1
|
Rye MB, Krossa S, Hall M, van Mourik C, Bathen TF, Drabløs F, Tessem MB, Bertilsson H. The genes controlling normal function of citrate and spermine secretion are lost in aggressive prostate cancer and prostate model systems. iScience 2022; 25:104451. [PMID: 35707723 PMCID: PMC9189124 DOI: 10.1016/j.isci.2022.104451] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 04/12/2022] [Accepted: 05/17/2022] [Indexed: 11/22/2022] Open
Abstract
High secretion of the metabolites citrate and spermine is a unique hallmark for normal prostate epithelial cells, and is reduced in aggressive prostate cancer. However, the identity of the genes controlling this biological process is mostly unknown. In this study, we have created a gene signature of 150 genes connected to citrate and spermine secretion in the prostate. We have computationally integrated metabolic measurements with multiple transcriptomics datasets from the public domain, including 3826 tissue samples from prostate and prostate cancer. The accuracy of the signature is validated by its unique enrichment in prostate samples and prostate epithelial tissue compartments. The signature highlights genes AZGP1, ANPEP and metallothioneins with zinc-binding properties not previously studied in the prostate, and the expression of these genes are reduced in more aggressive cancer lesions. However, the absence of signature enrichment in common prostate model systems can make it challenging to study these genes mechanistically. Novel 150 gene signature reflecting prostatic citrate and spermine secretion Identified several zinc-binding proteins not previously investigated in the prostate The signature is absent in prostate model systems
Collapse
Affiliation(s)
- Morten Beck Rye
- Department of Clinical and Molecular Medicine, NTNU - Norwegian University of Science and Technology, P.O. Box 8905, 7491 Trondheim, Norway.,Clinic of Surgery, St.Olavs Hospital, Trondheim University Hospital, 7030 Trondheim, Norway.,Clinic of Laboratory Medicine, St.Olavs Hospital, Trondheim University Hospital, 7030 Trondheim, Norway.,BioCore - Bioinformatics Core Facility, NTNU - Norwegian University of Science and Technology, P.O. Box 8905, 7491 Trondheim, Norway
| | - Sebastian Krossa
- Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway
| | - Martina Hall
- Department of Biotechnology and Food Science, NTNU - Norwegian University of Science and Technology, Trondheim, Norway.,K. G. Jebsen Center for Genetic Epidemiology, NTNU - Norwegian University of Science and Technology, Trondheim, Norway
| | - Casper van Mourik
- Department of Clinical and Molecular Medicine, NTNU - Norwegian University of Science and Technology, P.O. Box 8905, 7491 Trondheim, Norway.,Institute for Life Science & Technology, Hanze University of Applied Sciences, 9747 AS Groningen, the Netherlands
| | - Tone F Bathen
- Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway
| | - Finn Drabløs
- Department of Clinical and Molecular Medicine, NTNU - Norwegian University of Science and Technology, P.O. Box 8905, 7491 Trondheim, Norway
| | - May-Britt Tessem
- Clinic of Surgery, St.Olavs Hospital, Trondheim University Hospital, 7030 Trondheim, Norway.,Department of Circulation and Medical Imaging, NTNU - Norwegian University of Science and Technology, Trondheim, Norway
| | - Helena Bertilsson
- Department of Clinical and Molecular Medicine, NTNU - Norwegian University of Science and Technology, P.O. Box 8905, 7491 Trondheim, Norway.,Clinic of Surgery, St.Olavs Hospital, Trondheim University Hospital, 7030 Trondheim, Norway
| |
Collapse
|
2
|
Differential Gene Expression Profiles between N-Terminal Domain and Ligand-Binding Domain Inhibitors of Androgen Receptor Reveal Ralaniten Induction of Metallothionein by a Mechanism Dependent on MTF1. Cancers (Basel) 2022; 14:cancers14020386. [PMID: 35053548 PMCID: PMC8773799 DOI: 10.3390/cancers14020386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/06/2022] [Accepted: 01/11/2022] [Indexed: 02/04/2023] Open
Abstract
Hormonal therapies for prostate cancer target the androgen receptor (AR) ligand-binding domain (LBD). Clinical development for inhibitors that bind to the N-terminal domain (NTD) of AR has yielded ralaniten and its analogues. Ralaniten acetate is well tolerated in patients at 3600 mgs/day. Clinical trials are ongoing with a second-generation analogue of ralaniten. Binding sites on different AR domains could result in differential effects on AR-regulated gene expression. Here, we provide the first comparison between AR-NTD inhibitors and AR-LBD inhibitors on androgen-regulated gene expression in prostate cancer cells using cDNA arrays, GSEA, and RT-PCR. LBD inhibitors and NTD inhibitors largely overlapped in the profile of androgen-induced genes that they each inhibited. However, androgen also represses gene expression by various mechanisms, many of which involve protein-protein interactions. De-repression of the transcriptome of androgen-repressed genes showed profound variance between these two classes of inhibitors. In addition, these studies revealed a unique and strong induction of expression of the metallothionein family of genes by ralaniten by a mechanism independent of AR and dependent on MTF1, thereby suggesting this may be an off-target. Due to the relatively high doses that may be encountered clinically with AR-NTD inhibitors, identification of off-targets may provide insight into potential adverse events, contraindications, or poor efficacy.
Collapse
|
3
|
Abstract
Metallothioneins (MTs) are small cysteine-rich proteins that play important roles in metal homeostasis and protection against heavy metal toxicity, DNA damage, and oxidative stress. In humans, MTs have four main isoforms (MT1, MT2, MT3, and MT4) that are encoded by genes located on chromosome 16q13. MT1 comprises eight known functional (sub)isoforms (MT1A, MT1B, MT1E, MT1F, MT1G, MT1H, MT1M, and MT1X). Emerging evidence shows that MTs play a pivotal role in tumor formation, progression, and drug resistance. However, the expression of MTs is not universal in all human tumors and may depend on the type and differentiation status of tumors, as well as other environmental stimuli or gene mutations. More importantly, the differential expression of particular MT isoforms can be utilized for tumor diagnosis and therapy. This review summarizes the recent knowledge on the functions and mechanisms of MTs in carcinogenesis and describes the differential expression and regulation of MT isoforms in various malignant tumors. The roles of MTs in tumor growth, differentiation, angiogenesis, metastasis, microenvironment remodeling, immune escape, and drug resistance are also discussed. Finally, this review highlights the potential of MTs as biomarkers for cancer diagnosis and prognosis and introduces some current applications of targeting MT isoforms in cancer therapy. The knowledge on the MTs may provide new insights for treating cancer and bring hope for the elimination of cancer.
Collapse
Affiliation(s)
- Manfei Si
- Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Dongcheng District, Beijing, 100730 China
| | - Jinghe Lang
- Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Dongcheng District, Beijing, 100730 China
| |
Collapse
|
4
|
Athanassiadou P, Bantis A, Gonidi M, Athanassiades P, Agelonidou E, Grapsa D, Nikolopoulou P, Patsouris E. The Expression of Metallothioneins on Imprint Smears of Prostate Carcinoma: Correlation with Clinicopathologic Parameters and Tumor Proliferative Capacity. TUMORI JOURNAL 2018; 93:189-94. [PMID: 17557567 DOI: 10.1177/030089160709300213] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aims and Background Metallothioneins are a family of metal- binding cysteine-rich proteins that play an important role in cellular processes such as proliferation and apoptosis, protection against oxidative stress and metal ion homeostasis and detoxification. Recent findings suggest that metallothioneins might play a significant role in the development and progression of prostate cancer. It has been also demonstrated that Ki-67 expression may have prognostic value for disease-free survival in cases of prostate carcinoma. Study Design Imprint smears samples obtained from 70 patients immediately after radical prostatectomy for prostatic carcinoma were immunostained with monoclonal antibodies against metallothioneins and Ki-67. Metallothionein expression was correlated with Ki-67 immunostaining, Gleason score, stage, preoperative prostate-specific antigen levels and biochemical recurrence. Results Metallothionein expression was shown to correlate strongly with Gleason score (P <0.001) and significantly with pathological staging and Ki-67 immunostaining (P <0.001, P <0.05, respectively). In contrast, no significant association between metallothioneins and preoperative PSA was demonstrated. Both of the studied markers (metallothioneins and Ki-67) correlated with recurrence (P = 0.009, P = 0.006, respectively). Conclusions The present findings support the independent predictive value of metallothioneins and Ki-67 in prostate cancer. However, additional data are needed in order to reveal the factors that influence the expression of metallothioneins in epithelial neoplastic cells and clarify their mechanism of action.
Collapse
Affiliation(s)
- Paulina Athanassiadou
- Pathology Laboratory-Cytology Unit, Medical School, Athens University, Athens, Greece.
| | | | | | | | | | | | | | | |
Collapse
|
5
|
Krizkova S, Kepinska M, Emri G, Eckschlager T, Stiborova M, Pokorna P, Heger Z, Adam V. An insight into the complex roles of metallothioneins in malignant diseases with emphasis on (sub)isoforms/isoforms and epigenetics phenomena. Pharmacol Ther 2017; 183:90-117. [PMID: 28987322 DOI: 10.1016/j.pharmthera.2017.10.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Metallothioneins (MTs) belong to a group of small cysteine-rich proteins that are ubiquitous throughout all kingdoms. The main function of MTs is scavenging of free radicals and detoxification and homeostating of heavy metals. In humans, 16 genes localized on chromosome 16 have been identified to encode four MT isoforms labelled by numbers (MT-1-MT-4). MT-2, MT-3 and MT-4 proteins are encoded by a single gene. MT-1 comprises many (sub)isoforms. The known active MT-1 genes are MT-1A, -1B, -1E, -1F, -1G, -1H, -1M and -1X. The rest of the MT-1 genes (MT-1C, -1D, -1I, -1J and -1L) are pseudogenes. The expression and localization of individual MT (sub)isoforms and pseudogenes vary at intra-cellular level and in individual tissues. Changes in MT expression are associated with the process of carcinogenesis of various types of human malignancies, or with a more aggressive phenotype and therapeutic resistance. Hence, MT (sub)isoform profiling status could be utilized for diagnostics and therapy of tumour diseases. This review aims on a comprehensive summary of methods for analysis of MTs at (sub)isoforms levels, their expression in single tumour diseases and strategies how this knowledge can be utilized in anticancer therapy.
