bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from [18F]-FLT Positron Emission Tomography Can Be Used to Image the Response of Sensitive Tumors to PI3-Kinase Inhibition with the Novel Agent GDC-0941
Authors: Cawthorne Christopher , Burrows Natalie , Gieling Roben G. , Morrow Christopher J. , Forster Duncan , Gregory Jamil , Radigois Marc , Smigova Alison , Babur Muhammad , Simpson Kathryn , Hodgkinson Cassandra , Brown Gavin , McMahon Adam , Dive Caroline , Hiscock Duncan , Wilson Ian , Williams Kaye J.
Published: April 2023

Abstract
The phosphoinositide 3-kinase (PI3K) pathway is deregulated in a range of cancers, and several targeted inhibitors are entering the clinic. This study aimed to investigate whether the positron emission tomography tracer 3′-deoxy-3′-[18F]fluorothymidine ([18F]-FLT) is suitable to mark the effect of the novel PI3K inhibitor GDC-0941, which has entered phase II clinical trial. CBA nude mice bearing U87 glioma and HCT116 colorectal xenografts were imaged at baseline with [18F]-FLT and at acute (18 hours) and chronic (186 hours) time points after twice-daily administration of GDC-0941 (50 mg/kg) or vehicle. Tumor uptake normalized to blood pool was calculated, and tissue was analyzed at sacrifice for PI3K pathway inhibition and thymidine kinase (TK1) expression. Uptake of [18F]-FLT was also assessed in tumors inducibly overexpressing a dominant-negative form of the PI3K p85 subunit p85α, as well as HCT116 liver metastases after GDC-0941 therapy. GDC-0941 treatment induced tumor stasis in U87 xenografts, whereas inhibition of HCT116 tumors was more variable. Tumor uptake of [18F]-FLT was significantly reduced following GDC-0941 dosing in responsive tumors at the acute time point and correlated with pharmacodynamic markers of PI3K signaling inhibition and significant reduction in TK1 expression in U87, but not HCT116, tumors. Reduction of PI3K signaling via expression of Δp85α significantly reduced tumor growth and [18F]-FLT uptake, as did treatment of HCT116 liver metastases with GDC-0941. These results indicate that [18F]-FLT is a strong candidate for the noninvasive measurement of GDC-0941 action. Mol Cancer Ther; 12(5); 819–28. ©2013 AACR.
Data from A Heterodimeric Fc-Based Bispecific Antibody Simultaneously Targeting VEGFR-2 and Met Exhibits Potent Antitumor Activity
Authors: Choi Hye-Ji , Kim Ye-Jin , Lee Sangho , Kim Yong-Sung
Published: April 2023

Abstract
Heterodimeric Fc designed by engineering the CH3 homodimeric interface of immunoglobulin G1 serves as an attractive scaffold for the generation of bispecific antibodies (bsAb) due to the favorable properties of the Fc region. In this study, we describe a heterodimeric Fc generated by substituting the conserved electrostatic interactions at the CH3 core interface with asymmetric hydrophobic interactions and introducing asymmetric, long-range electrostatic interactions at the rim of the CH3 interface. Coexpression of Fc proteins carrying the combined CH3 variant pairs in HEK293F cells produced the heterodimer, which was purified with more than 90% yield, and retained wild-type Fc biophysical properties. The heterodimeric Fc was exploited to generate a bsAb simultaneously targeting both the Met receptor tyrosine kinase and the VEGF receptor 2 (VEGFR-2), with two respective antigen-specific, single-chain variable fragments (scFv) into the N-terminus. The Met × VEGFR-2 bsAb bound concurrently to the two target antigens, efficiently inhibited the downstream signaling and tube formation stimulated by the two receptors in human endothelial cells, and exhibited more potent antitumor efficacy in MKN45 human gastric cancer xenograft models than both the parent monospecific antibody alone. Collectively, based on the newly designed heterodimeric Fc-based bsAb, our results provide the therapeutic potential of bsAb targeting both Met and VEGFR-2 simultaneously for the treatment of human cancers. Mol Cancer Ther; 12(12); 2748–59. ©2013 AACR.
Data from A Recombinant Immunotoxin against the Tumor-Associated Antigen Mesothelin Reengineered for High Activity, Low Off-Target Toxicity, and Reduced Antigenicity
Authors: Weldon John E. , Xiang Laiman , Zhang Jingli , Beers Richard , Walker Dawn A. , Onda Masanori , Hassan Raffit , Pastan Ira
Published: April 2023

Abstract
SS1P is a recombinant immunotoxin (RIT) engineered for the targeted elimination of malignant cells that express the tumor-associated antigen mesothelin. It is composed of an antimesothelin antibody variable fragment (Fv) linked to a cytotoxic fragment of Pseudomonas exotoxin A (PE) that includes domains II and III of native PE. The clinical use of SS1P is limited by its propensity to induce neutralizing antibodies and to cause a dose-limiting capillary leak syndrome (CLS) in patients. In this article, we describe a reengineered SS1P with improved properties that overcome these deficits. The redesign of SS1P consists of (i) removing the bulk of PE domain II (residues 251–273 and 284–394 of native PE), leaving only an 11-residue furin cleavage site, (ii) adding a Gly–Gly–Ser peptide linker after the furin cleavage site, and (iii) replacing eight highly solvent-exposed residues in the catalytic domain of PE. The new molecule, SS1-LR/GGS/8M, has cytotoxic activity comparable with SS1P on several mesothelin-expressing cell lines and remarkably improved activity on primary cells from patients with mesothelioma. In a mouse xenograft tumor model, high doses of SS1-LR/GGS/8M elicit antitumor activity superior to the activity of SS1P at its maximum-tolerated dose. In addition, SS1-LR/GGS/8M has greatly decreased ability to cause CLS in a rat model and reduced antigenicity or reactivity with antibodies to the sera of patients previously treated with SS1P. Mol Cancer Ther; 12(1); 48–57. ©2012 AACR.
Data from Poly(β-amino ester) Nanoparticle Delivery of TP53 Has Activity against Small Cell Lung Cancer In Vitro and In Vivo
Authors: Kamat Chandrashekhar D. , Shmueli Ron B. , Connis Nick , Rudin Charles M. , Green Jordan J. , Hann Christine L.
Published: April 2023

