bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from A Small-Molecule Blocking Ribonucleotide Reductase Holoenzyme Formation Inhibits Cancer Cell Growth and Overcomes Drug Resistance
Authors: Zhou Bingsen , Su Leila , Hu Shuya , Hu Weidong , Yip M.L. Richard , Wu Jun , Gaur Shikha , Smith D. Lynne , Yuan Yate-Ching , Synold Timothy W. , Horne David , Yen Yun
Published: March 2024

Abstract
Ribonucleotide reductase (RNR) is an attractive target for anticancer agents given its central function in DNA synthesis, growth, metastasis, and drug resistance of cancer cells. The current clinically established RNR inhibitors have the shortcomings of short half-life, drug resistance, and iron chelation. Here, we report the development of a novel class of effective RNR inhibitors addressing these issues. A novel ligand-binding pocket on the RNR small subunit (RRM2) near the C-terminal tail was proposed by computer modeling and verified by site-directed mutagenesis and nuclear magnetic resonance (NMR) techniques. A compound targeting this pocket was identified by virtual screening of the National Cancer Institute (NCI) diverse small-molecule database. By lead optimization, we developed the novel RNR inhibitor COH29 that acted as a potent inhibitor of both recombinant and cellular human RNR enzymes. COH29 overcame hydroxyurea and gemcitabine resistance in cancer cells. It effectively inhibited proliferation of most cell lines in the NCI 60 human cancer panel, most notably ovarian cancer and leukemia, but exerted little effect on normal fibroblasts or endothelial cells. In mouse xenograft models of human cancer, COH29 treatment reduced tumor growth compared with vehicle. Site-directed mutagenesis, NMR, and surface plasmon resonance biosensor studies confirmed COH29 binding to the proposed ligand-binding pocket and offered evidence for assembly blockade of the RRM1-RRM2 quaternary structure. Our findings offer preclinical validation of COH29 as a promising new class of RNR inhibitors with a new mechanism of inhibition, with broad potential for improved treatment of human cancer. Cancer Res; 73(21); 6484–93. ©2013 AACR.
Data from Superior Penetration and Retention Behavior of 50 nm Gold Nanoparticles in Tumors
Authors: Huo Shuaidong , Ma Huili , Huang Keyang , Liu Juan , Wei Tuo , Jin Shubin , Zhang Jinchao , He Shengtai , Liang Xing-Jie
Published: March 2024

Abstract
Nanoparticles offer potential as drug delivery systems for chemotherapeutics based on certain advantages of molecular drugs. In this study, we report that particle size exerts great influence on the penetration and retention behavior of nanoparticles entering tumors. On comparing gold-coated Au@tiopronin nanoparticles that were prepared with identical coating and surface properties, we found that 50 nanoparticles were more effective in all in vitro, ex vivo, and in vivo assays conducted using MCF-7 breast cells as a model system. Beyond superior penetration in cultured cell monolayers, 50 nm Au@tiopronin nanoparticles also penetrated more deeply into tumor spheroids ex vivo and accumulated more effectively in tumor xenografts in vivo after a single intravenous dose. In contrast, larger gold-coated nanoparticles were primarily localized in the periphery of the tumor spheroid and around blood vessels, hindering deep penetration into tumors. We found multicellular spheroids to offer a simple ex vivo tumor model to simulate tumor tissue for screening the nanoparticle penetration behavior. Taken together, our findings define an optimal smaller size for nanoparticles that maximizes their effective accumulation in tumor tissue. Cancer Res; 73(1); 319–30. ©2012 AACR.
Data from ABL Regulation by AXL Promotes Cisplatin Resistance in Esophageal Cancer
Authors: Hong Jun , Peng DunFa , Chen Zheng , Sehdev Vikas , Belkhiri Abbes
Published: March 2024

Abstract
Esophageal adenocarcinoma (EAC) is characterized by resistance to chemotherapy and poor outcome. Although cisplatin (CDDP) has been used as a first-line therapy in patients with EAC, resistance remains a major clinical problem. The AXL receptor tyrosine kinase, originally isolated as a transforming gene from leukemia, is overexpressed in several solid tumors. Herein, we assessed AXL protein expression in human EACs and examined its role in CDDP resistance in human EAC cells. AXL overexpression was detected in more than 50% of tumors examined. Elevating AXL in nonoverexpressing cells doubled the CDDP IC50 and increased cell survival three-fold, while attenuating AXL in overexpressing cells reduced survival two-fold. The effects of AXL modulation on cell survival were associated with changes in cellular and molecular markers of apoptosis. Mechanistic investigations revealed that AXL blocked CDDP-induced activation of endogenous p73β (TP73), reducing its protein half-life, and inhibited CDDP-induced levels of p-c-ABL(Y412) and p-p73β(Y99). These changes were associated with a disruption of c-ABL/p73β protein interactions due to association with c-ABL in the cytoplasm, thereby blocking nuclear accumulation of c-ABL and phosphorylation of p73β in response to DNA damage. Together, our results establish that AXL promotes CDDP resistance in esophageal adenocarcinoma and argue that therapeutic targeting of AXL may sensitize these cancers to DNA-damaging drugs. Cancer Res; 73(1); 331–40. ©2012 AACR.
Data from Myoferlin Is a Key Regulator of EGFR Activity in Breast Cancer
Authors: Turtoi Andrei , Blomme Arnaud , Bellahcène Akeila , Gilles Christine , Hennequière Vincent , Peixoto Paul , Bianchi Elettra , Noel Agnès , De Pauw Edwin , Lifrange Eric , Delvenne Philippe , Castronovo Vincent
Published: March 2024