Collapse
Affiliation(s)
- Sona Krizkova
- Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Marta Kepinska
- Department of Biomedical and Environmental Analysis, Faculty of Pharmacy, Wroclaw Medical University, Borowska 211, 50-556 Wroclaw, Poland
| | - Gabriella Emri
- Department of Dermatology, Faculty of Medicine, University of Debrecen, Nagyerdei krt 98, H-4032 Debrecen, Hungary
| | - Tomas Eckschlager
- Department of Paediatric Haematology and Oncology, 2nd Faculty of Medicine, Charles University, and University Hospital Motol, V Uvalu 84, CZ-150 06 Prague 5, Czech Republic
| | - Marie Stiborova
- Department of Biochemistry, Faculty of Science, Charles University, Albertov 2030, CZ-128 40 Prague 2, Czech Republic
| | - Petra Pokorna
- Department of Biochemistry, Faculty of Science, Charles University, Albertov 2030, CZ-128 40 Prague 2, Czech Republic; Department of Oncology, 2nd Faculty of Medicine, Charles University, and University Hospital Motol, V Uvalu 84, CZ-150 06 Prague 5, Czech Republic
| | - Zbynek Heger
- Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Vojtech Adam
- Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno, Czech Republic; Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic.
| |
Collapse
|
6
|
Shin CH, Lee MG, Han J, Jeong SI, Ryu BK, Chi SG. Identification of XAF1-MT2A mutual antagonism as a molecular switch in cell-fate decisions under stressful conditions. Proc Natl Acad Sci U S A 2017; 114:5683-5688. [PMID: 28507149 PMCID: PMC5465913 DOI: 10.1073/pnas.1700861114] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
XIAP-associated factor 1 (XAF1) is a tumor suppressor that is commonly inactivated in multiple human neoplasms. However, the molecular mechanism underlying its proapoptotic function remains largely undefined. Here, we report that XAF1 induction by heavy metals triggers an apoptotic switch of stress response by destabilizing metallothionein 2A (MT2A). XAF1 directly interacts with MT2A and facilitates its lysosomal degradation, resulting in the elevation of the free intercellular zinc level and subsequent activation of p53 and inactivation of XIAP. Intriguingly, XAF1 is activated as a unique transcription target of metal-regulatory transcription factor-1 (MTF-1) in signaling apoptosis, and its protein is destabilized via the lysosomal pathway by MTF-1-induced MT2A under cytostatic stress conditions, indicating the presence of mutual antagonism between XAF1 and MT2A. The antagonistic interplay between XAF1 and MT2A acts as a key molecular switch in MTF-1-mediated cell-fate decisions and also plays an important role in cell response to various apoptotic and survival factors. Wild-type (WT) XAF1 but not MT2A binding-deficient mutant XAF1 increases the free intracellular zinc level and accelerates WT folding of p53 and degradation of XIAP. Consistently, XAF1 evokes a more drastic apoptotic effect in p53+/+ versus isogenic p53-/- cells. Clinically, expression levels of XAF1 and MT2A are inversely correlated in primary colon tumors and multiple cancer cell lines. XAF1-depleted xenograft tumors display an increased growth rate and a decreased apoptotic response to cytotoxic heavy metals with strong MT2A expression. Collectively, this study uncovers an important role for XAF1-MT2A antagonism as a linchpin to govern cell fate under various stressful conditions including heavy metal exposure.
Collapse
Affiliation(s)
- Cheol-Hee Shin
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| | - Min-Goo Lee
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| | - Jikhyon Han
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| | - Seong-In Jeong
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| | - Byung-Kyu Ryu
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| | - Sung-Gil Chi
- Department of Life Sciences, Korea University, Seoul 02841, Korea
| |
Collapse
|
7
|
Dziegiel P, Pula B, Kobierzycki C, Stasiolek M, Podhorska-Okolow M. The Role of Metallothioneins in Carcinogenesis. ADVANCES IN ANATOMY EMBRYOLOGY AND CELL BIOLOGY 2016. [DOI: 10.1007/978-3-319-27472-0_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
8
|
Gui T, Dong X, Li R, Li Y, Wang Z. Identification of hepatocellular carcinoma-related genes with a machine learning and network analysis. J Comput Biol 2015; 22:63-71. [PMID: 25247452 DOI: 10.1089/cmb.2014.0122] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Liver cancer is one of the leading causes of cancer mortality worldwide. Hepatocellular carcinoma (HCC) is the main type of liver cancer. We applied a machine learning approach with maximum-relevance-minimum-redundancy (mRMR) algorithm followed by incremental feature selection (IFS) to a set of microarray data generated from 43 tumor and 52 nontumor samples. With the machine learning approach, we identified 117 gene probes that could optimally separate tumor and nontumor samples. These genes not only include known HCC-relevant genes such as MT1X, BMI1, and CAP2, but also include cancer genes that were not found previously to be closely related to HCC, such as TACSTD2. Then, we constructed a molecular interaction network based on the protein-protein interaction (PPI) data from the STRING database and identified 187 genes on the shortest paths among the genes identified with the machine learning approach. Network analysis reveals new potential roles of ubiquitin C in the pathogenesis of HCC. Based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, we showed that the identified subnetwork is significantly enriched in biological processes related to cell death. These results bring new insights of understanding the process of HCC.
Collapse
Affiliation(s)
- Tuantuan Gui
- 1 Key Laboratory of Systems Biology, Shanghai Institutes for Biological Sciences , Chinese Academy of Sciences, Shanghai, P.R. China
| | | | | | | | | |
Collapse
|
9
|
Ma D, Zhou Z, Yang B, He Q, Zhang Q, Zhang XH. Association of molecular biomarkers expression with biochemical recurrence in prostate cancer through tissue microarray immunostaining. Oncol Lett 2015; 10:2185-2191. [PMID: 26622816 PMCID: PMC4579815 DOI: 10.3892/ol.2015.3556] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Accepted: 06/16/2015] [Indexed: 01/24/2023] Open
Abstract
The aim of the present study was to investigate the prognostic role of metallothionein-2A (MT-2A), E-cadherin, interleukin-6 (IL-6), cyclin-E, proliferating cell nuclear antigen (PCNA) and B cell lymphoma (Bcl)-2 in the biochemical recurrence of prostate cancer (PCa) using tissue microarray immunostaining. Tissue specimens from 128 PCa patients who underwent radical prostatectomy were processed and transferred onto tissue microarrays. The clinicopathological parameters of PCa patients were also recorded. Following immunohistochemical examination of MT-2A, E-cadherin, IL-6, cyclin-E, PCNA and Bcl-2 expression in PCa specimens, association analysis of biomarkers expression with the biochemical recurrence of PCa was performed. The results revealed that the overall rate of biochemical recurrence was 30.5% (39/128) and the median biochemical recurrence-free time was 19 months (range, 6–35 months). The biochemical recurrence rates in low-, intermediate- and high-risk PCa classification were 14.8 (8/54), 38.7 (24/62) and 58.3% (7/12), respectively. Survival analysis demonstrated that a decreased biochemical recurrence-free survival rate was noted in PCa cases with positive MT-2A and cyclin E expression as well as those with negative E-cadherin expression (P=0.022, 0.028 and 0.011, respectively). Subsequent multivariate Cox analysis revealed that MT-2A [hazard ratio (HR)=2.01; 95% confidence interval (CI)=1.08–3.15; P=0.005], E-cadherin (HR=1.79; 95% CI=1.08–2.21; P=0.042) and cyclin E (HR=1.92; 95% CI=1.22–2.45; P=0.020) were independent predictors of the biochemical recurrence of PCa. In conclusion, the present study provided clinical evidence that evaluation of molecular biomarkers expression may improve clinical prognostic accuracy for the biochemical recurrence of PCa. Of note, the expression of MT-2A, cyclin E and E-cadherin may serve as independent predictors for biochemical recurrence of PCa.
Collapse
Affiliation(s)
- Ding Ma
- Department of Urology, Peking University Shougang Hospital, Beijing 100144, P.R. China
| | - Zhe Zhou
- Department of Urology, Peking University Shougang Hospital, Beijing 100144, P.R. China
| | - Bing Yang
- Department of Urology, Peking University Shougang Hospital, Beijing 100144, P.R. China
| | - Qun He
- Department of Urology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Qian Zhang
- Department of Urology, Peking University First Hospital, Beijing 100034, P.R. China
| | - Xiang-Hua Zhang
- Department of Urology, Peking University Shougang Hospital, Beijing 100144, P.R. China
| |
Collapse
|
10
|
Brazão-Silva MT, Rodrigues MFS, Eisenberg ALA, Dias FL, de Castro LM, Nunes FD, Faria PR, Cardoso SV, Loyola AM, de Sousa SCOM. Metallothionein gene expression is altered in oral cancer and may predict metastasis and patient outcomes. Histopathology 2015; 67:358-67. [PMID: 25640883 DOI: 10.1111/his.12660] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 01/23/2015] [Indexed: 01/02/2023]
Abstract
AIMS Metallothioneins (MTs) are proteins associated with the carcinogenesis and prognosis of various tumours. Previous studies have shown their potential as biomarkers in oral squamous cell carcinoma (OSCC). Aiming to understand more clearly the function of MTs in OSCC we evaluated, for the first time, the gene expression profile of MTs in this neoplasm. MATERIALS AND RESULTS Tissue samples from 35 cases of tongue and/or floor of mouth OSCC, paired with their corresponding non-neoplastic oral mucosa (NNOM), were retrieved (2007-09). All tissues were analysed for the following genes using TaqMan(®) reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays: MT1A, MT1B, MT1E, MT1F, MT1G, MT1H, MT1X, MT2A, MT3 and MT4. The expression of MT1B and MT1H was seldom detected in both OSCC and NNOM. A significant loss of MT1A, MT1X, MT3 and MT4 expression and gain of MT1F expression was observed in OSCC, compared to NNOM. Cases with MT1G down-regulation exhibited the worst prognoses. The up-regulation of MT1X was restricted to non-metastatic cases, whereas up-regulation of MT3 was related to cases with lymph node metastasis. CONCLUSIONS Metallothionein mRNA expression is altered significantly in oral squamous cell carcinomas. The expression of MT1G, MT1X and MT3 may aid in the prognostic discrimination of OSCC cases.
Collapse
Affiliation(s)
- Marco T Brazão-Silva
- PhD program in Estomatology and Basic and Applied Pathology, School of Dentistry, University of São Paulo, São Paulo, Brazil
| | | | - Ana Lúcia A Eisenberg
- Department of Pathology, Brazilian National Cancer Institute/INCA, Rio de Janeiro, Brazil
| | - Fernando L Dias
- Department of Head and Neck Surgery, Brazilian National Cancer Institute/INCA, Rio de Janeiro, Brazil
| | - Luciana M de Castro
- National Tumor Bank, Brazilian National Cancer Institute/INCA, Rio de Janeiro, Brazil
| | - Fábio D Nunes
- PhD program in Estomatology and Basic and Applied Pathology, School of Dentistry, University of São Paulo, São Paulo, Brazil.,Laboratory of Molecular Pathology, School of Dentistry, University of São Paulo, São Paulo, Brazil.,Department of Oral Pathology, School of Dentistry, University of São Paulo, São Paulo, Brazil
| | - Paulo R Faria
- Department of Histology and Morphology, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Brazil
| | - Sérgio V Cardoso
- Department of Oral Pathology, School of Dentistry, Federal University of Uberlândia, Uberlândia, Brazil
| | - Adriano M Loyola
- Department of Oral Pathology, School of Dentistry, Federal University of Uberlândia, Uberlândia, Brazil
| | - Suzana C O M de Sousa
- PhD program in Estomatology and Basic and Applied Pathology, School of Dentistry, University of São Paulo, São Paulo, Brazil.,Department of Oral Pathology, School of Dentistry, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
11
|
Using transcriptomics to guide lead optimization in drug discovery projects: Lessons learned from the QSTAR project. Drug Discov Today 2015; 20:505-13. [PMID: 25582842 DOI: 10.1016/j.drudis.2014.12.014] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/02/2014] [Accepted: 12/22/2014] [Indexed: 12/14/2022]
Abstract
The pharmaceutical industry is faced with steadily declining R&D efficiency which results in fewer drugs reaching the market despite increased investment. A major cause for this low efficiency is the failure of drug candidates in late-stage development owing to safety issues or previously undiscovered side-effects. We analyzed to what extent gene expression data can help to de-risk drug development in early phases by detecting the biological effects of compounds across disease areas, targets and scaffolds. For eight drug discovery projects within a global pharmaceutical company, gene expression data were informative and able to support go/no-go decisions. Our studies show that gene expression profiling can detect adverse effects of compounds, and is a valuable tool in early-stage drug discovery decision making.
