bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from β-Lapachone Micellar Nanotherapeutics for Non–Small Cell Lung Cancer Therapy
Authors: Blanco Elvin , Bey Erik A. , Khemtong Chalermchai , Yang Su-Geun , Setti-Guthi Jagadeesh , Chen Huabing , Kessinger Chase W. , Carnevale Kevin A. , Bornmann William G. , Boothman David A. , Gao Jinming
Published: March 2024

Abstract
Lung cancer is the leading cause of cancer-related deaths with current chemotherapies lacking adequate specificity and efficacy. β-Lapachone (β-lap) is a novel anticancer drug that is bioactivated by NAD(P)H:quinone oxidoreductase 1, an enzyme found specifically overexpressed in non–small cell lung cancer (NSCLC). Herein, we report a nanotherapeutic strategy that targets NSCLC tumors in two ways: (a) pharmacodynamically through the use of a bioactivatable agent, β-lap, and (b) pharmacokinetically by using a biocompatible nanocarrier, polymeric micelles, to achieve drug stability, bioavailability, and targeted delivery. β-Lap micelles produced by a film sonication technique were small (∼30 nm), displayed core-shell architecture, and possessed favorable release kinetics. Pharmacokinetic analyses in mice bearing subcutaneous A549 lung tumors showed prolonged blood circulation (t1/2, ∼28 h) and increased accumulation in tumors. Antitumor efficacy analyses in mice bearing subcutaneous A549 lung tumors and orthotopic Lewis lung carcinoma models showed significant tumor growth delay and increased survival. In summary, we have established a clinically viable β-lap nanomedicine platform with enhanced safety, pharmacokinetics, and antitumor efficacy for the specific treatment of NSCLC tumors. Cancer Res; 70(10); 3896–904. ©2010 AACR.
Data from The Insulin-like Growth Factor-1 Receptor–Targeting Antibody, CP-751,871, Suppresses Tumor-Derived VEGF and Synergizes with Rapamycin in Models of Childhood Sarcoma
Authors: Kurmasheva Raushan T. , Dudkin Lorina , Billups Catherine , Debelenko Larisa V. , Morton Christopher L. , Houghton Peter J.
Published: March 2024

Abstract
Signaling through the type 1 insulin-like growth factor receptor (IGF-1R) occurs in many human cancers, including childhood sarcomas. As a consequence, targeting the IGF-1R has become a focus for cancer drug development. We examined the antitumor activity of CP-751,871, a human antibody that blocks IGF-1R ligand binding, alone and in combination with rapamycin against sarcoma cell lines in vitro and xenograft models in vivo. In Ewing sarcoma (EWS) cell lines, CP751,871 inhibited growth poorly (<50%), but prevented rapamycin-induced hyperphosphorylation of AKT(Ser473) and induced greater than additive apoptosis. Rapamycin treatment also increased secretion of IGF-1 resulting in phosphorylation of IGF-1R (Tyr1131) that was blocked by CP751,871. In vivo CP-751,871, rapamycin, or the combination were evaluated against EWS, osteosarcoma, and rhabdomyosarcoma xenografts. CP751871 induced significant growth inhibition [EFS(T/C) >2] in four models. Rapamycin induced significant growth inhibition [EFS(T/C) >2] in nine models. Although neither agent given alone caused tumor regressions, in combination, these agents had greater than additive activity against 5 of 13 xenografts and induced complete remissions in one model each of rhabdomyosarcoma and EWS, and in three of four osteosarcoma models. CP751,871 caused complete IGF-1R down-regulation, suppression of AKT phosphorylation, and dramatically suppressed tumor-derived vascular endothelial growth factor (VEGF) in some sarcoma xenografts. Rapamycin treatment did not markedly suppress VEGF in tumors and synergized only in tumor lines where VEGF was dramatically inhibited by CP751,871. These data suggest a model in which blockade of IGF-1R suppresses tumor-derived VEGF to a level where rapamycin can effectively suppress the response in vascular endothelial cells. [Cancer Res 2009;69(19):7662–71]
Data from Mutant p53 Disrupts the Stress MAPK Activation Circuit Induced by ASK1-Dependent Stabilization of Daxx
Authors: Kitamura Tetsuya , Fukuyo Yayoi , Inoue Masahiro , Horikoshi Nobuko T. , Shindoh Masanobu , Rogers Buck E. , Usheva Anny , Horikoshi Nobuo
Published: March 2024

Abstract
Daxx is a regulatory protein for apoptosis signal–regulating kinase 1 (ASK1) which activates c-Jun NH2-terminal kinase (JNK) and p38 pathways in response to stressors such as tumor necrosis factor-α (TNFα). Here, we show that TNFα treatment induces the accumulation of Daxx protein through ASK1 activation by preventing its proteasome-dependent degradation. ASK1 directly phosphorylates Daxx at Ser176 and Ser184 and Daxx is required for the sustained activation of JNK. Tumorigenic mutant p53, which binds to Daxx and inhibits Daxx-dependent activation of ASK1, prevents Daxx phosphorylation and stabilization. When mutant p53 was depleted in cancer cells, Daxx was accumulated and the cell-killing effect of TNFα was restored. Our results indicate that Daxx not only activates ASK1 but also is a downstream target of ASK1 and that accumulated Daxx further activates ASK1. Thus, the Daxx-ASK1 positive feedback loop amplifying JNK/p38 signaling plays an important role in the cell-killing effects of stressors, such as TNFα. Tumorigenic mutant p53 disrupts this circuit and makes cells more tolerable to stresses, as its gain-of-function mechanism. [Cancer Res 2009;69(19):7681–8]
Data from Functional Genetic Polymorphisms in the Aromatase Gene CYP19 Vary the Response of Breast Cancer Patients to Neoadjuvant Therapy with Aromatase Inhibitors
Authors: Wang Liewei , Ellsworth Katarzyna A. , Moon Irene , Pelleymounter Linda L. , Eckloff Bruce W. , Martin Yvette N. , Fridley Brooke L. , Jenkins Gregory D. , Batzler Anthony , Suman Vera J. , Ravi Saranya , Dixon J. Michael , Miller William R. , Wieben Eric D. , Buzdar Aman , Weinshilboum Richard M. , Ingle James N.
Published: March 2024

