid chromatography analysis of cellular lysates. Antiproliferative effect of dFdCTP nanoformulations was evaluated in human breast carcinoma MCF7 xenograft animal model. Nanoencapsulated araCTP, dFdCTP, and FdUTP showed similar to NA cytotoxicity and cell cycle perturbations. Nanogels without drugs showed very low cytotoxicity, although NGM was more toxic than NGC. Treatment by NATP nanoformulations induced fast increase of free intracellular drug concentration. In human breast carcinoma MCF7 xenograft animal model, i.v. dFdCTP-nanogel was equally effective in inhibiting tumor growth at four times lower administered drug dose compared with free gemcitabine. Active triphosphates of NA encapsulated in nanogels exhibit similar cytotoxicity and cell cycle perturbations in vitro and faster cell accumulation and equal tumor growth-inhibitory activity in vivo at much lower dose compared with parental drugs, illustrating their therapeutic potential for cancer chemotherapy. [Mol Cancer Ther 2008;7(10):3373–80]
Data from Role of repair protein Rad51 in regulating the response to gefitinib in human non-small cell lung cancer cells
Authors: Ko Jen-Chung , Hong Jhao-Hao , Wang Lyu-Han , Cheng Chau-Ming , Ciou Shih-Ci , Lin Szu-Ting , Jheng Ming-Yan , Lin Yun-Wei
Published: April 2023

Abstract
Gefitinib (Iressa, ZD1839) is a selective epidermal growth factor receptor tyrosine kinase inhibitor that can block growth factor-mediated cell proliferation and extracellular signal-regulated kinases 1/2 (ERK1/2) activation. High-level Rad51 expression has been reported in chemoresistant or radioresistant carcinomas. In this study, we examined the role of Rad51 in regulating the response to gefitinib among different human lung cancer cell lines. The H520 line (human squamous cell carcinoma) was less sensitive to gefitinib compared with the H1650 (human adenocarcinoma) or A549 (human bronchioloalveolar carcinoma) lines. In H1650 and A549 cells but not in H520 cells, gefitinib decreased cellular levels of phospho-ERK1/2 and Rad51 protein and message levels. Moreover, gefitinib decreased Rad51 protein levels by enhancing Rad51 protein instability through 26S proteasome-mediated degradation. Inhibition of endogenous Rad51 levels by si-Rad51 RNA transfection significantly enhanced gefitinib-induced cytotoxicity. In contrast, transfection with constitutively active MKK1 vector could restore both Rad51 protein levels and cell survival inhibited by gefitinib. The MKK1/2-ERK1/2 signaling pathway constitutes the upstream signaling for maintaining Rad51 message and protein levels. Rad51 protein can protect lung cancer cells from cytotoxic effects induced by gefitinib. Suppression of Rad51 may be a novel lung cancer therapeutic modality to overcome drug resistance to gefitinib. [Mol Cancer Ther 2008;7(11):3632–41]
Data from Silencing of Tubulin Binding Cofactor C Modifies Microtubule Dynamics and Cell Cycle Distribution and Enhances Sensitivity to Gemcitabine in Breast Cancer Cells
Authors: Hage-Sleiman Rouba , Herveau Stéphanie , Matera Eva-Laure , Laurier Jean-Fabien , Dumontet Charles
Published: April 2023

Abstract
Tubulin binding cofactor C (TBCC) is essential for the proper folding of α- and β-tubulins into microtubule polymerizable heterodimers. Because microtubules are considered major targets in the treatment of breast cancer, we investigated the influence of TBCC silencing on tubulin pools, microtubule dynamics, and cell cycle distribution of breast cancer cells by developing a variant MCF7 cells with reduced content of TBCC (MC−). MC− cells displayed decreased content in nonpolymerizable tubulins and increased content of polymerizable/microtubule tubulins when compared with control MP6 cells. Microtubules in MC− cells showed stronger dynamics than those of MP6 cells. MC− cells proliferated faster than MP6 cells and showed an altered cell cycle distribution, with a higher percentage in S-phase of the cell cycle. Consequently, MC− cells presented higher sensitivity to the S-phase–targeting agent gemcitabine than MP6 cells in vitro. Although the complete duration of mitosis was shorter in MC− cells and their microtubule dynamics was enhanced, the percentage of cells in G2-M phase was not altered nor was there any difference in sensitivity to antimicrotubule-targeting agents when compared with MP6 cells. Xenografts derived from TBCC variants displayed significantly enhanced tumor growth in vivo and increased sensitivity to gemcitabine in comparison to controls. These results are the first to suggest that proteins involved in the proper folding of cytoskeletal components may have an important influence on the cell cycle distribution, proliferation, and chemosensitivity of tumor cells. Mol Cancer Ther; 10(2); 303–12. ©2011 AACR.
Data from ENMD-2076 Is an Orally Active Kinase Inhibitor with Antiangiogenic and Antiproliferative Mechanisms of Action
Authors: Fletcher Graham C. , Brokx Richard D. , Denny Trisha A. , Hembrough Todd A. , Plum Stacy M. , Fogler William E. , Sidor Carolyn F. , Bray Mark R.
Published: April 2023

