bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from RG7204 (PLX4032), a Selective BRAFV600E Inhibitor, Displays Potent Antitumor Activity in Preclinical Melanoma Models
Authors: Yang Hong , Higgins Brian , Kolinsky Kenneth , Packman Kathryn , Go Zenaida , Iyer Raman , Kolis Stanley , Zhao Sylvia , Lee Richard , Grippo Joseph F. , Schostack Kathleen , Simcox Mary Ellen , Heimbrook David , Bollag Gideon , Su Fei
Published: March 2024

Abstract
The BRAFV600E mutation is common in several human cancers, especially melanoma. RG7204 (PLX4032) is a small-molecule inhibitor of BRAFV600E kinase activity that is in phase II and phase III clinical testing. Here, we report a preclinical characterization of the antitumor activity of RG7204 using established in vitro and in vivo models of malignant melanoma. RG7204 potently inhibited proliferation and mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase and ERK phosphorylation in a panel of tumor cell lines, including melanoma cell lines expressing BRAFV600E or other mutant BRAF proteins altered at codon 600. In contrast, RG7204 lacked activity in cell lines that express wild-type BRAF or non-V600 mutations. In several tumor xenograft models of BRAFV600E-expressing melanoma, we found that RG7204 treatment caused partial or complete tumor regressions and improved animal survival, in a dose-dependent manner. There was no toxicity observed in any dose group in any of the in vivo models tested. Our findings offer evidence of the potent antitumor activity of RG7204 against melanomas harboring the mutant BRAFV600E gene. Cancer Res; 70(13); 5518–27. ©2010 AACR.
Data from Synthetic Lethality through Combined Notch–Epidermal Growth Factor Receptor Pathway Inhibition in Basal-Like Breast Cancer
Authors: Dong Yiyu , Li Aimin , Wang Jianbo , Weber Jason D. , Michel Loren S.
Published: March 2024

Abstract
Basal-like breast cancers (BLBC) are highly aggressive, yet selective therapies targeting the specific oncoproteins driving these tumors have not been developed. These cancers frequently express epidermal growth factor receptor (EGFR), with resistance to its inhibition being well documented, albeit poorly understood. Notch pathway activation is also common in this breast cancer subtype and can be suppressed by γ-secretase inhibitors, which effectively block receptor cleavage and activation. Herein, we show that although inhibition of either EGFR or Notch signaling alone is insufficient to suppress basal-like breast tumor cell survival and proliferation, simultaneous inhibition uncovers a synthetic lethal relationship between these two oncogenic pathways. This lethality is due in part to significant decreases in AKT activation caused by combined EGFR and Notch inhibition. Expression of the activated form of Notch1 restores AKT activity and enables cells to overcome cell death after dual-pathway blockade. Combined pathway inhibition is also dramatically more effective at suppressing tumor growth in mice than blocking EGFR or Notch signaling alone. Thus, we show that Notch pathway activation contributes to resistance to EGFR inhibition, and provide a novel treatment strategy for BLBCs. Cancer Res; 70(13); 5465–74. ©2010 AACR.
Data from Steroid Receptor Coactivator-3 Expression in Lung Cancer and Its Role in the Regulation of Cancer Cell Survival and Proliferation
Authors: Cai Di , Shames David S. , Raso Maria Gabriela , Xie Yang , Kim Young H. , Pollack Jonathan R. , Girard Luc , Sullivan James P. , Gao Boning , Peyton Michael , Nanjundan Meera , Byers Lauren , Heymach John , Mills Gordon , Gazdar Adi F. , Wistuba Ignacio , Kodadek Thomas , Minna John D.
Published: March 2024

Abstract
Steroid receptor coactivator-3 (SRC-3) is a histone acetyltransferase and nuclear hormone receptor coactivator, located on 20q12, which is amplified in several epithelial cancers and well studied in breast cancer. However, its possible role in lung cancer pathogenesis is unknown. We found SRC-3 to be overexpressed in 27% of non–small cell lung cancer (NSCLC) patients (n = 311) by immunohistochemistry, which correlated with poor disease-free (P = 0.0015) and overall (P = 0.0008) survival. Twenty-seven percent of NSCLCs exhibited SRC-3 gene amplification, and we found that lung cancer cell lines expressed higher levels of SRC-3 than did immortalized human bronchial epithelial cells (HBEC), which in turn expressed higher levels of SRC-3 than did cultured primary human HBECs. Small interfering RNA–mediated downregulation of SRC-3 in high-expressing, but not in low-expressing, lung cancer cells significantly inhibited tumor cell growth and induced apoptosis. Finally, we found that SRC-3 expression is inversely correlated with gefitinib sensitivity and that SRC-3 knockdown results in epidermal growth factor receptor tyrosine kinase inhibitor–resistant lung cancers becoming more sensitive to gefitinib. Taken together, these data suggest that SRC-3 may be an important oncogene and therapeutic target for lung cancer. Cancer Res; 70(16); 6477–85. ©2010 AACR.
Data from Gene Networks and microRNAs Implicated in Aggressive Prostate Cancer
Authors: Wang Liang , Tang Hui , Thayanithy Venugopal , Subramanian Subbaya , Oberg Ann L. , Cunningham Julie M. , Cerhan James R. , Steer Clifford J. , Thibodeau Stephen N.
Published: March 2024

