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Association of CCND1 overexpression with KRAS and PTEN alterations in specific subtypes of non-small cell lung carcinoma and its influence on patients' outcome. Tumour Biol 2015; 36:8773-80. [PMID: 26055143 DOI: 10.1007/s13277-015-3620-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 05/27/2015] [Indexed: 01/12/2023] Open
Abstract
Cyclin D1 is one of the major cellular oncogenes, overexpressed in number of human cancers, including non-small cell lung carcinoma (NSCLC). However, it does not exert tumorigenic activity by itself, but rather cooperates with other altered oncogenes and tumor suppressors. Therefore, in the present study, we have examined mutual role of cyclin D1, KRAS, and PTEN alterations in the pathogenesis of NSCLC and their potential to serve as multiple molecular markers for this disease. CCND1 gene amplification and gene expression were analyzed in relation to mutational status of KRAS gene as well as to PTEN alterations (loss of heterozygosity and promoter hypermethylation) in NSCLC patient samples. Moreover, the effect of these co-alterations on patient survival was examined. Amplified CCND1 gene was exclusively associated with increased gene expression. Statistical analyses also revealed significant association between CCND1 overexpression and KRAS mutations in the whole group and in the groups of patients with adenocarcinoma, grade 1/2, and stage I/II. In addition, CCND1 overexpression was significantly related to PTEN promoter hypermethylation in the whole group and in the group of patients with squamous cell carcinoma and lymph node invasion. These joint alterations also significantly shortened patients' survival and were shown to be an independent factor for adverse prognosis. Overall results point that cyclin D1 expression cooperates with KRAS and PTEN alterations in pathogenesis of NSCLC, and they could serve as potential multiple molecular markers for specific subgroups of NSCLC patients as well as prognostic markers for this type of cancer.
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Yeh ES, Vernon-Grey A, Martin H, Chodosh LA. Tetracycline-regulated mouse models of cancer. Cold Spring Harb Protoc 2014; 2014:pdb.top069823. [PMID: 25275112 DOI: 10.1101/pdb.top069823] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Genetically engineered mouse models (GEMMs) have proven essential to the study of mammalian gene function in both development and disease. However, traditional constitutive transgenic mouse model systems are limited by the temporal and spatial characteristics of the experimental promoter used to drive transgene expression. To address this limitation, considerable effort has been dedicated to developing conditional and inducible mouse model systems. Although a number of approaches to generating inducible GEMMs have been pursued, several have been restricted by toxic or undesired physiological side effects of the compounds used to activate gene expression. The development of tetracycline (tet)-dependent regulatory systems has allowed for circumvention of these issues resulting in the widespread adoption of these systems as an invaluable tool for modeling the complex nature of cancer progression.
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Affiliation(s)
- Elizabeth S Yeh
- Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104; Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Ann Vernon-Grey
- Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104; Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Heather Martin
- Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104; Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Lewis A Chodosh
- Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104; Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104; Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104; Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
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Krishnan B, Torti FM, Gallagher PE, Tallant EA. Angiotensin-(1-7) reduces proliferation and angiogenesis of human prostate cancer xenografts with a decrease in angiogenic factors and an increase in sFlt-1. Prostate 2013; 73:60-70. [PMID: 22644934 DOI: 10.1002/pros.22540] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 04/20/2012] [Indexed: 12/27/2022]
Abstract
BACKGROUND Prostate cancer is the most frequently diagnosed malignancy and the second-leading cause of cancer death in men. The purpose of this study was to determine the anti-proliferative and anti-angiogenic efficacy of angiotensin-(1-7) [Ang-(1-7)], an endogenous peptide hormone, in human prostate cancer xenografts. METHODS Human LNCaP prostate cancer cells were injected into the flank of athymic mice and tumors were treated with Ang-(1-7) for 54 days. Tumor growth and angiogenesis were determined by immunohistochemistry and western blot hybridization. RESULTS Ang-(1-7) markedly reduced the volume and wet weight of LNCaP xenograft tumors. Histological analysis of tumor sections from saline-treated mice showed increased Ki67 immunoreactivity and enhanced phosphorylation of the MAP kinases ERK1/2 compared to tumors from Ang-(1-7)-treated mice, suggesting that the heptapeptide reduces cell proliferation. Intratumoral vessel density was decreased in Ang-(1-7)-treated mice with an associated reduction in vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), suggesting that the heptapeptide attenuates vascularization by reducing angiogenic factors. Ang-(1-7) administration markedly increased the soluble fraction of VEGF receptor 1 (sFlt-1), with a concomitant reduction in VEGF receptors 1 and 2. sFlt-1 serves as a decoy receptor that traps VEGF and PlGF, making the ligands unavailable to membrane-bound VEGF receptors and preventing activation of pro-angiogenic signaling. CONCLUSIONS The decrease in PlGF and VEGF coupled with the increase in sFlt-1 suggests that Ang-(1-7) may serve as a novel anti-angiogenic therapy for prostate cancer. Further, the pleiotropic mechanisms of action by Ang-(1-7) may limit angiogenic resistance that occurs with VEGF inhibitors or receptor blockers.
