bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Association of Specific Genotypes in Metastatic Suppressor HTPAP with Tumor Metastasis and Clinical Prognosis in Hepatocellular Carcinoma
Authors: Ren Ning , Wu Jin-Cai , Dong Qiong-Zhu , Sun Hai-Jing , Jia Hu-Liang , Li Guo-Cai , Sun Bing-Sheng , Dai Chun , Shi Jiong , Wei Jin-Wang , Sheng Yuan-Yuan , Zhou Hai-Jun , Ye Qing-Hai , Qin Lun-Xiu
Published: March 2024

Abstract
The phosphatidic acid phosphatase HTPAP has been defined as a metastatic suppressor of hepatocellular carcinoma (HCC), but little is known about its function or potential applications as a prognostic marker. In this study, we analyzed patterns of HTPAP genetic variation and gene expression in 864 patients who underwent HCC resection, assessing these patterns for correlations to tumor metastasis potential. Focusing on two tagSNPs that were selected (+357G/C and +1838A/G), we found that only the +357G/C genotype was significantly associated with HTPAP mRNA and protein expression levels and the probability of metastasis. In an independent cohort of 665 HCC patients, we determined that the +357G/C genotype was associated with shorter time to recurrence and overall survival. Together, these results indicated that the HTPAP tagSNP +357 GG+GC genotypes may influence HCC metastatic potential and clinical prognosis by down-regulating HTPAP expression. Extending these results, a global expression profiling analysis identified 41 genes including the pro-inflammatory genes IL-8 and TLR2 that were significantly overexpressed in the +357 GG+GC group, as possible coregulated markers with HTPAP. Together, our findings identify an HTPAP genotype and associated gene expression pattern that favors metastasis progression and that could be used to predict tumor metastasis and prognosis in HCC patients. Cancer Res; 71(9); 3278–86. ©2011 AACR.
Data from Interaction between MYC and MCL1 in the Genesis and Outcome of Non–Small-Cell Lung Cancer
Authors: Allen Thaddeus D. , Zhu Chang Qi , Jones Kirk D. , Yanagawa Naoki , Tsao Ming-Sound , Bishop J. Michael
Published: March 2024

Abstract
MYC exerts both positive and negative functions in cancer cells, such that its procancerous effects are unmasked only after its anticancer effects are blocked. Here we used multiple mouse models of lung adenocarcinoma to identify genetic events that can cooperate with MYC activation to promote the genesis of non–small-cell lung cancer (NSCLC), the most common form of lung cancer in humans. MYC overexpression targeted to pulmonary alveolar cells was sufficient to induce lung adenomas and carcinomas. Tumorigenesis was assisted by either spontaneous mutations in Kras or experimental introduction of activated RAS, but investigations revealed that additional events were required to circumvent apoptosis, one of the most significant negative functions exerted by MYC. We determined that overexpression of the antiapoptotic protein MCL1 was sufficient to circumvent apoptosis in this setting. Previous clinical studies have indicated that prognosis of human NSCLC is not associated with MCL1, despite its overexpression in many NSCLCs. In reexamining the prognostic value in this setting, we found that MCL1 overexpression does correlate with poor patient survival, but only when accompanied by MYC overexpression. Our findings therefore produce a convergence of mouse and human results that explain how MCL1 can block an important negative consequence of MYC overexpression in both experimental models and clinical cases of NSCLC. Cancer Res; 71(6); 2212–21. ©2011 AACR.
Data from Small Molecule Kinase Inhibitor Screen Identifies Polo-Like Kinase 1 as a Target for Neuroblastoma Tumor-Initiating Cells
Authors: Grinshtein Natalie , Datti Alessandro , Fujitani Mayumi , Uehling David , Prakesch Michael , Isaac Methvin , Irwin Meredith S. , Wrana Jeffrey L. , Al-awar Rima , Kaplan David R.
Published: March 2024

Abstract
Neuroblastoma (NB) is an often fatal pediatric tumor of neural crest origin. We previously isolated NB tumor-initiating cells (NB TIC) from bone marrow metastases that resemble cancer stem cells and form metastatic NB in immunodeficient animals with as few as ten cells. To identify signaling pathways important for the survival and self-renewal of NB TICs and potential therapeutic targets, we screened a small molecule library of 143 protein kinase inhibitors, including 33 in clinical trials. Cytostatic or cytotoxic drugs were identified that targeted PI3K (phosphoinositide 3-kinase)/Akt, PKC (protein kinase C), Aurora, ErbB2, Trk, and Polo-like kinase 1 (PLK1). Treatment with PLK1 siRNA or low nanomolar concentrations of BI 2536 or BI 6727, PLK1 inhibitors in clinical trials for adult malignancies, were cytotoxic to TICs whereas only micromolar concentrations of the inhibitors were cytotoxic for normal pediatric neural stem cells. Furthermore, BI 2536 significantly inhibited TIC tumor growth in a therapeutic xenograft model, both as a single agent and in combination with irinotecan, an active agent for relapsed NB. Our findings identify candidate kinases that regulate TIC growth and survival and suggest that PLK1 inhibitors are an attractive candidate therapy for metastatic NB. Cancer Res; 71(4); 1385–95. ©2011 AACR.
Data from Parallel High-Throughput RNA Interference Screens Identify PINK1 as a Potential Therapeutic Target for the Treatment of DNA Mismatch Repair–Deficient Cancers
Authors: Martin Sarah A. , Hewish Madeleine , Sims David , Lord Christopher J. , Ashworth Alan
Published: March 2024

