bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Mechanical Stiffness Grades Metastatic Potential in Patient Tumor Cells and in Cancer Cell Lines
Authors: Swaminathan Vinay , Mythreye Karthikeyan , O'Brien E. Tim , Berchuck Andrew , Blobe Gerard C. , Superfine Richard
Published: March 2024

Abstract
Cancer cells are defined by their ability to invade through the basement membrane, a critical step during metastasis. While increased secretion of proteases, which facilitates degradation of the basement membrane, and alterations in the cytoskeletal architecture of cancer cells have been previously studied, the contribution of the mechanical properties of cells in invasion is unclear. Here, we applied a magnetic tweezer system to establish that stiffness of patient tumor cells and cancer cell lines inversely correlates with migration and invasion through three-dimensional basement membranes, a correlation known as a power law. We found that cancer cells with the highest migratory and invasive potential are five times less stiff than cells with the lowest migration and invasion potential. Moreover, decreasing cell stiffness by pharmacologic inhibition of myosin II increases invasiveness, whereas increasing cell stiffness by restoring expression of the metastasis suppressor TβRIII/betaglycan decreases invasiveness. These findings are the first demonstration of the power-law relation between the stiffness and the invasiveness of cancer cells and show that mechanical phenotypes can be used to grade the metastatic potential of cell populations with the potential for single cell grading. The measurement of a mechanical phenotype, taking minutes rather than hours needed for invasion assays, is promising as a quantitative diagnostic method and as a discovery tool for therapeutics. By showing that altering stiffness predictably alters invasiveness, our results indicate that pathways regulating these mechanical phenotypes are novel targets for molecular therapy of cancer. Cancer Res; 71(15); 5075–80. ©2011 AACR.
Data from Angiopoietin-like Protein 2 Is an Important Facilitator of Inflammatory Carcinogenesis and Metastasis
Authors: Aoi Jun , Endo Motoyoshi , Kadomatsu Tsuyoshi , Miyata Keishi , Nakano Masahiro , Horiguchi Haruki , Ogata Aki , Odagiri Haruki , Yano Masato , Araki Kimi , Jinnin Masatoshi , Ito Takaaki , Hirakawa Satoshi , Ihn Hironobu , Oike Yuichi
Published: March 2024

Abstract
Chronic inflammation plays important roles at different stages of cancer development, including carcinogenesis, tumor invasion, and metastasis, but molecular mechanisms linking inflammation to cancer development have not been fully clarified. Here, we report that expression of angiopoietin-like protein 2 (Angptl2), recently identified as a chronic inflammation mediator, is highly correlated with the frequency of carcinogenesis in a chemically induced skin squamous cell carcinoma (SCC) mouse model. Furthermore, Angptl2 expression in SCC is highly correlated with the frequency of tumor cell metastasis to distant secondary organs and lymph nodes. When SCC was induced in transgenic mice expressing Angptl2 in skin epithelial cells, epithelial-to-mesenchymal transitions in SCC as well as tumor angiogenesis and lymphangiogenesis were significantly increased, resulting in increased tumor cell metastasis and shortened survival compared with wild-type mice. Conversely, in a chemically induced SCC mouse model, carcinogenesis and metastasis were markedly attenuated in Angptl2 knockout mice, resulting in extended survival compared with wild-type mice. Overall, we propose that Angptl2 contributes to increased carcinogenesis and metastasis and represents a novel target to antagonize these pathologies. Cancer Res; 71(24); 7502–12. ©2011 AACR.
Data from p53 Binds to and Is Required for the Repression of Arf Tumor Suppressor by HDAC and Polycomb
Authors: Zeng Yaxue , Kotake Yojiro , Pei Xin-Hai , Smith Matthew D. , Xiong Yue
Published: March 2024

Abstract
The expression of tumor suppressor Arf is tightly repressed during normal cell growth at a young age and is activated by oncogenic insults, and during aging, results in p53 activation and cell-cycle arrest to prevent hyperproliferation. The mechanisms of both transcriptional repression and activation of Arf are not understood. We show that p53 binds to and represses Arf expression and that this repression requires the function of both histone deacetylases (HDAC) and polycomb group (PcG) proteins. Inactivation of p53 leads to increased Arf transcription in both mouse embryonic fibroblasts (MEF) cultured in vitro and in tissues and organs of p53 null mice. Activation of endogenous p53 enhances Arf repression, and reintroduction of p53 back into p53 null MEFs restores Arf repression. Both DNA binding and transactivation activities of p53 are required for Arf repression. We show that p53 is required for both HDAC and PcG to repress Arf expression. Bindings of both HDAC and PcG to Arf are disrupted by inactivation of p53 and can be restored in p53 null MEFs by the reintroduction of wild-type, but not mutant, p53. These results indicate that p53 recruits both HDAC and PcG to Arf locus to repress its expression, and this repression constitutes a second feedback loop in p53 regulation. Cancer Res; 71(7); 2781–92. ©2011 AACR.
Data from Fes Tyrosine Kinase Expression in the Tumor Niche Correlates with Enhanced Tumor Growth, Angiogenesis, Circulating Tumor Cells, Metastasis, and Infiltrating Macrophages
Authors: Zhang Shengnan , Chitu Violeta , Stanley E. Richard , Elliott Bruce E. , Greer Peter A.
Published: March 2024