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Affiliation(s)
- Bhavani Krishnan
- Hypertension and Vascular Research Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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Association between survivin -31G > C promoter polymorphism and cancer risk: a meta-analysis. Eur J Hum Genet 2012; 20:790-5. [PMID: 22274581 DOI: 10.1038/ejhg.2011.276] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Survivin is an inhibitor of apoptosis protein and has a crucial role in the development of cancer. The survivin -31G>C (rs9904341) promoter polymorphism influences survivin expression and has been implicated in cancer risk. However, conflicting results have been published from studies on the association between survivin -31G>C polymorphism and the risk of cancer. To clarify the role of this polymorphism in cancer, we performed a meta-analysis of all available and relevant published studies, involving a total of 3485 cancer patients and 3964 control subjects. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. The overall results indicated that the variant genotypes were associated with a significantly increased cancer risk (CC vs GG: OR=1.58, 95% CI=1.20-2.10; CC/GC vs GG: OR=1.23, 95% CI=1.00-1.51; CC vs GG/GC: OR=1.51, 95% CI=1.23-1.85). In the stratified analyses, significantly increased risk was associated with the Asian populations (CC vs GG: OR=1.67, 95% CI=1.16-2.40; CC vs GG/GC: OR=1.50, 95% CI=1.17-1.91). We also performed the analyses by cancer type, and no statistical association was observed. The results suggest that the survivin -31G>C promoter polymorphism might be associated with an increased risk of cancer, especially in the Asian populations.
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Miller MS, Miller LD. RAS Mutations and Oncogenesis: Not all RAS Mutations are Created Equally. Front Genet 2012; 2:100. [PMID: 22303394 PMCID: PMC3262225 DOI: 10.3389/fgene.2011.00100] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 12/13/2011] [Indexed: 12/28/2022] Open
Abstract
Mutation in RAS proteins is one of the most common genetic alterations observed in human and experimentally induced rodent cancers. In vivo, oncogenic mutations have been shown to occur at exons 12, 13, and 61, resulting in any 1 of 19 possible point mutations in a given tumor for a specific RAS isoform. While some studies have suggested a possible role of different mutant alleles in determining tumor severity and phenotype, no general consensus has emerged on the oncogenicity of different mutant alleles in tumor formation and progression. Part of this may be due to a lack of a single, signature pathway that shows significant alterations between different mutations. Rather, it is likely that subtle differences in the activation, or lack thereof, of downstream effectors by different RAS mutant alleles may determine the eventual outcome in terms of tumor phenotype. This paper reviews our current understanding of the potential role of different RAS mutations on tumorigenesis, highlights studies in model cell culture and in vivo systems, and discusses the potential of expression array and computational network modeling to dissect out differences in activated RAS genes in conferring a transforming phenotype.