Abstract
Synthetic lethal approaches to cancer treatment have the potential to deliver relatively large therapeutic windows and therefore significant patient benefit. To identify potential therapeutic approaches for cancers deficient in DNA mismatch repair (MMR), we have carried out parallel high-throughput RNA interference screens using tumor cell models of MSH2- and MLH1-related MMR deficiency. We show that silencing of the PTEN-induced putative kinase 1 (PINK1), is synthetically lethal with MMR deficiency in cells with MSH2, MLH1, or MSH6 dysfunction. Inhibition of PINK1 in an MMR-deficient background results in an elevation of reactive oxygen species and the accumulation of both nuclear and mitochondrial oxidative DNA lesions, which likely limit cell viability. Therefore, PINK1 represents a potential therapeutic target for the treatment of cancers characterized by MMR deficiency caused by a range of different gene deficiencies. Cancer Res; 71(5); 1836–48. ©2011 AACR.
Data from Chromosomal Instability Confers Intrinsic Multidrug Resistance
Authors: Lee Alvin J.X. , Endesfelder David , Rowan Andrew J. , Walther Axel , Birkbak Nicolai J. , Futreal P. Andrew , Downward Julian , Szallasi Zoltan , Tomlinson Ian P.M. , Howell Michael , Kschischo Maik , Swanton Charles
Published: March 2024

Abstract
Aneuploidy is associated with poor prognosis in solid tumors. Spontaneous chromosome missegregation events in aneuploid cells promote chromosomal instability (CIN) that may contribute to the acquisition of multidrug resistance in vitro and heighten risk for tumor relapse in animal models. Identification of distinct therapeutic agents that target tumor karyotypic complexity has important clinical implications. To identify distinct therapeutic approaches to specifically limit the growth of CIN tumors, we focused on a panel of colorectal cancer (CRC) cell lines, previously classified as either chromosomally unstable (CIN+) or diploid/near-diploid (CIN−), and treated them individually with a library of kinase inhibitors targeting components of signal transduction, cell cycle, and transmembrane receptor signaling pathways. CIN+ cell lines displayed significant intrinsic multidrug resistance compared with CIN− cancer cell lines, and this seemed to be independent of somatic mutation status and proliferation rate. Confirming the association of CIN rather than ploidy status with multidrug resistance, tetraploid isogenic cells that had arisen from diploid cell lines displayed lower drug sensitivity than their diploid parental cells only with increasing chromosomal heterogeneity and isogenic cell line models of CIN+ displayed multidrug resistance relative to their CIN− parental cancer cell line derivatives. In a meta-analysis of CRC outcome following cytotoxic treatment, CIN+ predicted worse progression-free or disease-free survival relative to patients with CIN− disease. Our results suggest that stratifying tumor responses according to CIN status should be considered within the context of clinical trials to minimize the confounding effects of tumor CIN status on drug sensitivity. Cancer Res; 71(5); 1858–70. ©2011 AACR.
Data from Expression Profiling of Liposarcoma Yields a Multigene Predictor of Patient Outcome and Identifies Genes That Contribute to Liposarcomagenesis
Authors: Gobble Ryan M. , Qin Li-Xuan , Brill Elliott R. , Angeles Christina V. , Ugras Stacy , O'Connor Rachael B. , Moraco Nicole H. , DeCarolis Penelope L. , Antonescu Cristina , Singer Samuel
Published: March 2024

Abstract
Liposarcomas are the most common type of soft tissue sarcoma but their genetics are poorly defined. To identify genes that contribute to liposarcomagenesis and serve as prognostic candidates, we undertook expression profiling of 140 primary liposarcoma samples, which were randomly split into training set (n = 95) and test set (n = 45). A multigene predictor for distant recurrence-free survival (DRFS) was developed by the supervised principal component method. Expression levels of the 588 genes in the predictor were used to calculate a risk score for each patient. In validation of the predictor in the test set, patients with low risk score had a 3-year DRFS of 83% versus 45% for high risk score patients (P = 0.001). The HR for high versus low score, adjusted for histologic subtype, was 4.42 (95% CI, 1.26–15.55; P = 0.021). The concordance probability for risk score was 0.732. In contrast, the concordance probability for histologic subtype, which had been considered the best predictor of outcome in liposarcoma, was 0.669. Genes related to adipogenesis, DNA replication, mitosis, and spindle assembly checkpoint control were all highly represented in the multigene predictor. Three genes from the predictor, TOP2A, PTK7, and CHEK1, were found to be overexpressed in liposarcoma samples of all five subtypes and in liposarcoma cell lines. RNAi-mediated knockdown of these genes in liposarcoma cell lines reduced proliferation and invasiveness and increased apoptosis. Taken together, our findings identify genes that seem to be involved in liposarcomagenesis and have promise as therapeutic targets, and support the use of this multigene predictor to improve risk stratification for individual patients with liposarcoma. Cancer Res; 71(7); 2697–705. ©2011 AACR.
Data from p53 Modulates Acquired Resistance to EGFR Inhibitors and Radiation
Authors: Huang Shyhmin , Benavente Sergio , Armstrong Eric A. , Li Chunrong , Wheeler Deric L. , Harari Paul M.
Published: March 2024

Abstract
There is presently great interest in mechanisms of acquired resistance to epidermal growth factor receptor (EGFR) inhibitors that are now being used widely in the treatment of a variety of common human cancers. To investigate these mechanisms, we established EGFR inhibitor–resistant clones from non–small cell lung cancer cells. A comparative analysis revealed that acquired resistance to EGFR inhibitors was associated consistently with the loss of p53 and cross-resistance to radiation. To examine the role of p53, we first knocked down p53 in sensitive parental cells and found a reduction in sensitivity to both EGFR inhibitors and radiation. Conversely, restoration of functional p53 in EGFR inhibitor–resistant cells was sufficient to resensitize them to EGFR inhibitors or radiation in vitro and in vivo. Further studies indicate that p53 may enhance sensitivity to EGFR inhibitors and radiation via induction of cell-cycle arrest, apoptosis, and DNA damage repair. Taken together, these findings suggest a central role of p53 in the development of acquired resistance to EGFR inhibitors and prompt consideration to apply p53 restoration strategies in future clinical trials that combine EGFR inhibitors and radiation. Cancer Res; 71(22); 7071–9. ©2011 AACR.
Data from EGFR Nuclear Translocation Modulates DNA Repair following Cisplatin and Ionizing Radiation Treatment
Authors: Liccardi Gianmaria , Hartley John A. , Hochhauser Daniel
Published: March 2024