Abstract
Fes is a protein tyrosine kinase with cell autonomous oncogenic activities that are well established in cell culture and animal models, but its involvement in human cancer has been unclear. Abundant expression of Fes in vascular endothelial cells and myeloid cell lineages prompted us to explore roles for Fes in the tumor microenvironment. In an orthotopic mouse model of breast cancer, we found that loss of Fes in the host correlated with reductions in engrafted tumor growth rates, metastasis, and circulating tumor cells. The tumor microenvironment in Fes-deficient mice also showed reduced vascularity and fewer macrophages. In co-culture with tumor cells, Fes-deficient macrophages also poorly promoted tumor cell invasive behavior. Taken together, our observations argue that Fes inhibition might provide therapeutic benefits in breast cancer, in part by attenuating tumor-associated angiogenesis and the metastasis-promoting functions of tumor-associated macrophages. Cancer Res; 71(4); 1465–73. ©2010 AACR.
Data from Sildenafil Reverses ABCB1- and ABCG2-Mediated Chemotherapeutic Drug Resistance
Authors: Shi Zhi , Tiwari Amit K. , Shukla Suneet , Robey Robert W. , Singh Satyakam , Kim In-Wha , Bates Susan E. , Peng Xingxiang , Abraham Ioana , Ambudkar Suresh V. , Talele Tanaji T. , Fu Li-Wu , Chen Zhe-Sheng
Published: March 2024

Abstract
Sildenafil is a potent and selective inhibitor of the type 5 cGMP (cyclic guanosine 3′,5′-monophosphate)-specific phosphodiesterase that is used clinically to treat erectile dysfunction and pulmonary arterial hypertension. Here, we report that sildenafil has differential effects on cell surface ABC transporters such as ABCB1, ABCC1, and ABCG2 that modulate intracompartmental and intracellular concentrations of chemotherapeutic drugs. In ABCB1-overexpressing cells, nontoxic doses of sildenafil inhibited resistance and increased the effective intracellular concentration of ABCB1 substrate drugs such as paclitaxel. Similarly, in ABCG2-overexpressing cells, sildenafil inhibited resistance to ABCG2 substrate anticancer drugs, for example, increasing the effective intracellular concentration of mitoxantrone or the fluorescent compound BODIPY-prazosin. Sildenafil also moderately inhibited the transport of E217βG and methotrexate by the ABCG2 transporter. Mechanistic investigations revealed that sildenafil stimulated ABCB1 ATPase activity and inhibited photolabeling of ABCB1 with [125I]-iodoarylazidoprazosin (IAAP), whereas it only slightly stimulated ABCG2 ATPase activity and inhibited photolabeling of ABCG2 with [125I]-IAAP. In contrast, sildenafil did not alter the sensitivity of parental, ABCB1-, or ABCG2-overexpressing cells to non-ABCB1 and non-ABCG2 substrate drugs, nor did sildenafil affect the function of another ABC drug transporter, ABCC1. Homology modeling predicted the binding conformation of sildenafil within the large cavity of the transmembrane region of ABCB1. Overall, we found that sildenafil inhibits the transporter function of ABCB1 and ABCG2, with a stronger effect on ABCB1. Our findings suggest a possible strategy to enhance the distribution and potentially the activity of anticancer drugs by jointly using a clinically approved drug with known side effects and drug–drug interactions. Cancer Res; 71(8); 3029–41. ©2011 AACR.
Data from A Critical Role for GRP78/BiP in the Tumor Microenvironment for Neovascularization during Tumor Growth and Metastasis
Authors: Dong Dezheng , Stapleton Christopher , Luo Biquan , Xiong Shigang , Ye Wei , Zhang Yi , Jhaveri Niyati , Zhu Genyuan , Ye Risheng , Liu Zhi , Bruhn Kevin W. , Craft Noah , Groshen Susan , Hofman Florence M. , Lee Amy S.
Published: March 2024

Abstract
Glucose-regulated protein 78 (GRP78)/BiP is a multifunctional protein which plays a major role in endoplasmic reticulum (ER) protein processing, protein quality control, maintaining ER homeostasis, and controlling cell signaling and viability. Previously, using a transgene-induced mammary tumor model, we showed that Grp78 heterozygosity impeded cancer growth through suppression of tumor cell proliferation and promotion of apoptosis and the Grp78+/− mice exhibited dramatic reduction (70%) in the microvessel density (MVD) of the endogenous mammary tumors, while having no effect on the MVD of normal organs. This observation suggests that GRP78 may critically regulate the function of the host vasculature within the tumor microenvironment. In this article, we interrogated the role of GRP78 in the tumor microenvironment. In mouse tumor models in which wild-type (WT), syngeneic mammary tumor cells were injected into the host, we showed that Grp78+/− mice suppressed tumor growth and angiogenesis during the early phase but not during the late phase of tumor growth. Growth of metastatic lesions of WT, syngeneic melanoma cells in the Grp78+/− mice was potently suppressed. We created conditional heterozygous knockout of GRP78 in the host endothelial cells and showed severe reduction of tumor angiogenesis and metastatic growth, with minimal effect on normal tissue MVD. Furthermore, knockdown of GRP78 expression in immortalized human endothelial cells showed that GRP78 is a critical mediator of angiogenesis by regulating cell proliferation, survival, and migration. Our findings suggest that concomitant use of current chemotherapeutic agents and novel therapies against GRP78 may offer a powerful dual approach to arrest cancer initiation, progression, and metastasis. Cancer Res; 71(8); 2848–57. ©2011 AACR.
Data from Activation of TYRO3/AXL Tyrosine Kinase Receptors in Thyroid Cancer
Authors: Avilla Elvira , Guarino Valentina , Visciano Carla , Liotti Federica , Svelto Maria , Krishnamoorthy GnanaPrakasam , Franco Renato , Melillo Rosa Marina
Published: March 2024