Abstract
Small cell lung cancer (SCLC) is an aggressive disease with one of the highest case-fatality rates among cancer. The recommended therapy for SCLCs has not changed significantly over the past 30 years; new therapeutic approaches are a critical need. TP53 is mutated in the majority of SCLC cases and its loss is required in transgenic mouse models of the disease. We synthesized an array of biodegradable poly(β-amino ester) (PBAE) polymers that self-assemble with DNA and assayed for transfection efficiency in the p53-mutant H446 SCLC cell line using high-throughput methodologies. Two of the top candidates were selected for further characterization and TP53 delivery in vitro and in vivo. Nanoparticle delivery of TP53 resulted in expression of exogenous p53, induction of p21, induction of apoptosis, and accumulation of cells in sub-G1 consistent with functional p53 activity. Intratumoral injection of subcutaneous H446 xenografts with polymers carrying TP53 caused marked tumor growth inhibition. This is the first demonstration of TP53 gene therapy in SCLC using nonviral polymeric nanoparticles. This technology may have general applicability as a novel anticancer strategy based on restoration of tumor suppressor gene function. Mol Cancer Ther; 12(4); 405–15. ©2013 AACR.
Data from Effect of Small-Molecule–Binding Affinity on Tumor Uptake In Vivo: A Systematic Study Using a Pretargeted Bispecific Antibody
Authors: Orcutt Kelly Davis , Rhoden John J. , Ruiz-Yi Benjamin , Frangioni John V. , Wittrup K. Dane
Published: April 2023

Abstract
Small-molecule ligands specific for tumor-associated surface receptors have wide applications in cancer diagnosis and therapy. Achieving high-affinity binding to the desired target is important for improving detection limits and for increasing therapeutic efficacy. However, the affinity required for maximal binding and retention remains unknown. Here, we present a systematic study of the effect of small-molecule affinity on tumor uptake in vivo with affinities spanning a range of three orders of magnitude. A pretargeted bispecific antibody with different binding affinities to different DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid)-based small molecules is used as a receptor proxy. In this particular system targeting carcinoembryonic antigen, a small-molecule–binding affinity of 400 pmol/L was sufficient to achieve maximal tumor targeting, and an improvement in affinity to 10 pmol/L showed no significant improvement in tumor uptake at 24 hours postinjection. We derive a simple mathematical model of tumor targeting using measurable parameters that correlates well with experimental observations. We use relations derived from the model to develop design criteria for the future development of small-molecule agents for targeted cancer therapeutics. Mol Cancer Ther; 11(6); 1365–72. ©2012 AACR.
Data from Dacomitinib (PF-00299804), an Irreversible Pan-HER Inhibitor, Inhibits Proliferation of HER2-Amplified Breast Cancer Cell Lines Resistant to Trastuzumab and Lapatinib
Authors: Kalous Ondrej , Conklin Dylan , Desai Amrita J. , O'Brien Neil A. , Ginther Charles , Anderson Lee , Cohen David J. , Britten Carolyn D. , Taylor Ian , Christensen James G. , Slamon Dennis J. , Finn Richard S.
Published: April 2023

Abstract
The human EGF (HER) family of receptors has been pursued as therapeutic targets in breast cancer and other malignancies. Trastuzumab and lapatinib are standard treatments for HER2-amplified breast cancer, but a significant number of patients do not respond or develop resistance to these drugs. Here we evaluate the in vitro activity of dacomitinib (PF-00299804), an irreversible small molecule pan-HER inhibitor, in a large panel of human breast cancer cell lines with variable expression of the HER family receptors and ligands, and with variable sensitivity to trastuzumab and lapatinib. Forty-seven human breast cancer and immortalized breast epithelial lines representing the known molecular subgroups of breast cancer were treated with dacomitinib to determine IC50 values. HER2-amplified lines were far more likely to respond to dacomitinib than nonamplified lines (RR, 3.39; P < 0.0001). Furthermore, HER2 mRNA and protein expression were quantitatively associated with response. Dacomitinib reduced the phosphorylation of HER2, EGFR, HER4, AKT, and ERK in the majority of sensitive lines. Dacomitinib exerted its antiproliferative effect through a combined G0–G1 arrest and an induction of apoptosis. Dacomitinib inhibited growth in several HER2-amplified lines with de novo and acquired resistance to trastuzumab. Dacomitinib maintained a high activity in lines with acquired resistance to lapatinib. This study identifies HER2-amplified breast cancer lines as most sensitive to the antiproliferative effect of dacomitinib and provides a strong rationale for its clinical testing in HER2-amplified breast cancers resistant to trastuzumab and lapatinib. Mol Cancer Ther; 11(9); 1978–87. ©2012 AACR.
Data from Synergistic Targeting of PI3K/AKT Pathway and Androgen Receptor Axis Significantly Delays Castration-Resistant Prostate Cancer Progression In Vivo
Authors: Thomas Christian , Lamoureux Francois , Crafter Claire , Davies Barry R. , Beraldi Eliana , Fazli Ladan , Kim Soojin , Thaper Daksh , Gleave Martin E. , Zoubeidi Amina
Published: April 2023

