bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Stem Cell–like Glioma Cells Promote Tumor Angiogenesis through Vascular Endothelial Growth Factor
Authors: Bao Shideng , Wu Qiulian , Sathornsumetee Sith , Hao Yueling , Li Zhizhong , Hjelmeland Anita B. , Shi Qing , McLendon Roger E. , Bigner Darell D. , Rich Jeremy N.
Published: March 2023

Abstract
Malignant gliomas are highly lethal cancers dependent on angiogenesis. Critical tumor subpopulations within gliomas share characteristics with neural stem cells. We examined the potential of stem cell–like glioma cells (SCLGC) to support tumor angiogenesis. SCLGC isolated from human glioblastoma biopsy specimens and xenografts potently generated tumors when implanted into the brains of immunocompromised mice, whereas non-SCLGC tumor cells isolated from only a few tumors formed secondary tumors when xenotransplanted. Tumors derived from SCLGC were morphologically distinguishable from non-SCLGC tumor populations by widespread tumor angiogenesis, necrosis, and hemorrhage. To determine a potential molecular mechanism for SCLGC in angiogenesis, we measured the expression of a panel of angiogenic factors secreted by SCLGC. In comparison with matched non-SCLGC populations, SCLGC consistently secreted markedly elevated levels of vascular endothelial growth factor (VEGF), which were further induced by hypoxia. In an in vitro model of angiogenesis, SCLGC-conditioned medium significantly increased endothelial cell migration and tube formation compared with non-SCLGC tumor cell–conditioned medium. The proangiogenic effects of glioma SCLGC on endothelial cells were specifically abolished by the anti-VEGF neutralizing antibody bevacizumab, which is in clinical use for cancer therapy. Furthermore, bevacizumab displayed potent antiangiogenic efficacy in vivo and suppressed growth of xenografts derived from SCLGC but limited efficacy against xenografts derived from a matched non-SCLGC population. Together these data indicate that stem cell–like tumor cells can be a crucial source of key angiogenic factors in cancers and that targeting proangiogenic factors from stem cell–like tumor populations may be critical for patient therapy. (Cancer Res 2006; 66(16): 7843-8)
Data from Differentiation of Androgen-Independent Prostate Cancer PC-3 Cells Is Associated with Increased Nuclear Factor-κB Activity
Authors: Floryk Daniel , Huberman Eliezer
Published: March 2023

Abstract
Recently, we have reported that inosine 5′-monophosphate dehydrogenase inhibitors, such as mycophenolic acid (MPA), induce the differentiation of PC-3 cells, which are derived from a human androgen-independent prostate cancer, into cells with a phenotype resembling maturing prostate secretory cells. Here, we describe such differentiation induced by the histone deacetylase inhibitor tributyrin. The maturation was defined by cytoplasmic vacuole production and induction of CD10, CD46, CD55, GRP78, keratin 17, and zinc-α-2-glycoprotein. To identify additional genes associated with tributyrin-induced PC-3 cell differentiation and to gain some insight into the mechanism that underlies this differentiation, we have, by means of microarray analyses, compared tributyrin-induced gene expression patterns with those of MPA, which initiates PC-3 cell differentiation by a dissimilar mode of action. We suggested that genes induced by both tributyrin and MPA would be most likely associated with differentiation rather than with the unique action of each particular inducer. Our results indicated that tributyrin or MPA induced the expression of a large number of common genes, including genes known or assumed to be NF-κB dependent. The NF-κB dependency of a group of these genes, which included the PC-3 cell differentiation marker keratin 17, was confirmed by using two common NF-κB activation inhibitors, Bay11-082 and TMB-8, and p65 subunit of NF-κB complex specific small interfering RNA. Taken together, our results implicate both NF-κB–dependent and NF-κB–independent genes in the processes leading to PC-3 cell differentiation induced by tributyrin and MPA. (Cancer Res 2005; 65(24): 11588-96)
Data from Identification and Functional Characterization of a Novel Unspliced Transcript Variant of HIC-1 in Human Cancer Cells Exposed to Adverse Growth Conditions
Authors: Mondal Abdul Matin , Chinnadurai Sivasamy , Datta Kamal , Chauhan Shyam S. , Sinha Subrata , Chattopadhyay Parthaprasad
Published: March 2023

Abstract
The wild-type p53 gene has been widely implicated in the regulation of hypermethylated in cancer-1 (HIC-1) transcription, a master growth regulatory gene with multiple promoters and, consequently, multiple alternatively spliced transcripts. We investigated the role of p53 (wild type and mutant, both endogenous and exogenous) in modulating the various HIC-1 transcripts. We discovered a novel unspliced HIC-1 transcript, identified as “f” in leukocytes and in the human cell lines U87MG (wild-type p53), U373MG (mutant p53), MCF-7 (wild-type p53), HeLa (p53 degraded by HPV18-E6 oncoprotein), and Saos-2 (p53 null). This transcript is initiated from a new transcription start site and has an intervening stop codon that would result in a possibly truncated 22-amino-acid polypeptide. When U87MG (wild-type p53) and MCF-7 cells (wild-type p53) were exposed to adverse growth conditions of serum starvation or treated with the chemotherapeutic agent cisplatin, cells underwent apoptosis and cell cycle arrest accompanied by increase in p53 and HIC-1 transcript levels. Although the increase of the HIC-1-spliced transcripts followed the increase of p53, increase in f transcript coincided with declining p53 and HIC-1 transcript and protein levels. Moreover, the levels of HIC-1 f transcript were not induced by exogenously transfected wild-type p53 in p53-mutated U373MG and p53-null Saos-2 cells, unlike the spliced transcripts that code for full-length HIC-1 protein. These findings suggest a working model wherein the status of f transcript, which is not under direct transcriptional control of wild-type p53, may influence the level of HIC-1 protein in cancer cells. (Cancer Res 2006; 66(21): 10466-77)
Data from Gene Expression Profiles Identify Epithelial-to-Mesenchymal Transition and Activation of Nuclear Factor-κB Signaling as Characteristics of a High-risk Head and Neck Squamous Cell Carcinoma
Authors: Chung Christine H. , Parker Joel S. , Ely Kim , Carter Jesse , Yi Yajun , Murphy Barbara A. , Ang K. Kian , El-Naggar Adel K. , Zanation Adam M. , Cmelak Anthony J. , Levy Shawn , Slebos Robbert J. , Yarbrough Wendell G.
Published: March 2023