Abstract
ENMD-2076 is a novel orally active, small molecule kinase inhibitor with a mechanism of action involving several pathways key to tumor growth and survival: angiogenesis, proliferation, and the cell cycle. ENMD-2076 has selective activity against the mitotic kinase Aurora A, as well as kinases involved in angiogenesis (VEGFRs, FGFRs). ENMD-2076 inhibited the growth in vitro of a wide range of human solid tumor and hematopoietic cancer cell lines with IC50 values ranging from 0.025 to 0.7 μmol/L. ENMD-2076 was also shown to induce regression or complete inhibition of tumor growth in vivo at well-tolerated doses in tumor xenograft models derived from breast, colon, melanoma, leukemia, and multiple myeloma cell lines. Pharmacodynamic experiments in vivo showed that in addition to inhibiting Aurora A, single doses of ENMD-2076 had sustained inhibitory effects on the activation of Flt3 as well as the angiogenic tyrosine kinases, VEGFR2/KDR and FGFR1 and 2. ENMD-2076 was shown to prevent the formation of new blood vessels and regress formed vessels in vivo at doses equivalent to those that gave substantial activity in tumor xenograft models. These results indicate that ENMD-2076 is a well-tolerated, orally active multitarget kinase inhibitor with a unique antiangiogenic/antiproliferative profile and provides strong preclinical support for use as a therapeutic for human cancers. Several phase 1 studies involving ENMD-2076 have been recently completed, and the compound is currently being evaluated in a phase 2 clinical trial in patients with platinum-resistant ovarian cancer. Mol Cancer Ther; 10(1); 126–37. ©2010 AACR.
Data from The G-rich promoter and G-rich coding sequence of basic fibroblast growth factor are the targets of thalidomide in glioma
Authors: Mei Szu-Chieh , Wu Rong-Tsun
Published: April 2023

Abstract
Thalidomide is considered to be a potent antiangiogenic and immunomodulatory drug for cancer therapy. Earlier clinical studies have found that patients responding to this drug often had high plasma levels of basic fibroblast growth factor (bFGF). This cytokine is a proangiogenic factor overexpressed in many tumors and is also a regulator of limb development; hence, it might be a target of thalidomide. Using U-87 MG cell lines, we found that thalidomide, especially when encapsulated in a liposome, down-regulated the transcription and translation of the FGF-2 gene by interacting with G-rich regions present in the promoter and the internal ribosome entry site of its transcript at concentrations much lower than therapeutic serum concentrations. Thalidomide treatment also dramatically suppressed the anchorage-independent growth of U-87 MG and other glioma cells by over a thousand fold without affecting its anchorage-dependent growth, which may be accomplished by knocking down endogenous bFGF expression in these cells. Accordingly, the addition of recombinant bFGF partially restored the anchorage-independent growth of these cells. Our data suggest that by targeting the G-rich regions of bFGF, thalidomide (at 0.1 μg/mL) can reduce cellular bFGF levels and affect tumor anchorage-independent growth, the hallmark of tumorigenicity. Our results are promising for future clinical investigations using low doses of thalidomide. [Mol Cancer Ther 2008;7(8):2405–14]
Data from Biological characterization of AT7519, a small-molecule inhibitor of cyclin-dependent kinases, in human tumor cell lines
Authors: Squires Matthew S. , Feltell Ruth E. , Wallis Nicola G. , Lewis E. Jonathan , Smith Donna-Michelle , Cross David M. , Lyons John F. , Thompson Neil T.
Published: April 2023

