bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Chemoprevention of Familial Adenomatous Polyposis by Natural Dietary Compounds Sulforaphane and Dibenzoylmethane Alone and in Combination in ApcMin/+ Mouse
Authors: Shen Guoxiang , Khor Tin Oo , Hu Rong , Yu Siwang , Nair Sujit , Ho Chi-Tang , Reddy Bandaru S. , Huang Mou-Tuan , Newmark Harold L. , Kong Ah-Ng Tony
Published: March 2023

Abstract
Cancer chemopreventive agent sulforaphane (SFN) and dibenzoylmethane (DBM) showed antitumorigenesis effects in several rodent carcinogenesis models. In this study, we investigated the cancer chemopreventive effects and the underlying molecular mechanisms of dietary administration of SFN and DBM alone or in combination in the ApcMin/+ mice model. Male ApcMin/+ mice (12 per group) at age of 5 weeks were given control AIN-76A diet, diets containing 600 ppm SFN and 1.0% DBM, or a combination of 300 ppm SFN and 0.5% DBM for 10 weeks. Mice were then sacrificed, and tumor numbers and size were examined. Microarray analysis, Western blotting, ELISA, and immunohistochemical staining were done to investigate the underlying molecular mechanisms of cancer chemopreventive effects of SFN and DBM. Dietary administrations of SFN and DBM alone or in combination significantly inhibited the development of intestinal adenomas by 48% (P = 0.002), 50% (P = 0.001), and 57% (P < 0.001), respectively. Dietary administration of 600 ppm SFN and 1.0% DBM also reduced colon tumor numbers by 80% (P = 0.016) and 60% (P = 0.103), respectively, whereas the combination of SFN and DBM treatment blocked the colon tumor development (P = 0.002). Both SFN and DBM treatments resulted in decreased levels of prostaglandin E2 or leukotriene B4 in intestinal polyps or apparently normal mucosa. Treatments also led to the inhibition of cell survival and growth-related signaling pathways (such as Akt and extracellular signal-regulated kinase) or biomarkers (such as cyclooxygenase-2, proliferating cell nuclear antigen, cleaved caspases, cyclin D1, and p21). In conclusion, our results showed that both SFN and DBM alone as well as their combination are potent natural dietary compounds for chemoprevention of gastrointestinal cancers. [Cancer Res 2007;67(20):9937–44]
Data from Common and Distinct Genomic Events in Sporadic Colorectal Cancer and Diverse Cancer Types
Authors: Martin Eric S. , Tonon Giovanni , Sinha Raktim , Xiao Yonghong , Feng Bin , Kimmelman Alec C. , Protopopov Alexei , Ivanova Elena , Brennan Cameron , Montgomery Kate , Kucherlapati Raju , Bailey Gerald , Redston Mark , Chin Lynda , DePinho Ronald A.
Published: March 2023

Abstract
Colorectal cancer (CRC) is a major cause of cancer morbidity and mortality, and elucidation of its underlying genetics has advanced diagnostic screening, early detection, and treatment. Because CRC genomes are characterized by numerous non-random chromosomal structural alterations, we sought to delimit regions of recurrent amplifications and deletions in a collection of 42 primary specimens and 37 tumor cell lines derived from chromosomal instability neoplasia and microsatellite instability neoplasia CRC subtypes and to compare the pattern of genomic aberrations in CRC with those in other cancers. Application of oligomer-based array-comparative genome hybridization and custom analytic tools identified 50 minimal common regions (MCRs) of copy number alterations, 28 amplifications, and 22 deletions. Fifteen were highly recurrent and focal (<12 genes) MCRs, five of them harboring known CRC genes including EGFR and MYC with the remaining 10 containing a total of 65 resident genes with established links to cancer. Furthermore, comparisons of these delimited genomic profiles revealed that 22 of the 50 CRC MCRs are also present in lung cancer, glioblastoma, and/or multiple myeloma. Among 22 shared MCRs, nine do not contain genes previously shown genetically altered in cancer, whereas the remaining 13 harbor 35 known cancer genes, of which only 14 have been linked to CRC pathogenesis. Together, these observations point to the existence of many yet-to-be discovered cancer genes driving CRC development, as well as other human cancers, and show the utility of high-resolution copy number analysis in the identification of genetic events common and specific to the development of various tumor types. [Cancer Res 2007;67(22):10736–43]
Data from Angiopoietin-2 Stimulates Breast Cancer Metastasis through the α5β1 Integrin-Mediated Pathway
Authors: Imanishi Yorihisha , Hu Bo , Jarzynka Michael J. , Guo Ping , Elishaev Esther , Bar-Joseph Ifat , Cheng Shi-Yuan
Published: March 2023

Abstract
Acquisition of a metastatic phenotype by breast cancer cells includes alternations of multigenic programs that permit tumor cells to metastasize to distant organs. Here, we report that angiopoietin-2 (Ang2), a known growth factor, is capable of promoting breast cancer cell invasion leading to metastasis. Analysis of 185 primary human breast cancer specimens that include 97 tumors showing lymph node and/or distant metastasis reveals a significant correlation between the expression of Ang2 and E-cadherin, Snail, metastatic potential, tumor grade, and lymph-vascular invasion during breast cancer progression. Using a xenograft model, we show that overexpression of Ang2 in poorly metastatic MCF-7 breast cancer cells suppresses expression of E-cadherin and induces Snail expression and phosphorylation of Akt and glycogen synthase kinase-3β (GSK-3β) promoting metastasis to the lymph nodes and lung. In cell culture, Ang2 promotes cell migration and invasion in Tie2-deficient breast cancer cells through the α5β1 integrin/integrin-linked kinase (ILK)/Akt, GSK-3β/Snail/E-cadherin signaling pathway. Inhibition of ILK and the α5β1 integrin abrogates Ang2 modulation of Akt, GSK-3β, Snail, and E-cadherin and Ang2-stimulated breast cancer cell migration and invasion. Together, these results underscore the significant contribution of Ang2 in cancer progression, not only by stimulating angiogenesis but also by promoting metastasis, and provide a mechanism by which breast cancer cells acquire an enhanced invasive phenotype contributing to metastasis. [Cancer Res 2007;67(9):4254–63]
Data from A Cell Proliferation and Chromosomal Instability Signature in Anaplastic Thyroid Carcinoma
Authors: Salvatore Giuliana , Nappi Tito Claudio , Salerno Paolo , Jiang Yuan , Garbi Corrado , Ugolini Clara , Miccoli Paolo , Basolo Fulvio , Castellone Maria Domenica , Cirafici Anna Maria , Melillo Rosa Marina , Fusco Alfredo , Bittner Michael L. , Santoro Massimo
Published: March 2023

