bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Thymoquinone Triggers Inactivation of the Stress Response Pathway Sensor CHEK1 and Contributes to Apoptosis in Colorectal Cancer Cells
Authors: Gali-Muhtasib Hala , Kuester Doerthe , Mawrin Christian , Bajbouj Khuloud , Diestel Antje , Ocker Matthias , Habold Caroline , Foltzer-Jourdainne Charlotte , Schoenfeld Peter , Peters Brigitte , Diab-Assaf Mona , Pommrich Ulf , Itani Wafica , Lippert Hans , Roessner Albert , Schneider-Stock Regine
Published: March 2023

Abstract
There are few reports describing the role of p53-dependent gene repression in apoptotic cell death. To identify such apoptosis-associated p53 target genes, we used the pro-oxidant plant-derived drug thymoquinone and compared p53+/+ and p53−/− colon cancer cells HCT116. The p53 wild-type (wt) status correlated with more pronounced DNA damage and higher apoptosis after thymoquinone treatment. A significant up-regulation of the survival gene CHEK1 was observed in p53−/− cells in response to thymoquinone due to the lack of transcriptional repression of p53. In p53−/− cells, transfection with p53-wt vector and CHEK1 small interfering RNA treatment decreased CHEK1 mRNA and protein levels and restored apoptosis to the levels of the p53+/+ cells. p53−/− cells transplanted to nude mice treated with thymoquinone up-regulated CHEK1 expression and did not undergo apoptosis unlike p53+/+ cells. Immunofluorescence analysis revealed that the apoptosis resistance in p53−/− cells after thymoquinone treatment might be conveyed by shuttling of CHEK1 into the nucleus. We confirmed the in vivo existence of this CHEK1/p53 link in human colorectal cancer, showing that tumors lacking p53 had higher levels of CHEK1, which was accompanied by poorer apoptosis. CHEK1 overexpression was correlated with advanced tumor stages (P = 0.03), proximal tumor localization (P = 0.02), and worse prognosis (1.9-fold risk, univariate Cox regression; Kaplan-Meier, P = 0.04). We suggest that the inhibition of the stress response sensor CHEK1 might contribute to the antineoplastic activity of specific DNA-damaging drugs. [Cancer Res 2008;68(14):5609–18]
Data from Breast Tumor Kinase Phosphorylates p190RhoGAP to Regulate Rho and Ras and Promote Breast Carcinoma Growth, Migration, and Invasion
Authors: Shen Che-Hung , Chen Hsin-Yi , Lin Ming-Shien , Li Fang-Yen , Chang Cheng-Chi , Kuo Min-Liang , Settleman Jeffrey , Chen Ruey-Hwa
Published: March 2023

Abstract
Breast tumor kinase (Brk), an Src-like nonreceptor tyrosine kinase, is overexpressed in breast cancer and several other cancer types. Our previous study indicates that Brk promotes cell migration and tumor invasion by phosphorylating the focal adhesion protein paxillin. Here, we report the identification of p190RhoGAP-A (p190) as a Brk substrate. Brk phosphorylates p190 at the Y1105 residue both in vitro and in vivo, thereby promoting the association of p190 with p120RasGAP (p120). As a consequence, Brk stimulates p190 and attenuates p120 functions, leading to RhoA inactivation and Ras activation, respectively. In carcinoma cells expressing high levels of Brk, endogenous Brk functions as a key contributor to epidermal growth factor–induced p190 tyrosine phosphorylation. We present evidence showing that p190 phosphorylation plays essential roles in both migratory and proliferative effects of Brk. Furthermore, disruption of p190 phosphorylation–induced p190/p120 complex in breast cancer cells abolishes not only the abilities of Brk to regulate RhoA and Ras but also the stimulatory effects of Brk on proliferation, migration, invasion, transformation, and tumorigenicity. Together, our findings reveal a previously unknown function of Brk in regulating both RhoA and Ras by phosphorylating p190 and provide evidence for the crucial roles of this Brk-elicited signaling pathway in promoting breast malignancy. [Cancer Res 2008;68(19):7779–87]
Data from The Origins of Breast Cancer Prognostic Gene Expression Profiles
Authors: Lukes Luanne , Crawford Nigel P.S. , Walker Renard , Hunter Kent W.
Published: March 2023

Abstract
Recent high profile clinical trials show that microarray-based gene expression profiling has the potential to become an important tool for predicting prognosis in breast cancer. Earlier work in our laboratory using mouse models and human breast cancer populations has enabled us to show that metastasis susceptibility is an inherited trait. This same combined approach facilitated the identification of a number of candidate genes that, when dysregulated, have the potential to induce prognostic gene expression profiles in human data sets. To investigate if these gene expression signatures were of somatic or germline origin and to assess the contribution of different cell types to the induction of these signatures, we have performed a series of expression profiling experiments in a mouse model of metastatic breast cancer. These results show that both the tumor epithelium and invading stromal tissues contribute to the development of prognostic gene signatures. Furthermore, analysis of normal tissues and tumor transplants suggests that prognostic signatures result from both somatic and inherited components, with the inherited components being more consistently predictive. [Cancer Res 2009;69(1):310–8]
Data from Isoaspartate-Glycine-Arginine: A New Tumor Vasculature–Targeting Motif
Authors: Curnis Flavio , Sacchi Angelina , Gasparri Anna , Longhi Renato , Bachi Angela , Doglioni Claudio , Bordignon Claudio , Traversari Catia , Rizzardi Gian-Paolo , Corti Angelo
Published: March 2023