Abstract
Cyclin-dependent kinases (CDK), and their regulatory cyclin partners, play a central role in eukaryotic cell growth, division, and death. This key role in cell cycle progression, as well as their deregulation in several human cancers, makes them attractive therapeutic targets in oncology. A series of CDK inhibitors was developed using Astex's fragment-based medicinal chemistry approach, linked to high-throughput X-ray crystallography. A compound from this series, designated AT7519, is currently in early-phase clinical development. We describe here the biological characterization of AT7519, a potent inhibitor of several CDK family members. AT7519 showed potent antiproliferative activity (40-940 nmol/L) in a panel of human tumor cell lines, and the mechanism of action was shown here to be consistent with the inhibition of CDK1 and CDK2 in solid tumor cell lines. AT7519 caused cell cycle arrest followed by apoptosis in human tumor cells and inhibited tumor growth in human tumor xenograft models. Tumor regression was observed following twice daily dosing of AT7519 in the HCT116 and HT29 colon cancer xenograft models. We show that these biological effects are linked to inhibition of CDKs in vivo and that AT7519 induces tumor cell apoptosis in these xenograft models. AT7519 has an attractive biological profile for development as a clinical candidate, and the tolerability and efficacy in animal models compare favorably with other CDK inhibitors in clinical development. Studies described here formed the biological rationale for investigating the potential therapeutic benefit of AT7519 in cancer patients. [Mol Cancer Ther 2009;8(2):324–32]
Data from Urokinase Plasminogen Activator Receptor and/or Matrix Metalloproteinase-9 Inhibition Induces Apoptosis Signaling through Lipid Rafts in Glioblastoma Xenograft Cells
Authors: Chetty Chandramu , Lakka Sajani S. , Bhoopathi Praveen , Gondi Christopher S. , Veeravalli Krishna Kumar , Fassett Daniel , Klopfenstein Jeffrey D. , Dinh Dzung H. , Gujrati Meena , Rao Jasti S.
Published: April 2023

Abstract
Small interfering RNA (siRNA)-mediated transcriptional knockdown of urokinase plasminogen activator receptor (uPAR) and matrix metalloproteinase-9 (MMP-9), alone or in combination, inhibits uPAR and/or MMP-9 expression and induces apoptosis in the human glioblastoma xenograft cell lines 4910 and 5310. siRNA against uPAR (pU-Si), MMP-9 (pM-Si), or both (pUM-Si) induced apoptosis and was associated with the cleavage of caspase-8, caspase-3, and poly(ADP-ribose) polymerase. Furthermore, protein levels of the Fas receptor (APO-1/CD-95) were increased following transcriptional inactivation of uPAR and/or MMP-9. In addition, Fas siRNA against the Fas death receptor blocked apoptosis induced by pU-Si, pM-Si, or pUM-Si, thereby indicating the role for Fas signaling in pU-Si–, pM-Si–, or pUM-Si–mediated apoptotic cell death of human glioma xenograft cells. Thus, transcriptional inactivation of uPAR and/or MMP-9 enhanced localization of Fas death receptor, Fas-associated death domain-containing protein, and procaspase-8 into lipid rafts. Additionally, disruption of lipid rafts with methyl β cyclodextrin prevented Fas clustering and pU-Si–, pM-Si–, or pUM-Si–induced apoptosis, which is indicative of coclustering of Fas death receptor into lipid rafts in the glioblastoma xenograft cell lines 4910 and 5310. These data indicate the crucial role of the clusters of apoptotic signaling molecule-enriched rafts in programmed cell death, acting as concentrators of death receptors and downstream signaling molecules, and as the linchpin from which a potent death signal is launched in uPAR- and/or MMP-9–downregulated cells. Mol Cancer Ther; 9(9); 2605–17. ©2010 AACR.
Data from Inhibition of focal adhesion kinase as a potential therapeutic strategy for imatinib-resistant gastrointestinal stromal tumor
Authors: Sakurama Kazufumi , Noma Kazuhiro , Takaoka Munenori , Tomono Yasuko , Watanabe Nobuyuki , Hatakeyama Shinji , Ohmori Osamu , Hirota Seiichi , Motoki Takayuki , Shirakawa Yasuhiro , Yamatsuji Tomoki , Haisa Minoru , Matsuoka Junji , Tanaka Noriaki , Naomoto Yoshio
Published: April 2023

Abstract
Focal adhesion kinase (FAK) is often up-regulated in a variety of malignancies, including gastrointestinal stromal tumor (GIST), and its overexpression seems to be associated with tumor progressiveness and poor prognosis. GIST is well known to have a mutation to c-KIT; thus, a specific c-KIT inhibitor (imatinib) is recognized as the first-line chemotherapy for GIST, although a certain type of c-KIT mutation reveals a resistance to imatinib due to as yet uncertain molecular mechanisms. To assess the c-KIT mutation-related variation of cellular responses to imatinib, murine lymphocyte-derived Ba/F3 cells, which are stably transduced with different types of c-KIT mutation, were treated with either imatinib or a FAK inhibitor (TAE226), and their antitumor effects were determined in vitro and in vivo. A mutation at exon 11 (KITdel559-560) displayed a high sensitivity to imatinib, whereas that at exon 17 (KIT820Tyr) showed a significant resistance to imatinib in vitro and in vivo. KIT820Tyr cells appeared to maintain the activities of FAK and AKT under the imatinib treatment, suggesting that FAK might play a role in cell survival in imatinib-resistant cells. When FAK activity in those cells was inhibited by TAE226, cell growth was equally suppressed and the cells underwent apoptosis regardless of the c-KIT mutation types. Oral administration of TAE226 significantly diminished tumor growth in nude mice bearing KIT820Tyr xenografts. In summary, c-KIT mutation at exon 17 displayed a resistance to imatinib with maintained activations of FAK and subsequent survival signals. Targeting FAK could be a potential therapeutic strategy for imatinib-resistant GISTs. [Mol Cancer Ther 2009;8(1):127–34]
Data from Microtubule Dynamics, Mitotic Arrest, and Apoptosis: Drug-Induced Differential Effects of βIII-Tubulin
Authors: Gan Pei Pei , McCarroll Joshua A. , Po'uha Sela T. , Kamath Kathy , Jordan Mary Ann , Kavallaris Maria
Published: April 2023

