bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Comparative Analysis of Normal versus CLL B-Lymphocytes Reveals Patient-Specific Variability in Signaling Mechanisms Controlling LFA-1 Activation by Chemokines
Authors: Montresor Alessio , Bolomini-Vittori Matteo , Simon Scott I. , Rigo Antonella , Vinante Fabrizio , Laudanna Carlo
Published: March 2023

Abstract
Activation of lymphocyte function–associated antigen-1 (LFA-1) by chemokines is fine-tuned by inside-out signaling mechanisms responsible for integrin-mediated adhesion modulation. In the present study, we investigated the possibility of qualitative variability of signaling mechanisms controlling LFA-1 activation in chronic lymphocytic leukemia (CLL) cells. We pursued a multiplexed comparative analysis of the role of the recently described chemokine-triggered rho-signaling module in human normal versus CLL B-lymphocytes. We found that the rho-module of LFA-1 affinity triggering is functionally conserved in normal B-lymphocytes. In contrast, in malignant B-lymphocytes isolated from patients with B-CLL, the role of the rho-module was not maintained, showing remarkable differences and variability. Specifically, RhoA and phospholipase D1 were crucially involved in LFA-1 affinity triggering by CXCL12 in all analyzed patients. In contrast, Rac1 and CDC42 involvement displayed a consistent patient-by-patient variability, with a group of patients showing LFA-1 affinity modulation totally independent of Rac1 and CDC42 signaling activity. Finally, phosphatidylinositol-4-phosphate 5-kinase isoform 1γ (PIP5KC) was found without any regulatory role in all patients. The data imply that the neoplastic progression may completely bypass the regulatory role of Rac1, CDC42, and PIP5KC, and show a profound divergence in the signaling mechanisms controlling integrin activation in normal versus neoplastic lymphocytes, suggesting that patients with CLL can be more accurately evaluated on the basis of the analysis of signaling mechanisms controlling integrin activation. Our findings could potentially affect the diagnosis, prognosis, and therapy of CLL disorders. [Cancer Res 2009;69(24):9281–90]
Data from MiR-15a and MiR-16 Control Bmi-1 Expression in Ovarian Cancer
Authors: Bhattacharya Resham , Nicoloso Milena , Arvizo Rochelle , Wang Enfeng , Cortez Angelica , Rossi Simona , Calin George A. , Mukherjee Priyabrata
Published: March 2023

Abstract
Oncogenic activation of Bmi-1 is found in a wide variety of epithelial malignancies including ovarian cancer, yet a specific mechanism for overexpression of Bmi-1 has not been determined. Thus, realizing the immense pathologic significance of Bmi-1 in cancer, we wanted to investigate if microRNA (miRNA) aberrations played a role in the regulation of Bmi-1 in ovarian cancer. In this report, we identify two miRNAs, miR-15a and miR-16, that are underexpressed in ovarian cell lines and in primary ovarian tissues. We show that these miRNAs directly target the Bmi-1 3′ untranslated region and significantly correlate with Bmi-1 protein levels in ovarian cancer patients and cell lines. Furthermore, Bmi-1 protein levels are downregulated in response to miR-15a or miR-16 expression and lead to significant reduction in ovarian cancer cell proliferation and clonal growth. These findings suggest the development of therapeutic strategies by restoring miR-15a and miR-16 expression in ovarian cancer and in other cancers that involve upregulation of Bmi-1. [Cancer Res 2009;69(23):9090–5]
Data from Akt3-Mediated Resistance to Apoptosis in B-RAF–Targeted Melanoma Cells
Authors: Shao Yongping , Aplin Andrew E.
Published: March 2023

Abstract
Melanoma cells are highly resistant to anoikis, a form of apoptosis induced in nonadherent/inappropriate adhesion conditions. Depleting B-RAF or the prosurvival Bcl-2 family protein Mcl-1 renders mutant B-RAF melanoma cells susceptible to anoikis. In this study, we examined the effect of targeting B-RAF on the survival of primary stage melanoma cells cultured in three-dimensional type I collagen gels, which partially mimics the dermal microenvironment. Depletion/inhibition of B-RAF with small interfering RNA or the mutant B-RAF inhibitor, PLX4720, induced apoptosis of mutant B-RAF melanoma cells in three-dimensional collagen. Apoptosis was dependent on two upregulated BH3-only proteins, Bim-EL and Bmf, and was inhibited by ectopic Mcl-1 expression. Akt3 activation has been associated with the survival of melanoma cells. Mutant B-RAF melanoma cells ectopically expressing a constitutively activated form of Akt3 or endogenously expressing mutant Akt3 were protected from apoptosis induced by B-RAF knockdown or PLX4720 treatment. Furthermore, intrinsically resistant metastatic melanoma cells displayed elevated Akt phosphorylation in three-dimensional collagen and were rendered susceptible to PLX4720 by Akt3 knockdown. Importantly, myristylated Akt3 prevented B-RAF targeting–induced upregulation of Bim-EL and Bmf in three-dimensional collagen and partially protected Mcl-1–depleted cells from apoptosis. These findings delineate how mutant B-RAF protects melanoma cells from apoptosis and provide insight into possible resistance mechanisms to B-RAF inhibitors. Cancer Res; 70(16); 6670–81. ©2010 AACR.
Data from A Novel Imaging Approach for Early Detection of Prostate Cancer Based on Endogenous Zinc Sensing
Authors: Ghosh Subrata K. , Kim Pilhan , Zhang Xiao-an , Yun Seok-Hyun , Moore Anna , Lippard Stephen J. , Medarova Zdravka
Published: March 2023