Abstract
Gene expression signatures generated from DNA microarray analyses have shown promise as predictive biomarkers of clinical outcome. In this study, we determined a high-risk signature for disease recurrence using formalin-fixed head and neck squamous cell carcinoma (HNSCC) tumors and compared the results with an independent data set obtained from fresh frozen tumors. We also showed that genes involved in epithelial-to-mesenchymal transition (EMT) and nuclear factor-κB (NF-κB) signaling deregulation are the most prominent molecular characteristics of the high-risk tumors. Gene expression was determined in 40 samples, including 34 formalin-fixed tissues and 6 matched frozen tissues, from 29 HNSCC patients. A 75-gene list predictive of disease recurrence was determined by training on the formalin-fixed tumor data set and tested on data from the independent frozen tumor set from 60 HNSCC patients. The difference in recurrence-free survival (RFS) between the high-risk versus low-risk groups in the training and test sets was statistically significant (P = 0.002 and 0.03, respectively, log-rank test). In addition, the gene expression data was interrogated using Gene Set Enrichment Analysis to determine biological significance. The most significant sets of genes enriched in the high-risk tumors were genes involving EMT, NF-κB activation, and cell adhesion. In conclusion, global gene expression analysis is feasible using formalin-fixed tissue. The 75-gene list can be used as a prognostic biomarker of recurrence, and our data suggest that the molecular determinants of EMT and NF-κB activation can be targeted as the novel therapy in the identified high-risk patients. (Cancer Res 2006; 66(16): 8210-8)
Data from Loss of Phosphatase and Tensin Homologue Increases Transforming Growth Factor β–Mediated Invasion with Enhanced SMAD3 Transcriptional Activity
Authors: Hjelmeland Anita B. , Hjelmeland Mark D. , Shi Qing , Hart Janet L. , Bigner Darell D. , Wang Xiao-Fan , Kontos Christopher D. , Rich Jeremy N.
Published: March 2023

Abstract
In normal epithelial tissues, the multifunctional cytokine transforming growth factor-β (TGF-β) acts as a tumor suppressor through growth inhibition and induction of differentiation whereas in advanced cancers, TGF-β promotes tumor progression through induction of tumor invasion, neoangiogenesis, and immunosuppression. The molecular mechanisms through which TGF-β shifts from a tumor suppressor to a tumor enhancer are poorly understood. We now show a role for the tumor suppressor phosphatase and tensin homologue deleted on chromosome 10 (PTEN) in repressing the protumorigenic effects of TGF-β. The TGF-β effector SMAD3 inducibly interacts with PTEN on TGF-β treatment under endogenous conditions. RNA interference (RNAi) suppression of PTEN expression enhances SMAD3 transcriptional activity and TGF-β–mediated induction of SMAD3 target genes whereas reconstitution of PTEN in a null cancer cell line represses the expression of TGF-β–regulated target genes. Targeting PTEN expression through RNAi in a PTEN wild-type cell line increases TGF-β–mediated invasion but does not affect TGF-β–mediated growth inhibition. Reconstitution of PTEN expression in a PTEN-null cell line blocks TGF-β–induced invasion but does not modulate TGF-β–mediated growth regulation. These effects are distinct from Akt and Forkhead family members that also interact with SMAD3 to regulate apoptosis or proliferation, respectively. Pharmacologic inhibitors targeting TGF-β receptors and phosphatidylinositol 3-kinase signaling downstream from PTEN cooperate to block TGF-β–mediated invasion. Thus, the loss of PTEN expression in human cancers may contribute to a role for TGF-β as a tumor enhancer with specific effects on cellular motility and invasion. (Cancer Res 2005; 65(24): 11276-81)
Data from Constitutive Expression and Costimulatory Function of LIGHT/TNFSF14 on Human Melanoma Cells and Melanoma-Derived Microvesicles
Authors: Mortarini Roberta , Scarito Alessia , Nonaka Daisuke , Zanon Marina , Bersani Ilaria , Montaldi Elisabetta , Pennacchioli Elisabetta , Patuzzo Roberto , Santinami Mario , Anichini Andrea
Published: March 2023

Abstract
Neoplastic cells are thought to have defective expression of costimulatory molecules. However, in this study, we show that human melanoma cells express LIGHT/TNFSF14, a ligand of herpesvirus entry mediator on T cells and of lymphotoxin β receptor on stromal cells. In vitro, melanoma cells stained for LIGHT in the intracellular compartment, with weak or negative cell surface expression. However, LIGHT was expressed on tumor-derived microvesicles released from melanoma cells. In vivo, LIGHT was found in metastatic lesions, and the extent of lymphotoxin β receptor expression on the stromal cells was significantly associated with a “brisk” T-cell infiltrate in the neoplastic tissue. In the lesions with a brisk T-cell infiltrate, stromal cells surrounding the tumor also stained for the T-cell attractant chemokine CCL21. The intratumoral T lymphocytes frequently expressed herpesvirus entry mediator and were characterized by a differentiated phenotype. Coculture of lymphocytes with LIGHT+ melanoma-derived microvesicles or even with LIGHT+ melanoma cells in the presence of interleukin-2 costimulated LIGHT-dependent CD3+CD8+ T-cell proliferation. However, lymphocyte coculture with LIGHT+ microvesicles in the presence of interleukin-2 was also associated with an apoptotic response as documented by increased binding of Annexin V by CD3+CD8+ T cells. These data suggest that LIGHT constitutively expressed in human melanoma cells and microvesicles may contribute to regulate T-cell responses to tumor cells.
Data from Deletion of the COOH-Terminal Domain of CXC Chemokine Receptor 4 Leads to the Down-regulation of Cell-to-Cell Contact, Enhanced Motility and Proliferation in Breast Carcinoma Cells
Authors: Ueda Yukiko , Neel Nicole F. , Schutyser Evemie , Raman Dayanidhi , Richmond Ann
Published: March 2023