Abstract
Overexpression of βIII-tubulin is associated with resistance to tubulin-binding agents (TBA) in a range of tumor types. We previously showed that small interfering RNA silencing of βIII-tubulin expression hypersensitized non–small cell lung cancer cells to TBAs. To determine whether βIII-tubulin mediates its effect on drug-induced mitotic arrest and cell death by differentially regulating microtubule behavior, the effects of βIII-tubulin knockdown on microtubule dynamics were analyzed in H460 non–small cell lung cancer cells stably expressing green fluorescent protein-βI-tubulin. Interphase cells were examined at three vincristine and paclitaxel concentrations that (a) inhibited cell proliferation, (b) induced 5% to 10% mitotic arrest, and (c) induced 30% to 40% mitotic arrest. In the absence of either drug, βIII-tubulin knockdown caused no significant change in microtubule dynamic instability. At 2 nmol/L vincristine (IC50), overall microtubule dynamicity was significantly suppressed in βIII-tubulin knockdowns (−31.2%) compared with controls (−6.5%). Similar results were obtained with paclitaxel, suggesting that knockdown of βIII-tubulin induces hypersensitivity by enhancing stabilization of microtubule dynamics at low drug concentrations. At higher drug concentrations (≥40 nmol/L vincristine; ≥20 nmol/L paclitaxel), βIII-tubulin knockdown resulted in significantly reduced suppressive effects on microtubule dynamicity with little or no further increase in mitotic arrest, compared with control cells. Importantly, apoptosis was markedly increased by βIII-tubulin knockdown independent of further suppression of microtubule dynamics and mitotic arrest. These results show that βIII-tubulin knockdown enhances the effectiveness of TBAs through two mechanisms: suppression of microtubule dynamics at low drug concentrations and a mitosis-independent mechanism of cell death at higher drug concentrations. Mol Cancer Ther; 9(5); 1339–48. ©2010 AACR.
Data from Identification of phosphotyrosine mimetic inhibitors of human tyrosyl-DNA phosphodiesterase I by a novel AlphaScreen high-throughput assay
Authors: Marchand Christophe , Lea Wendy A. , Jadhav Ajit , Dexheimer Thomas S. , Austin Christopher P. , Inglese James , Pommier Yves , Simeonov Anton
Published: April 2023

Abstract
Tyrosyl-DNA phosphodiesterase I (Tdp1) resolves topoisomerase I (Top1)-DNA adducts accumulated from natural DNA damage as well as from the action of certain anticancer drugs. Tdp1 catalyzes the hydrolysis of the phosphodiester bond between the catalytic tyrosine residue of topoisomerase I and the DNA 3′-phosphate. Only a limited number of weak inhibitors have been reported for Tdp1, and there is an unmet need to identify novel chemotypes through screening of chemical libraries. Herein, we present an easily configured, highly miniaturized, and robust Tdp1 assay using the AlphaScreen technology. Uninhibited enzyme reaction is associated with low signal, whereas inhibition leads to a gain of signal, making the present assay format especially attractive for automated large-collection high-throughput screening. We report the identification and initial characterization of four previously unreported inhibitors of Tdp1. Among them, suramin, NF449, and methyl-3,4-dephostatin are phosphotyrosine mimetics that may act as Tdp1 substrate decoys. We also report a novel biochemical assay using the SCAN1 Tdp1 mutant to study the mechanism of action of methyl-3,4-dephostatin. [Mol Cancer Ther 2009;8(1):240–8]
Data from Administration of PLK-1 small interfering RNA with atelocollagen prevents the growth of liver metastases of lung cancer
Authors: Kawata Eri , Ashihara Eishi , Kimura Shinya , Takenaka Kazumasa , Sato Kiyoshi , Tanaka Ruriko , Yokota Asumi , Kamitsuji Yuri , Takeuchi Miki , Kuroda Junya , Tanaka Fumihiro , Yoshikawa Toshikazu , Maekawa Taira
Published: April 2023

