bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from The Skin Cancer Chemotherapeutic Agent Ingenol-3-Angelate (PEP005) Is a Substrate for the Epidermal Multidrug Transporter (ABCB1) and Targets Tumor Vasculature
Authors: Li Luowei , Shukla Suneet , Lee Andrew , Garfield Susan H. , Maloney David J. , Ambudkar Suresh V. , Yuspa Stuart H.
Published: March 2023

Abstract
Ingenol-3-angelate (Ing3A), extracted from Euphorbia peplus, is currently in clinical trials for eradicating basal cell carcinoma, actinic keratosis, and squamous cell carcinoma (SCC) in situ by topical application. Although structurally related to phorbol esters and a protein kinase C activator, topical Ing3A, but not phorbol 12-myristate 13-acetate (PMA), inhibited the growth of subcutaneous tumors derived from PAM212 (mouse SCC) and B16 (mouse melanoma). Ing3A and PMA both induced acute neutrophilic inflammation on mouse skin, but only Ing3A caused subcutaneous hemorrhage and vascular damage. Both Ing3A and PMA activated extracellular signal-regulated kinase 1/2 (ERK1/2) in epidermis, but Ing3A also activated ERK1/2 in skin dermal fibroblasts and endothelial cells. Pretreatment with topical cyclosporin A (CsA), verapamil, or XR9576, modulators of P-glycoprotein (P-gp), prevented Ing3A-induced hemorrhage but not neutrophil infiltration. CsA also impaired the anticancer activity of Ing3A, whereas the anti-inflammatory dexamethasone did not. Ing3A, but not PMA, blocked photoaffinity labeling of human P-gp with [125I]iodoaryazidoprazosin and inhibited P-gp–mediated drug resistance to HCT-15 cells. The intracellular levels of Ing3A were significantly lower in P-gp–expressing cells, and treatment with XR9576 increased the levels to those of cells that do not express P-gp, showing that Ing3A binds to and is transported by P-gp. Taken together, our results suggest that P-gp–mediated absorptive transport, dermal penetration, and vascular damage contribute to the anticancer activity of Ing3A in vivo. Cancer Res; 70(11); 4509–19. ©2010 AACR.
Data from Small-Molecule Inhibitors of Phosphatidylinositol 3-Kinase/Akt Signaling Inhibit Wnt/β-Catenin Pathway Cross-Talk and Suppress Medulloblastoma Growth
Authors: Baryawno Ninib , Sveinbjörnsson Baldur , Eksborg Staffan , Chen Ching-Shih , Kogner Per , Johnsen John Inge
Published: March 2023

Abstract
Activation of the β-catenin and receptor kinase pathways occurs often in medulloblastoma, the most common pediatric malignant brain tumor. In this study, we show that molecular cross-talk between the β-catenin and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways is crucial to sustain medulloblastoma pathophysiology. Constitutive activation of phosphoinositide-dependent protein kinase 1 (PDK1), Akt, and glycogen synthase kinase 3β (GSK-3β) was detected by immunohistochemistry in all primary medulloblastomas examined (n = 41). Small-molecule inhibitors targeting the PI3K/Akt signaling pathway affected β-catenin signaling by inhibition of GSK-3β activity, resulting in cytoplasmic retention of β-catenin and reduced expression of its target genes cyclin D1 and c-Myc. The PDK1 inhibitor OSU03012 induced mitochondrial-dependent apoptosis of medulloblastoma cells and enhanced the cytotoxic effects of chemotherapeutic drugs in a synergistic or additive manner. In vivo, OSU03012 inhibited the growth of established medulloblastoma xenograft tumors in a dose-dependent manner and augmented the antitumor effects of mammalian target of rapamycin inhibitor CCI-779. These findings demonstrate the importance of cross-talk between the PI3K/Akt and β-catenin pathways in medulloblastoma and rationalize the PI3K/Akt signaling pathway as a therapeutic target in treatment of this disease. Cancer Res; 70(1); 266–76
Data from Diagnosing Cervical Cancer and High-Grade Precursors by HPV16 Transcription Patterns
Authors: Schmitt Markus , Dalstein Véronique , Waterboer Tim , Clavel Christine , Gissmann Lutz , Pawlita Michael
Published: March 2023

Abstract
Infections with high-risk human papillomaviruses (HPV), mainly HPV type 16, can cause malignant transformation of the human cervical epithelium and the development of cervical cancer (CxCa). A rapid and precise diagnosis of the precancerous lesions by conventional cytology or HPV DNA tests remains difficult and often leads to overtreatment. We quantitatively analyzed the HPV16 transcriptome of 80 HPV16 DNA-positive cervical scrapes classified as mild cytologic grade, including no intraepithelial lesion or malignancy (NIL/M; normal, n = 25) and low-grade squamous intraepithelial lesion (LSIL; n = 24), and severe cytologic grade, including high-grade squamous intraepithelial lesion (HSIL; n = 24) and CxCa (n = 7), with novel nucleic acid sequence-based amplification–Luminex assays. In severe lesions, HPV16 E6*II and E1C encoding transcripts were strongly upregulated, whereas spliced E1^E4 and L1 encoding transcripts were markedly downregulated. Using a combination of the four marker transcripts, 100% of CxCa and 67% of HSIL cases were correctly identified as severe, and 74% of LSIL and 92% of NIL/M samples as mild cytologic grade. Compared with a commercially available HPV E6/E7 mRNA assay, the specificity of the marker combination for discriminating severe and mild cytologic lesions increased from 23% to 83%. In conclusion, we identified a novel HPV16 RNA pattern for grading of cervical lesions with a potentially high diagnostic value for the primary screening of CxCa precursors and the triage of cervical lesions. Cancer Res; 70(1); 249–56
Data from Apolipoprotein E/C1 Locus Variants Modify Renal Cell Carcinoma Risk
Authors: Moore Lee E. , Brennan Paul , Karami Sara , Menashe Idan , Berndt Sonja I. , Dong Linda M. , Meisner Allison , Yeager Meredith , Chanock Stephen , Colt Joanne , Schwartz Kendra , Davis Faith , Zaridze David , Mattveev Vsevolod , Janout Vladimir , Kollarova Hellena , Bencko Vladimir , Navratilova Marie , Szeszenia-Dabrowska Neonilia , Mates Dana , Holcatova Ivana , Boffetta Paolo , Chow Wong-Ho , Rosenberg Philip S. , Rothman Nathaniel
Published: March 2023

