bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Endothelial Cell–Specific Deletion of Transcription Factor FoxM1 Increases Urethane-Induced Lung Carcinogenesis
Authors: Balli David , Zhang Yufang , Snyder Jonathan , Kalinichenko Vladimir V. , Kalin Tanya V.
Published: March 2024

Abstract
Vascular endothelial cells provide essential support to the tumor microenvironment, but little is known about the transcriptional control of endothelial functions during tumorigenesis. Here we define a critical role for the Forkhead transcription factor FoxM1 in modulating the development of tumor-associated endothelial cells. Pulmonary tumorigenesis induced by urethane administration was compared in mice genetically deleted for FoxM1 in endothelial cells (enFoxm1−/− mice). Notably, lung tumor number and size were increased in enFoxm1−/− mice. Increased tumorigenesis was associated with increased proliferation of tumor cells and increased expression of c-Myc and cyclin D1. Furthermore, perivascular infiltration by inflammatory cells was elevated and inflammatory cells in BAL fluid were increased. Expression of Flk-1 (vascular endothelial growth factor receptor 2) and FoxF1, known regulators of pulmonary inflammation, was decreased in enFoxm1−/− mice. siRNA-mediated knockdown of FoxM1 in endothelial cells reduced Flk-1 and FoxF1 expression, which was driven by direct transcriptional induction by FoxM1 as target genes. Endothelial specific deletion of FoxM1 in vivo or in vitro also decreased expression of Sfrp1 (secreted frizzled-related protein 1), a known inhibitor of canonical Wnt signaling, in a manner that was associated with increased Wnt signaling. Taken together, our results suggest that endothelial-specific expression of FoxM1 limits lung inflammation and canonical Wnt signaling in lung epithelial cells, thereby restricting lung tumorigenesis. Cancer Res; 71(1); 40–50. ©2011 AACR.
Data from BRCA2 and Nucleophosmin Coregulate Centrosome Amplification and Form a Complex with the Rho Effector Kinase ROCK2
Authors: Wang Hui-Feng , Takenaka Katsuya , Nakanishi Akira , Miki Yoshio
Published: March 2024

Abstract
BRCA2 germline mutations account for the majority of heredity breast and ovarian cancer. Besides its role in DNA damage repair, BRCA2 also plays an important role in cytokinesis, transcription regulation, and cancer cell proliferation. Recently, we reported that BRCA2 localizes to centrosomes as well as nuclei and the dysfunction of BRCA2 in a centrosome causes abnormalities in cell division. Here, we identified a nucleolar phosphoprotein, nucleophosmin (NPM), as a novel BRCA2-associated protein. We also detected the binding of BRCA2 to ROCK2, an effector of Rho small GTPase. Because it is known that ROCK2 binds to NPM at centrosomes, these 3 proteins may form a complex. NPM-binding region was within amino acids 639–1,000 of BRCA2. Exogenous expression of this BRCA2 region resulted in aberrant centrosome amplification and a high frequency of multinucleated cells. Our results suggested that a complex consisting of BRCA2, NPM, and ROCK2 maintains the numerical integrity of centrosomes and accurate cell division and that dysfunction of this regulation might be involved in the tumorigenesis of breast cancer. Cancer Res; 71(1); 68–77. ©2011 AACR.
Data from Antitumor and Anti-inflammatory Effects of Trabectedin on Human Myxoid Liposarcoma Cells
Authors: Germano Giovanni , Frapolli Roberta , Simone Matteo , Tavecchio Michele , Erba Eugenio , Pesce Samantha , Pasqualini Fabio , Grosso Federica , Sanfilippo Roberta , Casali Paolo G. , Gronchi Alessandro , Virdis Emanuela , Tarantino Eva , Pilotti Silvana , Greco Angela , Nebuloni Manuela , Galmarini Carlos Maria , Tercero Juan Carlos , Mantovani Alberto , D'Incalci Maurizio , Allavena Paola
Published: March 2024

Abstract
Inflammatory mediators present in the tumor milieu may promote cancer progression and are considered promising targets of novel biological therapies. We previously reported that the marine antitumor agent trabectedin, approved in Europe in 2007 for soft tissue sarcomas and in 2009 for ovarian cancer, was able to downmodulate the production of selected cytokines/chemokines in immune cells. Patients with myxoid liposarcoma (MLS), a subtype characterized by the expression of the oncogenic transcript FUS-CHOP, are highly responsive to trabectedin. The drug had marked antiproliferative effects on MLS cell lines at low nanomolar concentrations. We tested the hypothesis that trabectedin could also affect the inflammatory mediators produced by cancer cells. Here, we show that MLS express several cytokines, chemokines, and growth factors (CCL2, CCL3, CCL5, CXCL8, CXCL12, MIF, VEGF, SPARC) and the inflammatory and matrix-binder protein pentraxin 3 (PTX3), which build up a prominent inflammatory environment. In vitro treatment with noncytotoxic concentrations of trabectedin selectively inhibited the production of CCL2, CXCL8, IL-6, VEGF, and PTX3 by MLS primary tumor cultures and/or cell lines. A xenograft mouse model of human MLS showed marked reduction of CCL2, CXCL8, CD68+ infiltrating macrophages, CD31+ tumor vessels, and partial decrease of PTX3 after trabectedin treatment. Similar findings were observed in a patient tumor sample excised after several cycles of therapy, indicating that the results observed in vitro might have in vivo relevance. In conclusion, trabectedin has dual effects in liposarcoma: in addition to direct growth inhibition, it affects the tumor microenvironment by reducing the production of key inflammatory mediators. Cancer Res; 70(6); 2235–44
Data from Epigenetic Silencing of MicroRNA-203 Dysregulates ABL1 Expression and Drives Helicobacter-Associated Gastric Lymphomagenesis
Authors: Craig Vanessa J. , Cogliatti Sergio B. , Rehrauer Hubert , Wündisch Thomas , Müller Anne
Published: March 2024

