bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Monoclonal Antibody Targeting of the Cell Surface Molecule TM4SF5 Inhibits the Growth of Hepatocellular Carcinoma
Authors: Kwon Sanghoon , Choi Kyung-Chan , Kim Young-Eun , Ha Yang-Wha , Kim Dongbum , Park Byoung Kwon , Wu Guang , Kim Doo-Sik , Lee Younghee , Kwon Hyung-Joo
Published: March 2024

Abstract
The cell surface transmembrane receptor TM4SF5 has been implicated in hepatocellular carcinoma (HCC), but its candidacy as a therapeutic target has not been evaluated. Building on findings that immunization with a peptide vaccine targeting human TM4SF5 can exert prophylactic and therapeutic effects in a murine model of HCC, we developed a monoclonal antibody to characterize expression of TM4SF5 in HCC and to target its function there as an anticancer strategy. We found that the antibody modulated cell signaling in HCC cells in vitro, reducing cell motility, modulating E-cadherin expression, altering p27kip1 localization, and increasing RhoA activity. Using a mouse xenograft model of human HCC, we documented the in vivo efficacy of the antibody, which suppressed tumor growth in either tumor prevention or treatment designs. Our work offers a preclinical proof of concept for TM4SF5 as a promising target for antibody therapeutics to treat HCC. Cancer Res; 74(14); 3844–56. ©2014 AACR.
Data from 3′-UTR Poly(T/U) Tract Deletions and Altered Expression of EWSR1 Are a Hallmark of Mismatch Repair–Deficient Cancers
Authors: Kishore Shivendra , Piscuoglio Salvatore , Kovac Michal B. , Gylling Annette , Wenzel Friedel , Trapani Francesca , Altermatt Hans Joerg , Mele Valentina , Marra Giancarlo , Peltomäki Päivi , Terracciano Luigi , Zavolan Mihaela , Heinimann Karl
Published: March 2024

Abstract
The genome-wide accumulation of DNA replication errors known as microsatellite instability (MSI) is the hallmark lesion of DNA mismatch repair (MMR)–deficient cancers. Although testing for MSI is widely used to guide clinical management, the contribution of MSI at distinct genic loci to the phenotype remains largely unexplored. Here, we report that a mononucleotide (T/U)16 tract located in the 3′ untranslated region (3′-UTR) of the Ewing sarcoma breakpoint region 1 (EWSR1) gene is a novel MSI target locus that shows perfect sensitivity and specificity in detecting mismatch repair–deficient cancers in two independent populations. We further found a striking relocalization of the EWSR1 protein from nucleus to cytoplasm in MMR-deficient cancers and that the nonprotein-coding MSI target locus itself has a modulatory effect on EWSR1 gene expression through alternative 3′ end processing of the EWSR1 gene. Our results point to a MSI target gene–specific effect in MMR-deficient cancers. Cancer Res; 74(1); 224–34. ©2013 AACR.
Data from Human Rhomboid Family-1 Suppresses Oxygen-Independent Degradation of Hypoxia-Inducible Factor-1α in Breast Cancer
Authors: Zhou Zhuan , Liu Fangfang , Zhang Zhi-Song , Shu Feifei , Zheng Yangyang , Fu Li , Li Lu-Yuan
Published: March 2024

Abstract
Intermittent oxygen deficiency in cancers promotes prolonged inflammation, continuous angiogenesis, and increased drug resistance. Hypoxia-inducible factor-1 (HIF1) has a pivotal role in the regulation of cellular responses to oxygen deficiency. The α-subunit of HIF1 (HIF1α) is degraded in normoxia but stabilized in hypoxia. However, the molecular mechanism that controls oxygen-independent degradation of HIF1α has remained elusive. Human rhomboid family-1 (RHBDF1) is a member of a large family of nonprotease rhomboids whose function is basically unknown. We report here that RHBDF1 expression in breast cancer is highly elevated and is strongly correlated with escalated disease progression, metastasis, poor prognosis, and poor response to chemotherapy. We show that RHBDF1 interaction with the receptor of activated protein-C kinase-1 (RACK1) in breast cancer cells prevents RACK1-assisted, oxygen-independent HIF1α degradation. In addition, we show that the HIF1α-stabilizing activity of RHBDF1 diminishes when the phosphorylation of a tyrosine residue on the RHBDF1 molecule is inhibited. These findings are consistent with the view that RHBDF1 is a critical component of a molecular switch that regulates HIF1α stability in cancer cells in hypoxia and that RHBDF1 is of potential value as a new target for cancer treatment. Cancer Res; 74(10); 2719–30. ©2014 AACR.
Data from G Protein–Coupled Receptor Kinase GRK5 Phosphorylates Moesin and Regulates Metastasis in Prostate Cancer
Authors: Chakraborty Prabir Kumar , Zhang Yushan , Coomes Alexandra S. , Kim Wan-Ju , Stupay Rachel , Lynch Lauren D. , Atkinson Tamieka , Kim Jae I. , Nie Zhongzhen , Daaka Yehia
Published: March 2024

Abstract
G protein–coupled receptor kinases (GRK) regulate diverse cellular functions ranging from metabolism to growth and locomotion. Here, we report an important contributory role for GRK5 in human prostate cancer. Inhibition of GRK5 kinase activity attenuated the migration and invasion of prostate cancer cells and, concordantly, increased cell attachment and focal adhesion formation. Mass spectrometric analysis of the phosphoproteome revealed the cytoskeletal-membrane attachment protein moesin as a putative GRK5 substrate. GRK5 regulated the subcellular distribution of moesin and colocalized with moesin at the cell periphery. We identified amino acid T66 of moesin as a principal GRK5 phosphorylation site and showed that enforcing the expression of a T66-mutated moesin reduced cell spreading. In a xenograft model of human prostate cancer, GRK5 silencing reduced tumor growth, invasion, and metastasis. Taken together, our results established GRK5 as a key contributor to the growth and metastasis of prostate cancer. Cancer Res; 74(13); 3489–500. ©2014 AACR.
Data from Skin Tumorigenesis Stimulated by Raf Inhibitors Relies Upon Raf Functions That Are Dependent and Independent of ERK
Authors: Doma Eszter , Rupp Christian , Varga Andrea , Kern Florian , Riegler Bettina , Baccarini Manuela
Published: March 2024