Abstract
The CXC chemokine receptor 4 (CXCR4) contributes to the metastasis of human breast cancer cells. The CXCR4 COOH-terminal domain (CTD) seems to play a major role in regulating receptor desensitization and down-regulation. We expressed either wild-type CXCR4 (CXCR4-WT) or CTD-truncated CXCR4 (CXCR4-ΔCTD) in MCF-7 human mammary carcinoma cells to determine whether the CTD is involved in CXCR4-modulated proliferation of mammary carcinoma cells. CXCR4-WT-transduced MCF-7 cells (MCF-7/CXCR4-WT cells) do not differ from vector-transduced MCF-7 control cells in morphology or growth rate. However, CXCR4-ΔCTD-transduced MCF-7 cells (MCF-7/CXCR4-ΔCTD cells) exhibit a higher growth rate and altered morphology, potentially indicating an epithelial-to-mesenchymal transition. Furthermore, extracellular signal-regulated kinase (ERK) activation and cell motility are increased in these cells. Ligand induces receptor association with β-arrestin for both CXCR4-WT and CXCR4-ΔCTD in these MCF-7 cells. Overexpressed CXCR4-WT localizes predominantly to the cell surface in unstimulated cells, whereas a significant portion of overexpressed CXCR4-ΔCTD resides intracellularly in recycling endosomes. Analysis with human oligomicroarray, Western blot, and immunohistochemistry showed that E-cadherin and Zonula occludens are down-regulated in MCF-7/CXCR4-ΔCTD cells. The array analysis also indicates that mesenchymal marker proteins and certain growth factor receptors are up-regulated in MCF-7/CXCR4-ΔCTD cells. These observations suggest that (a) the overexpression of CXCR4-ΔCTD leads to a gain-of-function of CXCR4-mediated signaling and (b) the CTD of CXCR4-WT may perform a feedback repressor function in this signaling pathway. These data will contribute to our understanding of how CXCR4-ΔCTD may promote progression of breast tumors to metastatic lesions. (Cancer Res 2006; 66(11): 5665-75)
Data from Antitumor Activity of an Oncolytic Adenovirus-Delivered Oncogene Small Interfering RNA
Authors: Zhang Yu-An , Nemunaitis John , Samuel Shirley K. , Chen Patrick , Shen Yuqiao , Tong Alex W.
Published: March 2023

Abstract
Despite successes in animal models, cancer gene therapy with small interfering RNAs (siRNA) is hindered by the lack of an optimal delivery platform. We examined the applicability of the replication-competent, oncolytic adenovirus, ONYX-411, to deliver a mutant K-ras siRNA transgene to human cancer cells. Proof-of-principle studies showed an additive tumor growth–inhibitory response through siRNA-mediated K-ras knockdown and ONYX-411-mediated cancer cell lysis. A novel construct, termed Internavec (for interfering RNA vector), was generated by cloning a K-rasv12-specific siRNAras-4 hairpin construct under the control of the human H1 promoter into the deleted E3b region of ONYX-411. Internavec acquired an increase in potency of ∼10-fold in human cancer cells expressing the relevant K-rasv12 mutation (H79, H441, and SW480), as defined by a reduction in the effective dose needed to achieve 50% growth inhibition (ED50). Internavec remained attenuated in nonmalignant epithelial cells. Daily intratumoral injections of Internavec (five daily injections of 1 × 108 plaque-forming units) significantly reduced the growth of s.c. H79 pancreatic cancer xenografts in nu/nu mice by 85.5%, including complete growth suppression in three of five mice. Parental ONYX-411 or ONYX-411-siRNAGFP was markedly less effective (47.8% growth reduction, P = 0.03; and 44.1% growth reduction, P = 0.03, respectively). siRNAras transgene activity contributed to cell cycle blockage, increased apoptosis, and marked down-regulation of Ras signaling–related gene expression (AKT2, GSK3β, E2F2, and MAP4K5). These findings indicate that Internavec can generate a two-pronged attack on tumor cells through oncogene knockdown and viral oncolysis, resulting in a significantly enhanced antitumor outcome. (Cancer Res 2006; 66(19): 9736-43)
Data from Activator Protein-1 Activity Regulates Epithelial Tumor Cell Identity
Authors: Gerdes Michael J. , Myakishev Maxim , Frost Nicholas A. , Rishi Vikas , Moitra Jaideep , Acharya Asha , Levy Michelle R. , Park Sang-won , Glick Adam , Yuspa Stuart H. , Vinson Charles
Published: March 2023