Abstract
Thyroid cancer is the most common endocrine cancer, but its key oncogenic drivers remain undefined. In this study we identified the TYRO3 and AXL receptor tyrosine kinases as transcriptional targets of the chemokine CXCL12/SDF-1 in CXCR4-expressing thyroid cancer cells. Both receptors were constitutively expressed in thyroid cancer cell lines but not normal thyroid cells. AXL displayed high levels of tyrosine phosphorylation in most cancer cell lines due to constitutive expression of its ligand GAS6. In human thyroid carcinoma specimens, but not in normal thyroid tissues, AXL and GAS6 were often coexpressed. In cell lines expressing both receptors and ligand, blocking each receptor or ligand dramatically affected cell viability and decreased resistance to apoptotic stimuli. Stimulation of GAS6-negative cancer cells with GAS6 increased their proliferation and survival. Similarly, siRNA-mediated silencing of AXL inhibited cancer cell viability, invasiveness, and growth of tumor xenografts in nude mice. Our findings suggest that a TYRO3/AXL-GAS6 autocrine circuit sustains the malignant features of thyroid cancer cells and that targeting the circuit could offer a novel therapeutic approach in this cancer. Cancer Res; 71(5); 1792–804. ©2011 AACR.
Data from Influence of Affinity and Antigen Internalization on the Uptake and Penetration of Anti-HER2 Antibodies in Solid Tumors
Authors: Rudnick Stephen I. , Lou Jianlong , Shaller Calvin C. , Tang Yong , Klein-Szanto Andres J.P. , Weiner Louis M. , Marks James D. , Adams Gregory P.
Published: March 2024

Abstract
Antibody drugs are widely used in cancer therapy, but conditions to maximize tumor penetration and efficacy have yet to be fully elucidated. In this study, we investigated the impact of antibody binding affinity on tumor targeting and penetration with affinity variants that recognize the same epitope. Specifically, we compared four derivatives of the C6.5 monoclonal antibody (mAb), which recognizes the same HER2 epitope (monovalent KD values ranging from 270 to 0.56 nmol/L). Moderate affinity was associated with the highest tumor accumulation at 24 and 120 hours after intravenous injection, whereas high affinity was found to produce the lowest tumor accumulation. Highest affinity mAbs were confined to the perivascular space of tumors with an average penetration of 20.4 ± 7.5 μm from tumor blood vessels. Conversely, lowest affinity mAbs exhibited a broader distribution pattern with an average penetration of 84.8 ± 12.8 μm. In vitro internalization assays revealed that antibody internalization and catabolism generally increased with affinity, plateauing once the rate of HER2 internalization exceeded the rate of antibody dissociation. Effects of internalization and catabolism on tumor targeting were further examined using antibodies of moderate (C6.5) or high-affinity (trastuzumab), labeled with residualizing (111In-labeled) or nonresidualizing (125I-labeled) radioisotopes. Significant amounts of antibody of both affinities were degraded by tumors in vivo. Furthermore, moderate- to high-affinity mAbs targeting the same HER2 epitope with monovalent affinity above 23 nmol/L had equal tumor accumulation of residualizing radiolabel over 120 hours. Results indicated equal tumor exposure, suggesting that mAb penetration and retention in tumors reflected affinity-based differences in tumor catabolism. Together, these results suggest that high-density, rapidly internalizing antigens subject high-affinity antibodies to greater internalization and degradation, thereby limiting their penetration of tumors. In contrast, lower-affinity antibodies penetrate tumors more effectively when rates of antibody–antigen dissociation are higher than those of antigen internalization. Together, our findings offer insights into how to optimize the ability of therapeutic antibodies to penetrate tumors. Cancer Res; 71(6); 2250–9. ©2011 AACR.
Data from Antiangiogenic Agent Sunitinib Transiently Increases Tumor Oxygenation and Suppresses Cycling Hypoxia
Authors: Matsumoto Shingo , Batra Sonny , Saito Keita , Yasui Hironobu , Choudhuri Rajani , Gadisetti Chandramouli , Subramanian Sankaran , Devasahayam Nallathamby , Munasinghe Jeeva P. , Mitchell James B. , Krishna Murali C.
Published: March 2024

Abstract
Structural and functional abnormalities in tumor blood vessels impact the delivery of oxygen and nutrients to solid tumors, resulting in chronic and cycling hypoxia. Although chronically hypoxic regions exhibit treatment resistance, more recently it has been shown that cycling hypoxic regions acquire prosurvival pathways. Angiogenesis inhibitors have been shown to transiently normalize the tumor vasculatures and enhance tumor response to treatments. However, the effect of antiangiogenic therapy on cycling tumor hypoxia remains unknown. Using electron paramagnetic resonance imaging and MRI in tumor-bearing mice, we have examined the vascular renormalization process by longitudinally mapping tumor partial pressure of oxygen (pO2) and microvessel density during treatments with a multi-tyrosine kinase inhibitor sunitinib. Transient improvement in tumor oxygenation was visualized by electron paramagnetic resonance imaging 2 to 4 days following antiangiogenic treatments, accompanied by a 45% decrease in microvessel density. Radiation treatment during this time period of improved oxygenation by antiangiogenic therapy resulted in a synergistic delay in tumor growth. In addition, dynamic oxygen imaging obtained every 3 minutes was conducted to distinguish tumor regions with chronic and cycling hypoxia. Sunitinib treatment suppressed the extent of temporal fluctuations in tumor pO2 during the vascular normalization window, resulting in the decrease of cycling tumor hypoxia. Overall, the findings suggest that longitudinal and noninvasive monitoring of tumor pO2 makes it possible to identify a window of vascular renormalization to maximize the effects of combination therapy with antiangiogenic drugs. Cancer Res; 71(20); 6350–9. ©2011 AACR.
Data from A Comprehensive View of Nuclear Receptor Cancer Cistromes
Authors: Tang Qianzi , Chen Yiwen , Meyer Clifford , Geistlinger Tim , Lupien Mathieu , Wang Qian , Liu Tao , Zhang Yong , Brown Myles , Liu Xiaole Shirley
Published: March 2024