Abstract
Lipid peroxidation is considered a unifying mechanistic pathway through which known risk factors induce renal cell carcinoma (RCC). We hypothesized that genes selected a priori for their role in lipid peroxidation would modify cancer risk. We genotyped 635 single nucleotide polymorphisms (SNP) in 38candidate genes in 777 Caucasian RCC cases and 1,035 controls enrolled in a large European case-control study. Top candidate SNPs were confirmed among 718 Caucasian cases and 615 controls in a second study in the United States. Two of the three SNPs (rs8106822 and rs405509) that replicated in the U.S. study were within a regulatory region of the APOE promoter. The OR for rs8106822 A>G variant was 1.22AG and 1.41GG (Ptrend = 0.01) in the European study, 1.05AG and 1.51GG (Ptrend = 0.03) in the U.S. study, and 1.15AG and 1.44GG (Ptrend = 0.001) among 1,485 cases and 1,639 controls combined. The rs405509 G>T variant was associated with risk in the European (OR, 0.87TG; OR, 0.71TT; Ptrend = 0.02), the U.S. (OR, 0.68TG; OR, 0.71TT; Ptrend = 0.02), and both studies combined (ORTG, 0.79; ORTT, 0.71; Ptrend = 0.001), as was the G-G haplotype (r2 = 0.64; P= 4.7 × 10−4). This association is biologically plausible as SNP rs405509 was shown to modify protein binding and transcriptional activity of the APOE protein in vitro and is in linkage disequilibrium with key known variants defining the e2, e3, and e4 alleles that modify risk of atherosclerosis, Alzheimer's disease risk, and progression to AIDS. In two large case-control studies, our findings further define a functional region of interest at the APOE locus that increases RCC susceptibility. [Cancer Res 2009;69(20):8001–8]
Data from Intrinsic Gene Expression Profiles of Gliomas Are a Better Predictor of Survival than Histology
Authors: Gravendeel Lonneke A.M. , Kouwenhoven Mathilde C.M. , Gevaert Olivier , de Rooi Johan J. , Stubbs Andrew P. , Duijm J. Elza , Daemen Anneleen , Bleeker Fonnet E. , Bralten Linda B.C. , Kloosterhof Nanne K. , De Moor Bart , Eilers Paul H.C. , van der Spek Peter J. , Kros Johan M. , Sillevis Smitt Peter A.E. , van den Bent Martin J. , French Pim J.
Published: March 2023

Abstract
Gliomas are the most common primary brain tumors with heterogeneous morphology and variable prognosis. Treatment decisions in patients rely mainly on histologic classification and clinical parameters. However, differences between histologic subclasses and grades are subtle, and classifying gliomas is subject to a large interobserver variability. To improve current classification standards, we have performed gene expression profiling on a large cohort of glioma samples of all histologic subtypes and grades. We identified seven distinct molecular subgroups that correlate with survival. These include two favorable prognostic subgroups (median survival, >4.7 years), two with intermediate prognosis (median survival, 1–4 years), two with poor prognosis (median survival, <1 year), and one control group. The intrinsic molecular subtypes of glioma are different from histologic subgroups and correlate better to patient survival. The prognostic value of molecular subgroups was validated on five independent sample cohorts (The Cancer Genome Atlas, Repository for Molecular Brain Neoplasia Data, GSE12907, GSE4271, and Li and colleagues). The power of intrinsic subtyping is shown by its ability to identify a subset of prognostically favorable tumors within an external data set that contains only histologically confirmed glioblastomas (GBM). Specific genetic changes (epidermal growth factor receptor amplification, IDH1 mutation, and 1p/19q loss of heterozygosity) segregate in distinct molecular subgroups. We identified a subgroup with molecular features associated with secondary GBM, suggesting that different genetic changes drive gene expression profiles. Finally, we assessed response to treatment in molecular subgroups. Our data provide compelling evidence that expression profiling is a more accurate and objective method to classify gliomas than histologic classification. Molecular classification therefore may aid diagnosis and can guide clinical decision making. [Cancer Res 2009;69(23):9065–72]
Data from hnRNP A2 Regulates Alternative mRNA Splicing of TP53INP2 to Control Invasive Cell Migration
Authors: Moran-Jones Kim , Grindlay Joan , Jones Marc , Smith Ross , Norman Jim C.
Published: March 2023

Abstract
Largely owing to widespread deployment of microarray analysis, many of the transcriptional events associated with invasive cell migration are becoming clear. However, the transcriptional drives to invasive migration are likely modified by alternative splicing of pre-mRNAs to produce functionally distinct patterns of protein expression. Heterogenous nuclear ribonucleoprotein (hnRNP A2) is a known regulator of alternative splicing that is upregulated in a number of invasive cancer types. Here, we report that although siRNA of hnRNP A2 had little influence on the ability of cells to migrate on plastic surfaces, the splicing regulator was clearly required for cells to move effectively on three-dimensional matrices and to invade into plugs of extracellular matrix proteins. We used exon-tiling microarrays to determine that hnRNP A2 controlled approximately six individual splicing events in a three-dimensional matrix-dependent fashion, one of which influenced invasive migration. Here, we show that alternative splicing of an exon in the 5′ untranslated region of a gene termed TP53INP2 is a key event downstream of hnRNP A2 that is necessary for cells to invade the extracellular matrix. Furthermore, we report that the consequences of altered TP53INP2 splicing on invasion are likely mediated via alterations in Golgi complex integrity during migration on three-dimensional matrices. [Cancer Res 2009;69(24):9219–27]
Data from AML1/ETO Proteins Control POU4F1/BRN3A Expression and Function in t(8;21) Acute Myeloid Leukemia
Authors: Dunne Jenny , Gascoyne Duncan M. , Lister T. Andrew , Brady Hugh J.M. , Heidenreich Olaf , Young Bryan D.
Published: March 2023