Abstract
The early detection of prostate cancer is a life-saving event in patients harboring potentially aggressive disease. With the development of malignancy, there is a dramatic reduction in the zinc content of prostate tissue associated with the inability of cancer cells to accumulate the ion. In the current study, we used endogenous zinc as an imaging biomarker for prostate cancer detection and progression monitoring. We employed a novel fluorescent sensor for mobile zinc (ZPP1) to detect and monitor the development of prostate cancer in a transgenic mouse model of prostate adenocarcinoma, using in vivo optical imaging correlated with biological fluid-based methods. We showed that the progression of prostate cancer could be monitored in vivo judging by the decreasing zinc content in the prostates of tumor-bearing mice in an age-dependent manner. In a novel quantitative assay, we determined the concentration of mobile zinc in both prostate cell lysates and mouse prostate extracts through simple titration of the ZPP1 sensor. Our findings fulfill the promise of zinc-based prostate cancer diagnostics with the prospect for immediate clinical translation. Cancer Res; 70(15); 6119–27. ©2010 AACR.
Data from Immunologic Consequences of Signal Transducers and Activators of Transcription 3 Activation in Human Squamous Cell Carcinoma
Authors: Albesiano Emilia , Davis Meghan , See Alfred P. , Han James E. , Lim Michael , Pardoll Drew M. , Kim Young
Published: March 2023

Abstract
Paracrine cross-talk between tumor cells and immune cells within the tumor microenvironment underlies local mechanisms of immune evasion. Signal transducer and activator of transcription 3 (STAT3), which is constitutively activated in diverse cancer types, is a key regulator of cytokine and chemokine expression in murine tumors, resulting in suppression of both innate and adaptive antitumor immunity. However, the immunologic effects of STAT3 activation in human cancers have not been studied in detail. To investigate how STAT3 activity in human head and neck squamous cell carcinoma (HNSCC) might alter the tumor microenvironment to enable immune escape, we used small interfering RNA and small-molecule inhibitors to suppress STAT3 activity. STAT3 inhibition in multiple primary and established human squamous carcinoma lines resulted in enhanced expression and secretion of both proinflammatory cytokines and chemokines. Although conditioned medium containing supernatants from human HNSCC inhibited lipopolysaccharide-induced dendritic cell activation in vitro, supernatants from STAT3-silenced tumor cells reversed this immune evasion mechanism. Moreover, supernatants from STAT3-silenced tumor cells were able to stimulate the migratory behavior of lymphocytes from human peripheral blood in vitro. These results show the importance of STAT3 activation in regulating the immunomodulatory mediators by human tumors and further validate STAT3 as a promising target for therapeutic intervention. Cancer Res; 70(16); 6467–76. ©2010 AACR.
Data from Host Lymphodepletion Enhances the Therapeutic Activity of an Oncolytic Vaccinia Virus Expressing 4-1BB Ligand
Authors: Kim Hong Sung , Kim-Schulze Seunghee , Kim Dae Won , Kaufman Howard L.
Published: March 2023

Abstract
Oncolytic viral vectors have shown promise as antitumor therapeutic agents but their effectiveness is complicated by induction of antiviral antibody responses and rapid host clearance of recombinant vectors. We developed a recombinant oncolytic vaccinia virus expressing the 4-1BBL T-cell costimulatory molecule (rV-4-1BBL) and showed modest tumor regression in the poorly immunogenic B16 murine melanoma model. To improve the therapeutic potential of this vector, we tested the antitumor activity of local intratumoral injection in the setting of host lymphodepletion, which has been shown to augment vaccination and adoptive T-cell therapy. In this model, rV-4-1BBL injection in the setting of lymphodepletion promoted MHC class I expression, reduced antiviral antibody titers, promoted viral persistence, and rescued effector-memory CD8+ T cells, significantly improving the therapeutic effectiveness of the oncolytic vector. These data suggest that vaccination with rV-4-1BBL in the setting of host nonmyeloablative lymphodepletion represents a logical strategy for improving oncolytic vaccination in melanoma, and perhaps other cancers as well. [Cancer Res 2009;69(21):8516–25]
Data from Overactivation of the MEK/ERK Pathway in Liver Tumor Cells Confers Resistance to TGF-β–Induced Cell Death through Impairing Up-regulation of the NADPH Oxidase NOX4
Authors: Caja Laia , Sancho Patricia , Bertran Esther , Iglesias-Serret Daniel , Gil Joan , Fabregat Isabel
Published: March 2023

Abstract
Transforming growth factor-β (TGF-β) induces apoptosis in hepatocytes, being considered a liver tumor suppressor. However, many human hepatocellular carcinoma (HCC) cells escape from its proapoptotic effects, gaining response to this cytokine in terms of malignancy. We have recently reported that the apoptosis induced by TGF-β in hepatocytes requires up-regulation of the NADPH oxidase NOX4, which mediates reactive oxygen species (ROS) production. TGF-β–induced NOX4 expression is inhibited by antiapoptotic signals, such as the phosphatydilinositol-3-phosphate kinase or the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathways. The aim of the present work was to analyze whether resistance to TGF-β–induced apoptosis in HCC cells is related to the impairment of NOX4 up-regulation due to overactivation of survival signals. Results indicate that inhibition of the MAPK/ERK kinase (MEK)/ERK pathway in HepG2 cells, which are refractory to the proapoptotic effects of TGF-β, sensitizes them to cell death through a mitochondrial-dependent mechanism, coincident with increased levels of BIM and BMF, decreased levels of BCL-XL and MCL1, and BAX/BAK activation. Regulation of BMF, BCL-XL, and MCL1 occurs at the mRNA level, whereas BIM regulation occurs post-transcriptionally. ROS production and glutathione depletion are only observed in cells treated with TGF-β and PD98059, which correlates with NOX4 up-regulation. Targeting knockdown of NOX4 impairs ROS increase and all the mitochondrial-dependent apoptotic features by a mechanism that is upstream from the regulation of BIM, BMF, BCL-XL, and MCL1 levels. In conclusion, overactivation of the MEK/ERK pathway in liver tumor cells confers resistance to TGF-β–induced cell death through impairing NOX4 up-regulation, which is required for an efficient mitochondrial-dependent apoptosis. [Cancer Res 2009;69(19):7595–602]
Data from Cancer Prevention: From 1727 to Milestones of the Past 100 Years
Authors: Lippman Scott M. , Hawk Ernest T.
Published: March 2023