Abstract
Epidermal growth factor receptor (EGFR) overexpression is associated with resistance to chemotherapy and radiotherapy. It modulates DNA repair after radiation-induced damage through association with the catalytic subunit of DNA protein kinase (DNA-PKcs). We investigated the role of EGFR nuclear import and its association with DNA-PKcs on DNA repair after exposure to cisplatin or ionizing radiation (IR). The model system was based on EGFR-null murine NIH3T3 fibroblasts in which EGFR expression was restored with isoforms that were wild-type (wt), derived from human cancers (L858R, EGFRvIII), or mutated in the nuclear localization signal (NLS) sequence. In cells expressing wtEGFR or EGFRvIII, there was complete unhooking of cisplatin-induced interstrand cross-links and repair of IR-induced strand breaks. In contrast, cells expressing L858R or NLS mutations showed reduced unhooking of interstrand cross-links and repair of strand breaks. Immunoprecipitation showed wtEGFR and EGFRvIII binding to DNA-PKcs, increasing 2-fold 18 hours after cisplatin therapy. Confocal microscopy and proximity ligation assay showed that this interaction in the cytoplasm and nucleus was associated with increased DNA protein kinase complex (DNA-PK) activity. Cells expressing the EGFR L858R mutation, which has constitutive kinase activity, exhibited reduced DNA repair without nuclear localization. EGFR-NLS mutants showed impaired nuclear localization and DNA-PKcs association with reduced DNA repair and DNA-PK kinase activity. In summary, EGFR nuclear localization was required for modulation of cisplatin and IR-induced repair of DNA damage. EGFR–DNA-PKcs binding was induced by cisplatin or IR but not by EGFR nuclear translocation per se. Our findings show that EGFR subcellular distribution can modulate DNA repair kinetics, with implications for design of EGFR-targeted combinational therapies. Cancer Res; 71(3); 1103–14. ©2011 AACR.
Data from A Simple Approach to Cancer Therapy Afforded by Multivalent Pseudopeptides That Target Cell-Surface Nucleoproteins
Authors: Destouches Damien , Page Nicolas , Hamma-Kourbali Yamina , Machi Valérie , Chaloin Olivier , Frechault Sophie , Birmpas Charalampos , Katsoris Panagiotis , Beyrath Julien , Albanese Patricia , Maurer Marie , Carpentier Gilles , Strub Jean-Marc , Van Dorsselaer Alain , Muller Sylviane , Bagnard Dominique , Briand Jean Paul , Courty José
Published: March 2024

Abstract
Recent studies have implicated the involvement of cell surface forms of nucleolin in tumor growth. In this study, we investigated whether a synthetic ligand of cell-surface nucleolin known as N6L could exert antitumor activity. We found that N6L inhibits the anchorage-dependent and independent growth of tumor cell lines and that it also hampers angiogenesis. Additionally, we found that N6L is a proapoptotic molecule that increases Annexin V staining and caspase-3/7 activity in vitro and DNA fragmentation in vivo. Through affinity isolation experiments and mass-spectrometry analysis, we also identified nucleophosmin as a new N6L target. Notably, in mouse xenograft models, N6L administration inhibited human tumor growth. Biodistribution studies carried out in tumor-bearing mice indicated that following administration N6L rapidly localizes to tumor tissue, consistent with its observed antitumor effects. Our findings define N6L as a novel anticancer drug candidate warranting further investigation. Cancer Res; 71(9); 3296–305. ©2011 AACR.
Data from p53-Responsive miR-194 Inhibits Thrombospondin-1 and Promotes Angiogenesis in Colon Cancers
Authors: Sundaram Prema , Hultine Stacy , Smith Lauren M. , Dews Michael , Fox Jamie L. , Biyashev Dauren , Schelter Janell M. , Huang Qihong , Cleary Michele A. , Volpert Olga V. , Thomas-Tikhonenko Andrei
Published: March 2024

Abstract
Thrombospondin-1 (TSP-1) is an endogenous inhibitor of angiogenesis encoded by the THBS1 gene, whose promoter is activated by p53. In advanced colorectal cancers (CRC), its expression is sustained or even slightly increased despite frequent loss of p53. Here, we determined that in HCT116 CRC cells, p53 activates the THBS1 primary transcript, but fails to boost THBS1 mRNA or protein levels, implying posttranscriptional regulation by microRNAs (miRNA). In a global miRNA gain-of-function screen done in the Dicer-deficient HCT116 variant, several miRNAs negatively regulated THBS1 mRNA and protein levels, one of them being miR-194. Notably, in agreement with published data, p53 upregulated miR-194 expression in THBS1 retrovirus-transduced HCT116 cells, leading to decreased TSP-1 levels. This negative effect was mediated by a single miR-194 complementary site in the THBS1 3′-untranslated region, and its elimination resulted in TSP-1 reactivation, impaired angiogenesis in Matrigel plugs, and reduced growth of HCT116 xenografts. Conversely, transient overexpression of miR-194 in HCT116/THBS1 cells boosted Matrigel angiogenesis, and its stable overexpression in Ras-induced murine colon carcinomas increased microvascular densities and vessel sizes. Although the overall contribution of miR-194 to neoplastic growth is context dependent, p53-induced activation of this GI tract–specific miRNA during ischemia could promote angiogenesis and facilitate tissue repair. Cancer Res; 71(24); 7490–501. ©2011 AACR.
Data from Hippo/Mst1 Stimulates Transcription of the Proapoptotic Mediator NOXA in a FoxO1-Dependent Manner
Authors: Valis Karel , Prochazka Lubomir , Boura Evzen , Chladova Jaromira , Obsil Tomas , Rohlena Jakub , Truksa Jaroslav , Dong Lan-Feng , Ralph Stephen J. , Neuzil Jiri
Published: March 2024