Abstract
RAF inhibitors achieve unprecedented but mainly transient clinical responses in patients with melanoma whose tumors harbor an activating BRAF mutation. One notable side-effect of RAF inhibitors is the stimulation of cutaneous skin tumors, arising in about 30% of patients receiving these drugs, which are thought to develop as a result of inhibitor-induced activation of wild-type Raf in occult precursor skin lesions. This effect raises the possibility that less manageable tumors might also arise in other epithelial tissues. Here we provide preclinical evidence supporting this disquieting hypothesis by showing that the RAF inhibitors PLX-4032 (vemurafenib) and GDC-0879 precipitate the development of cell-autonomous, Ras-driven tumors in skin and gastric epithelia. The magnitude of the effects correlated with the inhibitors' relative abilities to induce ERK activation. Epidermis-restricted ablation of either B-Raf or C-Raf prevented PLX-4032–induced ERK activation and tumorigenesis. In contrast, GDC-0879 induced ERK activation and tumorigenesis in B-Raf–deficient epidermis, whereas C-Raf ablation blocked GDC-0879–induced tumorigenesis (despite strong ERK activation) by preventing Rokα–mediated keratinocyte dedifferentiation. Thus, inhibitor-induced ERK activation did not require a specific Raf kinase. ERK activation was necessary, but not sufficient for Ras + Raf inhibitor-induced tumorigenesis, whereas C-Raf downregulation of Rokα was essential even in the face of sustained ERK signaling to prevent differentiation and promote tumorigenesis. Taken together, our findings suggest that combination therapies targeting ERK-dependent and -independent functions of Raf may be more efficient but also safer for cancer treatment. Cancer Res; 73(23); 6926–37. ©2013 AACR.
Data from Targeting uPAR with Antagonistic Recombinant Human Antibodies in Aggressive Breast Cancer
Authors: LeBeau Aaron M. , Duriseti Sai , Murphy Stephanie T. , Pepin Francois , Hann Byron , Gray Joe W. , VanBrocklin Henry F. , Craik Charles S.
Published: March 2024

Abstract
Components of the plasminogen activation system, which are overexpressed in aggressive breast cancer subtypes, offer appealing targets for development of new diagnostics and therapeutics. By comparing gene expression data in patient populations and cultured cell lines, we identified elevated levels of the urokinase plasminogen activation receptor (uPAR, PLAUR) in highly aggressive breast cancer subtypes and cell lines. Recombinant human anti-uPAR antagonistic antibodies exhibited potent binding in vitro to the surface of cancer cells expressing uPAR. In vivo these antibodies detected uPAR expression in triple negative breast cancer (TNBC) tumor xenografts using near infrared imaging and 111In single-photon emission computed tomography. Antibody-based uPAR imaging probes accurately detected small disseminated lesions in a tumor metastasis model, complementing the current clinical imaging standard 18F-fluorodeoxyglucose at detecting non-glucose-avid metastatic lesions. A monotherapy study using the antagonistic antibodies resulted in a significant decrease in tumor growth in a TNBC xenograft model. In addition, a radioimmunotherapy study, using the anti-uPAR antibodies conjugated to the therapeutic radioisotope 177Lu, found that they were effective at reducing tumor burden in vivo. Taken together, our results offer a preclinical proof of concept for uPAR targeting as a strategy for breast cancer diagnosis and therapy using this novel human antibody technology. Cancer Res; 73(7); 2070–81. ©2013 AACR.
Data from Optimal Effector Functions in Human Natural Killer Cells Rely upon Autocrine Bone Morphogenetic Protein Signaling
Authors: Robson Neil C. , Hidalgo Laura , McAlpine Tristan , Wei Heng , Martínez Víctor G. , Entrena Ana , Melen Gustavo J. , MacDonald Andrew S. , Phythian-Adams Alexander , Sacedón Rosa , Maraskovsky Eugene , Cebon Jonathan , Ramírez Manuel , Vicente Angeles , Varas Alberto
Published: March 2024

Abstract
Natural killer (NK) cells are critical for innate tumor immunity due to their specialized ability to recognize and kill neoplastically transformed cells. However, NK cells require a specific set of cytokine-mediated signals to achieve optimal effector function. Th1-associated cytokines promote effector functions that are inhibited by the prototypic Th2 cytokine IL4 and the TGFβ superfamily members TGFβ1 and activin-A. Interestingly, the largest subgroup of the TGFβ superfamily are the bone morphogenetic proteins (BMP), but the effects of BMP signaling on NK cell effector functions have not been evaluated. Here, we demonstrate that blood-circulating NK cells express type I and II BMP receptors, BMP-2 and BMP-6 ligands, and phosphorylated isoforms of Smad-1/-5/-8, which mediate BMP family member signaling. In opposition to the inhibitory effects of TGFβ1 or activin-A, autocrine BMP signaling was supportive to NK cell function. Mechanistic investigations in cytokine and TLR-L–activated NK cells revealed that BMP signaling optimized IFNγ and global cytokine and chemokine production, phenotypic activation and proliferation, and autologous dendritic cell activation and target cytotoxicity. Collectively, our findings identify a novel auto-activatory pathway that is essential for optimal NK cell effector function, one that might be therapeutically manipulated to help eradicate tumors. Cancer Res; 74(18); 5019–31. ©2014 AACR.
Data from Neutralizing Murine TGFβR2 Promotes a Differentiated Tumor Cell Phenotype and Inhibits Pancreatic Cancer Metastasis
Authors: Ostapoff Katherine T. , Cenik Bercin Kutluk , Wang Miao , Ye Risheng , Xu Xiaohong , Nugent Desiree , Hagopian Moriah M. , Topalovski Mary , Rivera Lee B. , Carroll Kyla D. , Brekken Rolf A.
Published: March 2024