Abstract
Gastric B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) develops in the chronically inflamed mucosa of patients infected with the bacterial pathogen Helicobacter pylori. Here we use patient material, primary gastric lymphoma cell cultures, and a preclinical model of the disease to examine the role of microRNA (miRNA)-mediated posttranscriptional regulation—focusing in particular on miR-203 and its target ABL1—in gastric MALT lymphomagenesis. Microarray-based miRNA expression profiling revealed a strong downregulation of the putative tumor suppressor miRNA miR-203 in human MALT lymphoma samples, which resulted from extensive promoter hypermethylation of the miR-203 locus and coincided with the dysregulation of the miR-203 target ABL1 in lymphoma biopsies compared with matched adjacent normal material from the same patients. Treatment of lymphoma B cells with demethylating agents led to increased miR-203 expression and the concomitant downregulation of ABL1, confirming the epigenetic regulation of this miRNA. Ectopic reexpression of miR-203 by transfection of a human lymphoma cell line or lentiviral transduction of explanted primary MALT lymphoma cells was sufficient to prevent tumor cell proliferation in vitro. Similarly, the treatment of primary MALT lymphoma cells with the ABL inhibitors imatinib and dasatinib prevented tumor cell growth. Finally, we show that the treatment of tumor-bearing mice with imatinib induces MALT lymphoma regression in a preclinical model of the disease, implicating ABL1 in MALT lymphoma progression. In summary, our results show that the transformation from gastritis to MALT lymphoma is epigenetically regulated by miR-203 promoter methylation and identify ABL1 as a novel target for the treatment of this malignancy. Cancer Res; 71(10); 3616–24. ©2011 AACR.
Data from LATS2 Is a Tumor Suppressor Gene of Malignant Mesothelioma
Authors: Murakami Hideki , Mizuno Tetsuya , Taniguchi Tetsuo , Fujii Makiko , Ishiguro Futoshi , Fukui Takayuki , Akatsuka Shinya , Horio Yoshitsugu , Hida Toyoaki , Kondo Yutaka , Toyokuni Shinya , Osada Hirotaka , Sekido Yoshitaka
Published: March 2024

Abstract
Malignant mesothelioma (MM) is an aggressive neoplasm associated with asbestos exposure. We carried out genome-wide array-based comparative genomic hybridization analysis with 14 MM cell lines. Three cell lines showed overlapping homozygous deletion at chromosome 13q12, which harbored the LATS2 (large tumor suppressor homolog 2) gene. With 6 other MM cell lines and 25 MM tumors, we found 10 inactivating homozygous deletions or mutations of LATS2 among 45 MMs. LATS2 encodes a serine/threonine kinase, a component of the Hippo tumor-suppressive signaling pathway, and we transduced LATS2 in MM cells with its mutation. Transduction of LATS2 inactivated oncoprotein YAP, a transcriptional coactivator, via phosphorylation, and inhibited MM cell growth. We also analyzed LATS2 immunohistochemically and found that 13 of 45 MM tumors had low expression of LATS2. Because NF2 is genetically mutated in 40% to 50% of MM, our data indicate that Hippo pathway dysregulation is frequent in MM cells with inactivation of LATS2 or an upstream regulator of this pathway, Merlin, which is encoded by NF2. Thus, our results suggest that the inactivation of LATS2 is one of the key mechanisms for constitutive activation of YAP, which induces deregulation of MM cell proliferation. Cancer Res; 71(3); 873–83. ©2011 AACR.
Data from MicroRNA Replacement Therapy for miR-145 and miR-33a Is Efficacious in a Model of Colon Carcinoma
Authors: Ibrahim Ahmed Fawzy , Weirauch Ulrike , Thomas Maren , Grünweller Arnold , Hartmann Roland K. , Aigner Achim
Published: March 2024

Abstract
MicroRNAs (miRNA) aberrantly expressed in tumors may offer novel therapeutic approaches to treatment. miR-145 is downregulated in various cancers including colon carcinoma in which in vitro studies have established proapoptotic and antiproliferative roles. miR-33a was connected recently to cancer through its capacity to downregulate the oncogenic kinase Pim-1. To date, miRNA replacement therapy has been hampered by the lack of robust nonviral delivery methods for in vivo administration. Here we report a method of miRNA delivery by using polyethylenimine (PEI)-mediated delivery of unmodified miRNAs, using miR-145 and miR-33a to preclinically validate the method in a mouse model of colon carcinoma. After systemic or local application of low molecular weight PEI/miRNA complexes, intact miRNA molecules were delivered into mouse xenograft tumors, where they caused profound antitumor effects. miR-145 delivery reduced tumor proliferation and increased apoptosis, with concomitant repression of c-Myc and ERK5 as novel regulatory target of miR-145. Similarly, systemic injection of PEI-complexed miR-33a was validated as a novel therapeutic targeting method for Pim-1, with antitumor effects comparable with PEI/siRNA-mediated direct in vivo knockdown of Pim-1 in the model. Our findings show that chemically unmodified miRNAs complexed with PEI can be used in an efficient and biocompatible strategy of miRNA replacement therapy, as illustrated by efficacious delivery of PEI/miR-145 and PEI/miR-33a complexes in colon carcinoma. Cancer Res; 71(15); 5214–24. ©2011 AACR.
Data from Agonist Anti-CD137 mAb Act on Tumor Endothelial Cells to Enhance Recruitment of Activated T Lymphocytes
Authors: Palazón Asís , Teijeira Alvaro , Martínez-Forero Iván , Hervás-Stubbs Sandra , Roncal Carmen , Peñuelas Iván , Dubrot Juan , Morales-Kastresana Aizea , Pérez-Gracia José Luis , Ochoa M. Carmen , Ochoa-Callejero Laura , Martínez Alfredo , Luque Alfonso , Dinchuk Joseph , Rouzaut Ana , Jure-Kunkel Maria , Melero Ignacio
Published: March 2024