Abstract
The progression to castration-resistant prostate cancer (CRPC) correlates with gain-of-function of the androgen receptor (AR) and activation of AKT. However, as single agents, AR or AKT inhibitors result in a reciprocal feedback loop. Therefore, we hypothesized that combination of an AKT inhibitor with an antiandrogen might result in a more profound, long-lasting remission of CRPC. Here, we report that the AKT inhibitor AZD5363 potently inhibits proliferation and induces apoptosis in prostate cancer cell lines expressing the AR and has anticancer activity in vivo in androgen-sensitive and castration-resistant phases of the LNCaP xenograft model. However, we found that the effect of castration-resistant tumor growth inhibition and prostate-specific antigen (PSA) stabilization is transient and resistance occurs with increasing PSA after approximately 30 days of treatment. Mechanistically, we found that single agent AZD5363 induces increase of AR binding to androgen response element, AR transcriptional activity, and AR-dependent genes such as PSA and NKX3.1 expression. These effects were overcome by the combination of AZD5363 with the antiandrogen bicalutamide, resulting in synergistic inhibition of cell proliferation and induction of apoptosis in vitro, and prolongation of tumor growth inhibition and PSA stabilization in CRPC in vivo. This study provides a preclinical proof-of-concept that combination of an AKT inhibitor with antiandrogen results in prolonged disease stabilization in a model of CRPC. Mol Cancer Ther; 12(11); 2342–55. ©2013 AACR.
Data from Attenuation of Argininosuccinate Lyase Inhibits Cancer Growth via Cyclin A2 and Nitric Oxide
Authors: Huang Hau-Lun , Hsu Hui-Ping , Shieh Shu-Chu , Chang Yung-Sheng , Chen Wei-Ching , Cho Chien-Yu , Teng Chiao-Fang , Su Ih-Jen , Hung Wen-Chun , Lai Ming-Derg
Published: April 2023

Abstract
Arginine biosynthesis and nitric oxide (NO) production are important for cancer homeostasis. Degradation of arginine may be used to inhibit liver tumors with low argininosuccinate synthetase (ASS) expression. In this report, we investigated an alternative therapeutic approach by targeting argininosuccinate lyase (ASL). ASL is transcriptionally induced by endoplasmic reticulum stress and is overexpressed in some human liver tumors. Knockdown of ASL expression by short hairpin RNA (shRNA) in three liver cancer cell lines, ML-1, HuH-7, and HepG2, decreased colony formation in vitro and tumor growth in vivo. Furthermore, lentiviral infection of ASL shRNA inhibited tumor growth in a therapeutic animal tumor model. Analysis of ASL shRNA on the cell-cycle progression revealed a G2–M delay. Among cell-cycle regulatory molecules, cyclin A2 expression was reduced. Reintroduction of exogenous cyclin A2 restored the cell growth in ASL-knockdown cells. Autophagy was observed in the cells treated with ASL shRNA, as shown by an increase in LC3-II levels and autophagosome formation. The total cellular arginine level was not altered significantly. Inhibition of autophagy further attenuated cell growth, suggesting that autophagy induced by ASL shRNA plays a feedback prosurvival function. Knockdown of ASL reduced NO content, and addition of NO donor partially recovered the growth inhibition by ASL shRNA. In summary, downregulation of ASL attenuated tumor growth and the inhibition was mainly mediated by a decrease of cyclin A2 and NO. Mol Cancer Ther; 12(11); 2505–16. ©2013 AACR.
Data from Targeted Mutations in the ATR Pathway Define Agent-Specific Requirements for Cancer Cell Growth and Survival
Authors: Wilsker Deborah , Chung Jon H. , Pradilla Ivan , Petermann Eva , Helleday Thomas , Bunz Fred
Published: April 2023

Abstract
Many anticancer agents induce DNA strand breaks or cause the accumulation of DNA replication intermediates. The protein encoded by ataxia-telangiectasia mutated and Rad 3-related (ATR) generates signals in response to these altered DNA structures and activates cellular survival responses. Accordingly, ATR has drawn increased attention as a potential target for novel therapeutic strategies designed to potentiate the effects of existing drugs. In this study, we use a unique panel of genetically modified human cancer cells to unambiguously test the roles of upstream and downstream components of the ATR pathway in the responses to common therapeutic agents. Upstream, the S-phase–specific cyclin-dependent kinase (Cdk) 2 was required for robust activation of ATR in response to diverse chemotherapeutic agents. While Cdk2-mediated ATR activation promoted cell survival after treatment with many drugs, signaling from ATR directly to the checkpoint kinase Chk1 was required for survival responses to only a subset of the drugs tested. These results show that specifically inhibiting the Cdk2/ATR/Chk1 pathway via distinct regulators can differentially sensitize cancer cells to a wide range of therapeutic agents. Mol Cancer Ther; 11(1); 98–107. ©2011 AACR.
Data from BAY 1000394, a Novel Cyclin-Dependent Kinase Inhibitor, with Potent Antitumor Activity in Mono- and in Combination Treatment upon Oral Application
Authors: Siemeister Gerhard , Lücking Ulrich , Wengner Antje M. , Lienau Philip , Steinke Wolfram , Schatz Christoph , Mumberg Dominik , Ziegelbauer Karl
Published: April 2023

Abstract
Deregulated activity of cyclin-dependent kinases (CDK) results in loss of cell-cycle checkpoint function and increased expression of antiapoptotic proteins, which has been directly linked to the molecular pathology of cancer. BAY 1000394 inhibits the activity of cell-cycle CDKs CDK1, CDK2, CDK3, CDK4, and of transcriptional CDKs CDK7 and CDK9 with IC50 values in the range between 5 and 25 nmol/L. Cell proliferation was inhibited at low nanomolar concentration in a broad spectrum of human cancer cell lines. In cell-based assays, the inhibition of phosphorylation of the CDK substrates retinoblastoma protein, nucleophosmin, and RNA polymerase II was shown. Cell-cycle profiles were consistent with inhibition of CDK 1, 2, and 4 as shown in cell-cycle block and release experiments. The physicochemical and pharmacokinetic properties of BAY 1000394 facilitate rapid absorption and moderate oral bioavailability. The compound potently inhibits growth of various human tumor xenografts on athymic mice including models of chemotherapy resistance upon oral dosing. Furthermore, BAY 1000394 shows more than additive efficacy when combined with cisplatin and etoposide. These results suggest that BAY 1000394 is a potent pan-CDK inhibitor and a novel oral cytotoxic agent currently in phase I clinical trials. Mol Cancer Ther; 11(10); 2265–73. ©2012 AACR.
Data from Uracil–DNA Glycosylase Expression Determines Human Lung Cancer Cell Sensitivity to Pemetrexed
Authors: Weeks Lachelle D. , Fu Pingfu , Gerson Stanton L.
Published: April 2023