Abstract
The proapoptotic protein Noxa, a member of the BH3-only Bcl-2 protein family, can effectively induce apoptosis in cancer cells, although the relevant regulatory pathways have been obscure. Previous studies of the cytotoxic effects of α-tocopheryl succinate (α-TOS) on cancer cells identified a mechanism whereby α-TOS caused apoptosis requiring the Noxa-Bak axis. In the present study, ab initio analysis revealed a conserved FoxO-binding site (DBE; DAF-16 binding element) in the NOXA promoter, and specific affinity of FoxO proteins to this DBE was confirmed by fluorescence anisotropy. FoxO1 and FoxO3a proteins accumulated in the nucleus of α-TOS–treated cells, and the drug-induced specific FoxO1 association with the NOXA promoter and its activation were validated by chromatin immunoprecipitation. Using siRNA knockdown, a specific role for the FoxO1 protein in activating NOXA transcription in cancer cells was identified. Furthermore, the proapoptotic kinase Hippo/Mst1 was found to be strongly activated by α-TOS, and inhibiting Hippo/Mst1 by specific siRNA prevented phosphorylation of FoxO1 and its nuclear translocation, thereby reducing levels of NOXA transcription and apoptosis in cancer cells exposed to α-TOS. Thus, we have demonstrated that anticancer drugs, exemplified by α-TOS, induce apoptosis by a mechanism involving the Hippo/Mst1-FoxO1-Noxa pathway. We propose that activation of this pathway provides a new paradigm for developing targeted cancer treatments. Cancer Res; 71(3); 946–54. ©2011 AACR.
Data from Cytoplasmic CUL9/PARC Ubiquitin Ligase Is a Tumor Suppressor and Promotes p53-Dependent Apoptosis
Authors: Pei Xin-Hai , Bai Feng , Li Zhijun , Smith Matthew D. , Whitewolf Gabrielle , Jin Ran , Xiong Yue
Published: March 2024

Abstract
A wide range of cell stresses, including DNA damage, signal to p53 through posttranslational modification of p53. The cytoplasmic functions of p53 are emerging as an important constituent of role of p53 in tumor suppression. Here, we report that deletion of the Cul9 (formerly Parc) gene, which encodes an E3 ubiquitin ligase that binds to p53 and localizes in the cytoplasm, resulted in spontaneous tumor development, accelerated Eμ-Myc–induced lymphomagenesis, and rendered mice susceptible to carcinogenesis. Cul9-p53 double-mutant mice exhibited indistinguishable tumor phenotypes as p53 single-mutant mice, indicating that the function of Cul9 in tumor suppression is largely mediated by p53. Deletion of Cul9 had no significant effect on cell-cycle progression, but attenuated DNA damage–induced apoptosis. Ectopic expression of wild-type CUL9, but not a point mutant CUL9 deficient in p53 binding, promotes apoptosis. These results show CUL9 as a potential p53-activating E3 ligase in the cytoplasm. Cancer Res; 71(8); 2969–77. ©2011 AACR.
Data from EMT and Stem Cell–Like Properties Associated with miR-205 and miR-200 Epigenetic Silencing Are Early Manifestations during Carcinogen-Induced Transformation of Human Lung Epithelial Cells
Authors: Tellez Carmen S. , Juri Daniel E. , Do Kieu , Bernauer Amanda M. , Thomas Cindy L. , Damiani Leah A. , Tessema Mathewos , Leng Shuguang , Belinsky Steven A.
Published: March 2024

Abstract
Epithelial-to-mesenchymal transition (EMT) is strongly associated with cancer progression, but its potential role during premalignant development has not been studied. Here, we show that a 4-week exposure of immortalized human bronchial epithelial cells (HBEC) to tobacco carcinogens can induce a persistent, irreversible, and multifaceted dedifferentiation program marked by EMT and the emergence of stem cell–like properties. EMT induction was epigenetically driven, initially by chromatin remodeling through H3K27me3 enrichment and later by ensuing DNA methylation to sustain silencing of tumor-suppressive microRNAs (miRNA), miR-200b, miR-200c, and miR-205, which were implicated in the dedifferentiation program in HBECs and also in primary lung tumors. Carcinogen-treated HBECs acquired stem cell–like features characterized by their ability to form spheroids with branching tubules and enrichment of the CD44high/CD24low, CD133, and ALDH1 stem cell–like markers. miRNA overexpression studies indicated that regulation of the EMT, stem-like, and transformed phenotypes in HBECs were distinct events. Our findings extend present concepts of how EMT participates in cancer pathophysiology by showing that EMT induction can participate in cancer initiation to promote the clonal expansion of premalignant lung epithelial cells. Cancer Res; 71(8); 3087–97. ©2011 AACR.
Data from Combination Therapy with HSP90 Inhibitor 17-DMAG Reconditions the Tumor Microenvironment to Improve Recruitment of Therapeutic T cells
Authors: Rao Aparna , Taylor Jennifer L. , Chi-Sabins Nina , Kawabe Mayumi , Gooding William E. , Storkus Walter J.
Published: March 2024