Abstract
Liver metastasis is one of the most important prognostic factors in lung cancer patients. However, current therapies are not sufficient. RNA interference provides us a powerful and promising approach for treating human diseases including cancers. Herein, we investigated the in vitro effects of PLK-1 small interfering RNA (siRNA) on human lung cancer cell lines and the in vivo usage of PLK-1 siRNA with atelocollagen as a drug delivery system in a murine liver metastasis model of lung cancer. PLK-1 was overexpressed in cell lines and in cancerous tissues from lung cancer patients. PLK-1 siRNA treatment inhibited growth and induced apoptosis in a concentration-dependent manner. To verify in vivo efficacy, we confirmed that atelocollagen was a useful drug delivery system in our model of implanted luciferase-labeled A549LUC cells by detecting reduced bioluminescence after an i.v. injection of luciferase GL3 siRNA/atelocollagen. PLK-1 siRNA/atelocollagen was also successfully transfected into cells and inhibited the progression of metastases. This study shows the efficacy of i.v. administration of PLK-1 siRNA/atelocollagen for liver metastases of lung cancer. We believe siRNA therapy will be a powerful and promising strategy against advanced lung cancer. [Mol Cancer Ther 2008;7(9):2904–12]
Data from The discovery and mechanism of action of novel tumor-selective and apoptosis-inducing 3,5-diaryl-1,2,4-oxadiazole series using a chemical genetics approach
Authors: Jessen Katayoun A. , English Nicole M. , Yu Wang Jean , Maliartchouk Sergei , Archer Shannon P. , Qiu Ling , Brand Regina , Kuemmerle Jared , Zhang Han-Zhong , Gehlsen Kurt , Drewe John , Tseng Ben , Cai Sui Xiong , Kasibhatla Shailaja
Published: April 2023

Abstract
A novel series of 3,5-diaryl-oxadiazoles was identified as apoptosis-inducing agents through our cell and chemical genetics–based screening assay for compounds that induce apoptosis using a chemical genetics approach. Several analogues from this series including MX-74420 and MX-126374 were further characterized. MX-126374, a lead compound from this series, was shown to induce apoptosis and inhibit cell growth selectively in tumor cells. To elucidate the mechanism(s) by which this class of compounds alters the signal transduction pathway that ultimately leads to apoptosis, expression profiling using the Affymetrix Gene Chip array technology was done along with other molecular and biochemical analyses. Interestingly, we have identified several key genes (cyclin D1, transforming growth factor-β1, p21, and insulin-like growth factor-BP3) that are altered in the presence of this compound, leading to characterization of the pathway for activation of apoptosis. MX-126374 also showed significant inhibition of tumor growth as a single agent and in combination with paclitaxel in murine tumor models. Using photoaffinity labeling, tail-interacting protein 47, an insulin-like growth factor-II receptor binding protein, was identified as the molecular target. Further studies indicated that down-regulation of tail-interacting protein 47 in cancer cells by small interfering RNA shows a similar pathway profile as compound treatment. These data suggest that 3,5-diaryl-oxadiazoles may be a new class of anticancer drugs that are tumor-selective and further support the discovery of novel drugs and drug targets using chemical genetic approaches.
Data from Identification of novel small-molecule compounds that inhibit the proproliferative Krüppel-like factor 5 in colorectal cancer cells by high-throughput screening
Authors: Bialkowska Agnieszka B. , Du Yuhong , Fu Haian , Yang Vincent W.
Published: April 2023

Abstract
Colorectal cancer is one of the leading causes of cancer mortality and morbidity worldwide. Previous studies indicate that the zinc finger-containing transcription factor Krüppel-like factor 5 (KLF5) positively regulates proliferation of intestinal epithelial cells and colorectal cancer cells. Importantly, inhibition of KLF5 expression in intestinal epithelial cells and colorectal cancer cells by pharmacologic or genetic means reduces their rate of proliferation. To identify additional and novel small molecules that inhibit KLF5 expression and thus colorectal cancer proliferation, we developed a reporter assay using colorectal cancer cell line (DLD-1) that stably expressed a luciferase reporter gene directed by 1,959 bp of the human KLF5 promoter upstream of the ATG start codon and performed a cell-based high-throughput screen with the Library of Pharmacologically Active Compounds that contains 1,280 biologically active compounds. The screen identified 8 potential inhibitors and 6 potential activators of the KLF5 promoter. Three potential inhibitors, wortmannin, AG17, and AG879, were further evaluated by secondary analyses. All three significantly reduced both KLF5 promoter-luciferase activity and protein level in DLD-1 cells in a dose- and time-dependent manner when compared with controls. They also significantly reduced the rate of proliferation of DLD-1 and two other colorectal cancer cell lines, HCT116 and HT29. Our results show the principle of using high-throughput screening to identify small-molecule compounds that modulate KLF5 activity and consequently inhibit colorectal cancer proliferation. [Mol Cancer Ther 2009;8(3):563–70]
Data from Mcl-1 Stability Determines Mitotic Cell Fate of Human Multiple Myeloma Tumor Cells Treated with the Kinesin Spindle Protein Inhibitor ARRY-520
Authors: Tunquist Brian J. , Woessner Richard D. , Walker Duncan H.
Published: April 2023