Abstract
Nuclear receptors comprise a superfamily of ligand-activated transcription factors that play important roles in both physiology and diseases including cancer. The technologies of chromatin immunoprecipitation followed by array hybridization (ChIP-chip) or massively parallel sequencing (ChIP-seq) has been used to map, at an unprecedented rate, the in vivo genome-wide binding (cistrome) of nuclear receptors in both normal and cancer cells. We developed a curated database of 88 nuclear receptor cistrome data sets and other associated high-throughput data sets including 121 collaborating factor cistromes, 94 epigenomes, and 319 transcriptomes. Through integrative analysis of the curated nuclear receptor ChIP-chip/seq data sets, we discovered novel factor-specific noncanonical motifs that may have important regulatory roles. We also revealed a common feature of nuclear receptor pioneering factors to recognize relatively short and AT-rich motifs. Most nuclear receptors bind predominantly to introns and distal intergenetic regions, and binding sites closer to transcription start sites were found to be neither stronger nor more evolutionarily conserved. Interestingly, while most nuclear receptors appear to be predominantly transcriptional activators, our analysis suggests that the binding of ESR1, RARA, and RARG has both activating and repressive effects. Through meta-analysis of different omic data of the same cancer cell line model from multiple studies, we generated consensus cistrome and expression profiles. We further made probabilistic predictions of the nuclear receptor target genes by integrating cistrome and transcriptome data and validated the predictions using expression data from tumor samples. The final database, with comprehensive cistrome, epigenome, and transcriptome data sets and downstream analysis results, constitutes a valuable resource for the nuclear receptor and cancer community. Cancer Res; 71(22); 6940–7. ©2011 AACR.
Data from TLR3 as a Biomarker for the Therapeutic Efficacy of Double-stranded RNA in Breast Cancer
Authors: Salaun Bruno , Zitvogel Laurence , Asselin-Paturel Carine , Morel Yannis , Chemin Karine , Dubois Clarisse , Massacrier Catherine , Conforti Rosa , Chenard Marie Pierre , Sabourin Jean-Christophe , Goubar Aicha , Lebecque Serge , Pierres Michel , Rimoldi Donata , Romero Pedro , Andre Fabrice
Published: March 2024

Abstract
The discovery of a targeted therapeutic compound along with its companion predictive biomarker is a major goal of clinical development for a personalized anticancer therapy to date. Here we present evidence of the predictive value of TLR3 expression by tumor cells for the efficacy of Poly (A:U) dsRNA in 194 breast cancer patients enrolled in a randomized clinical trial. Adjuvant treatment with double-stranded RNA (dsRNA) was associated with a significant decrease in the risk of metastatic relapse in TLR3 positive but not in TLR3-negative breast cancers. Moreover, we show the functional relevance of TLR3 expression by human tumor cells for the antitumor effects mediated by dsRNA in several preclinical mouse models carried out in immunocompromised animals. These 2 independent lines of evidence relied upon the generation of a novel tool, an anti-TLR3 antibody (40F9.6) validated for routine detection of TLR3 expression on paraffin-embedded tissues. Altogether, these data suggest that dsRNA mediates its therapeutic effect through TLR3 expressed on tumor cells, and could therefore represent an effective targeted treatment in patients with TLR3-positive cancers. Cancer Res; 71(5); 1607–14. ©2011 AACR.
Data from Autocrine CSF-1 and CSF-1 Receptor Coexpression Promotes Renal Cell Carcinoma Growth
Authors: Menke Julia , Kriegsmann Jörg , Schimanski Carl Christoph , Schwartz Melvin M. , Schwarting Andreas , Kelley Vicki R.
Published: March 2024

Abstract
Renal cell carcinoma is increasing in incidence but the molecular mechanisms regulating its growth remain elusive. Coexpression of the monocytic growth factor colony-stimulating factor (CSF)-1 and its receptor CSF-1R on renal tubular epithelial cells (TEC) will promote proliferation and antiapoptosis during regeneration of renal tubules. Here, we show that a CSF-1–dependent autocrine pathway is also responsible for the growth of renal cell carcinoma (RCC). CSF-1 and CSF-1R were coexpressed in RCCs and TECs proximally adjacent to RCCs. CSF-1 engagement of CSF-1R promoted RCC survival and proliferation and reduced apoptosis, in support of the likelihood that CSF-1R effector signals mediate RCC growth. In vivo CSF-1R blockade using a CSF-1R tyrosine kinase inhibitor decreased RCC proliferation and macrophage infiltration in a manner associated with a dramatic reduction in tumor mass. Further mechanistic investigations linked CSF-1 and epidermal growth factor signaling in RCCs. Taken together, our results suggest that budding RCC stimulates the proximal adjacent microenvironment in the kidney to release mediators of CSF-1, CSF-1R, and epidermal growth factor expression in RCCs. Furthermore, our findings imply that targeting CSF-1/CSF-1R signaling may be therapeutically effective in RCCs. Cancer Res; 72(1); 187–200. ©2011 AACR.
Data from Targeting Tumor Hypoxia: Suppression of Breast Tumor Growth and Metastasis by Novel Carbonic Anhydrase IX Inhibitors
Authors: Lou Yuanmei , McDonald Paul C. , Oloumi Arusha , Chia Stephen , Ostlund Christina , Ahmadi Ardalan , Kyle Alastair , auf dem Keller Ulrich , Leung Samuel , Huntsman David , Clarke Blaise , Sutherland Brent W. , Waterhouse Dawn , Bally Marcel , Roskelley Calvin , Overall Christopher M. , Minchinton Andrew , Pacchiano Fabio , Carta Fabrizio , Scozzafava Andrea , Touisni Nadia , Winum Jean-Yves , Supuran Claudiu T. , Dedhar Shoukat
Published: March 2024