Abstract
Uracil misincorporation into DNA is a consequence of pemetrexed inhibition of thymidylate synthase. The base excision repair (BER) enzyme uracil–DNA glycosylase (UNG) is the major glycosylase responsible for removal of misincorporated uracil. We previously illustrated hypersensitivity to pemetrexed in UNG−/− human colon cancer cells. Here, we examined the relationship between UNG expression and pemetrexed sensitivity in human lung cancer. We observed a spectrum of UNG expression in human lung cancer cells. Higher levels of UNG are associated with pemetrexed resistance and are present in cell lines derived from pemetrexed-resistant histologic subtypes (small cell and squamous cell carcinoma). Acute pemetrexed exposure induces UNG protein and mRNA, consistent with upregulation of uracil–DNA repair machinery. Chronic exposure of H1299 adenocarcinoma cells to increasing pemetrexed concentrations established drug-resistant sublines. Significant induction of UNG protein confirmed upregulation of BER as a feature of acquired pemetrexed resistance. Cotreatment with the BER inhibitor methoxyamine overrides pemetrexed resistance in chronically exposed cells, underscoring the use of BER-directed therapeutics to offset acquired drug resistance. Expression of UNG-directed siRNA and shRNA enhanced sensitivity in A549 and H1975 cells, and in drug-resistant sublines, confirming that UNG upregulation is protective. In human lung cancer, UNG deficiency is associated with pemetrexed-induced retention of uracil in DNA that destabilizes DNA replication forks resulting in DNA double-strand breaks and cell death. Thus, in experimental models, UNG is a critical mediator of pemetrexed sensitivity that warrants evaluation to determine clinical value. Mol Cancer Ther; 12(10); 2248–60. ©2013 AACR.
Data from The Novel ATP-Competitive Inhibitor of the MET Hepatocyte Growth Factor Receptor EMD1214063 Displays Inhibitory Activity against Selected MET-Mutated Variants
Authors: Medová Michaela , Pochon Benoît , Streit Bruno , Blank-Liss Wieslawa , Francica Paola , Stroka Deborah , Keogh Adrian , Aebersold Daniel M. , Blaukat Andree , Bladt Friedhelm , Zimmer Yitzhak
Published: April 2023

Abstract
The receptor tyrosine kinase MET is a prime target in clinical oncology due to its aberrant activation and involvement in the pathogenesis of a broad spectrum of malignancies. Similar to other targeted kinases, primary and secondary mutations seem to represent an important resistance mechanism to MET inhibitors. Here, we report the biologic activity of a novel MET inhibitor, EMD1214063, on cells that ectopically express the mutated MET variants M1268T, Y1248H, H1112Y, L1213V, H1112L, V1110I, V1206L, and V1238I. Our results show a dose-dependent decrease in MET autophosphorylation in response to EMD1214063 in five of the eight cell lines (IC50 2–43 nmol/L). Blockade of MET by EMD1214063 was accompanied by a reduced activation of downstream effectors in cells expressing EMD1214063-sensitive mutants. In all sensitive mutant-expressing lines, EMD1214063 altered cell-cycle distribution, primarily with an increase in G1 phase. EMD1214063 strongly influenced MET-driven biologic functions, such as cellular morphology, MET-dependent cell motility, and anchorage-independent growth. To assess the in vivo efficacy of EMD1214063, we used a xenograft tumor model in immunocompromised mice bearing NIH3T3 cells expressing sensitive and resistant MET-mutated variants. Animals were randomized for the treatment with EMD1214063 (50 mg/kg/d) or vehicle only. Remarkably, five days of EMD1214063 treatment resulted in a complete regression of the sensitive H1112L-derived tumors, whereas tumor growth remained unaffected in mice with L1213V tumors and in vehicle-treated animals. Collectively, the current data identifies EMD1214063 as a potent MET small-molecule inhibitor with selective activity towards mutated MET variants. Mol Cancer Ther; 12(11); 2415–24. ©2013 AACR.
Data from CK2 Inhibitor CX-4945 Suppresses DNA Repair Response Triggered by DNA-Targeted Anticancer Drugs and Augments Efficacy: Mechanistic Rationale for Drug Combination Therapy
Authors: Siddiqui-Jain Adam , Bliesath Joshua , Macalino Diwata , Omori Mayuko , Huser Nanni , Streiner Nicole , Ho Caroline B. , Anderes Kenna , Proffitt Chris , O'Brien Sean E. , Lim John K. C. , Von Hoff Daniel D. , Ryckman David M. , Rice William G. , Drygin Denis
Published: April 2023

Abstract
Drug combination therapies are commonly used for the treatment of cancers to increase therapeutic efficacy, reduce toxicity, and decrease the incidence of drug resistance. Although drug combination therapies were originally devised primarily by empirical methods, the increased understanding of drug mechanisms and the pathways they modulate provides a unique opportunity to design combinations that are based on mechanistic rationale. We have identified protein kinase CK2 as a promising therapeutic target for combination therapy, because CK2 regulates not just one but many oncogenic pathways and processes that play important roles in drug resistance, including DNA repair, epidermal growth factor receptor signaling, PI3K/AKT/mTOR signaling, Hsp90 machinery activity, hypoxia, and interleukin-6 expression. In this article, we show that CX-4945, a clinical stage selective small molecule inhibitor of CK2, blocks the DNA repair response induced by gemcitabine and cisplatin and synergizes with these agents in models of ovarian cancer. Mechanistic studies show that the enhanced activity is a result of inactivation of XRCC1 and MDC1, two mediator/adaptor proteins that are essential for DNA repair and that require phosphorylation by CK2 for their function. These data position CK2 as a valid pharmacologic target for intelligent drug combinations and support the evaluation of CX-4945 in combination with gemcitabine and platinum-based chemotherapeutics in the clinical setting. Mol Cancer Ther; 11(4); 994–1005. ©2012 AACR.
Data from IGF-1R/MDM2 Relationship Confers Enhanced Sensitivity to RITA in Ewing Sarcoma Cells
Authors: Di Conza Giusy , Buttarelli Marianna , Monti Olimpia , Pellegrino Marsha , Mancini Francesca , Pontecorvi Alfredo , Scotlandi Katia , Moretti Fabiola
Published: April 2023