Abstract
Here, we show that the anaplastic thyroid carcinoma (ATC) features the up-regulation of a set of genes involved in the control of cell cycle progression and chromosome segregation. This phenotype differentiates ATC from normal tissue and from well-differentiated papillary thyroid carcinoma. Transcriptional promoters of the ATC up-regulated genes are characterized by a modular organization featuring binding sites for E2F and NF-Y transcription factors and cell cycle–dependent element (CDE)/cell cycle gene homology region (CHR) cis-regulatory elements. Two protein kinases involved in cell cycle regulation, namely, Polo-like kinase 1 (PLK1) and T cell tyrosine kinase (TTK), are part of the gene set that is up-regulated in ATC. Adoptive overexpression of p53, p21 (CIP1/WAF1), and E2F4 down-regulated transcription from the PLK1 and TTK promoters in ATC cells, suggesting that these genes might be under the negative control of tumor suppressors of the p53 and pRB families. ATC, but not normal thyroid, cells depended on PLK1 for survival. RNAi-mediated PLK1 knockdown caused cell cycle arrest associated with 4N DNA content and massive mitotic cell death. Thus, thyroid cell anaplastic transformation is accompanied by the overexpression of a cell proliferation/genetic instability-related gene cluster that includes PLK1 kinase, which is a potential molecular target for ATC treatment. [Cancer Res 2007;67(21):10148–57]
Data from Bryostatin-5 Blocks Stromal Cell–Derived Factor-1 Induced Chemotaxis via Desensitization and Down-regulation of Cell Surface CXCR4 Receptors
Authors: He Xing , Fang Liyan , Wang Jue , Yi Yanghua , Zhang Shuyu , Xie Xin
Published: March 2023

Abstract
The chemokine receptor CXCR4 and its ligand, stromal cell–derived factor-1 (SDF-1), play important roles in hematopoiesis regulation, lymphocyte activation, and trafficking, as well as in developmental processes, including organogenesis, vascularization, and embryogenesis. The receptor is also involved in HIV infection and tumor growth and metastasis. Antagonists of CXCR4 have been widely evaluated for drugs against HIV and tumors. In an effort to identify novel CXCR4 antagonists, we screened a small library of compounds derived from marine organisms and found bryostatin-5, which potently inhibits chemotaxis induced by SDF-1 in Jurkat cells. Bryostatin-5 is a member of the macrolactones, and its analogue bryostatin-1 is currently being evaluated in clinical trials for its chemotherapeutic potential. The involvement of bryostatins in the SDF-1/CXCR4 signaling process has never been reported. In this study, we found that bryostatin-5 potently inhibits SDF-1–induced chemotaxis but does not affect serum-induced chemotaxis. Further studies indicate that this inhibitory effect is not due to receptor antagonism but rather to bryostatin-5–induced receptor desensitization and down-regulation of cell surface CXCR4. We also show that these effects are mediated by the activation of conventional protein kinase C. [Cancer Res 2008;68(21):8678–86]
Data from Negative Feedback Regulation of IFN-γ Pathway by IFN Regulatory Factor 2 in Esophageal Cancers
Authors: Wang Yan , Liu Dongping , Chen Pingping , Koeffler H. Phillip , Tong Xiangjun , Xie Dong
Published: March 2023

Abstract
IFN-γ is an antitumor cytokine that inhibits cell proliferation and induces apoptosis after engagement with the IFN-γ receptors (IFNGR) expressed on target cells, whereas IFN regulatory factor 2 (IRF-2) is able to block the effects of IFN-γ by repressing transcription of IFN-γ–induced genes. Thus far, few studies have explored the influences of IFN-γ on human esophageal cancer cells. In the present study, therefore, we investigated in detail the functions of IFN-γ in esophageal cancer cells. The results in clinical samples of human esophageal cancers showed that the level of IFN-γ was increased in tumor tissues and positively correlated with tumor progression and IRF-2 expression, whereas the level of IFNGR1 was decreased and negatively correlated with tumor progression and IRF-2 expression. Consistently, in vitro experiments showed that low concentration of IFN-γ induced the expression of IRF-2 with potential promotion of cell growth, and moreover, IRF-2 was able to suppress IFNGR1 transcription in human esophageal cancer cells by binding a specific motif in IFNGR1 promoter, which lowered the sensitivity of esophageal cancer cells to IFN-γ. Taken together, our results disclosed a new IRF-2–mediated inhibitory mechanism for IFN-γ–induced pathway in esophageal cancer cells: IFN-γ induced IRF-2 up-regulation, then up-regulated IRF-2 decreased endogenous IFNGR1 level, and finally, the loss of IFNGR1 turned to enhance the resistance of esophageal cancer cells to IFN-γ. Accordingly, the results implied that IRF-2 might act as a mediator for the functions of IFN-γ and IFNGR1 in human esophageal cancers. [Cancer Res 2008;68(4):1136–43]
Data from Noninvasive Imaging and Quantification of Epidermal Growth Factor Receptor Kinase Activation In vivo
Authors: Li Wenrong , Li Fang , Huang Qian , Frederick Barbara , Bao Shideng , Li Chuan-Yuan
Published: March 2023