Abstract
Prostate cancer, a complex disease, can be relatively harmless or extremely aggressive. To identify candidate genes involved in causal pathways of aggressive prostate cancer, we implemented a systems biology approach by combining differential expression analysis and coexpression network analysis to evaluate transcriptional profiles using lymphoblastoid cell lines from 62 prostate cancer patients with aggressive phenotype (Gleason grade ≥ 8) and 63 prostate cancer patients with nonaggressive phenotype (Gleason grade ≤ 5). From 13,935 mRNA genes and 273 microRNAs (miRNA) tested, we identified significant differences in 1,100 mRNAs and 7 miRNAs with a false discovery rate (FDR) of <0.01. We also identified a coexpression module demonstrating significant association with the aggressive phenotype of prostate cancer (P = 3.67 × 10−11). The module of interest was characterized by overrepresentation of cell cycle–related genes (FDR = 3.50 × 10−50). From this module, we further defined 20 hub genes that were highly connected to other genes. Interestingly, 5 of the 7 differentially expressed miRNAs have been implicated in cell cycle regulation and 2 (miR-145 and miR-331-3p) are predicted to target 3 of the 20 hub genes. Ectopic expression of these two miRNAs reduced expression of target hub genes and subsequently resulted in cell growth inhibition and apoptosis. These results suggest that cell cycle is likely to be a molecular pathway causing aggressive phenotype of prostate cancer. Further characterization of cell cycle–related genes (particularly, the hub genes) and miRNAs that regulate these hub genes could facilitate identification of candidate genes responsible for the aggressive phenotype and lead to a better understanding of prostate cancer etiology and progression. [Cancer Res 2009;69(24):9490–7]
Data from De novo Discovery of a γ-Secretase Inhibitor Response Signature Using a Novel In vivo Breast Tumor Model
Authors: Watters James W. , Cheng Chun , Majumder Pradip K. , Wang Ruojie , Yalavarthi Sireesha , Meeske Carol , Kong Lingxin , Sun Wenping , Lin Jie , Heyer Joerg , Ware Chris , Winter Christopher , Reilly John F. , Demuth Tim , Clark Steve , Chiu M. Isabel , Robinson Murray O. , Kohl Nancy , Kannan Karuppiah
Published: March 2024

Abstract
Notch pathway signaling plays a fundamental role in normal biological processes and is frequently deregulated in many cancers. Although several hypotheses regarding cancer subpopulations most likely to respond to therapies targeting the Notch pathway have been proposed, clinical utility of these predictive markers has not been shown. To understand the molecular basis of γ-secretase inhibitor (GSI) sensitivity in breast cancer, we undertook an unbiased, de novo responder identification study using a novel genetically engineered in vivo breast cancer model. We show that tumors arising from this model are heterogeneous on the levels of gene expression, histopathology, growth rate, expression of Notch pathway markers, and response to GSI treatment. In addition, GSI treatment of this model was associated with inhibition of Hes1 and proliferation markers, indicating that GSI treatment inhibits Notch signaling. We then identified a pretreatment gene expression signature comprising 768 genes that is significantly associated with in vivo GSI efficacy across 99 tumor lines. Pathway analysis showed that the GSI responder signature is enriched for Notch pathway components and inflammation/immune-related genes. These data show the power of this novel in vivo model system for the discovery of biomarkers predictive of response to targeted therapies, and provide a basis for the identification of human breast cancers most likely to be sensitive to GSI treatment. [Cancer Res 2009;69(23):8949–57]
Data from KRAB Zinc Finger Protein ZNF382 Is a Proapoptotic Tumor Suppressor That Represses Multiple Oncogenes and Is Commonly Silenced in Multiple Carcinomas
Authors: Cheng Yingduan , Geng Hua , Cheng Suk Hang , Liang Pei , Bai Yan , Li Jisheng , Srivastava Gopesh , Ng Margaret H.L. , Fukagawa Tatsuo , Wu Xiushan , Chan Anthony T.C. , Tao Qian
Published: March 2024

Abstract
Zinc finger transcription factors are involved broadly in development and tumorigenesis. Here, we report that the little studied zinc finger transcription factor ZNF382 functions as a tumor suppressor in multiple carcinomas. Although broadly expressed in normal tissues, ZNF382 expression was attenuated in multiple carcinoma cell lines due to promoter CpG methylation. ZNF382 was also frequently methylated in multiple primary tumors (nasopharyngeal, esophageal, colon, gastric, and breast). Ectopic expression of ZNF382 in silenced tumor cells significantly inhibited their clonogenicity and proliferation and induced apoptosis. We further found that ZNF382 inhibited NF-κB and AP-1 signaling and downregulated the expression of multiple oncogenes including MYC, MITF, HMGA2, and CDK6, as well as the NF-κB upstream factors STAT3, STAT5B, ID1, and IKBKE, most likely through heterochromatin silencing. ZNF382 could suppress tumorigenesis through heterochromatin-mediated silencing, as ZNF382 was colocalized and interacted with heterochromatin protein HP1 and further changed the chromatin modifications of ZNF382 target oncogenes. Our data show that ZNF382 is a functional tumor suppressor frequently methylated in multiple carcinomas. Cancer Res; 70(16); 6516–26. ©2010 AACR.
Data from Definition of microRNAs That Repress Expression of the Tumor Suppressor Gene FOXO1 in Endometrial Cancer
Authors: Myatt Stephen S. , Wang Jun , Monteiro Lara J. , Christian Mark , Ho Ka-Kei , Fusi Luca , Dina Roberto E. , Brosens Jan J. , Ghaem-Maghami Sadaf , Lam Eric W-F.
Published: March 2024