Abstract
To examine the consequences of inhibiting activator protein-1 (AP-1) transcription factors in skin, transgenic mice were generated, which use the tetracycline system to conditionally express A-FOS, a dominant negative that inhibits AP-1 DNA binding. Older mice develop mild alopecia and hyperplasia of sebaceous glands, particularly around the eyes. When A-FOS was expressed during chemical-induced skin carcinogenesis, mice do not develop characteristic benign and malignant squamous lesions but instead develop benign sebaceous adenomas containing a signature mutation in the H-ras proto-oncogene. Inhibiting AP-1 activity after tumor formation caused squamous tumors to transdifferentiate into sebaceous tumors. Furthermore, reactivating AP-1 in sebaceous tumors results in a reciprocal transdifferentiation into squamous tumors. In both cases of transdifferentiation, individual cells express molecular markers for both cell types, indicating individual tumor cells have the capacity to express multiple lineages. Molecular characterization of cultured keratinocytes and tumor material indicates that AP-1 regulates the balance between the wnt/β-catenin and hedgehog signaling pathways that determine squamous and sebaceous lineages, respectively. Chromatin immunoprecipitation analysis indicates that c-Jun binds several wnt promoters, which are misregulated by A-FOS expression, suggesting that members of the wnt pathway can be a primary targets of AP-1 transcriptional regulation. Thus, AP-1 activity regulates tumor cell lineage and is essential to maintain the squamous tumor cell identity. (Cancer Res 2006; 66(15): 7578-88)
Data from A1 Adenosine Receptors in Microglia Control Glioblastoma-Host Interaction
Authors: Synowitz Michael , Glass Rainer , Färber Katrin , Markovic Darko , Kronenberg Golo , Herrmann Ken , Schnermann Juergen , Nolte Christiane , van Rooijen Nico , Kiwit Juergen , Kettenmann Helmut
Published: March 2023

Abstract
We report that experimental glioblastoma grow more vigorously in A1 adenosine receptor (A1AR)–deficient mice associated with a strong accumulation of microglial cells at and around the tumors. A1ARs were prominently expressed in microglia associated with tumor cells as revealed with immunocytochemistry but low in microglia in the unaffected brain tissue. The A1AR could also be detected on microglia from human glioblastoma resections. To study functional interactions between tumor and host cells, we studied glioblastoma growth in organotypical brain slice cultures. A1AR agonists suppressed tumor growth. When, however, microglial cells were depleted from the slices, the agonists even stimulated tumor growth. Thus, adenosine attenuates glioblastoma growth acting via A1AR in microglia. (Cancer Res 2006; 66(17): 8550-7)
Data from MCT-1 Protein Interacts with the Cap Complex and Modulates Messenger RNA Translational Profiles
Authors: Reinert Line S. , Shi Bo , Nandi Suvobroto , Mazan-Mamczarz Krystyna , Vitolo Michele , Bachman Kurtis E. , He Huili , Gartenhaus Ronald B.
Published: March 2023

Abstract
MCT-1 is an oncogene that was initially identified in a human T cell lymphoma and has been shown to induce cell proliferation as well as activate survival-related pathways. MCT-1 contains the PUA domain, a recently described RNA-binding domain that is found in several tRNA and rRNA modification enzymes. Here, we established that MCT-1 protein interacts with the cap complex through its PUA domain and recruits the density-regulated protein (DENR/DRP), containing the SUI1 translation initiation domain. Through the use of microarray analysis on polysome-associated mRNAs, we showed that up-regulation of MCT-1 was able to modulate the translation profiles of BCL2L2, TFDP1, MRE11A, cyclin D1, and E2F1 mRNAs, despite equivalent levels of mRNAs in the cytoplasm. Our data establish a role for MCT-1 in translational regulation, and support a linkage between translational control and oncogenesis. (Cancer Res 2006; 66(18): 8994-9001)
Data from Hydrogen Peroxide Produced by Angiopoietin-1 Mediates Angiogenesis
Authors: Kim Young Mee , Kim Kyung Eun , Koh Gou Young , Ho Ye-Shih , Lee Kong-Joo
Published: March 2023

Abstract
Angiopoietin-1 (Ang1) mediates angiogenesis by enhancing endothelial cell survival and migration. It is also known that Ang1 activates Tie2, an endothelial-specific tyrosine kinase receptor, but the molecular mechanism of this process is not clear. In this study, we investigated whether reactive oxygen species (ROS) production plays a role in Ang1-mediated angiogenesis. We found that human umbilical vein endothelial cells treated with Ang1 produce ROS transiently, which was suppressed by NADPH oxidase inhibitor, diphenylene-iodonium chloride, and rotenone. The Ang1-induced ROS was identified as hydrogen peroxide (H2O2) using adenovirus-catalase infection. Removal of H2O2 by adenovirus-catalase significantly suppressed Ang1-induced in vitro endothelial cell migration, in vivo tubule formation and angiogenesis, and activation of p44/42 mitogen-activated protein kinase (MAPK), involved in cell migration, and delayed the deactivation of Akt phosphorylation involved in cell survival. Supporting to in vitro data, Ang1-induced vascular remodeling in catalase (−/−) mice was more prominent than in catalase (+/+) mice: Ang1-induced increases of the diameter of terminal arterioles and the postcapillary venules in catalase (−/−) mice were significant compared with catalase (+/+) mice. These results show that Ang1-induced H2O2 plays an important role in Ang1-mediated angiogenesis by modulating p44/42 MAPK activity. (Cancer Res 2006; 66(12): 6167-74)
Data from Echinomycin, a Small-Molecule Inhibitor of Hypoxia-Inducible Factor-1 DNA-Binding Activity
Authors: Kong Dehe , Park Eun Jung , Stephen Andrew G. , Calvani Maura , Cardellina John H. , Monks Anne , Fisher Robert J. , Shoemaker Robert H. , Melillo Giovanni
Published: March 2023