Abstract
Myoferlin is a member of the ferlin family of proteins that participate in plasma membrane fusion, repair, and endocytosis. While some reports have implicated myoferlin in cancer, the extent of its expression in and contributions to cancer are not well established. In this study, we show that myoferlin is overexpressed in human breast cancers and that it has a critical role in controlling degradation of the epidermal growth factor (EGF) receptor (EGFR) after its activation and internalization in breast cancer cells. Myoferlin depletion blocked EGF-induced cell migration and epithelial-to-mesenchymal transition. Both effects were induced as a result of impaired degradation of phosphorylated EGFR via dysfunctional plasma membrane caveolae and alteration of caveolin homo-oligomerization. In parallel, myoferlin depletion reduced tumor development in a chicken chorioallantoic membrane xenograft model of human breast cancer. Considering the therapeutic significance of EGFR targeting, our findings identify myoferlin as a novel candidate function to target for future drug development. Cancer Res; 73(17); 5438–48. ©2013 AACR.
Data from A Synthetic Lethality–Based Strategy to Treat Cancers Harboring a Genetic Deficiency in the Chromatin Remodeling Factor BRG1
Authors: Oike Takahiro , Ogiwara Hideaki , Tominaga Yuichi , Ito Kentaro , Ando Osamu , Tsuta Koji , Mizukami Tatsuji , Shimada Yoko , Isomura Hisanori , Komachi Mayumi , Furuta Koh , Watanabe Shun-Ichi , Nakano Takashi , Yokota Jun , Kohno Takashi
Published: March 2024

Abstract
The occurrence of inactivating mutations in SWI/SNF chromatin-remodeling genes in common cancers has attracted a great deal of interest. However, mechanistic strategies to target tumor cells carrying such mutations are yet to be developed. This study proposes a synthetic-lethality therapy for treating cancers deficient in the SWI/SNF catalytic (ATPase) subunit, BRG1/SMARCA4. The strategy relies upon inhibition of BRM/SMARCA2, another catalytic SWI/SNF subunit with a BRG1-related activity. Immunohistochemical analysis of a cohort of non–small-cell lung carcinomas (NSCLC) indicated that 15.5% (16 of 103) of the cohort, corresponding to preferentially undifferentiated tumors, was deficient in BRG1 expression. All BRG1-deficient cases were negative for alterations in known therapeutic target genes, for example, EGFR and DDR2 gene mutations, ALK gene fusions, or FGFR1 gene amplifications. RNA interference (RNAi)–mediated silencing of BRM suppressed the growth of BRG1-deficient cancer cells relative to BRG1-proficient cancer cells, inducing senescence via activation of p21/CDKN1A. This growth suppression was reversed by transduction of wild-type but not ATPase-deficient BRG1. In support of these in vitro results, a conditional RNAi study conducted in vivo revealed that BRM depletion suppressed the growth of BRG1-deficient tumor xenografts. Our results offer a rationale to develop BRM-ATPase inhibitors as a strategy to treat BRG1/SMARCA4–deficient cancers, including NSCLCs that lack mutations in presently known therapeutic target genes. Cancer Res; 73(17); 5508–18. ©2013 AACR.
Data from Obesity Promotes Breast Cancer by CCL2-Mediated Macrophage Recruitment and Angiogenesis
Authors: Arendt Lisa M. , McCready Jessica , Keller Patricia J. , Baker Dana D. , Naber Stephen P. , Seewaldt Victoria , Kuperwasser Charlotte
Published: March 2024

Abstract
Obesity is one of the most important preventable causes of cancer and the most significant risk factor for breast cancer in postmenopausal women. Compared with lean women, obese women are more likely to be diagnosed with a larger, higher grade tumor, an increased incidence of lymph node metastases, and elevated risk of distant recurrence. However, the mechanisms connecting obesity to the pathogenesis of breast cancer are poorly defined. Here, we show that during obesity, adipocytes within human and mouse breast tissues recruit and activate macrophages through a previously uncharacterized CCL2/IL-1β/CXCL12 signaling pathway. Activated macrophages in turn promote stromal vascularization and angiogenesis even before the formation of cancer. Recapitulating these changes using a novel humanized breast cancer model was sufficient to promote angiogenesis and prime the microenvironment prior to neoplastic transformation for accelerated breast oncogenesis. These findings provide a mechanistic role for adipocytes and macrophages before carcinogenesis that may be critical for prevention and treatment of obesity-related cancer. Cancer Res; 73(19); 6080–93. ©2013 AACR.
Data from Novel Modeling of Cancer Cell Signaling Pathways Enables Systematic Drug Repositioning for Distinct Breast Cancer Metastases
Authors: Zhao Hong , Jin Guangxu , Cui Kemi , Ren Ding , Liu Timothy , Chen Peikai , Wong Solomon , Li Fuhai , Fan Yubo , Rodriguez Angel , Chang Jenny , Wong Stephen TC
Published: March 2024

Abstract
A new type of signaling network element, called cancer signaling bridges (CSB), has been shown to have the potential for systematic and fast-tracked drug repositioning. On the basis of CSBs, we developed a computational model to derive specific downstream signaling pathways that reveal previously unknown target–disease connections and new mechanisms for specific cancer subtypes. The model enables us to reposition drugs based on available patient gene expression data. We applied this model to repurpose known or shelved drugs for brain, lung, and bone metastases of breast cancer with the hypothesis that cancer subtypes have their own specific signaling mechanisms. To test the hypothesis, we addressed specific CSBs for each metastasis that satisfy (i) CSB proteins are activated by the maximal number of enriched signaling pathways specific to a given metastasis, and (ii) CSB proteins are involved in the most differential expressed coding genes specific to each breast cancer metastasis. The identified signaling networks for the three types of breast cancer metastases contain 31, 15, and 18 proteins and are used to reposition 15, 9, and 2 drug candidates for the brain, lung, and bone metastases. We conducted both in vitro and in vivo preclinical experiments as well as analysis on patient tumor specimens to evaluate the targets and repositioned drugs. Of special note, we found that the Food and Drug Administration-approved drugs, sunitinib and dasatinib, prohibit brain metastases derived from breast cancer, addressing one particularly challenging aspect of this disease. Cancer Res; 73(20); 6149–63. ©2013 AACR.
Data from miR-153 Supports Colorectal Cancer Progression via Pleiotropic Effects That Enhance Invasion and Chemotherapeutic Resistance
Authors: Zhang Lei , Pickard Karen , Jenei Veronika , Bullock Marc D. , Bruce Amanda , Mitter Richard , Kelly Gavin , Paraskeva Christos , Strefford John , Primrose John , Thomas Gareth J. , Packham Graham , Mirnezami Alex H.
Published: March 2024