Abstract
Asparagine deamidation in peptides or in fibronectin fragments containing the asparagine-glycine-arginine sequence generates isoaspartate-glycine-arginine (isoDGR), a new αvβ3 integrin-binding motif. Because αvβ3 is expressed in angiogenic vessels, we hypothesized that isoDGR-containing peptides could be exploited as ligands for targeted delivery of drugs to tumor neovasculature. We found that a cyclic CisoDGRC peptide coupled to fluorescent nanoparticles (quantum dots) could bind αvβ3 integrin and colocalize with anti-CD31, anti-αvβ3, and anti-α5β1 antibodies in human renal cell carcinoma tissue sections, indicating that this peptide could efficiently recognize endothelial cells of angiogenic vessels. Using CisoDGRC fused to tumor necrosis factor α (TNF) we observed that ultralow doses (1–10 pg) of this product (called isoDGR-TNF), but not of TNF or CDGRC-TNF fusion protein, were sufficient to induce antitumor effects when administered alone or in combination with chemotherapy to tumor-bearing mice. The antitumor activity of isoDGR-TNF was efficiently inhibited by coadministration with an excess of free CisoDGRC, as expected for ligand-directed targeting mechanisms. These results suggest that isoDGR is a novel tumor vasculature–targeting motif. Peptides containing isoDGR could be exploited as ligands for targeted delivery of drugs, imaging agents, or other compounds to tumor vasculature. [Cancer Res 2008;68(17):7073–82]
Data from Interleukin-15/Interleukin-15Rα Complexes Promote Destruction of Established Tumors by Reviving Tumor-Resident CD8+ T Cells
Authors: Epardaud Mathieu , Elpek Kutlu G. , Rubinstein Mark P. , Yonekura Ai-ris , Bellemare-Pelletier Angelique , Bronson Roderick , Hamerman Jessica A. , Goldrath Ananda W. , Turley Shannon J.
Published: March 2023

Abstract
Tumors often escape immune-mediated destruction by suppressing lymphocyte infiltration or effector function. New approaches are needed that overcome this suppression and thereby augment the tumoricidal capacity of tumor-reactive lymphocytes. The cytokine interleukin-15 (IL-15) promotes proliferation and effector capacity of CD8+ T cells, natural killer (NK) cells, and NKT cells; however, it has a short half-life and high doses are needed to achieve functional responses in vivo. The biological activity of IL-15 can be dramatically increased by complexing this cytokine to its soluble receptor, IL-15Rα. Here, we report that in vivo delivery of IL-15/IL-15Rα complexes triggers rapid and significant regression of established solid tumors in two murine models. Despite a marked expansion of IL-2/IL-15Rβ+ cells in lymphoid organs and peripheral blood following treatment with IL-15/IL-15Rα complexes, the destruction of solid tumors was orchestrated by tumor-resident rather than newly infiltrating CD8+ T cells. Our data provide novel insights into the use of IL-15/IL-15Rα complexes to relieve tumor-resident T cells from functional suppression by the tumor microenvironment and have significant implications for cancer immunotherapy and treatment of chronic infections. [Cancer Res 2008;68(8):2972–83]
Data from Functional Characterization of Filamin A Interacting Protein 1–Like, a Novel Candidate for Antivascular Cancer Therapy
Authors: Kwon Mijung , Hanna Engy , Lorang Dominique , He Mei , Quick John S. , Adem Asha , Stevenson Christina , Chung Joon-Yong , Hewitt Stephen M. , Zudaire Enrique , Esposito Dominic , Cuttitta Frank , Libutti Steven K.
Published: March 2023

Abstract
Inhibiting angiogenesis has become a major therapeutic strategy for cancer treatment. To identify common intracellular mediators, we previously analyzed gene expression profiles of endothelial cells after treatment with angiogenesis inhibitors. Filamin A interacting protein 1-like (FILIP1L; previously known as down-regulated in ovarian cancer 1) was identified as one of the genes up-regulated in endothelial cells in response to these inhibitors. However, the expression and function of FILIP1L protein is uncharacterized. Here, we provide the first description of the expression and specific subcellular localization of FILIP1L protein in human tissue. Overexpression of FILIP1L resulted in inhibition of cell proliferation and migration and increased apoptosis. In addition, overexpression of FILIP1L truncation mutants showed differential antiproliferative activity. A COOH terminal truncation mutant (FILIP1LΔC103) was more potent than wild-type FILIP1L in mediating this activity. Targeted expression of FILIP1LΔC103 in tumor vasculature inhibited tumor growth in vivo. Overall, these findings suggest that the novel protein FILIP1L may be an important mediator of the effects of angiogenesis inhibitors and that FILIP1L has the potential to be an antivascular reagent for cancer therapy. [Cancer Res 2008;68(18):7332–41]
Data from Interaction of Muc2 and Apc on Wnt Signaling and in Intestinal Tumorigenesis: Potential Role of Chronic Inflammation
Authors: Yang Kan , Popova Natalia V. , Yang Wan Cai , Lozonschi Ioanna , Tadesse Selam , Kent Scott , Bancroft Laura , Matise Ilze , Cormier Robert T. , Scherer Stefan J. , Edelmann Winfried , Lipkin Martin , Augenlicht Leonard , Velcich Anna
Published: March 2023