Collapse
|
12
|
Werynska B, Pula B, Muszczynska-Bernhard B, Gomulkiewicz A, Piotrowska A, Prus R, Podhorska-Okolow M, Jankowska R, Dziegiel P. Metallothionein 1F and 2A overexpression predicts poor outcome of non-small cell lung cancer patients. Exp Mol Pathol 2012; 94:301-8. [PMID: 23064051 DOI: 10.1016/j.yexmp.2012.10.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2012] [Revised: 10/02/2012] [Accepted: 10/03/2012] [Indexed: 11/26/2022]
Abstract
Metallothioneins (MT) are intracellular, low molecular weight proteins (6-7 kDa) involved in binding of metal ions, scavenging of free radicals, cell proliferation and apoptosis and resistance to certain chemotherapeutics. Four basic families of MT proteins are distinguished: MT-I, MT-II, MT-III, MT-IV, within each of them different isoforms occur. The study aimed at examining the expression level of nine MT isoforms: MT-1A, -1B, -1E, -1F, -1G, -1H, -1X, MT-2A and MT-IV by using real-time PCR and MT-I/II expression by immunohistochemical (IHC) technique in 69 cases of non-small cell lung cancer (NSCLC) and 12 non-malignant lung tissues (NMLT) and to correlate them with patients clinicopathological data and Ki-67 antigen expression. Out of all the analyzed cases, 62 (89.9%) demonstrated an increased MT-I/II expression. MT-1B, 1F, -1G, -1H and MT-1X were significantly up-regulated, whereas MT-1E was significantly down-regulated in NSCLC as compared to NMLT. Only in two cases MT-IV mRNA expression was noted. Significant positive correlations were observed between each particular MT isoform expressions. Higher MT-1F and MT-1A mRNA expression was associated with larger primary tumor size (P=0.0362 and P<0.0001, respectively). Moreover, up-regulated MT-1F mRNA expression was associated with higher grade of malignancy of NSCLC (P=0.0085). Higher MT-1B mRNA expression was associated with squamocellular and adenocarcinoma subtype of NSCLC (P=0.0358). Univariate analysis showed, that up-regulated MT-1F and MT-2A mRNA predicted poor patients' survival (P=0.0206 and P=0.0097, respectively). The levels of MT-1F and MT-2A mRNA could be considered as new markers of poor prognosis of NSCLC patients.
Collapse
Affiliation(s)
- Bozena Werynska
- Department of Pulmonology and Pulmonary Tumours, Medical University in Wroclaw, Poland
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Arriaga JM, Levy EM, Bravo AI, Bayo SM, Amat M, Aris M, Hannois A, Bruno L, Roberti MP, Loria FS, Pairola A, Huertas E, Mordoh J, Bianchini M. Metallothionein expression in colorectal cancer: relevance of different isoforms for tumor progression and patient survival. Hum Pathol 2011; 43:197-208. [PMID: 21820154 DOI: 10.1016/j.humpath.2011.04.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 04/15/2011] [Accepted: 04/22/2011] [Indexed: 11/27/2022]
Abstract
Metallothioneins are a family of small, cysteine-rich proteins with many functions. Immunohistochemical evaluation of all metallothionein 1 + 2 isoforms in colorectal tumors has demonstrated an important down-regulation compared with normal tissue, although its prognostic significance is unclear. Moreover, the contribution of individual isoforms to overall metallothionein down-regulation is not known. To address these important issues, we analyzed the messenger RNA expression levels of all functional metallothionein 1 + 2 isoforms by quantitative reverse transcription polymerase chain reaction in 22 pairs of normal and tumor-microdissected epithelia and correlated these to the overall immunohistochemical protein expression. Our results showed that 5 isoforms (MT1G, 1E, 1F, 1H, and 1M) were lost during the transition from normal mucosa to tumor, whereas MT1X and MT2A were less down-regulated, and their expression was correlated with overall protein positivity. Second, we showed that MT1G hypermethylation occurred in cell lines and in 29% of tumor samples, whereas histone deacetylase inhibitors are able to induce most isoforms. Furthermore, we analyzed by immunohistochemistry 107 normal mucosae, 25 adenomas, 81 carcinomas, and 19 lymph node metastases to evaluate metallothionein expression during different stages of cancer development and to assess its relationship to patient survival. A lower immunohistochemical expression was associated with poorer survival, although it was not an independent predictor. Overall, this study identifies for the first time the relevant metallothionein isoforms for colorectal cancer progression, supports the concept that their loss is associated with worse prognosis, and suggests 2 mechanisms for epigenetic repression of metallothionein expression in colorectal tumors.
Collapse
Affiliation(s)
- Juan Martín Arriaga
- Centro de Investigaciones Oncológicas de la Fundación Cáncer, 1426 Buenos Aires, Argentina
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Byeon JS, Jeong JY, Kim MJ, Lee SM, Nam WH, Myung SJ, Kim JG, Yang SK, Kim JH, Suh DJ. Adiponectin and adiponectin receptor in relation to colorectal cancer progression. Int J Cancer 2011; 127:2758-67. [PMID: 21351255 DOI: 10.1002/ijc.25301] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Although obesity is a risk factor for colorectal cancer, the underlying mechanism is not clear. Adiponectin is an adipokine that binds to 2 types of receptors, AdipoR1 and AdipoR2. The plasma concentrations of adiponectin are reduced in obese individuals and adiponectin has been reported to have anticarcinogenic properties. Furthermore, AdipoR1 and AdipoR2 have been reported to be expressed in several malignancies. However, little is known about the expression of AdipoR1 and AdipoR2 in colorectal cancer and its clinicopathological implications. In addition, the relationship between adiponectin and colorectal cancer has not yet been determined. Here, we sought to investigate adiponectin and adiponectin receptors in relation to colorectal cancer. AdipoR1 and AdipoR2 immunostaining was detected in 72 and 68% of human colorectal cancer tissue, respectively. AdipoR1 and AdipoR2 expression levels were inversely related to T stage. The lowest AdipoR1 and AdipoR2 expression were detected in poorly differentiated adenocarcinoma. RT-PCR also showed the expression of AdipoR1 and AdipoR2 in HCT116 and SW620. MTT assay and TUNEL assay demonstrated the tendency of growth inhibition and apoptosis induction in both cell lines after full-length adiponectin treatment although statistically insignificant. Microarray analysis revealed several gene responses to full-length adiponectin, including upregulation of ENDOGL1 and MT1G. In conclusion, AdipoR1 and AdipoR2 may be intimately related to the progression of colorectal cancer. Further studies may be warranted to assess adiponectin and its receptors as a novel target for inhibition of colorectal cancer growth.
Collapse
Affiliation(s)
- Jeong-Sik Byeon
- Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Lee JD, Wu SM, Lu LY, Yang YT, Jeng SY. Cadmium concentration and metallothionein expression in prostate cancer and benign prostatic hyperplasia of humans. J Formos Med Assoc 2009; 108:554-9. [PMID: 19586829 DOI: 10.1016/s0929-6646(09)60373-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
BACKGROUND/PURPOSE Cadmium (Cd) causes various genitourinary disorders and is a carcinogen for prostate cancer. Metallothionein (MT) is a protein that detoxifies heavy metals. We evaluated changes in Cd concentration and MT expression in human prostate cancer (CaP) and benign prostatic hyperplasia (BPH). Our goal was to clarify the relationship between Cd concentration and MT expression in prostatic diseases. METHODS The experimental group consisted of 18 patients who underwent radical prostatectomy for CaP. The control group consisted of 35 patients who underwent transurethral resection of the prostate for BPH. Tissue samples were acquired from the gross tumor site and from resected chips. We determined Cd concentration by atomic absorption, MT expression by immunoblotting, and immunohistochemical staining. The significance of between-group differences for these outcomes was analyzed using Student's t tests. RESULTS There was no statistically significant difference in Cd concentration between the CaP and BPH groups. Immunoblots from both groups revealed a single band. The relative intensity of the MT band was 0.58 +/- 0.09 in the BPH group and 0.17 +/- 0.03 in the CaP group. MT expression in patients with BPH was 3.4-fold higher than in those with CaP. CONCLUSION MT may bind heavy metals and protect patients from CaP. Additional studies are needed to reveal the factors that influence the expression of MT in prostate epithelial cells, and to analyze the free and compound forms of Cd at the same time.
Collapse
Affiliation(s)
- Jane-Dar Lee
- Division of Urology, Department of Surgery, Taichung Armed Forces General Hospital, Taiwan
| | | | | | | | | |
Collapse
|
16
|
Ma S, Huang J, Moran MS. Identification of genes associated with multiple cancers via integrative analysis. BMC Genomics 2009; 10:535. [PMID: 19919702 PMCID: PMC2785840 DOI: 10.1186/1471-2164-10-535] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Accepted: 11/17/2009] [Indexed: 12/03/2022] Open
Abstract
Background Advancement in gene profiling techniques makes it possible to measure expressions of thousands of genes and identify genes associated with development and progression of cancer. The identified cancer-associated genes can be used for diagnosis, prognosis prediction, and treatment selection. Most existing cancer microarray studies have been focusing on the identification of genes associated with a specific type of cancer. Recent biomedical studies suggest that different cancers may share common susceptibility genes. A comprehensive description of the associations between genes and cancers requires identification of not only multiple genes associated with a specific type of cancer but also genes associated with multiple cancers. Results In this article, we propose the Mc.TGD (Multi-cancer Threshold Gradient Descent), an integrative analysis approach capable of analyzing multiple microarray studies on different cancers. The Mc.TGD is the first regularized approach to conduct "two-dimensional" selection of genes with joint effects on cancer development. Simulation studies show that the Mc.TGD can more accurately identify genes associated with multiple cancers than meta analysis based on "one-dimensional" methods. As a byproduct, identification accuracy of genes associated with only one type of cancer may also be improved. We use the Mc.TGD to analyze seven microarray studies investigating development of seven different types of cancers. We identify one gene associated with six types of cancers and four genes associated with five types of cancers. In addition, we also identify 11, 9, 18, and 17 genes associated with 4 to 1 types of cancers, respectively. We evaluate prediction performance using a Leave-One-Out cross validation approach and find that only 4 (out of 570) subjects cannot be properly predicted. Conclusion The Mc.TGD can identify a short list of genes associated with one or multiple types of cancers. The identified genes are considerably different from those identified using meta analysis or analysis of marginal effects.