Abstract
Aromatase (CYP19) is a critical enzyme in estrogen biosynthesis and aromatase inhibitors (AI) are employed widely for endocrine therapy in postmenopausal women with breast cancer. We hypothesized that single nucleotide polymorphisms (SNPs) in the CYP19 gene may alter the effectiveness of AI therapy in the neoadjuvant setting. Genomic DNA was obtained for sequencing from 52 women pre-AI and post-AI treatment in this setting. Additionally, genomic DNA obtained from 82 samples of breast cancer and 19 samples of normal breast tissue was subjected to resequencing. No differences in CYP19 sequence were observed between tumor and germ-line DNA in the same patient. A total of 48 SNPs were identified including 4 novel SNPs when compared with previous resequencing data. For genotype-phenotype association studies, we determined the levels of aromatase activity, estrone, estradiol, and tumor size in patients pre-AI and post-AI treatment. We defined two tightly linked SNPs (rs6493497 and rs7176005 in the 5'-flanking region of CYP19 exon 1.1) that were significantly associated with a greater change in aromatase activity after AI treatment. In a follow-up study of 200 women with early-stage breast cancer who were treated with adjuvant anastrozole, these same two SNPs were also associated with higher plasma estradiol levels in patients pre-AI and post-AI treatment. Electrophoretic mobility shift and reporter gene assays confirmed likely functional effects of these two SNPs on transcription of CYP19. Our findings indicate that two common genetic polymorphisms in the aromatase gene CYP19 vary the response of breast cancer patients to aromatase inhibitors. Cancer Res; 70(1); 319–28
Data from Presence of a Putative Tumor-Initiating Progenitor Cell Population Predicts Poor Prognosis in Smokers with Non–Small Cell Lung Cancer
Authors: Ooi Aik T. , Mah Vei , Nickerson Derek W. , Gilbert Jennifer L. , Ha Vi Luan , Hegab Ahmed E. , Horvath Steve , Alavi Mohammad , Maresh Erin L. , Chia David , Gower Adam C. , Lenburg Marc E. , Spira Avrum , Solis Luisa M. , Wistuba Ignacio I. , Walser Tonya C. , Wallace William D. , Dubinett Steven M. , Goodglick Lee , Gomperts Brigitte N.
Published: March 2024

Abstract
Smoking is the most important known risk factor for the development of lung cancer. Tobacco exposure results in chronic inflammation, tissue injury, and repair. A recent hypothesis argues for a stem/progenitor cell involved in airway epithelial repair that may be a tumor-initiating cell in lung cancer and which may be associated with recurrence and metastasis. We used immunostaining, quantitative real-time PCR, Western blots, and lung cancer tissue microarrays to identify subpopulations of airway epithelial stem/progenitor cells under steady-state conditions, normal repair, aberrant repair with premalignant lesions and lung cancer, and their correlation with injury and prognosis. We identified a population of keratin 14 (K14)–expressing progenitor epithelial cells that was involved in repair after injury. Dysregulated repair resulted in the persistence of K14+ cells in the airway epithelium in potentially premalignant lesions. The presence of K14+ progenitor airway epithelial cells in NSCLC predicted a poor prognosis, and this predictive value was strongest in smokers, in which it also correlated with metastasis. This suggests that reparative K14+ progenitor cells may be tumor-initiating cells in this subgroup of smokers with NSCLC. Cancer Res; 70(16); 6639–48. ©2010 AACR.
Data from Altered Runx1 Subnuclear Targeting Enhances Myeloid Cell Proliferation and Blocks Differentiation by Activating a miR-24/MKP-7/MAPK Network
Authors: Zaidi Sayyed K. , Dowdy Christopher R. , van Wijnen Andre J. , Lian Jane B. , Raza Azra , Stein Janet L. , Croce Carlo M. , Stein Gary S.
Published: March 2024

Abstract
Disruption of Runx1/AML1 subnuclear localization, either by a single amino acid substitution or by a chromosomal translocation [e.g., t(8;21)], is linked to the etiology of acute myeloid leukemia (AML). Here, we show that this defect induces a select set of micro-RNAs (miR) in myeloid progenitor cells and AML patients with t(8;21). Both Runx1 and the t(8;21)-encoded AML1-ETO occupy the miR-24-23-27 locus and reciprocally control miR-24 transcription. miR-24 directly downregulates mitogen-activated protein kinase (MAPK) phosphatase-7 and enhances phosphorylation of both c-jun-NH2-kinase and p38 kinases. Expression of miR-24 stimulates myeloid cell growth, renders proliferation independent of interleukin-3, and blocks granulocytic differentiation. Thus, compromised Runx1 function induces a miR-dependent mechanism that, through MAPK signaling, enhances myeloid proliferation but blocks differentiation—key steps that contribute to leukemia. [Cancer Res 2009;69(21):8249–55]
Data from Breast Cancer Dormancy Can Be Maintained by Small Numbers of Micrometastases
Authors: Willis Lisa , Alarcón Tomas , Elia George , Jones J. Louise , Wright Nick A. , Tomlinson Ian P.M. , Graham Trevor A. , Page Karen M.
Published: March 2024