Abstract
The rich, multidisciplinary history of cancer prevention recounted here begins with surgical and workplace recommendations of the 1700s and ends with 2009 results of the enormous (35,535 men) Selenium and Vitamin E [prostate] Cancer Prevention Trial (SELECT). This history comprises a fascinating array of chemopreventive, vaccine, surgical, and behavioral science research, both preclinical and clinical. Preclinical milestones of cancer prevention include the 1913 and 1916 mouse studies by Lathrop and Loeb of cancer development associated with pregnancy or cancer prevention through castration (oophorectomy), preventing chemically induced mouse carcinogenesis as early as 1929, energy restriction studies in the 1940s, the 1950s discoveries and later molecular characterizations of field cancerization and multistep carcinogenesis, and the effects of angiogenesis inhibition in genetically engineered mice reported in 2009. The extraordinary panoply of clinical research includes numerous large and smaller chemoprevention studies of nutritional supplements, other dietary approaches, a Bacillus Calmette-Guérin trial in 1976, molecular-targeted agents, and agents to prevent infection-related cancers such as hepatitis B virus vaccine to prevent liver cancer in 1984. Clinical surgical prevention includes removal of intraepithelial neoplasia detected by screening (including Pap testing developed in 1929 and culposcopy for cervical premalignancy and colonoscopy and polypectomy to prevent colorectal cancer begun in the 1960s) and prophylactic surgeries, such as in Lynch syndrome patients begun in 1977. Behavioral studies include smoking cessation and control beginning in the 1950s, obesity control rooted in studies of 1841, and genetic-counseling and cancer-survivorship studies. This history of pioneering events may help in better understanding who we are and what we want to achieve as cancer prevention researchers and practitioners. [Cancer Res 2009;69(13):5269–84]
Data from Epigenetic Inactivation of the Potential Tumor Suppressor Gene FOXF1 in Breast Cancer
Authors: Lo Pang-Kuo , Lee Ji Shin , Liang Xiaohui , Han Liangfeng , Mori Tsuyoshi , Fackler Mary Jo , Sadik Helen , Argani Pedram , Pandita Tej K. , Sukumar Saraswati
Published: March 2023

Abstract
The expression of several members of the FOX gene family is known to be altered in a variety of cancers. We show that in breast cancer, FOXF1 gene is a target of epigenetic inactivation and that its gene product exhibits tumor-suppressive properties. Loss or downregulation of FOXF1 expression is associated with FOXF1 promoter hypermethylation in breast cancer cell lines and in invasive ductal carcinomas. Methylation of FOXF1 in invasive ductal carcinoma (37.6% of 117 cases) correlated with high tumor grade. Pharmacologic unmasking of epigenetic silencing in breast cancer cells restored FOXF1 expression. Re-expression of FOXF1 in breast cancer cells with epigenetically silenced FOXF1 genes led to G1 arrest concurrent with or without apoptosis to suppress both in vitro cell growth and in vivo tumor formation. FOXF1-induced G1 arrest resulted from a blockage at G1-S transition of the cell cycle through inhibition of the CDK2-RB-E2F cascade. Small interfering RNA–mediated depletion of FOXF1 in breast cancer cells led to increased DNA re-replication, suggesting that FOXF1 is required for maintaining the stringency of DNA replication and genomic stability. Furthermore, expression profiling of cell cycle regulatory genes showed that abrogation of FOXF1 function resulted in increased expression of E2F-induced genes involved in promoting the progression of S and G2 phases. Therefore, our studies have identified FOXF1 as a potential tumor suppressor gene that is epigenetically silenced in breast cancer, which plays an essential role in regulating cell cycle progression to maintain genomic stability. Cancer Res; 70(14); 6047–58. ©2010 AACR.
Data from Histone Methyltransferase Gene SETD2 Is a Novel Tumor Suppressor Gene in Clear Cell Renal Cell Carcinoma
Authors: Duns Gerben , van den Berg Eva , van Duivenbode Inge , Osinga Jan , Hollema Harry , Hofstra Robert M.W. , Kok Klaas
Published: March 2023

Abstract
Sporadic clear cell renal cell carcinoma (cRCC) is genetically characterized by the recurrent loss of the short arm of chromosome 3, with a hotspot for copy number loss in the 3p21 region. We applied a method called “gene identification by nonsense-mediated mRNA decay inhibition” to a panel of 10 cRCC cell lines with 3p21 copy number loss to identify biallelic inactivated genes located at 3p21. This revealed inactivation of the histone methyltransferase gene SETD2, located on 3p21.31, as a common event in cRCC cells. SETD2 is nonredundantly responsible for trimethylation of the histone mark H3K36. Consistent with this function, we observed loss or a decrease of H3K36me3 in 7 out of the 10 cRCC cell lines. Identification of missense mutations in 2 out of 10 primary cRCC tumor samples added support to the involvement of loss of SETD2 function in the development of cRCC tumors. Cancer Res; 70(11); 4287–91. ©2010 AACR.
Data from Alternatively Spliced RAGEv1 Inhibits Tumorigenesis through Suppression of JNK Signaling
Authors: Kalea Anastasia Z. , See Fiona , Harja Evis , Arriero Maria , Schmidt Ann Marie , Hudson Barry I.
Published: March 2023