Collapse
Affiliation(s)
- Shuangge Ma
- School of Public Health, Yale University, New Haven, CT 06520, USA.
| | | | | |
Collapse
|
17
|
Lin SF, Wei H, Maeder D, Franklin RB, Feng P. Profiling of zinc-altered gene expression in human prostate normal vs. cancer cells: a time course study. J Nutr Biochem 2008; 20:1000-12. [PMID: 19071009 DOI: 10.1016/j.jnutbio.2008.09.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Revised: 09/03/2008] [Accepted: 09/09/2008] [Indexed: 12/31/2022]
Abstract
We have demonstrated that zinc exposure induces apoptosis in human prostate cancer cells (PC-3) and benign hyperplasia cells (BPH), but not in normal prostate cells (HPR-1). However, the mechanisms underlying the effects of zinc on prostate cancer cell growth and zinc homeostasis remain unclear. To explore the zinc effect on gene expression profiles in normal (HPR-1) and malignant prostate cells (PC-3), we conducted a time course study of Zn treatment with microarray analysis. Microarray data were evaluated and profiled using computational approach for the primary and secondary data analyses. Final analyses were focused on the genes (1) highly sensitive to zinc; (2) associated with zinc homeostasis, i.e., metallothioneins (MTs), solute zinc carriers (ZIPs) and zinc exporters (ZnTs); (3) relevant to several oncogenic pathways. Zinc-mediated mRNA levels of MT isotypes were further validated by semi-quantitative RT-PCR. Results showed that zinc effect on genome-wide expression patterns was cell-type specific, and zinc appeared to have mainly down-regulatory effects on thousands of genes (1953 in HPR-1; 3534 in PC-3) with a threshold of +/-2.5-fold, while fewer genes were up-regulated (872 in HPR-1; 571 in PC-3). The patterns of zinc effect on functional MT genes' expression provided evidence for the cell type-dependent zinc accumulation and zinc-induced apoptosis in prostate cells. In PC-3 cells, zinc significantly up-regulated the expression of MT-1 isotypes MT-1J and MT-1M, denoted previously as "nonfunctional" MT genes, and now a depictive molecular structure of MT-1J was proposed. Examination of genes involved in oncogenic pathways indicated that certain genes, e.g., Fos, Akt1, Jak3 and PI3K, were highly regulated by zinc with cell-type specificity. This work provided an extensive database on zinc-related prostate cancer research. The strategy of data analysis was devoted to finding genes highly sensitive to Zn, and the genes associated with zinc accumulation and zinc-induced apoptosis. The results indicate that zinc regulation of gene expression is cell-type specific, and MT genes play important roles in prostate malignancy.
Collapse
Affiliation(s)
- Shu-Fei Lin
- Department of Oncology and Diagnostic Sciences, Dental School, University of Maryland at Baltimore, Baltimore, MD 21201, USA.
| | | | | | | | | |
Collapse
|
18
|
Pedersen MØ, Larsen A, Stoltenberg M, Penkowa M. The role of metallothionein in oncogenesis and cancer prognosis. ACTA ACUST UNITED AC 2008; 44:29-64. [PMID: 19348910 DOI: 10.1016/j.proghi.2008.10.001] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Accepted: 10/02/2008] [Indexed: 12/12/2022]
Abstract
The antiapoptotic, antioxidant, proliferative, and angiogenic effects of metallothionein (MT)-I+II has resulted in increased focus on their role in oncogenesis, tumor progression, therapy response, and patient prognosis. Studies have reported increased expression of MT-I+II mRNA and protein in various human cancers; such as breast, kidney, lung, nasopharynx, ovary, prostate, salivary gland, testes, urinary bladder, cervical, endometrial, skin carcinoma, melanoma, acute lymphoblastic leukemia (ALL), and pancreatic cancers, where MT-I+II expression is sometimes correlated to higher tumor grade/stage, chemotherapy/radiation resistance, and poor prognosis. However, MT-I+II are downregulated in other types of tumors (e.g. hepatocellular, gastric, colorectal, central nervous system (CNS), and thyroid cancers) where MT-I+II is either inversely correlated or unrelated to mortality. Large discrepancies exist between different tumor types, and no distinct and reliable association exists between MT-I+II expression in tumor tissues and prognosis and therapy resistance. Furthermore, a parallel has been drawn between MT-I+II expression as a potential marker for prognosis, and MT-I+II's role as oncogenic factors, without any direct evidence supporting such a parallel. This review aims at discussing the role of MT-I+II both as a prognostic marker for survival and therapy response, as well as for the hypothesized role of MT-I+II as causal oncogenes.
Collapse
Affiliation(s)
- Mie Ø Pedersen
- Section of Neuroprotection, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, The Panum Institute, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark.
| | | | | | | |
Collapse
|
19
|
Prueitt RL, Yi M, Hudson RS, Wallace TA, Howe TM, Yfantis HG, Lee DH, Stephens RM, Liu CG, Calin GA, Croce CM, Ambs S. Expression of microRNAs and protein-coding genes associated with perineural invasion in prostate cancer. Prostate 2008; 68:1152-64. [PMID: 18459106 PMCID: PMC2597330 DOI: 10.1002/pros.20786] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Perineural invasion (PNI) is the dominant pathway for local invasion in prostate cancer. To date, only few studies have investigated the molecular differences between prostate tumors with PNI and those without it. METHODS To evaluate the involvement of both microRNAs and protein-coding genes in PNI, we determined their genome-wide expression with a custom microRNA microarray and Affymetrix GeneChips in 50 prostate adenocarcinomas with PNI and 7 without it. In situ hybridization (ISH) and immunohistochemistry was used to validate candidate genes. RESULTS Unsupervised classification of the 57 adenocarcinomas revealed two clusters of tumors with distinct global microRNA expression. One cluster contained all non-PNI tumors and a subgroup of PNI tumors. Significance analysis of microarray data yielded a list of microRNAs associated with PNI. At a false discovery rate (FDR)<10%, 19 microRNAs were higher expressed in PNI tumors than in non-PNI tumors. The most differently expressed microRNA was miR-224. ISH showed that this microRNA is expressed by perineural cancer cells. The analysis of protein-coding genes identified 34 transcripts that were differently expressed by PNI status (FDR<10%). These transcripts were down-regulated in PNI tumors. Many of those encoded metallothioneins and proteins with mitochondrial localization and involvement in cell metabolism. Consistent with the microarray data, perineural cancer cells tended to have lower metallothionein expression by immunohistochemistry than nonperineural cancer cells. CONCLUSIONS Although preliminary, our findings suggest that alterations in microRNA expression, mitochondrial function, and cell metabolism occur at the transition from a noninvasive prostate tumor to a tumor with PNI.
Collapse
Affiliation(s)
- Robyn L. Prueitt
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD
| | - Ming Yi
- Advanced Biomedical Computing Center, NCI-Frederick/SAIC-Frederick Inc., Frederick, MD
| | - Robert S. Hudson
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD
| | - Tiffany A. Wallace
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD
| | - Tiffany M. Howe
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD
| | - Harris G. Yfantis
- Pathology and Laboratory Medicine, Baltimore Veterans Affairs Medical Center, Baltimore, MD, USA
| | - Dong. H. Lee
- Pathology and Laboratory Medicine, Baltimore Veterans Affairs Medical Center, Baltimore, MD, USA
| | - Robert M. Stephens
- Advanced Biomedical Computing Center, NCI-Frederick/SAIC-Frederick Inc., Frederick, MD
| | - Chang-Gong Liu
- Department of Molecular Virology, Immunology, and Medical Genetics and Cancer Comprehensive Center, Ohio State University, Columbus, OH
| | - George A. Calin
- Experimental Therapeutics Department, MD Anderson Cancer Center, Houston, TX, USA
| | - Carlo M. Croce
- Department of Molecular Virology, Immunology, and Medical Genetics and Cancer Comprehensive Center, Ohio State University, Columbus, OH
| | - Stefan Ambs
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD
| |
Collapse
|
20
|
Albrecht AL, Singh RK, Somji S, Sens MA, Sens DA, Garrett SH. Basal and metal-induced expression of metallothionein isoform 1 and 2 genes in the RWPE-1 human prostate epithelial cell line. J Appl Toxicol 2008; 28:283-93. [PMID: 17590860 DOI: 10.1002/jat.1277] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The human prostate gland has low basal expression of the metallothionein-1 and -2 proteins. In prostate cancer, MT-1/2 protein expression is variable and correlates directly with the increasing Gleason score of the tumor. The goal of the present study was to determine if the RWPE-1 cell line is a good model to elucidate the mechanisms underlying the alterations in MT-1/2 expression that occur during the development of prostate cancer. It was shown that the RWPE-1 cell line and in situ prostate tissue have identical expression profiles of MT-1 and MT-2 isoform-specific mRNAs (MT-1E, MT-1X and MT-2A) and similar levels of MT-1/2 protein. It was also shown that the RWPE-1 cells respond to Zn(+2) and Cd(+2) exposure by induction of the basally expressed MT mRNAs and the accumulation of high levels MT-1/2 protein (in excess of 10% of total protein). It was also shown that additional MT-1 mRNAs were expressed when the cells were exposed to either metal; MT-1A, MT-1F, MT-G and MT-1H for Cd(+2)-exposed cells; and, MT-1F, MT-G and MT-1H for Zn(+2)-exposed cells. The results suggest that RWPE-1 cells may be a valuable system to define the interplay between Zn(+2) concentration, Cd(+2) exposure and MT in normal and malignant prostate epithelial cells.
Collapse
Affiliation(s)
- Amy L Albrecht
- Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND 58202, USA
| | | | | | | | | | | |
Collapse
|
21
|
Tan HT, Tan S, Lin Q, Lim TK, Hew CL, Chung MC. Quantitative and Temporal Proteome Analysis of Butyrate-treated Colorectal Cancer Cells. Mol Cell Proteomics 2008; 7:1174-85. [DOI: 10.1074/mcp.m700483-mcp200] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
|
22
|
Yan M, Song Y, Wong CP, Hardin K, Ho E. Zinc deficiency alters DNA damage response genes in normal human prostate epithelial cells. J Nutr 2008; 138:667-73. [PMID: 18356318 PMCID: PMC4152237 DOI: 10.1093/jn/138.4.667] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Zinc is an essential trace element for human health and is a critical component of many proteins and transcription factors involved in DNA damage response and repair. The prostate is known to accumulate high levels of zinc, but levels are markedly decreased with cancer development. We hypothesized that zinc plays a critical role in maintaining DNA integrity in the prostate and zinc deficiency would lead to increased DNA damage and altered DNA damage response mechanisms. To test this hypothesis, the goal of this study was to determine the effects of zinc deficiency on DNA damage and DNA repair mechanisms by examining changes in global gene expression and transcription factor binding abilities in normal prostate epithelial cells (PrEC). Increased single-strand DNA breaks (Comet assay) were observed in PrEC grown in zinc-deficient media compared with cells grown in zinc-adequate media for 7 d. Using Affymetrix HG-U133A gene chips, differential expression of genes involved in cell cycle, apoptosis, transcription, and DNA damage response and repair were identified with low cellular zinc. Among genes involved in DNA damage response and repair, tumor protein p73, MRE11 meiotic recombination 11 homolog A, X-ray repair complementing defective repair in Chinese hamster cells 4, and breast cancer 2, early onset were down-regulated and TP53 was up-regulated. Additionally, western blotting showed increased nuclear p53 protein expression with zinc deficiency. Despite increased p53 gene and nuclear protein expression, there was no significant change in p53 binding activity. Zinc deficiency also induced an increase in binding activity of transcription factors involved in regulating cell proliferation and apoptosis. Thus, zinc deficiency may compromise DNA integrity in the prostate by impairing the function of zinc-containing proteins.