Abstract
Somatic mutations of the adenomatous polyposis coli (APC) gene are initiating events in the majority of sporadic colon cancers. A common characteristic of such tumors is reduction in the number of goblet cells that produce the mucin MUC2, the principal component of intestinal mucus. Consistent with these observations, we showed that Muc2 deficiency results in the spontaneous development of tumors along the entire gastrointestinal tract, independently of deregulated Wnt signaling. To dissect the complex interaction between Muc2 and Apc in intestinal tumorigenesis and to elucidate the mechanisms of tumor formation in Muc2−/− mice, we crossed the Muc2−/− mouse with two mouse models, Apc1638N/+ and ApcMin/+, each of which carries an inactivated Apc allele. The introduction of mutant Muc2 into Apc1638N/+ and ApcMin/+ mice greatly increased transformation induced by the Apc mutation and significantly shifted tumor development toward the colon as a function of Muc2 gene dosage. Furthermore, we showed that in compound double mutant mice, deregulation of Wnt signaling was the dominant mechanism of tumor formation. The increased tumor burden in the distal colon of Muc2/Apc double mutant mice was similar to the phenotype observed in ApcMin/+ mice that are challenged to mount an inflammatory response, and consistent with this, gene expression profiles of epithelial cells from flat mucosa of Muc2-deficient mice suggested that Muc2 deficiency was associated with low levels of subclinical chronic inflammation. We hypothesize that Muc2−/− tumors develop through an inflammation-related pathway that is distinct from and can complement mechanisms of tumorigenesis in Apc+/− mice. [Cancer Res 2008;68(18):7313–22]
Data from Methylation of TFPI2 in Stool DNA: A Potential Novel Biomarker for the Detection of Colorectal Cancer
Authors: Glöckner Sabine C. , Dhir Mashaal , Yi Joo Mi , McGarvey Kelly E. , Van Neste Leander , Louwagie Joost , Chan Timothy A. , Kleeberger Wolfram , de Bruïne Adriaan P. , Smits Kim M. , Khalid-de Bakker Carolina A.J. , Jonkers Daisy M.A.E. , Stockbrügger Reinhold W. , Meijer Gerrit A. , Oort Frank A. , Iacobuzio-Donahue Christine , Bierau Katja , Herman James G. , Baylin Stephen B. , Van Engeland Manon , Schuebel Kornel E. , Ahuja Nita
Published: March 2023

Abstract
We have used a gene expression array–based strategy to identify the methylation of tissue factor pathway inhibitor 2 (TFPI2), a potential tumor suppressor gene, as a frequent event in human colorectal cancers (CRC). TFPI2 belongs to the recently described group of embryonic cell Polycomb group (PcG)–marked genes that may be predisposed to aberrant DNA methylation in early stages of colorectal carcinogenesis. Aberrant methylation of TFPI2 was detected in almost all CRC adenomas (97%, n = 56) and stages I to IV CRCs (99%, n = 115). We further explored the potential of TFPI2 as a biomarker for the early detection of CRC using stool DNA–based assays in patients with nonmetastatic CRC and average-risk noncancer controls who were candidates for screening. TFPI2 methylation was detected in stool DNA from stage I to III CRC patients with a sensitivity of 76% to 89% and a specificity of 79% to 93%. Detection of TFPI2 methylation in stool DNA may act as a useful adjunct to the noninvasive strategies for screening of CRCs in the future. [Cancer Res 2009;69(11):4691–9]
Data from Development of Resistance to Targeted Therapies Transforms the Clinically Associated Molecular Profile Subtype of Breast Tumor Xenografts
Authors: Creighton Chad J. , Massarweh Suleiman , Huang Shixia , Tsimelzon Anna , Hilsenbeck Susan G. , Osborne C. Kent , Shou Jiang , Malorni Luca , Schiff Rachel
Published: March 2023

Abstract
The effectiveness of therapies targeting specific pathways in breast cancer, such as the estrogen receptor or HER2, is limited because many tumors manifest resistance, either de novo or acquired, during the course of treatment. To investigate molecular mechanisms of resistance, we used two xenograft models of estrogen receptor–positive (ER+) breast cancer, one with and one without HER2 overexpression (MCF7/HER2-18 and MCF7 wt, respectively). Mice with established tumors were assigned to the following treatment groups: estrogen supplementation (E2), estrogen deprivation (ED), ED plus tamoxifen (Tam), all with or without the epidermal growth factor receptor tyrosine kinase inhibitor gefitinib (G). Another group received ED plus the antiestrogen fulvestrant (MCF7 wt only). Tumors with acquired or de novo resistance to these endocrine therapies were profiled for gene expression and compared with tumors in the E2 control group. One class of genes underexpressed in endocrine-resistant tumors (relative to E2-treated tumors) were estrogen inducible in vitro and associated with ER+ human breast cancers (luminal subtype). Another class of genes overexpressed in tumors with acquired resistance in both models represented transcriptional targets of HER2 signaling and was associated with ER−/HER2+ human cancers (ERBB2+ subtype). A third class of genes overexpressed in MCF7/HER2-18 tumors exhibiting de novo resistance to tamoxifen was associated with ER+ human cancers but not with estrogen-regulated genes. Thus, in response to various endocrine therapy regimens, these xenograft breast tumors shut down classic estrogen signaling and activate alternative pathways such as HER2 that contribute to treatment resistance. Over time, the molecular phenotype of breast cancer can change. [Cancer Res 2008;68(18):7493–501]
Data from Epigenetic Profiles Distinguish Pleural Mesothelioma from Normal Pleura and Predict Lung Asbestos Burden and Clinical Outcome
Authors: Christensen Brock C. , Houseman E.A. , Godleski John J. , Marsit Carmen J. , Longacker Jennifer L. , Roelofs Cora R. , Karagas Margaret R. , Wrensch Margaret R. , Yeh Ru-Fang , Nelson Heather H. , Wiemels Joe L. , Zheng Shichun , Wiencke John K. , Bueno Raphael , Sugarbaker David J. , Kelsey Karl T.
Published: March 2023