Abstract
Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase (RTK) critical in tumor growth and a major target for anticancer drug development. However, thus far, there is no effective system to monitor its activities in vivo. Here, we report a novel approach to monitor EGFR activation based on the bifragment luciferase reconstitution system. The EGFR receptor and its interacting partner proteins (EGFR, growth factor receptor binding protein 2, and Src homology 2 domain-containing) were fused to NH2 terminal and COOH terminal fragments of the firefly luciferase. After establishing tumor xenograft from cells transduced with the reporter genes, we show that the activation of EGFR and its downstream factors could be quantified through optical imaging of reconstituted luciferase. Changes in EGFR activation could be visualized after radiotherapy or EGFR inhibitor treatment. Rapid and sustained radiation-induced EGFR activation and inhibitor-mediated signal suppression were observed in the same xenograft tumors over a period of weeks. Our data therefore suggest a new methodology where activities of RTKs can be imaged and quantified optically in mice. This approach should be generally applicable to study biological regulation of RTK, as well as to develop and evaluate novel RTK-targeted therapeutics. [Cancer Res 2008;68(13):4990–7]
Data from Transporter-Mediated Protection against Thiopurine-Induced Hematopoietic Toxicity
Authors: Krishnamurthy Partha , Schwab Matthias , Takenaka Kazumasa , Nachagari Deepa , Morgan Jessica , Leslie Mark , Du Weinan , Boyd Kelli , Cheok Meyling , Nakauchi Hiromitsu , Marzolini Catia , Kim Richard B. , Poonkuzhali Balasubramanian , Schuetz Erin , Evans William , Relling Mary , Schuetz John D.
Published: March 2023

Abstract
Thiopurines are effective immunosuppressants and anticancer agents, but intracellular accumulation of their active metabolites (6-thioguanine nucleotides, 6-TGN) causes dose-limiting hematopoietic toxicity. Thiopurine S-methyltransferase deficiency is known to exacerbate thiopurine toxicity. However, many patients are highly sensitive to thiopurines for unknown reasons. We show that multidrug-resistance protein 4 (Mrp4) is abundant in myeloid progenitors and tested the role of the Mrp4, an ATP transporter of monophosphorylated nucleosides, in this unexplained thiopurine sensitivity. Mrp4-deficient mice experienced Mrp4 gene dosage-dependent toxicity caused by accumulation of 6-TGNs in their myelopoietic cells. Therefore, Mrp4 protects against thiopurine-induced hematopoietic toxicity by actively exporting thiopurine nucleotides. We then identified a single-nucleotide polymorphism (SNP) in human MRP4 (rs3765534) that dramatically reduces MRP4 function by impairing its cell membrane localization. This SNP is common (>18%) in the Japanese population and indicates that the increased sensitivity of some Japanese patients to thiopurines may reflect the greater frequency of this MRP4 SNP. [Cancer Res 2008;68(13):4983–9]
Data from The SV40 Large T Antigen-p53 Complexes Bind and Activate the Insulin-like Growth Factor-I Promoter Stimulating Cell Growth
Authors: Bocchetta Maurizio , Eliasz Sandra , De Marco Melissa Arakelian , Rudzinski Jennifer , Zhang Lei , Carbone Michele
Published: March 2023

Abstract
Inactivation of cellular p53 is a crucial step in carcinogenesis. Accordingly, p53 is inactivated in most human cancers by different mechanisms. In cells infected with DNA tumor viruses, p53 is bound to the viral tumor antigens (Tag). The current “dogma” views the Tag-p53 complexes as a way of sequestering and inactivating p53. Using primary human cells and SV40-transformed human cells, we show that in addition to inactivating p53 tumor suppressor activities, the Tag-p53 complex has growth stimulatory activities that are required for malignant cell growth. We found that in human cells, Tag-p53 complexes regulate transcription of the insulin-like growth factor I (IGF-I) gene by binding to the IGF-I promoter together with pRb and p300. Depletion of p53 leads to structural rearrangements of this multiprotein complex, resulting in IGF-I promoter transcriptional repression and growth arrest. Our data provide a novel mechanistic and biological interpretation of the p53-Tag complexes and of DNA tumor virus transformation in general. In the model we propose, p53 is not a passive inactive partner of Tag. Instead the p53-Tag complex promotes malignant cell growth through its ability to activate the IGF-I signaling pathway. [Cancer Res 2008;68(4):1022–9]
Data from Transforming Growth Factor β Induces Apoptosis through Repressing the Phosphoinositide 3-Kinase/AKT/Survivin Pathway in Colon Cancer Cells
Authors: Wang Jing , Yang Limin , Yang Junhua , Kuropatwinski Karen , Wang Wang , Liu Xiao-Qiong , Hauser Jennie , Brattain Michael G.
Published: March 2023

Abstract
FET cells, derived from an early-stage colon carcinoma, are nontumorigenic in athymic mice. Stable transfection of a dominant-negative transforming growth factor β (TGFβ) type II receptor (DNRII) into FET cells that express autocrine TGFβ shows loss of TGFβ signaling and increased tumorigenicity in vivo indicating tumor suppressor activity of TGFβ signaling in this model. The ability of tumorigenic cells to withstand growth factor and nutrient deprivation stress (GFDS) is widely regarded as a key attribute for tumor formation and progression. We hypothesized that increased tumorigenicity of FET/DNRII cells was due to loss of participation of autocrine TGFβ in a “fail-safe” mechanism to generate cell death in response to this stress. Here, we document that loss of autocrine TGFβ in FET/DNRII cells resulted in greater endogenous cell survival in response to GFDS due to activation of the phosphoinositide 3-kinase (PI3K)/Akt/survivin pathway. Treatment of FET DNRII cells with a PI3K inhibitor (LY294002) inhibited Akt phosphorylation and reduced survivin expression resulting in increased apoptosis in FET/DNRII cells. We also show that exogenous TGFβ increased apoptosis in FET cells through repression of the PI3K/Akt/survivin pathway during GFDS. These results indicate that the PI3K/Akt/survivin pathway is blocked by TGFβ signaling and that loss of autocrine TGFβ leads to increased cell survival during GFDS through the novel linkage of TGFβ-mediated repression of survivin expression. Inhibition of survivin function by dominant-negative approaches showed that this inhibitor of apoptosis family member is critical to cell survival in the FET/DNRII cells, thus indicating the importance of this target for TGFβ-mediated apoptosis. [Cancer Res 2008;68(9):3152–60]
Data from A Notch1 Ectodomain Construct Inhibits Endothelial Notch Signaling, Tumor Growth, and Angiogenesis
Authors: Funahashi Yasuhiro , Hernandez Sonia L. , Das Indranil , Ahn Audrey , Huang Jianzhong , Vorontchikhina Marina , Sharma Anshula , Kanamaru Emi , Borisenko Valeriya , DeSilva Dinuka M. , Suzuki Akihiko , Wang Xing , Shawber Carrie J. , Kandel Jessica J. , Yamashiro Darrell J. , Kitajewski Jan
Published: March 2023