Abstract
Late relapse of breast cancer can occur more than 25 years after primary diagnosis. During the intervening years between initial treatment and relapse, occult cancers are maintained in an apparent state of dormancy that is poorly understood. In this study, we applied a probabilistic mathematical model to long-term follow-up studies of postresection patients to investigate the factors involved in mediating breast cancer dormancy. Our results suggest that long-term dormancy is maintained most often by just one growth-restricted dangerous micrometastasis. Analysis of the empirical data by Approximate Bayesian Computation indicated that patients in dormancy have between 1 and 5 micrometastases at 10 years postresection, when they escape growth restriction with a half-life of <69 years and are >0.4 mm in diameter. Before resection, primary tumors seed at most an average of 6 dangerous micrometastases that escape from growth restriction with a half-life of at least 12 years. Our findings suggest that effective preventive treatments will need to eliminate these small numbers of micrometastases, which may be preangiogenic and nonvascularized until they switch to growth due to one oncogenic mutation or tumor suppressor gene inactivation. In summary, breast cancer dormancy seems to be maintained by small numbers of sizeable micrometastases that escape from growth restriction with a half-life exceeding 12 years. Cancer Res; 70(11); 4310–7. ©2010 AACR.
Data from βIII-Tubulin Is a Multifunctional Protein Involved in Drug Sensitivity and Tumorigenesis in Non–Small Cell Lung Cancer
Authors: McCarroll Joshua A. , Gan Pei Pei , Liu Marjorie , Kavallaris Maria
Published: March 2024

Abstract
Advanced non–small cell lung cancer (NSCLC) has a dismal prognosis. βIII-Tubulin, a protein highly expressed in neuronal cells, is strongly associated with drug-refractory and aggressive NSCLC. To date, the role of this protein in in vivo drug resistance and tumorigenesis has not been determined. NSCLC cells stably expressing βIII-tubulin short hairpin RNA displayed reduced growth and increased chemotherapy sensitivity when compared with control clones. In concordance with these results, stable suppression of βIII-tubulin reduced the incidence and significantly delayed the growth of tumors in mice relative to controls. Our findings indicate that βIII-tubulin mediates not only drug sensitivity but also the incidence and progression of lung cancer. βIII-Tubulin is a cellular survival factor that, when suppressed, sensitizes cells to chemotherapy via enhanced apoptosis induction and decreased tumorigenesis. Findings establish that upregulation of a neuronal tubulin isotype is a key contributor to tumor progression and drug sensitivity in lung adenocarcinoma. Cancer Res; 70(12); 4995–5003. ©2010 AACR.
Data from The Polycomb Group Protein Bmi-1 Is Essential for the Growth of Multiple Myeloma Cells
Authors: Jagani Zainab , Wiederschain Dmitri , Loo Alice , He Dan , Mosher Rebecca , Fordjour Paul , Monahan John , Morrissey Michael , Yao Yung-Mae , Lengauer Christoph , Warmuth Markus , Sellers William R. , Dorsch Marion
Published: March 2024

Abstract
Bmi-1 is a member of the Polycomb group family of proteins that function in the epigenetic silencing of genes governing self-renewal, differentiation, and proliferation. Bmi-1 was first identified through its ability to accelerate c-Myc–induced lymphomagenesis. Subsequent studies have further supported an oncogenic role for Bmi-1 in several cancers including those of the breast, lung, prostate, and brain. Using a stable and inducible shRNA system to silence Bmi-1 gene expression, we show a novel role for Bmi-1 in regulating the growth and clonogenic capacity of multiple myeloma cells both in vitro and in vivo. Moreover, to elucidate novel gene targets controlled by Bmi-1, global transcriptional profiling studies were performed in the setting of induced loss of Bmi-1 function. We found that the expression of the proapoptotic gene Bim is negatively regulated by Bmi-1 and that Bim knockdown functionally rescues the apoptotic phenotype induced upon loss of Bmi-1. Therefore, these studies not only highlight Bmi-1 as a cancer-dependent factor in multiple myeloma, but also elucidate a novel antiapoptotic mechanism for Bmi-1 function involving the suppression of Bim. Cancer Res; 70(13); 5528–38. ©2010 AACR.
Data from ΔNp63α Repression of the Notch1 Gene Supports the Proliferative Capacity of Normal Human Keratinocytes and Cervical Cancer Cells
Authors: Yugawa Takashi , Narisawa-Saito Mako , Yoshimatsu Yuki , Haga Kei , Ohno Shin-ichi , Egawa Nagayasu , Fujita Masatoshi , Kiyono Tohru
Published: March 2024

Abstract
The p53 family member p63 is a master regulator of epithelial development. One of its isoforms, ΔNp63α, is predominantly expressed in the basal cells of stratified epithelia and plays a fundamental role in control of regenerative potential and epithelial integrity. In contrast to p53, p63 is rarely mutated in human cancers, but it is frequently overexpressed in squamous cell carcinomas (SCC). However, its functional relevance to tumorigenesis remains largely unclear. We previously identified the Notch1 gene as a novel transcriptional target of p53. Here, we show that ΔNp63α functions as a transcriptional repressor of the Notch1 gene through the p53-responsive element. Knockdown of p63 caused upregulation of Notch1 expression and marked reduction in proliferation and clonogenicity of both normal human keratinocytes and cervical cancer cell lines overexpressing ΔNp63α. Concomitant silencing of Notch1 significantly rescued this phenotype, indicating the growth defect induced by p63 deficiency to be, at least in part, attributable to Notch1 function. Conversely, overexpression of ΔNp63α decreased basal levels of Notch1, increased proliferative potential of normal human keratinocytes, and inhibited both p53-dependent and p53-independent induction of Notch1 and differentiation markers upon genotoxic stress and serum exposure, respectively. These results suggest that ΔNp63α maintains the self-renewing capacity of normal human keratinocytes and cervical cancer cells partly through transcriptional repression of the Notch1 gene and imply a novel pathogenetical significance of frequently observed overexpression of ΔNp63α together with p53 inactivation in SCCs. Cancer Res; 70(10); 4034–44. ©2010 AACR.
Data from Motor Protein–Dependent Membrane Trafficking of KCl Cotransporter-4 Is Important for Cancer Cell Invasion
Authors: Chen Yih-Fung , Chou Cheng-Yang , Wilkins Robert J. , Ellory J. Clive , Mount David B. , Shen Meng-Ru
Published: March 2024