Abstract
Kinesin spindle protein (KSP/Eg5) inhibitors are novel anticancer agents that have thus far shown only modest activity in the clinic. Understanding how to identify patients who may be most sensitive to treatment is clearly needed to improve the development of these molecules. We studied four multiple myeloma cell lines treated with the KSP inhibitor ARRY-520 to identify factors important for initiating apoptosis while cells are arrested in mitosis. The majority (three of four) of cell lines underwent mitotic arrest, with apoptosis occurring in mitosis within 24 to 30 hours. The remaining line (NCI H929) is temporally refractory to ARRY-520 treatment, undergoing mitotic slippage and subsequently peaking in apoptotic markers after 72 hours of treatment, while most cells are in interphase. Interestingly, loss of the antiapoptotic protein myeloid cell leukemia 1 (Mcl-1) coincided with mitotic cell death. Stabilization of Mcl-1 resulted in a delayed onset of apoptosis, whereas enforced downregulation of Mcl-1 increased cell death in response to KSP inhibition. Thus, variation in responses to KSP inhibition is governed by a balance between survival proteins and spindle checkpoint integrity. Cells relying on short-lived survival proteins during mitosis are more likely to undergo apoptosis in response to KSP inhibition. We propose that patients with hematologic malignancies, which rely on Mcl-1, would therefore be good candidates for treatment with KSP inhibitors. Mol Cancer Ther; 9(7); 2046–56. ©2010 AACR.
Data from A Novel E1B-55kD-Deleted Oncolytic Adenovirus Carrying Mutant KRAS-Regulated hdm2 Transgene Exerts Specific Antitumor Efficacy on Colorectal Cancer Cells
Authors: Liu Chin-Cheng , Liu Jin-Hwang , Wu Suh-Chin , Yen Chueh-Chuan , Chen Wei-Shone , Tsai Ying-Chieh
Published: April 2023

Abstract
E1B-55kD-deleted adenoviruses have been used as conditionally replicative adenoviruses (CRAds) for therapeutic purposes in tumors with loss-of-function p53 mutation. To target cancer cells that harbor activating mutant KRAS (KRASaMut) but spare p53wild normal cells, we constructed and examined by reporter assays a KRASaMut but not p53-responsive promoter, the Δp53REP2 promoter. The Δp53REP2 promoter, derived from human double minute 2 (hdm2) P2 promoter with its p53 response elements being deleted, was used to regulate the expression of the hdm2 transgene in a novel E1B-55kD-deleted CRAd, the Ad-KRhdm2. The Ad-KRhdm2 selectively replicated in and exerted cytopathic effects on KRASaMut colorectal cancer cell lines (HCT116, LoVo, LS174T, LS123, and SW620), regardless of their p53 gene statuses, by forming plaques and exhibiting cytopathic effect in cultured cells. Ad-KRhdm2, like other E1B-55kD-deleted adenoviruses, also exerted selective cytopathic effects on tumor cells with loss-of-function p53 mutant. The multiplicities of infection of Ad-KRhdm2 required to decrease 50% viability of KRASaMut tumor cells cultured for 7 days were 440 to 3,400 times less than those of MRC5 normal fibroblasts and KRASwild/p53wild RKO tumor cells. Intratumoral injection of Ad-KRhdm2 vectors exhibited specific lytic activities in nude mouse xenografts of KRASaMut cell lines (LoVo, SW620, and LS174T) but not in xenografts of RKO cells. Transduction of KRASaMut/p53wild HCT116, LoVo, and LS174T cells by Ad-KRhdm2 significantly increased Hdm2 expression, decreased p53 level, and abolished the p53-transactivating p21Cip1 promoter activity. Ad-KRhdm2 has shown its therapeutic potential in KRASaMut cancer cells and warrants further clinical trials. Mol Cancer Ther; 9(2); 450–60
Data from Human rhomboid family-1 gene silencing causes apoptosis or autophagy to epithelial cancer cells and inhibits xenograft tumor growth
Authors: Yan Zhenwen , Zou Huafei , Tian Fang , Grandis Jennifer R. , Mixson A. James , Lu Patrick Y. , Li Lu-Yuan
Published: April 2023