Abstract
Endometrial cancer is the most common malignancy of the lower female reproductive tract. The tumor suppressor FOXO1 is downregulated in endometrial cancer compared with normal endometrium but the underlying mechanisms are not well understood. Using microRNA (miR) target prediction algorithms, we identified several miRs that potentially bind the 3′-untranslated region of FOXO1 transcripts. Expression profiling of normal and malignant endometrial samples by quantitative real-time PCR and Northern blot analysis revealed an inverse correlation between the levels of FOXO1 protein and the abundance of several of the in silico–predicted miRs, suggesting that loss of FOXO1 expression in endometrial cancer may be mediated by miRs. To determine the role of candidate miRs, we used the endometrial cancer cell lines HEC-1B and Ishikawa, which express FOXO1 at high and low levels, respectively. Expression of miR-9, miR-27, miR-96, miR-153, miR-182, miR-183, or miR-186, but not miR-29a, miR-128, miR-152, or miR-486 mimetics in HEC-1B cells was sufficient to significantly reduce the abundance of FOXO1. Conversely, FOXO1 expression was efficiently restored in the Ishikawa cell line upon simultaneous inhibition of miR-9, miR-27, miR-96, miR-153, miR-183, and miR-186. Moreover, induction of FOXO1 in Ishikawa cells by miR inhibitors was accompanied by G1 cell cycle arrest and cell death, and was attenuated by the small interfering RNA–mediated downregulation of FOXO1 expression. Our findings identify several miRs overexpressed in endometrial cancer that function in concert to repress FOXO1 expression. Further, aberrant miR expression results in deregulated cell cycle control and impaired apoptotic responses, and thus, may be central to endometrial tumorigenesis. Cancer Res; 70(1); 367–77
Data from Genome-Wide Mapping of Estrogen Receptor-β–Binding Regions Reveals Extensive Cross-Talk with Transcription Factor Activator Protein-1
Authors: Zhao Chunyan , Gao Hui , Liu Yawen , Papoutsi Zoi , Jaffrey Sadaf , Gustafsson Jan-Åke , Dahlman-Wright Karin
Published: March 2024

Abstract
Estrogen signaling can occur through a nonclassical pathway involving the interaction of estrogen receptors (ER) with other transcription factors such as activator protein-1 (AP-1) and SP-1. However, there is little mechanistic understanding about this pathway, with conflicting results from in vitro investigations. In this study, we applied the ChIP-on-chip approach to identify ERβ-binding sites on a genome-wide scale, identifying 1,457 high-confidence binding sites in ERβ-overexpressing MCF7 breast cancer cells. Genes containing ERβ-binding sites can be regulated by E2. Notably, ∼60% of the genomic regions bound by ERβ contained AP-1–like binding regions and estrogen response element–like sites, suggesting a functional association between AP-1 and ERβ signaling. Chromatin immunoprecipitation (ChIP) analysis confirmed the association of AP-1, which is composed of the oncogenic transcription factors c-Fos and c-Jun, to ERβ-bound DNA regions. Using a re-ChIP assay, we showed co-occupancy of ERβ and AP-1 on chromatin. Short interfering RNA–mediated knockdown of c-Fos or c-Jun expression decreased ERβ recruitment to chromatin, consistent with the role of AP-1 in mediating estrogen signaling in breast cancer cells. Additionally, ERα and ERβ recruitment to AP-1/ERβ target regions exhibited gene-dependent differences in response to antiestrogens. Together, our results broaden insights into ERβ DNA-binding at the genomic level by revealing crosstalk with the AP-1 transcription factor. Cancer Res; 70(12); 5174–83. ©2010 AACR.
Data from Gr-1+CD11b+ Myeloid Cells Tip the Balance of Immune Protection to Tumor Promotion in the Premetastatic Lung
Authors: Yan Hannah H. , Pickup Michael , Pang Yanli , Gorska Agnieszka E. , Li Zhaoyang , Chytil Anna , Geng Yipeng , Gray Jerome W. , Moses Harold L. , Yang Li
Published: March 2024

Abstract
The mechanisms by which a primary tumor affects a selected distant organ before tumor cell arrival remain to be elucidated. This report shows that Gr-1+CD11b+ cells are significantly increased in lungs of mice bearing mammary adenocarcinomas before tumor cell arrival. In the premetastatic lungs, these immature myeloid cells significantly decrease IFN-γ production and increase proinflammatory cytokines. In addition, they produce large quantities of matrix metalloproteinase 9 (MMP9) and promote vascular remodeling. Deletion of MMP9 normalizes aberrant vasculature in the premetastatic lung and diminishes lung metastasis. The production and activity of MMP9 is selectively restricted to lungs and organs with a large number of Gr-1+CD11b+ cells. Our work reveals a novel protumor mechanism for Gr-1+CD11b+ cells that changes the premetastatic lung into an inflammatory and proliferative environment, diminishes immune protection, and promotes metastasis through aberrant vasculature formation. Thus, inhibition of Gr-1+CD11b+ cells could normalize the premetastatic lung environment, improve host immunosurveillance, and inhibit tumor metastasis. Cancer Res; 70(15); 6139–49. ©2010 AACR.
Data from GlcNAcylation Plays an Essential Role in Breast Cancer Metastasis
Authors: Gu Yuchao , Mi Wenyi , Ge Yuqing , Liu Haiyan , Fan Qiong , Han Cuifang , Yang Jing , Han Feng , Lu Xinzhi , Yu Wengong
Published: March 2024

Abstract
GlcNAcylation, a dynamic posttranslational modification, is involved in a wide range of biological processes and some human diseases. Although there is emerging evidence that some tumor-associated proteins are modified by GlcNAcylation, the role of GlcNAcylation in tumor progression remains unclear. Here, we show that GlcNAcylation enhances the migration/invasion of breast cancer cells in vitro and lung metastasis in vivo. The decrease of cell surface E-cadherin is the molecular mechanism underlying GlcNAcylation-induced breast cancer metastasis. p120 and β-catenin, but not E-cadherin, are GlcNAcylated; the GlcNAcylation of p120 and β-catenin might play roles in the decrease of cell surface E-cadherin. Moreover, immunohistochemistry analysis indicated that the global GlcNAcylation level in breast tumor tissues is elevated significantly as compared with that in the corresponding adjacent tissues; further, GlcNAcylation was significantly enhanced in metastatic lymph nodes compared with their corresponding primary tumor tissues. This is the first report to clearly elucidate the roles and mechanisms whereby GlcNAcylation influences the malignant properties of breast cancer cells. These results also suggest that GlcNAcylation might be a potential target for the diagnosis and therapy of breast cancer. Cancer Res; 70(15); 6344–51. ©2010 AACR.
Data from Construction and Characterization of a Bispecific Anti-CD20 Antibody with Potent Antitumor Activity against B-Cell Lymphoma
Authors: Li Bohua , Zhang Xunming , Shi Shu , Zhao Lei , Zhang Dapeng , Qian Weizhu , Zheng Lei , Gao Jie , Wang Hao , Guo Yajun
Published: March 2024