Abstract
The identification of small molecules that inhibit the sequence-specific binding of transcription factors to DNA is an attractive approach for regulation of gene expression. Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that controls genes involved in glycolysis, angiogenesis, migration, and invasion, all of which are important for tumor progression and metastasis. To identify inhibitors of HIF-1 DNA-binding activity, we expressed truncated HIF-1α and HIF-1β proteins containing the basic-helix-loop-helix and PAS domains. Expressed recombinant HIF-1α and HIF-1β proteins induced a specific DNA-binding activity to a double-stranded oligonucleotide containing a canonical hypoxia-responsive element (HRE). One hundred twenty-eight compounds previously identified in a HIF-1–targeted cell-based high-throughput screen of the National Cancer Institute 140,000 small-molecule library were tested in a 96-well plate ELISA for inhibition of HIF-1 DNA-binding activity. One of the most potent compounds identified, echinomycin (NSC-13502), a small-molecule known to bind DNA in a sequence-specific fashion, was further investigated. Electrophoretic mobility shift assay experiments showed that NSC-13502 inhibited binding of HIF-1α and HIF-1β proteins to a HRE sequence but not binding of the corresponding proteins to activator protein-1 (AP-1) or nuclear factor-κB (NF-κB) consensus sequences. Interestingly, chromatin immunoprecipitation experiments showed that NSC-13502 specifically inhibited binding of HIF-1 to the HRE sequence contained in the vascular endothelial growth factor (VEGF) promoter but not binding of AP-1 or NF-κB to promoter regions of corresponding target genes. Accordingly, NSC-13502 inhibited hypoxic induction of luciferase in U251-HRE cells and VEGF mRNA expression in U251 cells. Our results indicate that it is possible to identify small molecules that inhibit HIF-1 DNA binding to endogenous promoters.
Data from Bone Sialoprotein Mediates the Tumor Cell–Targeted Prometastatic Activity of Transforming Growth Factor β in a Mouse Model of Breast Cancer
Authors: Nam Jeong-Seok , Suchar Adam M. , Kang Mi-Jin , Stuelten Christina H. , Tang Binwu , Michalowska Aleksandra M. , Fisher Larry W. , Fedarko Neal S. , Jain Alka , Pinkas Jan , Lonning Scott , Wakefield Lalage M.
Published: March 2023

Abstract
Transforming growth factor βs (TGF-β) play a dual role in carcinogenesis, functioning as tumor suppressors early in the process, and then switching to act as prometastatic factors in late-stage disease. We have previously shown that high molecular weight TGF-β antagonists can suppress metastasis without the predicted toxicities. To address the underlying mechanisms, we have used the 4T1 syngeneic mouse model of metastatic breast cancer. Treatment of mice with a monoclonal anti-TGF-β antibody (1D11) significantly suppressed metastasis of 4T1 cells to the lungs. When metastatic 4T1 cells were recovered from lungs of 1D11-treated and control mice, the most differentially expressed gene was found to be bone sialoprotein (Bsp). Immunostaining confirmed the loss of Bsp protein in 1D11-treated lung metastases, and TGF-β was shown to regulate and correlate with Bsp expression in vitro. Functionally, knockdown of Bsp in 4T1 cells reduced the ability of TGF-β to induce local collagen degradation and invasion in vitro, and treatment with recombinant Bsp protected 4T1 cells from complement-mediated lysis. Finally, suppression of Bsp in 4T1 cells reduced metastasis in vivo. We conclude that Bsp is a plausible mediator of at least some of the tumor cell–targeted prometastatic activity of TGF-β in this model and that Bsp expression in metastases can be successfully suppressed by systemic treatment with anti-TGF-β antibodies. (Cancer Res 2006; 66(12): 6327-35)
Data from Targeted Deletion of MKK4 in Cancer Cells: A Detrimental Phenotype Manifests as Decreased Experimental Metastasis and Suggests a Counterweight to the Evolution of Tumor-Suppressor Loss
Authors: Cunningham Steven C. , Gallmeier Eike , Hucl Tomas , Dezentje David A. , Calhoun Eric S. , Falco Geppino , Abdelmohsen Kotb , Gorospe Myriam , Kern Scott E.
Published: March 2023

Abstract
Tumor-suppressors have commanded attention due to the selection for their inactivating mutations in human tumors. However, relatively little is understood about the inverse, namely, that tumors do not select for a large proportion of seemingly favorable mutations in tumor-suppressor genes. This could be explained by a detrimental phenotype accruing in a cell type–specific manner to most cells experiencing a biallelic loss. For example, MKK4, a tumor suppressor gene distinguished by a remarkably consistent mutational rate across diverse tumor types and an unusually high rate of loss of heterozygosity, has the surprisingly low rate of genetic inactivation of only ∼5%. To explore this incongruity, we engineered a somatic gene knockout of MKK4 in human cancer cells. Although the null cells resembled the wild-type cells regarding in vitro viability and proliferation in plastic dishes, there was a marked difference in a more relevant in vivo model of experimental metastasis and tumorigenesis. MKK4−/− clones injected i.v. produced fewer lung metastases than syngeneic MKK4-competent cells (P = 0.0034). These findings show how cell type-specific detrimental phenotypes can offer a paradoxical and yet key counterweight to the selective advantage attained by cells as they experiment with genetic null states during tumorigenesis, the resultant balance then determining the observed biallelic mutation rate for a given tumor-suppressor gene. (Cancer Res 2006; 66(11): 5560-4)
Data from Suppression of Melanotroph Carcinogenesis Leads to Accelerated Progression of Pituitary Anterior Lobe Tumors and Medullary Thyroid Carcinomas in Rb+/− Mice
Authors: Zhou Zongxiang , Flesken-Nikitin Andrea , Levine Corinna G. , Shmidt Elena N. , Eng Jessica P. , Nikitina Ekaterina Yu. , Spencer David M. , Nikitin Alexander Yu.
Published: March 2023

