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Frampton AE, Krell J, Giovannetti E, Jiao LR, Stebbing J. Role of miRNAs in the response to anticancer therapy. Pharmacogenomics 2012; 13:1663-6. [PMID: 23171328 DOI: 10.2217/pgs.12.34] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
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202
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MicroRNAs involved in regulating epithelial-mesenchymal transition and cancer stem cells as molecular targets for cancer therapeutics. Cancer Gene Ther 2012; 19:723-30. [PMID: 22975591 DOI: 10.1038/cgt.2012.58] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
One of the major challenges in cancer gene therapy is the identification of functionally relevant tumor-specific genes as the therapeutic targets. MicroRNAs (miRNAs) are a class of small, 22-25 nucleotides, endogenously expressed noncoding RNA. miRNAs are important genetic regulators: one miRNA can possibly target multiple genes and they can function as tumor promoters (oncogenic miRNAs, oncomirs) or tumor suppressors (anti-oncomirs). Therefore, the identification of misregulated miRNAs in cellular signaling pathways related to oncogenesis can have profound implications for cancer therapy. The epithelial-mesenchymal transition (EMT) converts epithelial cells into mesenchymal cells, a normal embryological process that frequently get activated during cancer invasion and metastasis. Recent evidence also supports the presence of a small subset of self-renewing, stem-like cells within the tumor mass that possess the capacity to seed new tumors and they have been termed 'cancer stem cells (CSC)'. Conceivably, these CSCs could provide a resource for cells that cause therapy resistance. Although the cell origin of CSCs remains to be fully elucidated, a growing body of evidence has demonstrated that the biology of EMT and CSCs is tightly linked with the sequences and compositions of miRNA molecules. Therefore, targeting miRNAs involved in EMT and CSCs regulation can provide novel miRNA-based therapeutic strategies in oncology.
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203
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Kacevska M, Ivanov M, Ingelman-Sundberg M. Epigenetic-dependent regulation of drug transport and metabolism: an update. Pharmacogenomics 2012; 13:1373-85. [DOI: 10.2217/pgs.12.119] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The pharmacokinetics of a drug are subject to large interindividual variability, which can result in lack of response or adverse drug reactions. In addition to genetic polymorphisms and drug interactions, key genes involved in the metabolism and transport of drugs are demonstrated to have epigenetic influences that can potentially affect interindividual variability in drug response. Emerging studies have focused on the importance of DNA methylation for ADME gene expression and for drug action and resistance, particularly in cancer. However, the epigenetic and ncRNA-dependent regulation of these genes, as well as the pharmacological consequences, is in need of greater attention. In the current review we provide an update of epigenetic and ncRNA-dependent regulation of ADME genes.
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Affiliation(s)
- Marina Kacevska
- Section of Pharmacogenetics, Department of Physiology & Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Maxim Ivanov
- Section of Pharmacogenetics, Department of Physiology & Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Magnus Ingelman-Sundberg
- Section of Pharmacogenetics, Department of Physiology & Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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204
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Liu L, Wang S, Chen R, Wu Y, Zhang B, Huang S, Zhang J, Xiao F, Wang M, Liang Y. Myc induced miR-144/451 contributes to the acquired imatinib resistance in chronic myelogenous leukemia cell K562. Biochem Biophys Res Commun 2012; 425:368-73. [DOI: 10.1016/j.bbrc.2012.07.098] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2012] [Accepted: 07/19/2012] [Indexed: 01/29/2023]
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205
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Lv K, Liu L, Wang L, Yu J, Liu X, Cheng Y, Dong M, Teng R, Wu L, Fu P, Deng W, Hu W, Teng L. Lin28 mediates paclitaxel resistance by modulating p21, Rb and Let-7a miRNA in breast cancer cells. PLoS One 2012; 7:e40008. [PMID: 22808086 PMCID: PMC3392258 DOI: 10.1371/journal.pone.0040008] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 05/30/2012] [Indexed: 12/15/2022] Open
Abstract