Abstract
To develop more effective anti-CD20 reagents for B-cell lymphoma, we designed and constructed a bispecific tetravalent anti-CD20 antibody, 11B8/2F2(ScFvHL)4-Fc, derived from two fully human monoclonal antibodies (mAb), 2F2 and 11B8. 2F2 is a type I CD20 mAb, which is potent in complement-dependent cytotoxicity (CDC) assays but poor at inducing apoptosis, whereas 11B8 is a type II CD20 mAb, which is effective in induction of apoptosis but ineffective in CDC. Our results showed that 11B8/2F2(ScFvHL)4-Fc possessed apoptosis-inducing activity markedly superior to that of 2F2, and even 11B8, 11B8 plus 2F2, and 2F2(ScFvHL)4-Fc, a 2F2-derived monospecific tetravalent antibody developed previously. Interestingly, 11B8/2F2(ScFvHL)4-Fc displayed a similar ability to mediate CDC as 2F2(ScFvHL)4-Fc, although two of its four antigen-binding arms originated from 11B8. To explore why 11B8/2F2(ScFvHL)4-Fc was so potent in both CDC and apoptotic activity, a bispecific divalent antibody composed of 2F2 and 11B8, denoted as 11B8/2F2-ScFvFc, was constructed and characterized. Our results partially explained the reason for the potent CDC and apoptosis-inducing activity of 11B8/2F2(ScFvHL)4-Fc. Further in vivo therapy studies showed that 11B8/2F2(ScFvHL)4-Fc had a significantly more potent antitumor activity compared with 2F2, 11B8, 2F2 plus 11B8, and 2F2(ScFvHL)4-Fc. These data suggest that 11B8/2F2(ScFvHL)4-Fc may serve as a potential therapeutic agent for B-cell lymphoma. Cancer Res; 70(15); 6293–302. ©2010 AACR.
Data from In silico Estimates of Tissue Components in Surgical Samples Based on Expression Profiling Data
Authors: Wang Yipeng , Xia Xiao-Qin , Jia Zhenyu , Sawyers Anne , Yao Huazhen , Wang-Rodriquez Jessica , Mercola Dan , McClelland Michael
Published: March 2024

Abstract
Tissue samples from many diseases have been used for gene expression profiling studies, but these samples often vary widely in the cell types they contain. Such variation could confound efforts to correlate expression with clinical parameters. In principle, the proportion of each major tissue component can be estimated from the profiling data and used to triage samples before studying correlations with disease parameters. Four large gene expression microarray data sets from prostate cancer, whose tissue components were estimated by pathologists, were used to test the performance of multivariate linear regression models for in silico prediction of major tissue components. Ten-fold cross-validation within each data set yielded average differences between the pathologists' predictions and the in silico predictions of 8% to 14% for the tumor component and 13% to 17% for the stroma component. Across independent data sets that used similar platforms and fresh frozen samples, the average differences were 11% to 12% for tumor and 12% to 17% for stroma. When the models were applied to 219 arrays of “tumor-enriched” samples in the literature, almost one quarter were predicted to have 30% or less tumor cells. Furthermore, there was a 10.5% difference in the average predicted tumor content between 37 recurrent and 42 nonrecurrent cancer patients. As a result, genes that correlated with tissue percentage generally also correlated with recurrence. If such a correlation is not desired, then some samples might be removed to rebalance the data set or tissue percentages might be incorporated into the prediction algorithm. A web service, “CellPred,” has been designed for the in silico prediction of sample tissue components based on expression data. Cancer Res; 70(16); 6448–55. ©2010 AACR.
Data from Preclinical Profile of a Potent γ-Secretase Inhibitor Targeting Notch Signaling with In vivo Efficacy and Pharmacodynamic Properties
Authors: Luistro Leopoldo , He Wei , Smith Melissa , Packman Kathryn , Vilenchik Maria , Carvajal Daisy , Roberts John , Cai James , Berkofsky-Fessler Windy , Hilton Holly , Linn Michael , Flohr Alexander , Jakob-Røtne Roland , Jacobsen Helmut , Glenn Kelli , Heimbrook David , Boylan John F.
Published: March 2024

Abstract
Notch signaling is an area of great interest in oncology. RO4929097 is a potent and selective inhibitor of γ-secretase, producing inhibitory activity of Notch signaling in tumor cells. The RO4929097 IC50 in cell-free and cellular assays is in the low nanomolar range with >100-fold selectivity with respect to 75 other proteins of various types (receptors, ion channels, and enzymes). RO4929097 inhibits Notch processing in tumor cells as measured by the reduction of intracellular Notch expression by Western blot. This leads to reduced expression of the Notch transcriptional target gene Hes1. RO4929097 does not block tumor cell proliferation or induce apoptosis but instead produces a less transformed, flattened, slower-growing phenotype. RO4929097 is active following oral dosing. Antitumor activity was shown in 7 of 8 xenografts tested on an intermittent or daily schedule in the absence of body weight loss or Notch-related toxicities. Importantly, efficacy is maintained after dosing is terminated. Angiogenesis reverse transcription-PCR array data show reduced expression of several key angiogenic genes. In addition, comparative microarray analysis suggests tumor cell differentiation as an additional mode of action. These preclinical results support evaluation of RO4929097 in clinical studies using an intermittent dosing schedule. A multicenter phase I dose escalation study in oncology is under way. [Cancer Res 2009;69(19):7672–80]
Data from Effects of Ionizing Radiation on Self-Renewal and Pluripotency of Human Embryonic Stem Cells
Authors: Wilson Kitchener D. , Sun Ning , Huang Mei , Zhang Wendy Y. , Lee Andrew S. , Li Zongjin , Wang Shan X. , Wu Joseph C.
Published: March 2024