Abstract
Ineffective recognition of tumor cells by CD8+ T cells is a limitation of cancer immunotherapy. Therefore, treatment regimens that coordinately promote enhanced antitumor CD8+ T-cell activation, delivery, and target cell recognition should yield greater clinical benefit. Using an MCA205 sarcoma model, we show that in vitro treatment of tumor cells with the HSP90 inhibitor 17-DMAG results in the transient (proteasome-dependent) degradation of the HSP90 client protein EphA2 and the subsequent increased recognition of tumor cells by Type-1 anti-EphA2 CD8+ T cells. In vivo administration of 17-DMAG to tumor-bearing mice led to slowed tumor growth, enhanced/prolonged recognition of tumor cells by anti-EphA2 CD8+ T cells, reduced levels of myeloid-derived suppressor cells and regulatory T cells in the tumor microenvironment, and activation of tumor-associated vascular endothelial cells in association with elevated levels of Type-1 tumor-infiltrating lymphocytes. When combined with EphA2-specific active vaccination or the adoptive transfer of EphA2-specific CD8+ T cells, 17-DMAG cotreatment yielded a superior tumor therapeutic regimen that was capable of rendering animals free of disease. Taken together, our findings indicate that 17-DMAG functions as an immune adjuvant in the context of vaccines targeting EphA2. Cancer Res; 72(13); 3196–206. ©2012 AACR.
Data from Angiopoietin-1 and -2 Exert Antagonistic Functions in Tumor Angiogenesis, yet Both Induce Lymphangiogenesis
Authors: Fagiani Ernesta , Lorentz Pascal , Kopfstein Lucie , Christofori Gerhard
Published: March 2024

Abstract
Members of the Angiopoietin family regulate various aspects of physiologic and pathologic angiogenesis. Although Angiopoietin-1 (Ang-1) decreases endothelial cell permeability and increases vascular stabilization via recruitment of pericytes and smooth muscle cells to growing blood vessels, Angiopoietin-2 (Ang-2) mediates angiogenic sprouting and vascular regression. In this study, we used the Rip1Tag2 transgenic mouse model of pancreatic β-cell carcinogenesis to investigate the roles of Ang-1 and Ang-2 in tumor angiogenesis and tumor progression. On their own, transgenic expression of human Ang-1 or Ang-2 in pancreatic β cells caused formation of peri-insular lymphatic vessels in the absence of effects on blood vessel density, islet morphology, or physiology. When crossed to Rip1Tag2 mice, both Ang-1–and Ang-2–expressing β-cell tumors showed increased peritumoral lymphangiogenesis in the absence of metastasis to local lymph nodes or distant organs. There was no alteration in tumor outgrowth, blood vessel density, or vessel maturation in Ang-1–expressing tumors. In contrast, Ang-2–expressing tumors exhibited diminished pericyte recruitment to blood vessels that were dilated, nonfunctional, and highly permeable. These tumors were hemorrhagic, highly infiltrated by leukocytes, and impaired in outgrowth. Together, our findings establish that Ang-2 antagonizes Ang-1 function, leading to excessive vessel sprouting with impaired pericyte recruitment and vessel stabilization. The poor perfusion of immature blood vessels results in retarded tumor growth, defining an important pathophysiologic pathway required for efficient tumorigenesis. Cancer Res; 71(17); 5717–27. ©2011 AACR.
Data from An Iron Regulatory Gene Signature Predicts Outcome in Breast Cancer
Authors: Miller Lance D. , Coffman Lan G. , Chou Jeff W. , Black Michael A. , Bergh Jonas , D'Agostino Ralph , Torti Suzy V. , Torti Frank M.
Published: March 2024

Abstract
Changes in iron regulation characterize the malignant state. However, the pathways that effect these changes and their specific impact on prognosis remain poorly understood. We capitalized on publicly available microarray datasets comprising 674 breast cancer cases to systematically investigate how expression of genes related to iron metabolism is linked to breast cancer prognosis. Of 61 genes involved in iron regulation, 49% were statistically significantly associated with distant metastasis-free survival. Cases were divided into test and training cohorts, and the supervised principal component method was used to stratify cases into risk groups. Optimal risk stratification was achieved with a model comprising 16 genes, which we term the iron regulatory gene signature (IRGS). Multivariable analysis revealed that the IRGS contributes information not captured by conventional prognostic indicators (HR = 1.61; 95% confidence interval: 1.16–2.24; P = 0.004). The IRGS successfully stratified homogeneously treated patients, including ER+ patients treated with tamoxifen monotherapy, both with (P = 0.006) and without (P = 0.03) lymph node metastases. To test whether multiple pathways were embedded within the IRGS, we evaluated the performance of two gene dyads with known roles in iron biology in ER+ patients treated with tamoxifen monotherapy (n = 371). For both dyads, gene combinations that minimized intracellular iron content [anti-import: TFRCLow/HFEHigh; or pro-export: SLC40A1 (ferroportin)High/HAMPLow] were associated with favorable prognosis (P < 0.005). Although the clinical utility of the IRGS will require further evaluation, its ability to both identify high-risk patients within traditionally low-risk groups and low-risk patients within high-risk groups has the potential to affect therapeutic decision making. Cancer Res; 71(21); 6728–37. ©2011 AACR.
Data from INT6/EIF3E Interacts with ATM and Is Required for Proper Execution of the DNA Damage Response in Human Cells
Authors: Morris Christelle , Tomimatsu Nozomi , Richard Derek J. , Cluet David , Burma Sandeep , Khanna Kum Kum , Jalinot Pierre
Published: March 2024