Abstract
A variety of genetic lesions, including chromosomal translocations, internal tandem duplications, and mutations, have been described in acute myeloid leukemia (AML). Expression profiling has shown that chromosomal translocations, in particular, are associated with distinctive patterns of gene expression. AML exhibiting the translocation t(8;21), which fuses the AML1 and ETO genes, has such a characteristic expression profile. One gene whose expression is highly correlated with the presence of the AML1/ETO fusion is POU4F1, which encodes the POU homeodomain transcription factor BRN3A. Here we show using specific siRNA in t(8;21) cells and overexpression studies in progenitor cells that AML1/ETO promotes expression of POU4F1/BRN3A. This effect requires DNA-binding function of AML1/ETO, and accordingly, AML1/ETO is bound to the POU4F1 locus in t(8;21) cells. Functionally, whereas overexpression of Brn3a in murine hematopoietic progenitor cells induces terminal myeloid differentiation, coexpression of AML1/ETO or AML1/ETO9a blocks this effect. Furthermore, Brn3a reduction by shRNA impairs AML1/ETO-induced immortalization of murine progenitors. In summary, we identify POU4F1/BRN3A as a novel potential upregulated AML1/ETO target gene whose dramatically high expression may cooperate with AML1/ETO in t(8;21) cells. Cancer Res; 70(10); 3985–95. ©2010 AACR.
Data from Identification of Compounds Selectively Killing Multidrug-Resistant Cancer Cells
Authors: Türk Dóra , Hall Matthew D. , Chu Benjamin F. , Ludwig Joseph A. , Fales Henry M. , Gottesman Michael M. , Szakács Gergely
Published: March 2023

Abstract
There is a great need for the development of novel chemotherapeutic agents that overcome the emergence of multidrug resistance (MDR) in cancer. We catalogued the National Cancer Institute's DTP drug repository in search of compounds showing increased toxicity in MDR cells. By comparing the sensitivity of parental cell lines with MDR derivatives, we identified 22 compounds possessing MDR-selective activity. Analysis of structural congeners led to the identification of 15 additional drugs showing increased toxicity in Pgp-expressing cells. Analysis of MDR-selective compounds led to the formulation of structure activity relationships and pharmacophore models. This data mining coupled with experimental data points to a possible mechanism of action linked to metal chelation. Taken together, the discovery of the MDR-selective compound set shows the robustness of the developing field of MDR-targeting therapy as a new strategy for resolving Pgp-mediated MDR. [Cancer Res 2009;69(21):8293–301]
Data from Nrdp1-Mediated Regulation of ErbB3 Expression by the Androgen Receptor in Androgen-Dependent but not Castrate-Resistant Prostate Cancer Cells
Authors: Chen Liqun , Siddiqui Salma , Bose Swagata , Mooso Benjamin , Asuncion Alfredo , Bedolla Roble G. , Vinall Ruth , Tepper Clifford G. , Gandour-Edwards Regina , Shi XuBao , Lu Xiao-Hua , Siddiqui Javed , Chinnaiyan Arul M. , Mehra Rohit , deVere White Ralph W. , Carraway Kermit L. , Ghosh Paramita M.
Published: March 2023

Abstract
Patients with advanced prostate cancer (PCa) are initially susceptible to androgen withdrawal (AW), but ultimately develop resistance to this therapy (castration-resistant PCa, CRPC). Here, we show that AW can promote CRPC development by increasing the levels of the receptor tyrosine kinase ErbB3 in androgen-dependent PCa, resulting in AW-resistant cell cycle progression and increased androgen receptor (AR) transcriptional activity. CRPC cell lines and human PCa tissue overexpressed ErbB3, whereas downregulation of ErbB3 prevented CRPC cell growth. Investigation of the mechanism by which AW augments ErbB3, using normal prostate-derived pRNS-1-1 cells, and androgen-dependent PCa lines LNCaP, PC346C, and CWR22 mouse xenografts, revealed that the AR suppresses ErbB3 protein levels, whereas AW relieves this suppression, showing for the first time the negative regulation of ErbB3 by AR. We show that AR activation promotes ErbB3 degradation in androgen-dependent cells, and that this effect is mediated by AR-dependent transcriptional upregulation of neuregulin receptor degradation protein-1 (Nrdp1), an E3 ubiquitin ligase that targets ErbB3 for degradation but whose role in PCa has not been previously examined. Therefore, AW decreases Nrdp1 expression, promoting ErbB3 protein accumulation, and leading to AR-independent proliferation. However, in CRPC sublines of LNCaP and CWR22, which strongly overexpress the AR, ErbB3 levels remain elevated due to constitutive suppression of Nrdp1, which prevents AR regulation of Nrdp1. Our observations point to a model of CRPC development in which progression of PCa to castration resistance is associated with the inability of AR to transcriptionally regulate Nrdp1, and predict that inhibition of ErbB3 during AW may impair CRPC development. Cancer Res; 70(14); 5994–6003. ©2010 AACR.
Data from PTEN Loss Compromises Homologous Recombination Repair in Astrocytes: Implications for Glioblastoma Therapy with Temozolomide or Poly(ADP-Ribose) Polymerase Inhibitors
Authors: McEllin Brian , Camacho Cristel V. , Mukherjee Bipasha , Hahm Brandon , Tomimatsu Nozomi , Bachoo Robert M. , Burma Sandeep
Published: March 2023