Abstract
Notch signaling is required for vascular development and tumor angiogenesis. Although inhibition of the Notch ligand Delta-like 4 can restrict tumor growth and disrupt neovasculature, the effect of inhibiting Notch receptor function on angiogenesis has yet to be defined. In this study, we generated a soluble form of the Notch1 receptor (Notch1 decoy) and assessed its effect on angiogenesis in vitro and in vivo. Notch1 decoy expression reduced signaling stimulated by the binding of three distinct Notch ligands to Notch1 and inhibited morphogenesis of endothelial cells overexpressing Notch4. Thus, Notch1 decoy functioned as an antagonist of ligand-dependent Notch signaling. In mice, Notch1 decoy also inhibited vascular endothelial growth factor–induced angiogenesis in skin, establishing a role for Notch receptor function in this process. We tested the effects of Notch1 decoy on tumor angiogenesis using two models: mouse mammary Mm5MT cells overexpressing fibroblast growth factor 4 (Mm5MT-FGF4) and NGP human neuroblastoma cells. Exogenously expressed FGF4 induced Notch ligand expression in Mm5MT cells and xenografts. Notch1 decoy expression did not affect tumorigenicity of Mm5MT-FGF4 cells in vitro but restricted Mm5MT-FGF4 xenograft growth in mice while markedly impairing neoangiogenesis. Similarly, Notch1 decoy expression did not affect NGP cells in vitro but disrupted vessels and decreased tumor viability in vivo. These results strongly suggest that Notch receptor signaling is required for tumor neoangiogenesis and provides a new target for tumor therapy. [Cancer Res 2008;68(12):4727–35]
Data from Breast Cancer Risk Reduction and Membrane-Bound Catechol O-Methyltransferase Genetic Polymorphisms
Authors: Ji Yuan , Olson Janet , Zhang Jianping , Hildebrandt Michelle , Wang Liewei , Ingle James , Fredericksen Zachary , Sellers Thomas , Miller William , Dixon J. Michael , Brauch Hiltrud , Eichelbaum Michel , Justenhoven Christina , Hamann Ute , Ko Yon , Brüning Thomas , Chang-Claude Jenny , Wang-Gohrke Shan , Schaid Daniel , Weinshilboum Richard
Published: March 2023

Abstract
Catechol O-methyltransferase (COMT)-catalyzed methylation of catecholestrogens has been proposed to play a protective role in estrogen-induced genotoxic carcinogenesis. We have taken a comprehensive approach to test the hypothesis that genetic variation in COMT might influence breast cancer risk. Fifteen COMT single nucleotide polymorphisms (SNPs) selected on the basis of in-depth resequencing of the COMT gene were genotyped in 1,482 DNA samples from a Mayo Clinic breast cancer case control study. Two common SNPs in the distal promoter for membrane-bound (MB) COMT, rs2020917 and rs737865, were associated with breast cancer risk reduction in premenopausal women in the Mayo Clinic study, with allele-specific odds ratios (OR) of 0.70 [95% confidence interval (CI), 0.52–0.95] and 0.68 (95% CI, 0.51–0.92), respectively. These two SNPs were then subjected to functional genomic analysis and were genotyped in an additional 3,683 DNA samples from two independent case control studies (GENICA and GESBC). Functional genomic experiments showed that these SNPs could up-regulate transcription and that they altered DNA-protein binding patterns. Furthermore, substrate kinetic and exon array analyses suggested a role for MB-COMT in catecholestrogen inactivation. The GENICA results were similar to the Mayo case control observations, with ORs of 0.85 (95% CI, 0.72–1.00) and 0.85 (95% CI, 0.72–1.01) for the two SNPs. No significant effect was observed in the GESBC study. These studies showed that two SNPs in the COMT distal promoter were associated with breast cancer risk reduction in two of three case control studies, compatible with the results of functional genomic experiments, suggesting a role for MB-COMT in breast cancer risk. [Cancer Res 2008;68(14):5997–6005]
Data from PTEN Has Tumor-Promoting Properties in the Setting of Gain-of-Function p53 Mutations
Authors: Li Yunqing , Guessous Fadila , Kwon Sherwin , Kumar Manish , Ibidapo Opeyemi , Fuller Lauren , Johnson Elizabeth , Lal Bachchu , Hussaini Isa , Bao Yongde , Laterra John , Schiff David , Abounader Roger
Published: March 2023

Abstract
We show, for the first time, that the tumor suppressor PTEN can have tumor-promoting properties. We show that PTEN acquires these unexpected properties by enhancing gain-of-function mutant p53 (mut-p53) protein levels. We find that PTEN restoration to cells harboring mut-p53 leads to induction of G1-S cell cycle progression and cell proliferation and to inhibition of cell death. Conversely, PTEN inhibition in cells expressing wild-type PTEN and mut-p53 leads to inhibition of cell proliferation and inhibition of in vivo tumor growth. We show the dependency of the tumor-promoting effects of PTEN on mut-p53 by showing that knockdown of mut-p53 expression inhibits or reverses the tumor-promoting effects of PTEN. Mechanistically, we show that PTEN expression enhances mut-p53 protein levels via inhibition of mut-p53 degradation by Mdm2 and possibly also via direct protein binding. These findings describe a novel function of PTEN and have important implications for experimental and therapeutic strategies that aim at manipulating PTEN or p53 in human tumors. They suggest that the mutational status of PTEN and p53 should be considered to achieve favorable therapeutic outcomes. The findings also provide an explanation for the low frequency of simultaneous mutations of PTEN and p53 in human cancer. [Cancer Res 2008;68(6):1723–31]
Data from The Previously Undescribed ZKSCAN3 (ZNF306) Is a Novel “Driver” of Colorectal Cancer Progression
Authors: Yang Lin , Hamilton Stanley R. , Sood Anil , Kuwai Toshio , Ellis Lee , Sanguino Angela , Lopez-Berestein Gabriel , Boyd Douglas D.
Published: March 2023