Abstract
Receptor for advanced glycation end products (RAGE) and its ligands are overexpressed in multiple cancers. RAGE has been implicated in tumorigenesis and metastasis, but little is known of the mechanisms involved. In this study, we define a specific functional role for an alternate splice variant termed RAGE splice variant 1 (RAGEv1), which encodes a soluble endogenous form of the receptor that inhibits tumorigenesis. RAGEv1 was downregulated in lung, prostate, and brain tumors relative to control matched tissues. Overexpressing RAGEv1 in tumor cells altered RAGE ligand stimulation of several novel classes of genes that are critical in tumorigenesis and metastasis. Additionally, RAGEv1 inhibited tumor formation, cell invasion, and angiogenesis induced by RAGE ligand signaling. Analysis of signal transduction pathways underlying these effects revealed marked suppression of c-jun-NH2-kinase (JNK) pathway signaling, and JNK inhibition suppressed signaling through the RAGE pathway. Tumors expressing RAGEv1 were significantly smaller than wild-type tumors and displayed prominently reduced activation of JNK. Our results identify RAGEv1 as a novel suppressor, the study of which may offer new cancer therapeutic directions. Cancer Res; 70(13); 5628–38. ©2010 AACR.
Data from Cancer Stem Cells and Aneuploid Populations within Developing Tumors Are the Major Determinants of Tumor Dormancy
Authors: Kusumbe Anjali P. , Bapat Sharmila A.
Published: March 2023

Abstract
Tumor formation involves substantial cell division and genetic instability, but the relationship between quiescent cancer stem cells (CSC) and dividing progenitors in these events is poorly understood. Likewise, the implication of aneuploid cells in solid tumors is uncertain. CSCs are postulated to contribute to tumor dormancy and present a formidable obstacle in limiting treatment outcomes for a majority of cancers, whereas the genetic heterogeneity conjured by aneuploid cells may influence tumor drug resistance. However, direct confirmation of these events remains forthcoming. In the present study, we addressed the identification of tumor dormancy in terms of isolation of therapy-refractory residual tumor cells from tumors that persist in a state of quiescence as label-retaining cells. The choices of label were PKH67/PKH26 dyes that irreversibly bind to the lipid bilayer on cell membranes and get equally partitioned among daughter cells subsequent to each cell division. Consequent characterization revealed that label-retaining cells encompass two different populations capable of remaining in a state of quiescence, i.e., stem-like cells and aneuploid cells. The former express a reversibility of quiescence through retention of functionality and also exhibit therapeutic refractoriness; the latter seem to be either quiescent or proliferation-arrested at steady-state. Subsequent to exposure to selective pressure of chemotherapy, a fraction of these cells may acquire the potential to proliferate in a drug-refractory manner and acquire stem-like characteristics. Collectively, the findings of the present study reveal that tumor-derived CSCs and aneuploid populations contribute to drug resistance and tumor dormancy in cancer progression. [Cancer Res 2009;69(24):9245–53]
Data from A Proteomic Approach for the Identification of Vascular Markers of Liver Metastasis
Authors: Borgia Beatrice , Roesli Christoph , Fugmann Tim , Schliemann Christoph , Cesca Marta , Neri Dario , Giavazzi Raffaella
Published: March 2023

Abstract
Vascular proteins expressed at liver metastasis sites could serve as prognostic markers or as targets for pharmacodelivery applications. We employed a proteomic approach to define such proteins in three syngeneic mouse models of liver metastasis. Vascular structures were biotinylated in vivo by a terminal perfusion technique, followed by mass spectrometric analysis of accessible biotinylated proteins. In this manner, we identified 12 proteins for which expression was selectively associated with liver metastasis, confirming this association by tissue immunofluorescence or in vivo localization with radiolabeled antibodies. In summary, our findings identify vascular proteins that may have prognostic or drug-targeting use in addressing liver metastases, a common issue in many advanced cancers. Cancer Res; 70(1); 309–18
Data from MAP Kinase-Interacting Kinase 1 Regulates SMAD2-Dependent TGF-β Signaling Pathway in Human Glioblastoma
Authors: Grzmil Michal , Morin Pier , Lino Maria Maddalena , Merlo Adrian , Frank Stephan , Wang Yuhua , Moncayo Gerald , Hemmings Brian A.
Published: March 2023

Abstract
Glioblastoma multiforme (GBM) is the most common aggressive brain cancer with a median survival of approximately 1 year. In a search for novel molecular targets that could be therapeutically developed, our kinome-focused microarray analysis identified the MAP (mitogen-activated protein) kinase-interacting kinase 1 (MNK1) as an attractive theranostic candidate. MNK1 overexpression was confirmed in both primary GBMs and glioma cell lines. Inhibition of MNK1 activity in GBM cells by the small molecule CGP57380 suppressed eIF4E phosphorylation, proliferation, and colony formation whereas concomitant treatment with CGP57380 and the mTOR inhibitor rapamycin accentuated growth inhibition and cell-cycle arrest. siRNA-mediated knockdown of MNK1 expression reduced proliferation of cells incubated with rapamycin. Conversely, overexpression of full-length MNK1 reduced rapamycin-induced growth inhibition. Analysis of polysomal profiles revealed inhibition of translation in CGP57380 and rapamycin-treated cells. Microarray analysis of total and polysomal RNA from MNK1-depleted GBM cells identified mRNAs involved in regulation of TGF-β pathway. Translation of SMAD2 mRNA as well as TGF-β–induced cell motility and vimentin expression was regulated by MNK1 signaling. Tissue microarray analysis revealed a positive correlation between the immunohistochemical staining of MNK1 and SMAD2. Taken together, our findings offer insights into how MNK1 pathways control translation of cancer-related mRNAs including SMAD2, a key component of the TGF-β signaling pathway. Furthermore, they suggest MNK1-controlled translational pathways in targeted strategies to more effectively treat GBM. Cancer Res; 71(6); 2392–402. ©2011 AACR.
Data from Genome-Wide Analysis of Alternative Splicing in Medulloblastoma Identifies Splicing Patterns Characteristic of Normal Cerebellar Development
Authors: Menghi Francesca , Jacques Thomas S. , Barenco Martino , Schwalbe Ed C. , Clifford Steven C. , Hubank Mike , Ham Jonathan
Published: March 2023