Abstract
Agonist monoclonal antibodies (mAb) to the immune costimulatory molecule CD137, also known as 4-1BB, are presently in clinical trials for cancer treatment on the basis of their costimulatory effects on primed T cells and perhaps other cells of the immune system. Here we provide evidence that CD137 is selectively expressed on the surface of tumor endothelial cells. Hypoxia upregulated CD137 on murine endothelial cells. Treatment of tumor-bearing immunocompromised Rag−/− mice with agonist CD137 mAb did not elicit any measurable antiangiogenic effects. In contrast, agonist mAb stimulated tumor endothelial cells, increasing cell surface expression of the adhesion molecules intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, and E-selectin. When adoptively transferred into mice, activated T lymphocytes derived from CD137-deficient animals entered more avidly into tumor tissue after treatment with agonist mAb. This effect could be neutralized with anti–ICAM-1 and anti–VCAM-1 blocking antibodies. Thus, stimulation of CD137 not only enhanced T-cell activation but also augmented their trafficking into malignant tissue, through direct actions on the blood vessels that irrigate the tumor. Our findings identify an additional mechanism of action that can explain the immunotherapeutic effects of agonist CD137 antibodies. Cancer Res; 71(3); 801–11. ©2011 AACR.
Data from Anti-TIM3 Antibody Promotes T Cell IFN-γ–Mediated Antitumor Immunity and Suppresses Established Tumors
Authors: Ngiow Shin Foong , von Scheidt Bianca , Akiba Hisaya , Yagita Hideo , Teng Michele W. L. , Smyth Mark J.
Published: March 2024

Abstract
Strategies to activate and rescue exhausted tumor-specific T cells, including the use of monoclonal antibodies (mAb) that block the negative costimulatory receptors CTLA-4 and PD-1 are proving very effective, but TIM3 has been relatively neglected as a target. Here we report an extensive characterization of the therapeutic activity and mechanism of action of an anti-mouse TIM3 mAb against experimental and carcinogen-induced tumors. For the first time we specifically define the mechanism of antitumor action of anti-TIM3 requiring IFN-γ producing CD8+ T cells and CD4+ T cells, and a higher ratio of tumor infiltrating CD8+:CD4+ T cells correlating with therapeutic success. Interestingly, in some models, anti-TIM3 appeared to be effective sometime before the appearance and accumulation of significant TIM3+PD-1+ T cell populations in tumor bearing mice. Anti-TIM3 displayed modest prophylactic and therapeutic activity against a small fraction of carcinogen-induced sarcomas, but comparative and combination studies of anti-TIM3 with anti-CTLA-4 and anti–PD-1 against experimental and carcinogen-induced tumors suggested that these agents might be well-tolerated and very effective in combination. Cancer Res; 71(10); 3540–51. ©2011 AACR.
Data from Molecular Pathobiology of Human Cervical High-Grade Lesions: Paracrine STAT3 Activation in Tumor-Instructed Myeloid Cells Drives Local MMP-9 Expression
Authors: Schröer Nadine , Pahne Jennifer , Walch Barbara , Wickenhauser Claudia , Smola Sigrun
Published: March 2024

Abstract
In many tumors, the switch from precancerous lesions to malignancy critically relies on expression of the matrix-metalloprotease MMP-9, which is predominantly provided by infiltrating inflammatory cells. Our study defines a novel molecular cascade, how human neoplastic cells instruct tumor-associated myeloid cells to produce MMP-9. In biopsies of human papillomavirus–associated precancerous cervical intraepithelial neoplasia (CIN III lesions), we show broad activation of the transcription factor STAT3 and coexpression of MMP-9 in perivascular inflammatory cells. For the first time, we establish a causative link between tumor-mediated paracrine STAT3 activation and MMP-9 production by human tumor-instructed monocytes, whereas NF-κB activation is dispensable for this response. Our data provide evidence that STAT3 does not directly induce MMP-9 but first leads to a strong production of the monocyte chemoattractant protein-1 (CCL2) in the nanogram range. In a second phase, autocrine stimulation of the CCR2 receptor in the tumor-instructed monocytes amplifies MMP-9 expression via intracellular Ca2+ signaling. These findings elucidate a critical mechanism in the molecular pathobiology of cervical carcinogenesis at the switch to malignancy. Particularly in tumors, which are associated with infectious agents, STAT3-driven inflammation may be pivotal to promote carcinogenesis, while at the same time limit NF-κB–dependent immune responses and thus rejection of the infected preneoplastic cells. The molecular cascade defined in this study provides the basis for a rational design of future adjuvant therapies of cervical precancerous lesions. Cancer Res; 71(1); 87–97. ©2011 AACR. Cancer Res; 71(1); 87–97. ©2011 AACR.
Data from Suppression of Apoptosis by PIF1 Helicase in Human Tumor Cells
Authors: Gagou Mary E. , Ganesh Anil , Thompson Ruth , Phear Geraldine , Sanders Cyril , Meuth Mark
Published: March 2024

Abstract
Defining the processes that sustain telomere maintenance is critical to our understanding of cancer and longevity. PIF1 is a nonprocessive 5′->3′ human DNA helicase that exhibits broad substrate specificity. In vitro studies have implicated PIF1 in maintaining telomeres and processing stalled DNA replication forks, but disruption of the murine Pif1 gene did not yield any apparent phenotype. In this study, we evaluated the function of the PIF1 gene in human cells by using siRNA knockdown strategies to gauge its role in the response to DNA replication stress. We found that PIF1 depletion reduced the survival of both p53-deficient and p53-proficient human tumor cells by triggering apoptosis. In contrast, nonmalignant cells were unaffected by PIF1 depletion. Apoptosis induction in tumor cells was augmented by cotreatment with replication inhibitors (thymidine, hydroxyurea, or gemcitabine). When sensitive PIF1-depleted cells were released from a thymidine-induced S-phase arrest, there remained a subpopulation of cells that failed to enter S-phase. This cell subpopulation displayed an increase in levels of cyclin E and p21, as well as a deficiency in S-phase checkpoint markers that were induced with thymidine in PIF1 expressing cells. Specifically, CHK1 activation was suppressed and we detected no consistent changes in ATM S1981 autophosphorylation, γH2AX induction, or RPA hyperphosphorylation. Death in PIF1-depleted cells was detected in late G1/early S-phase and was dependent on caspase-3 activity. Taken together, our findings suggest roles for PIF1 in S-phase entry and progression that are essential to protect human tumor cells from apoptosis. Cancer Res; 71(14); 4998–5008. ©2011 AACR.
Data from Estrogen-Dependent Gene Transcription in Human Breast Cancer Cells Relies upon Proteasome-Dependent Monoubiquitination of Histone H2B
Authors: Prenzel Tanja , Begus-Nahrmann Yvonne , Kramer Frank , Hennion Magali , Hsu Chieh , Gorsler Theresa , Hintermair Corinna , Eick Dirk , Kremmer Elisabeth , Simons Mikael , Beissbarth Tim , Johnsen Steven A.
Published: March 2024