Abstract
Elevated levels of TGFβ are a negative prognostic indicator for patients diagnosed with pancreatic cancer; as a result, the TGFβ pathway is an attractive target for therapy. However, clinical application of pharmacologic inhibition of TGFβ remains challenging because TGFβ has tumor suppressor functions in many epithelial malignancies, including pancreatic cancer. In fact, direct neutralization of TGFβ promotes tumor progression of genetic murine models of pancreatic cancer. Here, we report that neutralizing the activity of murine TGFβ receptor 2 using a monoclonal antibody (2G8) has potent antimetastatic activity in orthotopic human tumor xenografts, syngeneic tumors, and a genetic model of pancreatic cancer. 2G8 reduced activated fibroblasts, collagen deposition, microvessel density, and vascular function. These stromal-specific changes resulted in tumor cell epithelial differentiation and a potent reduction in metastases. We conclude that TGFβ signaling within stromal cells participates directly in tumor cell phenotype and pancreatic cancer progression. Thus, strategies that inhibit TGFβ-dependent effector functions of stromal cells could be efficacious for the therapy of pancreatic tumors. Cancer Res; 74(18); 4996–5007. ©2014 AACR.
Data from LEO1 Is Regulated by PRL-3 and Mediates Its Oncogenic Properties in Acute Myelogenous Leukemia
Authors: Chong Phyllis S.Y. , Zhou Jianbiao , Cheong Lip-Lee , Liu Shaw-Cheng , Qian Jingru , Guo Tiannan , Sze Siu Kwan , Zeng Qi , Chng Wee Joo
Published: March 2024

Abstract
PRL-3, an oncogenic dual-specificity phosphatase, is overexpressed in 50% of acute myelogenous leukemia (AML) and associated with poor survival. We found that stable expression of PRL-3 confers cytokine independence and growth advantage of AML cells. However, how PRL-3 mediates these functions in AML is not known. To comprehensively screen for PRL3-regulated proteins in AML, we performed SILAC-based quantitative proteomics analysis and discovered 398 significantly perturbed proteins after PRL-3 overexpression. We show that Leo1, a component of RNA polymerase II–associated factor (PAF) complex, is a novel and important mediator of PRL-3 oncogenic activities in AML. We described a novel mechanism where elevated PRL-3 protein increases JMJD2C histone demethylase occupancy on Leo1 promoter, thereby reducing the H3K9me3 repressive signals and promoting Leo1 gene expression. Furthermore, PRL-3 and Leo1 levels were positively associated in AML patient samples (N = 24; P < 0.01). On the other hand, inhibition of Leo1 reverses PRL-3 oncogenic phenotypes in AML. Loss of Leo1 leads to destabilization of the PAF complex and downregulation of SOX2 and SOX4, potent oncogenes in myeloid transformation. In conclusion, we identify an important and novel mechanism by which PRL-3 mediates its oncogenic function in AML. Cancer Res; 74(11); 3043–53. ©2014 AACR.
Data from Mesenchymal Stem Cells Use IDO to Regulate Immunity in Tumor Microenvironment
Authors: Ling Weifang , Zhang Jimin , Yuan Zengrong , Ren Guangwen , Zhang Liying , Chen Xiaodong , Rabson Arnold B. , Roberts Arthur I. , Wang Ying , Shi Yufang
Published: March 2024

Abstract
Mesenchymal stem cells (MSC) are present in most, if not all, tissues and are believed to contribute to tissue regeneration and the tissue immune microenvironment. Murine MSCs exert immunosuppressive effects through production of inducible nitric oxide synthase (iNOS), whereas human MSCs use indoleamine 2,3-dioxygenase (IDO). Thus, studies of MSC-mediated immunomodulation in mice may not be informative in the setting of human disease, although this critical difference has been mainly ignored. To address this issue, we established a novel humanized system to model human MSCs, using murine iNOS−/− MSCs that constitutively or inducibly express an ectopic human IDO gene. In this system, inducible IDO expression is driven by a mouse iNOS promoter that can be activated by inflammatory cytokine stimulation in a similar fashion as the human IDO promoter. These IDO-expressing humanized MSCs (MSC-IDO) were capable of suppressing T-lymphocyte proliferation in vitro. In melanoma and lymphoma tumor models, MSC-IDO promoted tumor growth in vivo, an effect that was reversed by the IDO inhibitor 1-methyl-tryptophan. We found that MSC-IDO dramatically reduced both tumor-infiltrating CD8+ T cells and B cells. Our findings offer an important new line of evidence that interventional targeting of IDO activity could be used to restore tumor immunity in humans, by relieving IDO-mediated immune suppression of MSCs in the tumor microenvironment as well as in tumor cells themselves. Cancer Res; 74(5); 1576–87. ©2014 AACR.
Data from PP2A-B55β Antagonizes Cyclin E1 Proteolysis and Promotes Its Dysregulation in Cancer
Authors: Tan YingMeei , Sun Dahui , Jiang Weijian , Klotz-Noack Kathleen , Vashisht Ajay A. , Wohlschlegel James , Widschwendter Martin , Spruck Charles
Published: March 2024