Abstract
Alternative splicing is an important mechanism for the generation of protein diversity at a post‐transcriptional level. Modifications in the splicing patterns of several genes have been shown to contribute to the malignant transformation of different tissue types. In this study, we used the Affymetrix Exon arrays to investigate patterns of differential splicing between pediatric medulloblastomas and normal cerebellum on a genome-wide scale. Of the 1,262 genes identified as potentially generating tumor-associated splice forms, we selected 14 examples of differential splicing of known cassette exons and successfully validated 11 of them by reverse transcriptase PCR. The pattern of differential splicing of three validated events was characteristic for the molecular subset of sonic hedgehog (Shh)-driven medulloblastomas, suggesting that their unique gene signature includes the expression of distinctive transcript variants. Generally, we observed that tumor and normal fetal cerebellar samples shared significantly lower exon inclusion rates than normal adult cerebellum. We investigated whether tumor-associated splice forms were expressed in primary cultures of Shh-dependent mouse cerebellar granule cell precursors (GCP) and found that Shh caused a decrease in the cassette exon inclusion rate of five of the seven tested genes. Furthermore, we observed a significant increase in exon inclusion between postnatal days 7 and 14 of mouse cerebellar development, at the time when GCPs mature into postmitotic neurons. We conclude that inappropriate splicing frequently occurs in human medulloblastomas and may be linked to the activation of developmental signaling pathways and a failure of cerebellar precursor cells to differentiate. Cancer Res; 71(6); 2045–55. ©2011 AACR.
Data from Genome-Wide DNA Methylation Profiling of CpG Islands in Breast Cancer Identifies Novel Genes Associated with Tumorigenicity
Authors: Hill Victoria K. , Ricketts Christopher , Bieche Ivan , Vacher Sophie , Gentle Dean , Lewis Cheryl , Maher Eamonn R. , Latif Farida
Published: March 2023

Abstract
Epigenetic profiling of tumor DNAs may reveal important new theranostic targets to improve prognosis and treatment of advanced cancer patients. In this study, we performed a genome-wide profile of DNA methylation patterns in sporadic breast tumors by using the HumanMethylation27 BeadChips to assess relationships between DNA methylation changes and patient tumor characteristics. The arrays identified 264 hypermethylated loci/genes present in genomic CpG islands. Hierarchical clustering based on methylation levels divided the specimens into three distinct groups, within which certain clinical features also clustered. Statistically significant differences were determined between overall methylation levels of these clusters and estrogen receptor and progesterone receptor (ER/PR) status (P = 0.001), tumor relapse (P = 0.035), and lymph node metastasis (P = 0.042). We identified several individual methylated genes associated with clinical features, including six genes (RECK, SFRP2, UAP1L1, ACADL, ITR, and UGT3A1) that showed statistical significance between methylation and relapse-free survival. Notably, the RECK gene in this group has been associated in other cancers with poorest prognosis. Among the leading relapse-associated genes and the genes associated with ER/PR status, we sequenced an independent set of paired normal/tumor breast DNA samples to confirm tumor specificity of methylation. Further, we carried out quantitative real-time reverse transcriptase PCR to confirm reduced expression in methylated tumors. Our findings suggest the utility for the DNA methylation patterns in these genes as clinically useful surrogate markers in breast cancer, as well as new molecular pathways for further investigation as therapeutic targets. Cancer Res; 71(8); 2988–99. ©2011 AACR.
Data from Stromal Deletion of the APC Tumor Suppressor in Mice Triggers Development of Endometrial Cancer
Authors: Tanwar Pradeep S. , Zhang LiHua , Roberts Drucilla J. , Teixeira Jose M.
Published: March 2023

Abstract
The contribution of the stromal microenvironment to the progression of endometrial cancer has not been well explored. We have conditionally expressed a mutant allele of adenomatous polyposis coli (APCcKO) in murine uterine stroma cells to study its effect on uterine development and function. In addition to metrorrhagia, the mice develop complex atypical endometrial gland hyperplasia that progresses to endometrial carcinoma in situ and endometrial adenocarcinoma as evidenced by myometrial invasion. Stromal cells subjacent to the carcinoma cells express alpha-smooth muscle actin (αSMA) with fewer cells expressing platelet-derived growth factor α compared with normal stromal cells, suggesting that the mutant stromal cells have acquired a more myofibroblastic phenotype, which have been described as cancer-associated fibroblasts and have been shown to induce carcinogenesis in other organ systems. Analyses of human endometrial cancer specimens showed substantial αSMA expression in the stroma compared with normal endometrial stroma cells. We also show that APCcKO mutant uteri and human endometrial cancer have decreased stromal levels of transforming growth factor β and bone morphogenetic protein activities and that the mutant uteri failed to respond to exogenous estradiol stimulation. The mutant stroma cells also had higher levels of vascular endothelial growth factor and stromal derived factor signaling components and diminished expression of estrogen receptor α and progesterone receptor, which is common in advanced stages of human endometrial cancer and is an indicator of poor prognosis. Our results indicate that de novo mutation or loss of heterozygosity in stromal APC is sufficient to induce endometrial hyperplasia and endometrial carcinogenesis by mechanisms that are consistent with unopposed estrogen signaling in the endometrial epithelium. Cancer Res; 71(5); 1584–96. ©2011 AACR.
Data from Ror1 Is a Pseudokinase That Is Crucial for Met-Driven Tumorigenesis
Authors: Gentile Alessandra , Lazzari Luca , Benvenuti Silvia , Trusolino Livio , Comoglio Paolo M.
Published: March 2023