Abstract
Human embryonic stem cells (hESC) present a novel platform for in vitro investigation of the early embryonic cellular response to ionizing radiation. Thus far, no study has analyzed the genome-wide transcriptional response to ionizing radiation in hESCs, nor has any study assessed their ability to form teratomas, the definitive test of pluripotency. In this study, we use microarrays to analyze the global gene expression changes in hESCs after low-dose (0.4 Gy), medium-dose (2 Gy), and high-dose (4 Gy) irradiation. We identify genes and pathways at each radiation dose that are involved in cell death, p53 signaling, cell cycling, cancer, embryonic and organ development, and others. Using Gene Set Enrichment Analysis, we also show that the expression of a comprehensive set of core embryonic transcription factors is not altered by radiation at any dose. Transplantation of irradiated hESCs to immune-deficient mice results in teratoma formation from hESCs irradiated at all doses, definitive proof of pluripotency. Further, using a bioluminescence imaging technique, we have found that irradiation causes hESCs to initially die after transplantation, but the surviving cells quickly recover by 2 weeks to levels similar to control. To conclude, we show that similar to somatic cells, irradiated hESCs suffer significant death and apoptosis after irradiation. However, they continue to remain pluripotent and are able to form all three embryonic germ layers. Studies such as this will help define the limits for radiation exposure for pregnant women and also radiotracer reporter probes for tracking cellular regenerative therapies. Cancer Res; 70(13); 5539–48. ©2010 AACR.
Data from Genome-Wide siRNA Screen for Modulators of Cell Death Induced by Proteasome Inhibitor Bortezomib
Authors: Chen Siquan , Blank Jonathan L. , Peters Theodore , Liu Xiaozhen J. , Rappoli David M. , Pickard Michael D. , Menon Saurabh , Yu Jie , Driscoll Denise L. , Lingaraj Trupti , Burkhardt Anne L. , Chen Wei , Garcia Khristofer , Sappal Darshan S. , Gray Jesse , Hales Paul , Leroy Patrick J. , Ringeling John , Rabino Claudia , Spelman James J. , Morgenstern Jay P. , Lightcap Eric S.
Published: March 2024

Abstract
Multiple pathways have been proposed to explain how proteasome inhibition induces cell death, but mechanisms remain unclear. To approach this issue, we performed a genome-wide siRNA screen to evaluate the genetic determinants that confer sensitivity to bortezomib (Velcade (R); PS-341). This screen identified 100 genes whose knockdown affected lethality to bortezomib and to a structurally diverse set of other proteasome inhibitors. A comparison of three cell lines revealed that 39 of 100 genes were commonly linked to cell death. We causally linked bortezomib-induced cell death to the accumulation of ASF1B, Myc, ODC1, Noxa, BNIP3, Gadd45α, p-SMC1A, SREBF1, and p53. Our results suggest that proteasome inhibition promotes cell death primarily by dysregulating Myc and polyamines, interfering with protein translation, and disrupting essential DNA damage repair pathways, leading to programmed cell death. Cancer Res; 70(11); 4318–26. ©2010 AACR.
Data from Differential Destruction of Stem Cells: Implications for Targeted Cancer Stem Cell Therapy
Authors: Sehl Mary E. , Sinsheimer Janet S. , Zhou Hua , Lange Kenneth L.
Published: March 2024

Abstract
Cancer stem cells represent a novel therapeutic target. The major challenge in targeting leukemic stem cells (LSC) is finding therapies that largely spare normal hematopoietic stem cells (HSC) while eradicating quiescent LSCs. We present a mathematical model to predict how selective a therapy must be to ensure that enough HSCs survive when LSCs have been eradicated. Stem cell population size is modeled as a birth-death process. This permits comparison of LSC and HSC eradication times under therapy and calculation of the number of HSCs at the time of LSC eradication for varied initial population sizes and stem cell death rates. We further investigate the effects of LSC quiescence and resistance mutations on our predictions. From a clinical point of view, our models suggest criteria by which cancer stem cell therapy safety can be assessed. We anticipate that in conjunction with experimental observation of cancer stem cell killing rates, our results will be useful in screening targeted therapies for both hematologic and solid tumor malignancies. [Cancer Res 2009;69(24):9481–9]
Data from Matrix Metalloproteinase-14 (MT1-MMP)–Mediated Endoglin Shedding Inhibits Tumor Angiogenesis
Authors: Hawinkels Lukas J.A.C. , Kuiper Patricia , Wiercinska Eliza , Verspaget Hein W. , Liu Zhen , Pardali Evangelia , Sier Cornelis F.M. , ten Dijke Peter
Published: March 2024

Abstract
Endoglin is a transforming growth factor-β coreceptor with a crucial role in angiogenesis. A soluble form of endoglin is present in the circulation, but the role of soluble endoglin (sEndoglin) is poorly understood. In addition, the endoglin shedding mechanism is not known. Therefore, we examined the role of sEndoglin in tumor angiogenesis and the mechanism by which the extracellular domain of endoglin is released from the membrane.In colorectal cancer specimens, we observed high endothelial endoglin protein expression, accompanied with slightly lower sEndoglin levels in the circulation, compared with healthy controls. In vitro analysis using endothelial sprouting assays revealed that sEndoglin reduced spontaneous and vascular endothelial growth factor–induced endothelial sprouting. Human umbilical vascular endothelial cells were found to secrete high levels of sEndoglin. Endoglin shedding was inhibited by matrix metalloproteinase (MMP) inhibitors and MMP-14 short hairpin RNA, indicating MMP-14 as the major endoglin shedding protease. Coexpression of endoglin and membrane-bound MMP-14 led to a strong increase in sEndoglin levels. Endoglin shedding required a direct interaction between endoglin and membrane-localized MMP-14. Using cleavage site mutants, we determined that MMP-14 cleaved endoglin at a site in close proximity to the transmembrane domain. Taken together, this study shows that MMP-14 mediates endoglin shedding, which may regulate the angiogenic potential of endothelial cells in the (colorectal) tumor microenvironment. Cancer Res; 70(10); 4141–50. ©2010 AACR.
Data from Inhibition of the Androgen Receptor as a Novel Mechanism of Taxol Chemotherapy in Prostate Cancer
Authors: Gan Lu , Chen Shuai , Wang Yuwei , Watahiki Akira , Bohrer Laura , Sun Zhen , Wang Yuzhuo , Huang Haojie
Published: March 2024