Resistance to chemotherapy is a major obstacle for the effective treatment of cancers. Lin28 has been shown to contribute to tumor relapse after chemotherapy; however, the relationship between Lin28 and chemoresistance remained unknown. In this study, we investigated the association of Lin28 with paclitaxel resistance and identified the underlying mechanisms of action of Lin28 in human breast cancer cell lines and tumor tissues. We found that the expression level of Lin28 was closely associated with the resistance to paclitaxel treatment. The T47D cancer cell line, which highly expresses Lin28, is more resistant to paclitaxel than the MCF7, Bcap-37 or SK-BR-3 cancer cell lines, which had low-level expression of Lin28. Knocking down of Lin28 in Lin28 high expression T47D cells increased the sensitivity to paclitaxel treatment, while stable expression of Lin28 in breast cancer cells effectively attenuated the sensitivity to paclitaxel treatment, resulting in a significant increase of IC50 values of paclitaxel. Transfection with Lin28 also significantly inhibited paclitaxel-induced apoptosis. We also found that Lin28 expression was dramatically increased in tumor tissues after neoadjuvant chemotherapy or in local relapse or metastatic breast cancer tissues. Moreover, further studies showed that p21, Rb and Let-7 miRNA were the molecular targets of Lin28. Overexpression of Lin28 in breast cancer cells considerably induced p21 and Rb expression and inhibited Let-7 miRNA levels. Our results indicate that Lin28 expression might be one mechanism underlying paclitaxel resistance in breast cancer, and Lin28 could be a potential target for overcoming paclitaxel resistance in breast cancer.
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Affiliation(s)
- Kezhen Lv
- Department of Gastrointestinal Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Liqun Liu
- Department of General Surgery, The First Affiliated Hospital-Huangpu Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Linbo Wang
- Key Laboratory of Biotherapy of Zhejiang Province, Department of Surgical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Jiren Yu
- Department of Gastrointestinal Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Xiaojiao Liu
- Department of Gastrointestinal Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yongxia Cheng
- Key Laboratory of Biotherapy of Zhejiang Province, Department of Surgical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Minjun Dong
- Key Laboratory of Biotherapy of Zhejiang Province, Department of Surgical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Rongyue Teng
- Key Laboratory of Biotherapy of Zhejiang Province, Department of Surgical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Linjiao Wu
- Department of Gastrointestinal Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Peifen Fu
- Department of Gastrointestinal Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Wuguo Deng
- Institute of Cancer Stem Cell, Dalian Medical University Cancer Center, Dalian, China
- State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China
- * E-mail: (WH); (LT); (WG)
| | - Wenxian Hu
- Key Laboratory of Biotherapy of Zhejiang Province, Department of Surgical Oncology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, China
- * E-mail: (WH); (LT); (WG)
| | - Lisong Teng
- Department of Gastrointestinal Surgery, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
- * E-mail: (WH); (LT); (WG)
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206
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Palma J, Yaddanapudi SC, Pigati L, Havens MA, Jeong S, Weiner GA, Weimer KME, Stern B, Hastings ML, Duelli DM. MicroRNAs are exported from malignant cells in customized particles. Nucleic Acids Res 2012; 40:9125-38. [PMID: 22772984 PMCID: PMC3467054 DOI: 10.1093/nar/gks656] [Citation(s) in RCA: 174] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
MicroRNAs (miRNAs) are released from cells in association with proteins or microvesicles. We previously reported that malignant transformation changes the assortment of released miRNAs by affecting whether a particular miRNA species is released or retained by the cell. How this selectivity occurs is unclear. Here we report that selectively exported miRNAs, whose release is increased in malignant cells, are packaged in structures that are different from those that carry neutrally released miRNAs (n-miRNAs), whose release is not affected by malignancy. By separating breast cancer cell microvesicles, we find that selectively released miRNAs associate with exosomes and nucleosomes. However, n-miRNAs of breast cancer cells associate with unconventional exosomes, which are larger than conventional exosomes and enriched in CD44, a protein relevant to breast cancer metastasis. Based on their large size, we call these vesicles L-exosomes. Contrary to the distribution of miRNAs among different microvesicles of breast cancer cells, normal cells release all measured miRNAs in a single type of vesicle. Our results suggest that malignant transformation alters the pathways through which specific miRNAs are exported from cells. These changes in the particles and their miRNA cargo could be used to detect the presence of malignant cells in the body.