Abstract
A relatively new view of colorectal cancer is that its development/progression reflects the contribution of a large set of altered gene products in varying combinations, each providing a “fitness advantage.” In searching for novel contributing gene products using Unigene cluster data mining, we found overrepresentation of expressed sequence tags corresponding to a previously uncharacterized gene (ZKSCAN3) in colorectal tumors. ZKSCAN3 was pursued for several reasons: (a) its sequence similarity with bowl required for Drosophila hindgut development; (b) it lies in a chromosomal region (6p22.1) amplified in colorectal cancer; and (c) its coding sequence predicts tandem C2H2 zinc finger domains present in a class of proteins gaining attention for their role in oncogenesis/tumor progression. Reverse transcription-PCR confirmed overexpression in colorectal tumor tissue compared with adjacent nonmalignant mucosa due in part to gene amplification determined by Southern blotting. Further, immunohistochemistry with an antibody generated to the predicted protein sequence revealed higher ZKSCAN3 expression in invasive compared with noninvasive tumors. Intriguingly, the ZKSCAN3 protein was also expressed in tumors wild-type for genes (APC, p53, K-Ras) commonly targeted in colorectal cancer. ZKSCAN3 knockdown in two independent colon cancer cell lines impaired anchorage-independent growth and orthotopic tumor growth, whereas overexpression in a third cell line had the opposite effect and increased 5-fluorouracil resistance. Liposomal delivery of a ZKSCAN3-targeting small interfering RNA reduced tumorigenicity of orthotopic colon cancer. Thus, the hitherto uncharacterized ZKSCAN3 adds to an expanding set of encoded products contributing to the progression of colorectal cancer. [Cancer Res 2008;68(11):4321–30]
Data from Amyloid Precursor Protein Is a Primary Androgen Target Gene That Promotes Prostate Cancer Growth
Authors: Takayama Ken-ichi , Tsutsumi Shuichi , Suzuki Takashi , Horie-Inoue Kuniko , Ikeda Kazuhiro , Kaneshiro Kiyofumi , Fujimura Tetsuya , Kumagai Jinpei , Urano Tomohiko , Sakaki Yoshiyuki , Shirahige Katsuhiko , Sasano Hironobu , Takahashi Satoru , Kitamura Tadaichi , Ouchi Yasuyoshi , Aburatani Hiroyuki , Inoue Satoshi
Published: March 2023

Abstract
Androgen receptor (AR) is a critical transcription factor that regulates various target genes and contributes to the pathophysiology of prostate cancer hormone dependently. Here, we identify amyloid precursor protein (APP) as a primary androgen target through chromatin immunoprecipitation (ChIP) combined with genome tiling array analysis (ChIP-chip). ChIP-treated DNA were obtained from prostate cancer LNCaP cells with R1881 or vehicle treatment using AR or acetylated histone H3 antibodies. Ligand-dependent AR binding was further enriched by PCR subtraction. Using chromosome 21/22 arrays, we identified APP as one of the androgen-regulated genes with adjacent functional AR binding sites. APP expression is androgen-inducible in LNCaP cells and APP immunoreactivity was correlated with poor prognosis in patients with prostate cancer. Gain-of-function and loss-of-function studies revealed that APP promotes the tumor growth of prostate cancer. The present study reveals a novel APP-mediated pathway responsible for the androgen-dependent growth of prostate cancer. Our findings will indicate that APP could be a potential molecular target for the diagnosis and treatment of prostate cancer. [Cancer Res 2009;69(1):137–42]
Data from Role of Cyclin D1 as a Mediator of c-Met– and β-Catenin–Induced Hepatocarcinogenesis
Authors: Patil Mohini A. , Lee Susie A. , Macias Everardo , Lam Ernest T. , Xu Chuanrui , Jones Kirk D. , Ho Coral , Rodriguez-Puebla Marcelo , Chen Xin
Published: March 2023

Abstract
Activation of c-Met signaling and β-catenin mutations are frequent genetic events observed in liver cancer development. Recently, we demonstrated that activated β-catenin can cooperate with c-Met to induce liver cancer formation in a mouse model. Cyclin D1 (CCND1) is an important cell cycle regulator that is considered to be a downstream target of β-catenin. To determine the importance of CCND1 as a mediator of c-Met– and β-catenin–induced hepatocarcinogenesis, we investigated the genetic interactions between CCND1, β-catenin, and c-Met in liver cancer development using mouse models. We coexpressed CCND1 with c-Met in mice and found CCND1 to cooperate with c-Met to promote liver cancer formation. Tumors induced by CCND1/c-Met had a longer latency period, formed at a lower frequency, and seemed to be more benign compared with those induced by β-catenin/c-Met. In addition, when activated β-catenin and c-Met were coinjected into CCND1-null mice, liver tumors developed despite the absence of CCND1. Intriguingly, we observed a moderate accelerated tumor growth and increased tumor malignancy in these CCND1-null mice. Molecular analysis showed an up-regulation of cyclin D2 (CCND2) expression in CCND1-null tumor samples, indicating that CCND2 may replace CCND1 in hepatic tumorigenesis. Together, our results suggest that CCND1 functions as a mediator of β-catenin during HCC pathogenesis, although other molecules may be required to fully propagate β-catenin signaling. Moreover, our data suggest that CCND1 expression is not essential for liver tumor development induced by c-Met and β-catenin. [Cancer Res 2009;69(1):253–61]
Data from Bacterial Cytosine Deaminase Mutants Created by Molecular Engineering Show Improved 5-Fluorocytosine–Mediated Cell Killing In vitro and In vivo
Authors: Fuchita Michi , Ardiani Andressa , Zhao Lei , Serve Kinta , Stoddard Barry L. , Black Margaret E.
Published: March 2023