Abstract
The rhomboid family of genes carry out a wide range of important functions in a variety of organisms. Little is known, however, about the function of the human rhomboid family-1 gene (RHBDF1). We show here that RHBDF1 function is essential to epithelial cancer cell growth. RHBDF1 mRNA level is significantly elevated in clinical specimens of invasive ductal carcinoma of the breast, and the protein is readily detectable in human breast cancer or head and neck cancer cell lines. Silencing the RHBDF1 gene with short interfering RNA (siRNA) results in apoptosis in breast cancer MDA-MB-435 cells and autophagy in head and neck squamous cell cancer 1483 cells. The treatment also leads to significant down-modulation of activated AKT and extracellular signal-regulated kinase in the cells, suggesting that critically diminished strength of these growth signals may be the key attributes of the induction of cell death. Furthermore, silencing the RHBDF1 gene in MDA-MB-435 or 1483 xenograft tumors on athymic nude mice by using i.v. administered histidine-lysine polymer nanoparticle-encapsulated siRNA results in marked inhibition of tumor growth. Our findings indicate that RHBDF1 has a pivotal role in sustaining growth signals in epithelial cancer cells and thus may serve as a therapeutic target for treating epithelial cancers. [Mol Cancer Ther 2008;7(6):1355–64]
Data from Effects of Src kinase inhibition induced by dasatinib in non–small cell lung cancer cell lines treated with cisplatin
Authors: Ceppi Paolo , Papotti Mauro , Monica Valentina , Iacono Marco Lo , Saviozzi Silvia , Pautasso Marisa , Novello Silvia , Mussino Stefano , Bracco Enrico , Volante Marco , Scagliotti Giorgio V.
Published: April 2023

Abstract
c-Src is a tyrosine kinase involved in tumor proliferation, migration, and angiogenesis and has been shown to modulate the cytotoxicity following cisplatin-induced DNA damages. c-Src is frequently activated in non–small cell lung cancer (NSCLC) tissues and cell lines, but no preclinical data regarding the effects of the novel potent Src inhibitor, dasatinib (BMS-354825), in the modulation of cisplatin resistance are currently available. The present study reports that treatment with dasatinib completely abrogated Src phosphorylation in the majority of the NSCLC cell lines tested (n = 7), with modest effects on cell proliferation and survival. In five cell lines, a higher cytotoxicity was observed delivering cisplatin in combination with dasatinib: the most evident effects were found in the squamous H520 cells due to the effective block of cisplatin-induced Src phosphorylation. Moreover, dasatinib treatment significantly blocked cisplatin-induced transcription of a panel of DNA repair and synthesis genes. In addition, a real-time PCR analysis done on tumor and matched normal lung specimens from 44 surgically resected NSCLC patients showed that Src transcripts are significantly upregulated in 23% of cases. In conclusion, Src-directed therapeutic strategies could interfere with cisplatin resistance, possibly allowing to reduce cisplatin doses, thus improving its efficacy. The data of this study support further clinical studies aimed to evaluate the efficacy of Src-inhibiting agents in combination with cisplatin in the treatment of NSCLC. [Mol Cancer Ther 2009;8(11):3066–74]
Data from Dependence on Phosphoinositide 3-Kinase and RAS-RAF Pathways Drive the Activity of RAF265, a Novel RAF/VEGFR2 Inhibitor, and RAD001 (Everolimus) in Combination
Authors: Mordant Pierre , Loriot Yohann , Leteur Céline , Calderaro Julien , Bourhis Jean , Wislez Marie , Soria Jean-Charles , Deutsch Eric
Published: April 2023

Abstract
Activation of phosphatidylinositol-3-kinase (PI3K)-AKT and Kirsten rat sarcoma viral oncogene homologue (KRAS) can induce cellular immortalization, proliferation, and resistance to anticancer therapeutics such as epidermal growth factor receptor inhibitors or chemotherapy. This study assessed the consequences of inhibiting these two pathways in tumor cells with activation of KRAS, PI3K-AKT, or both. We investigated whether the combination of a novel RAF/vascular endothelial growth factor receptor inhibitor, RAF265, with a mammalian target of rapamycin (mTOR) inhibitor, RAD001 (everolimus), could lead to enhanced antitumoral effects in vitro and in vivo. To address this question, we used cell lines with different status regarding KRAS, PIK3CA, and BRAF mutations, using immunoblotting to evaluate the inhibitors, and MTT and clonogenic assays for effects on cell viability and proliferation. Subcutaneous xenografts were used to assess the activity of the combination in vivo. RAD001 inhibited mTOR downstream signaling in all cell lines, whereas RAF265 inhibited RAF downstream signaling only in BRAF mutant cells. In vitro, addition of RAF265 to RAD001 led to decreased AKT, S6, and Eukaryotic translation initiation factor 4E binding protein 1 phosphorylation in HCT116 cells. In vitro and in vivo, RAD001 addition enhanced the antitumoral effect of RAF265 in HCT116 and H460 cells (both KRAS mut, PIK3CA mut); in contrast, the combination of RAF265 and RAD001 yielded no additional activity in A549 and MDAMB231 cells. The combination of RAF and mTOR inhibitors is effective for enhancing antitumoral effects in cells with deregulation of both RAS-RAF and PI3K, possibly through the cross-inhibition of 4E binding protein 1 and S6 protein. Mol Cancer Ther; 9(2); 358–68
Data from Gambogic acid is an antagonist of antiapoptotic Bcl-2 family proteins
Authors: Zhai Dayong , Jin Chaofang , Shiau Chung-wai , Kitada Shinichi , Satterthwait Arnold C. , Reed John C.
Published: April 2023