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Affiliation(s)
- Mark Steven Miller
- Department of Cancer Biology, Comprehensive Cancer Center, Wake Forest School of MedicineWinston-Salem, NC, USA
| | - Lance D. Miller
- Department of Cancer Biology, Comprehensive Cancer Center, Wake Forest School of MedicineWinston-Salem, NC, USA
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Cui PH, Petrovic N, Murray M. The ω-3 epoxide of eicosapentaenoic acid inhibits endothelial cell proliferation by p38 MAP kinase activation and cyclin D1/CDK4 down-regulation. Br J Pharmacol 2011; 162:1143-55. [PMID: 21077851 DOI: 10.1111/j.1476-5381.2010.01113.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND AND PURPOSE Dietary intake of ω-3 polyunsaturated fatty acids (ω-3 PUFAs) like eicosapentaenoic acid (EPA) decreases cancer risk, while arachidonic acid and other ω-6 PUFAs increase risk, but the underlying mechanisms are unclear. Cytochrome P450 (CYP)-derived epoxides contribute to enhanced tumourigenesis due to ω-6 PUFA intake. Thus, ω-6 arachidonic acid epoxides (EETs) inhibit apoptosis and stimulate proliferation by up-regulating cyclin D1 expression in cells. The present study evaluated the corresponding ω-3 PUFA epoxides and assessed their role in the regulation of cell proliferation. EXPERIMENTAL APPROACH Four chemically stable EPA epoxides (formed at the 8,9-, 11,12-, 14,15- and 17,18-olefinic bonds) were synthesized and tested against growth-related signalling pathways in brain microvascular endothelial bEND.3 cells. Cell cycle distribution was determined by flow cytometry and cyclin gene expression by immunoblotting and real-time PCR. The role of the p38 mitogen-activated protein (MAP) kinase in cyclin D1 dysregulation was assessed using specific inhibitors and dominant-negative expression plasmids. KEY RESULTS The ω-3 17,18-epoxide of EPA decreased cell proliferation, interrupted the cell cycle in S-phase and down-regulated the cyclin D1/cyclin-dependent kinase (CDK)-4 complex, whereas the 8,9-, 11,12- and 14,15-epoxides were either inactive or enhanced proliferation. Cyclin D1 down-regulation by 17,18-epoxy-EPA was mediated by activation of the growth-suppressing p38 MAP kinase, but the alternate EPA-epoxides were inactive. CONCLUSIONS AND IMPLICATIONS The present findings suggest that the epoxide formed by CYP enzymes at the ω-3 olefinic bond may contribute to the beneficial effects of ω-3 PUFA by down-regulating cyclin D1 and suppressing cell proliferation.
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Affiliation(s)
- Pei H Cui
- Pharmacogenomics and Drug Development Group, Faculty of Pharmacy, University of Sydney, New South Wales, Australia
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Prognostic significance of survivin polymorphisms on non-small cell lung cancer survival. J Thorac Oncol 2011; 5:1748-54. [PMID: 20881643 DOI: 10.1097/jto.0b013e3181f18cb9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Survivin is an apoptotic inhibitor, involves in regulation of apoptosis and cell cycle progression, and its polymorphisms may influence the development and progression of cancer. This study evaluated the impact of the survivin gene polymorphisms on survival of non-small cell lung cancer (NSCLC) patients. METHODS In this case-cohort follow-up study, a total of 568 NSCLC patients were investigated and 12 single nucleotide polymorphisms in survivin gene were genotyped by using the Illumina GoldenGate platform. RESULTS During the maximum of 72 months of follow-up, 314 (55.11%) deaths were observed. After adjusting for age, gender, smoking status, histology, stage, surgical operation, and chemotherapy or radiotherapy status, Cox hazard proportional model suggested that four single nucleotide polymorphisms had statistically significant impacts on NSCLC survival (rs3764383, AG/GG versus AA, hazard ratio [HR] = 0.78, 95% confidence interval [CI]: 0.62-0.99; rs8073069, GG versus CG/CC, HR = 1.76, 95% CI: 1.16-2.67; rs4789551, GG versus AG/AA, HR = 2.04, 95% CI: 1.08-3.86; rs1042489, GG versus AG/AA, HR = 1.37, 95% CI: 1.03-1.83). Further combined analysis showed that the high risk group (3-4 unfavorable loci) presented a 1.84-fold (95% CI: 1.22-2.77) increased risk compared with low risk group (0-2 unfavorable loci). Among 185 stage III to IV patients who received only chemotherapy, only the potentially functional rs8073069 still had a significantly increased risk on the prognosis of NSCLC (GG versus CG/CC, HR = 2.06, 95% CI: 1.10-3.87). CONCLUSIONS Our results suggest that polymorphisms in survivin may be a genetic modifier for NSCLC prognosis in this Chinese population.