Abstract
The estrogen receptor-α (ERα) determines the phenotype of breast cancers where it serves as a positive prognostic indicator. ERα is a well-established target for breast cancer therapy, but strategies to target its function remain of interest to address therapeutic resistance and further improve treatment. Recent findings indicate that proteasome inhibition can regulate estrogen-induced transcription, but how ERα function might be regulated was uncertain. In this study, we investigated the transcriptome-wide effects of the proteasome inhibitor bortezomib on estrogen-regulated transcription in MCF7 human breast cancer cells and showed that bortezomib caused a specific global decrease in estrogen-induced gene expression. This effect was specific because gene expression induced by the glucocorticoid receptor was unaffected by bortezomib. Surprisingly, we observed no changes in ERα recruitment or assembly of its transcriptional activation complex on ERα target genes. Instead, we found that proteasome inhibition caused a global decrease in histone H2B monoubiquitination (H2Bub1), leading to transcriptional elongation defects on estrogen target genes and to decreased chromatin dynamics overall. In confirming the functional significance of this link, we showed that RNA interference–mediated knockdown of the H2B ubiquitin ligase RNF40 decreased ERα-induced gene transcription. Surprisingly, RNF40 knockdown also supported estrogen-independent cell proliferation and activation of cell survival signaling pathways. Most importantly, we found that H2Bub1 levels decrease during tumor progression. H2Bub1 was abundant in normal mammary epithelium and benign breast tumors but absent in most malignant and metastatic breast cancers. Taken together, our findings show how ERα activity is blunted by bortezomib treatment as a result of reducing the downstream ubiquitin-dependent function of H2Bub1. In supporting a tumor suppressor role for H2Bub1 in breast cancer, our findings offer a rational basis to pursue H2Bub1-based therapies for future management of breast cancer. Cancer Res; 71(17); 5739–53. ©2011 AACR.
Data from MicroRNA Sequence and Expression Analysis in Breast Tumors by Deep Sequencing
Authors: Farazi Thalia A. , Horlings Hugo M. , ten Hoeve Jelle J. , Mihailovic Aleksandra , Halfwerk Hans , Morozov Pavel , Brown Miguel , Hafner Markus , Reyal Fabien , van Kouwenhove Marieke , Kreike Bas , Sie Daoud , Hovestadt Volker , Wessels Lodewyk F.A. , van de Vijver Marc J. , Tuschl Thomas
Published: March 2024

Abstract
MicroRNAs (miRNA) regulate many genes critical for tumorigenesis. We profiled miRNAs from 11 normal breast tissues, 17 noninvasive, 151 invasive breast carcinomas, and 6 cell lines by in-house–developed barcoded Solexa sequencing. miRNAs were organized in genomic clusters representing promoter-controlled miRNA expression and sequence families representing seed sequence–dependent miRNA target regulation. Unsupervised clustering of samples by miRNA sequence families best reflected the clustering based on mRNA expression available for this sample set. Clustering and comparative analysis of miRNA read frequencies showed that normal breast samples were separated from most noninvasive ductal carcinoma in situ and invasive carcinomas by increased miR-21 (the most abundant miRNA in carcinomas) and multiple decreased miRNA families (including miR-98/let-7), with most miRNA changes apparent already in the noninvasive carcinomas. In addition, patients that went on to develop metastasis showed increased expression of mir-423, and triple-negative breast carcinomas were most distinct from other tumor subtypes due to upregulation of the mir∼17–92 cluster. However, absolute miRNA levels between normal breast and carcinomas did not reveal any significant differences. We also discovered two polymorphic nucleotide variations among the more abundant miRNAs miR-181a (T19G) and miR-185 (T16G), but we did not identify nucleotide variations expected for classical tumor suppressor function associated with miRNAs. The differentiation of tumor subtypes and prediction of metastasis based on miRNA levels is statistically possible but is not driven by deregulation of abundant miRNAs, implicating far fewer miRNAs in tumorigenic processes than previously suggested. Cancer Res; 71(13); 4443–53. ©2011 AACR.
Data from Src Activation Plays an Important Key Role in Lymphomagenesis Induced by FGFR1 Fusion Kinases
Authors: Ren Mingqiang , Qin Haiyan , Ren Ruizhe , Tidwell Josephine , Cowell John K.
Published: March 2024