Abstract
Cytosine deaminase is used in combination with 5-fluorocytosine as an enzyme-prodrug combination for targeted genetic cancer treatment. This approach is limited by inefficient gene delivery and poor prodrug conversion activities. Previously, we reported individual point mutations within the substrate binding pocket of bacterial cytosine deaminase (bCD) that result in marginal improvements in the ability to sensitize cells to 5-fluorocytosine (5FC). Here, we describe an expanded random mutagenesis and selection experiment that yielded enzyme variants, which provide significant improvement in prodrug sensitization. Three of these mutants were evaluated using enzyme kinetic analyses and then assayed in three cancer cell lines for 5FC sensitization, bystander effects, and formation of 5-fluorouracil metabolites. All variants displayed 18- to 19-fold shifts in substrate preference toward 5FC, a significant reduction in IC50 values and improved bystander effect compared with wild-type bCD. In a xenograft tumor model, the best enzyme mutant was shown to prevent tumor growth at much lower doses of 5FC than is observed when tumor cells express wild-type bCD. Crystallographic analyses of this construct show the basis for improved activity toward 5FC, and also how two different mutagenesis strategies yield closely related but mutually exclusive mutations that each result in a significant alteration of enzyme specificity. [Cancer Res 2009;69(11):4791–9]
Data from [18F]Fluoromethyl-[1,2-2H4]-Choline: A Novel Radiotracer for Imaging Choline Metabolism in Tumors by Positron Emission Tomography
Authors: Leyton Julius , Smith Graham , Zhao Yongjun , Perumal Meg , Nguyen Quang-De , Robins Edward , Årstad Erik , Aboagye Eric O.
Published: March 2023

Abstract
Current radiotracers for positron emission tomography imaging of choline metabolism have poor systemic metabolic stability in vivo. We describe a novel radiotracer, [18F]fluoromethyl-[1,2-2H4]-choline (D4-FCH), that employs deuterium isotope effect to improve metabolic stability. D4-FCH proved more resistant to oxidation than its nondeuterated analogue, [18F]fluoromethylcholine, in plasma, kidneys, liver, and tumor, while retaining phosphorylation potential. Tumor radiotracer levels, a determinant of sensitivity in imaging studies, were improved by deuterium substitution; tumor uptake values expressed as percent injected dose per voxel at 60 min were 7.43 ± 0.47 and 5.50 ± 0.49 for D4-FCH and [18F]fluoromethylcholine, respectively (P = 0.04). D4-FCH was also found to be a useful response biomarker. Treatment with the mitogenic extracellular kinase inhibitor PD0325901 resulted in a reduction in tumor radiotracer uptake that occurred in parallel with reductions in choline kinase A expression. In conclusion, D4-FCH is a very promising metabolically stable radiotracer for imaging choline metabolism in tumors. [Cancer Res 2009;69(19):7721–8]
Data from Haploinsufficiency of Krüppel-Like Factor 5 Rescues the Tumor-Initiating Effect of the ApcMin Mutation in the Intestine
Authors: McConnell Beth B. , Bialkowska Agnieszka B. , Nandan Mandayam O. , Ghaleb Amr M. , Gordon Frank J. , Yang Vincent W.
Published: March 2023

Abstract
Inactivation of the tumor suppressor adenomatous polyposis coli, with the resultant activation of β-catenin, is the initiating event in the development of a majority of colorectal cancers. Krüppel-like factor 5 (KLF5), a proproliferative transcription factor, is highly expressed in the proliferating intestinal crypt epithelial cells. To determine whether KLF5 contributes to intestinal adenoma formation, we examined tumor burdens in ApcMin/+ mice and ApcMin/+/Klf5+/− mice. Compared with ApcMin/+ mice, ApcMin/+/Klf5+/− mice had a 96% reduction in the number of intestinal adenomas. Reduced tumorigenicity in the ApcMin/+/Klf5+/− mice correlated with reduced levels and nuclear localization of β-catenin as well as reduced expression of two β-catenin targets, cyclin D1 and c-Myc. In vitro studies revealed a physical interaction between KLF5 and β-catenin that enhanced the nuclear localization and transcriptional activity of β-catenin. Thus, KLF5 is necessary for the tumor-initiating activity of β-catenin during intestinal adenoma formation in ApcMin/+ mice, and reduced expression of KLF5 offsets the tumor-initiating activity of the ApcMin mutation by reducing the nuclear localization and activity of β-catenin. [Cancer Res 2009;69(10):4125–33]
Data from Breast Cancer Migration and Invasion Depend on Proteasome Degradation of Regulator of G-Protein Signaling 4
Authors: Xie Yan , Wolff Dennis W. , Wei Taotao , Wang Bo , Deng Caishu , Kirui Joseph K. , Jiang Haihong , Qin Jianbing , Abel Peter W. , Tu Yaping
Published: March 2023