Abstract
The KCl cotransporter (KCC) is a major determinant of osmotic homeostasis and plays an emerging role in tumor biology. This study stresses the important role of KCC4 in tumor malignant behavior. Real-time reverse transcription-PCR on samples collected by laser microdissection and immunofluorescent stainings with different KCC isoform antibodies indicate that KCC4 is abundant in metastatic cervical and ovarian cancer tissues. Insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) stimulate KCC4 recruitment from a presumably inactive cytoplasmic pool of endoplasmic reticulum and Golgi to plasma membrane along actin cytoskeleton that is significantly inhibited by LY294002 and wortmannin. Throughout the trafficking process, KCC4 is incorporated into lipid rafts that function as a platform for the association between KCC4 and myosin Va, an actin-dependent motor protein. KCC4 and ezrin, a membrane cytoskeleton linker, colocalize at lamellipodia of migratory cancer cells. Interference with KCC activity by either an inhibitor or a dominant-negative loss-of-function mutant profoundly suppressed the IGF-I–induced membrane trafficking of KCC4 and the structural interaction between KCC4 and ezrin near the cell surface. Endogenous cancer cell invasiveness was significantly attenuated by small interfering RNA targeting KCC4, and the residual invasiveness was much less sensitive to IGF-I or EGF stimulation. In the metastatic cancer tissues, KCC4 colocalizes with IGF-I or EGF, indicating a likely in vivo stimulation of KCC4 function by growth factors. Thus, blockade of KCC4 trafficking and surface expression may provide a potential target for the prevention of IGF-I– or EGF-dependent cancer spread. [Cancer Res 2009;69(22):8585–93]
Data from Fibroblast Growth Factor Receptor Signaling Dramatically Accelerates Tumorigenesis and Enhances Oncoprotein Translation in the Mouse Mammary Tumor Virus–Wnt-1 Mouse Model of Breast Cancer
Authors: Pond Adam C. , Herschkowitz Jason I. , Schwertfeger Kathryn L. , Welm Bryan , Zhang Yiqun , York Brian , Cardiff Robert D. , Hilsenbeck Susan , Perou Charles M. , Creighton Chad J. , Lloyd Richard E. , Rosen Jeffrey M.
Published: March 2024

Abstract
Fibroblast growth factor (FGF) cooperates with the Wnt/β-catenin pathway to promote mammary tumorigenesis. To investigate the mechanisms involved in FGF/Wnt cooperation, we genetically engineered a model of inducible FGF receptor (iFGFR) signaling in the context of the well-established mouse mammary tumor virus–Wnt-1 transgenic mouse. In the bigenic mice, iFGFR1 activation dramatically enhanced mammary tumorigenesis. Expression microarray analysis did not show transcriptional enhancement of Wnt/β-catenin target genes but instead showed a translational gene signature that also correlated with elevated FGFR1 and FGFR2 in human breast cancer data sets. Additionally, iFGFR1 activation enhanced recruitment of RNA to polysomes, resulting in a marked increase in protein expression of several different Wnt/β-catenin target genes. FGF pathway activation stimulated extracellular signal-regulated kinase and the phosphorylation of key translation regulators both in vivo in the mouse model and in vitro in a human breast cancer cell line. Our results suggest that cooperation of the FGF and Wnt pathways in mammary tumorigenesis is based on the activation of protein translational pathways that result in, but are not limited to, increased expression of Wnt/β-catenin target genes (at the level of protein translation). Further, they reveal protein translation initiation factors as potential therapeutic targets for human breast cancers with alterations in FGF signaling. Cancer Res; 70(12); 4868–79. ©2010 AACR.
Data from Novel Dyskerin-Mediated Mechanism of p53 Inactivation through Defective mRNA Translation
Authors: Montanaro Lorenzo , Calienni Maria , Bertoni Sara , Rocchi Laura , Sansone Pasquale , Storci Gianluca , Santini Donatella , Ceccarelli Claudio , Taffurelli Mario , Carnicelli Domenica , Brigotti Maurizio , Bonafè Massimiliano , Treré Davide , Derenzini Massimo
Published: March 2024

Abstract
In up to 60% of human cancers, p53 gene mutations are responsible for direct inactivation of the tumor suppressor function of p53. Alternative mechanisms of p53 inactivation described thus far mainly affect its posttranslational regulation. In X-linked dyskeratosis congenita, a multisystemic syndrome characterized by increased cancer susceptibility, mutations of the DKC1 gene encoding dyskerin cause a selective defect in the translation of a subgroup of internal ribosome entry site (IRES)–containing cellular mRNAs. In this study, we show that impairment of dyskerin function can cause p53 inactivation due to a defect in p53 mRNA translation. siRNA-mediated reduction of dyskerin levels caused a decrease of p53 mRNA translation, protein levels, and functional activity, both in human breast cancer cells and in primary mammary epithelial progenitor cells. These effects seemed to be independent of the known role of dyskerin in telomerase function, and they were associated with a specific impairment of translation initiation mediated by IRES elements present in p53 mRNA. In a series of human primary breast cancers retaining wild-type p53, we found that low levels of dyskerin expression were associated with reduced expression of p53-positive target genes. Our findings suggest that a dyskerin-mediated mechanism of p53 inactivation may occur in a subset of human tumors. Cancer Res; 70(11); 4767–77. ©2010 AACR.
Data from Myc-Induced MicroRNAs Integrate Myc-Mediated Cell Proliferation and Cell Fate
Authors: Kim Jong Wook , Mori Seiichi , Nevins Joseph R.
Published: March 2024

Abstract
The Myc pathway, often deregulated in cancer, is critical in determining cell fate by coordinating a gene expression program that links the control of cell proliferation with cell fate decisions. As such, precise control of the Myc pathway activity must be achieved to ensure faithful execution of appropriate cellular response and to prevent progressing toward a malignant state. With recent highlighted roles of microRNAs (miRNA) as critical components of gene control, we sought to evaluate the extent to which miRNAs may contribute in the execution of Myc function. Combined analysis of mRNA and miRNA expression profiles reveals an integration whereby the Myc-mediated induction of miRNAs leads to the repression of various mRNAs encoding tumor suppressors that block cell proliferation including p21, p27, and Rb. In addition, the proapoptotic PTEN tumor suppressor gene is also repressed by Myc-induced miRNAs, suggesting that Myc-induced miRNAs contribute to the precise control of a transcriptional program that coordinates the balance of cell proliferation and cell death. Cancer Res; 70(12); 4820–8. ©2010 AACR.
Data from FOXO1A Is a Target for HER2-Overexpressing Breast Tumors
Authors: Wu Yanyuan , Shang Xiying , Sarkissyan Marianna , Slamon Dennis , Vadgama Jaydutt V.
Published: March 2024