Abstract
Mechanisms of action of nonmutagenic carcinogens such as asbestos remain poorly characterized. As pleural mesothelioma is known to have limited numbers of genetic mutations, we aimed to characterize the relationships among gene-locus–specific methylation alterations, disease status, asbestos burden, and survival in this rapidly fatal asbestos-associated tumor. Methylation of 1505 CpG loci associated with 803 cancer-related genes were studied in 158 pleural mesotheliomas and 18 normal pleura. After false-discovery rate correction, 969 CpG loci were independently associated with disease status (Q < 0.05). Classifying samples based on CpG methylation profile with a mixture model approach, methylation classes discriminated tumor from normal pleura (permutation P < 0.0001). In a random forests classification, the overall misclassification error rate was 3.4%, with <1% (n = 1) of tumors misclassified as normal (P < 0.0001). Among tumors, methylation class membership was significantly associated with lung tissue asbestos body burden (P < 0.03), and significantly predicted survival (likelihood ratio P < 0.01). Consistent with prior work, asbestos burden was associated with an increased risk of death (hazard ratio, 1.4; 95% confidence interval, 1.1–1.8). Our results have shown that methylation profiles powerfully differentiate diseased pleura from nontumor pleura and that asbestos burden and methylation profiles are independent predictors of mesothelioma patient survival. We have added to the growing body of evidence that cellular epigenetic dysregulation is a critical mode of action for asbestos in the induction of pleural mesothelioma. Importantly, these findings hold great promise for using epigenetic profiling in the diagnosis and prognosis of human cancers. [Cancer Res 2009;69(1):227–34]
Data from Interleukin-6 in the Bone Marrow Microenvironment Promotes the Growth and Survival of Neuroblastoma Cells
Authors: Ara Tasnim , Song Liping , Shimada Hiroyuki , Keshelava Nino , Russell Heidi V. , Metelitsa Leonid S. , Groshen Susan G. , Seeger Robert C. , DeClerck Yves A.
Published: March 2023

Abstract
Neuroblastoma, the second most common solid tumor in children, frequently metastasizes to the bone marrow and the bone. Neuroblastoma cells present in the bone marrow stimulate the expression of interleukin-6 (IL-6) by bone marrow stromal cells (BMSC) to activate osteoclasts. Here we have examined whether stromal-derived IL-6 also has a paracrine effect on neuroblastoma cells. An analysis of the expression of IL-6 and its receptor, IL-6R, in 11 neuroblastoma cell lines indicated the expression of IL-6 in 4 cell lines and of IL-6R in 9 cell lines. Treatment of IL-6R–positive cells with recombinant human IL-6 resulted in signal transducer and activator of transcription-3 and extracellular signal–regulated kinase-1/2 activation. Culturing IL-6R–positive neuroblastoma cells in the presence of BMSC or recombinant human IL-6 increased proliferation and protected tumor cells from etoposide-induced apoptosis, whereas it had no effect on IL-6R–negative tumor cells. In vivo, neuroblastoma tumors grew faster in the presence of a paracrine source of IL-6. IL-6 induced the expression of cyclooxygenase-2 in neuroblastoma cells with concomitant release of prostaglandin-E2, which increased the expression of IL-6 by BMSC. Supporting a role for stromal-derived IL-6 in patients with neuroblastoma bone metastasis, we observed elevated levels of IL-6 in the serum and bone marrow of 16 patients with neuroblastoma bone metastasis and in BMSC derived from these patients. Altogether, the data indicate that stromal-derived IL-6 contributes to the formation of a bone marrow microenvironment favorable to the progression of metastatic neuroblastoma. [Cancer Res 2009;69(1):329–37]
Data from Defining a Chromatin Pattern that Characterizes DNA-Hypermethylated Genes in Colon Cancer Cells
Authors: McGarvey Kelly M. , Van Neste Leander , Cope Leslie , Ohm Joyce E. , Herman James G. , Van Criekinge Wim , Schuebel Kornel E. , Baylin Stephen B.
Published: March 2023

Abstract
Epigenetic gene regulation is a key determinant of heritable gene expression patterns and is critical for normal cellular function. Dysregulation of epigenetic transcriptional control is a fundamental feature of cancer, particularly manifesting as increased promoter DNA methylation with associated aberrant gene silencing, which plays a significant role in tumor progression. We now globally map key chromatin parameters for genes with promoter CpG island DNA hypermethylation in colon cancer cells by combining microarray gene expression analyses with chromatin immunoprecipitation-on-chip technology. We first show that the silent state of such genes universally correlates with a broad distribution of a low but distinct level of the PcG-mediated histone modification, methylation of lysine 27 of histone 3 (H3K27me), and a very low level of the active mark H3K4me2. This chromatin pattern, and particularly H3K4me2 levels, crisply separates DNA-hypermethylated genes from those where histone deacetylation is responsible for transcriptional silencing. Moreover, the chromatin pattern can markedly enhance identification of truly silent and DNA-hypermethylated genes. We additionally find that when DNA-hypermethylated genes are demethylated and reexpressed, they adopt a bivalent chromatin pattern, which is associated with the poised gene expression state of a large group of embryonic stem cell genes and is characterized by an increase in levels of both the H3K27me3 and H3K4me2 marks. Our data have great relevance for the increasing interest in reexpression of DNA-hypermethylated genes for the treatment of cancer. [Cancer Res 2008;68(14):5753–9]
Data from N-Myc Regulates a Widespread Euchromatic Program in the Human Genome Partially Independent of Its Role as a Classical Transcription Factor
Authors: Cotterman Rebecca , Jin Victor X. , Krig Sheryl R. , Lemen Jessica M. , Wey Alice , Farnham Peggy J. , Knoepfler Paul S.
Published: March 2023

Abstract
Myc proteins have long been modeled to operate strictly as classic gene-specific transcription factors; however, we find that N-Myc has a robust role in the human genome in regulating global cellular euchromatin, including that of intergenic regions. Strikingly, 90% to 95% of the total genomic euchromatic marks histone H3 acetylated at lysine 9 and methylated at lysine 4 is N-Myc–dependent. However, Myc regulation of transcription, even of genes it directly binds and at which it is required for the maintenance of active chromatin, is generally weak. Thus, Myc has a much more potent ability to regulate large domains of euchromatin than to influence the transcription of individual genes. Overall, Myc regulation of chromatin in the human genome includes both specific genes, but also expansive genomic domains that invoke functions independent of a classic transcription factor. These findings support a new dual model for Myc chromatin function with important implications for the role of Myc in cancer and stem cell biology, including that of induced pluripotent stem cells. [Cancer Res 2008;68(23):9654–62]
Data from Membrane Type 1 Matrix Metalloproteinase–Mediated Stromal Syndecan-1 Shedding Stimulates Breast Carcinoma Cell Proliferation
Authors: Su Gui , Blaine Stacy A. , Qiao Dianhua , Friedl Andreas
Published: March 2023