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Affiliation(s)
- Jaime Palma
- Department of Cellular and Molecular Pharmacology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, USA
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207
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Liu C, Kelnar K, Vlassov AV, Brown D, Wang J, Tang DG. Distinct microRNA expression profiles in prostate cancer stem/progenitor cells and tumor-suppressive functions of let-7. Cancer Res 2012; 72:3393-404. [PMID: 22719071 PMCID: PMC3872033 DOI: 10.1158/0008-5472.can-11-3864] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
MiRNAs regulate cancer cells, but their potential effects on cancer stem/progenitor cells are still being explored. In this study, we used quantitative real-time-PCR to define miRNA expression patterns in various stem/progenitor cell populations in prostate cancer, including CD44+, CD133+, integrin α2β1+, and side population cells. We identified distinct and common patterns in these different tumorigenic cell subsets. Multiple tumor-suppressive miRNAs were downregulated coordinately in several prostate cancer stem/progenitor cell populations, namely, miR-34a, let-7b, miR-106a, and miR-141, whereas miR-301 and miR-452 were commonly overexpressed. The let-7 overexpression inhibited prostate cancer cell proliferation and clonal expansion in vitro and tumor regeneration in vivo. In addition, let-7 and miR-34a exerted differential inhibitory effects in prostate cancer cells, with miR-34a inducing G1 phase cell-cycle arrest accompanied by cell senescence and let-7 inducing G2-M phase cell-cycle arrest without senescence. Taken together, our findings define distinct miRNA expression patterns that coordinately regulate the tumorigenicity of prostate cancer cells.
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Affiliation(s)
- Can Liu
- Department of Molecular Carcinogenesis, The University of Texas M.D Anderson Cancer Center, Science Park, Smithville, TX 78957, USA
- Program in Molecular Carcinogenesis, The University of Texas Graduate School of Biomedical Sciences (GSBS) at Houston, The University of Texas M.D Anderson Cancer Center, Houston, TX 77030, USA
| | | | | | - David Brown
- Mirna Therapeutics, Inc., Austin, TX 78744, USA
| | - Junchen Wang
- Cancer Stem Cell Institute, Research Center for Translational Medicine, and Department of Pathology, East Hospital, Tongji University, Shanghai 200120, China
- Centers for Cancer Epigenetics, Stem Cell and Developmental Biology, RNA Interference and Non-coding RNAs, and Molecular Carcinogenesis, the University of Texas M.D Anderson Cancer Center, Houston, TX 77030, USA
| | - Dean G. Tang
- Department of Molecular Carcinogenesis, The University of Texas M.D Anderson Cancer Center, Science Park, Smithville, TX 78957, USA
- Program in Molecular Carcinogenesis, The University of Texas Graduate School of Biomedical Sciences (GSBS) at Houston, The University of Texas M.D Anderson Cancer Center, Houston, TX 77030, USA
- Cancer Stem Cell Institute, Research Center for Translational Medicine, and Department of Pathology, East Hospital, Tongji University, Shanghai 200120, China
- Centers for Cancer Epigenetics, Stem Cell and Developmental Biology, RNA Interference and Non-coding RNAs, and Molecular Carcinogenesis, the University of Texas M.D Anderson Cancer Center, Houston, TX 77030, USA
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208
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Du L, Pertsemlidis A. microRNA regulation of cell viability and drug sensitivity in lung cancer. Expert Opin Biol Ther 2012; 12:1221-39. [PMID: 22731874 DOI: 10.1517/14712598.2012.697149] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION microRNAs (miRNAs) are 19 - 23 nucleotide long RNAs found in multiple organisms that regulate gene expression and have been shown to play important roles in tumorigenesis. In the context of lung cancer, numerous studies have shown that tumor suppressor genes and oncogenes that play crucial roles in lung tumor development and progression are targets of miRNA regulation. Manipulation of miRNA levels that modulate lung cancer cell survival and drug sensitivity can therefore provide novel therapeutic targets and agents. AREAS COVERED Here, the authors review the published in vitro, in vivo and preclinical studies on the functional role of miRNAs in modulating lung cancer cell viability and drug response, and discuss the limitations and promise of translating current findings into miRNA-based therapeutic and diagnostic strategies. EXPERT OPINION Although many miRNAs have been identified as potent regulators of cell viability and drug sensitivity in lung cancer, most of them have not been characterized for potential clinical application. Further study is warranted to evaluate translation of the current findings to the clinic to improve the diagnosis and treatment of lung cancer. In addition, most studies have focused on non-small cell lung cancer (NSCLC). It is therefore important to raise interest in investigating miRNAs in small cell lung cancer (SCLC) as well as in comparative studies of miRNA expression and function in different histological subtypes of lung cancer.