Abstract
Glioblastomas (GBM) are lethal brain tumors that are highly resistant to therapy. The only meaningful improvement in therapeutic response came from use of the SN1-type alkylating agent temozolomide in combination with ionizing radiation. However, no genetic markers that might predict a better response to DNA alkylating agents have been identified in GBMs, except for loss of O6-methylguanine-DNA methyltransferase via promoter methylation. In this study, using genetically defined primary murine astrocytes as well as human glioma lines, we show that loss of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) confers sensitivity to N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), a functional analogue of temozolomide. We find that MNNG induces replication-associated DNA double-strand breaks (DSB), which are inefficiently repaired in PTEN-deficient astrocytes and trigger apoptosis. Mechanistically, this is because PTEN-null astrocytes are compromised in homologous recombination (HR), which is important for the repair of replication-associated DSBs. Our results suggest that reduced levels of Rad51 paralogs in PTEN-null astrocytes might underlie the HR deficiency of these cells. Importantly, the HR deficiency of PTEN-null cells renders them sensitive to the poly(ADP-ribose) polymerase (PARP) inhibitor ABT-888 due to synthetic lethality. In sum, our results tentatively suggest that patients with PTEN-null GBMs (about 36%) may especially benefit from treatment with DNA alkylating agents such as temozolomide. Significantly, our results also provide a rational basis for treating the subgroup of patients who are PTEN deficient with PARP inhibitors in addition to the current treatment regimen of radiation and temozolomide. Cancer Res; 70(13); 5457–64. ©2010 AACR.
Data from CDX2 Regulates Multidrug Resistance 1 Gene Expression in Malignant Intestinal Epithelium
Authors: Takakura Yuji , Hinoi Takao , Oue Naohide , Sasada Tatsunari , Kawaguchi Yasuo , Okajima Masazumi , Akyol Aytekin , Fearon Eric R. , Yasui Wataru , Ohdan Hideki
Published: March 2023

Abstract
The caudal-related homeobox transcription factor CDX2 has a key role in intestinal development and differentiation. CDX2 heterozygous mutant mice develop colonic polyps, and loss of CDX2 expression is seen in a subset of colon carcinomas in humans. Ectopic CDX2 expression in the stomach of transgenic mice promotes intestinal metaplasia, and CDX2 expression is frequently detected in intestinal metaplasia in the stomach and esophagus. We sought to define CDX2-regulated genes to enhance knowledge of CDX2 function. HT-29 colorectal cancer cells have minimal endogenous CDX2 expression, and HT-29 cells with ectopic CDX2 expression were generated. Microarray-based gene expression studies revealed that the Multidrug Resistance 1 (MDR1/P-glycoprotein/ABCB1) gene was activated by CDX2. Evidence that the MDR1 gene was a direct transcriptional target of CDX2 was obtained, including analyses with MDR1 reporter gene constructs and chromatin immunoprecipitation assays. RNA interference–mediated inhibition of CDX2 decreased endogenous MDR1 expression. In various colorectal cancer cell lines and human tissues, endogenous MDR1 expression was well correlated to CDX2 expression. Overexpression of CDX2 in HT-29 cells revealed increased resistance to the known substrate of MDR1, vincristine and paclitaxel, which was reversed by an MDR1 inhibitor, verapamil. These data indicate that CDX2 directly regulates MDR1 gene expression through binding to elements in the promoter region. Thus, CDX2 is probably important for basal expression of MDR1, regulating drug excretion and absorption in the lower gastrointestinal tract, as well as for multidrug resistance to chemotherapy reagent in CDX2-positive gastrointestinal cancers. Cancer Res; 70(17); 6767–78. ©2010 AACR.
Data from Mechanism by Which Mcl-1 Regulates Cancer-Specific Apoptosis Triggered by mda-7/IL-24, an IL-10–Related Cytokine
Authors: Dash Rupesh , Richards Joanna E. , Su Zhao-zhong , Bhutia Sujit K. , Azab Belal , Rahmani Mohamed , Dasmahapatra Girija , Yacoub Adly , Dent Paul , Dmitriev Igor P. , Curiel David T. , Grant Steven , Pellecchia Maurizio , Reed John C. , Sarkar Devanand , Fisher Paul B.
Published: March 2023

Abstract
Melanoma differentiation-associated gene-7/interleukin-24 (mda-7/IL-24), a cytokine belonging to the IL-10 family, selectively induces apoptosis in cancer cells without harming normal cells by promoting an endoplasmic reticulum (ER) stress response. The precise molecular mechanism by which the ER stress response culminates in cell death requires further clarification. The present study shows that in prostate carcinoma cells, the mda-7/IL-24–induced ER stress response causes apoptosis by translational inhibition of the antiapoptotic protein myeloid cell leukemia-1 (Mcl-1). Forced expression of Mcl-1 blocked mda-7/IL-24 lethality, whereas RNA interference or gene knockout of Mcl-1 markedly sensitized transformed cells to mda-7/IL-24. Mcl-1 downregulation by mda-7/IL-24 relieved its association with the proapoptotic protein Bak, causing oligomerization of Bak and leading to cell death. These observations show the profound role of the Bcl-2 protein family member Mcl-1 in regulating cancer-specific apoptosis induced by this cytokine. Thus, our studies provide further insights into the molecular mechanism of ER stress–induced cancer-selective apoptosis by mda-7/IL-24. As Mcl-1 is overexpressed in the majority of prostate cancers, mda-7/IL-24 might provide an effective therapeutic for this disease. Cancer Res; 70(12); 5034–45. ©2010 AACR.
Data from Novel Dyskerin-Mediated Mechanism of p53 Inactivation through Defective mRNA Translation
Authors: Montanaro Lorenzo , Calienni Maria , Bertoni Sara , Rocchi Laura , Sansone Pasquale , Storci Gianluca , Santini Donatella , Ceccarelli Claudio , Taffurelli Mario , Carnicelli Domenica , Brigotti Maurizio , Bonafè Massimiliano , Treré Davide , Derenzini Massimo
Published: March 2023