Collapse
Affiliation(s)
| | | | | | | | - Emily Ho
- To whom correspondence should be addressed.
| |
Collapse
|
23
|
Abstract
Laser capture microdissection (LCM) offers a rapid and precise method of isolating and removing specified cells from complex tissues for subsequent analysis of their RNA, DNA, or protein content, thereby allowing assessment of the role of the cell type in the normal physiologic or disease process being studied. In this unit, protocols for the preparation of mammalian frozen tissues, fixed tissues, and cytologic specimens for LCM, including hematoxylin and eosin staining, are presented, as well as a protocol for the performance of LCM utilizing the PixCell I or II Laser Capture Microdissection System manufactured by Arcturus Engineering. Also provided is a protocol for tissue processing and paraffin embedding, and recipes for lysis buffers for the recovery of nucleic acids and proteins. The Commentary section addresses the types of specimens that can be utilized for LCM and approaches to staining of specimens for cell visualization. Emphasis is placed on the preparation of tissue or cytologic specimens as this is critical to effective LCM.
Collapse
Affiliation(s)
- A R Frost
- University of Alabama at Birmingham, Birmingham, Alabama, USA
| | | | | |
Collapse
|
24
|
Wei H, Desouki MM, Lin S, Xiao D, Franklin RB, Feng P. Differential expression of metallothioneins (MTs) 1, 2, and 3 in response to zinc treatment in human prostate normal and malignant cells and tissues. Mol Cancer 2008; 7:7. [PMID: 18208603 PMCID: PMC2265743 DOI: 10.1186/1476-4598-7-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Accepted: 01/21/2008] [Indexed: 11/10/2022] Open
Abstract
Background The disturbance of zinc homeostasis featured with a significant decrease of cellular zinc level was well documented to associate with the development and progression of human prostate malignancy. We have previously reported that zinc treatment induces prostate malignant cell apoptosis through mitochondrial pathway. Metallothionein (MT) is a major receptor/donor of zinc in the cells. However, the studies on the expression of MT in association with the prostate pathological and malignant status are very limited, and the zinc regulation of MT isoform expression in prostate cells remains elusive. The goals of this study were to define the expression of endogenous MTs, the isoforms of MT 1, 2, 3 at both messenger ribonucleic acid (mRNA) and protein levels; and to investigate the zinc effect on MT expression in normal prostate, benign prostatic hyperplasia (BPH) and malignant PC-3 cells, and in relevant human tissues. Cellular MT proteins were detected by immunohistochemistry, fluorescence staining and Western blot analysis; reverse transcription polymerase chain reaction (RT-PCR) was used to determine the MT isoform-specific mRNAs. Results Our results demonstrated a significant suppression of endogenous levels of MT1/2 in malignant PC-3 cells (95% reduction compared to the normal prostate cells) and in human adenocarcinoma tissues (73% MT1/2 negative). A moderate reduction of MT1/2 expression was observed in BPH. Zinc treatment remarkably induced MT1/2 expression in PC-3 and BPH cells, which was accordant with the restored cellular zinc level. MT 3, as a growth inhibitory factor, was detected and up-regulated by zinc mainly in BPH cells. Conclusion This study provided evidence of the association of attenuated MT1/2 with prostate tumor progression, and the zinc induction of MT1/2 expression resulting in cellular zinc restoration. The results suggest the potential of MT1/2 as a candidate biomarker for prostate cancer and the utilization of zinc in prostate cancer prevention and treatment.
Collapse
Affiliation(s)
- Hua Wei
- Department of Biomedical Sciences, Dental School, University of Maryland at Baltimore, Maryland, USA.
| | | | | | | | | | | |
Collapse
|
25
|
Tao X, Zheng JM, Xu AM, Chen XF, Zhang SH. Downregulated expression of metallothionein and its clinicopathological significance in hepatocellular carcinoma. Hepatol Res 2007; 37:820-7. [PMID: 17517078 DOI: 10.1111/j.1872-034x.2007.00113.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AIM Metallothionein (MT) protein is related to different stages of development and progression of various tumors in humans. The aim of the present study was to investigate expression and localization of MT and their association with clinicopathological characteristics in hepatocellular carcinoma (HCC). METHODS Histological specimens of 400 HCC with corresponding non-cancerous liver tissues were stained for MT (E9), P53 and Ki-67 by immunohistochemical staining using tissue microarrays. RNA expression of MT-1X and MT-2A isoforms was determined by real-time reverse transcription-polymerase chain reaction in a set of independent samples of 161 HCC. RESULTS Downregulated expression of MT at both mRNA and protein levels was detected in HCC, compared with non-cancerous liver tissues. The frequencies of MT positivity were significantly lower in cases with positive hepatitis B surface antigen than in those with negative hepatitis B surfaceantigen (P = 0.042). The positive rate of MT expression was more frequent in tumors </=2 cm than in tumors >2 cm in diameter (P = 0.007). There was a tendency for MT expression to decrease with the progression of histological grade. Mainly nuclear expression of MT correlated with poorly differentiated HCC. No statistical correlation was found between P53, Ki-67 and MT expression. CONCLUSIONS Downregulated expression of MT in HCC may play a role in hepatocarcinogenesis and be a marker of hepatocellular differentiation. Hepatitis B virus infection may be correlated to downregulated expression of MT. The mainly nuclear MT immunostaining may reflect an aggressive behavior in poorly differentiated HCC.
Collapse
Affiliation(s)
- Xia Tao
- Department of Pharmacy, Changzheng Hospital, Shanghai, China
| | | | | | | | | |
Collapse
|
26
|
Abstract
Metallothioneins (MTs) are proteins known to be involved in defense mechanisms against heavy metals and reactive oxygen species. In human, more than ten MT isoform genes have been identified, in contrast to much fewer isoforms in other mammalian species. The increased number of isoforms in human may have some biological significance; for example, isoforms may have been functionally differentiated to deal with various environmental factors in the evolutional process. However, we know little about the functions of the individual MT isoforms. To clarify functional differences between human MT isoforms, we developed a method to determine individual isoform mRNA levels using real-time polymerase chain reaction (PCR), and studied responses of the isoform genes against heavy metals (Zn, Cd, Cu) and As in HeLa cells. These metals induced all MT isoforms except for MT-1A by Cu, though their induced levels were different. Furthermore, these metals preferentially induced isoforms MT-2A and MT-1X suggesting that these isoforms may be important in protecting from their cytotoxicity.
Collapse
Affiliation(s)
- Nobuhiko Miura
- Mechanism of Health Effect Research Group, National Institute of Occupational Safety and Health, Kawasaki, Japan.
| | | |
Collapse
|
27
|
Wang R, Sens DA, Albrecht A, Garrett S, Somji S, Sens MA, Lu X. Simple method for identification of metallothionein isoforms in cultured human prostate cells by MALDI-TOF/TOF mass spectrometry. Anal Chem 2007; 79:4433-41. [PMID: 17497826 PMCID: PMC4276256 DOI: 10.1021/ac062309s] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The present paper describes a rapid method for identification and characterization of human metallothionein (MT) isoforms in complex cell cultures using high-resolution matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF). In the proposed method, the sample preparation of MTs from cultured cells is both simple and fast. It is accomplished by trypsin cleavage of cell proteins into small peptide species, the majority of which are subsequently removed by gel filtration using beads with an exclusion limit of 4000 Da. In contrast to most cell proteins, MTs remain intact (undigested) upon being treated with trypsin, being excluded by the gel beads and thus recovered by low-speed centrifugation. To identify the protein constitutes of the MT preparation, the MT sample is divided into two parts, one for intact protein accurate mass measurement, the other for tryptic digestion followed by MS and MS/MS analyses. In the latter case, the MT proteins are denatured by the addition of EDTA which strips heavy metals from MTs and renders them susceptible to tryptic digestion. The obtained accurate mass with the unique peptide sequences of each MT isoform allows for unambiguous identification of MT isoforms in the prepared mixture. The method has been applied to RWPE-1 cells derived from normal human prostate epithelium. Four MT isoforms, 1E, 1G, 1X, and 2A, have been confidently identified, being primarily acetylated at N-termini. These results are in agreement with the expression of MT mRNAs in RWPE-1 cells determined by real-time reverse-transcription polymerase chain reaction (RT-PCR).
Collapse
Affiliation(s)
- Rongying Wang
- Department of Pathology, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
- Proteomics Core Facility, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
| | - Donald A. Sens
- Department of Pathology, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
| | - Amy Albrecht
- Department of Pathology, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
| | - Scott Garrett
- Department of Pathology, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
| | - Seema Somji
- Department of Pathology, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
| | - Mary Ann Sens
- Department of Pathology, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
| | - Xiaoning Lu
- Department of Pathology, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
- Proteomics Core Facility, School of Medicine and Health Science, University of North Dakota, Grand Forks, ND 58202
- To whom correspondence should be addressed: Xiaoning Lu, University of North Dakota, SOMHS, 501 N. Columbia Road, RM 3573, Grand Forks, ND 58202-9037, Phone: 701-777-0389, Fax: 701-777-3108,
| |
Collapse
|
28
|
Liu ZM, Chen GG, Shum CKY, Vlantis AC, Cherian MG, Koropatnick J, van Hasselt CA. Induction of functional MT1 and MT2 isoforms by calcium in anaplastic thyroid carcinoma cells. FEBS Lett 2007; 581:2465-72. [PMID: 17485079 DOI: 10.1016/j.febslet.2007.04.049] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Revised: 04/18/2007] [Accepted: 04/23/2007] [Indexed: 10/23/2022]
Abstract
Metallothionein (MT) expression in carcinogenesis of thyrocytes is unknown. We demonstrated that cadmium induced transcription of all functional MT-1 and MT-2 isoforms and promoted the cell cycle from the G1 to the S phase in thyroid cancer cells, which can be suppressed by the ERK inhibitor. Cadmium exposure stimulated intracellular calcium and the phosphorylation of ERK1/2. Therefore, a common pathway initiated by a rapid rise in calcium and followed by calcium-mediated activation of ERK is involved in the transcriptional induction of functional MT1 and MT2 isoforms and in the progression of the cell cycle in thyroid cancer cells exposed to cadmium.