Abstract
Trastuzumab treatment has improved the overall survival of HER2-overexpressing breast cancer patients. However, many of these patients will eventually become resistant to treatment. The mechanisms that contribute to resistance to trastuzumab are unknown. In this study, we tested the hypothesis that targeting of the FKHR transcription factor FOXO1A in HER2-overexpressing breast tumor cells can overcome the trastuzumab resistance in vitro. We have shown that overexpression of HER2 leads to activation of phosphatidylinositol 3-kinase (PI3K)/Akt pathway and subsequent inactivation of FOXO1A in HER2-overexpressing breast cancer cells SKBR3, BT474, and MCF7-HER2. In wild-type SKBR3 and BT474 cells, trastuzumab downregulates active Akt and increases FOXO1A expression that leads to increase in p27kip1 and decrease in cyclin D1 and finally inhibits cell proliferation. In contrast, the effect of trastuzumab was eliminated by the reduction of FOXO1A in HER2-overexpressing cells with constitutively active Akt1 (SKBR3/AA28 and BT474/AA9). The downregulation of FOXO1A resulted in nuclear export of p27kip1. Blocking the constitutively active Akt by a specific Akt/protein kinase B signaling inhibitor-2 (API-2) significantly increased FOXO1A expression and rendered the cells more responsive to trastuzumab-induced growth inhibition. Reactivation of FOXO1A by stable or transient transfection also restored the growth-inhibitory effects of trastuzumab in SKBR3/AA28, BT474/AA9, and MCF7-HER2 cells. Knocking down FOXO1A by small interfering RNA resulted in reducing trastuzumab-induced growth inhibition. In summary, trastuzumab can inhibit proliferation of HER2-overexpressing breast cancer cells by reactivating FOXO1A through inhibition of the PI3K/Akt pathway. FOXO1A may therefore serve as a target for HER2-overexpressing breast tumors. Cancer Res; 70(13); 5475–85. ©2010 AACR.
Data from Aurora B–Mediated Phosphorylation of RASSF1A Maintains Proper Cytokinesis by Recruiting Syntaxin16 to the Midzone and Midbody
Authors: Song Su Jung , Kim Soon Jung , Song Min Sup , Lim Dae-Sik
Published: March 2024

Abstract
Aurora B is critically involved in ensuring proper cytokinesis and maintaining genomic stability. The tumor suppressor RASSF1A regulates cell cycle progression by regulating mitotic progression, G1-S transition, and microtubule stability. We previously reported that both Aurora A and Aurora B phosphorylate RASSF1A, and showed that phosphorylation of RASSF1A by Aurora A blocks the inhibitory function of RASSF1A toward anaphase-promoting complex-Cdc20. However, the role of Aurora B–mediated RASSF1A phosphorylation remains unknown. Here, we show that phosphorylation of RASSF1A on Ser203 by Aurora B during late mitosis has a critical role in regulating cytokinesis. Notably, RASSF1A interacts with Syntaxin16, a member of the t-SNARE family, at the midzone and midbody during late mitosis. Aurora B is required for this interaction and for the subsequent recruitment of Syntaxin16 to the midzone and midbody, a prerequisite for the successful completion of cytokinesis. Furthermore, Aurora B depletion results in a failure of Syntaxin16 to properly localize to the midzone and midbody, a mislocalization that was prevented by overexpression of the phosphomimetic RASSF1A (S203D) mutant. Finally, either depletion of Syntaxin16 or expression of the nonphosphorylatable RASSF1A (S203A) mutant results in cytokinesis defects. Our findings implicate Aurora B–mediated phosphorylation of RASSF1A in the regulation of cytokinesis. [Cancer Res 2009;69(22):8540–4]
Data from Confirmation of Linkage to and Localization of Familial Colon Cancer Risk Haplotype on Chromosome 9q22
Authors: Gray-McGuire Courtney , Guda Kishore , Adrianto Indra , Lin Chee Paul , Natale Leanna , Potter John D. , Newcomb Polly , Poole Elizabeth M. , Ulrich Cornelia M. , Lindor Noralane , Goode Ellen L. , Fridley Brooke L. , Jenkins Robert , Le Marchand Loic , Casey Graham , Haile Robert , Hopper John , Jenkins Mark , Young Joanne , Buchanan Daniel , Gallinger Steve , Adams Mark , Lewis Susan , Willis Joseph , Elston Robert , Markowitz Sanford D. , Wiesner Georgia L.
Published: March 2024

Abstract
Genetic risk factors are important contributors to the development of colorectal cancer. Following the definition of a linkage signal at 9q22-31, we fine mapped this region in an independent collection of colon cancer families. We used a custom array of single-nucleotide polymorphisms (SNP) densely spaced across the candidate region, performing both single-SNP and moving-window association analyses to identify a colon neoplasia risk haplotype. Through this approach, we isolated the association effect to a five-SNP haplotype centered at 98.15 Mb on chromosome 9q. This haplotype is in strong linkage disequilibrium with the haplotype block containing HABP4 and may be a surrogate for the effect of this CD30 Ki-1 antigen. It is also in close proximity to GALNT12, also recently shown to be altered in colon tumors. We used a predictive modeling algorithm to show the contribution of this risk haplotype and surrounding candidate genes in distinguishing between colon cancer cases and healthy controls. The ability to replicate this finding, the strength of the haplotype association (odds ratio, 3.68), and the accuracy of our prediction model (∼60%) all strongly support the presence of a locus for familial colon cancer on chromosome 9q. Cancer Res; 70(13); 5409–18. ©2010 AACR.
Data from Aerobic Glycolysis Suppresses p53 Activity to Provide Selective Protection from Apoptosis upon Loss of Growth Signals or Inhibition of BCR-Abl
Authors: Mason Emily F. , Zhao Yuxing , Goraksha-Hicks Pankuri , Coloff Jonathan L. , Gannon Hugh , Jones Stephen N. , Rathmell Jeffrey C.
Published: March 2024