Abstract
In up to 60% of human cancers, p53 gene mutations are responsible for direct inactivation of the tumor suppressor function of p53. Alternative mechanisms of p53 inactivation described thus far mainly affect its posttranslational regulation. In X-linked dyskeratosis congenita, a multisystemic syndrome characterized by increased cancer susceptibility, mutations of the DKC1 gene encoding dyskerin cause a selective defect in the translation of a subgroup of internal ribosome entry site (IRES)–containing cellular mRNAs. In this study, we show that impairment of dyskerin function can cause p53 inactivation due to a defect in p53 mRNA translation. siRNA-mediated reduction of dyskerin levels caused a decrease of p53 mRNA translation, protein levels, and functional activity, both in human breast cancer cells and in primary mammary epithelial progenitor cells. These effects seemed to be independent of the known role of dyskerin in telomerase function, and they were associated with a specific impairment of translation initiation mediated by IRES elements present in p53 mRNA. In a series of human primary breast cancers retaining wild-type p53, we found that low levels of dyskerin expression were associated with reduced expression of p53-positive target genes. Our findings suggest that a dyskerin-mediated mechanism of p53 inactivation may occur in a subset of human tumors. Cancer Res; 70(11); 4767–77. ©2010 AACR.
Data from Suppression of Hypoxia-Inducible Factor 2α Restores p53 Activity via Hdm2 and Reverses Chemoresistance of Renal Carcinoma Cells
Authors: Roberts Andrew M. , Watson Ian R. , Evans Andrew J. , Foster David A. , Irwin Meredith S. , Ohh Michael
Published: March 2023

Abstract
p53 mutations are rarely detected in clear cell renal cell carcinoma (CCRCC), but, paradoxically, these tumors remain highly resistant to chemotherapy and death receptor–induced death. Here, we show that the accumulation of hypoxia-inducible factor 2α (HIF2α), a critical oncogenic event in CCRCC following the loss of von Hippel-Lindau (VHL) tumor suppressor protein, leads to Hdm2-mediated suppression of p53. Primary CCRCC specimens exhibiting strong hypoxic signatures show increased levels of activated nuclear phospho-Hdm2(Ser166), which is concomitant with low p53 expression. The abrogation of Hdm2-p53 interaction using the small-molecule Hdm2 inhibitor nutlin-3 or the downregulation of HIF2α via HIF2α-specific short hairpin RNA or wild-type VHL reconstitution restores p53 function and reverses the resistance of CCRCC cells to Fas-mediated and chemotherapy-induced cell death. These findings unveil a mechanistic link between HIF2α and p53 and provide a rationale for combining Hdm2 antagonists with chemotherapy for the treatment of CCRCC. [Cancer Res 2009;69(23):9056–64]
Data from C-Propeptides of Procollagens Iα1 and II that Differentially Accumulate in Enchondromas versus Chondrosarcomas Regulate Tumor Cell Survival and Migration
Authors: Vincourt Jean-Baptiste , Etienne Stéphanie , Cottet Justine , Delaunay Camille , Malanda Bantsimba , Lionneton Frédéric , Sirveaux François , Netter Patrick , Plénat François , Mainard Didier , Vignaud Jean-Michel , Magdalou Jacques
Published: March 2023

Abstract
Chondrogenic tumors that exhibit benign or malignant behaviors synthesize variable amounts of cartilage-like extracellular matrix. To define the regulators of these phenotypes, we performed a proteomic comparison of multiple human chondrogenic tumors, which revealed differential accumulation of the C-propeptides of procollagens Iα1 and II (PC1CP and PC2CP) in malignant versus benign tumors, respectively. Expression patterns of PC1CP correlated with levels of tumor vascularization, whereas expression patterns of PC2CP suggested its susceptibility to immobilization within the extracellular matrix. Prompted by these observations, we investigated the functions of recombinant PC1CP and PC2CP in the extracellular matrix in soluble or immobilized states. Each induced β1 integrin–mediated chondrocyte adhesion by distinct domains and efficacies, suggesting that they initiated distinct signaling pathways. Indeed, immobilized PC2CP, but not PC1CP, induced apoptosis of primary chondrocytes and EAhy926 endothelial cells. In contrast, soluble PC1CP, but not PC2CP, induced the migration of EAhy926 cells and increased vascular endothelial growth factor (VEGF) and CXCR4 expression in chondrocytes. Soluble PC2CP also increased VEGF expression, but along with a more pronounced effect on CXCR4 and matrix metalloproteinase 13 expression. Our findings suggest that PC1CP favors angiogenesis and tumor progression, but that PC2CP acts in a more complex manner, exerting antitumor and antiangiogenic properties through apoptosis induction when immobilized, but progression and metastasis when soluble. In summary, the relative levels of PC1CP and PC2CP and their interactions within the extracellular matrix contribute to tumor progression, angiogenesis, and metastasis in chondrogenic tumors. Cancer Res; 70(11); 4739–48. ©2010 AACR.
Data from Reprogramming Human Cancer Cells in the Mouse Mammary Gland
Authors: Bussard Karen M. , Boulanger Corinne A. , Booth Brian W. , Bruno Robert D. , Smith Gilbert H.
Published: March 2023