Abstract
Aberrant signaling through G-protein coupled receptors promotes metastasis, the major cause of breast cancer death. We identified regulator of G-protein signaling 4 (RGS4) as a novel suppressor of breast cancer migration and invasion, important steps of metastatic cascades. By blocking signals initiated through Gi-coupled receptors, such as protease-activated receptor 1 and CXC chemokine receptor 4, RGS4 disrupted Rac1-dependent lamellipodia formation, a key step involved in cancer migration and invasion. RGS4 has GTPase-activating protein (GAP) activity, which inhibits G-protein coupled receptor signaling by deactivating G-proteins. An RGS4 GAP-deficient mutant failed to inhibit migration and invasion of breast cancer cells in both in vitro assays and a mouse xenograft model. Interestingly, both established breast cancer cell lines and human breast cancer specimens showed that the highest levels of RGS4 protein were expressed in normal breast epithelia and that RGS4 down-regulation by proteasome degradation is an index of breast cancer invasiveness. Proteasome blockade increased endogenous RGS4 protein to levels that markedly inhibit breast cancer cell migration and invasion, which was reversed by an RGS4-targeted short hairpin RNA. Our findings point to the existence of a mechanism for posttranslational regulation of RGS4 function, which may have important implications for the acquisition of a metastatic phenotype by breast cancer cells. Preventing degradation of RGS4 protein should attenuate aberrant signal inputs from multiple Gi-coupled receptors, thereby retarding the spread of breast cancer cells and making them targets for surgery, radiation, and immune treatment. [Cancer Res 2009;69(14):5743–51]
Data from Cell Type–Specific Targeted Mutations of Kras and Pten Document Proliferation Arrest in Granulosa Cells versus Oncogenic Insult to Ovarian Surface Epithelial Cells
Authors: Fan Heng-Yu , Liu Zhilin , Paquet Marilene , Wang Jinrong , Lydon John P. , DeMayo Francesco J. , Richards JoAnne S.
Published: March 2023

Abstract
The small G-protein KRAS is crucial for mediating gonadotropin-induced events associated with ovulation. However, constitutive expression of KrasG12D in granulosa cells disrupted normal follicle development leading to the persistence of abnormal follicle-like structures containing nonmitotic cells. To determine what factors mediate this potent effect of KrasG12D, gene profiling analyses were done. We also analyzed KrasG12D;Cyp19-Cre and KrasG12;Pgr-Cre mutant mouse models that express Cre prior to or after the initiation of granulosa cell differentiation, respectively. KrasG12D induced cell cycle arrest in granulosa cells of the KrasG12D;Cyp19-Cre mice but not in the KrasG12D;Pgr-Cre mice, documenting the cell context–specific effect of KrasG12D. Expression of KrasG12D silenced the Kras gene, reduced cell cycle activator genes, and impaired the expression of granulosa cell and oocyte-specific genes. Conversely, levels of PTEN and phosphorylated p38 mitogen-activated protein kinase (MAPK) increased markedly in the mutant granulosa cells. Because disrupting Pten in granulosa cells leads to increased proliferation and survival, Pten was disrupted in the KrasG12D mutant mice. The Pten/Kras mutant mice were infertile but lacked granulosa cell tumors. By contrast, the Ptenfl/fl;KrasG12D;Amhr2-Cre mice developed aggressive ovarian surface epithelial cell tumors that did not occur in the Ptenfl/fl;KrasG12D;Cyp19-Cre or Ptenfl/fl;KrasG12D;Pgr-Cre mouse strains. These data document unequivocally that Amhr2-Cre is expressed in and mediates allelic recombination of oncogenic genes in ovarian surface epithelial cells. That KrasG12D/Pten mutant granulosa cells do not transform but rather undergo cell cycle arrest indicates that they resist the oncogenic insults of Kras/Pten by robust self-protecting mechanisms that silence the Kras gene and elevate PTEN and phosphorylated p38 MAPK. [Cancer Res 2009;69(16):6463–72]
Data from 17-Hydroxy-jolkinolide B Inhibits Signal Transducers and Activators of Transcription 3 Signaling by Covalently Cross-Linking Janus Kinases and Induces Apoptosis of Human Cancer Cells
Authors: Wang Ying , Ma Xiuquan , Yan Shousheng , Shen Shensi , Zhu Huiling , Gu Yuan , Wang Hongbing , Qin Guowei , Yu Qiang
Published: March 2023

Abstract
Constitutive activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway occurs frequently in cancer cells and contributes to oncogenesis. Among the members of STAT family, STAT3 plays a pivotal role in the development and progression of human tumors. The STAT3-mediated signaling pathway has been recognized as a promising anticancer target. Here, we show that 17-Hydroxy-jolkinolide B (HJB), a diterpenoid from the Chinese medicinal herb Euphorbia fischeriana Steud, strongly inhibits interleukin (IL)-6–induced as well as constitutive STAT3 activation. Furthermore, we show that HJB directly targets the JAK family kinases, JAK1, JAK2, and TYK2, by inducing dimerization of the JAKs via cross-linking. Addition of DTT or glutathione prevents the JAK cross-linking and blocks the inhibitory effects of HJB on IL-6–induced STAT3 activation, suggesting that HJB may react with cystein residues of JAKs to form covalent bonds that inactivate JAKs. Liquid chromatography/mass spectrometry analysis confirmed that each HJB reacted with two thiols. The effect of HJB on the JAK/STAT3 pathway is specific as HJB has no effect on platelet-derived growth factor, epidermal growth factor, or insulin-like growth factor I signaling pathways. Finally, we show that HJB inhibits growth and induces apoptosis of tumor cells, particularly those tumor cells with constitutively activated STAT3. We propose that the natural compound HJB is a promising anticancer drug candidate as a potent STAT3 signaling inhibitor. [Cancer Res 2009;69(18):7302–10]
Data from Genome-Wide Linkage Analysis of TMPRSS2-ERG Fusion in Familial Prostate Cancer
Authors: Hofer Matthias D. , Kuefer Rainer , Maier Christiane , Herkommer Kathleen , Perner Sven , Demichelis Francesca , Paiss Thomas , Vogel Walter , Rubin Mark A. , Hoegel Josef
Published: March 2023