Abstract
Carbonic anhydrase IX (CAIX) is a hypoxia and HIF-1–inducible protein that regulates intra- and extracellular pH under hypoxic conditions and promotes tumor cell survival and invasion in hypoxic microenvironments. Interrogation of 3,630 human breast cancers provided definitive evidence of CAIX as an independent poor prognostic biomarker for distant metastases and survival. shRNA-mediated depletion of CAIX expression in 4T1 mouse metastatic breast cancer cells capable of inducing CAIX in hypoxia resulted in regression of orthotopic mammary tumors and inhibition of spontaneous lung metastasis formation. Stable depletion of CAIX in MDA-MB-231 human breast cancer xenografts also resulted in attenuation of primary tumor growth. CAIX depletion in the 4T1 cells led to caspase-independent cell death and reversal of extracellular acidosis under hypoxic conditions in vitro. Treatment of mice harboring CAIX-positive 4T1 mammary tumors with novel CAIX-specific small molecule inhibitors that mimicked the effects of CAIX depletion in vitro resulted in significant inhibition of tumor growth and metastasis formation in both spontaneous and experimental models of metastasis, without inhibitory effects on CAIX-negative tumors. Similar inhibitory effects on primary tumor growth were observed in mice harboring orthotopic tumors comprised of lung metatstatic MDA-MB-231 LM2-4Luc+ cells. Our findings show that CAIX is vital for growth and metastasis of hypoxic breast tumors and is a specific, targetable biomarker for breast cancer metastasis. Cancer Res; 71(9); 3364–76. ©2011 AACR.
Data from Loss of Transcription Factor KLF5 in the Context of p53 Ablation Drives Invasive Progression of Human Squamous Cell Cancer
Authors: Yang Yizeng , Nakagawa Hiroshi , Tetreault Marie-Pier , Billig Janelle , Victor Noel , Goyal Abha , Sepulveda Antonia R. , Katz Jonathan P.
Published: March 2024

Abstract
Squamous cell cancers account for more than half of all human cancers, and esophageal cancer is the sixth leading cause of cancer death worldwide. The majority of esophageal squamous cell carcinomas have identifiable p53 mutations, yet the same p53 mutations are found at comparable frequencies in precancerous dysplasia, indicating that transformation requires additional somatic changes yet to be defined. Here, we show that the zinc finger transcription factor Krüppel-like factor 5 (KLF5) transactivates NOTCH1 in the context of p53 mutation or loss. KLF5 loss limited NOTCH1 activity and was sufficient on its own to transform primary human keratinocytes harboring mutant p53, leading to the formation of invasive tumors. Restoration of NOTCH1 blocked transformation of KLF5-deficient and p53-mutant keratinocytes. Although human dysplastic epithelia accumulated KLF5, KLF5 expression was lost concurrently with NOTCH1 in squamous cell cancers. Taken together, these results define KLF5 loss as a critical event in squamous cell transformation and invasion. Our findings suggest that KLF5 may be a useful diagnostic and therapeutic target in esophageal squamous carcinomas and possibly more generally in other cancers associated with p53 loss of function. Cancer Res; 71(20); 6475–84. ©2011 AACR.
Data from Dishevelled 2 Signaling Promotes Self-Renewal and Tumorigenicity in Human Gliomas
Authors: Pulvirenti Teodoro , Van Der Heijden Maartje , Droms Leif A. , Huse Jason T. , Tabar Viviane , Hall Alan
Published: March 2024

Abstract
Glioblastoma multiforme is the most common glioma variant in adults and is highly malignant. Tumors are thought to harbor a subpopulation of stem-like cancer cells, with the bulk resembling neural progenitor-like cells that are unable to fully differentiate. Although multiple pathways are known to be involved in glioma tumorigenesis, the role of Wnt signaling has been poorly described. Here, we show that Dishevelled 2 (Dvl2), a key component of the Wnt signaling pathway, is overexpressed in human gliomas. RNA interference–mediated depletion of Dvl2 blocked proliferation and promoted the differentiation of cultured human glioma cell lines and primary, patient-derived glioma cells. In addition, Dvl2 depletion inhibited tumor formation after intracranial injection of glioblastoma cells in immunodeficient mice. Inhibition of canonical Wnt/β-catenin signaling also blocked proliferation, but unlike Dvl2 depletion, did not induce differentiation. Finally, Wnt5a, a noncanonical Wnt ligand, was also required for glioma cell proliferation. The data therefore suggest that both canonical and noncanonical Wnt signaling pathways downstream of Dvl2 cooperate to maintain the proliferative capacity of human glioblastomas. Cancer Res; 71(23); 7280–90. ©2011 AACR.
Data from Evolution of Tumor Invasiveness: The Adaptive Tumor Microenvironment Landscape Model
Authors: Lee Hyung-Ok , Silva Ariosto S. , Concilio Susanna , Li Yue-Sheng , Slifker Michael , Gatenby Robert A. , Cheng Jonathan D.
Published: March 2024

Abstract
Interactions between cancer cells and their microenvironment are crucial for promoting tumor growth and invasiveness. In the tumor adaptive landscape model, hypoxic and acidic microenvironmental conditions reduce the fitness of cancer cells and significantly restrict their proliferation. This selects for enhanced motility as cancer cells may evolve an invasive phenotype if the consequent cell movement is rewarded by proliferation. Here, we used an integrative approach combining a mathematical tumor adaptive landscape model with experimental studies to examine the evolutionary dynamics that promote an invasive cancer phenotype. Computer simulation results hypothesized an explicit coupling of motility and proliferation in cancer cells. The mathematical modeling results were also experimentally examined by selecting Panc-1 cells with enhanced motility on a fibroblast-derived 3-dimensional matrix for cells that move away from the unfavorable metabolic constraints. After multiple rounds of selection, the cells that adapted through increased motility were characterized for their phenotypic properties compared with stationary cells. Microarray and gene depletion studies showed the role of Rho-GDI2 in regulating both cell movement and proliferation. Together, this work illustrates the partnership between evolutionary mathematical modeling and experimental validation as a potentially useful approach to study the complex dynamics of the tumor microenvironment. Cancer Res; 71(20); 6327–37. ©2011 AACR.
Data from Long Noncoding RNA HOTAIR Regulates Polycomb-Dependent Chromatin Modification and Is Associated with Poor Prognosis in Colorectal Cancers
Authors: Kogo Ryunosuke , Shimamura Teppei , Mimori Koshi , Kawahara Kohichi , Imoto Seiya , Sudo Tomoya , Tanaka Fumiaki , Shibata Kohei , Suzuki Akira , Komune Shizuo , Miyano Satoru , Mori Masaki
Published: March 2024