Collapse
Affiliation(s)
- Zhi-Min Liu
- Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong, China
| | | | | | | | | | | | | |
Collapse
|
29
|
Anderson PW, Tennant BC, Lee Z. Cross-species hybridization of woodchuck hepatitis virus-induced hepatocellular carcinoma using human oligonucleotide microarrays. World J Gastroenterol 2006; 12:4646-51. [PMID: 16937433 PMCID: PMC4087827 DOI: 10.3748/wjg.v12.i29.4646] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To demonstrate the feasibility of using woodchuck samples on human microarrays, to provide insight into pathways involving positron emission tomography (PET) imaging tracers and to identify genes that could be potential molecular imaging targets for woodchuck hepatocellular carcinoma.
METHODS: Labeled cRNA from woodchuck tissue samples were hybridized to Affymetrix U133 plus 2.0 GeneChips®. Ten genes were selected for validation using quantitative RT-PCR and literature review was made.
RESULTS: Testis enhanced gene transcript (BAX Inhibitor 1), alpha-fetoprotein, isocitrate dehydrogenase 3 (NAD+) beta, acetyl-CoA synthetase 2, carnitine palmitoyltransferase 2, and N-myc2 were up-regulated and spermidine/spermine N1-acetyltransferase was down-regulated in the woodchuck HCC. We also found previously published results supporting 8 of the 10 most up-regulated genes and all 10 of the 10 most down-regulated genes.
CONCLUSION: Many of our microarray results were validated using RT-PCR or literature search. Hence, we believe that woodchuck HCC and non-cancerous liver samples can be used on human microarrays to yield meaningful results.
Collapse
Affiliation(s)
- Paul W Anderson
- Department of Radiology, University Hospitals of Cleveland, Cleveland, OH 44106, USA
| | | | | |
Collapse
|
30
|
Smith DJ, Jaggi M, Zhang W, Galich A, Du C, Sterrett SP, Smith LM, Balaji KC. Metallothioneins and resistance to cisplatin and radiation in prostate cancer. Urology 2006; 67:1341-7. [PMID: 16765200 DOI: 10.1016/j.urology.2005.12.032] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Revised: 11/15/2005] [Accepted: 12/14/2005] [Indexed: 10/24/2022]
Abstract
OBJECTIVES The metallothioneins (MTs) are a family of small molecular weight trace metal and free radical scavenging proteins well established to play a role in the resistance to chemotherapy and radiotherapy in human cancers. MT gene expression is upregulated in response to the presence of metal ions such as zinc. Because prostatic tissue has the greatest concentration of zinc in the human body, in this study we analyzed the effect of MT induction by zinc in prostate cancer (PCa). METHODS The activation of MT gene expression in response to zinc treatment in LNCaP and C4-2 PCa cells was shown by Western blotting and DNA microarray analysis. Chemotherapy and radiation sensitivity assays of cells after treatment with cisplatin or radiation were performed in the presence, or absence, of 150 microM ZnSO4, and cell viability was measured after 72 hours by MTS viability and clonogenic and flow cytometry assays. The experiments were repeated three times and the data analyzed. RESULTS Increasing concentrations of ZnSO4 upregulated MT expression in a dose-dependent manner. Microarray analysis demonstrated a specific increase in MT expression. Cells treated with zinc demonstrated a significantly decreased sensitivity to cisplatin and radiotherapy compared with controls (P <0.05). CONCLUSIONS Our data have confirmed that treatment of PCa with zinc causes an increase in MT expression, which is significantly associated with resistance to cisplatin chemotherapy and radiotherapy in PCa. Therapeutic targeting of MT may therefore provide a means to overcome resistance to radiotherapy and cisplatin chemotherapy in PCa.
Collapse
Affiliation(s)
- David J Smith
- Department of Surgery, Division of Urology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Chung MJ, Kang AY, Lee KM, Oh E, Jun HJ, Kim SY, Auh JH, Moon TW, Lee SJ, Park KH. Water-soluble genistin glycoside isoflavones up-regulate antioxidant metallothionein expression and scavenge free radicals. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2006; 54:3819-26. [PMID: 16719502 DOI: 10.1021/jf060510y] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Genistin has antioxidant activities; however, its insolubility in water often limits its biological availability in vivo. Using a novel transglycosylation process, the solubility of genistin glycosides was increased 1000 to 10000-fold, but it was not known whether these modified genistin glycosides maintained antioxidant activity. We found that both genistin and its glycosides similarly up-regulated the transcription of several metallothionein (MT) antioxidant genes (MT1A, MT2A, MT1E, and MT1X), as well as the glucose 6-phosphate dehydrogenase (G6PD) gene in HepG2 cells. This gene induction was mediated by the sequestration of zinc in the cytosol, which up-regulated the metal-responsive transcription factor-1 (MTF-1) that induced MT gene expression. Although not as effective as ascorbic acid, genistin glycosides possessed slightly greater reducing power than genistin. We concluded that genistin and genistin glycosides have a direct antioxidant effect and an indirect antioxidant effect, perhaps via induction of MT by activity of MTF-1.
Collapse
Affiliation(s)
- Mi Ja Chung
- Division of Food Science, College of Life and Environmental Sciences, Institute of Biomedical Sciences and Food Safety, Korea University, Seoul 136-713, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
El Sharkawy SL, Abbas NF, Badawi MA, El Shaer MA. Metallothionein isoform II expression in hyperplastic, dysplastic and neoplastic prostatic lesions. J Clin Pathol 2006; 59:1171-4. [PMID: 16574721 PMCID: PMC1860510 DOI: 10.1136/jcp.2005.033746] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND Metallothionein is a low-molecular-weight cysteine-rich protein that has the ability to bind and sequestrate heavy metal ions. It is associated with metalloregulatory functions such as cell proliferation, growth and differentiation. AIMS To investigate the expression of metallothionein in hyperplastic, dysplastic and neoplastic prostatic lesions and to correlate its expression with histological grade of prostatic carcinoma. METHOD The study was carried out on formalin-fixed and paraffin-wax-embedded tissue blocks from 8 patients with benign prostatic hyperplasia, 6 patients with prostatic intraepithelial neoplasia (PIN) and 30 patients with prostatic carcinoma, using the streptavidin-biotin technique. The histological grade was defined and the carcinomas were divided into low-grade (Gleason Score 2-4), 12 moderate grade (Gleason Score 5-6) and 10 high-grade (Gleason Score 7-10) carcinomas. RESULTS Patchy metallothionein staining of epithelial cells was observed in normal and benign prostatic tissues. All cases of PIN and 20 of 30 patients with prostatic carcinoma showed positive staining for metallothionein. Metallothionein expression considerably increased from low-grade to high-grade tumours. The proportion of cells staining positively for metallothionein was directly correlated with histological grade of prostatic carcinoma. The epithelial cells lack uniformity in staining intensity, but the percentage of strongly positive cells increased with the histological grade of prostatic carcinoma. CONCLUSIONS The high incidence of metallothionein expression in PIN in our study suggests that it is associated with early prostate tumorigenesis. Also, metallothionein expression was directly correlated with the histological grade of prostatic carcinoma, suggesting that metallothionein may be a useful marker for predicting the prognosis of prostate cancer.
Collapse
Affiliation(s)
- S L El Sharkawy
- Pathology Department, Medical Division, National Research Centre, Dokki Giza, Egypt
| | | | | | | |
Collapse
|
33
|
Garrett SH, Park S, Sens MA, Somji S, Singh RK, Namburi VBRK, Sens DA. Expression of metallothoinein isoform 3 is restricted at the post-transcriptional level in human bladder epithelial cells. Toxicol Sci 2005; 87:66-74. [PMID: 15958653 DOI: 10.1093/toxsci/kfi231] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
This study was designed to define the effect that overexpression of MT-3 would have on a cell culture model of bladder urothelium. Stable and inducible transfection was used to achieve overexpression of the MT-3 gene in the UROtsa cell line. When the UROtsa cells were stably transfected with the MT-3 coding sequence, there was highly elevated expression of MT-3 mRNA, but no MT-3 protein. An inducible vector showed that low basal levels of MT-3 mRNA and protein could be produced, but that induction only increased MT-3 mRNA and not protein. The clones expressing low basal levels of MT-3 protein also had reduced growth rates compared to control cells. Site directed mutagenesis was used to produce an MT-3 coding sequence where the prolines in positions 7 and 9 were converted to threonines. When this altered MT-3 was stably transfected into the UROtsa cells, the cells were able to accumulate the mutated form of the MT-3 protein. These studies show that MT-3 protein expression is inhibited by post-transcriptional control in the urothelial cell. Modifying the MT-3 protein to resemble the MT-1 isoform removes this component of post-transcriptional control and allows accumulation of the mutated MT-3 protein. The altered sequence involved in post-transcriptional control of MT-3 protein expression is the same sequence implicated in the neuronal growth inhibitory activity associated specifically with the MT-3 isoform of the MT gene family.
Collapse
Affiliation(s)
- Scott H Garrett
- Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota 58202, USA
| | | | | | | | | | | | | |
Collapse
|
34
|
Gurel V, Sens DA, Somji S, Garrett SH, Weiland T, Sens MA. Post-Transcriptional Regulation of Metallothionein Isoform 1 and 2 Expression in the Human Breast and the MCF-10A Cell Line. Toxicol Sci 2005; 85:906-15. [PMID: 15788722 DOI: 10.1093/toxsci/kfi155] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Studies have shown, using immunohistochemical staining, that the MT-1 and MT-2 proteins (MT-1/2) are overexpressed in a substantial subset of ductal breast cancers, that overexpression occurs early in the disease process, and that this overexpression is indicative of a poor prognosis. Normal ductal breast epithelium fails to immunostain for the MT-1/2 protein, whereas the myoepithelial cells of the ducts stain intensely. There is no information regarding the expression of the mRNAs for the eight active MT-1 and MT-2 genes in normal breast duct epithelium. Microdissection of normal breast samples was used to obtain total RNA from enriched populations of ductal epithelium and myoepithelium. Analysis by reverse-transcription polymerase chain reaction (RT-PCR) demonstrated that the identity of the MT isoform-specific genes expressed (MT-2A and MT-1X) and their relative levels of expression were similar between the myoepithelial and ductal components. These findings indicate that the ductal and myoepithelial components express similar amounts of MT-2A and MT-1X mRNAs, but that they have distinctly different expression of the MT-1/2 protein. Confluent cultures of MCF-10A breast epithelial cells were exposed to Cd(+2) to test for evidence of post-transcriptional regulation of MT-1/2 protein accumulation in ductal epithelium. It was demonstrated that Cd(+2) elicited only a marginal induction of MT-1E, MT-1X, or MT-2A mRNAs, whereas, there was a marked increase in MT-1/2 protein, reaching levels of 6% of total cell protein under conditions of extended exposure. This study suggests that the mechanism underlying the finding of increased MT-1/2 protein expression in ductal breast cancer may involve, to some degree, the post-transcriptional regulation of MT-1/2 protein expression.