Abstract
Fusion of the 5′-untranslated region of androgen-regulated TMPRSS2 promoter with ETS transcription factor family members is found frequently in prostate cancers, and recent work suggests that the most common TMPRSS2-ERG fusion is associated with an aggressive clinical phenotype compared with fusion-negative prostate cancer. Thus far, analysis of the fusion has been limited to sporadic cases of prostate cancer. In the current study, we explore for an enrichment of TMPRSS2-ERG fusion in familial prostate cancer. TMPRSS2-ERG fusion was identified using a break-apart fluorescence in situ hybridization assay on tissue microarrays. Presence of TMPRSS2-ERG fusion was associated with higher Gleason scores (P = 0.027). Of 75 patients with established history of prostate cancer, we detected the TMPRSS2-ERG fusion in 44 (59%) patients. Almost three quarters (73%) of fusion-positive patients accumulated within 16 specific families whereas only 27% were single fusion-positive cases within one family. Based on reported prevalence rates, we calculated a sibling recurrence risk ratio of up to 18.9. A subset (63%) of families with uniformly TMPRSS2-ERG–positive prostate cancer underwent a genome-wide linkage scan at 500 markers. This revealed several loci located on chromosomes #9, #18, and X that were suggestive of linkage to the TMPRSS2-ERG fusion-positive prostate cancer phenotype with linkage-of-disease scores up to 2.16 and nonparametric linkage scores up to 2.77. This suggests the presence of an inherited susceptibility to developing the TMPRSS2-ERG fusion. Given the association of TMPRSS2-ERG fusion and aggressive prostate cancer, close surveillance of relatives of patients with established fusion-positive prostate cancer or a family history of prostate cancer in general would be warranted. [Cancer Res 2009;69(4):640–6]
Data from Transcript Level Modulates the Inherent Oncogenicity of RET/PTC Oncoproteins
Authors: Richardson Douglas S. , Gujral Taranjit S. , Peng Susan , Asa Sylvia L. , Mulligan Lois M.
Published: March 2023

Abstract
Mutations to the RET proto-oncogene occur in as many as one in three cases of thyroid cancer and have been detected in both the medullary (MTC) and the papillary (PTC) forms of the disease. Of the nearly 400 chromosomal rearrangements resulting in oncogenic fusion proteins that have been identified to date, the rearrangements that give rise to RET fusion oncogenes in PTC remain the paradigm for chimeric oncoprotein involvement in solid tumors. RET-associated PTC tumors are phenotypically indolent and relatively less aggressive than RET-related MTCs. The mechanism(s) contributing to the differences in oncogenicity of RET-related MTC and PTC remains unexplained. Here, through cellular and molecular characterization of the two most common RET/PTC rearrangements (PTC1 and PTC3), we show that RET/PTC oncoproteins are highly oncogenic when overexpressed, with the ability to increase cell proliferation and transformation. Further, RET/PTCs activate similar downstream signaling cascades to wild-type RET, although at different levels, and are relatively more stable as they avoid lysosomal degradation. Absolute quantitation of transcript levels of RET, CCDC6, and NCOA4 (the 5′ fusion genes involved in PTC1 and PTC3, respectively) suggest that these rearrangements result in lower RET expression in PTCs relative to MTCs. Together, our findings suggest PTC1 and PTC3 are highly oncogenic proteins when overexpressed, but result in indolent disease compared with RET-related MTCs due to their relatively low expression from the NCOA4 and CCDC6 promoters in vivo. [Cancer Res 2009;69(11):4861–9]
Data from Deciphering the Impact of Common Genetic Variation on Lung Cancer Risk: A Genome-Wide Association Study
Authors: Broderick Peter , Wang Yufei , Vijayakrishnan Jayaram , Matakidou Athena , Spitz Margaret R. , Eisen Timothy , Amos Christopher I. , Houlston Richard S.
Published: March 2023

Abstract
To explore the impact of common variation on the risk of developing lung cancer, we conducted a two-phase genome-wide association (GWA) study. In phase 1, we compared the genotypes of 511,919 tagging single nucleotide polymorphisms (SNP) in 1,952 cases and 1,438 controls; in phase 2, 30,568 SNPs were genotyped in 2,465 cases and 3,005 controls. SNP selection was based on best supported P values from phase 1 and two other GWA studies of lung cancer. In the combined analysis of phases 1 and 2, the strongest associations identified were defined by SNPs mapping to 15q25.1 (rs12914385; P = 3.19 × 10−16), 5p15.33 (rs4975616; P = 6.66 × 10−7), and 6p21.33 (rs3117582; P = 9.13 × 10−7). Variation at 15q25.1, but not 5p15.33 or 6p21.33, was strongly associated with smoking behavior with risk alleles correlated to higher consumption. Variation at 5p15.33 was shown to significantly influence induction of lung cancer histology. Pooling data from the four series provided 21,620 genotypes for 7,560 cases and 8,205 controls. A meta-analysis provided increased support that variation at 15q25.1 (rs8034191; P = 3.24 × 10−26), 5p15.33 (rs4975616; P = 2.99 × 10−9), and 6p21.33 (rs3117582; P = 4.46 × 10−10) influences lung cancer risk. The next best-supported associations were attained at 15q15.2 (rs748404: P = 1.08 × 10−6) and 10q23.31 (rs1926203; P = 1.28 × 10−6). These data indicate few common variants account for 1% of the excess familial risk underscoring the necessity of having additional large sample series for gene discovery. [Cancer Res 2009;69(16):6633–41]
Data from PUMA Suppresses Intestinal Tumorigenesis in Mice
Authors: Qiu Wei , Carson-Walter Eleanor B. , Kuan Shih Fan , Zhang Lin , Yu Jian
Published: March 2023

Abstract
Defective apoptosis contributes to tumorigenesis, although the critical molecular targets remain to be fully characterized. PUMA, a BH3-only protein essential for p53-dependent apoptosis, has been shown to suppress lymphomagenesis. In this study, we investigated the role of PUMA in intestinal tumorigenesis using two animal models. In the azoxymethane (AOM)/dextran sulfate sodium salt model, PUMA deficiency increased the multiplicity and size of colon tumors but reduced the frequency of β-catenin hotspot mutations. The absence of PUMA led to a significantly elevated incidence of precursor lesions induced by AOM. AOM was found to induce p53-dependent PUMA expression and PUMA-dependent apoptosis in the colonic crypts and stem cell compartment. Furthermore, PUMA deficiency significantly enhanced the formation of spontaneous macroadenomas and microadenomas in the distal small intestine and colon of APCMin/+ mice. These results show an essential role of PUMA-mediated apoptosis in suppressing intestinal tumorigenesis in mice. [Cancer Res 2009;69(12):4999–5006]