Abstract
Cyclin E1 regulates the initiation of S-phase in cellular division. However, in many cancers, cyclin E1 is aberrantly overexpressed and this molecular phenotype correlates with increased tumor aggressiveness and poor patient survival. The molecular cause(s) of cyclin E1 abnormalities in cancers is poorly understood. Here, we show that cyclin E1 overexpression in cancer is promoted by dysregulation of the protein phosphatase PP2A-B55β. PP2A-B55β targets the N- and C-terminal phosphodegrons of cyclin E1 for dephosphorylation, thus protecting it from degradation mediated by the SCFFbxw7 ubiquitin ligase. Augmented B55β expression stabilizes cyclin E1 and promotes its overexpression in cancer-derived cell lines and breast tumors. Conversely, B55β ablation enforces the degradation of cyclin E1 and inhibits cancer cell proliferation in vitro and tumor formation in vivo. Therefore, PP2A-B55β promotes cyclin E1 overexpression by antagonizing its degradation and its inhibition could represent a therapeutic mechanism for abrogating cyclin E1 function in cancers. Cancer Res; 74(7); 2006–14. ©2014 AACR.
Data from Integrin αvβ6 Promotes an Osteolytic Program in Cancer Cells by Upregulating MMP2
Authors: Dutta Anindita , Li Jing , Lu Huimin , Akech Jacqueline , Pratap Jitesh , Wang Tao , Zerlanko Brad J. , FitzGerald Thomas J. , Jiang Zhong , Birbe Ruth , Wixted John , Violette Shelia M. , Stein Janet L. , Stein Gary S. , Lian Jane B. , Languino Lucia R.
Published: March 2024

Abstract
The molecular circuitries controlling osseous prostate metastasis are known to depend on the activity of multiple pathways, including integrin signaling. Here, we demonstrate that the αvβ6 integrin is upregulated in human prostate cancer bone metastasis. In prostate cancer cells, this integrin is a functionally active receptor for fibronectin and latency-associated peptide-TGF-β1; it mediates attachment and migration upon ligand binding and is localized in focal contacts. Given the propensity of prostate cancer cells to form bone metastatic lesions, we investigated whether the αvβ6 integrin promotes this type of metastasis. We show for the first time that αvβ6 selectively induces matrix metalloproteinase 2 (MMP2) in vitro in multiple prostate cancer cells and promotes osteolysis in vivo in an immunodeficient mouse model of bone metastasis through upregulation of MMP2, but not MMP9. The effect of αvβ6 on MMP2 expression and activity is independent of androgen receptor in the analyzed prostate cancer cells. Increased levels of parathyroid hormone–related protein (PTHrP), known to induce osteoclastogenesis, were also observed in αvβ6-expressing cells. However, by using MMP2 short hairpin RNA, we demonstrate that the αvβ6 effect on bone loss is due to upregulation of soluble MMP2 by the cancer cells, not due to changes in tumor growth rate. Another related αv-containing integrin, αvβ5, fails to show similar responses, underscoring the significance of αvβ6 activity. Overall, these mechanistic studies establish that expression of a single integrin, αvβ6, contributes to the cancer cell—mediated program of osteolysis by inducing matrix degradation through MMP2. Our results open new prospects for molecular therapy for metastatic bone disease. Cancer Res; 74(5); 1598–608. ©2014 AACR.
Data from Cofilin Drives Cell-Invasive and Metastatic Responses to TGF-β in Prostate Cancer
Authors: Collazo Joanne , Zhu Beibei , Larkin Spencer , Martin Sarah K. , Pu Hong , Horbinski Craig , Koochekpour Shahriar , Kyprianou Natasha
Published: March 2024

Abstract
Cofilin (CFL) is an F-actin–severing protein required for the cytoskeleton reorganization and filopodia formation, which drives cell migration. CFL binding and severing of F-actin is controlled by Ser3 phosphorylation, but the contributions of this step to cell migration during invasion and metastasis of cancer cells are unclear. In this study, we addressed the question in prostate cancer cells, including the response to TGF-β, a critical regulator of migration. In cells expressing wild-type CFL, TGF-β treatment increased LIMK-2 activity and cofilin phosphorylation, decreasing filopodia formation. Conversely, constitutively active CFL (SerAla) promoted filipodia formation and cell migration mediated by TGF-β. Notably, in cocultures of prostate cancer epithelial cells and cancer-associated fibroblasts, active CFL promoted invasive migration in response to TGF-β in the microenvironment. Further, constitutively active CFL elevated the metastatic ability of prostate cancer cells in vivo. We found that levels of active CFL correlated with metastasis in a mouse model of prostate tumor and that in human prostate cancer, CFL expression was increased significantly in metastatic tumors. Our findings show that the actin-severing protein CFL coordinates responses to TGF-β that are needed for invasive cancer migration and metastasis. Cancer Res; 74(8); 2362–73. ©2014 AACR.
Data from Increased Dietary Vitamin D Suppresses MAPK Signaling, Colitis, and Colon Cancer
Authors: Meeker Stacey , Seamons Audrey , Paik Jisun , Treuting Piper M. , Brabb Thea , Grady William M. , Maggio-Price Lillian
Published: March 2024

Abstract
Epidemiologic studies associate low serum vitamin D levels with an increased risk of colon cancer and inflammatory diseases such as inflammatory bowel disease (IBD). 129-Smad3tm1Par/J (Smad3−/−) mice are a model of bacteria-driven colitis and colon cancer when infected with Helicobacter bilis (H. bilis). Thus, we used this mouse model to determine whether increased dietary vitamin D would reduce inflammation and colon cancer. Smad3−/− mice were fed purified diet with either maintenance (1 IU vitamin D/g diet; maintenance) or increased concentrations of vitamin D (5 IU vitamin D/g diet; high vitamin D). One week after diet initiation, mice were inoculated with broth or H. bilis and were necropsied at several time points postinoculation to assess inflammation, dysplasia, and neoplasia incidence. At 16 weeks postinfection, 11% of mice fed high vitamin D diet had cancer compared with 41% of mice fed maintenance diet (P = 0.0121). Evaluation at an early time point (1 week postinfection) showed that animals fed high vitamin D had decreased MAPK (p-P38 and p-JNK) activation in lamina propria leukocytes as well as decreased NFκB activation in colonic epithelial cells. Reduction in MAPK and NFκB activation correlated with decreased IBD scores (2.7 vs. 15.5; P < 0.0001) as well as decreased inflammatory cell infiltrates and reduced expression of proinflammatory cytokines in cecal tissue. These findings suggest that increased dietary vitamin D is beneficial in preventing inflammation-associated colon cancer through suppression of inflammatory responses during initiation of neoplasia or early-stage carcinogenesis. Cancer Res; 74(16); 4398–408. ©2014 AACR.
Data from Apoptosis Imaging for Monitoring DR5 Antibody Accumulation and Pharmacodynamics in Brain Tumors Noninvasively
Authors: Weber Thomas G. , Osl Franz , Renner Anja , Pöschinger Thomas , Galbán Stefanie , Rehemtulla Alnawaz , Scheuer Werner
Published: March 2024