Abstract
The human kinome includes Ror1, a poorly characterized orphan receptor. Here we report the findings of an investigation of Ror1 contributions to cancer, undertaken through an integrated screening of 43 cancer cell lines where we measured protein expression, tyrosine phosphorylation, and growth response following RNAi-mediated Ror1 suppression. Ror1 was expressed in approximately 75% of the cancer cell lines without apparent histotype distribution. Gastric carcinoma cells (HS746T) and non–small cell lung carcinoma cells (NCI-H1993) exhibited high levels of Ror1 tyrosine phosphorylation, and Ror1 suppression caused growth inhibition. Biochemical assays revealed unexpectedly that Ror1 is a pseudokinase that is devoid of catalytic activity. Intriguingly, the two cell lines featuring tyrosine-phosphorylated Ror1 both exhibited amplification and activation of the Met oncogene. Ror1 phosphorylation was abrogated by Met inhibition, indicating Met-dependent transphosphorylation of Ror1. Conversely, Ror1 was not transphosphorylated by other constitutively active tyrosine kinases, including EGFR and ErbB2. Constitutive silencing of Ror1 in HS746T and NCI-H1993 carcinoma cells impaired proliferation in vitro and induced a dramatic inhibition of tumorigenesis in vivo. Together, our findings suggest a critical role for Ror1 in malignant phenotypes sustained by the Met oncogene. Cancer Res; 71(8); 3132–41. ©2011 AACR.
Data from Genetic Ablation of SOX18 Function Suppresses Tumor Lymphangiogenesis and Metastasis of Melanoma in Mice
Authors: Duong Tam , Proulx Steven T. , Luciani Paola , Leroux Jean-Christophe , Detmar Michael , Koopman Peter , Francois Mathias
Published: March 2023

Abstract
The lymphatic vasculature provides a major route for tumor metastasis and inhibiting neolymphangiogenesis induced by tumors can reduce metastasis in animal models. Developmental biology studies have identified the transcription factor SOX18 as a critical switch for lymphangiogenesis in the mouse embryo. Here, we show that SOX18 is also critical for tumor-induced lymphangiogenesis, and we show that suppressing SOX18 function is sufficient to impede tumor metastasis. Immunofluorescence analysis of murine tumor xenografts showed that SOX18 is reexpressed during tumor-induced neolymphangiogenesis. Tumors generated by implantation of firefly luciferase-expressing B16-F10 melanoma cells exhibited a reduced rate of metastasis to the regional draining lymph node in Sox18-deficient mice, as assessed by live bioluminescence imaging. Lower metastatic rates correlated with reduced tumoral lymphatic vessel density and diameter and with impaired drainage of peritumoral injected liposomes specific for lymph vessels from the sentinel lymph nodes. Overall, our findings suggested that SOX18 induction is a key step in mediating tumor lymphangiogenesis and metastasis, and they identify SOX18 as a potential therapeutic target for metastatic blockade. Cancer Res; 72(12); 3105–14. ©2012 AACR.
Data from Small RNA Sequencing and Functional Characterization Reveals MicroRNA-143 Tumor Suppressor Activity in Liposarcoma
Authors: Ugras Stacy , Brill Elliott , Jacobsen Anders , Hafner Markus , Socci Nicholas D. , DeCarolis Penelope L. , Khanin Raya , O'Connor Rachael , Mihailovic Aleksandra , Taylor Barry S. , Sheridan Robert , Gimble Jeffrey M. , Viale Agnes , Crago Aimee , Antonescu Cristina R. , Sander Chris , Tuschl Thomas , Singer Samuel
Published: March 2023

Abstract
Liposarcoma remains the most common mesenchymal cancer, with a mortality rate of 60% among patients with this disease. To address the present lack of therapeutic options, we embarked upon a study of microRNA (miRNA) expression alterations associated with liposarcomagenesis with the goal of exploiting differentially expressed miRNAs and the gene products they regulate as potential therapeutic targets. MicroRNA expression was profiled in samples of normal adipose tissue, well-differentiated liposarcoma, and dedifferentiated liposarcoma by both deep sequencing of small RNA libraries and hybridization-based Agilent microarrays. The expression profiles discriminated liposarcoma from normal adipose tissue and well differentiated from dedifferentiated disease. We defined over 40 miRNAs that were dysregulated in dedifferentiated liposarcomas in both the sequencing and the microarray analysis. The upregulated miRNAs included two cancer-associated species (miR-21 and miR-26a), and the downregulated miRNAs included two species that were highly abundant in adipose tissue (miR-143 and miR-145). Restoring miR-143 expression in dedifferentiated liposarcoma cells inhibited proliferation, induced apoptosis, and decreased expression of BCL2, topoisomerase 2A, protein regulator of cytokinesis 1 (PRC1), and polo-like kinase 1 (PLK1). The downregulation of PRC1 and its docking partner PLK1 suggests that miR-143 inhibits cytokinesis in these cells. In support of this idea, treatment with a PLK1 inhibitor potently induced G2–M growth arrest and apoptosis in liposarcoma cells. Taken together, our findings suggest that miR-143 re-expression vectors or selective agents directed at miR-143 or its targets may have therapeutic value in dedifferentiated liposarcoma. Cancer Res; 71(17); 5659–69. ©2011 AACR.
Data from COX-2 Blockade Suppresses Gliomagenesis by Inhibiting Myeloid-Derived Suppressor Cells
Authors: Fujita Mitsugu , Kohanbash Gary , Fellows-Mayle Wendy , Hamilton Ronald L. , Komohara Yoshihiro , Decker Stacy A. , Ohlfest John R. , Okada Hideho
Published: March 2023