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Floyd HS, Chen LC, Vallanat B, Dreher K. Fine ambient air particulate matter exposure induces molecular alterations associated with vascular disease progression within plaques of atherosclerotic susceptible mice. Inhal Toxicol 2010; 21:394-403. [PMID: 19496694 DOI: 10.1080/08958370802317745] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Epidemiology studies have reported associations between increased mortality and morbidity with exposure to particulate air pollution, particularly within individuals with preexisting cardiovascular disease (CVD). Clinical and toxicological studies have provided evidence that exposure to ambient air particulate matter (PM) impacts CVD by increasing plaque size. It is unclear whether PM-induced increased plaque size is associated with molecular disease progression. This study examines molecular profiles within plaques recovered from ApoE(-/-) mice exposed to concentrated ambient air particles (CAPs) to determine whether pulmonary deposition of PM contributes to molecular alterations leading to vascular disease progression. Laser capture microdissection was used to recover atherosclerotic plaques from ApoE(-/-) male mice exposed daily for 5 mo to filtered air or CAPs. Alterations in mRNA expression was assessed in microdissected plaques of CAPs-exposed and air controls using the Affymetrix microarray platform. Bioinformatic analysis indicated alterations in 611 genes: 395 genes downregulated and 216 genes upregulated. Gene ontology revealed CAPs-induced changes to inflammation, proliferation, cell cycle, hematological system, and cardiovascular pathways. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) verified microarray data also revealing gene expression alterations undetected by the microarray analysis, i.e., decreased expression of alpha-actin for smooth muscle cells, and increased expression of the macrophage marker Cd68 and of beta-actin. Comparison of CAPs-induced gene expression profiles demonstrated consistency with previously published gene expression profiles in the ApoE(-/-) mouse model and humans associated with plaque progression. These results indicate that exposure to fine PM induces molecular alterations associated with vascular disease progression and provides insight into potential biological pathways responsible for this effect.
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Affiliation(s)
- Heather S Floyd
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA
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Kim WY, Jin Q, Oh SH, Kim ES, Yang YJ, Lee DH, Feng L, Behrens C, Prudkin L, Miller YE, Lee JJ, Lippman SM, Hong WK, Wistuba II, Lee HY. Elevated epithelial insulin-like growth factor expression is a risk factor for lung cancer development. Cancer Res 2009; 69:7439-48. [PMID: 19738076 DOI: 10.1158/0008-5472.can-08-3792] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Insulin-like growth factor (IGF)-I receptor (IGF-IR) signaling has been implicated in several human neoplasms. However, the role of serum levels of IGFs in lung cancer risk is controversial. We assessed the role of tissue-derived IGFs in lung carcinogenesis. We found that IGF-I and IGF-II levels in bronchial tissue specimens containing high-grade dysplasia were significantly higher than in those containing normal epithelium, hyperplasia, and squamous metaplasia. Derivatives of human bronchial epithelial cell lines with activation mutation in KRAS(V12) or loss of p53 overexpressed IGF-I and IGF-II. The transformed characteristics of these cells were significantly suppressed by inactivation of IGF-IR or inhibition of IGF-I or IGF-II expression but enhanced by overexpression of IGF-IR or exposure to the tobacco carcinogens (TC) 4-(methylnitrosamino)-I-(3-pyridyl)-1-butanone and benzo(a)pyrene. We further determined the role of IGF-IR signaling in lung tumorigenesis by determining the antitumor activities of the selective IGF-IR tyrosine kinase inhibitor cis-3-[3-(4-methyl-piperazin-l-yl)-cyclobutyl]-1-(2-phenyl-quinolin-7-yl)-imidazo [1,5-a]pyrazin-8-ylamine using an in vitro progressive cell system and an in vivo mouse model with a lung-specific IGF-I transgene after exposure to TCs, including 4-(methylnitrosamino)-I-(3-pyridyl)-1-butanone plus benzo(a)pyrene. Our results show that airway epithelial cells produce IGFs in an autocrine or paracrine manner, and these IGFs act jointly with TCs to enhance lung carcinogenesis. Furthermore, the use of selective IGF-IR inhibitors may be a rational approach to controlling lung cancer.