Abstract
Although microRNAs (miRNA) have been broadly studied in cancer, comparatively less is understood about their role in progression. Here we report that miR-153 has a dual role during progression of colorectal cancer by enhancing cellular invasiveness and platinum-based chemotherapy resistance. miRNA profiling revealed that miR-153 was highly expressed in a cellular model of advanced stage colorectal cancer. Its upregulation was also noted in primary human colorectal cancer compared with normal colonic epithelium and in more advanced colorectal cancer stages compared with early stage disease. In colorectal cancer patients followed for 50 months, 21 of 30 patients with high levels of miR-153 had disease progression compared with others in this group with low levels of miR-153. Functional studies revealed that miR-153 upregulation increased colorectal cancer invasiveness and resistance to oxaliplatin and cisplatin both in vitro and in vivo. Mechanistic investigations indicated that miR-153 promoted invasiveness indirectly by inducing matrix metalloprotease enzyme 9 production, whereas drug resistance was mediated directly by inhibiting the Forkhead transcription factor Forkhead box O3a (FOXO3a). In support of the latter finding, we found that levels of miR-153 and FOXO3a were inversely correlated in matched human colorectal cancer specimens. Our findings establish key roles for miR-153 overexpression in colorectal cancer progression, rationalizing therapeutic strategies to target expression of this miRNA for colorectal cancer treatment. Cancer Res; 73(21); 6435–47. ©2013 AACR.
Data from Booster Vaccinations against Cancer Are Critical in Prophylactic but Detrimental in Therapeutic Settings
Authors: Ricupito Alessia , Grioni Matteo , Calcinotto Arianna , Hess Michelini Rodrigo , Longhi Renato , Mondino Anna , Bellone Matteo
Published: March 2024

Abstract
Although cancer vaccines are in the clinic, several issues remain to be addressed to increase vaccine efficacy. In particular, whether how and how frequently a patient should be boosted remains to be defined. Here, we have assessed the ability of dendritic cell (DC)-based vaccines to induce a long-lasting tumor-specific CTL response in either prophylactic or therapeutic settings by taking advantage of transplantable and spontaneous mouse tumor models. Implementing a 24-hour ex vivo intracellular cytokine production assay, we have found that priming with a DC-based vaccine induced a long-lasting CTL response in wild-type mice, and homologous boosting better sustained the pool of central memory T cells, which associated with potent protection against B16F1 melanoma challenge. Appropriate timing of booster vaccination was also critical, as a tight boosting schedule hindered persistence of IFN-γ–competent memory CD8+ T cells and mice survival in prophylactic settings. Conversely, prime/boost vaccination proved to be of no advantage or even detrimental in therapeutic settings in B16F1 and transgenic adenocarcinoma of the mouse prostate (TRAMP) models, respectively. Although DC priming was indeed needed for tumor shrinkage, restoration of immune competence, and prolonged survival of TRAMP mice, repeated boosting did not sustain the pool of central memory CTLs and was detrimental for mice overall survival. Thus, our results indicate that booster vaccinations impact antitumor immunity to different extents, depending on their prophylactic or therapeutic administration, and suggest evaluating the need for boosting in any given patient with cancer depending on the state of the disease. Cancer Res; 73(12); 3545–54. ©2013 AACR.
Data from Vaccination for Invasive Canine Meningioma Induces In Situ Production of Antibodies Capable of Antibody-Dependent Cell-Mediated Cytotoxicity
Authors: Andersen Brian M. , Pluhar G. Elizabeth , Seiler Charles E. , Goulart Michelle R. , SantaCruz Karen S. , Schutten Melissa M. , Meints Joyce P. , O'Sullivan M. Gerard , Bentley R. Timothy , Packer Rebecca A. , Thomovsky Stephanie A. , Chen Annie V. , Faissler Dominik , Chen Wei , Hunt Matthew A. , Olin Michael R. , Ohlfest John R.
Published: March 2024

Abstract
Malignant and atypical meningiomas are resistant to standard therapies and associated with poor prognosis. Despite progress in the treatment of other tumors with therapeutic vaccines, this approach has not been tested preclinically or clinically in these tumors. Spontaneous canine meningioma is a clinically meaningful but underutilized model for preclinical testing of novel strategies for aggressive human meningioma. We treated 11 meningioma-bearing dogs with surgery and vaccine immunotherapy consisting of autologous tumor cell lysate combined with toll-like receptor ligands. Therapy was well tolerated, and only one dog had tumor growth that required intervention, with a mean follow up of 585 days. IFN-γ–elaborating T cells were detected in the peripheral blood of 2 cases, but vaccine-induced tumor-reactive antibody responses developed in all dogs. Antibody responses were polyclonal, recognizing both intracellular and cell surface antigens, and HSP60 was identified as one common antigen. Tumor-reactive antibodies bound allogeneic canine and human meningiomas, showing common antigens across breed and species. Histologic analysis revealed robust infiltration of antibody-secreting plasma cells into the brain around the tumor in posttreatment compared with pretreatment samples. Tumor-reactive antibodies were capable of inducing antibody-dependent cell-mediated cytotoxicity to autologous and allogeneic tumor cells. These data show the feasibility and immunologic efficacy of vaccine immunotherapy for a large animal model of human meningioma and warrant further development toward human trials. Cancer Res; 73(10); 2987–97. ©2013 AACR.
Data from Akt SUMOylation Regulates Cell Proliferation and Tumorigenesis
Authors: Li Rong , Wei Jie , Jiang Cong , Liu Dongmei , Deng Lu , Zhang Kai , Wang Ping
Published: March 2024