Abstract
Taxol chemotherapy is one of the few therapeutic options for men with castration-resistant prostate cancer (CRPC). However, the working mechanisms for Taxol are not fully understood. Here, we showed that treatment of 22Rv1, a PTEN-positive CRPC cell line, with paclitaxel and its semisynthetic analogue docetaxel decreases expression of the androgen receptor (AR)–activated genes prostate-specific antigen (PSA) and Nkx3.1 but increases expression of the AR repression gene maspin, suggesting that Taxol treatment inhibits AR activity. This was further supported by the observation that the activity of AR luciferase reporter genes was inhibited by paclitaxel. In contrast, paclitaxel treatment failed to inhibit AR activity in the PTEN-null CRPC cell line C4-2. However, pretreatment of C4-2 cells with the phosphoinositide 3-kinase inhibitor LY294002 restored paclitaxel inhibition of the AR. Treatment of 22Rv1 xenografts in mice with docetaxel induced mitotic arrest and a decrease in PSA expression in tumor cells adjacent to vascular vessels. We further showed that paclitaxel induces nuclear accumulation of FOXO1, a known AR suppressive nuclear factor, and increases the association of FOXO1 with AR proteins in the nucleus. FOXO1 knockdown with small interfering RNA attenuated the inhibitory effect of paclitaxel on AR transcriptional activity, expression of PSA and Nkx3.1, and cell survival. These data reveal a previously uncharacterized, FOXO1-mediated, AR-inhibitory effect of Taxol in CRPC cells that may play an important role in Taxol-mediated inhibition of CRPC growth. [Cancer Res 2009;69(21):8386–94]
Data from Insulin-Like Growth Factor-I Regulates the Liver Microenvironment in Obese Mice and Promotes Liver Metastasis
Authors: Wu Yingjie , Brodt Pnina , Sun Hui , Mejia Wilson , Novosyadlyy Ruslan , Nunez Nomeli , Chen Xiaoli , Mendoza Arnulfo , Hong Sung-Hyeok , Khanna Chand , Yakar Shoshana
Published: March 2024

Abstract
Among the mechanisms implicated in the tumor-promoting effects of obesity, signaling by insulin-like growth factor-I (IGF-I) and insulin has received considerable attention. However, the emerging realization that obesity is associated with chronic inflammation has prompted other consideration of how the IGF-I axis may participate in cancer progression. In the present study, we used two mouse models of chronic (LID) and inducible (iLID) igf-1 gene deficiency in the liver to investigate the role of IGF-I in regulating the host microenvironment and colorectal carcinoma growth and metastasis in obese mice. Obese mice had a heightened inflammatory response in the liver, which was abolished in mice with chronic IGF-I deficiency (LID). In control animals changes to the hepatic microenvironment associated with obesity sustained the presence of tumor cells in the liver and increased the incidence of hepatic metastases after intrasplenic/portal inoculation of colon carcinoma cells. These changes did not occur in LID mice with chlonic IGF-1 deficiency. In contrast, these changes occured in iLID mice with acute IGF-1 deficiency, in the same manner as the control animals, revealing a fundamental difference in the nature of the requirement for IGF-1 on tumor growth and metastasis. In the setting of obesity, our findings imply that IGF-1 is critical to activate and sustain an inflammatory response in the liver that is needed for hepatic metastasis, not only through direct, paracrine effect on tumor cell growth, but also through indirect effects involving the tumor microenvironment. Cancer Res; 70(1); 57–67
Data from Compensatory Upregulation of Tyrosine Kinase Etk/BMX in Response to Androgen Deprivation Promotes Castration-Resistant Growth of Prostate Cancer Cells
Authors: Dai Bojie , Chen Hege , Guo Shengjie , Yang Xi , Linn Douglas E. , Sun Feng , Li Wei , Guo Zhiyong , Xu Kexin , Kim Oekyung , Kong Xiangtian , Melamed Jonathan , Qiu Shaopeng , Chen Hegang , Qiu Yun
Published: March 2024

Abstract
We previously showed that targeted expression of non–receptor tyrosine kinase Etk/BMX in mouse prostate induces prostate intraepithelial neoplasia, implying a possible causal role of Etk in prostate cancer development and progression. Here, we report that Etk is upregulated in both human and mouse prostates in response to androgen ablation. Etk expression seems to be differentially regulated by androgen and interleukin 6 (IL-6), which is possibly mediated by the androgen receptor (AR) in prostate cancer cells. Our immunohistochemical analysis of tissue microarrays containing 112 human prostate tumor samples revealed that Etk expression is elevated in hormone-resistant prostate cancer and positively correlated with tyrosine phosphorylation of AR (Pearson correlation coefficient ρ = 0.71, P < 0.0001). AR tyrosine phosphorylation is increased in Etk-overexpressing cells, suggesting that Etk may be another tyrosine kinase, in addition to Src and Ack-1, which can phosphorylate AR. We also showed that Etk can directly interact with AR through its Src homology 2 domain, and such interaction may prevent the association of AR with Mdm2, leading to stabilization of AR under androgen-depleted conditions. Overexpression of Etk in androgen-sensitive LNCaP cells promotes tumor growth while knocking down Etk expression in hormone-insensitive prostate cancer cells by a specific shRNA that inhibits tumor growth under androgen-depleted conditions. Taken together, our data suggest that Etk may be a component of the adaptive compensatory mechanism activated by androgen ablation in prostate and may play a role in hormone resistance, at least in part, through direct modulation of the AR signaling pathway. Cancer Res; 70(13); 5587–96. ©2010 AACR.
Data from Elevation of Receptor Tyrosine Kinase EphA2 Mediates Resistance to Trastuzumab Therapy
Authors: Zhuang Guanglei , Brantley-Sieders Dana M. , Vaught David , Yu Jian , Xie Lu , Wells Sam , Jackson Dowdy , Muraoka-Cook Rebecca , Arteaga Carlos , Chen Jin
Published: March 2024