Abstract
The tissue microenvironment directs stem/progenitor cell behavior. Cancer cells are also influenced by the microenvironment. It has been shown that, when placed into blastocysts, cancer cells respond to embryonic cues and differentiate according to the tissue type encountered during ontological development. Previously, we showed that the mouse mammary gland was capable of redirecting adult mouse testicular and neural stem/progenitor cells toward a mammary epithelial cell fate during gland regeneration. Here, we report that human embryonal carcinoma cells proliferate and produce differentiated mammary epithelial cell progeny when mixed with mouse mammary epithelial cells and inoculated into the epithelium-free mammary fat pads of athymic nude mice. Fluorescence in situ hybridization confirmed the presence of human cell progeny in the mammary outgrowths for human centromeric DNA, as well as immunochemistry for human-specific breast epithelial cytokeratins and human-specific milk proteins in impregnated transplant hosts. It was found that the number of human cells increased by 66- to 660-fold during mammary epithelial growth and expansion as determined by human cytokeratin expression. All features found in primary outgrowths were recapitulated in the secondary outgrowths from chimeric implants. These results show that human embryonal carcinoma–derived progeny interact with mouse mammary cells during mammary gland regeneration and are directed to differentiate into cells that exhibit diverse mammary epithelial cell phenotypes. This is the first demonstration that human cells are capable of recognizing the signals generated by the mouse mammary gland microenvironment present during gland regeneration in vivo. Cancer Res; 70(15); 6336–43. ©2010 AACR.
Data from Tumor Cells Secrete Galectin-1 to Enhance Endothelial Cell Activity
Authors: Thijssen Victor L. , Barkan Batya , Shoji Hiroki , Aries Ingrid M. , Mathieu Véronique , Deltour Louise , Hackeng Tilman M. , Kiss Robert , Kloog Yoel , Poirier Françoise , Griffioen Arjan W.
Published: March 2023

Abstract
Tumor angiogenesis is a key event in cancer progression. Here, we report that tumors can stimulate tumor angiogenesis by secretion of galectin-1. Tumor growth and tumor angiogenesis of different tumor models are hampered in galectin-1–null (gal-1−/−) mice. However, tumor angiogenesis is less affected when tumor cells express and secrete high levels of galectin-1. Furthermore, tumor endothelial cells in gal-1−/− mice take up galectin-1 that is secreted by tumor cells. Uptake of galectin-1 by cultured endothelial cells specifically promotes H-Ras signaling to the Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase (Erk) kinase (Mek)/Erk cascade and stimulates endothelial cell proliferation and migration. Moreover, the activation can be blocked by galectin-1 inhibition as evidenced by hampered membrane translocation of H-Ras.GTP and impaired Raf/Mek/Erk phosphorylation after treatment with the galectin-1–targeting angiogenesis inhibitor anginex. Altogether, these data identify galectin-1 as a proangiogenic factor. These findings have direct implications for current efforts on galectin-1–targeted cancer therapies. Cancer Res; 70(15); 6216–24. ©2010 AACR.
Data from Clld7, A Candidate Tumor Suppressor on Chromosome 13q14, Regulates Pathways of DNA Damage/Repair and Apoptosis
Authors: Zhou Xiaobo , Münger Karl
Published: March 2023

Abstract
Chronic lymphocytic leukemia deletion gene 7 (Clld7) is a candidate tumor suppressor on chromosome 13q14. Clld7 encodes an evolutionarily conserved protein that contains an RCC1 domain plus broad complex, tramtrack, bric-a-brac (BTB), and POZ domains. In this study, we investigated the biological functions of Clld7 protein in inducible osteosarcoma cell lines. Clld7 induction inhibited cell growth, decreased cell viability, and increased γ-H2AX staining under conditions of caspase inhibition, indicating activation of the DNA damage/repair pathway. Real-time PCR analysis in tumor cells and normal human epithelial cells revealed Clld7 target genes that regulate DNA repair responses. Furthermore, depletion of Clld7 in normal human epithelial cells conferred resistance to apoptosis triggered by DNA damage. Taken together, the biological actions of Clld7 are consistent with those of a tumor suppressor. Cancer Res; 70(22); 9434–43. ©2010 AACR.
Data from Microtentacles Tip the Balance of Cytoskeletal Forces in Circulating Tumor Cells
Authors: Matrone Michael A. , Whipple Rebecca A. , Balzer Eric M. , Martin Stuart S.
Published: March 2023

Abstract
Detection of circulating tumor cells (CTC) is advancing as an effective predictor of patient outcome and therapeutic response. Unfortunately, our knowledge of CTC biology remains limited, and the impact of drug treatments on CTC metastatic potential is currently unclear. Improved CTC imaging in vivo and analysis of free-floating tumor cells now show that cytoskeletal regulation in CTCs contrasts starkly with tumor cells attached to extracellular matrix. In this review, we examine how persistent microtubule stabilization promotes the formation of microtentacles on the surface of detached breast tumor cells and enhances metastatic potential. Cancer Res; 70(20); 7737–41. ©2010 AACR.
Data from Regulation of Ceramide Synthase–Mediated Crypt Epithelium Apoptosis by DNA Damage Repair Enzymes
Authors: Rotolo Jimmy A. , Mesicek Judith , Maj Jerzy , Truman Jean-Philip , Haimovitz-Friedman Adriana , Kolesnick Richard , Fuks Zvi
Published: March 2023

Abstract
Acute endothelial cell apoptosis and microvascular compromise couple gastrointestinal tract irradiation to reproductive death of intestinal crypt stem cell clonogens (SCCs) following high-dose radiation. Genetic or pharmacologic inhibition of endothelial apoptosis prevents intestinal damage, but as the radiation dose is escalated, SCCs become directly susceptible to an alternate cell death mechanism, mediated via ceramide synthase (CS)–stimulated de novo synthesis of the proapoptotic sphingolipid ceramide, and p53-independent apoptosis of crypt SCCs. We previously reported that ataxia-telangiectasia mutated deficiency resets the primary radiation lethal pathway, allowing CS-mediated apoptosis at the low-dose range of radiation. The mechanism for this event, termed target reordering, remains unknown. Here, we show that inactivation of DNA damage repair pathways signals CS-mediated apoptosis in crypt SCCs, presumably via persistent unrepaired DNA double-strand breaks (DSBs). Genetic loss of function of sensors and transducers of DNA DSB repair confers the CS-mediated lethal pathway in intestines of sv129/B6Mre11ATLD1/ATLD1 and C57BL/6Prkdc/SCID (severe combined immunodeficient) mice exposed to low-dose radiation. In contrast, CS-mediated SCC lethality was mitigated in irradiated gain-of-function Rad50s/s mice, and epistasis studies order Rad50 upstream of Mre11. These studies suggest unrepaired DNA DSBs as causative in target reordering in intestinal SCCs. As such, we provide an in vivo model of DNA damage repair that is standardized, can be exploited to understand allele-specific regulation in intact tissue, and is pharmacologically tractable. Cancer Res; 70(3); 957– 67
Data from HER2 Silences Tumor Suppression in Breast Cancer Cells by Switching Expression of C/EBPβ Isoforms
Authors: Arnal-Estapé Anna , Tarragona Maria , Morales Mònica , Guiu Marc , Nadal Cristina , Massagué Joan , Gomis Roger R.
Published: March 2023