Abstract
Ewing sarcoma is one of the most frequent bone cancers in adolescence. Although multidisciplinary therapy has improved the survival rate for localized tumors, a critical step is the development of new drugs to improve the long-term outcome of recurrent and metastatic disease and to reduce side effects of conventional therapy. Here, we show that the small molecule reactivation of p53 and induction of tumor cell apoptosis (RITA, NSC652287) is highly effective in reducing growth and tumorigenic potential of Ewing sarcoma cell lines. These effects occur both in the presence of wt-p53 as well as of mutant or truncated forms of p53, or in its absence, suggesting the presence of additional targets in this tumor histotype. Further experiments provided evidence that RITA modulates an important oncogenic mark of these cell lines, insulin-like growth factor receptor 1 (IGF-1R). Particularly, RITA causes downregulation of IGF-1R protein levels. MDM2 degradative activity is involved in this phenomenon. Indeed, inhibition of MDM2 function by genetic or pharmacologic approaches reduces RITA sensitivity of Ewing sarcoma cell lines. Overall, these data suggest that in the cell context of Ewing sarcoma, RITA may adopt additional mechanism of action besides targeting p53, expanding its field of application. Noteworthy, these results envisage the promising utilization of RITA or its derivative as a potential treatment for Ewing sarcomas. Mol Cancer Ther; 11(6); 1247–56. ©2012 AACR.
Data from Long Pentraxin-3 Inhibits Epithelial–Mesenchymal Transition in Melanoma Cells
Authors: Ronca Roberto , Di Salle Emanuela , Giacomini Arianna , Leali Daria , Alessi Patrizia , Coltrini Daniela , Ravelli Cosetta , Matarazzo Sara , Ribatti Domenico , Vermi William , Presta Marco
Published: April 2023

Abstract
During melanoma progression, malignant melanocytes are reprogrammed into mesenchymal-like cells through to an epithelial–mesenchymal transition (EMT) process associated with the acquisition of an invasive, prometastatic phenotype. The fibroblast growth factor-2 (FGF2)/FGF receptor (FGFR) system plays a pivotal role in melanoma, leading to autocrine/paracrine induction of tumor cell proliferation and angiogenesis. Long pentraxin-3 (PTX3) interacts with FGF2, and other FGF family members, inhibiting FGF-dependent neovascularization and tumor growth. Here, PTX3 protein and the PTX3-derived acetylated pentapeptide Ac-ARPCA-NH2 inhibit FGF2-driven proliferation and downstream FGFR signaling in murine melanoma B16-F10 cells. Moreover, human PTX3-overexpressing hPTX_B16-F10 cells are characterized by the reversed transition from a mesenchymal to an epithelial-like appearance, inhibition of cell proliferation, loss of clonogenic potential, reduced motility and invasive capacity, downregulation of various mesenchymal markers, and upregulation of the epithelial marker E-cadherin. Accordingly, PTX3 affects cell proliferation and EMT transition in human A375 and A2058 melanoma cells. Also, hPTX_B16-F10 cells showed a reduced tumorigenic and metastatic activity in syngeneic C57BL/6 mice. In conclusion, PTX3 inhibits FGF/FGFR-driven EMT in melanoma cells, hampering their tumorigenic and metastatic potential. These data represent the first experimental evidence about a nonredundant role of the FGF/FGFR system in the modulation of the EMT process in melanoma and indicate that PTX3 or its derivatives may represent the basis for the design of novel therapeutic approaches in FGF/FGFR-dependent tumors, including melanoma. Mol Cancer Ther; 12(12); 2760–71. ©2013 AACR.
Data from Designing and Developing S100P Inhibitor 5-Methyl Cromolyn for Pancreatic Cancer Therapy
Authors: Arumugam Thiruvengadam , Ramachandran Vijaya , Sun Duoli , Peng Zhenghong , Pal Ashutosh , Maxwell David S. , Bornmann William G. , Logsdon Craig D.
Published: April 2023

Abstract
We have previously shown that the antiallergic drug cromolyn blocks S100P interaction with its receptor receptor for advanced glycation end product (RAGE) and improves gemcitabine effectiveness in pancreatic ductal adenocarcinoma (PDAC). However, the concentration required to achieve its effectiveness was high (100 μmol/L). In this study, we designed and synthesized analogs of cromolyn and analyzed their effectiveness compared with the parent molecule. An ELISA was used to confirm the binding of S100P with RAGE and to test the effectiveness of the different analogs. Analog 5-methyl cromolyn (C5OH) blocked S100P binding as well as the increases in NF-κB activity, cell growth, and apoptosis normally caused by S100P. In vivo C5OH systemic delivery reduced NF-κB activity to a greater extent than cromolyn and at 10 times lesser dose (50 mg vs. 5 mg). Treatment of mice-bearing syngeneic PDAC tumors showed that C5OH treatment reduced both tumor growth and metastasis. C5OH treatment of nude mice bearing orthotopic highly aggressive pancreatic Mpanc96 cells increased the overall animal survival. Therefore, the cromolyn analog, C5OH, was found to be more efficient and potent than cromolyn as a therapeutic for PDAC. Mol Cancer Ther; 12(5); 654–62. ©2013 AACR.
Data from Novel Immunotherapy for Malignant Melanoma with a Monoclonal Antibody That Blocks CEACAM1 Homophilic Interactions
Authors: Ortenberg Rona , Sapir Yair , Raz Lee , Hershkovitz Liat , Ben Arav Ayelet , Sapoznik Sivan , Barshack Iris , Avivi Camila , Berkun Yackov , Besser Michal J. , Ben-Moshe Tehila , Schachter Jacob , Markel Gal
Published: April 2023