Abstract
Mice with a single copy of the retinoblastoma gene (Rb+/−) develop a syndrome of multiple neuroendocrine neoplasia. They usually succumb to fast-growing, Rb-deficient melanotroph tumors of the pituitary intermediate lobe, which are extremely rare in humans. Thus, full assessment of Rb role in other, more relevant to human pathology, neoplasms is complicated. To prevent melanotroph neoplasia while preserving spontaneous carcinogenesis in other types of cells, we have prepared transgenic mice in which 770-bp fragment of pro-opiomelanocortin promoter directs expression of the human RB gene to melanotrophs (TgPOMC-RB). In three independent lines, transgenic mice crossed to Rb+/− background are devoid of melanotroph tumors but develop the usual spectrum of other neoplasms. Interestingly, abrogation of melanotroph carcinogenesis results in accelerated progression of pituitary anterior lobe tumors and medullary thyroid carcinomas. A combination of immunologic tests, cell culture studies, and tumorigenicity assays indicates that α-melanocyte–stimulating hormone, which is overproduced by melanotroph tumors, attenuates neoplastic progression by decreasing cell proliferation and inducing apoptosis. Taken together, we show that cell lineage–specific complementation of Rb function can be successfully used for refining available models of stochastic carcinogenesis and identify α-melanocyte–stimulating hormone as a potential attenuating factor during progression of neuroendocrine neoplasms.
Data from Visualizing Chromosomes as Transcriptome Correlation Maps: Evidence of Chromosomal Domains Containing Co-expressed Genes—A Study of 130 Invasive Ductal Breast Carcinomas
Authors: Reyal Fabien , Stransky Nicolas , Bernard-Pierrot Isabelle , Vincent-Salomon Anne , de Rycke Yann , Elvin Paul , Cassidy Andrew , Graham Alexander , Spraggon Carolyn , Désille Yoann , Fourquet Alain , Nos Claude , Pouillart Pierre , Magdelénat Henri , Stoppa-Lyonnet Dominique , Couturier Jérôme , Sigal-Zafrani Brigitte , Asselain Bernard , Sastre-Garau Xavier , Delattre Olivier , Thiery Jean Paul , Radvanyi François
Published: March 2023

Abstract
Completion of the working draft of the human genome has made it possible to analyze the expression of genes according to their position on the chromosomes. Here, we used a transcriptome data analysis approach involving for each gene the calculation of the correlation between its expression profile and those of its neighbors. We used the U133 Affymetrix transcriptome data set for a series of 130 invasive ductal breast carcinomas to construct chromosomal maps of gene expression correlation (transcriptome correlation map). This highlighted nonrandom clusters of genes along the genome with correlated expression in tumors. Some of the gene clusters identified by this method probably arose because of genetic alterations, as most of the chromosomes with the highest percentage of correlated genes (1q, 8p, 8q, 16p, 16q, 17q, and 20q) were also the most frequent sites of genomic alterations in breast cancer. Our analysis showed that several known breast tumor amplicons (at 8p11-p12, 11q13, and 17q12) are located within clusters of genes with correlated expression. Using hierarchical clustering on samples and a Treeview representation of whole chromosome arms, we observed a higher-order organization of correlated genes, sometimes involving very large chromosomal domains that could extend to a whole chromosome arm. Transcription correlation maps are a new way of visualizing transcriptome data. They will help to identify new genes involved in tumor progression and new mechanisms of gene regulation in tumors.
Data from Degradation of Tob1 Mediated by SCFSkp2-Dependent Ubiquitination
Authors: Hiramatsu Yoshihiro , Kitagawa Kyoko , Suzuki Toru , Uchida Chiharu , Hattori Takayuki , Kikuchi Hirotoshi , Oda Toshiaki , Hatakeyama Shigetsugu , Nakayama Keiichi I. , Yamamoto Tadashi , Konno Hiroyuki , Kitagawa Masatoshi
Published: March 2023

Abstract
Tob1, a member of the Tob/BTG family, is involved in the control of G1-S progression by suppressing cyclin D1 expression and acts as a tumor suppressor gene. Tob1 was reported to have a quick turnover through the ubiquitin-proteasome pathway, but proteins involved in this process are still unknown. We showed that Skp2, a substrate-targeting subunit of the SCF (Skp1/Cul1/F-box protein) ubiquitin ligase complex, was involved in ubiquitin-dependent degradation of Tob1. Skp2 interacted with Tob1 and facilitated ubiquitination of Tob1 in intact cells as well as in vitro. Skp2 mutants without the F-box or leucine rich repeat were not able to bind to Tob1 and did not enhance ubiquitination of Tob1. Tob1 was stabilized in both Skp2−/− mouse fibroblasts and Skp2 knockdown HeLa cells. Moreover, cyclin D1 expression was suppressed in Skp2 knockdown HeLa cells. These data suggest that Tob1 is a novel target for degradation by the SCF-Skp2 ubiquitin ligase. (Cancer Res 2006; 66(17): 8477-83)
Data from Hypermethylation of ASC/TMS1 Is a Sputum Marker for Late-Stage Lung Cancer
Authors: Machida Emi Ota , Brock Malcolm V. , Hooker Craig M. , Nakayama Jun , Ishida Akiko , Amano Jun , Picchi Maria A. , Belinsky Steven A. , Herman James G. , Taniguchi Shun'ichiro , Baylin Stephen B.
Published: March 2023

Abstract
DNA hypermethylated gene promoter sequences are extremely promising cancer markers. Their use for risk assessment, early diagnosis, or prognosis depends on the timing of this gene change during tumor progression. We studied this for the proapoptotic gene ASC/TMS1 in lung cancer and used the findings to develop a sputum marker. ASC/TMS1 protein levels are reduced in all lung cancer types (30 of 40; 75%) but not in 10 preinvasive lesions. Hypermethylation of ASC/TMS1 is also associated with invasive cancers (41 of 152 or 27.0% of all lung cancer types) with variation in incidence between histopathologic types including 32.1% (26 of 81) of adenocarcinomas, 13.2% (7 of 53) of squamous cell carcinomas, 38.5% (5 of 13) of large-cell carcinomas, and 60% (3 of 5) of small-cell lung cancers. The hypermethylation is particularly correlated with late tumor stages being present in only 14% of stage I but 60% of later-stage tumors. The incidence of ASC/TMS1 hypermethylation in sputum DNA fully mimics the tissue findings being present in only 2% (2 of 85) of high-risk, cancer-free smokers, 15% (3 of 18) of patients with stage I non–small-cell lung cancer (NSCLC), but 41% of patients with stage III NSCLC (18 of 44), including 56% (10 of 18) of those with adenocarcinoma. Importantly, sputum is positive for this marker in 24% (10 of 42) of very high risk, clinically cancer-free individuals previously resected for stage I NSCLC. Thus, hypermethylation of ASC/TMS1 is a marker for late-stage lung cancer and, in sputum, could predict prognosis in patients resected for early-stage disease. (Cancer Res 2006; 66(12): 6210-8)
Data from Transforming Growth Factor-β Promotes Invasion in Tumorigenic but not in Nontumorigenic Human Prostatic Epithelial Cells
Authors: Ao Mingfang , Williams Karin , Bhowmick Neil A. , Hayward Simon W.
Published: March 2023