Abstract
Proto-oncogene Akt plays essential roles in cell proliferation and tumorigenesis. Full activation of Akt is regulated by phosphorylation, ubiquitination, and acetylation. Here we report that SUMOylation of Akt is a novel mechanism for its activation. Systematically analyzing the role of lysine residues in Akt activation revealed that K276, which is located in a SUMOylation consensus motif, is essential for Akt activation. Ectopic or endogenous Akt1 could be modified by SUMOylation. RNA interference–mediated silencing of UBC9 reduced Akt SUMOylation, which was promoted by SUMO E3 ligase PIAS1 and reversed by the SUMO-specific protease SENP1. Although multiple sites on Akt could be SUMOylated, K276 was identified as a major SUMO acceptor site. K276R or E278A mutation reduced SUMOylation of Akt but had little effect on its ubiquitination. Strikingly, these mutations also completely abolished Akt kinase activity. In support of these results, we found that expression of PIAS1 and SUMO1 increased Akt activity, whereas expression of SENP1 reduced Akt1 activity. Interestingly, the cancer-derived mutant E17K in Akt1 that occurs in various cancers was more efficiently SUMOylated than wild-type Akt. Moreover, SUMOylation loss dramatically reduced Akt1 E17K–mediated cell proliferation, cell migration, and tumorigenesis. Collectively, our findings establish that Akt SUMOylation provides a novel regulatory mechanism for activating Akt function. Cancer Res; 73(18); 5742–53. ©2013 AACR.
Data from Nkx2-8 Downregulation Promotes Angiogenesis and Activates NF-κB in Esophageal Cancer
Authors: Lin Chuyong , Song Libing , Gong Hui , Liu Aibin , Lin Xi , Wu Jueheng , Li Mengfeng , Li Jun
Published: March 2024

Abstract
Angiogenesis is a major clinical feature of esophageal squamous cell carcinoma (ESCC), an aggressive disease of increasing incidence in developed countries. In ESCCs, the proangiogenic factor VEGF-C is an independent prognostic factor for ESCC, where understanding the mechanisms of VEGF-C upregulation may cue possible therapeutic insights. Here, we report that expression of the transcription factor Nkx2-8 is downregulated in ESCCs where it inversely correlates with progression and VEGF-C upregulation. Patients with ESCCs with lower Nkx2-8 expression exhibited reduced overall survival. Modulating expression of Nkx2-8 up or down inhibited or enhanced, respectively, proangiogenic activity in vitro and in vivo. Mechanistic investigations showed that Nkx2-8 repressed NF-κB activity by restraining nuclear localization of NF-κB p65 via downregulation of AKIP1, a NF-κB p65 binding partner, and also by directly targeting the AKIP1 promoter. We confirmed evidence for the importance of the Nkx2-8/AKIP1/NF-κB axis identified in ESCC cell models through an immunohistochemical analysis of a large cohort of human ESCC specimens. Taken together, our results showed that Nkx2-8 functions as a tumor suppressor in ESCCs, the downregulation of which contributes to NF-κB activation and ESCC angiogenesis. Cancer Res; 73(12); 3638–48. ©2013 AACR.
Data from Glutathione-Deficient Mice Have Increased Sensitivity to Transplacental Benzo[a]pyrene-Induced Premature Ovarian Failure and Ovarian Tumorigenesis
Authors: Lim Jinhwan , Lawson Gregory W. , Nakamura Brooke N. , Ortiz Laura , Hur Jin A. , Kavanagh Terrance J. , Luderer Ulrike
Published: March 2024

Abstract
Polycyclic aromatic hydrocarbons (PAH) such as benzo[a]pyrene (BaP) are ubiquitous environmental pollutants found in tobacco smoke, air pollution, and grilled foods. Prenatal exposure to BaP causes premature reproductive senescence in mice, and other PAHs are transplacental ovarian carcinogens. Glutathione (GSH) is critical for detoxification of the reactive metabolites of PAHs. Therefore, we hypothesized that mice that are genetically deficient in GSH synthesis, due to deletion of the modifier subunit of glutamate cysteine ligase (Gclm), the rate-limiting enzyme in GSH synthesis, have increased destruction of oogonia, premature ovarian failure, and ovarian tumorigenesis after transplacental BaP exposure compared with Gclm+/+ females. Gclm+/− female and male mice were mated, and dams were treated with 0, 2, or 10 mg/kg/d BaP in sesame oil by gavage from gestational days 7 to 16. Compared with oil-treated F1 females of the same genotype, Gclm−/− prenatally BaP-treated females had significantly greater decrements in offspring production than Gclm+/+ BaP-treated females. Similarly, we observed significant BaP dose × Gclm genotype interactions on ovarian follicle counts and ovarian tumor multiplicity at 7.5 months of age, with Gclm−/− females having greater decrements in follicle numbers and more ovarian tumors in response to prenatal BaP exposure than Gclm+/+ females. The ovarian tumors were positive for the epithelial marker cytokeratin. Our results show that prenatal exposure of females to BaP causes premature ovarian failure and ovarian tumorigenesis and that embryonic GSH deficiency due to deletion of Gclm increases sensitivity to these transplacental ovarian effects of BaP. Cancer Res; 73(2); 908–17. ©2012 AACR.
Data from Hsp27 Regulates Epithelial Mesenchymal Transition, Metastasis, and Circulating Tumor Cells in Prostate Cancer
Authors: Shiota Masaki , Bishop Jennifer L. , Nip Ka Mun , Zardan Anousheh , Takeuchi Ario , Cordonnier Thomas , Beraldi Eliana , Bazov Jenny , Fazli Ladan , Chi Kim , Gleave Martin , Zoubeidi Amina
Published: March 2024