Abstract
Mounting evidence implicates stromal fibroblasts in breast carcinoma progression. We have recently shown in three-dimensional coculture experiments that human mammary fibroblasts stimulate the proliferation of T47D breast carcinoma cells and that this activity requires the shedding of the heparan sulfate proteoglycan syndecan-1 (Sdc1) from the fibroblast surface. The goal of this project was to determine the mechanism of Sdc1 ectodomain shedding. The broad spectrum matrix metalloproteinase (MMP) inhibitor GM6001 specifically blocked Sdc1-mediated carcinoma cell growth stimulation, pointing toward MMPs as critical enzymes involved in Sdc1 shedding. MMP-2 and membrane type 1 MMP (MT1-MMP) were the predominant MMPs expressed by the mammary fibroblasts. Fibroblast-dependent carcinoma cell growth stimulation in three-dimensional coculture was abolished by MT1-MMP expression silencing with small interfering RNA and restored either by adding recombinant MT1-MMP catalytic domain or by expressing a secreted form of Sdc1 in the fibroblasts. These findings are consistent with a model where fibroblast-derived MT1-MMP cleaves Sdc1 at the fibroblast surface, leading to paracrine growth stimulation of carcinoma cells by Sdc1 ectodomain. The relevance of MT1-MMP in paracrine interactions was further supported by coculture experiments with T47D cells and primary fibroblasts isolated from human breast carcinomas or matched normal breast tissue. Carcinoma-associated fibroblasts stimulated T47D cell proliferation significantly more than normal fibroblasts in three-dimensional coculture. Function-blocking anti–MT1-MMP antibody significantly inhibited the T47D cell growth stimulation in coculture with primary fibroblasts. In summary, these results ascribe a novel role to fibroblast-derived MT1-MMP in stromal-epithelial signaling in breast carcinomas. [Cancer Res 2008;68(22):9558–65]
Data from A Subset of Host B Lymphocytes Controls Melanoma Metastasis through a Melanoma Cell Adhesion Molecule/MUC18-Dependent Interaction: Evidence from Mice and Humans
Authors: Staquicini Fernanda I. , Tandle Anita , Libutti Steven K. , Sun Jessica , Zigler Maya , Bar-Eli Menashe , Aliperti Fabiana , Pérez Elizabeth C. , Gershenwald Jeffrey E. , Mariano Mario , Pasqualini Renata , Arap Wadih , Lopes José Daniel
Published: March 2023

Abstract
Host immunity affects tumor metastasis but the corresponding cellular and molecular mechanisms are not entirely clear. Here, we show that a subset of B lymphocytes (termed B-1 population), but not other lymphocytes, has prometastatic effects on melanoma cells in vivo through a direct heterotypic cell-cell interaction. In the classic B16 mouse melanoma model, one mechanism underlying this phenomenon is a specific up-regulation and subsequent homophilic interaction mediated by the cell surface glycoprotein MUC18 (also known as melanoma cell adhesion molecule). Presence of B-1 lymphocytes in a panel of tumor samples from melanoma patients directly correlates with MUC18 expression in melanoma cells, indicating that the same protein interaction exists in humans. These results suggest a new but as yet unrecognized functional role for host B-1 lymphocytes in tumor metastasis and establish a biochemical basis for such observations. Our findings support the counterintuitive central hypothesis in which a primitive layer of the immune system actually contributes to tumor progression and metastasis in a mouse model and in melanoma patients. Given that monoclonal antibodies against MUC18 are in preclinical development but the reason for their antitumor activity is not well understood, these translational results are relevant in the setting of human melanoma and perhaps of other cancers. [Cancer Res 2008;68(20):8419–28]
Data from COOH-Terminal Binding Protein Regulates Expression of the p16INK4A Tumor Suppressor and Senescence in Primary Human Cells
Authors: Mroz Edmund A. , Baird Abigail H. , Michaud William A. , Rocco James W.
Published: March 2023

Abstract
The p16/pocket-protein pathway sets a balance between tumor suppression and capacity for tissue regeneration. Understanding the upstream signaling pathway that turns on the expression of p16 is required both for knowing the tumorigenic stresses from which this pathway provides protection and for appreciating the selective pressure that leads to the loss of this pathway in most human tumors. We report that COOH-terminal binding protein (CtBP), a physiologically regulated transcriptional corepressor that dimerizes to hold together repressive complexes, regulates p16 expression in primary human fibroblasts and keratinocytes. Interfering with CtBP-mediated repression increased p16 expression and accelerated senescence. CtBP had little influence on the expression of the alternate product of the CDKN2A tumor-suppressor gene, p14ARF. Loss of CtBP-mediated repression diminished the Polycomb-based epigenetic histone mark that is reported to favor silencing of p16 via DNA methylation. Enhancing CtBP-mediated repression by growing cells in low oxygen increased the association of CtBP with the p16 promoter, as assessed by chromatin immunoprecipitation, and reduced p16 expression. Stresses and stimuli that reduce CtBP-mediated repression are associated with increased p16 expression; therefore, CtBP may provide a common final target for regulating the balance among tumor suppression, regenerative capacity, and senescence. [Cancer Res 2008;68(15):6049–53]
Data from Atu027, a Liposomal Small Interfering RNA Formulation Targeting Protein Kinase N3, Inhibits Cancer Progression
Authors: Aleku Manuela , Schulz Petra , Keil Oliver , Santel Ansgar , Schaeper Ute , Dieckhoff Britta , Janke Oliver , Endruschat Jens , Durieux Birgit , Röder Nadine , Löffler Kathrin , Lange Christian , Fechtner Melanie , Möpert Kristin , Fisch Gerald , Dames Sibylle , Arnold Wolfgang , Jochims Karin , Giese Klaus , Wiedenmann Bertram , Scholz Arne , Kaufmann Jörg
Published: March 2023