Abstract
CEACAM1 (biliary glycoprotein-1, CD66a) was reported as a strong clinical predictor of poor prognosis in melanoma. We have previously identified CEACAM1 as a tumor escape mechanism from cytotoxic lymphocytes. Here, we present substantial evidence in vitro and in vivo that blocking of CEACAM1 function with a novel monoclonal antibody (MRG1) is a promising strategy for cancer immunotherapy. MRG1, a murine IgG1 monoclonal antibody, was raised against human CEACAM1. It recognizes the CEACAM1-specific N-domain with high affinity (KD ∼ 2 nmol/L). Furthermore, MRG1 is a potent inhibitor of CEACAM1 homophilic binding and does not induce any agonistic effect. We show using cytotoxicity assays that MRG1 renders multiple melanoma cell lines more vulnerable to T cells in a dose-dependent manner, only following antigen-restricted recognition. Accordingly, MRG1 significantly enhances the antitumor effect of adoptively transferred, melanoma-reactive human lymphocytes using human melanoma xenograft models in severe combined immunodeficient/nonobese diabetic (SCID/NOD) mice. A significant antibody-dependent cell cytotoxicity response was excluded. It is shown that MRG1 reaches the tumor and is cleared within a week. Importantly, approximately 90% of melanoma specimens are CEACAM1+, implying that the majority of patients with melanoma could be amenable to MRG1-based therapy. Normal human tissue microarray displays limited binding to luminal epithelial cells on some secretory ducts, which was weaker than the broad normal cell binding of other anticancer antibodies in clinical use. Importantly, MRG1 does not directly affect CEACAM1+ cells. CEACAM1 blockade is different from other immunomodulatory approaches, as MRG1 targets inhibitory interactions between tumor cells and late effector lymphocytes, which is thus a more specific and compartmentalized immune stimulation with potentially superior safety profile. Mol Cancer Ther; 11(6); 1300–10. ©2012 AACR.
Data from Capillary Isoelectric-Focusing Immunoassays to Study Dynamic Oncoprotein Phosphorylation and Drug Response to Targeted Therapies in Non–Small Cell Lung Cancer
Authors: Chen Jin-Qiu , Lee Jih-Hsiang , Herrmann Michelle A. , Park Kang-Seo , Heldman Madeleine R. , Goldsmith Paul K. , Wang Yisong , Giaccone Giuseppe
Published: April 2023

Abstract
Developing proteomic biomarkers is valuable for evaluating therapeutic effects of drugs and generating better treatment strategies. However, conventional protein analysis is often challenging due to inadequate sample size of clinical specimens, lack of assay reproducibility, accuracy, and sensitivity. A novel capillary isoelectricfocusing (IEF) immunoassay system (NanoPro) was used to study the dynamic phosphorylation status of signaling molecules in non–small cell lung cancer (NSCLC) cells treated with EGFR tyrosine kinase and MEK inhibitors. NanoPro showed the same dynamic ERK phosphorylation as Western blotting with good assay reproducibility using 1,000 times less protein. The IEF separation in NanoPro system enables multiple protein phosphorylation isoforms to be resolved and detected simultaneously. With NanoPro, we identified a specific on-target mitogen-activated protein/extracellular signal–regulated kinase (MEK) response pattern to MEK inhibitor PD325901, which was not detectable by Western blot analysis. We also revealed a MEK2 signal that may be associated with NSCLC cell sensitivity to the EGF receptor inhibitor erlotinib, and distinguished erlotinib-sensitive cells from intrinsic as well as acquired resistant cells to erlotinib. Moreover, NanoPro could differentiate human ERK1 isoforms from the mouse isoforms based on their isoelectric point differences and showed that erlotinib effectively inhibited ERK phosphorylation in targeted human xenograft cancer cells but not in surrounding mouse stromal cells. With 8 μg of tumor aspirates, we precisely quantified the response of 18 signaling molecules to erlotinib and MEK1 inhibitor treatments in an NSCLC patient. NanoPro's higher sensitivity, better resolution of protein phosphorylation status, and reduced tissue requirement warrant NanoPro's investigation for future drug development and evaluation of drug effects of targeted therapies. Mol Cancer Ther; 12(11); 2601–13. ©2013 AACR.
Data from Fibroblast Growth Factor Receptor 2 IIIc as a Therapeutic Target for Colorectal Cancer Cells
Authors: Matsuda Yoko , Hagio Masahito , Seya Tomoko , Ishiwata Toshiyuki
Published: April 2023

Abstract
A high percentage of colorectal carcinomas overexpress a lot of growth factors and their receptors, including fibroblast growth factor (FGF) and FGF receptor (FGFR). We previously reported that FGFR2 overexpression was associated with distant metastasis and that FGFR2 inhibition suppressed cell growth, migration, and invasion. The FGFR2 splicing isoform FGFR2IIIb is associated with well-differentiated histologic type, tumor angiogenesis, and adhesion to extracellular matrices. Another isoform, FGFR2IIIc, correlates with the aggressiveness of various types of cancer. In the present study, we examined the expression and roles of FGFR2IIIc in colorectal carcinoma to determine the effectiveness of FGFR2IIIc-targeting therapy. In normal colorectal tissues, FGFR2IIIc expression was weakly detected in superficial colorectal epithelial cells and was not detected in proliferative zone cells. FGFR2IIIc-positive cells were detected by immunohistochemistry in the following lesions, listed in the order of increasing percentage: hyperplastic polyps < low-grade adenomas < high-grade adenomas < carcinomas. FGFR2IIIc immunoreactivity was expressed in 27% of colorectal carcinoma cases, and this expression correlated with distant metastasis and poor prognosis. FGFR2IIIc-transfected colorectal carcinoma cells showed increased cell growth, soft agar colony formation, migration, and invasion, as well as decreased adhesion to extracellular matrices. Furthermore, FGFR2IIIc-transfected colorectal carcinoma cells formed larger tumors in subcutaneous tissues and the cecum of nude mice. Fully human anti-FGFR2IIIc monoclonal antibody inhibited the growth and migration of colorectal carcinoma cells through alterations in cell migration, cell death, and development-related genes. In conclusion, FGFR2IIIc plays an important role in colorectal carcinogenesis and tumor progression. Monoclonal antibody against FGFR2IIIc has promising potential in colorectal carcinoma therapy. Mol Cancer Ther; 11(9); 2010–20. ©2012 AACR.
Data from Targeting the PI3K/mTOR Axis, Alone and in Combination with Autophagy Blockade, for the Treatment of Malignant Peripheral Nerve Sheath Tumors
Authors: Ghadimi Markus P. , Lopez Gonzalo , Torres Keila E. , Belousov Roman , Young Eric D. , Liu Jeffery , Brewer Kari J. , Hoffman Aviad , Lusby Kristelle , Lazar Alexander J. , Pollock Raphael E. , Lev Dina
Published: April 2023