Abstract
The functional impact of recently discovered long noncoding RNAs (ncRNAs) in human cancer remains to be clarified. One long ncRNA which has attracted attention is the Hox transcript antisense intergenic RNA termed HOTAIR, a long ncRNA expressed from the developmental HOXC locus located on chromosome 12q13.13. In cooperation with Polycomb complex PRC2, the HOTAIR long ncRNA is reported to reprogram chromatin organization and promote breast cancer metastasis. In this study, we examined the status and function of HOTAIR in patients with stage IV colorectal cancer (CRC) who have liver metastases and a poor prognosis. HOTAIR expression levels were higher in cancerous tissues than in corresponding noncancerous tissues and high HOTAIR expression correlated tightly with the presence of liver metastasis. Moreover, patients with high HOTAIR expression had a relatively poorer prognosis. In a subset of 32 CRC specimens, gene set enrichment analysis using cDNA array data revealed a close correlation between expression of HOTAIR and members of the PRC2 complex (SUZ12, EZH2, and H3K27me3). Our findings suggest that HOTAIR expression is associated with a genome-wide reprogramming of PRC2 function not only in breast cancer but also in CRC, where upregulation of this long ncRNA may be a critical element in metastatic progression. Cancer Res; 71(20); 6320–6. ©2011 AACR.
Data from Use of Macrophages to Target Therapeutic Adenovirus to Human Prostate Tumors
Authors: Muthana Munitta , Giannoudis Athina , Scott Simon D. , Fang Hsin-Yu , Coffelt Seth B. , Morrow Fiona J. , Murdoch Craig , Burton Julian , Cross Neil , Burke Bernard , Mistry Roshna , Hamdy Freddie , Brown Nicola J. , Georgopoulos Lindsay , Hoskin Peter , Essand Magnus , Lewis Claire E. , Maitland Norman J.
Published: March 2024

Abstract
New therapies are required to target hypoxic areas of tumors as these sites are highly resistant to conventional cancer therapies. Monocytes continuously extravasate from the bloodstream into tumors where they differentiate into macrophages and accumulate in hypoxic areas, thereby opening up the possibility of using these cells as vehicles to deliver gene therapy to these otherwise inaccessible sites. We describe a new cell-based method that selectively targets an oncolytic adenovirus to hypoxic areas of prostate tumors. In this approach, macrophages were cotransduced with a hypoxia-regulated E1A/B construct and an E1A-dependent oncolytic adenovirus, whose proliferation is restricted to prostate tumor cells using prostate-specific promoter elements from the TARP, PSA, and PMSA genes. When such cotransduced cells reach an area of extreme hypoxia, the E1A/B proteins are expressed, thereby activating replication of the adenovirus. The virus is subsequently released by the host macrophage and infects neighboring tumor cells. Following systemic injection into mice bearing subcutaneous or orthotopic prostate tumors, cotransduced macrophages migrated into hypoxic tumor areas, upregulated E1A protein, and released multiple copies of adenovirus. The virus then infected neighboring cells but only proliferated and was cytotoxic in prostate tumor cells, resulting in the marked inhibition of tumor growth and reduction of pulmonary metastases. This novel delivery system employs 3 levels of tumor specificity: the natural “homing” of macrophages to hypoxic tumor areas, hypoxia-induced proliferation of the therapeutic adenovirus in host macrophages, and targeted replication of oncolytic virus in prostate tumor cells. Cancer Res; 71(5); 1805–15. ©2011 AACR.
Data from Downregulation of RBMS3 Is Associated with Poor Prognosis in Esophageal Squamous Cell Carcinoma
Authors: Li Yan , Chen Leilei , Nie Chang-jun , Zeng Ting-ting , Liu Haibo , Mao Xueying , Qin Yanru , Zhu Ying-Hui , Fu Li , Guan Xin-Yuan
Published: March 2024

Abstract
Deletions on chromosome 3p occur often in many solid tumors, including esophageal squamous cell carcinoma (ESCC), suggesting the existence at this location of one or more tumor suppressor genes (TSG). In this study, we characterized RBMS3 gene encoding an RNA-binding protein as a candidate TSG located at 3p24. Downregulation of RBMS3 mRNA and protein levels was documented in approximately 50% of the primary ESCCs examined. Clinical association studies determined that RBMS3 downregulation was associated with poor clinical outcomes. RBMS3 expression effectively suppressed the tumorigenicity of ESCC cells in vitro and in vivo, including by inhibition of cell growth rate, foci formation, soft agar colony formation, and tumor formation in nude mice. Molecular analyses revealed that RBMS3 downregulated c-Myc and CDK4, leading to subsequent inhibition of Rb phosphorylation. Together, our findings suggest a tumor suppression function for the human RBMS3 gene in ESCC, acting through c-Myc downregulation, with genetic loss of this gene in ESCC contributing to poor outcomes in this deadly disease. Cancer Res; 71(19); 6106–15. ©2011 AACR.
Data from Androgen Receptor and Nutrient Signaling Pathways Coordinate the Demand for Increased Amino Acid Transport during Prostate Cancer Progression
Authors: Wang Qian , Bailey Charles G. , Ng Cynthia , Tiffen Jessamy , Thoeng Annora , Minhas Vineet , Lehman Melanie L. , Hendy Stephen C. , Buchanan Grant , Nelson Colleen C. , Rasko John E.J. , Holst Jeff
Published: March 2024