Abstract
We have previously described a small interfering RNA (siRNA) delivery system (AtuPLEX) for RNA interference (RNAi) in the vasculature of mice. Here we report preclinical data for Atu027, a siRNA-lipoplex directed against protein kinase N3 (PKN3), currently under development for the treatment of advanced solid cancer. In vitro studies revealed that Atu027-mediated inhibition of PKN3 function in primary endothelial cells impaired tube formation on extracellular matrix and cell migration, but is not essential for proliferation. Systemic administration of Atu027 by repeated bolus injections or infusions in mice, rats, and nonhuman primates results in specific, RNAi-mediated silencing of PKN3 expression. We show the efficacy of Atu027 in orthotopic mouse models for prostate and pancreatic cancers with significant inhibition of tumor growth and lymph node metastasis formation. The tumor vasculature of Atu027-treated animals showed a specific reduction in lymph vessel density but no significant changes in microvascular density. [Cancer Res 2008;68(23):9788–98]
Data from Milk Fat Globule EGF-8 Promotes Melanoma Progression through Coordinated Akt and Twist Signaling in the Tumor Microenvironment
Authors: Jinushi Masahisa , Nakazaki Yukoh , Carrasco Daniel R. , Draganov Dobrin , Souders Nicholas , Johnson Matthew , Mihm Martin C. , Dranoff Glenn
Published: March 2023

Abstract
The pathogenesis of malignant melanoma involves the interplay of tumor cells with normal host elements, but the underlying mechanisms are incompletely understood. Here, we show that milk fat globule EGF-8 (MFG-E8), a secreted protein expressed at high levels in the vertical growth phase of melanoma, promotes disease progression through coordinated αvβ3 integrin signaling in the tumor microenvironment. In a murine model of melanoma, MFG-E8 enhanced tumorigenicity and metastatic capacity through Akt-dependent and Twist-dependent pathways. MFG-E8 augmented melanoma cell resistance to apoptosis, triggered an epithelial-to-mesenchymal transition (EMT), and stimulated invasion and immune suppression. In human melanoma cells, MFG-E8 knockdown attenuated Akt and Twist signaling and thereby compromised tumor cell survival, EMT, and invasive ability. MFG-E8–deficient human melanoma cells also showed increased sensitivity to small molecule inhibitors of insulin-like growth factor I receptor and c-Met. Together, these findings delineate pleiotropic roles for MFG-E8 in the tumor microenvironment and raise the possibility that systemic MFG-E8 blockade might prove therapeutic for melanoma patients. [Cancer Res 2008;68(21):8889–98]
Data from Tubulin-Targeted Drug Action: Functional Significance of Class II and Class IVb β-Tubulin in Vinca Alkaloid Sensitivity
Authors: Gan Pei Pei , Kavallaris Maria
Published: March 2023

Abstract
Aberrant expression of β-tubulin isotypes is frequently described in tumor tissues and tubulin-binding agent (TBA)–resistant cell lines. There is limited understanding of the role of specific β-tubulin isotypes in cellular sensitivity to TBAs, and to gain insights into the functional role of βII- and βIVb-tubulin, we examined these isotypes in lung cancer cell lines NCI-H460 (H460) and Calu-6. Drug-treated clonogenic assays revealed that small interfering RNA–mediated knockdown of either βII- or βIVb-tubulin hypersensitized the lung cancer cell lines to Vinca alkaloids, with the effects more pronounced following βIVb-tubulin knockdown. In contrast, there was no change in paclitaxel sensitivity following knockdown of either isotype. Cell cycle analysis revealed a greater propensity for the βII- and βIVb-tubulin knockdown cells to undergo G2-M cell cycle block following 5 nmol/L vincristine treatment, with the βIVb knockdown cells being more sensitive than the βII-tubulin knockdown cells compared with control. In contrast to βII-tubulin knockdown, βIVb-tubulin knockdown cells showed a significant increase in the sub-G1 population (cell death) following treatment with both 5 and 40 nmol/L of vincristine compared with controls. Importantly, βIVb-tubulin knockdown in H460 cells caused a significant dose-dependent increase in Annexin V staining in response to vincristine but not paclitaxel. Therefore, increased sensitivity to induction of apoptosis is one mechanism underlying the Vinca alkaloid hypersensitivity. This study provides direct evidence that βII- or βIVb-tubulins have functionally distinct roles and expression of these isotypes may serve as strong predictors of Vinca alkaloid response and resistance. [Cancer Res 2008;68(23):9817–24]
Data from Mechanism of Regulation and Suppression of Melanoma Invasiveness by Novel Retinoic Acid Receptor-γ Target Gene Carbohydrate Sulfotransferase 10
Authors: Zhao Xiansi , Graves Carole , Ames Sarah J. , Fisher David E. , Spanjaard Remco A.
Published: March 2023