Abstract
High-grade gliomas often possess an impaired blood–brain barrier (BBB), which allows delivery of large molecules to brain tumors. However, achieving optimal drug concentrations in brain tumors remains a significant hurdle for treating patients successfully. Thus, detailed investigations of drug activities in gliomas are needed. To investigate BBB penetration, pharmacodynamics, and tumor retention kinetics of an agonistic DR5 antibody in a brain tumor xenograft model, we utilized a noninvasive imaging method for longitudinal monitoring of apoptosis induction. Brain tumors were induced by intracranial (i.c.) implantation of a luciferase-expressing tumor cell line as a reporter. To quantify accumulation of anti-DR5 in brain tumors, we generated a dosage–response curve for apoptosis induction after i.c. delivery of fluorescence-labeled anti-DR5 at different dosages. Assuming 100% drug delivery after i.c. application, the amount of accumulated antibody after i.v. application was calculated relative to its apoptosis induction. We found that up to 0.20% to 0.97% of antibody delivered i.v. reached the brain tumor, but that apoptosis induction declined quickly within 24 hours. These results were confirmed by three-dimensional fluorescence microscopy of antibody accumulation in explanted brains. Nonetheless, significant antitumor efficacy was documented after anti-DR5 delivery. We further demonstrated that antibody penetration was facilitated by an impaired BBB in brain tumors. These imaging methods enable the quantification of antibody accumulation and pharmacodynamics in brain tumors, offering a holistic approach for assessment of central nervous system–targeting drugs. Cancer Res; 74(7); 1913–23. ©2014 AACR.
Data from Identification of FoxR2 as an Oncogene in Medulloblastoma
Authors: Koso Hideto , Tsuhako Asano , Lyons Eli , Ward Jerrold M. , Rust Alistair G. , Adams David J. , Jenkins Nancy A. , Copeland Neal G. , Watanabe Sumiko
Published: March 2024

Abstract
Medulloblastoma is the most common pediatric brain tumor, and in ∼25% of cases, it is driven by aberrant activation of the Sonic Hedgehog (SHH) pathway in granule neuron precursor (GNP) cells. In this study, we identified novel medulloblastoma driver genes through a transposon mutagenesis screen in the developing brain of wild-type and Trp53 mutant mice. Twenty-six candidates were identified along with established driver genes such as Gli1 and Crebbp. The transcription factor FoxR2, the most frequent gene identified in the screen, is overexpressed in a small subset of human medulloblastoma of the SHH subtype. Tgif2 and Alx4, 2 new putative oncogenes identified in the screen, are strongly expressed in the SHH subtype of human medulloblastoma. Mutations in these two genes were mutually exclusive with mutations in Gli1 and tended to cooccur, consistent with involvement in the SHH pathway. Notably, Foxr2, Tgif2, and Alx4 activated Gli-binding sites in cooperation with Gli1, strengthening evidence that they function in SHH signaling. In support of an oncogenic function, Foxr2 overexpression transformed NIH3T3 cells and promoted proliferation of GNPs, the latter of which was also observed for Tgif2 and Alx4. These findings offer forward genetic and functional evidence associating Foxr2, Tgif2, and Alx4 with SHH subtype medulloblastoma. Cancer Res; 74(8); 2351–61. ©2014 AACR.
Data from MYCN-Dependent Expression of Sulfatase-2 Regulates Neuroblastoma Cell Survival
Authors: Solari Valeria , Borriello Lucia , Turcatel Gianluca , Shimada Hiroyuki , Sposto Richard , Fernandez G. Esteban , Asgharzadeh Shahab , Yates Edwin A. , Turnbull Jeremy E. , DeClerck Yves A.
Published: March 2024

Abstract
Heparan sulfate proteoglycans (HSPG) play a critical role in the interaction of tumor cells and their microenvironment. HSPG activity is dictated by sulfation patterns controlled by sulfotransferases, which add sulfate groups, and sulfatases (Sulf), which remove 6-O-sulfates. Here, we report altered expression of these enzymes in human neuroblastoma cells with higher levels of Sulf-2 expression, a specific feature of MYCN-amplified cells (MYCN-A cells) that represent a particularly aggressive subclass. Sulf-2 overexpression in neuroblastoma cells lacking MYCN amplification (MYCN-NA cells) increased their in vitro survival. Mechanistic investigations revealed evidence of a link between Sulf-2 expression and MYCN pathogenicity in vitro and in vivo. Analysis of Sulf-2 protein expression in 65 human neuroblastoma tumors demonstrated a higher level of Sulf-2 expression in MYCN-A tumors than in MYCN-NA tumors. In two different patient cohorts, we confirmed the association in expression patterns of Sulf-2 and MYCN and determined that Sulf-2 overexpression predicted poor outcomes in a nonindependent manner with MYCN. Our findings define Sulf-2 as a novel positive regulator of neuroblastoma pathogenicity that contributes to MYCN oncogenicity. Cancer Res; 74(21); 5999–6009. ©2014 AACR.
Data from A Common Cancer-Associated DNA Polymerase ϵ Mutation Causes an Exceptionally Strong Mutator Phenotype, Indicating Fidelity Defects Distinct from Loss of Proofreading
Authors: Kane Daniel P. , Shcherbakova Polina V.
Published: March 2024