Abstract
Chromosomal translocations and activation of the fibroblast growth factor (FGF) receptor 1 (FGFR1) are a feature of stem cell leukemia–lymphoma syndrome (SCLL), an aggressive malignancy characterized by rapid transformation to acute myeloid leukemia and lymphoblastic lymphoma. It has been suggested that FGFR1 proteins lose their ability to recruit Src kinase, an important mediator of FGFR1 signaling, as a result of the translocations that delete the extended FGFR substrate-2 (FRS2) interacting domain that Src binds. In this study, we report evidence that refutes this hypothesis and reinforces the notion that Src is a critical mediator of signaling from the FGFR1 chimeric fusion genes generated by translocation in SCLL. Src was constitutively active in BaF3 cells expressing exogenous FGFR1 chimeric kinases cultured in vitro as well as in T-cell or B-cell lymphomas they induced in vivo. Residual components of the FRS2-binding site retained in chimeric kinases that were generated by translocation were sufficient to interact with FRS2 and activate Src. The Src kinase inhibitor dasatinib killed transformed BaF3 cells and other established murine leukemia cell lines expressing chimeric FGFR1 kinases, significantly extending the survival of mice with SCLL syndrome. Our results indicated that Src kinase is pathogenically activated in lymphomagenesis induced by FGFR1 fusion genes, implying that Src kinase inhibitors may offer a useful option to treatment of FGFR1-associated myeloproliferative/lymphoma disorders. Cancer Res; 71(23); 7312–22. ©2011 AACR.
Data from Glioblastoma-Derived Epidermal Growth Factor Receptor Carboxyl-Terminal Deletion Mutants Are Transforming and Are Sensitive to EGFR-Directed Therapies
Authors: Cho Jeonghee , Pastorino Sandra , Zeng Qing , Xu Xiaoyin , Johnson William , Vandenberg Scott , Verhaak Roel , Cherniack Andrew D. , Watanabe Hideo , Dutt Amit , Kwon Jihyun , Chao Ying S. , Onofrio Robert C. , Chiang Derek , Yuza Yuki , Kesari Santosh , Meyerson Matthew
Published: March 2024

Abstract
Genomic alterations of the epidermal growth factor receptor (EGFR) gene play a crucial role in pathogenesis of glioblastoma multiforme (GBM). By systematic analysis of GBM genomic data, we have identified and characterized a novel exon 27 deletion mutation occurring within the EGFR carboxyl-terminus domain (CTD), in addition to identifying additional examples of previously reported deletion mutations in this region. We show that the GBM-derived EGFR CTD deletion mutants are able to induce cellular transformation in vitro and in vivo in the absence of ligand and receptor autophosphorylation. Treatment with the EGFR-targeted monoclonal antibody, cetuximab, or the small molecule EGFR inhibitor, erlotinib, effectively impaired tumorigenicity of oncogenic EGFR CTD deletion mutants. Cetuximab in particular prolonged the survival of intracranially xenografted mice with oncogenic EGFR CTD deletion mutants, compared with untreated control mice. Therefore, we propose that erlotinib and, especially, cetuximab treatment may be a promising therapeutic strategy in GBM patients harboring EGFR CTD deletion mutants. Cancer Res; 71(24); 7587–96. ©2011 AACR.
Data from Enhanced Efficacy of Therapeutic Cancer Vaccines Produced by Co-Treatment with Mycobacterium tuberculosis Heparin-Binding Hemagglutinin, a Novel TLR4 Agonist
Authors: Jung In Duk , Jeong Soo Kyung , Lee Chang-Min , Noh Kyung Tae , Heo Deok Rim , Shin Yong Kyoo , Yun Cheol-Heui , Koh Won-Jung , Akira Shizuo , Whang Jake , Kim Hwa-Jung , Park Won Sun , Shin Sung Jae , Park Yeong-Min
Published: March 2024

Abstract
Effective activation of dendritic cells (DCs) toward T helper (Th)-1 cell polarization would improve DC-based antitumor immunotherapy, helping promote the development of immunotherapeutic vaccines based on T-cell immunity. To achieve this goal, it is essential to develop effective immune adjuvants that can induce powerful Th1 cell immune responses. The pathogenic organism Mycobacterium tuberculosis includes certain constitutes, such as heparin-binding hemagglutinin (HBHA), that possess a strong immunostimulatory potential. In this study, we report the first clarification of the functions and precise mechanism of HBHA in immune stimulation settings relevant to cancer. HBHA induced DC maturation in a TLR4-dependent manner, elevating expression of the surface molecules CD40, CD80, and CD86, MHC classes I and II and the proinflammatory cytokines IL-6, IL-12, IL-1β, TNF-α, and CCR7, as well as stimulating the migratory capacity of DCs in vitro and in vivo. Mechanistic investigations established that MyD88 and TRIF signaling pathways downstream of TLR4 mediated secretion of HBHA-induced proinflammatory cytokines. HBHA-treated DCs activated naïve T cells, polarized CD4+ and CD8+ T cells to secrete IFN-γ, and induced T-cell–mediated cytotoxicity. Notably, systemic administration of DCs that were HBHA-treated and OVA251–264-pulsed ex vivo greatly strengthened immune priming in vivo, inducing a dramatic regression of tumor growth associated with long-term survival in a murine E.G7 thymoma model. Together, our findings highlight HBHA as an immune adjuvant that favors Th1 polarization and DC function for potential applications in DC-based antitumor immunotherapy. Cancer Res; 71(8); 2858–70. ©2011 AACR.
Data from Stromal Deletion of the APC Tumor Suppressor in Mice Triggers Development of Endometrial Cancer
Authors: Tanwar Pradeep S. , Zhang LiHua , Roberts Drucilla J. , Teixeira Jose M.
Published: March 2024

Abstract
The contribution of the stromal microenvironment to the progression of endometrial cancer has not been well explored. We have conditionally expressed a mutant allele of adenomatous polyposis coli (APCcKO) in murine uterine stroma cells to study its effect on uterine development and function. In addition to metrorrhagia, the mice develop complex atypical endometrial gland hyperplasia that progresses to endometrial carcinoma in situ and endometrial adenocarcinoma as evidenced by myometrial invasion. Stromal cells subjacent to the carcinoma cells express alpha-smooth muscle actin (αSMA) with fewer cells expressing platelet-derived growth factor α compared with normal stromal cells, suggesting that the mutant stromal cells have acquired a more myofibroblastic phenotype, which have been described as cancer-associated fibroblasts and have been shown to induce carcinogenesis in other organ systems. Analyses of human endometrial cancer specimens showed substantial αSMA expression in the stroma compared with normal endometrial stroma cells. We also show that APCcKO mutant uteri and human endometrial cancer have decreased stromal levels of transforming growth factor β and bone morphogenetic protein activities and that the mutant uteri failed to respond to exogenous estradiol stimulation. The mutant stroma cells also had higher levels of vascular endothelial growth factor and stromal derived factor signaling components and diminished expression of estrogen receptor α and progesterone receptor, which is common in advanced stages of human endometrial cancer and is an indicator of poor prognosis. Our results indicate that de novo mutation or loss of heterozygosity in stromal APC is sufficient to induce endometrial hyperplasia and endometrial carcinogenesis by mechanisms that are consistent with unopposed estrogen signaling in the endometrial epithelium. Cancer Res; 71(5); 1584–96. ©2011 AACR.
Data from Genetic Ablation of SOX18 Function Suppresses Tumor Lymphangiogenesis and Metastasis of Melanoma in Mice
Authors: Duong Tam , Proulx Steven T. , Luciani Paola , Leroux Jean-Christophe , Detmar Michael , Koopman Peter , Francois Mathias
Published: March 2024