Abstract
Transforming growth factor-β (TGF-β) is a pleiotropic growth factor with actions that are dependent on circumstances, including dose, target cell type, and context. TGF-β can elicit both growth-promoting and growth-suppressive activities. In normal tissues, TGF-β generally acts to restrict growth and maintain differentiation. However, during tumorigenesis, changes in TGF-β expression and cellular responses can promote tumorigenesis. The present study examines the effects of TGF-β on the nontumorigenic human prostatic epithelial cell line BPH1 and on three derivative tumorigenic sublines BPH1CAFTD1, BPH1CAFTD3, and BPH1CAFTD5. The data show that TGF-β has different effects on the nontumorigenic and tumorigenic cells. The nontumorigenic cells are growth inhibited by TGF-β. In contrast, the tumorigenic sublines are not growth inhibited but instead undergo an epithelial to mesenchymal transformation (EMT) in response to TGF-β. The tumorigenic lines show constitutively elevated levels of phosphorylated Akt, which modulates their response to TGF-β by blocking Smad3 and p21 nuclear translocation. On TGF-β stimulation of the tumorigenic sublines, the activated Akt allows the cell to escape cell cycle arrest. The phosphatidylinositol 3-kinase/Akt pathway is also involved in TGF-β-induced EMT, defined here by induction of vimentin expression and enhanced cellular motility. In vivo, tumorigenic cells with constitutively active TGF-β signaling show increased invasion with EMT, which express vimentin, located specifically at the invasive front of the tumor. These data indicate that following malignant transformation TGF-β can play a direct role in promoting prostatic cancer and further that these responses are context specific in vivo. (Cancer Res 2006; 66(16): 8007-16)
Data from Breast Cancer Cells Stimulate Neutrophils to Produce Oncostatin M: Potential Implications for Tumor Progression
Authors: Queen Marisa M. , Ryan Randall E. , Holzer Ryan G. , Keller-Peck Cynthia R. , Jorcyk Cheryl L.
Published: March 2023

Abstract
Tumor-associated and tumor-infiltrating neutrophils (TAN) and macrophages (TAM) can account for as much as 50% of the total tumor mass in invasive breast carcinomas. It is thought that tumors secrete factors that elicit a wound-repair response from TAMs and TANs and that this response inadvertently stimulates tumor progression. Oncostatin M is a pleiotropic cytokine belonging to the interleukin-6 family that is expressed by several cell types including activated human T lymphocytes, macrophages, and neutrophils. Whereas oncostatin M can inhibit the proliferation of breast cancer cells in vitro, recent studies suggest that oncostatin M may promote tumor progression by enhancing angiogenesis and metastasis. In addition, neutrophils can be stimulated to synthesize and rapidly release large quantities of oncostatin M. In this article, we show that human neutrophils secrete oncostatin M when cocultured with MDA-MB-231 and T47D human breast cancer cells. Neutrophils isolated from whole blood or breast cancer cells alone express little oncostatin M by immunocytochemistry and ELISA, but neutrophils express and release high levels of oncostatin M when they are cocultured with breast cancer cells. In addition, we show that granulocyte-macrophage colony-stimulating factor produced by breast cancer cells and cell-cell contact are both necessary for the release of oncostatin M from neutrophils. Importantly, neutrophil-derived oncostatin M induces vascular endothelial growth factor from breast cancer cells in coculture and increases breast cancer cell detachment and invasive capacity, suggesting that neutrophils and oncostatin M may promote tumor progression in vivo.
Data from CpG Island Methylator Phenotype Is a Strong Determinant of Poor Prognosis in Neuroblastomas
Authors: Abe Masanobu , Ohira Miki , Kaneda Atsushi , Yagi Yukiko , Yamamoto Seiichiro , Kitano Yoshihiro , Takato Tsuyoshi , Nakagawara Akira , Ushijima Toshikazu
Published: March 2023

Abstract
Neuroblastoma, one of the most common pediatric solid tumors, is characterized by two extreme disease courses, spontaneous regression and life-threatening progression. Here, we conducted a genome-wide search for differences in DNA methylation that distinguish between neuroblastomas of the two types. Three CpG islands (CGI) and two groups of CGIs were found to be methylated specifically in neuroblastomas with a poor prognosis. By quantitative analysis of 140 independent cases, methylation of all the five CGI (groups) was shown to be closely associated with each other, conforming to the CpG island methylator phenotype (CIMP) concept. The presence of CIMP was sensitively detected by methylation of the PCDHB CGIs and associated with significantly poor survival (hazard ratio, 22.1; 95% confidence interval, 5.3-93.4; P < 0.0001). Almost all cases with N-myc amplification (37 of 38 cases) exhibited CIMP. Even in 102 cases without N-myc amplification, the presence of CIMP (30 cases) strongly predicted poor survival (hazard ratio, 12.4; 95% confidence interval, 2.6-58.9; P = 0.002). Methylation of PCDHB CGIs, located in their gene bodies, did not suppress gene expression or induce histone modifications. However, CIMP was significantly associated with methylation of promoter CGIs of the RASSF1A and BLU tumor suppressor genes. The results showed that neuroblastomas with CIMP have a poor prognosis and suggested induction of silencing of important genes as an underlying mechanism.
Data from Common Genetic Variants in Proinflammatory and Other Immunoregulatory Genes and Risk for Non-Hodgkin Lymphoma
Authors: Wang Sophia S. , Cerhan James R. , Hartge Patricia , Davis Scott , Cozen Wendy , Severson Richard K. , Chatterjee Nilanjan , Yeager Meredith , Chanock Stephen J. , Rothman Nathaniel
Published: March 2023