Abstract
Altered expression of the INT6 gene, encoding the e subunit of the translational initiation factor eIF3, occurs in human breast cancers, but how INT6 relates to carcinogenesis remains unestablished. Here, we show that INT6 is involved in the DNA damage response. INT6 was required for cell survival following γ-irradiation and G2–M checkpoint control. RNA interference–mediated silencing of INT6 reduced phosphorylation of the checkpoint kinases CHK1 and CHK2 after DNA damage. In addition, INT6 silencing prevented sustained accumulation of ataxia telangiectasia mutated (ATM) at DNA damage sites in cells treated with γ-radiation or the radiomimetic drug neocarzinostatin. Mechanistically, this result could be explained by interaction of INT6 with ATM, which together with INT6 was recruited to the sites of DNA damage. Finally, INT6 silencing also reduced ubiquitylation events that promote retention of repair proteins at DNA lesions. Accordingly, accumulation of the repair factor BRCA1 was defective in the absence of INT6. Our findings reveal unexpected and striking connections of INT6 with ATM and BRCA1 and suggest that the protective action of INT6 in the onset of breast cancers relies on its involvement in the DNA damage response. Cancer Res; 72(8); 2006–16. ©2012 AACR.
Data from Potentiation of the Novel Topoisomerase I Inhibitor Indenoisoquinoline LMP-400 by the Cell Checkpoint and Chk1-Chk2 Inhibitor AZD7762
Authors: Aris Sheena M. , Pommier Yves
Published: March 2024

Abstract
Novel topoisomerase I (Top1) inhibitors are in clinical development to circumvent the drawbacks of camptothecins (CPT). Here, we report molecular investigations into LMP-400, an indenoisoquinoline Top1 inhibitor in phase 1 clinical trial, by itself and in combination with the cell-cycle checkpoint inhibitor AZD7762. We examined drug effects on DNA replication and killing of cancer cells and found that LMP-400 showed synergistic antiproliferative activity when combined with AZD7762 in human colon carcinoma cells. Inhibition of S-phase progression and bromodeoxyuridine incorporation were similarly induced by LMP-400 and CPT and were abrogated by AZD7762. Replication studied by single DNA molecule analyses and immunofluorescence microscopy (molecular combing) showed rapid inhibition of fork progression in response to LMP-400 treatment with subsequent recapitulation after AZD7762 addition. AZD7762 inhibited both the activation/autophosphosphorylation of Chk1 and Chk2 at nanomolar concentrations in LMP-400–treated cells. This potent dual inhibition of Chk1 and Chk2 by AZD7762 was below the drug concentrations required to abrogate cell-cycle inhibition and produce synergism with LMP-400. Also, the synergism was independent of Chk2 both in Chk2-complemented cells and Chk2 knockout cells, suggesting additional mechanisms for cell-cycle abrogation by AZD7762. Together, our findings show a rationale for combining cell-cycle checkpoint inhibitors with the novel non-CPT indenoisoquinoline Top1 inhibitors. Cancer Res; 72(4); 979–89. ©2011 AACR.
Data from Effective Combination Therapy for Malignant Glioma with TRAIL-Secreting Mesenchymal Stem Cells and Lipoxygenase Inhibitor MK886
Authors: Kim Seong Muk , Woo Ji Sun , Jeong Chang Hyun , Ryu Chung Heon , Lim Jung Yeon , Jeun Sin-Soo
Published: March 2024

Abstract
The apoptotic ligand TRAIL is believed to have promise as a cancer gene therapy, yet many types of cancer, including gliomas, have exhibited resistance to TRAIL-induced apoptosis. Here, we show that therapeutic combination of the lipoxygenase inhibitor MK886 and TRAIL-secreting human mesenchymal stem cells (MSC-TRAIL) provide targeted and prolonged delivery of TRAIL both in vitro and in orthotopic mouse models of glioma. Treatment of either TRAIL-sensitive or TRAIL-resistant human glioma cells with MK886 and MSC-TRAIL resulted in significantly enhanced apoptosis compared with each agent alone. MK886 effectively increased the sensitivity to TRAIL-induced apoptosis via upregulation of the death receptor 5 and downregulation of the antiapoptotic protein survivin in human glioma cell lines and in primary glioma cells. This regulation was accompanied by a substantial increase in caspase activation after combined treatment. Furthermore, in vivo survival experiments and imaging analysis in orthotopic xenografted mice showed that MSC-based TRAIL gene delivery combined with MK886 into the tumors had greater therapeutic efficacy than single-agent treatment. Together, our findings indicate that MK886 combined with MSC-based TRAIL gene delivery may represent a novel strategy for improving the treatment of malignant gliomas. Cancer Res; 72(18); 4807–17. ©2012 AACR.
Data from Clinicopathological Features of Homologous Recombination–Deficient Epithelial Ovarian Cancers: Sensitivity to PARP Inhibitors, Platinum, and Survival
Authors: Mukhopadhyay Asima , Plummer Elizabeth R. , Elattar Ahmed , Soohoo San , Uzir Bisha , Quinn Jennifer E. , McCluggage W. Glenn , Maxwell Perry , Aneke Harriet , Curtin Nicola J. , Edmondson Richard J.
Published: March 2024

Abstract
Up to 50% of epithelial ovarian cancers (EOC) display defects in the homologous recombination (HR) pathway. We sought to determine the ramifications of the homologous recombination–deficient (HRD) status on the clinicopathologic features, chemotherapy response, and survival outcomes of patients with EOCs. HR status was determined in primary cultures from ascitic fluid in 50 chemotherapy-naïve patients by a functional RAD51 immunofluorescence assay and correlated with in vitro sensitivity to the PARP inhibitor (PARPi), rucaparib. All patients went on to receive platinum-based chemotherapy; platinum sensitivity, tumor progression, and overall survival were compared prospectively in HR-competent versus HRD patients. Compared with HR-competent patients, the HRD group was predominantly serous with a higher median CA125 at presentation. HRD was associated with higher ex vivo PARPi sensitivity and clinical platinum sensitivity. Median follow-up duration was 14 months; patients in the HRD group had lower tumor progression rates at 6 months, lower overall/disease-specific death rates at 12 months, and higher median survival. We therefore suggest that HRD as predicted by a functional RAD51 assay correlates with in vitro PARPi sensitivity, clinical platinum sensitivity, and improved survival outcome. Cancer Res; 72(22); 5675–82. ©2012 AACR.
Data from Cyclin D1 Activity Regulates Autophagy and Senescence in the Mammary Epithelium
Authors: Brown Nelson E. , Jeselsohn Rinath , Bihani Teeru , Hu Miaofen G. , Foltopoulou Parthena , Kuperwasser Charlotte , Hinds Philip W.
Published: March 2024