Abstract
Exonucleolytic proofreading and DNA mismatch repair (MMR) act in series to maintain high-fidelity DNA replication and to avoid mutagenesis. MMR defects elevate the overall mutation rate and are associated with increased cancer incidence. Hypermutable colorectal and endometrial tumors with functional MMR were recently reported to carry amino acid substitutions in the exonuclease domain of DNA polymerase ϵ (Polϵ). This created a notion that loss of the proofreading activity of Polϵ is an initiating cause of some sporadic human cancers. In this study, we identified a somatic P286R substitution in the conserved ExoI motif of Polϵ in a collection of 52 sporadic colorectal tumor specimens. This change has been repeatedly observed in colorectal and endometrial tumors in previous studies despite many possible ways to inactivate Polϵ proofreading. To understand the reasons for the recurrent appearance of the P286R variant, we characterized its functional consequences using the yeast model system. An analogous substitution in the yeast Polϵ produced an unusually strong mutator phenotype exceeding that of proofreading-deficient mutants by two orders of magnitude. This argues that the P286R mutation acts at some level other than loss of exonuclease to elevate cancer risk. Heterozygosity for the variant allele caused a strong mutator effect comparable with that of complete MMR deficiency, providing an explanation for why loss of heterozygosity is not required for the development of Polϵ-mutant human tumors. Cancer Res; 74(7); 1895–901. ©2014 AACR.
Data from p53 and NF-κB Coregulate Proinflammatory Gene Responses in Human Macrophages
Authors: Lowe Julie M. , Menendez Daniel , Bushel Pierre R. , Shatz Maria , Kirk Erin L. , Troester Melissa A. , Garantziotis Stavros , Fessler Michael B. , Resnick Michael A.
Published: March 2024

Abstract
Macrophages are sentinel immune cells that survey the tissue microenvironment, releasing cytokines in response to both exogenous insults and endogenous events such as tumorigenesis. Macrophages mediate tumor surveillance and therapy-induced tumor regression; however, tumor-associated macrophages (TAM) and their products may also promote tumor progression. Whereas NF-κB is prominent in macrophage-initiated inflammatory responses, little is known about the role of p53 in macrophage responses to environmental challenge, including chemotherapy or in TAMs. Here, we report that NF-κB and p53, which generally have opposing effects in cancer cells, coregulate induction of proinflammatory genes in primary human monocytes and macrophages. Using Nutlin-3 as a tool, we demonstrate that p53 and NF-κB rapidly and highly induce interleukin (IL)-6 by binding to its promoter. Transcriptome analysis revealed global p53/NF-κB co-regulation of immune response genes, including several chemokines, which effectively induced human neutrophil migration. In addition, we show that p53, activated by tumor cell paracrine factors, induces high basal levels of macrophage IL-6 in a TAM model system [tumor-conditioned macrophages (TCM)]. Compared with normal macrophages, TCMs exhibited higher p53 levels, enhanced p53 binding to the IL-6 promoter, and reduced IL-6 levels upon p53 inhibition. Taken together, we describe a mechanism by which human macrophages integrate signals through p53 and NF-κB to drive proinflammatory cytokine induction. Our results implicate a novel role for macrophage p53 in conditioning the tumor microenvironment and suggest a potential mechanism by which p53-activating chemotherapeutics, acting upon p53-sufficient macrophages and precursor monocytes, may indirectly impact tumors lacking functional p53. Cancer Res; 74(8); 2182–92. ©2014 AACR.
Data from A Macrophage-Specific Fluorescent Probe for Intraoperative Lymph Node Staging
Authors: Yoo Jung Sun , Lee Sung-Chan , Jow Zhi Yen , Koh Pamela Yun Xiang , Chang Young-Tae
Published: March 2024

Abstract
Successful identification of nodal metastases in patients with cancer is crucial to prescribe suitable treatment regimens that can improve recurrence-free survival. Although some new imaging technologies for nodal staging have been developed, such as nanoparticle-enhanced MRI and quantum-dot–based fluorescence imaging, sound technologies for intraoperative differentiation of metastatic and inflamed lymph nodes remain lacking. In this study, we illustrate the feasibility of using a macrophage-specific fluorescent probe (MFP) to visualize sentinel lymph nodes during surgery, highlighting abnormalities related to inflammation and tumor infiltration with signal enhancement and reduction methods using this technology. MFP was identified by high-throughput screening of fluorescent small-molecule libraries synthesized with a diversity-oriented approach. It selectively visualized monocyte and macrophage cell populations in vitro, by live-cell imaging and flow cytometry, as well as in vivo, for imaging-guided surgery. Collectively, this study provides preclinical proof of concept for an intraoperative imaging platform to accurately assess lymph node status, eliminating the need for invasive nodal dissections that can contribute to complications of cancer therapy. Cancer Res; 74(1); 44–55. ©2013 AACR.
Data from Endothelial-Specific Notch Blockade Inhibits Vascular Function and Tumor Growth through an eNOS-Dependent Mechanism
Authors: Patenaude Alexandre , Fuller Megan , Chang Linda , Wong Fred , Paliouras Grigorios , Shaw Rebecca , Kyle Alastair H. , Umlandt Patricia , Baker Jennifer H.E. , Diaz Erika , Tong Jade , Minchinton Andrew I. , Karsan Aly
Published: March 2024