Abstract
Profound disruption of immune function is an established risk factor for non-Hodgkin lymphoma. We report here a large-scale evaluation of common genetic variants in immune genes and their role in lymphoma. We genotyped 57 single nucleotide polymorphisms (SNP) from 36 candidate immune genes in 1,172 non-Hodgkin lymphoma cases and 982 population-based controls from a US multicenter study. We calculated odds ratios (OR) and 95% confidence intervals (95% CI) for the association between individual SNP and haplotypes with non-Hodgkin lymphoma overall and five well-defined subtypes. A haplotype comprising SNPs in two proinflammatory cytokines, tumor necrosis factor-α and lymphotoxin-α (rs1800629, rs361525, rs1799724, rs909253, and rs2239704), increased non-Hodgkin lymphoma risk overall (OR, 1.31; 95% CI, 1.06-1.63; P = 0.01) and notably for diffuse large B cell (OR, 1.64; 95% CI, 1.23-2.19; P = 0.0007). A functional nonsynonymous SNP in the innate immune gene Fcγ receptor 2A (FCGR2A; rs1801274) was also associated with non-Hodgkin lymphoma; AG and AA genotypes were associated with a 1.26-fold (95% CI, 1.01-1.56) and 1.41-fold (95% CI, 1.10-1.81) increased risk, respectively (Ptrend = 0.006). Among non-Hodgkin lymphoma subtypes, the association with FCGR2A was pronounced for follicular and small lymphocytic lymphomas. In conclusion, common variants in genes influencing proinflammatory and innate immune responses were associated with non-Hodgkin lymphoma risk overall and their effects could vary by subtype. Our results require replication but potentially provide important clues for investigating common genetic variants as susceptibility factors and in disease outcomes, treatment responses, and immunotherapy targets. (Cancer Res 2006; 66(19): 9771-80)
Data from Caspase-8 Promotes Cell Motility and Calpain Activity under Nonapoptotic Conditions
Authors: Helfer Brooke , Boswell Bernard C. , Finlay Darren , Cipres Angel , Vuori Kristiina , Bong Kang Tae , Wallach David , Dorfleutner Andrea , Lahti Jill M. , Flynn Daniel C. , Frisch Steven M.
Published: March 2023

Abstract
Significant caspase-8 activity has been found in normal and certain tumor cells, suggesting that caspase-8 possesses an alternative, nonapoptotic function that may contribute to tumor progression. In this article, we report that caspase-8 promotes cell motility. In particular, caspase-8 is required for the optimal activation of calpains, Rac, and lamellipodial assembly. This represents a novel nonapoptotic function of caspase-8 acting at the intersection of the caspase-8 and calpain proteolytic pathways to coordinate cell death versus cell motility signaling. (Cancer Res 2006; 66(8): 4273-8)
Data from Systemic Targeting Inhibitor of κB Kinase Inhibits Melanoma Tumor Growth
Authors: Yang Jinming , Pan Wei-Hua , Clawson Gary A. , Richmond Ann
Published: March 2023

Abstract
Constitutive activation of nuclear factor-κB (NF-κB) has been directly implicated in tumorigenesis of various cancer types, including melanoma. Inhibitor of κB kinase (IKK) functions as a major mediator of NF-κB activation. Thus, development of an IKK-specific inhibitor has been a high priority, although it remains unclear whether systemic inhibition of IKK will provide therapeutic benefit. In this study, we show that inhibition of NF-κB activity in melanocytes that are persistently expressing an active H-RasV12 gene and are deficient in the tumor suppressors inhibitor A of cyclin-dependent kinase 4/alternative reading frame results in reduction of melanoma tumor growth in vivo. This effect is, at least in part, via regulation of NF-κB nuclear activation and RelA phosphorylation. Based on this result, we developed a double hammerhead ribozyme long-term expression system to silence either IKKα or IKKβ. The ribozymes were placed in an EBV construct and delivered i.v. to nude mice bearing melanoma lesions, which developed after i.v. injection of H-Ras–transformed melanoma cells. Our in vivo data show that knockdown of endogenous IKKβ significantly reduces the growth of the melanoma lesions and knockdown of either IKKα or IKKβ prolongs the life span of immunocompetent mice. [Cancer Res 2007;67(7):3127–34]
Data from Multiple Robust Signatures for Detecting Lymph Node Metastasis in Head and Neck Cancer
Authors: Roepman Paul , Kemmeren Patrick , Wessels Lodewijk F.A. , Slootweg Piet J. , Holstege Frank C.P.
Published: March 2023

Abstract
Genome-wide mRNA expression measurements can identify molecular signatures of cancer and are anticipated to improve patient management. Such expression profiles are currently being critically evaluated based on an apparent instability in gene composition and the limited overlap between signatures from different studies. We have recently identified a primary tumor signature for detection of lymph node metastasis in head and neck squamous cell carcinomas. Before starting a large multicenter prospective validation, we have thoroughly evaluated the composition of this signature. A multiple training approach was used for validating the original set of predictive genes. Based on different combinations of training samples, multiple signatures were assessed for predictive accuracy and gene composition. The initial set of predictive genes is a subset of a larger group of 825 genes with predictive power. Many of the predictive genes are interchangeable because of a similar expression pattern across the tumor samples. The head and neck metastasis signature has a more stable gene composition than previous predictors. Exclusion of the strongest predictive genes could be compensated by raising the number of genes included in the signature. Multiple accurate predictive signatures can be designed using various subsets of predictive genes. The absence of genes with strong predictive power can be compensated by including more genes with lower predictive power. Lack of overlap between predictive signatures from different studies with the same goal may be explained by the fact that there are more predictive genes than required to design an accurate predictor. (Cancer Res 2006; 66(4): 2361-6)