Abstract
The lymphatic vasculature provides a major route for tumor metastasis and inhibiting neolymphangiogenesis induced by tumors can reduce metastasis in animal models. Developmental biology studies have identified the transcription factor SOX18 as a critical switch for lymphangiogenesis in the mouse embryo. Here, we show that SOX18 is also critical for tumor-induced lymphangiogenesis, and we show that suppressing SOX18 function is sufficient to impede tumor metastasis. Immunofluorescence analysis of murine tumor xenografts showed that SOX18 is reexpressed during tumor-induced neolymphangiogenesis. Tumors generated by implantation of firefly luciferase-expressing B16-F10 melanoma cells exhibited a reduced rate of metastasis to the regional draining lymph node in Sox18-deficient mice, as assessed by live bioluminescence imaging. Lower metastatic rates correlated with reduced tumoral lymphatic vessel density and diameter and with impaired drainage of peritumoral injected liposomes specific for lymph vessels from the sentinel lymph nodes. Overall, our findings suggested that SOX18 induction is a key step in mediating tumor lymphangiogenesis and metastasis, and they identify SOX18 as a potential therapeutic target for metastatic blockade. Cancer Res; 72(12); 3105–14. ©2012 AACR.
Data from HERC2 Interacts with Claspin and Regulates DNA Origin Firing and Replication Fork Progression
Authors: Izawa Naoki , Wu Wenwen , Sato Ko , Nishikawa Hiroyuki , Kato Akihiro , Boku Narikazu , Itoh Fumio , Ohta Tomohiko
Published: March 2024

Abstract
DNA replication, recombination, and repair are highly interconnected processes the disruption of which must be coordinated in cancer. HERC2, a large HECT protein required for homologous recombination repair, is an E3 ubiquitin ligase that targets breast cancer suppressor BRCA1 for degradation. Here, we show that HERC2 is a component of the DNA replication fork complex that plays a critical role in DNA elongation and origin firing. In the presence of BRCA1, endogenous HERC2 interacts with Claspin, a protein essential for G2–M checkpoint activation and replication fork stability. Claspin depletion slowed S-phase progression and additional HERC2 depletion reduced the effect of Claspin depletion. In addition, HERC2 interacts with replication fork complex proteins. Depletion of HERC2 alleviated the slow replication fork progression in Claspin-deficient cells, suppressed enhanced origin firing, and led to a decrease in MCM2 phosphorylation. In a HERC2-dependent manner, treatment of cells with replication inhibitor aphidicolin enhanced MCM2 phosphorylation. Taken together, our results suggest that HERC2 regulates DNA replication progression and origin firing by facilitating MCM2 phosphorylation. These findings establish HERC2 as a critical function in DNA repair, checkpoint activation, and DNA replication. Cancer Res; 71(17); 5621–5. ©2011 AACR.
Data from E-3810 Is a Potent Dual Inhibitor of VEGFR and FGFR that Exerts Antitumor Activity in Multiple Preclinical Models
Authors: Bello Ezia , Colella Gennaro , Scarlato Valentina , Oliva Paolo , Berndt Alexander , Valbusa Giovanni , Serra Sonia Colombo , D'Incalci Maurizio , Cavalletti Ennio , Giavazzi Raffaella , Damia Giovanna , Camboni Gabriella
Published: March 2024

Abstract
Tumor angiogenesis is a degenerate process regulated by a complex network of proangiogenic factors. Existing antiangiogenic drugs used in clinic are characterized by selectivity for specific factors. Antiangiogenic properties might be improved in drugs that target multiple factors and thereby address the inherent mechanistic degeneracy in angiogenesis. Vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) family members and their cognate receptors are key players in promoting tumor angiogenesis. Here we report the pharmacologic profile of E-3810, a novel dual inhibitor of the VEGF and FGF receptors. E-3810 potently and selectively inhibited VEGF receptor (VEGFR)-1, -2, and -3 and FGF receptor (FGFR)-1 and -2 kinases in the nanomolar range. Ligand-dependent phosphorylation of VEGFR-2 and FGFR-1 was suppressed along with human vascular endothelial cell growth at nanomolar concentrations. In contrast, E-3810 lacked cytotoxic effects on cancer cell lines under millimolar concentrations. In a variety of tumor xenograft models, including early- or late-stage subcutaneous and orthotopic models, E-3810 exhibited striking antitumor properties at well-tolerated oral doses administered daily. We found that E-3810 remained active in tumors rendered nonresponsive to the general kinase inhibitor sunitinib resulting from a previous cycle of sunitinib treatment. In Matrigel plug assays performed in nude mice, E-3810 inhibited basic FGF–induced angiogenesis and reduced blood vessel density as assessed by histologic analysis. Dynamic contrast-enhanced magnetic resonance imaging analysis confirmed that E-3810 reduced the distribution of angiogenesis-sensitive contrast agents after only 5 days of treatment. Taken together, our findings identify E-3810 as a potent antiangiogenic small molecule with a favorable pharmacokinetic profile and broad spectrum antitumor activity, providing a strong rationale for its clinical evaluation. Cancer Res; 71(4); 1396–405. ©2011 AACR.
Data from A Mammaglobin-A Targeting Agent for Noninvasive Detection of Breast Cancer Metastasis in Lymph Nodes
Authors: Tafreshi Narges K. , Enkemann Steven A. , Bui Marilyn M. , Lloyd Mark C. , Abrahams Dominique , Huynh Amanda S. , Kim Jongphil , Grobmyer Stephen R. , Carter W. Bradford , Vagner Josef , Gillies Robert J. , Morse David L.
Published: March 2024