Abstract
Overexpression of cyclin D1 is believed to endow mammary epithelial cells (MEC) with a proliferative advantage by virtue of its contribution to pRB inactivation. Accordingly, abrogation of the kinase-dependent function of cyclin D1 is sufficient to render mice resistant to breast cancer initiated by ErbB2. Here, we report that mouse cyclin D1KE/KE MECs (deficient in cyclin D1 activity) upregulate an autophagy-like process but fail to implement ErbB2-induced senescence in vivo. In addition, immortalized cyclin D1KE/KE MECs retain high rates of autophagy and reduced ErbB2-mediated transformation in vitro. However, highlighting its dual role during tumorigenesis, downregulation of autophagy led to an increase in senescence in cyclin D1KE/KE MECs. Autophagy upregulation was also confirmed in human mammary epithelial cells (HMEC) subjected to genetic and pharmacologic inhibition of cyclin D1 activity and, similar to our murine system, simultaneous inhibition of Cdk4/6 and autophagy in HMECs enhanced the senescence response. Collectively, our findings suggest a previously unrecognized function of cyclin D1 in suppressing autophagy in the mammary epithelium. Cancer Res; 72(24); 6477–89. ©2012 AACR.
Data from Hepatocyte–Stellate Cell Cross-Talk in the Liver Engenders a Permissive Inflammatory Microenvironment That Drives Progression in Hepatocellular Carcinoma
Authors: Coulouarn Cédric , Corlu Anne , Glaise Denise , Guénon Isabelle , Thorgeirsson Snorri S. , Clément Bruno
Published: March 2024

Abstract
Many solid malignant tumors arise on a background of inflamed and/or fibrotic tissues, features that are found in more than 80% hepatocellular carcinomas (HCC). Activated hepatic stellate cells (HSC) play a critical role in fibrogenesis associated with HCC onset and progression, yet their functional impact on hepatocyte fate remains largely unexplored. Here, we used a coculture model to investigate the cross-talk between hepatocytes (human hepatoma cells) and activated human HSCs. Unsupervised genome-wide expression profiling showed that hepatocyte–HSC cross-talk is bidirectional and results in the deregulation of functionally relevant gene networks. Notably, coculturing increased the expression of proinflammatory cytokines and modified the phenotype of hepatocytes toward motile cells. Hepatocyte–HSC cross-talk also generated a permissive proangiogenic microenvironment, particularly by inducing VEGFA and matrix metalloproteinase (MMP)9 expression in HSCs. An integrative genomic analysis revealed that the expression of genes associated with hepatocyte–HSC cross-talk correlated with HCC progression in mice and was predictive of a poor prognosis and metastasis propensity in human HCCs. Interestingly, the effects of cross-talk on migration and angiogenesis were reversed by the histone deacetylase inhibitor trichostatin A. Our findings, therefore, indicate that the cross-talk between hepatoma cells and activated HSCs is an important feature of HCC progression, which may be targeted by epigenetic modulation. Cancer Res; 72(10); 2533–42. ©2012 AACR.
Data from ZNF217 Is a Marker of Poor Prognosis in Breast Cancer That Drives Epithelial–Mesenchymal Transition and Invasion
Authors: Vendrell Julie A. , Thollet Aurélie , Nguyen Nhan T. , Ghayad Sandra E. , Vinot Stéphanie , Bièche Ivan , Grisard Evelyne , Josserand Véronique , Coll Jean-Luc , Roux Pierre , Corbo Laura , Treilleux Isabelle , Rimokh Ruth , Cohen Pascale A.
Published: March 2024

Abstract
The Krüppel-like zinc finger protein ZNF217 is a candidate oncogene in breast cancer. In this study, we showed that high levels of expression of ZNF217 mRNA are associated with poor prognosis and the development of metastases in breast cancer. Overexpression of ZNF217 in breast cancer cells stimulated migration and invasion in vitro and promoted the development of spontaneous lung or node metastases in mice in vivo. ZNF217 also promoted epithelial–mesenchymal transition (EMT) in human mammary epithelial cells, and the TGF-β–activated Smad signaling pathway was identified as a major driver of ZNF217-induced EMT. In addition, a TGF-β autocrine loop sustained activation of the TGF-β pathway in ZNF217-overexpressing mammary epithelial cells, most likely because of ZNF217-mediated direct upregulation of TGFB2 or TGFB3. Inhibition of the TGF-β pathway led to the reversal of ZNF217-mediated EMT. Together, our findings indicate that ZNF217 mRNA expression may represent a novel prognostic biomarker in breast cancer. Therapeutic targeting of ZNF217 of the TGF-β signaling pathway may benefit the subset of patients whose tumors express high levels of ZNF217. Cancer Res; 72(14); 3593–606. ©2012 AACR.
Data from Prohibitin Attenuates Colitis-Associated Tumorigenesis in Mice by Modulating p53 and STAT3 Apoptotic Responses
Authors: Kathiria Arwa S. , Neumann William L. , Rhees Jennifer , Hotchkiss Erin , Cheng Yulan , Genta Robert M. , Meltzer Stephen J. , Souza Rhonda F. , Theiss Arianne L.
Published: March 2024