Abstract
The natural product gambogic acid (GA) has been reported to have cytotoxic activity against tumor cells in culture and was identified as an active compound in a cell-based high-throughput screening assay for activators of caspases, proteases involved in apoptosis. Using the antiapoptotic Bcl-2 family protein, Bfl-1, as a target for screening of a library of natural products, we identified GA as a competitive inhibitor that displaced BH3 peptides from Bfl-1 in a fluorescence polarization assay. Analysis of competition for BH3 peptide binding revealed that GA inhibits all six human Bcl-2 family proteins to various extents, with Mcl-1 and Bcl-B the most potently inhibited [concentrations required for 50% inhibition (IC50), <1μmol/L]. Competition for BH3 peptide binding was also confirmed using a time-resolved fluorescence resonance energy transfer assay. GA functionally inhibited the antiapoptotic Bcl-2 family proteins as shown by experiments using isolated mitochondria in which recombinant purified Bcl-2 family proteins suppress SMAC release in vitro, showing that GA neutralizes their suppressive effects on mitochondria in a concentration-dependent manner. GA killed tumor cell lines via an apoptotic mechanism, whereas analogues of GA with greatly reduced potency at BH3 peptide displacement showed little or no cytotoxic activity. However, GA retained cytotoxic activity against bax−/−bak−/− cells in which antiapoptotic Bcl-2 family proteins lack a cytoprotective phenotype, implying that GA also has additional targets that contribute to its cytotoxic mechanism. Altogether, the findings suggest that suppression of antiapoptotic Bcl-2 family proteins may be among the cytotoxic mechanisms by which GA kills tumor cells. [Mol Cancer Ther 2008;7(6):1639–46]
Data from Phase II Trial to Evaluate Gemcitabine and Etoposide for Locally Advanced or Metastatic Pancreatic Cancer
Authors: Melnik Marianne K. , Webb Craig P. , Richardson Patrick J. , Luttenton Charles R. , Campbell Alan D. , Monroe Thomas J. , O'Rourke Timothy J. , Yost Kathleen J. , Szczepanek Connie M. , Bassett Michelle R. , Truszkowski Kimberly J. , Stein Phyllis , Van Brocklin Matthew W. , Davis Alan T. , Bedolla Gabriela , Vande Woude George F. , Koo Han-Mo
Published: April 2023

Abstract
Prior studies suggest that tumor cell lines harboring RAS mutations display remarkable sensitivity to gemcitabine and etoposide. In a phase II clinical trial of patients with locally advanced or metastatic pancreatic cancer, we evaluated the response rate to a combination of these drugs. Forty chemo-naïve patients with nonresectable and histologically confirmed pancreatic cancer were accrued. Patients received gemcitabine 1,000 mg/m2 (days 1 and 8) and etoposide 80 mg/m2 (days 8, 9, and 10; 21-day cycle). The primary end point was radiological response rate. Secondary objectives were determination of overall survival, response duration (time to progression), quality of life, toxicity, and CA 19-9 biomarker response. In 35 evaluable patients, 10 exhibited a radiological partial response and 12 had stable disease in response to treatment. Twenty patients exhibited a >20% decrease in CA 19-9 biomarker levels. Median overall survival was 6.7 months for all patients (40) and 7.2 months for evaluable patients (35). Notably, four patients survived for longer than 1 year, with two patients surviving for more than 2 years. Median time to progression for evaluable patients was 3.1 months. The median overall survival for locally advanced patients was 8.8 months and 6.75 months for metastatic patients. One-year survival was 10% for all patients and 11.4% for evaluable patients. Quality of life improved in 12 patients and remained stable in 3 of the evaluable patients. The primary dose-limiting toxicities were hematologic toxicity and fatigue. These results show that the gemcitabine and etoposide combination is generally well-tolerated and exhibits a response rate similar to other published studies. Mol Cancer Ther; 9(8); 2423–9. ©2010 AACR.