Abstract
There is a critical need for efficacious therapeutic strategies to improve the outcome of patients afflicted by malignant peripheral nerve sheath tumors (MPNST). Multiple lines of evidence suggest a role for deregulated phosphoinositide 3-kinase (PI3K)/mTOR signaling in MPNST, making this axis an attractive target for therapeutic manipulation. On the basis of previous observations obtained from in vitro experimentation, here we aimed to assess the effects of PI3K/mTOR blockade on MPNST growth in vivo. The anti-MPNST impact of XL765, a dual PI3K/mTOR inhibitor currently being evaluated in human cancer clinical trials, was tested in two human MPNST xenograft models (STS26T and MPNST724) and an experimental model of pulmonary metastasis (STS26T). XL765 abrogated human MPNST local and metastatic growth in severe combined immunodeficient mice. Notably, this therapeutic approach failed to induce apoptosis in MPNST cells but rather resulted in marked productive autophagy. Importantly, genetic and pharmacologic autophagy blockade reversed apoptotic resistance and resulted in significant PI3K/mTOR inhibition-induced MPNST cell death. The addition of the autophagy inhibitor, chloroquine, to the therapeutic regimen of MPNST xenografts after pretreatment with XL765 resulted in superior antitumor effects as compared with either agent alone. Together, preclinical studies described here expand our previous findings and suggest that PI3K/mTOR inhibition alone and (most importantly) in combination with autophagy blockade may comprise a novel and efficacious therapy for patients harboring MPNST. Mol Cancer Ther; 11(8); 1758–69. ©2012 AACR.
Data from Preclinical Analysis of the γ-Secretase Inhibitor PF-03084014 in Combination with Glucocorticoids in T-cell Acute Lymphoblastic Leukemia
Authors: Samon Jeremy B. , Castillo-Martin Mireia , Hadler Michael , Ambesi-Impiobato Alberto , Paietta Elisabeth , Racevskis Janis , Wiernik Peter H. , Rowe Jacob M. , Jakubczak John , Randolph Sophia , Cordon-Cardo Carlos , Ferrando Adolfo A.
Published: April 2023

Abstract
T-cell acute lymphoblastic leukemias (T-ALL) and lymphomas are aggressive hematologic cancers frequently associated with activating mutations in NOTCH1. Early studies identified NOTCH1 as an attractive therapeutic target for the treatment of T-ALL through the use of γ-secretase inhibitors (GSI). Here, we characterized the interaction between PF-03084014, a clinically relevant GSI, and dexamethasone in preclinical models of glucocorticoid-resistant T-ALL. Combination treatment of the GSI PF-03084014 with glucocorticoids induced a synergistic antileukemic effect in human T-ALL cell lines and primary human T-ALL patient samples. Mechanistically PF-03084014 plus glucocorticoid treatment induced increased transcriptional upregulation of the glucocorticoid receptor and glucocorticoid target genes. Treatment with PF-03084014 and glucocorticoids in combination was highly efficacious in vivo, with enhanced reduction of tumor burden in a xenograft model of T-ALL. Finally, glucocorticoid treatment effectively reversed PF-03084014–induced gastrointestinal toxicity via inhibition of goblet cell metaplasia. These results warrant the analysis of PF-03084014 and glucocorticoids in combination for the treatment of glucocorticoid-resistant T-ALL. Mol Cancer Ther; 11(7); 1565–75. ©2012 AACR.
Data from MUC13 Mucin Augments Pancreatic Tumorigenesis
Authors: Chauhan Subhash C. , Ebeling Mara C. , Maher Diane M. , Koch Michael D. , Watanabe Akira , Aburatani Hiroyuki , Lio Yuhlong , Jaggi Meena
Published: April 2023

Abstract
The high death rate of pancreatic cancer is attributed to the lack of reliable methods for early detection and underlying molecular mechanisms of its aggressive pathogenesis. Although MUC13, a newly identified transmembrane mucin, is known to be aberrantly expressed in ovarian and gastro-intestinal cancers, its role in pancreatic cancer is unknown. Herein, we investigated the expression profile and functions of MUC13 in pancreatic cancer progression. The expression profile of MUC13 in pancreatic cancer was investigated using a recently generated monoclonal antibody (clone PPZ0020) and pancreatic tissue microarrays. The expression of MUC13 was significantly (P < 0.005) higher in cancer samples compared with normal/nonneoplastic pancreatic tissues. For functional analyses, full-length MUC13 was expressed in MUC13 null pancreatic cancer cell lines, MiaPaca and Panc1. MUC13 overexpression caused a significant (P < 0.05) increase in cell motility, invasion, proliferation, and anchorage-dependent or -independent clonogenicity while decreasing cell–cell and cell-substratum adhesion. Exogenous MUC13 expression significantly (P < 0.05) enhanced pancreatic tumor growth and reduced animal survival in a xenograft mouse model. These tumorigenic characteristics correlated with the upregulation/phosphorylation of HER2, p21-activated kinase 1 (PAK1), extracellular signal-regulated kinase (ERK), Akt, and metastasin (S100A4), and the suppression of p53. Conversely, suppression of MUC13 in HPAFII pancreatic cancer cells by short hairpin RNA resulted in suppression of tumorigenic characteristics, repression of HER2, PAK1, ERK, and S100A4, and upregulation of p53. MUC13 suppression also significantly (P < 0.05) reduced tumor growth and increased animal survival. These results imply a role of MUC13 in pancreatic cancer and suggest its potential use as a diagnostic and therapeutic target. Mol Cancer Ther; 11(1); 24–33. ©2011 AACR.
Data from Inhibition of Insulin-like Growth Factor–Binding Protein-3 Signaling through Sphingosine Kinase-1 Sensitizes Triple-Negative Breast Cancer Cells to EGF Receptor Blockade
Authors: Martin Janet L. , de Silva Hasanthi C. , Lin Mike Z. , Scott Carolyn D. , Baxter Robert C.
Published: April 2023