Abstract
Defining the mechanisms underlying metastatic progression of prostate cancer may lead to insights into how to decrease morbidity and mortality in this disease. An important determinant of metastasis is epithelial-to-mesenchymal transition (EMT), and the mechanisms that control the process of EMT in cancer cells are still emerging. Here, we report that the molecular chaperone Hsp27 (HSPB1) drives EMT in prostate cancer, whereas its attenuation reverses EMT and decreases cell migration, invasion, and matrix metalloproteinase activity. Mechanistically, silencing Hsp27 decreased IL-6–dependent STAT3 phosphorylation, nuclear translocation, and STAT3 binding to the Twist promoter, suggesting that Hsp27 is required for IL-6–mediated EMT via modulation of STAT3/Twist signaling. We observed a correlation between Hsp27 and Twist in patients with prostate cancer, with Hsp27 and Twist expression each elevated in high-grade prostate cancer tumors. Hsp27 inhibition by OGX-427, an antisense therapy currently in phase II trials, reduced tumor metastasis in a murine model of prostate cancer. More importantly, OGX-427 treatment decreased the number of circulating tumor cells in patients with metastatic castration-resistant prostate cancer in a phase I clinical trial. Overall, this study defines Hsp27 as a critical regulator of IL-6–dependent and IL-6–independent EMT, validating this chaperone as a therapeutic target to treat metastatic prostate cancer. Cancer Res; 73(10); 3109–19. ©2013 AACR.
Data from Characterization of Rearrangements Involving the ALK Gene Reveals a Novel Truncated Form Associated with Tumor Aggressiveness in Neuroblastoma
Authors: Cazes Alex , Louis-Brennetot Caroline , Mazot Pierre , Dingli Florent , Lombard Bérangère , Boeva Valentina , Daveau Romain , Cappo Julie , Combaret Valérie , Schleiermacher Gudrun , Jouannet Stéphanie , Ferrand Sandrine , Pierron Gaëlle , Barillot Emmanuel , Loew Damarys , Vigny Marc , Delattre Olivier , Janoueix-Lerosey Isabelle
Published: March 2024

Abstract
Activating mutations of the ALK gene have been identified in sporadic and familial cases of neuroblastoma (NB), a cancer of the peripheral nervous system, and are thought to be the primary mechanism of oncogenic activation of this receptor in this pediatric neoplasm. To address the possibility that ALK activation may occur through genomic rearrangements as detected in other cancers, we first took advantage of high-resolution array-comparative genomic hybridization to search for ALK rearrangements in NB samples. Using complementary experiments by capture/paired-end sequencing and FISH experiments, various types of rearrangements were fully characterized, including partial gains or amplifications, in several NB cell lines and primary tumors. In the CLB-Bar cell line, we described a genomic rearrangement associated with an amplification of the ALK locus, leading to the expression of a 170 kDa protein lacking part of the extracellular domain encoded by exons 4 to 11, named ALKΔ4-11. Analysis of genomic DNA from the tumor at diagnosis and relapse revealed that the ALK gene was amplified at diagnosis but that the rearranged ALK allele was observed at the relapse stage only, suggesting that it may be implicated in tumor aggressiveness. Consistently, oncogenic and tumorigenic properties of the ALKΔ4-11 variant were shown after stable expression in NIH3T3 cells. Moreover, we documented an increased constitutive kinase activity of this variant, as well as an impaired maturation and retention into intracellular compartments. These results indicate that genomic rearrangements constitute an alternative mechanism to ALK point mutations resulting in receptor activation. Cancer Res; 73(1); 195–204. ©2012 AACR.
Data from Combined Targeting of PDK1 and EGFR Triggers Regression of Glioblastoma by Reversing the Warburg Effect
Authors: Velpula Kiran Kumar , Bhasin Arnima , Asuthkar Swapna , Tsung Andrew J.
Published: March 2024

Abstract
Glioblastoma multiforme is the most aggressive primary brain tumor in adults. Overexpression of the EGF receptor (EGFR) is recognized as a widespread oncogenic signature in glioblastoma multiforme, but the complexity of its contributions is not fully understood, nor the most effective ways to leverage anti-EGFR therapy in this setting. Hypoxia is known to drive the aggressive character of glioblastoma multiforme by promoting aerobic glycolysis rather than pyruvate oxidation carried out in mitochondria (OXPHOS), a phenomenon termed the Warburg effect, which is a general feature of oncogenesis. In this study, we report that hypoxia drives expression of the pyruvate dehydrogenase kinase (PDK1) and EGFR along with the hypoxia-inducing factor (HIF)-1α in human glioblastoma multiforme cells. PDK1 is a HIF-1–regulated gene and our findings indicated that hypoxia-induced PDK1 expression may promote EGFR activation, initiating a feed-forward loop that can sustain malignant progression. RNAi-mediated attenuation of PDK1 and EGFR lowered PDK1-EGFR activation and decreased HIF-1α expression, shifting the Warburg phenotype to OXPHOS and inhibiting glioblastoma multiforme growth and proliferation. In clinical specimens of glioblastoma multiforme, we found that immunohistochemical expression of PDK1, EGFR, and HIF-1α were elevated in glioblastoma multiforme specimens when compared with normal brain tissues. Collectively, our studies establish PDK1 as a key driver and candidate therapeutic target in glioblastoma multiforme. Cancer Res; 73(24); 7277–89. ©2013 AACR.
Data from Tumor Cells Upregulate Normoxic HIF-1α in Response to Doxorubicin
Authors: Cao Yiting , Eble Joseph M. , Moon Ejung , Yuan Hong , Weitzel Douglas H. , Landon Chelsea D. , Yu-Chih Nien Charleen , Hanna Gabi , Rich Jeremy N. , Provenzale James M. , Dewhirst Mark W.
Published: March 2024