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Affiliation(s)
- Woo-Young Kim
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Dance-Barnes ST, Kock ND, Moore JE, Lin EY, Mosley LJ, D'Agostino RB, McCoy TP, Townsend AJ, Miller MS. Lung tumor promotion by curcumin. Carcinogenesis 2009; 30:1016-23. [PMID: 19359593 DOI: 10.1093/carcin/bgp082] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Curcumin exhibits anti-inflammatory and antitumor activity and is being tested in clinical trials as a chemopreventive agent for colon cancer. Curcumin's chemopreventive activity was tested in a transgenic mouse model of lung cancer that expresses the human Ki-ras(G12C) allele in a doxycycline (DOX) inducible and lung-specific manner. The effects of curcumin were compared with the lung tumor promoter, butylated hydroxytoluene (BHT), and the lung cancer chemopreventive agent, sulindac. Treatment of DOX-induced mice with dietary curcumin increased tumor multiplicity (36.3 +/- 0.9 versus 24.3 +/- 0.2) and progression to later stage lesions, results which were similar to animals that were co-treated with DOX/BHT. Microscopic examination showed that the percentage of lung lesions that were adenomas and adenocarcinomas increased to 66% in DOX/BHT, 66% in DOX/curcumin and 49% in DOX/BHT/curcumin-treated groups relative to DOX only treated mice (19%). Immunohistochemical analysis also showed increased evidence of inflammation in DOX/BHT, DOX/curcumin and DOX/BHT/curcumin mice relative to DOX only treated mice. In contrast, co-treatment of DOX/BHT mice with 200 p.p.m. [DOSAGE ERROR CORRECTED] of sulindac inhibited the progression of lung lesions and reduced the inflammation. Lung tissue from DOX/curcumin-treated mice demonstrated a significant increase (33%; P = 0.01) in oxidative damage, as assessed by the levels of carbonyl protein formation, relative to DOX-treated control mice after 1 week on the curcumin diet. These results suggest that curcumin may exhibit organ-specific effects to enhance reactive oxygen species formation in the damaged lung epithelium of smokers and ex-smokers. Ongoing clinical trials thus may need to exclude smokers and ex-smokers in chemopreventive trials of curcumin.
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Affiliation(s)
- Stephanie T Dance-Barnes
- Department of Cancer Biology, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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Dance-Barnes ST, Kock ND, Floyd HS, Moore JE, Mosley LJ, D'Agostino RB, Pettenati MJ, Miller MS. Effects of mutant human Ki-ras(G12C) gene dosage on murine lung tumorigenesis and signaling to its downstream effectors. Toxicol Appl Pharmacol 2008; 231:77-84. [PMID: 18565564 DOI: 10.1016/j.taap.2008.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Revised: 04/08/2008] [Accepted: 04/18/2008] [Indexed: 11/16/2022]
Abstract
Studies in cell culture have suggested that the level of RAS expression can influence the transformation of cells and the signaling pathways stimulated by mutant RAS expression. However, the levels of RAS expression in vivo appear to be subject to feedback regulation, limiting the total amount of RAS protein that can be expressed. We utilized a bitransgenic mouse lung tumor model that expressed the human Ki-ras(G12C) allele in a tetracycline-inducible, lung-specific manner. Treatment for 12 months with 500 microg/ml of doxycycline (DOX) allowed for maximal expression of the human Ki-ras(G12C) allele in the lung, and resulted in the development of focal hyperplasia and adenomas. We determined if different levels of mutant RAS expression would influence the phenotype of the lung lesions. Treatment with 25, 100 and 500 microg/ml of DOX resulted in dose-dependent increases in transgene expression and tumor multiplicity. Microscopic analysis of the lungs of mice treated with the 25 microg/ml dose of DOX revealed infrequent foci of hyperplasia, whereas mice treated with the 100 and 500 microg/ml doses exhibited numerous hyperplastic foci and also adenomas. Immunohistochemical and RNA analysis of the downstream effector pathways demonstrated that different levels of mutant RAS transgene expression resulted in differences in the expression and/or phosphorylation of specific signaling molecules. Our results suggest that the molecular alterations driving tumorigenesis may differ at different levels of mutant Ki-ras(G12C) expression, and this should be taken into consideration when inducible transgene systems are utilized to promote tumorigenesis in mouse models.
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Affiliation(s)
- Stephanie T Dance-Barnes
- Department of Cancer Biology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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