Abstract
Epidemiologic studies have highlighted associations between the regular use of nonsteroidal anti-inflammatory drugs (NSAID) and reduced glioma risks in humans. Most NSAIDs function as COX-2 inhibitors that prevent production of prostaglandin E2 (PGE2). Because PGE2 induces expansion of myeloid-derived suppressor cells (MDSC), we hypothesized that COX-2 blockade would suppress gliomagenesis by inhibiting MDSC development and accumulation in the tumor microenvironment (TME). In mouse models of glioma, treatment with the COX-2 inhibitors acetylsalicylic acid (ASA) or celecoxib inhibited systemic PGE2 production and delayed glioma development. ASA treatment also reduced the MDSC-attracting chemokine CCL2 (C-C motif ligand 2) in the TME along with numbers of CD11b+Ly6GhiLy6Clo granulocytic MDSCs in both the bone marrow and the TME. In support of this evidence that COX-2 blockade blocked systemic development of MDSCs and their CCL2-mediated accumulation in the TME, there were defects in these processes in glioma-bearing Cox2-deficient and Ccl2-deficient mice. Conversely, these mice or ASA-treated wild-type mice displayed enhanced expression of CXCL10 (C-X-C motif chemokine 10) and infiltration of cytotoxic T lymphocytes (CTL) in the TME, consistent with a relief of MDSC-mediated immunosuppression. Antibody-mediated depletion of MDSCs delayed glioma growth in association with an increase in CXCL10 and CTLs in the TME, underscoring a critical role for MDSCs in glioma development. Finally, Cxcl10-deficient mice exhibited reduced CTL infiltration of tumors, establishing that CXCL10 limited this pathway of immunosuppression. Taken together, our findings show that the COX-2 pathway promotes gliomagenesis by directly supporting systemic development of MDSCs and their accumulation in the TME, where they limit CTL infiltration. Cancer Res; 71(7); 2664–74. ©2011 AACR.
Data from Select Heterozygous Keap1 Mutations Have a Dominant-Negative Effect on Wild-Type Keap1 In Vivo
Authors: Suzuki Takafumi , Maher Jonathan , Yamamoto Masayuki
Published: March 2023

Abstract
Under homeostatic conditions, Keap1 constitutively mediates the proteasomal degradation Nrf2. However, tertiary changes in Keap1 in response to the cellular environment allow for liberation of Nrf2 to transcriptionally regulate downstream cytoprotective genes that aid in cell survival. KEAP1/NRF2 somatic mutations causing constitutive NRF2 activation have been estimated to occur in approximately 25% of human lung tumors, with similar rates believed to exist in other tissue subtypes. As the stoichiometry between Keap1 and Nrf2 is 2:1, we hypothesized that heterozygous Keap1 mutations could suppress wild-type Keap1 (Keap1WT) activity by functioning as a dominant-negative protein through heterodimerization of mutant Keap1 (Keap1mutant) with Keap1WT. When Keap1G430C or Keap1G364C mutants were expressed in lieu of Keap1WT, premature juvenile mortality was observed. To test the hypothesis of a dominant-negative effect, Keap1-null mice were engineered to coexpress both Keap1WT and Keap1G430C transgenes, a phenotype analogous to that previously observed from a human lung tumor. These mice were viable, but phenotypically displayed hyperactivation of downstream Nrf2 target genes and moderate esophageal hyperkeratosis. Similar to the transgenic mouse Keap1G430C mutant, Keap1C273&288A substitutions also diminished Keap1WT activity in vivo. To further delineate involvement of the dominant-negative heterodimer, transgenic mice with a deletion or strategic mutation in Broad-complex, Tramtrack and Bric-a-Brac (BTB) domain that disallowed Keap1 dimerization were generated in the presence of Keap1WT, and failed to induce the dominant-negative effect in vivo. These results thus demonstrate that sequestration of Keap1WT into a Keap1mutant–Keap1WT heterodimer leads to a dominant-negative effect in vivo and gives rise to Nrf2 activation. Cancer Res; 71(5); 1700–9. ©2010 AACR.
Data from Cooperative Phosphorylation of FADD by Aur-A and Plk1 in Response to Taxol Triggers Both Apoptotic and Necrotic Cell Death
Authors: Jang Moon-Sun , Lee Su-Jin , Kang Nam Sook , Kim Eunhee
Published: March 2023

Abstract
Administration of the antimitotic chemotherapeutic taxol is known to cause accumulation of the mitotic kinase Aurora-A (Aur-A). Here, we report that Aur-A phosphorylates S203 of the Fas associated with death domain protein (FADD) in response to taxol treatment. In addition, polo-like kinase 1 (Plk1) failed to phosphorylate the Aur-A–unphosphorylatable FADD substitution mutant S203A, indicating that phosphorylation of S203 by Aur-A serves to prime FADD for Plk1-mediated phosphorylation at S194. The double-phosphorylation-mimicking mutant form of FADD, FADD-S194D/S203D (FADD-DD), recruited caspase-8, activating the caspase-dependent cell death pathway. FADD-DD also dissociated the cell death protein RIP1 from FADD, resulting in activation of RIP1 and triggering of caspase-independent cell death. Consistent with its death-promoting potential, FADD-DD showed robust tumor suppressor activity. However, single-phosphorylation-mimicking mutant forms of FADD, FADD-S194D/S203A (FADD-DA) and FADD-S194A/S203D (FADD-AD), were incapable of carrying out such functions, indicating that double phosphorylation of FADD is critical for the execution of cell death and tumor suppression. Collectively, our data show the existence of cooperative actions between Aur-A and Plk1 mitotic kinases in response to taxol, providing a molecular explanation for the action mechanism of taxol. Cancer Res; 71(23); 7207–15. ©2011 AACR.
Data from Parkin Pathway Activation Mitigates Glioma Cell Proliferation and Predicts Patient Survival
Authors: Yeo Calvin W.S. , Ng Felicia S.L. , Chai Chou , Tan Jeanne M.M. , Koh Geraldene R.H. , Chong Yuk Kien , Koh Lynnette W.H. , Foong Charlene S.F. , Sandanaraj Edwin , Holbrook Joanna D. , Ang Beng-Ti , Takahashi Ryosuke , Tang Carol , Lim Kah-Leong
Published: March 2023