Abstract
Tumor progression requires ablation of suppressor functions mediated by transforming growth factor β (TGFβ) signaling and by oncogene-induced senescence (OIS), but how these functions are canceled in specific subtypes of breast cancer remains unknown. In this study, we show that HER2-overexpressing breast cancer cells avert TGFβ- and OIS-mediated tumor suppression by switching expression of 2 functionally distinct isoforms of the transcription factor C/EBPβ, which has been implicated previously in breast cancer development. HER2 signaling activates the translational regulatory factor CUGBP1, which favors the production of the transcriptionally inhibitory isoform LIP over that of the active isoform LAP. LIP overexpression prevents the assembly of LAP/Smad transcriptional repressor complexes on the MYC promoter in response to TGFβ, and interferes with activation of OIS responses. Treatment of HER2-transformed mammary epithelial cells with the HER2 antibody trastuzumab reduces LIP levels, restoring these suppressor responses. Our findings reveal a novel mechanism through which HER2 silences tumor suppression in a concerted manner, contributing to the potency of this oncogene in breast cancer. Cancer Res; 70(23); 9927–36. ©2010 AACR.
Data from Oncogenic Wip1 Phosphatase Is Inhibited by miR-16 in the DNA Damage Signaling Pathway
Authors: Zhang Xinna , Wan Guohui , Mlotshwa Sizolwenkosi , Vance Vicki , Berger Franklin G. , Chen Hexin , Lu Xiongbin
Published: March 2023

Abstract
Wild-type p53-induced phosphatase 1 (Wip1) was identified as an oncogene amplified and overexpressed in several human cancers. Recent evidence suggested that Wip1 is a critical inhibitor in the ATM/ATR-p53 DNA damage signaling pathway. Wip1 dephosphorylates several key DNA damage–responsive proteins and reverses DNA damage–induced cell cycle checkpoints. Previous reports showed that Wip1 was transcriptionally induced by p53 at the early stage of the DNA damage response. To investigate the temporal and functional regulation of Wip1, we identified a microRNA, miR-16, that specifically targets the mRNA of Wip1 and thus negatively regulates the expression level of Wip1. miR-16 itself is induced immediately after DNA damage. Therefore, the increase in Wip1 protein level is significantly postponed compared with that of its mRNA level, preventing a premature inactivation of ATM/ATR signaling and allowing a functional completion of the early DNA damage response. To better understand miR-16 biological functions in the context of cancer cells, we examined its expression in mammary tumor stem cells and found it to be markedly downregulated in mammary tumor stem cells. Overexpression of miR-16 or inhibition of Wip1 suppresses the self-renewal and growth of mouse mammary tumor stem cells and sensitizes MCF-7 human breast cancer cells to the chemotherapeutic drug doxorubicin. Together, our results suggest an important role of miR-16 in the regulation of Wip1 phosphatase in the DNA damage response and mammary tumorigenesis. Cancer Res; 70(18); 7176–86. ©2010 AACR.
Data from Visible Drug Delivery by Supramolecular Nanocarriers Directing to Single-Platformed Diagnosis and Therapy of Pancreatic Tumor Model
Authors: Kaida Sachiko , Cabral Horacio , Kumagai Michiaki , Kishimura Akihiro , Terada Yasuko , Sekino Masaki , Aoki Ichio , Nishiyama Nobuhiro , Tani Toru , Kataoka Kazunori
Published: March 2023

Abstract
Nanoparticle therapeutics are promising platforms for cancer therapy. However, it remains a formidable challenge to assess their distribution and clinical efficacy for therapeutic applications. Here, by using multifunctional polymeric micellar nanocarriers incorporating clinically approved gadolinium (Gd)–based magnetic resonance imaging contrast agents and platinum (Pt) anticancer drugs through reversible metal chelation of Pt, simultaneous imaging and therapy of an orthotopic animal model of intractable human pancreatic tumor was successfully performed without any serious toxicity. The strong tumor contrast enhancement achieved by the micelles correlated with the 24 times increase of r1 of the Gd chelates, the highest for the formulations using clinically approved Gd chelates reported to date. From the micro-synchrotron radiation X-ray fluorescence spectrometry scanning of the lesions, we confirmed that both the Gd chelates and Pt drugs delivered by the micelles selectively colocalized in the tumor interior. Our study provides new insights for the design of theranostic micelles with high contrast enhancement and site-specific clinical potential. Cancer Res; 70(18); 7031–41. ©2010 AACR.
Data from FKBPL Regulates Estrogen Receptor Signaling and Determines Response to Endocrine Therapy
Authors: McKeen Hayley D. , Byrne Christopher , Jithesh Puthen V. , Donley Christopher , Valentine Andrea , Yakkundi Anita , O'Rourke Martin , Swanton Charles , McCarthy Helen O. , Hirst David G. , Robson Tracy
Published: March 2023