Abstract
Retinoic acid (RA) induces growth arrest and differentiation of S91 murine melanoma cells and serves as a valuable model for this disease. RA acts through activation of RA receptors (RAR), which are members of the nuclear receptor superfamily of ligand-inducible transcription factors. Interestingly, differentiation is mediated by RARγ, but not by RARα or RARβ, suggesting that RARγ possesses unique and uncharacterized molecular properties. To address this question, DNA microarrays in combination with RAR isoform-specific agonists were employed to identify novel RARγ target genes that may play a role in this process. Here, we identified and validated carbohydrate sulfotransferase 10 (CHST10) as a novel RARγ target gene in S91 cells. The RARγ-inducible CHST10 promoter was obtained, and two atypical, independently functioning RA response elements were identified in a 425 bp region. Surprisingly, this fragment is bound by RARγ, but not by RARα or RARβ, thus providing a mechanism for the observed RARγ-specific regulation. CHST10 is a sulfotransferase that forms HNK-1 glycan on neural cell adhesion proteins and glycolipids, and HNK-1 is thought to modulate cell adhesion and possibly metastasis. We show that CHST10 is also regulated by RARγ in a significant subset of human melanoma cells, and three-dimensional cell culture migration assays suggest that CHST10 functions as a suppressor of invasiveness, but not proliferation, in these cells. Induction of CHST10 by RARγ-activating retinoids may present a novel therapeutic strategy to inhibit invasiveness in a subset of melanoma patients. [Cancer Res 2009;69(12):5218–25]
Data from Paclitaxel Directly Binds to Bcl-2 and Functionally Mimics Activity of Nur77
Authors: Ferlini Cristiano , Cicchillitti Lucia , Raspaglio Giuseppina , Bartollino Silvia , Cimitan Samanta , Bertucci Carlo , Mozzetti Simona , Gallo Daniela , Persico Marco , Fattorusso Caterina , Campiani Giuseppe , Scambia Giovanni
Published: March 2023

Abstract
We reported previously that Bcl-2 is paradoxically down-regulated in paclitaxel-resistant cancer cells. We reveal here that paclitaxel directly targets Bcl-2 in the loop domain, thereby facilitating the initiation of apoptosis. Molecular modeling revealed an extraordinary similarity between the paclitaxel binding sites in Bcl-2 and β-tubulin, leading us to speculate that paclitaxel could be mimetic of an endogenous peptide ligand, which binds both proteins. We tested the hypothesis that paclitaxel mimics Nur77, which, like paclitaxel, changes the function of Bcl-2. This premise was confirmed by Nur77 interacting with both paclitaxel targets (Bcl-2 and β-tubulin) and a peptide sequence mimicking the Nur77 structural region, thus reproducing the paclitaxel-like effects of tubulin polymerization and opening the permeability transition pore channel in mitochondria. This discovery could help in the development of novel anticancer agents with nontaxane skeleton as well as in identifying the clinical subsets responsive to paclitaxel-based therapy. [Cancer Res 2009;69(17):6906–14]
Data from Cell Survival under Stress Is Enhanced by a Mitochondrial ATP-Binding Cassette Transporter That Regulates Hemoproteins
Authors: Lynch John , Fukuda Yu , Krishnamurthy Partha , Du Guoqing , Schuetz John D.
Published: March 2023

Abstract
The ATP-binding cassette (ABC) transporter ABCB6 localizes to the mitochondria, where it imports porphyrins and up-regulates de novo porphyrin synthesis. If ABCB6 also increases the intracellular heme concentration, it may broadly affect the regulation and physiology of cellular hemoproteins. We tested whether the ability of ABCB6 to accelerate de novo porphyrin biosynthesis alters mitochondrial and extramitochondrial heme levels. ABCB6 overexpression increased the quantity of cytosolic heme but did not affect mitochondrial heme levels. We then tested whether the increased extramitochondrial heme would increase the concentration and/or activity of cellular hemoproteins (hemoglobin, catalase, and cytochrome c oxidase). ABCB6 overexpression increased the activity and quantity of hemoproteins found in several subcellular compartments, and reduction of ABCB6 function (by small interfering RNA or knockout) reversed these findings. In complementary studies, suppression of ABCB6 expression sensitized cells to stress induced by peroxide and cyanide, whereas overexpression of ABCB6 protected against both stressors. Our findings show that the ability of ABCB6 to increase cytosolic heme levels produces phenotypic changes in hemoproteins that protect cells from certain stresses. Collectively, these findings have implications for the health and survival of both normal and abnormal cells, which rely on heme for multiple cellular processes. [Cancer Res 2009;69(13):5560–7]
Data from Pancreatic Cancer and Precursor Pancreatic Intraepithelial Neoplasia Lesions Are Devoid of Primary Cilia
Authors: Seeley E. Scott , Carrière Catherine , Goetze Tobias , Longnecker Daniel S. , Korc Murray
Published: March 2023

Abstract
Primary cilia have been proposed to participate in the modulation of growth factor signaling pathways. In this study, we determined that ciliogenesis is suppressed in both pancreatic cancer cells and pancreatic intraepithelial neoplasia (PanIN) lesions in human pancreatic ductal adenocarcinoma (PDAC). Primary cilia were absent in these cells even when not actively proliferating. Cilia were also absent from mouse PanIN cells in three different mouse models of PDAC driven by an endogenous oncogenic Kras allele. Inhibition of Kras effector pathways restored ciliogenesis in a mouse pancreatic cancer cell line, raising the possibility that ciliogenesis may be actively repressed by oncogenic Kras. By contrast, normal duct, islet, and centroacinar cells retained primary cilia in both human and mouse pancreata. Thus, arrested ciliogenesis is a cardinal feature of PDAC and its precursor PanIN lesions, does not require ongoing proliferation, and could potentially be targeted pharmacologically. [Cancer Res 2009;69(2):422–30]
Data from Mesenchymal Stem Cell Delivery of TRAIL Can Eliminate Metastatic Cancer
Authors: Loebinger Michael R. , Eddaoudi Ayad , Davies Derek , Janes Sam M.
Published: March 2023