Abstract
The type I EGF receptor (EGFR or ErbB1) and insulin-like growth factor–binding protein-3 (IGFBP-3) are highly expressed in triple-negative breast cancer (TNBC), a particularly aggressive disease that cannot be treated with conventional therapies targeting the estrogen or progesterone receptors (ER and PR), or HER2. We have shown previously in normal breast epithelial cells that IGFBP-3 potentiates growth-stimulatory signaling transduced by EGFR, and this is mediated by the sphingosine kinase-1 (SphK1)/sphingosine 1-phosphate (S1P) system. In this study, we investigated whether cotargeting the EGFR and SphK1/S1P pathways in TNBC cells results in greater growth inhibition compared with blocking either alone, and might therefore have novel therapeutic potential in TNBC. In four TNBC cell lines, exogenous IGFBP-3 enhanced ligand-stimulated EGFR activation, associated with increased SphK1 localization to the plasma membrane. The effect of exogenous IGFBP-3 on EGFR activation was blocked by pharmacologic inhibition or siRNA-mediated silencing of SphK1, and silencing of endogenous IGFBP-3 also suppressed EGF-stimulated EGFR activation. Real-time analysis of cell proliferation revealed a combined effect of EGFR inhibition by gefitinib and SphK1 inhibition using SKi-II. Growth of MDA-MB-468 xenograft tumors in mice was significantly inhibited by SKi-II and gefitinib when used in combination, but not as single agents. We conclude that IGFBP-3 promotes growth of TNBC cells by increasing EGFR signaling, that this is mediated by SphK1, and that combined inhibition of EGFR and SphK1 has potential as an anticancer therapy in TNBC in which EGFR and IGFBP-3 expression is high. Mol Cancer Ther; 13(2); 316–28. ©2013 AACR.
Data from Pharmacologic Inhibition of MEK Signaling Prevents Growth of Canine Hemangiosarcoma
Authors: Andersen Nicholas J. , Nickoloff Brian J. , Dykema Karl J. , Boguslawski Elissa A. , Krivochenitser Roman I. , Froman Roe E. , Dawes Michelle J. , Baker Laurence H. , Thomas Dafydd G. , Kamstock Debra A. , Kitchell Barbara E. , Furge Kyle A. , Duesbery Nicholas S.
Published: April 2023

Abstract
Angiosarcoma is a rare neoplasm of endothelial origin that has limited treatment options and poor five-year survival. As a model for human angiosarcoma, we studied primary cells and tumorgrafts derived from canine hemangiosarcoma (HSA), which is also an endothelial malignancy with similar presentation and histology. Primary cells isolated from HSA showed constitutive extracellular signal–regulated kinase (ERK) activation. The mitogen-activated protein/extracellular signal–regulated kinase (MEK) inhibitor CI-1040 reduced ERK activation and the viability of primary cells derived from visceral, cutaneous, and cardiac HSA in vitro. HSA-derived primary cells were also sensitive to sorafenib, an inhibitor of B-Raf and multireceptor tyrosine kinases. In vivo, CI-1040 or PD0325901 decreased the growth of cutaneous cell-derived xenografts and cardiac-derived tumorgrafts. Sorafenib decreased tumor size in both in vivo models, although cardiac tumorgrafts were more sensitive. In human angiosarcoma, we noted that 50% of tumors stained positively for phosphorylated ERK1/2 and that the expression of several MEK-responsive transcription factors was upregulated. Our data showed that MEK signaling is essential for the growth of HSA in vitro and in vivo and provided evidence that the same pathways are activated in human angiosarcoma. This indicates that MEK inhibitors may form part of an effective therapeutic strategy for the treatment of canine HSA or human angiosarcoma, and it highlights the use of spontaneous canine cancers as a model of human disease. Mol Cancer Ther; 12(9); 1701–14. ©2013 AACR.
Data from CBS9106-Induced CRM1 Degradation Is Mediated by Cullin Ring Ligase Activity and the Neddylation Pathway
Authors: Saito Naoya , Sakakibara Keiichi , Sato Takuji , Friedman Jonathan M. , Kufe Donald W. , VonHoff Daniel D. , Kawabe Takumi
Published: April 2023

Abstract
Chromosome region maintenance 1 (CRM1) mediates the nuclear export of proteins and mRNAs, and is overexpressed in various cancers. Recent studies have also reported that CRM1 protein expression is a negative prognostic factor in patients with cancer. Therefore, CRM1 is considered a potential target for anticancer therapy. Our previous study demonstrated that CBS9106, a synthetic small-molecular inhibitor of CRM1, decreases CRM1 protein through proteasomal degradation without affecting CRM1 mRNA levels. However, the mechanism by which CRM1 is degraded is not well understood. Here, we demonstrate a novel signaling pathway that plays an important role in CBS9106-induced CRM1 degradation. We found that MLN4924, a selective inhibitor of NEDD8-activating enzyme (NAE), effectively inhibits cullin neddylation and attenuates CBS9106-induced CRM1 degradation in a time- and dose-dependent manner. MLN4924 also attenuated CBS9106-induced nuclear accumulation of Ran-binding protein 1 (RanBP1), cell growth inhibition, and apoptosis. Furthermore, RNAi-mediated knockdown of neddylation pathway proteins (NEDD8 and UBA3) or cullin ring ligase (CRL) component protein (Rbx1) attenuated CRM1 protein degradation and G1 phase cell-cycle arrest by CBS9106. Knockdown of CSN5 or CAND1 also partially inhibited CBS9106-induced CRM1 degradation. These findings demonstrate that CBS9106-induced CRM1 degradation is conferred by CRL activity involving the neddylation pathway, and that this response to CBS9106 leads to cell growth inhibition and apoptosis. Mol Cancer Ther; 13(12); 3013–23. ©2014 AACR.