Abstract
Hypoxia-inducible factor 1 (HIF-1) is a master transcription factor that controls cellular homeostasis. Although its activation benefits normal tissue, HIF-1 activation in tumors is a major risk factor for angiogenesis, therapeutic resistance, and poor prognosis. HIF-1 activity is usually suppressed under normoxic conditions because of rapid oxygen-dependent degradation of HIF-1α. Here, we show that, under normoxic conditions, HIF-1α is upregulated in tumor cells in response to doxorubicin, a chemotherapeutic agent used to treat many cancers. In addition, doxorubicin enhanced VEGF secretion by normoxic tumor cells and stimulated tumor angiogenesis. Doxorubicin-induced accumulation of HIF-1α in normoxic cells was caused by increased expression and activation of STAT1, the activation of which stimulated expression of iNOS and its synthesis of nitric oxide (NO) in tumor cells. Mechanistic investigations established that blocking NO synthesis or STAT1 activation was sufficient to attenuate the HIF-1α accumulation induced by doxorubicin in normoxic cancer cells. To our knowledge, this is the first report that a chemotherapeutic drug can induce HIF-1α accumulation in normoxic cells, an efficacy-limiting activity. Our results argue that HIF-1α-targeting strategies may enhance doxorubicin efficacy. More generally, they suggest a broader perspective on the design of combination chemotherapy approaches with immediate clinical impact. Cancer Res; 73(20); 6230–42. ©2013 AACR.
Data from EGFR/JIP-4/JNK2 Signaling Attenuates Cetuximab-Mediated Radiosensitization of Squamous Cell Carcinoma Cells
Authors: Eke Iris , Schneider Lydia , Förster Claudia , Zips Daniel , Kunz-Schughart Leoni A. , Cordes Nils
Published: March 2024

Abstract
EGF receptor (EGFR) promotes tumor growth as well as radio- and chemoresistance in various human malignancies including squamous cell carcinomas (SCC). In addition to deactivation of prosurvival signaling, cetuximab-mediated EGFR targeting might concomitantly induce self-attenuating signaling bypasses. Identification of such bypass mechanisms is key to improve the efficacy of targeted approaches. Here, we show great similarity of EGFR signaling and radiation survival in cetuximab-treated SCC cells grown in a more physiologic three-dimensional extracellular matrix and as tumor xenografts in contrast to conventional monolayer cell cultures. Using phosphoproteome arrays, we observed strong induction of JNK2 phosphorylation potentially resulting from cetuximab-inhibited EGFR through c-jun-NH2-kinase (JNK)-interacting protein-4 (JIP-4), which was identified using an immunoprecipitation-mass spectrometric approach. Inhibition of this signaling bypass by JIP-4 or JNK2 knockdown or pharmacologic JNK2 inhibition enhanced cetuximab efficacy and tumor cell radiosensitivity. Our findings add new facets to EGFR signaling and indicate signaling bypass possibilities of cancer cells to improve their survival on cetuximab treatment. By deactivation of cetuximab–self-attenuating JNK2-dependent signaling, the cytotoxicity, and radiosensitizing potential of cetuximab can be augmented. Cancer Res; 73(1); 297–306. ©2012 AACR.
Data from Cytotoxic Activity of Tivantinib (ARQ 197) Is Not Due Solely to c-MET Inhibition
Authors: Katayama Ryohei , Aoyama Aki , Yamori Takao , Qi Jie , Oh-hara Tomoko , Song Youngchul , Engelman Jeffrey A. , Fujita Naoya
Published: March 2024

Abstract
The receptor tyrosine kinase c-MET is the high-affinity receptor for the hepatocyte growth factor (HGF). The HGF/c-MET axis is often dysregulated in tumors. c-MET activation can be caused by MET gene amplification, activating mutations, and auto- or paracrine mechanisms. Thus, c-MET inhibitors are under development as anticancer drugs. Tivantinib (ARQ 197) was reported as a small-molecule c-MET inhibitor and early clinical studies suggest antitumor activity. To assess whether the antitumor activity of tivantinib was due to inhibition of c-MET, we compared the activity of tivantinib with other c-MET inhibitors in both c-MET–addicted and nonaddicted cancer cells. As expected, other c-MET inhibitors, crizotinib and PHA-665752, suppressed the growth of c-MET-addicted cancers, but not the growth of cancers that are not addicted to c-MET. In contrast, tivantinib inhibited cell viability with similar potency in both c-MET-addicted and nonaddicted cells. These results suggest that tivantinib exhibits its antitumor activity in a manner independent of c-MET status. Tivantinib treatment induced a G2–M cell-cycle arrest in EBC1 cells similarly to vincristine treatment, whereas PHA-665752 or crizotinib treatment markedly induced G0–G1 cell-cycle arrest. To identify the additional molecular target of tivantinib, we conducted COMPARE analysis, an in silico screening of a database of drug sensitivities across 39 cancer cell lines (JFCR39), and identified microtubule as a target of tivantinib. Tivantinib-treated cells showed typical microtubule disruption similar to vincristine and inhibited microtubule assembly in vitro. These results suggest that tivantinib inhibits microtubule polymerization in addition to inhibiting c-MET. Cancer Res; 73(10); 3087–96. ©2013 AACR.
Data from CD95L Cell Surface Cleavage Triggers a Prometastatic Signaling Pathway in Triple-Negative Breast Cancer
Authors: Malleter Marine , Tauzin Sébastien , Bessede Alban , Castellano Rémy , Goubard Armelle , Godey Florence , Levêque Jean , Jézéquel Pascal , Campion Loic , Campone Mario , Ducret Thomas , MacGrogan Gaëtan , Debure Laure , Collette Yves , Vacher Pierre , Legembre Patrick
Published: March 2024