Abstract
Pathologic axillary lymph node (ALN) status is an important prognostic factor for staging breast cancer. Currently, status is determined by histopathology following surgical excision of sentinel lymph node(s), which is an invasive, time consuming, and costly procedure with potential morbidity to the patient. Here, we describe an imaging platform for noninvasive assessment of ALN status, eliminating the need for surgical examination of patients to rule out nodal involvement. A targeted imaging probe (MamAb-680) was developed by conjugation of a mammaglobin-A–specific monoclonal antibody to a near-infrared fluorescent dye. Using DNA and tissue microarray, mammaglobin-A was validated as a cell-surface target that is expressed in ALN-positive patient samples but is not expressed in normal lymph nodes. In vivo selectivity was determined by i.v. injection of MamAb-680 into mice with mammaglobin-A–positive and -negative mammary fat pad (MFP) tumors; and by peritumoral MFP injection of the targeted imaging probe in mice with spontaneous ALN metastases. Fluorescence imaging showed that probe was only retained in positive tumors and metastases. As few as 1,000 cells that endogenously express mammaglobin-A were detected in ALN, indicating high sensitivity of this method. Translation of this approach offers considerable potential as a noninvasive clinical strategy to stage breast cancer. Cancer Res; 71(3); 1050–9. ©2010 AACR.
Data from Overcoming Temozolomide Resistance in Glioblastoma via Dual Inhibition of NAD+ Biosynthesis and Base Excision Repair
Authors: Goellner Eva M. , Grimme Bradford , Brown Ashley R. , Lin Ying-Chih , Wang Xiao-Hong , Sugrue Kelsey F. , Mitchell Leah , Trivedi Ram N. , Tang Jiang-bo , Sobol Robert W.
Published: March 2024

Abstract
Glioblastoma multiforme (GBM) is a devastating brain tumor with poor prognosis and low median survival time. Standard treatment includes radiation and chemotherapy with the DNA alkylating agent temozolomide (TMZ). However, a large percentage of tumors are resistant to the cytotoxic effects of the TMZ-induced DNA lesion O6-methylguanine due to elevated expression of the repair protein O6-methylguanine-DNA methyltransferase (MGMT) or a defect in the mismatch repair (MMR) pathway. Although a majority of the TMZ-induced lesions (N7-methylguanine and N3-methyladenine) are base excision repair (BER) substrates, these DNA lesions are also readily repaired. However, blocking BER can enhance response to TMZ and therefore the BER pathway has emerged as an attractive target for reversing TMZ resistance. Our lab has recently reported that inhibition of BER leads to the accumulation of repair intermediates that induce energy depletion–mediated cell death via hyperactivation of poly(ADP-ribose) polymerase. On the basis of our observation that TMZ-induced cell death via BER inhibition is dependent on the availability of nicotinamide adenine dinucleotide (NAD+), we have hypothesized that combined BER and NAD+ biosynthesis inhibition will increase TMZ efficacy in glioblastoma cell lines greater than BER inhibition alone. Importantly, we find that the combination of BER and NAD+ biosynthesis inhibition significantly sensitizes glioma cells with elevated expression of MGMT and those deficient in MMR, two genotypes normally associated with TMZ resistance. Dual targeting of these two interacting pathways (DNA repair and NAD+ biosynthesis) may prove to be an effective treatment combination for patients with resistant and recurrent GBM. Cancer Res; 71(6); 2308–17. ©2011 AACR.
Data from Raf Kinase Inhibitor Protein RKIP Enhances Signaling by Glycogen Synthase Kinase-3β
Authors: Al-Mulla Fahd , Bitar Milad S. , Al-Maghrebi May , Behbehani Abdulla I. , Al-Ali Waleed , Rath Oliver , Doyle Brendan , Tan Kit Yee , Pitt Andrew , Kolch Walter
Published: March 2024

Abstract
Raf kinase inhibitory protein (RKIP) is a physiologic inhibitor of c-RAF kinase and nuclear factor κB signaling that represses tumor invasion and metastasis. Glycogen synthase kinase-3β (GSK3β) suppresses tumor progression by downregulating multiple oncogenic pathways including Wnt signaling and cyclin D1 activation. Here, we show that RKIP binds GSK3 proteins and maintains GSK3β protein levels and its active form. Depletion of RKIP augments oxidative stress–mediated activation of the p38 mitogen activated protein kinase, which, in turn, inactivates GSK3β by phosphorylating it at the inhibitory T390 residue. This pathway de-represses GSK3β inhibition of oncogenic substrates causing stabilization of cyclin D, which induces cell-cycle progression and β-catenin, SNAIL, and SLUG, which promote epithelial to mesenchymal transition. RKIP levels in human colorectal cancer positively correlate with GSK3β expression. These findings reveal the RKIP/GSK3 axis as both a potential therapeutic target and a prognosis-based predictor of cancer progression. Cancer Res; 71(4); 1334–43. ©2011 AACR.
Data from Selectin Ligand Sialyl-Lewis x Antigen Drives Metastasis of Hormone-Dependent Breast Cancers
Authors: Julien Sylvain , Ivetic Aleksandar , Grigoriadis Anita , QiZe Ding , Burford Brian , Sproviero Daisy , Picco Gianfranco , Gillett Cheryl , Papp Suzanne L. , Schaffer Lana , Tutt Andrew , Taylor-Papadimitriou Joyce , Pinder Sarah E. , Burchell Joy M.
Published: March 2024