Abstract
Although inflammatory bowel disease is associated with higher risk of colorectal cancer, the precise pathogenic mechanisms underlying this association are not completely understood. Prohibitin 1 (PHB), a protein implicated in the regulation of proliferation, apoptosis, and transcription, is decreased in intestinal inflammation. In this study, we have established a key function for PHB in mediating colitis-associated cancer. Wild-type and transgenic (Tg) mice specifically overexpressing PHB in intestinal epithelial cells were subjected to a classical two-stage protocol of colitis-associated carcinogenesis. In addition, wild-type and p53 null human cell models were used to assess PHB interaction with STAT3 and p53. Wild-type mice exhibited decreased mucosal PHB protein expression during colitis-associated carcinogenesis. Tg mice exhibited decreased susceptibility in a manner associated with increased apoptosis, p53, Bax, and Bad expression plus decreased Bcl-xL and Bcl-2 expression. PHB overexpression in wild-type but not p53 null human cells increased expression of Bax, Bad, and caspase-3 cleavage. In wild-type p53 cells, PHB overexpression decreased basal and interleukin-6-induced STAT3 activation and expression of the STAT3 responsive genes Bcl-xL and Bcl-2. PHB coimmunoprecipitated with phospho-STAT3 in addition to p53 in cultured cell lysates and colon mucosa. This is the first study to show interaction between PHB and STAT3 in vivo. In summary, our findings suggest that PHB protects against colitis-associated cancer by modulating p53- and STAT3-mediated apoptosis. Modulation of PHB expression in intestinal epithelial cells may offer a potential therapeutic approach to prevent colitis-associated carcinogenesis. Cancer Res; 72(22); 5778–89. ©2012 AACR.
Data from Intracellular ATP Levels Are a Pivotal Determinant of Chemoresistance in Colon Cancer Cells
Authors: Zhou Yunfei , Tozzi Federico , Chen Jinyu , Fan Fan , Xia Ling , Wang Jinrong , Gao Guang , Zhang Aijun , Xia Xuefeng , Brasher Heather , Widger William , Ellis Lee M. , Weihua Zhang
Published: March 2024

Abstract
Altered metabolism in cancer cells is suspected to contribute to chemoresistance, but the precise mechanisms are unclear. Here, we show that intracellular ATP levels are a core determinant in the development of acquired cross-drug resistance of human colon cancer cells that harbor different genetic backgrounds. Drug-resistant cells were characterized by defective mitochondrial ATP production, elevated aerobic glycolysis, higher absolute levels of intracellular ATP, and enhanced HIF-1α–mediated signaling. Interestingly, direct delivery of ATP into cross-chemoresistant cells destabilized HIF-1α and inhibited glycolysis. Thus, drug-resistant cells exhibit a greater “ATP debt” defined as the extra amount of ATP needed to maintain homeostasis of survival pathways under genotoxic stress. Direct delivery of ATP was sufficient to render drug-sensitive cells drug resistant. Conversely, depleting ATP by cell treatment with an inhibitor of glycolysis, 3-bromopyruvate, was sufficient to sensitize cells cross-resistant to multiple chemotherapeutic drugs. In revealing that intracellular ATP levels are a core determinant of chemoresistance in colon cancer cells, our findings may offer a foundation for new improvements to colon cancer treatment. Cancer Res; 72(1); 304–14. ©2011 AACR.
Data from In Vivo Imaging of Drug-Induced Mitochondrial Outer Membrane Permeabilization at Single-Cell Resolution
Authors: Earley Sarah , Vinegoni Claudio , Dunham Joshua , Gorbatov Rostic , Feruglio Paolo Fumene , Weissleder Ralph
Published: March 2024

Abstract
Observing drug responses in the tumor microenvironment in vivo can be technically challenging. As a result, cellular responses to molecularly targeted cancer drugs are often studied in cell culture, which does not accurately represent the behavior of cancer cells growing in vivo. Using high-resolution microscopy and fluorescently labeled genetic reporters for apoptosis, we developed an approach to visualize drug-induced cell death at single-cell resolution in vivo. Stable expression of the mitochondrial intermembrane protein IMS-RP was established in human breast and pancreatic cancer cells. Image analysis was then used to quantify release of IMS-RP into the cytoplasm upon apoptosis and irreversible mitochondrial permeabilization. Both breast and pancreatic cancer cells showed higher basal apoptotic rates in vivo than in culture. To study drug-induced apoptosis, we exposed tumor cells to navitoclax (ABT-263), an inhibitor of Bcl-2, Bcl-xL, and Bcl-w, both in vitro and in vivo. Although the tumors responded to Bcl-2 inhibition in vivo, inducing apoptosis in around 20% of cancer cells, the observed response was much higher in cell culture. Together, our findings show an imaging technique that can be used to directly visualize cell death within the tumor microenvironment in response to drug treatment. Cancer Res; 72(12); 2949–56. ©2012 AACR.
Data from High-Throughput RNAi Screening Reveals Novel Regulators of Telomerase
Authors: Cerone Maria Antonietta , Burgess Darren J , Naceur-Lombardelli Cristina , Lord Christopher J. , Ashworth Alan
Published: March 2024

Abstract
Telomerase is considered an attractive anticancer target on the basis of its common and specific activation in most human cancers. While direct telomerase inhibition is being explored as a therapeutic strategy, alternative strategies to target regulators of telomerase that could disrupt telomere maintenance and cancer cell proliferation are not yet available. Here, we report the findings of a high-throughput functional RNA interference screen to globally profile the contribution of kinases to telomerase activity (TA). This analysis identified a number of novel telomerase modulators, including ERK8 kinase, whose inhibition reduces TA and elicited characteristics of telomere dysfunction. Given that kinases represent attractive drug targets, we addressed the therapeutic implications of our findings, such as demonstrating how limiting TA via kinase blockade could sensitize cells to inhibition of the telomere-associated protein tankyrase. Taken together, our findings suggest novel combinatorial approaches to targeting telomere maintenance as a strategy for cancer therapy. Cancer Res; 71(9); 3328–40. ©2011 AACR.