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Affiliation(s)
- Liqin Du
- Greehey Children's Cancer Research Institute, Department of Cellular and Structural Biology, UT Health Science Center at San Antonio, San Antonio, TX 78229, USA
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209
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Guo H, Hu X, Ge S, Qian G, Zhang J. Regulation of RAP1B by miR-139 suppresses human colorectal carcinoma cell proliferation. Int J Biochem Cell Biol 2012; 44:1465-72. [PMID: 22642900 DOI: 10.1016/j.biocel.2012.05.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 05/15/2012] [Accepted: 05/21/2012] [Indexed: 12/21/2022]
Abstract
BACKGROUND MicroRNAs (miRNAs) are strongly implicated in carcinogenesis, but their specific roles in the major cancers have yet to be fully elucidated. METHODS The expression levels of miR-139 in colorectal carcinoma and paired normal tissues were examined using real-time PCR assays. Potential functions of miR-139 were evaluated in colorectal carcinoma cell lines (SW480, SW620, LS174 T, and HCT116) using miR-139 mimics, anti-miR-139, and siRNA RAP1B. RESULTS In this study, we determined that miR-139 is down-regulated in colorectal carcinoma (CRC) tissues. Lower miR-139 expression correlates with more advanced CRC and lower overall survival of patients with CRC. The ectopic expression of miR-139 in human CRC cells decreased cell growth and tumorigenicity, whereas the silencing of miR-139 promoted cell growth. Mechanistic studies revealed that miR-139 repressed the activity of a reporter gene fused to the 3'-untranslated region of RAP1B, whereas miR-139 silencing up-regulated the expression of the reporter gene. RNAi-mediated knockdown of RAP1B phenocopied the antiproliferative effect of miR-139, whereas the overexpression of RAP1B blocked miR-139-mediated antiproliferative effects in CRC cells. CONCLUSIONS Taken together, these results demonstrated that miR-139 decreases proliferation by directly targeting RAP1B, defining miR-139 as a new putative tumour suppressor miRNA in CRC.
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Affiliation(s)
- Haiyan Guo
- Department of Clinical Laboratory, No. 3 People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China.
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210
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Ashley N. Regulation of intestinal cancer stem cells. Cancer Lett 2012; 338:120-6. [PMID: 22546285 DOI: 10.1016/j.canlet.2012.04.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 04/19/2012] [Accepted: 04/22/2012] [Indexed: 02/07/2023]
Abstract
Colorectal tumours harbour a sub-population of cells with stem like properties termed 'cancer stem cells', which are believed to ultimately drive cancer growth. This review discusses recent advances in our understanding of both normal and cancer intestinal stem cells, with emphasis on similarities and differences. Specifically we discuss the role of the Wnt, Notch and BMP pathways and their roles in both stem cell proliferation and differentiation. Furthermore we discuss the emerging role of microRNA and the influence of environmental factors such as tumour associated myofibroblasts and hypoxia on cancer stem cell regulation.