Abstract
l-Type amino acid transporters such as LAT1 and LAT3 mediate the uptake of essential amino acids. Here, we report that prostate cancer cells coordinate the expression of LAT1 and LAT3 to maintain sufficient levels of leucine needed for mTORC1 signaling and cell growth. Inhibiting LAT function was sufficient to decrease cell growth and mTORC1 signaling in prostate cancer cells. These cells maintained levels of amino acid influx through androgen receptor–mediated regulation of LAT3 expression and ATF4 regulation of LAT1 expression after amino acid deprivation. These responses remained intact in primary prostate cancer, as indicated by high levels of LAT3 in primary disease, and by increased levels of LAT1 after hormone ablation and in metastatic lesions. Taken together, our results show how prostate cancer cells respond to demands for increased essential amino acids by coordinately activating amino acid transporter pathways vital for tumor outgrowth. Cancer Res; 71(24); 7525–36. ©2011 AACR.
Data from DCAMKL-1 Regulates Epithelial–Mesenchymal Transition in Human Pancreatic Cells through a miR-200a–Dependent Mechanism
Authors: Sureban Sripathi M. , May Randal , Lightfoot Stan A. , Hoskins Aimee B. , Lerner Megan , Brackett Daniel J. , Postier Russell G. , Ramanujam Rama , Mohammed Altaf , Rao Chinthalapally V. , Wyche James H. , Anant Shrikant , Houchen Courtney W.
Published: March 2024

Abstract
Pancreatic cancer is an exceptionally aggressive disease in great need of more effective therapeutic options. Epithelial–mesenchymal transition (EMT) plays a key role in cancer invasion and metastasis, and there is a gain of stem cell properties during EMT. Here we report increased expression of the putative pancreatic stem cell marker DCAMKL-1 in an established KRAS transgenic mouse model of pancreatic cancer and in human pancreatic adenocarcinoma. Colocalization of DCAMKL-1 with vimentin, a marker of mesenchymal lineage, along with 14-3-3 σ was observed within premalignant PanIN lesions that arise in the mouse model. siRNA-mediated knockdown of DCAMKL-1 in human pancreatic cancer cells induced microRNA miR-200a, an EMT inhibitor, along with downregulation of EMT-associated transcription factors ZEB1, ZEB2, Snail, Slug, and Twist. Furthermore, DCAMKL-1 knockdown resulted in downregulation of c-Myc and KRAS through a let-7a microRNA-dependent mechanism, and downregulation of Notch-1 through a miR-144 microRNA-dependent mechanism. These findings illustrate direct regulatory links between DCAMKL-1, microRNAs, and EMT in pancreatic cancer. Moreover, they demonstrate a functional role for DCAMKL-1 in pancreatic cancer. Together, our results rationalize DCAMKL-1 as a therapeutic target for eradicating pancreatic cancers. Cancer Res; 71(6); 2328–38. ©2011 AACR.
Data from Forkhead Transcription Factor Foxq1 Promotes Epithelial–Mesenchymal Transition and Breast Cancer Metastasis
Authors: Zhang Haijun , Meng Fanyan , Liu Gang , Zhang Bin , Zhu Jun , Wu Feng , Ethier Stephen P. , Miller Fred , Wu Guojun
Published: March 2024

Abstract
Epithelial–mesenchymal transition (EMT) promotes cancer invasion and metastasis, but the integrative mechanisms that coordinate these processes are incompletely understood. In this study, we used a cross-species expression profiling strategy in metastatic cell lines of human and mouse origin to identify 22 up-regulated and 12 down-regulated genes that are part of an essential genetic program in metastasis. In particular, we identified a novel function in metastasis that was not previously known for the transcription factor Forkhead Box Q1 (Foxq1). Ectopic expression of Foxq1 increased cell migration and invasion in vitro, enhanced the lung metastatic capabilities of mammary epithelial cells in vivo, and triggered a marked EMT. In contrast, Foxq1 knockdown elicited converse effects on these phenotypes in vitro and in vivo. Neither ectopic expression nor knockdown of Foxq1 significantly affected cell proliferation or colony formation in vitro. Notably, Foxq1 repressed expression of the core EMT regulator E-cadherin by binding to the E-box in its promoter region. Further mechanistic investigation revealed that Foxq1 expression is regulated by TGF-β1, and that Foxq1 knockdown blocked TGF-β1-induced EMT at both morphological and molecular levels. Our findings highlight the feasibility of cross-species expression profiling as a strategy to identify metastasis-related genes, and they reveal that EMT induction is a likely mechanism underlying a novel metastasis-promoting function of Foxq1 defined here in breast cancer. Cancer Res; 71(4); 1292–301. ©2011 AACR.
Data from miR-218 Suppresses Nasopharyngeal Cancer Progression through Downregulation of Survivin and the SLIT2-ROBO1 Pathway
Authors: Alajez Nehad M. , Lenarduzzi Michelle , Ito Emma , Hui Angela B.Y. , Shi Wei , Bruce Jeff , Yue Shijun , Huang Shao H. , Xu Wei , Waldron John , O'Sullivan Brian , Liu Fei-Fei
Published: March 2024

Abstract
Nasopharayngeal carcinoma (NPC) is an Epstein–Barr virus–associated malignancy most common in East Asia and Africa. Here we report frequent downregulation of the microRNA miR-218 in primary NPC tissues and cell lines where it plays a critical role in NPC progression. Suppression of miR-218 was associated with epigenetic silencing of SLIT2 and SLIT3, ligands of ROBO receptors that have been previously implicated in tumor angiogenesis. Exogenous expression of miR-218 caused significant toxicity in NPC cells in vitro and delayed tumor growth in vivo. We used an integrated trimodality approach to identify targets of miR-218 in NPC, cervical, and breast cell lines. Direct interaction between miR-218 and the 3′-untranslated regions (UTR) of mRNAs encoding ROBO1, survivin (BIRC5), and connexin43 (GJA1) was validated in a luciferase-based transcription reporter assay. Mechanistic investigations revealed a negative feedback loop wherein miR-218 regulates NPC cell migration via the SLIT-ROBO pathway. Pleotropic effects of miR-218 on NPC survival and migration were rescued by enforced expression of miR-218–resistant, engineered isoforms of survivin and ROBO1, respectively. In clinical specimens of NPC (n = 71), ROBO1 overexpression was significantly associated with worse overall (P = 0.04, HR = 2.4) and nodal relapse-free survival (P = 0.008, HR = 6.0). Our findings define an integrative tumor suppressor function for miR-218 in NPC and further suggest that restoring miR-218 expression in NPC might be useful for its clinical management. Cancer Res; 71(6); 2381–91. ©2011 AACR.
Data from Increased Skin Papilloma Formation in Mice Lacking Glutathione Transferase GSTP
Authors: Henderson Colin J. , Ritchie Kenneth J. , McLaren Aileen , Chakravarty Probir , Wolf C. Roland
Published: March 2024