Abstract
Triple-negative breast cancers (TNBC) lacking estrogen and progesterone receptors and HER2 amplification have a relatively high risk of metastatic dissemination, but the mechanistic basis for this risk is not understood. Here, we report that serum levels of CD95 ligand (CD95L) are higher in patients with TNBC than in other patients with breast cancer. Metalloprotease-mediated cleavage of CD95L expressed by endothelial cells surrounding tumors generates a gradient that promotes cell motility due to the formation of an unconventional CD95-containing receptosome called the motility-inducing signaling complex. The formation of this complex was instrumental for Nox3-driven reactive oxygen species generation. Mechanistic investigations revealed a Yes–Orai1–EGFR–PI3K pathway that triggered migration of TNBC cells exposed to CD95L. Our findings establish a prometastatic function for metalloprotease-cleaved CD95L in TNBCs, revisiting its role in carcinogenesis. Cancer Res; 73(22); 6711–21. ©2013 AACR.
Data from Immune Infiltrates Are Prognostic Factors in Localized Gastrointestinal Stromal Tumors
Authors: Rusakiewicz Sylvie , Semeraro Michaela , Sarabi Matthieu , Desbois Mélanie , Locher Clara , Mendez Rosa , Vimond Nadège , Concha Angel , Garrido Federico , Isambert Nicolas , Chaigneau Loic , Le Brun-Ly Valérie , Dubreuil Patrice , Cremer Isabelle , Caignard Anne , Poirier-Colame Vichnou , Chaba Kariman , Flament Caroline , Halama Niels , Jäger Dirk , Eggermont Alexander , Bonvalot Sylvie , Commo Frédéric , Terrier Philippe , Opolon Paule , Emile Jean-François , Coindre Jean-Michel , Kroemer Guido , Chaput Nathalie , Le Cesne Axel , Blay Jean-Yves , Zitvogel Laurence
Published: March 2024

Abstract
Cancer immunosurveillance relies on effector/memory tumor-infiltrating CD8+ T cells with a T-helper cell 1 (TH1) profile. Evidence for a natural killer (NK) cell-based control of human malignancies is still largely missing. The KIT tyrosine kinase inhibitor imatinib mesylate markedly prolongs the survival of patients with gastrointestinal stromal tumors (GIST) by direct effects on tumor cells as well as by indirect immunostimulatory effects on T and NK cells. Here, we investigated the prognostic value of tumor-infiltrating lymphocytes (TIL) expressing CD3, Foxp3, or NKp46 (NCR1) in a cohort of patients with localized GIST. We found that CD3+ TIL were highly activated in GIST and were especially enriched in areas of the tumor that conserve class I MHC expression despite imatinib mesylate treatment. High densities of CD3+ TIL predicted progression-free survival (PFS) in multivariate analyses. Moreover, GIST were infiltrated by a homogeneous subset of cytokine-secreting CD56bright (NCAM1) NK cells that accumulated in tumor foci after imatinib mesylate treatment. The density of the NK infiltrate independently predicted PFS and added prognostic information to the Miettinen score, as well as to the KIT mutational status. NK and T lymphocytes preferentially distributed to distinct areas of tumor sections and probably contributed independently to GIST immunosurveillance. These findings encourage the prospective validation of immune biomarkers for optimal risk stratification of patients with GIST. Cancer Res; 73(12); 3499–510. ©2013 AACR.
Data from Sox2 Requirement in Sonic Hedgehog-Associated Medulloblastoma
Authors: Ahlfeld Julia , Favaro Rebecca , Pagella Pierfrancesco , Kretzschmar Hans A. , Nicolis Silvia , Schüller Ulrich
Published: March 2024

Abstract
The transcription factor Sox2 has been shown to play essential roles during embryonic development as well as in cancer. To more precisely understand tumor biology and to identify potential therapeutical targets, we thoroughly investigated the expression and function of Sox2 in medulloblastoma, a malignant embryonic brain tumor that initiates in the posterior fossa and eventually spreads throughout the entire cerebrospinal axis. We examined a large series of tumor samples (n = 188) to show that SOX2 is specifically expressed in Sonic hedgehog (SHH)-associated medulloblastoma with an interesting preponderance in adolescent and adult cases. We further show that cerebellar granule neuron precursors (CGNP), which are believed to serve as the cell of origin for this medulloblastoma subgroup, express Sox2 in early stages. Also, Shh-associated medulloblastoma can be initiated from such Sox2-positive CGNPs in mice. Independent of their endogenous Sox2 expression, constitutive activation of Shh signaling in CGNPs resulted in significantly enhanced proliferation and ectopic expression of Sox2 in vitro and Sox2-positive medulloblastoma in vivo. Genetic ablation of Sox2 from murine medulloblastoma did not affect survival, most likely due to a compensatory overexpression of Sox3. However, acute deletion of Sox2 from primary cultures of CGNPs with constitutive Shh signaling significantly decreased proliferation, whereas overexpression of Sox2 enhanced proliferation of murine medulloblastoma cells. We conclude that Sox2 is a marker for Shh-dependent medulloblastomas where it is required and sufficient to drive tumor cell proliferation. Cancer Res; 73(12); 3796–807. ©2013 AACR.
Data from C-RAF Mutations Confer Resistance to RAF Inhibitors
Authors: Antony Rajee , Emery Caroline M. , Sawyer Allison M. , Garraway Levi A.
Published: March 2024