Abstract
Unlike the growth factor dependence of normal cells, cancer cells can maintain growth factor–independent glycolysis and survival through expression of oncogenic kinases, such as BCR-Abl. Although targeted kinase inhibition can promote cancer cell death, therapeutic resistance develops frequently, and further mechanistic understanding is needed. Cell metabolism may be central to this cell death pathway, as we have shown that growth factor deprivation leads to decreased glycolysis that promotes apoptosis via p53 activation and induction of the proapoptotic protein Puma. Here, we extend these findings to show that elevated glucose metabolism, characteristic of cancer cells, can suppress protein kinase Cδ (PKCδ)–dependent p53 activation to maintain cell survival after growth factor withdrawal. In contrast, DNA damage–induced p53 activation was PKCδ independent and was not metabolically sensitive. Both stresses required p53 Ser18 phosphorylation for maximal activity but led to unique patterns of p53 target gene expression, showing distinct activation and response pathways for p53 that were differentially regulated by metabolism. Consistent with oncogenic kinases acting to replace growth factors, treatment of BCR-Abl–expressing cells with the kinase inhibitor imatinib led to reduced metabolism and p53- and Puma-dependent cell death. Accordingly, maintenance of glucose uptake inhibited p53 activation and promoted imatinib resistance. Furthermore, inhibition of glycolysis enhanced imatinib sensitivity in BCR-Abl–expressing cells with wild-type p53 but had little effect on p53-null cells. These data show that distinct pathways regulate p53 after DNA damage and metabolic stress and that inhibiting glucose metabolism may enhance the efficacy of and overcome resistance to targeted molecular cancer therapies. Cancer Res; 70(20); 8066–76. ©2010 AACR.
Data from Superior In vivo Efficacy of Afucosylated Trastuzumab in the Treatment of HER2-Amplified Breast Cancer
Authors: Junttila Teemu T. , Parsons Kathryn , Olsson Christine , Lu Yanmei , Xin Yan , Theriault Julie , Crocker Lisa , Pabonan Oliver , Baginski Tomasz , Meng Gloria , Totpal Klara , Kelley Robert F. , Sliwkowski Mark X.
Published: March 2024

Abstract
The enhancement of immune effector functions has been proposed as a potential strategy for increasing the efficacy of therapeutic antibodies. Here, we show that removing fucose from trastuzumab (Herceptin) increased its binding to FcγRIIIa, enhanced antibody-dependent cell-mediated cytotoxicity, and more than doubled the median progression-free survival when compared with conventional trastuzumab in treating preclinical models of HER2-amplified breast cancer. Our results show that afucosylated trastuzumab has superior efficacy in treating in vivo models of HER2-amplified breast cancer and support the development of effector function–enhanced antibodies for solid tumor therapy. Cancer Res; 70(11); 4481–9. ©2010 AACR.
Data from WNT11 Expression Is Induced by Estrogen-Related Receptor α and β-Catenin and Acts in an Autocrine Manner to Increase Cancer Cell Migration
Authors: Dwyer Mary A. , Joseph James D. , Wade Hilary E. , Eaton Matthew L. , Kunder Rebecca S. , Kazmin Dmitri , Chang Ching-yi , McDonnell Donald P.
Published: March 2024

Abstract
Elevated expression of the orphan nuclear receptor estrogen-related receptor α (ERRα) has been associated with a negative outcome in several cancers, although the mechanism(s) by which this receptor influences the pathophysiology of this disease and how its activity is regulated remain unknown. Using a chemical biology approach, it was determined that compounds, previously shown to inhibit canonical Wnt signaling, also inhibited the transcriptional activity of ERRα. The significance of this association was revealed in a series of biochemical and genetic experiments that show that (a) ERRα, β-catenin (β-cat), and lymphoid enhancer-binding factor-1 form macromolecular complexes in cells, (b) ERRα transcriptional activity is enhanced by β-cat expression and vice versa, and (c) there is a high level of overlap among genes previously shown to be regulated by ERRα or β-cat. Furthermore, silencing of ERRα and β-cat expression individually or together dramatically reduced the migratory capacity of breast, prostate, and colon cancer cells in vitro. This increased migration could be attributed to the ERRα/β-cat–dependent induction of WNT11. Specifically, using (a) conditioned medium from cells overexpressing recombinant WNT11 or (b) WNT11 neutralizing antibodies, we were able to show that this protein was the key mediator of the promigratory activities of ERRα/β-cat. Together, these data provide evidence for an autocrine regulatory loop involving transcriptional upregulation of WNT11 by ERRα and β-cat that influences the migratory capacity of cancer cells. Cancer Res; 70(22); 9298–308. ©2010 AACR.
Data from A Therapeutic OX40 Agonist Dynamically Alters Dendritic, Endothelial, and T Cell Subsets within the Established Tumor Microenvironment
Authors: Pardee Angela D. , McCurry Dustin , Alber Sean , Hu Peisheng , Epstein Alan L. , Storkus Walter J.
Published: March 2024