Abstract
The HSP90 chaperone and immunophilin FKBPL is an estrogen-responsive gene that interacts with estogen receptor α (ERα) and regulates its levels. In this study, we explored the effects of FKBPL on breast cancer proliferation. Breast cancer cells stably overexpressing FKBPL became dependent on estrogen for their growth and were dramatically more sensitive to the antiestrogens tamoxifen and fulvestrant, whereas FKBPL knockdown reverses this phenotype. FKBPL knockdown also decreased the levels of the cell cycle inhibitor p21WAF1 and increased ERα phosphorylation on Ser118 in response to 17β-estradiol and tamoxifen. In support of the likelihood that these effects explained FKBPL-mediated cell growth inhibition and sensitivity to endocrine therapies, FKBPL expression was correlated with increased overall survival and distant metastasis-free survival in breast cancer patients. Our findings suggest that FKBPL may have prognostic value based on its impact on tumor proliferative capacity and sensitivity to endocrine therapies, which improve outcome. Cancer Res; 70(3); 1090–100
Data from Cediranib/AZD2171 Inhibits Bone and Brain Metastasis in a Preclinical Model of Advanced Prostate Cancer
Authors: Yin Juan Juan , Zhang Luhua , Munasinghe Jeeva , Linnoila R. Ilona , Kelly Kathleen
Published: March 2023

Abstract
Late stage or aggressive cancers exhibit metastatic growth at multiple sites, and the characterization of treatment response in various organs to drugs with potentially wide-ranging efficacy is needed. Tumor cells that induce angiogenesis are a common characteristic of metastatic disease, and clinically, antiangiogenic therapies have shown value in the setting of advanced cancer. However, recent preclinical studies have suggested that exposure to antiangiogenic drugs can increase tumor invasiveness and metastasis, making it important to determine which contexts antiangiogenic therapy is most appropriate. We describe here the effects of cediranib, a receptor tyrosine kinase inhibitor, in a model of advanced prostate cancer metastatic to skeleton and brain. Treatment with cediranib decreased metastatic tumor burden in the brain and bone, decreased cerebral vasogenic edema, and improved survival, despite increasing the invasive histology of brain metastases. Short-duration cediranib treatment given at the time of tumor cell dissemination was sufficient to inhibit the establishment and subsequent growth of bone metastases, although brain metastases were subject to rebound growth after the discontinuation of cediranib. Distinct growth patterns at different organ sites in the same animal showed that certain tumor microenvironments such as bone may be most amenable to interventions by anti–vascular endothelial growth factor (VEGF) therapies. In addition, anti-VEGF treatment may be of utility in decreasing the rapid growth of solid brain metastases and vasogenic edema in patients with advanced cancer, leading to reduced morbidity and associated clinical benefit. Cancer Res; 70(21); 8662–73. ©2010 AACR.
Data from hnRNP A2/B1 Modulates Epithelial-Mesenchymal Transition in Lung Cancer Cell Lines
Authors: Tauler Jordi , Zudaire Enrique , Liu Huaitian , Shih Joanna , Mulshine James L.
Published: March 2023

Abstract
Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) has been reported to be overexpressed in lung cancer and in other cancers such as breast, pancreas, and liver. However, a mechanism linking hnRNP A2/B1 overexpression and progression to cancer has not yet been definitively established. To elucidate this mechanism, we have silenced hnRNPA2/B1 mRNA in non–small-cell lung cancer cell lines A549, H1703, and H358. These cell lines present different levels of expression of epithelial-to-mesenchymal transition (EMT) markers such as E-cadherin, fibronectin, and vimentin. Microarray expression analysis was performed to evaluate the effect of silencing hnRNP A2/B1 in A549 cells. We identified a list of target genes, affected by silencing of hnRNP A2/B1, that are involved in regulation of migration, proliferation, survival, and apoptosis. Silencing hnRNP A2/B1 induced formation of cell clusters and increased proliferation. In the anchorage-independent assay, silencing hnRNP A2/B1 increased colony formation by 794% in A549 and 174% in H1703 compared with a 25% increase in proliferation, in both cell lines, in a two-dimensional proliferation assay. Silencing hnRNP A2/B1 decreased migration in intermediate cell line A549 and mesenchymal cell line H1703; however, no changes in proliferation were observed in epithelial cell line H358. Silencing hnRNP A2/B1 in A549 and H1703 cells correlated with an increase of E-cadherin expression and downregulation of the E-cadherin inhibitors Twist1 and Snai1. These data suggest that expression of hnRNP A2/B1 may play a role in EMT, in nonepithelial lung cancer cell lines A549 and H1703, through the regulation of E-cadherin expression. Cancer Res; 70(18); 7137–47. ©2010 AACR.
Data from The miR-17-92 Cluster of MicroRNAs Confers Tumorigenicity by Inhibiting Oncogene-Induced Senescence
Authors: Hong Lixin , Lai Maoyi , Chen Michelle , Xie Changchuan , Liao Rong , Kang Young Jun , Xiao Changchun , Hu Wen-Yuan , Han Jiahuai , Sun Peiqing
Published: March 2023

Abstract
In mammalian cells, activation of oncogenes usually triggers innate tumor-suppressing defense mechanisms, including apoptosis and senescence, which are compromised by additional mutations before cancers are developed. The miR-17-92 gene cluster, a polycistron encoding six microRNAs (miRNA), is frequently overexpressed in human cancers and has been shown to promote several aspects of oncogenic transformation, including evasion of apoptosis. In the current study, we show a new role of miR-17-92 in inhibiting oncogenic ras-induced senescence. Further dissection of the miRNA components in this cluster reveals that the miR-17/20a seed family accounts for this antisenescence activity. miR-17 and miR-20a are both necessary and sufficient for conferring resistance to ras-induced senescence by directly targeting p21WAF1, a key effector of senescence. By contrast, these components are not essential for the ability of miR-17-92 to evade Myc-induced apoptosis. Moreover, disruption of senescence by miR-17-92 or its miR-17/20a components leads to enhanced oncogenic transformation by activated ras in primary human cells. Taken together with previous reports that miR-17-92 inhibits apoptosis by suppressing Pten via the miR-19 components, our results indicate that this miRNA cluster promotes tumorigenesis by antagonizing both tumor-suppressing mechanisms, apoptosis, and senescence, through the activities of different miRNA components encoded in this cluster. Cancer Res; 70(21); 8547–57. ©2010 AACR.