Abstract
Melanomas that contain B-RAFV600E mutations respond transiently to RAF and MEK inhibitors; however, resistance to these agents remains a formidable challenge. Although B- or C-RAF dysregulation represents prominent resistance mechanisms, resistance-associated point mutations in RAF oncoproteins are surprisingly rare. To gain insights herein, we conducted random mutagenesis screens to identify B- or C-RAF mutations that confer resistance to RAF inhibitors. Whereas bona fide B-RAFV600E resistance alleles were rarely observed, we identified multiple C-RAF mutations that produced biochemical and pharmacologic resistance. Potent C-RAF resistance alleles localized to a 14-3-3 consensus binding site or a separate site within the P loop. These mutations elicited paradoxical upregulation of RAF kinase activity in a dimerization-dependent manner following exposure to RAF inhibitors. Knowledge of resistance-associated C-RAF mutations may enhance biochemical understanding of RAF-dependent signaling, anticipate clinical resistance to novel RAF inhibitors, and guide the design of “next-generation” inhibitors for deployment in RAF- or RAS-driven malignancies. Cancer Res; 73(15); 4840–51. ©2013 AACR.
Data from Microtubule-Associated Histone Deacetylase 6 Supports the Calcium Store Sensor STIM1 in Mediating Malignant Cell Behaviors
Authors: Chen Ying-Ting , Chen Yih-Fung , Chiu Wen-Tai , Liu Kuan-Yu , Liu Yu-Lin , Chang Jang-Yang , Chang Hsien-Chang , Shen Meng-Ru
Published: March 2024

Abstract
Stromal-interaction molecule 1 (STIM1) is an endoplasmic reticulum Ca2+ storage sensor that promotes cell growth, migration, and angiogenesis in breast and cervical cancers. Here, we report that the microtubule-associated histone deacetylase 6 (HDAC6) differentially regulates activation of STIM1-mediated store-operated Ca2+ entry (SOCE) between cervical cancer cells and normal cervical epithelial cells. Confocal microscopy of living cells indicated that microtubule integrity was necessary for STIM1 trafficking to the plasma membrane and interaction with Orai1, an essential pore subunit of SOCE. Cancer cells overexpressed both STIM1 and Orai1 compared with normal cervical epithelial cells. HDAC6 upregulation in cancer cells was accompanied by hypoacetylated α-tubulin. Tubastatin-A, a specific HDAC6 inhibitor, inhibited STIM1 translocation to plasma membrane and blocked SOCE activation in cancer cells but not normal epithelial cells. Genetic or pharmacologic inhibition of HDAC6 blocked STIM1 membrane trafficking and downstream Ca2+ influx, as evidenced by total internal reflection fluorescent images and intracellular Ca2+ determination. In contrast, HDAC6 inhibition did not affect interactions between STIM1 and the microtubule plus end-binding protein EB1. Analysis of surgical specimens confirmed that most cervical cancer tissues overexpressed STIM1 and Orai1, accompanied by hypoacetylated α-tubulin. Together, our results identify HDAC6 as a candidate target to disrupt STIM1-mediated SOCE as a general strategy to block malignant cell behavior. Cancer Res; 73(14); 4500–9. ©2013 AACR.
Data from miRNA-95 Mediates Radioresistance in Tumors by Targeting the Sphingolipid Phosphatase SGPP1
Authors: Huang Xiaoyong , Taeb Samira , Jahangiri Sahar , Emmenegger Urban , Tran Elisa , Bruce Jeff , Mesci Aruz , Korpela Elina , Vesprini Danny , Wong C. Shun , Bristow Robert G. , Liu Fei-Fei , Liu Stanley K.
Published: March 2024

Abstract
Radiation resistance poses a major clinical challenge in cancer treatment, but little is known about how microRNA (miR) may regulate this phenomenon. In this study, we used next-generation sequencing to perform an unbiased comparison of miR expression in PC3 prostate cancer cells rendered resistant to fractionated radiation treatment. One miR candidate found to be upregulated by ionizing radiation was miR-95, the enforced expression of which promoted radiation resistance in a variety of cancer cells. miR-95 overexpression recapitulated an aggressive phenotype including increased cellular proliferation, deregulated G2–M checkpoint following ionizing radiation, and increased invasive potential. Using combined in silico prediction and microarray expression analyses, we identified and validated the sphingolipid phosphatase SGPP1, an antagonist of sphingosine-1-phosphate signaling, as a target of miR-95 that promotes radiation resistance. Consistent with this finding, cell treatment with FTY720, a clinically approved small molecule inhibitor of S1P signaling, sensitized miR-95 overexpressing cells to radiation treatment. In vivo assays extended the significance of these results, showing that miR-95 overexpression increased tumor growth and resistance to radiation treatment in tumor xenografts. Furthermore, reduced tumor necrosis and increased cellular proliferation were seen after radiation treatment of miR-95 overexpressing tumors compared with control tumors. Finally, miR-95 expression was increased in human prostate and breast cancer specimens compared with normal tissue. Together, our work reveals miR-95 expression as a critical determinant of radiation resistance in cancer cells. Cancer Res; 73(23); 6972–86. ©2013 AACR.
Data from A Transcriptional and Metabolic Signature of Primary Aneuploidy Is Present in Chromosomally Unstable Cancer Cells and Informs Clinical Prognosis
Authors: Sheltzer Jason M.
Published: March 2024

Abstract
Aneuploidy is invariably associated with poor proliferation of primary cells, but the specific contributions of abnormal karyotypes to cancer, a disease characterized by aneuploidy and dysregulated proliferation, remain unclear. In this study, I demonstrate that the transcriptional alterations caused by aneuploidy in primary cells are also present in chromosomally unstable cancer cell lines, but the same alterations are not common to all aneuploid cancers. Chromosomally unstable cancer lines and aneuploid primary cells also share an increase in glycolytic and TCA cycle flux. The biological response to aneuploidy is associated with cellular stress and slow proliferation, and a 70-gene signature derived from primary aneuploid cells was defined as a strong predictor of increased survival in several cancers. Inversely, a transcriptional signature derived from clonal aneuploidy in tumors correlated with high mitotic activity and poor prognosis. Together, these findings suggested that there are two types of aneuploidy in cancer: one is clonal aneuploidy, which is selected during tumor evolution and associated with robust growth, and the other is subclonal aneuploidy caused by chromosomal instability (CIN). Subclonal aneuploidy more closely resembles the stressed state of primary aneuploid cells, yet CIN is not benign; a subset of genes upregulated in high-CIN cancers predict aggressive disease in human patients in a proliferation-independent manner. Cancer Res; 73(21); 6401–12. ©2013 AACR.