Abstract
The glutathione S-transferase GSTP is overexpressed in many human cancers and chemotherapy-resistant cancer cells, where there is evidence that GSTP may have additional functions beyond its known catalytic role. On the basis of evidence that Gstp-deficient mice have a comparatively higher susceptibility to skin carcinogenesis, we investigated whether this phenotype reflected an alteration in carcinogen detoxification or not. For this study, Gstp−/− mice were interbred with Tg.AC mice that harbor initiating H-ras mutations in the skin. Gstp−/−/Tg.AC mice exposed to the proinflammatory phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) exhibited higher tumor incidence and multiplicity with a significant thickening of skin after treatment, illustrating hyperproliferative growth. Unexpectedly, we observed no difference in cellular proliferation or apoptosis or in markers of oxidative stress, although higher levels of the inflammatory marker nitrotyrosine were found in Gstp−/−/Tg.AC mice. Instead, gene set enrichment analysis of microarray expression data obtained from skin revealed a more proapoptotic and proinflammatory environment shortly after TPA treatment. Within 4 weeks of TPA treatment, Gstp−/−/Tg.AC mice displayed altered lipid/sterol metabolism and Wnt signaling along with aberrant processes of cytoskeletal control and epidermal morphogenesis at both early and late times. In extending the evidence that GSTP has a vital role in normal homeostatic control and cancer prevention, they also strongly encourage the emerging concept that GSTP is a major determinant of the proinflammatory character of the tumor microenvironment. This study shows that the GSTP plays a major role in carcinogenesis distinct from its role in detoxification and provides evidence that the enzyme is a key determinant of the proinflammatory tumor environment. Cancer Res; 71(22); 7048–60. ©2011 AACR.
Data from 14-3-3σ Exerts Tumor-Suppressor Activity Mediated by Regulation of COP1 Stability
Authors: Su Chun-Hui , Zhao Ruiying , Zhang Fanmao , Qu Changju , Chen Bo , Feng Yin-Hsun , Phan Liem , Chen Jian , Wang Hua , Wang Huamin , Yeung Sai-Ching J. , Lee Mong-Hong
Published: March 2024

Abstract
Constitutive photomorphogenic 1 (COP1) is a p53-targeting E3 ubiquitin ligase that is downregulated by DNA damage through mechanisms that remain obscure. Here, we report that COP1 is not downregulated following DNA damage in 14-3-3σ null cells, implicating 14-3-3σ as a critical regulator in the response of COP1 to DNA damage. We also identified that 14-3-3σ, a p53 target gene product, interacted with COP1 and controlled COP1 protein stability after DNA damage. Mechanistic studies revealed that 14-3-3σ enhanced COP1 self-ubiquitination, thereby preventing COP1-mediated p53 ubiquitination, degradation, and transcriptional repression. In addition, we found that COP1 expression promoted cell proliferation, cell transformation, and tumor progression, manifesting its role in cancer promotion, whereas 14-3-3σ negatively regulated COP1 function and prevented tumor growth in a mouse xenograft model of human cancer. Immunohistochemical analysis of clinical breast and pancreatic cancer specimens demonstrated that COP1 protein levels were inversely correlated with 14-3-3σ protein levels. Together, our findings define a mechanism for posttranslational regulation of COP1 after DNA damage that can explain the correlation between COP1 overexpression and 14-3-3σ downregulation during tumorigenesis. Cancer Res; 71(3); 884–94. ©2010 AACR.
Data from Hypoxia Predicts Aggressive Growth and Spontaneous Metastasis Formation from Orthotopically Grown Primary Xenografts of Human Pancreatic Cancer
Authors: Chang Qing , Jurisica Igor , Do Trevor , Hedley David W.
Published: March 2024

Abstract
Hypoxia in solid tumors is associated with treatment resistance and increased metastatic potential. Although hypoxia has been reported in pancreatic cancer patients, there is little direct evidence that this contributes to their overall poor prognosis. To address this, we examined the associations between hypoxia and biological aggression in a series of patient-derived xenografts grown orthotopically. Early passage xenografts were established from 16 patients undergoing surgery for pancreatic cancer and maintained in the pancreas of immune-deprived mice. Hypoxic cells were labeled using the 2-nitroimidazole probe EF5 and stained for immunofluorescence microscopy of tissue sections or as cell suspensions for flow cytometry. Bromodeoxyuridine (BrdUrd) uptake, microvessel density, cleaved caspase-3, and the differentiation markers E-cadherin, cytokeratin 19, and vimentin were analyzed in relation to hypoxia. Orthotopic implants closely resembled the histology of the original surgical samples. The 16 primary xenografts showed a wide range in their growth rates and metastatic potential, reminiscent of the spectrum of behavior seen in the clinic. EF5 labeling, tumor growth rates, and metastatic patterns were highly consistent within replicates, indicating a significant transmissible (genetic or epigenetic) component. Hypoxia was highly correlated with rapid tumor growth, increased BrdUrd uptake, and with spontaneous metastasis formation. mRNA expression analysis showed increased expression of genes involved in cell survival and proliferation in the hypoxic models. The results suggest that hypoxia is a major adverse prognostic factor in pancreatic cancer patients and support the introduction of techniques to measure hypoxia directly in patients and the development of treatment protocols to target hypoxia. Cancer Res; 71(8); 3110–20. ©2011 AACR.