Abstract
Little preclinical modeling currently exists to support the use of OX40 agonists as therapeutic agents in the setting of advanced cancers, as well as the mechanisms through which therapeutic efficacy is achieved. We show that treatment of mice bearing well-established day 17 sarcomas with a novel OX40 ligand–Fc fusion protein (OX40L-Fc) resulted in tumor regression or dormancy in the majority of treated animals. Unexpectedly, dendritic cells (DC) in the progressive tumor microenvironment (TME) acquire OX40 expression and bind fluorescently labeled OX40L-Fc. Furthermore, longitudinal analyses revealed that DCs become enriched in the tumor-draining lymph node (TDLN) of both wild-type and Rag−/− mice within 3 days after OX40L-Fc treatment. By day 7 after treatment, a significant expansion of CXCR3+ T effector cells was noted in the TDLN, and by day 10 after treatment, type 1 polarized T cells exhibiting a reactivated memory phenotype had accumulated in the tumors. High levels of CXCL9 (a CXCR3 ligand) and enhanced expression of VCAM-1 by vascular endothelial cells (VEC) were observed in the TME early after treatment with OX40L-Fc. Notably, these vascular alterations were maintained in Rag−/− mice, indicating that the OX40L-Fc–mediated activation of both DC and VEC occurs in a T-cell–independent manner. Collectively, these findings support a paradigm in which the stimulation of DC, T cells, and the tumor vasculature by an OX40 agonist dynamically orchestrates the activation, expansion, and recruitment of therapeutic T cells into established tumors. Cancer Res; 70(22); 9041–52. ©2010 AACR.
Data from Maternal Embryonic Leucine Zipper Kinase Is Upregulated and Required in Mammary Tumor-Initiating Cells In vivo
Authors: Hebbard Lionel W. , Maurer Jochen , Miller Amber , Lesperance Jacqueline , Hassell John , Oshima Robert G. , Terskikh Alexey V.
Published: March 2024

Abstract
Maternal embryonic leucine zipper kinase (MELK) is expressed in several developing tissues, in the adult germ line, and in adult neural progenitors. MELK expression is elevated in aggressive undifferentiated tumors, correlating with poor patient outcome in human breast cancer. To investigate the role of MELK in mammary tumorigenesis in vivo, we used a MELK-green fluorescent protein (GFP) reporter mouse, which allows prospective isolation of MELK-expressing cells based on GFP fluorescence. We found that in the normal mammary gland, cells expressing high levels of MELK were enriched in proliferating cells that express markers of mammary progenitors. The isolation of cells with high levels of MELK in mammary tumors from MMTV-Wnt1/MELK-GFP bitransgenic mice resulted in a significant enrichment of tumorsphere formation in culture and tumor initiation after transplantation into mammary fat pads of syngeneic mice. Furthermore, using lentiviral delivery of MELK-specific shRNA and limiting dilution cell transplantations, we showed that MELK function is required for mammary tumorigenesis in vivo. Our findings identify MELK as a potential target in breast tumor-initiating cells. Cancer Res; 70(21); 8863–73. ©2010 AACR.
Data from Natural Killer Cell Cytotoxicity Is Suppressed by Exposure to the Human NKG2D Ligand MICA*008 That Is Shed by Tumor Cells in Exosomes
Authors: Ashiru Omodele , Boutet Philippe , Fernández-Messina Lola , Agüera-González Sonia , Skepper Jeremy N. , Valés-Gómez Mar , Reyburn Hugh T.
Published: March 2024

Abstract
The MHC class I–related chain (MIC) A and MICB ligands for the activating receptor NKG2D can be shed from tumor cells, and the presence of these soluble molecules in sera is related with compromised immune response and progression of disease. Recently, thiol disulphide isomerases and members of the ADAM (a disintegrin and metalloproteinase) gene family were identified as key enzymes in mediating MICA/B shedding from cells. Here, we report shedding of the most frequently expressed MICA allele in human populations (MICA*008) into exosomes, small membrane vesicles that are secreted upon fusion with the plasma membrane. Although similar to other MICA/B molecules in the extracellular domain, the predicted transmembrane and cytoplasmic domains of MICA*008 are quite different, and this difference seemed to be critical for the mode of release from tumor cells. Treatment of natural killer (NK) cells with exosomes containing MICA*008 molecules not only triggered downregulation of NKG2D from the cell surface but also provoked a marked reduction in NK cytotoxicity that is independent of NKG2D ligand expression by the target cell. Our findings reveal a mechanism of NK suppression in cancer that may facilitate immune escape and progression. Cancer Res; 70(2); 481–9
Data from FKBPL Regulates Estrogen Receptor Signaling and Determines Response to Endocrine Therapy
Authors: McKeen Hayley D. , Byrne Christopher , Jithesh Puthen V. , Donley Christopher , Valentine Andrea , Yakkundi Anita , O'Rourke Martin , Swanton Charles , McCarthy Helen O. , Hirst David G. , Robson Tracy
Published: March 2024

Abstract
The HSP90 chaperone and immunophilin FKBPL is an estrogen-responsive gene that interacts with estogen receptor α (ERα) and regulates its levels. In this study, we explored the effects of FKBPL on breast cancer proliferation. Breast cancer cells stably overexpressing FKBPL became dependent on estrogen for their growth and were dramatically more sensitive to the antiestrogens tamoxifen and fulvestrant, whereas FKBPL knockdown reverses this phenotype. FKBPL knockdown also decreased the levels of the cell cycle inhibitor p21WAF1 and increased ERα phosphorylation on Ser118 in response to 17β-estradiol and tamoxifen. In support of the likelihood that these effects explained FKBPL-mediated cell growth inhibition and sensitivity to endocrine therapies, FKBPL expression was correlated with increased overall survival and distant metastasis-free survival in breast cancer patients. Our findings suggest that FKBPL may have prognostic value based on its impact on tumor proliferative capacity and sensitivity to endocrine therapies, which improve outcome. Cancer Res; 70(3); 1090–100
Data from Loss of Function of the Tumor Suppressor DKC1 Perturbs p27 Translation Control and Contributes to Pituitary Tumorigenesis
Authors: Bellodi Cristian , Krasnykh Olya , Haynes Nikesha , Theodoropoulou Marily , Peng Guang , Montanaro Lorenzo , Ruggero Davide
Published: March 2024