Abstract
Notch signaling is important for tumor angiogenesis induced by vascular endothelial growth factor A. Blockade of the Notch ligand Dll4 inhibits tumor growth in a paradoxical way. Dll4 inhibition increases endothelial cell sprouting, but vessels show reduced perfusion. The reason for this lack of perfusion is not currently understood. Here we report that inhibition of Notch signaling in endothelial cell using an inducible binary transgenic system limits VEGFA-driven tumor growth and causes endothelial dysfunction. Neither excessive endothelial cell sprouting nor defects of pericyte abundance accompanied the inhibition of tumor growth and functional vasculature. However, biochemical and functional analysis revealed that endothelial nitric oxide production is decreased by Notch inhibition. Treatment with the soluble guanylate cyclase activator BAY41-2272, a vasorelaxing agent that acts downstream of endothelial nitric oxide synthase (eNOS) by directly activating its soluble guanylyl cyclase receptor, rescued blood vessel function and tumor growth. We show that reduction in nitric oxide signaling is an early alteration induced by Notch inhibition and suggest that lack of functional vessels observed with Notch inhibition is secondary to inhibition of nitric oxide signaling. Coculture and tumor growth assays reveal that Notch-mediated nitric oxide production in endothelial cell requires VEGFA signaling. Together, our data support that eNOS inhibition is responsible for the tumor growth and vascular function defects induced by endothelial Notch inhibition. This study uncovers a novel mechanism of nitric oxide production in endothelial cells in tumors, with implications for understanding the peculiar character of tumor blood vessels. Cancer Res; 74(9); 2402–11. ©2014 AACR.
Data from CXM: A New Tool for Mapping Breast Cancer Risk in the Tumor Microenvironment
Authors: Flister Michael J. , Endres Bradley T. , Rudemiller Nathan , Sarkis Allison B. , Santarriaga Stephanie , Roy Ishan , Lemke Angela , Geurts Aron M. , Moreno Carol , Ran Sophia , Tsaih Shirng-Wern , De Pons Jeffery , Carlson Daniel F. , Tan Wenfang , Fahrenkrug Scott C. , Lazarova Zelmira , Lazar Jozef , North Paula E. , LaViolette Peter S. , Dwinell Michael B. , Shull James D. , Jacob Howard J.
Published: March 2024

Abstract
The majority of causative variants in familial breast cancer remain unknown. Of the known risk variants, most are tumor cell autonomous, and little attention has been paid yet to germline variants that may affect the tumor microenvironment. In this study, we developed a system called the Consomic Xenograft Model (CXM) to map germline variants that affect only the tumor microenvironment. In CXM, human breast cancer cells are orthotopically implanted into immunodeficient consomic strains and tumor metrics are quantified (e.g., growth, vasculogenesis, and metastasis). Because the strain backgrounds vary, whereas the malignant tumor cells do not, any observed changes in tumor progression are due to genetic differences in the nonmalignant microenvironment. Using CXM, we defined genetic variants on rat chromosome 3 that reduced relative tumor growth and hematogenous metastasis in the SS.BN3IL2Rγ consomic model compared with the SSIL2Rγ parental strain. Paradoxically, these effects occurred despite an increase in the density of tumor-associated blood vessels. In contrast, lymphatic vasculature and lymphogenous metastasis were unaffected by the SS.BN3IL2Rγ background. Through comparative mapping and whole-genome sequence analysis, we narrowed candidate variants on rat chromosome 3 to six genes with a priority for future analysis. Collectively, our results establish the utility of CXM to localize genetic variants affecting the tumor microenvironment that underlie differences in breast cancer risk. Cancer Res; 74(22); 6419–29. ©2014 AACR.
Data from High Fidelity Patient-Derived Xenografts for Accelerating Prostate Cancer Discovery and Drug Development
Authors: Lin Dong , Wyatt Alexander W. , Xue Hui , Wang Yuwei , Dong Xin , Haegert Anne , Wu Rebecca , Brahmbhatt Sonal , Mo Fan , Jong Lina , Bell Robert H. , Anderson Shawn , Hurtado-Coll Antonio , Fazli Ladan , Sharma Manju , Beltran Himisha , Rubin Mark , Cox Michael , Gout Peter W. , Morris James , Goldenberg Larry , Volik Stanislav V. , Gleave Martin E. , Collins Colin C. , Wang Yuzhuo
Published: March 2024

Abstract
Standardized and reproducible preclinical models that recapitulate the dynamics of prostate cancer are urgently needed. We established a bank of transplantable patient-derived prostate cancer xenografts that capture the biologic and molecular heterogeneity currently confounding prognostication and therapy development. Xenografts preserved the histopathology, genome architecture, and global gene expression of donor tumors. Moreover, their aggressiveness matched patient observations, and their response to androgen withdrawal correlated with tumor subtype. The panel includes the first xenografts generated from needle biopsy tissue obtained at diagnosis. This advance was exploited to generate independent xenografts from different sites of a primary site, enabling functional dissection of tumor heterogeneity. Prolonged exposure of adenocarcinoma xenografts to androgen withdrawal led to castration-resistant prostate cancer, including the first-in-field model of complete transdifferentiation into lethal neuroendocrine prostate cancer. Further analysis of this model supports the hypothesis that neuroendocrine prostate cancer can evolve directly from adenocarcinoma via an adaptive response and yielded a set of genes potentially involved in neuroendocrine transdifferentiation. We predict that these next-generation models will be transformative for advancing mechanistic understanding of disease progression, response to therapy, and personalized oncology. Cancer Res; 74(4); 1272–83. ©2013 AACR.
Data from UTX and MLL4 Coordinately Regulate Transcriptional Programs for Cell Proliferation and Invasiveness in Breast Cancer Cells
Authors: Kim Jae-Hwan , Sharma Amrish , Dhar Shilpa S. , Lee Sung-Hun , Gu Bingnan , Chan Chia-Hsin , Lin Hui-Kuan , Lee Min Gyu
Published: March 2024