Collapse
Affiliation(s)
- Volkan Gurel
- Department of Pathology School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota 58202, USA
| | | | | | | | | | | |
Collapse
|
35
|
Yi Y, Mirosevich J, Shyr Y, Matusik R, George AL. Coupled analysis of gene expression and chromosomal location. Genomics 2005; 85:401-12. [PMID: 15718107 DOI: 10.1016/j.ygeno.2004.11.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2004] [Accepted: 11/16/2004] [Indexed: 01/05/2023]
Abstract
Microarray technology can be used to assess simultaneously global changes in expression of mRNA or genomic DNA copy number among thousands of genes in different biological states. In many cases, it is desirable to determine if altered patterns of gene expression correlate with chromosomal abnormalities or assess expression of genes that are contiguous in the genome. We describe a method, differential gene locus mapping (DIGMAP), which aligns the known chromosomal location of a gene to its expression value deduced by microarray analysis. The method partitions microarray data into subsets by chromosomal location for each gene interrogated by an array. Microarray data in an individual subset can then be clustered by physical location of genes at a subchromosomal level based upon ordered alignment in genome sequence. A graphical display is generated by representing each genomic locus with a colored cell that quantitatively reflects its differential expression value. The clustered patterns can be viewed and compared based on their expression signatures as defined by differential values between control and experimental samples. In this study, DIGMAP was tested using previously published studies of breast cancer analyzed by comparative genomic hybridization (CGH) and prostate cancer gene expression profiles assessed by cDNA microarray experiments. Analysis of the breast cancer CGH data demonstrated the ability of DIGMAP to deduce gene amplifications and deletions. Application of the DIGMAP method to the prostate data revealed several carcinoma-related loci, including one at 16q13 with marked differential expression encompassing 19 known genes including 9 encoding metallothionein proteins. We conclude that DIGMAP is a powerful computational tool enabling the coupled analysis of microarray data with genome location.
Collapse
Affiliation(s)
- Yajun Yi
- Division of Genetic Medicine, Department of Medicine, Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, TX 37232, USA
| | | | | | | | | |
Collapse
|
36
|
Yin H, Smith M, Glass J. Stable expression of C/EBPalpha in prostate cancer cells down-regulates metallothionein and increases zinc-induced toxicity. Prostate 2005; 62:209-16. [PMID: 15389791 DOI: 10.1002/pros.20136] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The transcription factor C/EBPalpha regulates terminal differentiation of various cell types. C/EBPalpha is expressed in prostate epithelium but its role in prostate development and malignant transformation is unknown. In examining the effect of forced expression of C/EBPalpha on the global gene expression profile in prostate cancer cells, we found that C/EBPalpha significantly decreased the RNA level of metallothioneins (MTs). METHODS The prostate cancer cell lines DU145, LNCaP, and PC3 with stable overexpression of C/EBPalpha were established with a retroviral expression system. MT expression was assayed by Western blot analysis and with the MT promoter in a plasmid using luciferase as a reporter. RESULTS Under basal conditions and in response to zinc, forced overexpression of C/EBPalpha decreased expression of MT isoforms 1A, B, F, and H, IIA and III. Following zinc exposure C/EBPalpha inhibited MT promoter activity by 1.5-2.5-fold. Overexpression of C/EBPalpha led to increased cytotoxicity of zinc at concentration of 150 microM in DU145 and LNCaP cells. CONCLUSIONS Our data demonstrated that expression of MTs in prostate cancer cells is inhibited by C/EBPalpha and the effect may have functional significance in regulating the growth of prostate cancer cells and the response of these cells to environment stresses.
Collapse
Affiliation(s)
- Hong Yin
- Feist-Weiller Cancer Center and Department of Medicine, Louisiana State University, Shreveport, Louisiana 71130, USA
| | | | | |
Collapse
|
37
|
Jin R, Huang J, Tan PH, Bay BH. Clinicopathological significance of metallothioneins in breast cancer. Pathol Oncol Res 2004; 10:74-9. [PMID: 15188022 DOI: 10.1007/bf02893459] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2004] [Accepted: 05/21/2004] [Indexed: 02/06/2023]
Abstract
Metallothioneins (MTs) are a family of metal binding proteins that play an important role in maintaining transition metal ion homoeostasis, redox balance in the cell and fundamental cellular processes such as proliferation and apoptosis. In humans, there are 4 groups of MT proteins which are encoded by 10 functional MT isoforms. In breast tissues, MT is primarily expressed in myoepithelial and malignant epithelial cells. Immunohistochemical studies have revealed that 26% to 100% of invasive ductal breast cancers express the MT protein. The MT-1F and MT-2A isoforms have been reported to be associated with higher histological grade in breast cancer, whereas higher MT-1E mRNA expression was found in estrogen receptor-negative tumors compared to their estrogen receptor-positive counterparts. A number of studies have shown that MT expression in breast cancer is associated with poorer prognosis. In addition, metallothionein expression may have a potential role in protecting the breast cancer cell from chemotherapeutic threats to survival.
Collapse
Affiliation(s)
- Rongxian Jin
- Department of Anatomy, National University of Singapore
| | | | | | | |
Collapse
|
38
|
Hasumi M, Suzuki K, Matsui H, Koike H, Ito K, Yamanaka H. Regulation of metallothionein and zinc transporter expression in human prostate cancer cells and tissues. Cancer Lett 2003; 200:187-95. [PMID: 14568174 DOI: 10.1016/s0304-3835(03)00441-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Prostate glands contain heavy metals such as zinc and cadmium, and epidemiological studies showed that both metals were associated with prostate cancer development. To understand the heavy metal metabolism in prostate glands, we investigated the regulation of metallothionein (MT), metal-responsive promoter element-binding transcription factor (MTF) and zinc transporter (ZnT) in human prostate cells and tissues. Growth of human prostate cancer cells, LNCaP and PC-3 cells, was suppressed by zinc or cadmium treatment in a dose-dependent manner. LNCaP cells expressed MT-1A, 1X and 2A mRNA, and PC-3 cells expressed MT-1X and 2A mRNA. Zinc or cadmium treatment up-regulated MTs, MTF-1 and ZnT-1 gene expression levels in both cell lines. In PC-3 cells, ZnT-1 protein was detected, and was up-regulated by the metal treatment. Human prostate cancer tissues expressed significantly lower levels of ZnT-1 gene in comparison with hyperplastic tissues. We demonstrated the ZnT-1 expression in human prostate for the first time. The present study showed that heavy metal-metabolizing proteins were involved in human prostate homeostasis, and that the metal metabolizing system might be different in malignant tissues.
Collapse
Affiliation(s)
- Masaru Hasumi
- Department of Urology, Gunma University School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | | | | | | | | | | |
Collapse
|
39
|
Rao PS, Jaggi M, Smith DJ, Hemstreet GP, Balaji KC. Metallothionein 2A interacts with the kinase domain of PKCmu in prostate cancer. Biochem Biophys Res Commun 2003; 310:1032-8. [PMID: 14550308 DOI: 10.1016/j.bbrc.2003.09.118] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Prostate cancer (PC) patients die from progression to androgen independence (AI) and chemoresistance (CR). Protein kinase Cmu (PKCmu) a novel member of the PKC family of signal transduction proteins is downregulated in AI PC. Studying PKCmu interactors in the yeast two-hybrid system identified metallothionein 2A (MT 2A) as an interactor of PKCmu kinase domain (KD) in PC, which was quantified by beta-gal assay, confirmed in PC cells by immunoprecipitation, and PKCmu-MT 2A co-localization in vivo by immunofluorescence studies. PKCmu domain interaction studies revealed that MT 2A interacted strongly with KD, relatively weakly with C1, and failed to interact with C2, PH or kinase mutant domains. Peptide library and in silico analysis strongly suggest that MT 2A is a novel substrate of PKCmu and our data indicate that the PKCmu-MT 2A interaction depends on PKCmu kinase activity. Because metallothioneins are associated with cell proliferation and CR, the PKCmu-MT 2A interaction may contribute to CR and/or AI in PC.
Collapse
Affiliation(s)
- Prema S Rao
- Division of Urological Surgery, Department of Surgery, University of Nebraska Medical Center, Omaha, NE 68198-2360, USA
| | | | | | | | | |
Collapse
|
40
|
Tai SK, Tan OJK, Chow VTK, Jin R, Jones JL, Tan PH, Jayasurya A, Bay BH. Differential expression of metallothionein 1 and 2 isoforms in breast cancer lines with different invasive potential: identification of a novel nonsilent metallothionein-1H mutant variant. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 163:2009-19. [PMID: 14578200 PMCID: PMC1892412 DOI: 10.1016/s0002-9440(10)63559-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/24/2003] [Indexed: 12/14/2022]
Abstract
Metallothionein (MT), a low-molecular weight protein with pleiotropic functions, is believed to play an important role in tumorigenesis. The aim of this study was to compare the expression of functional MT-1 and MT-2 mRNA isoforms in five breast cancer cell lines ranging from noninvasive MCF7 breast cancer cells to highly aggressive MDA-MB-231 breast cancer cells together with breast myoepithelial cells in vitro by conventional semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and quantitative real-time RT-PCR. The MT-2A isoform was observed to be differentially upregulated in the invasive phenotype. The MT-1E isoform was found to be present in estrogen receptor-negative breast cancer cell lines (MDA-MB-231 and Hs578T) but not detectable in the estrogen receptor-positive cell lines (T47D, MCF7, and ZR75-1 cells). Only the myoepithelial cells exhibited the presence of the MT-1G transcript. Direct sequencing of the RT-PCR products revealed the occurrence of a variant MT-1H isoform with changes in amino acid residues in the protein sequence and notable differences in the predicted secondary protein structure. The observations in this study are relevant to the development of novel approaches to metastatic breast cancer disease, and may herald the search for novel MT mutants and the elucidation of their biological roles.
Collapse
Affiliation(s)
- Siew-Kian Tai
- Department of Microbiology, Human Genome Laboratory, Faculty of Medicine, National University of Singapore, 4 Medical Drive, S-117 597 Singapore, Republic of Singapore
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Gurel V, Sens DA, Somji S, Garrett SH, Nath J, Sens MA. Stable transfection and overexpression of metallothionein isoform 3 inhibits the growth of MCF-7 and Hs578T cells but not that of T-47D or MDA-MB-231 cells. Breast Cancer Res Treat 2003; 80:181-91. [PMID: 12908821 DOI: 10.1023/a:1024520801262] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The third isoform of metallothionein (MT-3) is overexpressed in some breast cancers and its expression is associated with a poor disease outcome. In the PC-3 prostate cancer cell line, MT-3 expression has been shown to inhibit cell growth and increase drug resistance. The goal of the present study was to determine if MT-3 overexpression would influence the growth of human breast cancer cell lines. To determine this, the coding sequence of the MT-3 gene was stably transfected into two estrogen receptor positive (MCF-7 and T-47D) and two estrogen receptor negative cell lines (Hs578T and MDA-MB-231) having no basal expression of MT-3. Cell growth was determined by counting DAPI-stained nuclei, cadmium resistance by the colony formation assay, MT mRNA expression by RT-PCR, and MT protein by immuno-blot. It was demonstrated that MCF-7 and Hs578T cells that overexpress the MT-3 gene were growth inhibited compared to untransfected cells. In contrast, T-47D and MDA-MB-231 cells that overexpress MT-3 were not growth inhibited. Stable transfection of the MT-1E gene had no effect on the growth of any of the four cell lines. It was also demonstrated that the overexpression of both MT-3 and MT-1E only increased the resistance of MCF-7 cells to Cd(+2). In all instances, stable transfection of the MT-3 or MT-1E gene had no effect on the expression of the other MT isoforms. The study shows that MT-3 can influence the growth of some breast cancer cell lines.