Abstract
Mutations in DKC1, encoding for dyskerin, a pseudouridine synthase that modifies rRNA and regulates telomerase activity, are associated with ribosomal dysfunction and increased cancer susceptibility in the human syndrome, X-linked dyskeratosis congenita (X-DC). In a mouse model for X-DC, impairments in DKC1 function affected the translation of specific mRNAs harboring internal ribosomal entry site (IRES) elements, including the tumor suppressor, p27. However, how this translational deregulation contributes to tumor initiation and progression remains poorly understood. Here, we report that impairment in p27 IRES-mediated translation due to decreased levels of DKC1 activity markedly increases spontaneous pituitary tumorigenesis in p27 heterozygous mice. Using a new bioluminescent mouse model, we monitored p27 translation in vivo and show that p27 IRES-mediated translation is reduced in the pituitary of DKC1 hypomorphic mice (DKC1m). Furthermore, we show that DKC1 has a critical role in regulating the assembly of the 48S translational preinitiation complex mediated by the p27 IRES element. An analysis of human tumors identified a novel mutation of DKC1 (DKC1S485G) in a human pituitary adenoma. We show that this specific amino acid substitution significantly alters DKC1 stability/pseudouridylation activity, and this correlates with reductions in p27 protein levels. Furthermore, DKC1S485G mutation does not alter telomerase RNA levels. Altogether, these findings show that genetic alterations in DKC1 could contribute to tumorigenesis associated with somatic cancers and establish a critical role for DKC1 in tumor suppression, at least in part, through translational control of p27. Cancer Res; 70(14); 6026–35. ©2010 AACR.
Data from Deubiquitinase Inhibition by Small-Molecule WP1130 Triggers Aggresome Formation and Tumor Cell Apoptosis
Authors: Kapuria Vaibhav , Peterson Luke F. , Fang Dexing , Bornmann William G. , Talpaz Moshe , Donato Nicholas J.
Published: March 2024

Abstract
Recent evidence suggests that several deubiquitinases (DUB) are overexpressed or activated in tumor cells and many contribute to the transformed phenotype. Agents with DUB inhibitory activity may therefore have therapeutic value. In this study, we describe the mechanism of action of WP1130, a small molecule derived from a compound with Janus-activated kinase 2 (JAK2) kinase inhibitory activity. WP1130 induces rapid accumulation of polyubiquitinated (K48/K63-linked) proteins into juxtanuclear aggresomes, without affecting 20S proteasome activity. WP1130 acts as a partly selective DUB inhibitor, directly inhibiting DUB activity of USP9x, USP5, USP14, and UCH37, which are known to regulate survival protein stability and 26S proteasome function. WP1130-mediated inhibition of tumor-activated DUBs results in downregulation of antiapoptotic and upregulation of proapoptotic proteins, such as MCL-1 and p53. Our results show that chemical modification of a previously described JAK2 inhibitor results in the unexpected discovery of a novel DUB inhibitor with a unique antitumor mechanism. Cancer Res; 70(22); 9265–76. ©2010 AACR.
Data from Estimating CDKN2A Carrier Probability and Personalizing Cancer Risk Assessments in Hereditary Melanoma Using MelaPRO
Authors: Wang Wenyi , Niendorf Kristin B. , Patel Devanshi , Blackford Amanda , Marroni Fabio , Sober Arthur J. , Parmigiani Giovanni , Tsao Hensin
Published: March 2024

Abstract
Personalized cancer risk assessment remains an essential imperative in postgenomic cancer medicine. In hereditary melanoma, germline CDKN2A mutations have been reproducibly identified in melanoma-prone kindreds worldwide. However, genetic risk counseling for hereditary melanoma remains clinically challenging. To address this challenge, we developed and validated MelaPRO, an algorithm that provides germline CDKN2A mutation probabilities and melanoma risk to individuals from melanoma-prone families. MelaPRO builds on comprehensive genetic information, and uses Mendelian modeling to provide fine resolution and high accuracy. In an independent validation of 195 individuals from 167 families, MelaPRO exhibited good discrimination with a concordance index (C) of 0.86 [95% confidence intervals (95% CI), 0.75–0.97] and good calibration, with no significant difference between observed and predicted carriers (26; 95% CI, 20–35, as compared with 22 observed). In cross-validation, MelaPRO outperformed the existing predictive model MELPREDICT (C, 0.82; 95% CI, 0.61–0.93), with a difference of 0.05 (95% CI, 0.007–0.17). MelaPRO is a clinically accessible tool that can effectively provide personalized risk counseling for all members of hereditary melanoma families. Cancer Res; 70(2); 552–9
Data from Transcriptional Autoregulation by BRCA1
Authors: De Siervi Adriana , De Luca Paola , Byun Jung S. , Di Li Jun , Fufa Temesgen , Haggerty Cynthia M. , Vazquez Elba , Moiola Cristian , Longo Dan L. , Gardner Kevin
Published: March 2024

Abstract
The BRCA1 gene product plays numerous roles in regulating genome integrity. Its role in assembling supermolecular complexes in response to DNA damage has been extensively studied; however, much less is understood about its role as a transcriptional coregulator. Loss or mutation is associated with hereditary breast and ovarian cancers, whereas altered expression occurs frequently in sporadic forms of breast cancer, suggesting that the control of BRCA1 transcription might be important to tumorigenesis. Here, we provide evidence of a striking linkage between the roles for BRCA1 as a transcriptional coregulator with control of its expression via an autoregulatory transcriptional loop. BRCA1 assembles with complexes containing E2F-1 and RB to form a repressive multicomponent transcriptional complex that inhibits BRCA1 promoter transcription. This complex is disrupted by genotoxic stress, resulting in the displacement of BRCA1 protein from the BRCA1 promoter and subsequent upregulation of BRCA1 transcription. Cells depleted of BRCA1 respond by upregulating BRCA1 transcripts, whereas cells overexpressing BRCA1 respond by downregulating BRCA1 transcripts. Tandem chromatin immmunoprecipitation studies show that BRCA1 is regulated by a dynamic coregulatory complex containing BRCA1, E2F1, and Rb at the BRCA1 promoter that is disrupted by DNA-damaging agents to increase its transcription. These results define a novel transcriptional mechanism of autoregulated homeostasis of BRCA1 that selectively titrates its levels to maintain genome integrity in response to genotoxic insult. Cancer Res; 70(2); 532–42