Abstract
The glycome acts as an essential interface between cells and the surrounding microenvironment. However, changes in glycosylation occur in nearly all breast cancers, which can alter this interaction. Here, we report that profiles of glycosylation vary between ER-positive and ER-negative breast cancers. We found that genes involved in the synthesis of sialyl-Lewis x (sLex; FUT3, FUT4, and ST3GAL6) are significantly increased in estrogen receptor alpha-negative (ER-negative) tumors compared with ER-positive ones. SLex expression had no influence on the survival of patients whether they had ER-negative or ER-positive tumors. However, high expression of sLex in ER-positive tumors was correlated with metastasis to the bone where sLex receptor E-selectin is constitutively expressed. The ER-positive ZR-75-1 and the ER-negative BT20 cell lines both express sLex but only ZR-75-1 cells could adhere to activated endothelial cells under dynamic flow conditions in a sLex and E-selectin–dependent manner. Moreover, L/P-selectins bound strongly to ER-negative MDA-MB-231 and BT-20 cell lines in a heparan sulfate (HS)–dependent manner that was independent of sLex expression. Expression of glycosylation genes involved in heparan biosynthesis (EXT1 and HS3ST1) was increased in ER-negative tumors. Taken together, our results suggest that the context of sLex expression is important in determining its functional significance and that selectins may promote metastasis in breast cancer through protein-associated sLex and HS glycosaminoglycans. Cancer Res; 71(24); 7683–93. ©2011 AACR.
Data from Myc Posttranscriptionally Induces HIF1 Protein and Target Gene Expression in Normal and Cancer Cells
Authors: Doe Megan R. , Ascano Janice M. , Kaur Mandeep , Cole Michael D.
Published: March 2024

Abstract
c-Myc is frequently overexpressed in tumors and plays an important role in the regulation of cancer metabolism. Hypoxia-inducible factor-1 (HIF1), the master regulator of the hypoxic response, enhances tumorigenesis and influences metabolism via upregulation of the glycolytic pathway and suppression of mitochondrial respiration. Together, deregulated Myc and HIF1 cooperate to lend metabolic advantages to proliferating cancer cells and contribute to the Warburg effect. Here we show that overexpression of Myc significantly stabilizes the α subunit of HIF1 (HIF1α) under normoxic conditions and enhances HIF1α accumulation under hypoxic conditions in cells. Posttranscriptional regulation of HIF1α by Myc led to the induction of HIF1α gene targets. Normoxic HIF1α protein expression was also dependent on Myc. Functionally, HIF1α expression was required for Myc-induced anchorage-independent growth and cell proliferation. Myc-dependent stabilization of HIF1α involved either disruption of binding to the VHL complex or posttranslational protein modifications. Taken together, our findings uncover a previously uncharacterized regulatory relationship between Myc and HIF1 that has important implications for cancer metabolism and development. Cancer Res; 72(4); 949–57. ©2011 AACR.
Data from RALBP1/RLIP76 Depletion in Mice Suppresses Tumor Growth by Inhibiting Tumor Neovascularization
Authors: Lee Seunghyung , Wurtzel Jeremy G. T. , Singhal Sharad S. , Awasthi Sanjay , Goldfinger Lawrence E.
Published: March 2024

Abstract
RalBP1/RLIP76 is a widely expressed multifunctional protein that binds the Ral and R-Ras small GTPases. In the mouse, RLIP76 is nonessential but its depletion or blockade promotes tumorigenesis and heightens the sensitivity of normal and tumor cells to radiation and cytotoxic drugs. However, its pathobiologic functions, which support tumorigenesis, are not well understood. Here, we show that RLIP76 is required for angiogenesis and for efficient neovascularization of primary solid tumors. Tumor growth from implanted melanoma or carcinoma cells was blunted in RLIP76−/− mice. An X-ray microcomputed tomography-based method to model tumor vascular structures revealed defects in both the extent and form of tumor angiogenesis in RLIP76−/− mice. Specifically, tumor vascular volumes were diminished and vessels were fewer in number, shorter, and narrower in RLIP76−/− mice than in wild-type mice. Moreover, we found that angiogenesis was blunted in mutant mice in the absence of tumor cells, with endothelial cells isolated from these animals exhibiting defects in migration, proliferation, and cord formation in vitro. Taken together, our results establish that RLIP76 is required for efficient endothelial cell function and angiogenesis in solid tumors. Cancer Res; 72(20); 5165–73. ©2012 AACR.
Data from Dual Inhibition of the PI3K/mTOR Pathway Increases Tumor Radiosensitivity by Normalizing Tumor Vasculature
Authors: Fokas Emmanouil , Im Jae Hong , Hill Sally , Yameen Sabira , Stratford Michael , Beech John , Hackl Wolfgang , Maira Sauveur-Michel , Bernhard Eric J. , McKenna W. Gillies , Muschel Ruth J.
Published: March 2024

Abstract
The aberrant vascular architecture of solid tumors results in hypoxia that limits the efficacy of radiotherapy. Vascular normalization using antiangiogenic agents has been proposed as a means to improve radiation therapy by enhancing tumor oxygenation, but only short-lived effects for this strategy have been reported so far. Here, we show that NVP-BEZ235, a dual inhibitor of phosphoinositide-3-kinase (PI3K) and mTOR, can improve tumor oxygenation and vascular structure over a prolonged period that achieves the aim of effective vascular normalization. Because PI3K inhibition can radiosensitize tumor cells themselves, our experimental design explicitly distinguished effects on the blood vasculature versus tumor cells. Drug administration coincident with radiation enhanced the delay in tumor growth without changing tumor oxygenation, establishing that radiosensitization is a component of the response. However, the enhanced growth delay was substantially greater after induction of vascular normalization, meaning that this treatment enhanced the tumoral radioresponse. Importantly, changes in vascular morphology persisted throughout the entire course of the experiment. Our findings indicated that targeting the PI3K/mTOR pathway can modulate the tumor microenvironment to induce a prolonged normalization of blood vessels. The substantial therapeutic gain observed after combination of NVP-BEZ235 with irradiation has conceptual implications for cancer therapy and could be of broad translational importance. Cancer Res; 72(1); 239–48. ©2011 AACR.