Abstract
Histone methyltransferases and demethylases reversibly modulate histone lysine methylation, which is considered a key epigenetic mark associated with gene regulation. Recently, aberrant regulation of gene expression by histone methylation modifiers has emerged as an important mechanism for tumorigenesis. However, it remains largely unknown how histone methyltransferases and demethylases coregulate transcriptional profiles for cancer cell characteristics. Here, we show that in breast cancer cells, the histone H3 lysine 27 (H3K27) demethylase UTX (also known as KDM6A) positively regulates gene expression programs associated with cell proliferation and invasion. The majority of UTX-controlled genes, including a cohort of oncogenes and prometastatic genes, are coregulated by the H3K4 methyltransferase mixed lineage leukemia 4 (MLL4, also called ALR, KMT2D, and MLL2). UTX interacted with a C-terminal region of MLL4. UTX knockdown resulted in significant decreases in the proliferation and invasiveness of breast cancer cells in vitro and in a mouse xenograft model. Such defective cellular characteristics of UTX-depleted cells were phenocopied by MLL4 knockdown cells. UTX-catalyzed demethylation of trimethylated H3K27 and MLL4-mediated trimethylation at H3K4 occurred interdependently at cotarget genes of UTX and MLL4. Clinically, high levels of UTX or MLL4 were associated with poor prognosis in patients with breast cancer. Taken together, these findings uncover that coordinated regulation of gene expression programs by a histone methyltransferase and a histone demethylase is coupled to the proliferation and invasion of breast cancer cells. Cancer Res; 74(6); 1705–17. ©2014 AACR.
Data from Identification of a Cyclin D1 Network in Prostate Cancer That Antagonizes Epithelial–Mesenchymal Restraint
Authors: Ju Xiaoming , Casimiro Mathew C. , Gormley Michael , Meng Hui , Jiao Xuanmao , Katiyar Sanjay , Crosariol Marco , Chen Ke , Wang Min , Quong Andrew A. , Lisanti Michael P. , Ertel Adam , Pestell Richard G.
Published: March 2024

Abstract
Improved clinical management of prostate cancer has been impeded by an inadequate understanding of molecular genetic elements governing tumor progression. Gene signatures have provided improved prognostic indicators of human prostate cancer. The TGF-β/BMP-SMAD4 signaling pathway, which induces epithelial–mesenchymal transition (EMT), is known to constrain prostate cancer progression induced by Pten deletion. Herein, cyclin D1 inactivation reduced cellular proliferation in the murine prostate in vivo and in isogenic oncogene–transformed prostate cancer cell lines. The in vivo cyclin D1–mediated molecular signature predicted poor outcome of recurrence-free survival for patients with prostate cancer (K-means HR, 3.75, P = 0.02) and demonstrated that endogenous cyclin D1 restrains TGF-β, Snail, Twist, and Goosecoid signaling. Endogenous cyclin D1 enhanced Wnt and ES cell gene expression and expanded a prostate stem cell population. In chromatin immunoprecipitation sequencing, cyclin D1 occupied genes governing stem cell expansion and induced their transcription. The coordination of EMT restraining and stem cell expanding gene expression by cyclin D1 in the prostate may contribute to its strong prognostic value for poor outcome in biochemical-free recurrence in human prostate cancer. Cancer Res; 74(2); 508–19. ©2013 AACR.
Data from DDB2: A Novel Regulator of NF-κB and Breast Tumor Invasion
Authors: Ennen Marie , Klotz Rémi , Touche Nadège , Pinel Sophie , Barbieux Claire , Besancenot Vanessa , Brunner Emilie , Thiebaut Denise , Jung Alain C. , Ledrappier Sonia , Domenjoud Lionel , Abecassis Joseph , Plénat François , Grandemange Stéphanie , Becuwe Philippe
Published: March 2024

Abstract
The DNA repair protein damaged DNA-binding 2 (DDB2) has been implicated in promoting cell-cycle progression by regulating gene expression. DDB2 is selectively overexpressed in breast tumor cells that are noninvasive, but not in those that are invasive. We found that its overexpression in invasive human breast tumor cells limited their motility and invasiveness in vitro and blocked their ability to colonize lungs in vivo, defining a new function for DDB2 in malignant progression. DDB2 overexpression attenuated the activity of NF-κB and the expression of its target matrix metalloprotease 9 (MMP9). Mechanistic investigations indicated that DDB2 decreased NF-κB activity by upregulating expression of IκBα by binding the proximal promoter of this gene. This effect was causally linked to invasive capacity. Indeed, knockdown of DDB2-induced IκBα gene expression restored NF-κB activity and MMP9 expression, along with the invasive properties of breast tumor cells overexpressing DDB2. Taken together, our findings enlighten understanding of how breast cancer cells progress to an invasive phenotype and underscore potential clinical interest in DDB2 as a prognostic marker or therapeutic target in this setting. Cancer Res; 73(16); 5040–52. ©2013 AACR.
Data from Invasive Lobular Carcinoma Cell Lines Are Characterized by Unique Estrogen-Mediated Gene Expression Patterns and Altered Tamoxifen Response
Authors: Sikora Matthew J. , Cooper Kristine L. , Bahreini Amir , Luthra Soumya , Wang Guoying , Chandran Uma R. , Davidson Nancy E. , Dabbs David J. , Welm Alana L. , Oesterreich Steffi
Published: March 2024

Abstract
Invasive lobular carcinoma (ILC) is a histologic subtype of breast cancer that is frequently associated with favorable outcomes, as approximately 90% of ILC express the estrogen receptor (ER). However, recent retrospective analyses suggest that patients with ILC receiving adjuvant endocrine therapy may not benefit as much as patients with invasive ductal carcinoma. On the basis of these observations, we characterized ER function and endocrine response in ILC models. The ER-positive ILC cell lines MDA MB 134VI (MM134) and SUM44PE were used to examine the ER-regulated transcriptome via gene expression microarray analyses and ER ChIP-Seq, and to examine response to endocrine therapy. In parallel, estrogen response was assessed in vivo in the patient-derived ILC xenograft HCI-013. We identified 915 genes that were uniquely E2 regulated in ILC cell lines versus other breast cancer cell lines, and a subset of these genes were also E2 regulated in vivo in HCI-013. MM134 cells were de novo tamoxifen resistant and were induced to grow by 4-hydroxytamoxifen, as well as other antiestrogens, as partial agonists. Growth was accompanied by agonist activity of tamoxifen on ER-mediated gene expression. Though tamoxifen induced cell growth, MM134 cells required fibroblast growth factor receptor (FGFR)-1 signaling to maintain viability and were sensitive to combined endocrine therapy and FGFR1 inhibition. Our observation that ER drives a unique program of gene expression in ILC cells correlates with the ability of tamoxifen to induce growth in these cells. Targeting growth factors using FGFR1 inhibitors may block survival pathways required by ILC and reverse tamoxifen resistance. Cancer Res; 74(5); 1463–74. ©2014 AACR.