Abstract
One arising challenge in the treatment of breast cancer is the development of therapeutic resistance to trastuzumab, an antibody targeting the human epidermal growth factor receptor-2 (HER2), which is frequently amplified in breast cancers. In this study, we provide evidence that elevated level of the receptor tyrosine kinase Eph receptor A2 (EphA2) is an important contributor to trastuzumab resistance. In a screen of a large cohort of human breast cancers, we found that EphA2 overexpression correlated with a decrease in disease-free and overall survival of HER2-overexpressing patients. Trastuzumab-resistant cell lines overexpressed EphA2, whereas inhibiting EphA2 restored sensitivity to trastuzumab treatment in vivo. Notably, trastuzumab treatment could promote EphA2 phosphorylation by activating Src kinase, leading in turn to an amplification of phosphoinositide 3-kinase/Akt and mitogen-activated protein kinase signaling in resistant cells. Our findings offer mechanistic insights into the basis for trastuzumab resistance and rationalize strategies to target EphA2 as a tactic to reverse trastuzumab resistance. Cancer Res; 70(1); 299–308.
Data from Antigen Presentation by Dendritic Cells in Tumors Is Disrupted by Altered Metabolism that Involves Pyruvate Kinase M2 and Its Interaction with SOCS3
Authors: Zhang Zhuohan , Liu Qiaofei , Che Yongzhe , Yuan Xin , Dai Lingyun , Zeng Bin , Jiao Guohui , Zhang Yin , Wu Xue , Yu Yinyan , Zhang Yuan , Yang Rongcun
Published: March 2024

Abstract
Dendritic cell (DC) function is negatively affected by tumors and tumor-derived factors, but little is known about the underlying mechanisms. Here, we show that intracellular SOCS3 in DCs binds to pyruvate kinase type M2 (M2-PK), which plays a critical role in ATP production through glycolysis. The interaction of SOCS3 with M2-PK reduced ATP production and impaired DC-based immunotherapy against tumors. Thus, SOCS3, which has been shown to be upregulated by tumor-derived factors, interacts with M2-PK to decrease ATP production, causing DC dysfunction. These dysfunctional DCs have a reduced ability to present antigens. Alteration of DC metabolism mediated by SOCS3 represents a novel mechanism for DC dysfunction in the tumor microenvironment. Cancer Res; 70(1); 89–98
Data from FOXC1 Is a Potential Prognostic Biomarker with Functional Significance in Basal-like Breast Cancer
Authors: Ray Partha S. , Wang Jinhua , Qu Ying , Sim Myung-Shin , Shamonki Jaime , Bagaria Sanjay P. , Ye Xing , Liu Bingya , Elashoff David , Hoon Dave S. , Walter Michael A. , Martens John W. , Richardson Andrea L. , Giuliano Armando E. , Cui Xiaojiang
Published: March 2024

Abstract
Gene expression signatures for a basal-like breast cancer (BLBC) subtype have been associated with poor clinical outcomes, but a molecular basis for this disease remains unclear. Here, we report overexpression of the transcription factor FOXC1 as a consistent feature of BLBC compared with other molecular subtypes of breast cancer. Elevated FOXC1 expression predicted poor overall survival in BLBC (P = 0.0001), independently of other clinicopathologic prognostic factors including lymph node status, along with a higher incidence of brain metastasis (P = 0.02) and a shorter brain metastasis–free survival in lymph node–negative patients (P < 0.0001). Ectopic overexpression of FOXC1 in breast cancer cells increased cell proliferation, migration, and invasion, whereas shRNA-mediated FOXC1 knockdown yielded opposite effects. Our findings identify FOXC1 as a theranostic biomarker that is specific for BLBC, offering not only a potential prognostic candidate but also a potential molecular therapeutic target in this breast cancer subtype. Cancer Res; 70(10); 3870–6. ©2010 AACR.
Data from A Microfluidic Platform for Systems Pathology: Multiparameter Single-Cell Signaling Measurements of Clinical Brain Tumor Specimens
Authors: Sun Jing , Masterman-Smith Michael D. , Graham Nicholas A. , Jiao Jing , Mottahedeh Jack , Laks Dan R. , Ohashi Minori , DeJesus Jason , Kamei Ken-ichiro , Lee Ki-Bum , Wang Hao , Yu Zeta T.F. , Lu Yi-Tsung , Hou Shuang , Li Keyu , Liu Max , Zhang Nangang , Wang Shutao , Angenieux Brigitte , Panosyan Eduard , Samuels Eric R. , Park Jun , Williams Dirk , Konkankit Vera , Nathanson David , van Dam R. Michael , Phelps Michael E. , Wu Hong , Liau Linda M. , Mischel Paul S. , Lazareff Jorge A. , Kornblum Harley I. , Yong William H. , Graeber Thomas G. , Tseng Hsian-Rong
Published: March 2024