Abstract
Mutations in the parkin gene, which encodes a ubiquitin ligase, are a major genetic cause of parkinsonism. Interestingly, parkin also plays a role in cancer as a putative tumor suppressor, and the gene is frequently targeted by deletion and inactivation in human malignant tumors. Here, we investigated a potential tumor suppressor role for parkin in gliomas. We found that parkin expression was dramatically reduced in glioma cells. Restoration of parkin expression promoted G1 phase cell-cycle arrest and mitigated the proliferation rate of glioma cells in vitro and in vivo. Notably, parkin-expressing glioma cells showed a reduction in levels of cyclin D1, but not cyclin E, and a selective downregulation of Akt serine-473 phosphorylation and VEGF receptor levels. In accordance, cells derived from a parkin-null mouse model exhibited increased levels of cyclin D1, VEGF receptor, and Akt phosphorylation, and divided significantly faster when compared with wild-type cells, with suppression of these changes following parkin reintroduction. Clinically, analysis of parkin pathway activation was predictive for the survival outcome of patients with glioma. Taken together, our study provides mechanistic insight into the tumor suppressor function of parkin in brain tumors and suggests that measurement of parkin pathway activation may be used clinically as a prognostic tool in patients with brain tumor. Cancer Res; 72(10); 2543–53. ©2012 AACR.
Data from Overexpression of a Novel Activator of PAK4, the CDK5 Kinase–Associated Protein CDK5RAP3, Promotes Hepatocellular Carcinoma Metastasis
Authors: Mak Grace Wing-Yan , Chan Mandy Man-Lok , Leong Veronica Yee-Law , Lee Joyce Man-Fong , Yau Tai-On , Ng Irene Oi-Lin , Ching Yick-Pang
Published: March 2023

Abstract
The CDK5 kinase regulatory subunit-associated protein 3 (CDK5RAP3 or C53/LZAP) regulates apoptosis induced by genotoxic stress. Although CDK5RAP3 has been implicated in cancer progression, its exact role in carcinogenesis is not well established. In this article, we report that CDK5RAP3 has an important prometastatic function in hepatocarcinogenesis. An examination of human hepatocellular carcinoma (HCC) samples revealed at least twofold overexpression of CDK5RAP3 transcripts in 58% (39/67) of HCC specimens when compared with corresponding nontumorous livers. CDK5RAP3 overexpression was associated with more aggressive biological behavior. In HCC cell lines, stable overexpression of CDK5RAP3 promoted, and small interfering RNA–mediated knockdown inhibited, tumorigenic activity and metastatic potential. We found that overexpression of CDK5RAP3 and p21-activated protein kinase 4 (PAK4) correlated in human HCCs, and that CDK5RAP3 was a novel binding partner of PAK4, and this binding enhanced PAK4 activity. siRNA-mediated knockdown of PAK4 in CDK5RAP3-expressing HCC cells reversed the enhanced cell invasiveness mediated by CDK5RAP3 overexpression, implying that PAK4 is essential for CDK5RAP3 function. Taken together, our findings reveal that CDK5RAP3 is widely overexpressed in HCC and that overexpression of CDK5RAP3 promotes HCC metastasis through PAK4 activation. Cancer Res; 71(8); 2949–58. ©2011 AACR.
Data from Spontaneous Cytotoxic T-Cell Reactivity against Indoleamine 2,3-Dioxygenase-2
Authors: Sørensen Rikke Bæk , Køllgaard Tania , Andersen Rikke Sick , van den Berg Joost Huibert , Svane Inge Marie , Straten Per thor , Andersen Mads Hald
Published: March 2023

Abstract
Several lines of data have suggested a possible link between the indoleamine 2,3-dioxygenase (IDO)-like protein IDO2 and cancer. First, IDO2 expression has been described in human tumors, including renal, gastric, colon, and pancreatic tumors. Second, the apparent selective inhibition of IDO2 by the D stereoisomer of the IDO blocker 1-methyl-tryptophan (1MT), which tends to be more active than the L-isomer in a variety of biological assays for IDO function, suggests that IDO2 may be important to sustain immune escape and growth of tumors. Especially, D-1MT heightens chemotherapeutic efficacy in mouse models of cancer in a nontoxic fashion. Here, we describe the immunogenicity of IDO2 by showing the presence of spontaneous cytotoxic T-cell reactivity against IDO2 in peripheral blood of both healthy donors and cancer patients. Furthermore, we show that these IDO2-specific T cells are cytotoxic effector cells that recognize and kill tumor cells. Our data suggest that IDO2 might be a useful target for anticancer immunotherapeutic strategies. Cancer Res; 71(6); 2038–44. ©2011 AACR.
Data from High Basal Nuclear Levels of Nrf2 in Acute Myeloid Leukemia Reduces Sensitivity to Proteasome Inhibitors
Authors: Rushworth Stuart A. , Bowles Kristian M. , MacEwan David J.
Published: March 2023

Abstract
Proteasome inhibitors such as bortezomib exhibit clinical efficacy in multiple myeloma, but studies in acute myeloid leukemia (AML) have been disappointing to date. The apparent failure in AML likely reflects a lack of biological understanding that might clarify applications of proteosome inhibitors in this disease. Here we show that AML cells are considerably less sensitive than control noncancerous cells to bortezomib-induced cytotoxicity, permitting most bortezomib-treated AML cells to survive treatment. We traced reduced bortezomib sensitivity to increased basal levels of nuclear Nrf2, a transcription factor that stimulates protective antioxidant enzymes. Bortezomib stimulates cytotoxicity through accumulation of reactive oxygen species (ROS) but elevated basal levels of nuclear Nrf2 present in AML cells reduced ROS levels, permitting AML cells to survive drug treatment. We further found that the Nrf2 transcriptional repressor Bach1 is rapidly inactivated by bortezomib, allowing rapid induction of Nrf2-regulated cytoprotective and detoxification genes that protect AML cells from bortezomib-induced apoptosis. By contrast, nonmalignant control cells lacked constitutive activation of Nrf2, such that bortezomib-mediated inactivation of Bach1 led to a delay in induction of Nrf2-regulated genes, effectively preventing the manifestation of apoptotic protection that is seen in AML cells. Together, our findings argue that AML might be rendered sensitive to proteasome inhibitors by cotreatment with either an Nrf2-inhibitory or Bach1-inhibitory treatment, rationalizing a targeted therapy against AML. Cancer Res; 71(5); 1999–2009. ©2011 AACR.