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Affiliation(s)
- Neil Ashley
- Cancer and Immunogenetics Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, United Kingdom.
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211
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Cancer stem cells: in the line of fire. Cancer Treat Rev 2012; 38:589-98. [PMID: 22469558 DOI: 10.1016/j.ctrv.2012.03.003] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 03/07/2012] [Accepted: 03/09/2012] [Indexed: 12/20/2022]
Abstract
Most tumours appear to contain a sub-population(s) of self-renewing and expanding stem cells known as cancer stem cells (CSCs). The CSC model proposes that CSCs are at the apex of a hierarchically organized cell population, somewhat akin to normal tissue organization. Selection pressures may also facilitate the stochastic clonal expansion of sub-sets of cancer cells that may co-exist with CSCs and their progeny, moreover the trait of stemness may be more fluid than hitherto expected, and cells may switch between the stem and non-stem cell state. A large body of evidence points to the fact that CSCs are particularly resistant to radiotherapy and chemotherapy. In this review we discuss the basis of such resistance that highlights the roles of ABC transporters, aldehyde dehydrogenase (ALDH) activity, intracellular signalling pathways, the DNA damage response, hypoxia and proliferative quiescence as being significant determinants. In the light of such observations, we outline strategies for the successful eradication of CSCs, including targeting the self-renewal controlling pathways (Wnt, Notch and Hedgehog), ALDH activity and ABC transporters, blocking epithelial mesenchymal transition (EMT), differentiation therapy and niche targeting.
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212
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Abstract
There are considerable interindividual variations in drug absorption, distribution, metabolism and excretion (ADME) in humans, which may lead to undesired drug effects in pharmacotherapy. Some of the mechanistic causes are known, e.g., genetic polymorphism, inhibition and induction of ADME enzymes and transporters, while others such as posttranscriptional regulation of ADME genes are under active study. MicroRNAs (miRNAs) are a large group of small, noncoding RNAs that control posttranscriptional expression of target genes. More than 1000 miRNAs have been identified in the human genome, which may regulate thousands of protein-coding genes. Some miRNAs directly or indirectly control the expression of xenobiotic-metabolizing cytochrome P450 enzymes, ATP-binding cassette or solute carrier transporters and/or nuclear receptors. Consequently, intervention of miRNA epigenetic signaling may alter ADME gene expression, change the capacity of drug metabolism and transport, and influence the sensitivity of cells to xenobiotics. In addition, the expression of some ADME regulatory miRNAs is significantly changed in cells following the exposure to a given drug, and the consequent changes in ADME gene expression might result in distinct ADME properties and drug response. In this review, we summarized recent findings on the role of noncoding miRNAs in epigenetic regulation of ADME genes and discussed the potential impact on pharmacokinetics and pharmacodynamics.
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Affiliation(s)
- Ai-Ming Yu
- Department of Pharmaceutical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260-1200, USA
| | - Yu-Zhuo Pan
- Department of Pharmaceutical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260-1200, USA
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213
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Ju JA, Huang YC, Lan SH, Wang TH, Lin PC, Lee JC, Niu KC, Tian YF, Liu HS. Identification of colorectal cancer recurrence-related microRNAs. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.gmbhs.2012.04.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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214
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215
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Wang Y, Song GX, Li Q. Advances in understanding the relationship between microRNAs and colorectal cancer. Shijie Huaren Xiaohua Zazhi 2011; 19:3426-3431. [DOI: 10.11569/wcjd.v19.i33.3426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The development of colorectal cancer is a multi-factorial, multi-step process in which abnormal gene expression may play an important role. In recent years, it has been reported that microRNAs (miRNAs), which widely exist in eukaryotes, are closely related to gene expression regulation in colorectal cancer. These findings have greatly expanded our understanding of the pathogenesis of colorectal cancer and provide new ideas and methods for the diagnosis and treatment of this malignancy.
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