Abstract
The clinical practice of oncology is being transformed by molecular diagnostics that will enable predictive and personalized medicine. Current technologies for quantitation of the cancer proteome are either qualitative (e.g., immunohistochemistry) or require large sample sizes (e.g., flow cytometry). Here, we report a microfluidic platform—microfluidic image cytometry (MIC)—capable of quantitative, single-cell proteomic analysis of multiple signaling molecules using only 1,000 to 2,800 cells. Using cultured cell lines, we show simultaneous measurement of four critical signaling proteins (EGFR, PTEN, phospho-Akt, and phospho-S6) within the oncogenic phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway. To show the clinical application of the MIC platform to solid tumors, we analyzed a panel of 19 human brain tumor biopsies, including glioblastomas. Our MIC measurements were validated by clinical immunohistochemistry and confirmed the striking intertumoral and intratumoral heterogeneity characteristic of glioblastoma. To interpret the multiparameter, single-cell MIC measurements, we adapted bioinformatic methods including self-organizing maps that stratify patients into clusters that predict tumor progression and patient survival. Together with bioinformatic analysis, the MIC platform represents a robust, enabling in vitro molecular diagnostic technology for systems pathology analysis and personalized medicine. Cancer Res; 70(15); 6128–38. ©2010 AACR.
Data from Activation of FOXO3a Is Sufficient to Reverse Mitogen-Activated Protein/Extracellular Signal-Regulated Kinase Kinase Inhibitor Chemoresistance in Human Cancer
Authors: Yang Jer-Yen , Chang Chun-Ju , Xia Weiya , Wang Yan , Wong Kwok-Kin , Engelman Jeffrey A. , Du Yi , Andreeff Michael , Hortobagyi Gabriel N. , Hung Mien-Chie
Published: March 2024

Abstract
Drug resistance is a central challenge of cancer therapy that ultimately leads to treatment failure. In this study, we characterized a mechanism of drug resistance that arises to AZD6244, an established mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK) 1/2 inhibitor currently being evaluated in cancer clinical trials. AZD6244 enhanced the expression of transcription factor FOXO3a, which suppressed cancer cell proliferation. In AZD6244-resistant cancer cells, we observed the impaired nuclear localization of FOXO3a, reduced FOXO3a-mediated transcriptional activity, and decreased the expression of FOXO3a target gene Bim after cell treatment with AZD6244. Resistant cells could be sensitized by phosphoinositide 3-kinase (PI3K)/AKT inhibitors, which are known to enhance FOXO3a nuclear translocation. Our findings define FOXO3a as candidate marker to predict the clinical efficacy of AZD6244. Furthermore, they suggest a mechanism of resistance to MEK inhibitors that may arise in the clinic yet can be overcome by cotreatment with PI3K/AKT inhibitors. Cancer Res; 70(11); 4709–18. ©2010 AACR.
Data from Evaluation of the Proteasome Inhibitor MLN9708 in Preclinical Models of Human Cancer
Authors: Kupperman Erik , Lee Edmund C. , Cao Yueying , Bannerman Bret , Fitzgerald Michael , Berger Allison , Yu Jie , Yang Yu , Hales Paul , Bruzzese Frank , Liu Jane , Blank Jonathan , Garcia Khristofer , Tsu Christopher , Dick Larry , Fleming Paul , Yu Li , Manfredi Mark , Rolfe Mark , Bolen Joe
Published: March 2024

Abstract
The proteasome was validated as an oncology target following the clinical success of VELCADE (bortezomib) for injection for the treatment of multiple myeloma and recurring mantle cell lymphoma. Consequently, severalgroups are pursuing the development of additional small-molecule proteasome inhibitors for both hematologic and solid tumor indications. Here, we describe MLN9708, a selective, orally bioavailable, second-generation proteasome inhibitor that is in phase I clinical development. MLN9708 has a shorter proteasome dissociation half-life and improved pharmacokinetics, pharmacodynamics, and antitumor activity compared with bortezomib. MLN9708 has a larger blood volume distribution at steady state, and analysis of 20S proteasome inhibition and markers of the unfolded protein response confirmed that MLN9708 has greater pharmacodynamic effects in tissues than bortezomib. MLN9708 showed activity in both solid tumor and hematologic preclinical xenograft models, and we found a correlation between greater pharmacodynamic responses and improved antitumor activity. Moreover, antitumor activity was shown via multiple dosing routes, including oral gavage. Taken together, these data support the clinical development of MLN9708 for both hematologic and solid tumor indications. Cancer Res; 70(5); 1970–80
Data from Vitamin D Deficiency Promotes Human Breast Cancer Growth in a Murine Model of Bone Metastasis
Authors: Ooi Li Laine , Zhou Hong , Kalak Robert , Zheng Yu , Conigrave Arthur D. , Seibel Markus J. , Dunstan Colin R.
Published: March 2024

Abstract
Vitamin D exerts antiproliferative, prodifferentiation, and proapoptotic effects on nonclassic target tissues such as breast. Blood levels of 25-hydroxyvitamin D [25(OH)D], the most sensitive indicator of vitamin D status, are inversely correlated with breast cancer risk; however, a causal relationship between vitamin D deficiency and breast cancer growth in bone has not been assessed. We examined the effect of vitamin D deficiency on the intraskeletal growth of the human breast cancer cell line MDA-MB-231-TxSA in a murine model of malignant bone lesions. Subsets of mice were treated concurrently with osteoprotegerin (OPG) to abrogate bone resorption. Outcomes were assessed by repeated radiographic and end-point micro–computed tomography and histologic analyses. Mice weaned onto a vitamin D–free diet developed vitamin D deficiency within 4 weeks [mean ± SE serum 25(OH)D: 11.5 ± 0.5 nmol/L], which was sustained throughout the study and was associated with secondary hyperparathyroidism and accelerated bone turnover. Osteolytic lesions appeared earlier and were significantly larger in vitamin D–deficient than in vitamin D–sufficient mice after 2 weeks (radiographic osteolysis: +121.5%; histologic tumor area: +314%; P < 0.05). Although OPG treatment reduced the size of radiographic osteolyses and tumor area in both groups, tumors remained larger in OPG-treated vitamin D–deficient compared with OPG-treated vitamin D–sufficient mice (0.53 ± 0.05 mm2 versus 0.19 ± 0.05 mm2; P < 0.05). We conclude that vitamin D deficiency promotes the growth of human breast cancer cells in the bones of nude mice. These effects are partly mediated through secondary changes in the bone microenvironment, along with direct effects of vitamin D on tumor growth. Cancer Res; 70(5); 1835–44