Abstract
Cancer is a leading cause of mortality throughout the world and new treatments are urgently needed. Recent studies suggest that bone marrow–derived mesenchymal stem cells (MSC) home to and incorporate within tumor tissue. We hypothesized that MSCs engineered to produce and deliver tumor necrosis factor–related apoptosis-inducing ligand (TRAIL), a transmembrane protein that causes selective apoptosis of tumor cells, would home to and kill cancer cells in a lung metastatic cancer model. Human MSCs were transduced with TRAIL and the IRES-eGFP reporter gene under the control of a tetracycline promoter using a lentiviral vector. Transduced and activated MSCs caused lung (A549), breast (MDAMB231), squamous (H357), and cervical (Hela) cancer cell apoptosis and death in coculture experiments. Subcutaneous xenograft experiments confirmed that directly delivered TRAIL-expressing MSCs were able to significantly reduce tumor growth [0.12 cm3 (0.04-0.21) versus 0.66 cm3 (0.21-1.11); P < 0.001]. We then found, using a pulmonary metastasis model, systemically delivered MSCs localized to lung metastases and the controlled local delivery of TRAIL completely cleared the metastatic disease in 38% of mice compared with 0% of controls (P < 0.05). This is the first study to show a significant reduction in metastatic tumor burden with frequent eradication of metastases using inducible TRAIL-expressing MSCs. This has a wide potential therapeutic role, which includes the treatment of both primary tumors and their metastases, possibly as an adjuvant therapy in clearing micrometastatic disease following primary tumor resection. [Cancer Res 2009;69(10):4134–42]
Data from p34SEI-1 Inhibits Apoptosis through the Stabilization of the X-Linked Inhibitor of Apoptosis Protein: p34SEI-1 as a Novel Target for Anti–Breast Cancer Strategies
Authors: Hong Seung-Woo , Kim Chang-Jae , Park Won-Sang , Shin Jae-Sik , Lee Soon-Duck , Ko Seong-Gyu , Jung Sam-Il , Park In-Chul , An Sung-Kwan , Lee Won-Keun , Lee Wang-Jae , Jin Dong-Hoon , Lee Myeong-Sok
Published: March 2023

Abstract
The p34SEI-1 protein exerts oncogenic effects via regulation of the cell cycle, which occurs through a direct interaction with cyclin-dependent kinase 4. Such regulation can increase the survival of various types of tumor cells. Here, we show that the antiapoptotic function of p34SEI-1 increases tumor cell survival by protecting the X-linked inhibitor of apoptosis protein (XIAP) from degradation. Our findings show that p34SEI-1 inhibits apoptosis. This antiapoptotic effect was eliminated by the suppression of p34SEI-1 expression. We also determined that direct binding of p34SEI-1 to the BIR2 domain prevents ubiquitination of XIAP. Interestingly, p34SEI-1 expression is absent or weak in normal tissues but is strongly expressed in tissues obtained from patients with breast cancer. Furthermore, the expression levels of p34SEI-1 and XIAP seem to be coordinated in human breast cancer cell lines and tumor tissues. Thus, our findings reveal that p34SEI-1 uses a novel apoptosis-inhibiting mechanism to stabilize XIAP. [Cancer Res 2009;69(3):741–6]
Data from In vivo Off-Resonance Saturation Magnetic Resonance Imaging of αvβ3-Targeted Superparamagnetic Nanoparticles
Authors: Khemtong Chalermchai , Kessinger Chase W. , Ren Jimin , Bey Erik A. , Yang Su-Geun , Guthi Jagadeesh Setti , Boothman David A. , Sherry A. Dean , Gao Jinming
Published: March 2023

Abstract
Magnetic resonance imaging is a powerful clinical imaging technique that allows for noninvasive tomographic visualization of anatomic structures with high spatial resolution and soft tissue contrast. However, its application in molecular imaging of cancer has been limited by the lack of sensitivity and detection accuracy in depicting the biochemical expression of these diseases. Here, we combine an ultrasensitive design of superparamagnetic polymeric micelles (SPPM) and an off-resonance saturation (ORS) method to enhance the imaging efficacy of tumor biomarkers in vivo. SPPM nanoparticles encoded with cyclic(RGDfK) were able to target the αvβ3-expressing microvasculature in A549 non–small cell lung tumor xenografts in mice. ORS greatly improved tumor detection accuracy over the conventional T2*-weighted method by its ability to turn “ON” the contrast of SPPM. This combination of ORS imaging with a tumor vasculature–targeted, ultrasensitive SPPM design offers new opportunities in molecular imaging of cancer. [Cancer Res 2009;69(4):1651–8]
Data from TrkBT1 Induces Liver Metastasis of Pancreatic Cancer Cells by Sequestering Rho GDP Dissociation Inhibitor and Promoting RhoA Activation
Authors: Li Zhongkui , Chang Zhe , Chiao Lucia J. , Kang Ya'an , Xia Qianghua , Zhu Cihui , Fleming Jason B. , Evans Douglas B. , Chiao Paul J.
Published: March 2023

Abstract
Many genetic and molecular alterations, such as K-ras mutation and NF-κB activation, have been identified in pancreatic cancer. However, the mechanisms by which pancreatic cancer metastasizes still remain to be determined. Although we previously showed that the tropomyosin-related kinase B (TrkB) was significantly correlated with the development of liver metastasis, its function in pancreatic cancer metastasis remained unresolved. In the present study, we showed that overexpressed TrkB is an alternatively spliced transcript variant of TrkB (TrkBT1) with a unique COOH-terminal 12–amino acid sequence and is mainly localized in the cytoplasm. Our results showed that overexpression of Flag-tagged TrkBT1 but not a Flag-tagged TrkBT1 COOH-terminal deletion mutant (Flag-TrkBT1ΔC) in nonmetastatic pancreatic cancer cells enhanced cell proliferation, promoted formation of colonies in soft agar, stimulated tumor cell invasion, and induced liver metastasis in an orthotopic xenograft mouse model of pancreatic cancer. TrkBT1 interacted with Rho GDP dissociation inhibitor (GDI) in vivo, but Flag-TrkBT1ΔC did not. Furthermore, overexpression of Flag-TrkBT1 and knockdown of RhoGDI expression by RhoGDI short hairpin RNAs promoted RhoA activation, but Flag-TrkBT1ΔC overexpression did not. Therefore, our results showed that TrkBT1 overexpression induces liver metastasis of pancreatic cancer and uncovered a unique signaling mechanism by which TrkBT1 sequesters GDI and activates RhoA signaling. [Cancer Res 2009;69(19):7851–9]