Collapse
Affiliation(s)
- Volkan Gurel
- Department of Pathology, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND 58202-9037, USA
| | | | | | | | | | | |
Collapse
|
42
|
Gaddipati JP, Rajeshkumar N, Grove JC, Maharaj SVM, Centeno JA, Maheshwari RK, Jonas WB. Low-Dose Cadmium Exposure Reduces Human Prostate Cell Transformation in Culture and Up-Regulates Metallothionein and MT-1G mRNA. NONLINEARITY IN BIOLOGY, TOXICOLOGY, MEDICINE 2003; 1:199-212. [PMID: 19330122 PMCID: PMC2651606 DOI: 10.1080/15401420391434333] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Chronic low-level exposure to environmental toxins, including cadmium (Cd), is a growing problem in the industrialized world. One promising strategy for protection from these toxins is the use of low-dose exposure of environmental chemicals to induce cell tolerance and recovery, a phenomenon known as "protective hormesis". Hormetic [low-dose stimulatory] effects occur in a variety of systems and with a number of chemicals. Cd is a potent carcinogen in rodents and has also been linked to human lung and prostate cancers. In the present study, we have evaluated the protective effects of low and ultra-low dose, long-term Cd exposure in the normal human prostate cells, RWPE-1. Cells were exposed to low and ultra-low doses (0, 0 (S(-36)), 10(-6), 10(-7), 10(-18), 10(-21), 10(-32), or 10(-36)M) of Cd for 20 weeks followed by treatment with 10(-5)M Cd for another 8 weeks. Continuous exposure of RWPE-1 cells to 10(-5)M Cd results in malignant transformation. However, cells pretreated with low and ultra-low doses of Cd had delayed transformation compared with controls. In addition, the number of transformed cell mounds was lower in pretreated cells indicating that low and ultra-low dose exposure had protective effects against high-dose Cd induced carcinogenesis. The expression of metallothionein (MT), the primary Cd detoxification protein, was induced by low-dose exposure to Cd and maintained during the 20 weeks. In addition, MT-1G mRNA was up-regulated 2- to 3-fold by low-dose and ultralow-dose Cd exposures and may be the mechanism of protective hormesis in this model. MT-1G mRNA might also serve as a biological indicator of very low-dose environmental Cd exposure.
Collapse
Affiliation(s)
- Jaya P. Gaddipati
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, MD
| | - N.V. Rajeshkumar
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, MD
| | - Jason C. Grove
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, MD
| | | | - Jose A. Centeno
- Department of Environmental and Toxicologic Pathology, Armed Forces Institute of Pathology, Washington, D.C
| | - Radha K. Maheshwari
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, MD
| | - Wayne B. Jonas
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, MD
- Samueli Institute for Information Biology, Alexandria, VA, USA
| |
Collapse
|
43
|
Minami T, Ichida S, Kubo K. Study of metallothionein using capillary zone electrophoresis. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 781:303-11. [PMID: 12450665 DOI: 10.1016/s1570-0232(02)00496-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Metallothioneins (MTs) have many different functions in tissues, but the roles of individual isoforms are still not entirely clear. Capillary zone electrophoresis (CZE) is a powerful method for the separation of substances because of its small sample requirement, rapid analysis, high sensitivity and high resolution. The separation and identification of mammalian MT-1, MT-2, and MT-3 and class III MTs by CZE has been reported. Uncoated and polyacrylamide-coated capillary tubes were recently used for the separation of MTs, and a UV detector is usually employed for observations of peaks of MTs. Small changes to the structure and metal components of MTs are reflected in the migration times of the peaks. N-acetylated and non-acetylated MTs can be separated and identified by CZE-mass spectrometry (MS). In addition, metal complexes with MTs can be characterized by CZE-proton-induced X-ray emission (PIXE) detector and CZE-inductively coupled plasma (ICP)-MS. For the quantification of an MT isoform, the peak area of UV absorption is used, but the technique has problems. One is lack of a purified isoform standard. The other is the need for a suitable internal standard substance. CZE-ICP-isotope dilution (ID)-MS is also reported to be able to quantify MT isoforms. CZE combined with other techniques is very effective for separation and quantitative and qualitative analyses of MT isoforms in biological materials.
Collapse
Affiliation(s)
- Takeshi Minami
- Laboratory of Environmental Biology, Department of Life Science, School of Science and Engineering, Kinki University, 3-4-1 Kowakae, Higashiosaka, Osaka 577-8502, Japan.
| | | | | |
Collapse
|
44
|
Abstract
Histologic and cytologic changes are central to the diagnosis and classification of many disease processes, particularly neoplasms. The correlation of these changes with genomics, proteomics, and molecular pathways entails refined microdissection techniques that are frequently used to procure a pure population of cells from complex tissue. Here we review the past, present, and future of some of these new advances in microdissection techniques including manual techniques, laser microdissection, laser capture microdissection, and laser catapulting.
Collapse
Affiliation(s)
- Isam A Eltoum
- Departments of Pathology, Cell Biology and Surgery, and the UAB Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama 35233, USA
| | | | | |
Collapse
|
45
|
Dutta R, Sens DA, Somji S, Sens MA, Garrett SH. Metallothionein isoform 3 expression inhibits cell growth and increases drug resistance of PC-3 prostate cancer cells. Prostate 2002; 52:89-97. [PMID: 12111700 DOI: 10.1002/pros.10097] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The third isoform of metallothionein (MT-3) is overexpressed in prostate cancers and PIN lesions. The expression of MT-3 is highly variable but appears to correlate to Gleason score. The goal of the present study was to determine the effect of MT-3 overexpression on the growth of the PC-3 prostate cancer cell line. METHODS PC-3 cells were stably transfected with either the MT-3 or MT-1E gene. Cell growth was determined by counting DAPI-stained nuclei, drug resistance by the colony formation assay, MT mRNA expression by reverse transcriptase-polymerase chain reaction, and MT protein by immunoblot. RESULTS PC-3 cells that overexpress the MT-3 gene are growth inhibited compared with either untransfected cells, cells with blank vector, or cells with similar overexpression of the MT-1E gene. Furthermore, increased chemotherapeutic drug resistance occurred in PC-3 clones derived from MT-3- and MT-1E-transfected cells. CONCLUSION The overexpression of MT-3 can influence the growth and chemotherapeutic drug resistance of the PC-3 prostate cancer cell line.
Collapse
Affiliation(s)
- Rana Dutta
- Program in Genetics and Developmental Biology, West Virginia University, Morgantown, West Virginia 26506-9251, USA
| | | | | | | | | |
Collapse
|
46
|
Kim D, Garrett SH, Sens MA, Somji S, Sens DA. Metallothionein isoform 3 and proximal tubule vectorial active transport. Kidney Int 2002; 61:464-72. [PMID: 11849386 DOI: 10.1046/j.1523-1755.2002.00153.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Metallothionein isoform 3 (MT-3) is expressed in the proximal tubule cells of the human kidney. The goal of the present study was to further characterize the basal expression of MT-3 in the proximal tubule and to determine if MT-3 participates in the maintenance of proximal tubule cell function. METHODS Expression of MT-3 mRNA was determined in the intact proximal tubule using microdissection and reverse transcription-polymerase chain reaction (RT-PCR). Basal expression of MT-3 mRNA and protein was determined in cultured human proximal tubule (HPT) cells and an immortalized proximal tubular cell line, HK-2 cells, using RT-PCR and immunoblotting. The MT-3 gene was stably transfected into the HK-2 cell line using the pcDNA3.1/Hygro (+) vector. RESULTS MT-3 mRNA was detected in the proximal tubule of the in situ kidney with relative expression in excess to that of the beta-actin housekeeping gene. The mortal HPT cells were shown to express both MT-3 mRNA and protein and to form domes, while immortal HK-2 cells were shown to have no expression of MT-3 mRNA and protein nor to form domes. The stable transfection of MT-3 in HK-2 restored MT-3 expression and dome formation to the HK-2 cells. CONCLUSIONS MT-3 mRNA is present in the human proximal tubule, and MT-3 expression is involved in the transport function of a human renal cell line that retains properties of the proximal tubule.
Collapse
Affiliation(s)
- Doyeob Kim
- Department of Surgery, Program in Genetics and Developmental Biology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia 26506-9251, USA
| | | | | | | | | |
Collapse
|
47
|
Sens MA, Somji S, Garrett SH, Beall CL, Sens DA. Metallothionein isoform 3 overexpression is associated with breast cancers having a poor prognosis. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 159:21-6. [PMID: 11438449 PMCID: PMC1850423 DOI: 10.1016/s0002-9440(10)61668-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The third isoform (MT-3) of the metallothionein gene family is unique in that it has a limited tissue distribution, is not induced by metals, has a neuronal growth inhibitory activity, and sequesters zinc more effectively under zinc-depleted conditions. The goal of the present study was to determine whether MT-3 was absent in normal breast tissue, was overexpressed in breast cancers, and if MT-3 overexpression would be associated with disease outcome. A combination of immunohistochemistry and reverse-transcription polymerase chain reaction was used to demonstrate that the normal breast had no detectable expression of MT-3 mRNA or protein. Using immunohistochemistry, it was shown that MT-3 was overexpressed in 25 of 34 cases of breast cancer. In all cases of positive staining, MT-3 was diffusely localized to the cytoplasm. The tumors from these 34 cases were divided as to outcome based on known 5-year survival, with 20 patients being disease free at 5 years (good outcome) and the other 14 having recurring disease within 5 years (bad outcome). When analyzed for MT-3 staining, it was shown that there was a trend for increased MT-3 immunoreactivity in the group having bad outcomes. However, when the tumor subgrouping was further defined on the basis of carcinoma in situ (CIS), there was a marked significant difference in MT-3 staining between patients with good and bad outcomes. Limited to DCIS, MT-3 staining was significantly increased in patients with bad outcomes compared to those with good outcomes. Thus, these studies demonstrate that MT-3 is overexpressed in selected breast cancers and that overexpression is associated with tumors having a poor prognosis.
Collapse
Affiliation(s)
- M A Sens
- Robert C. Byrd Health Sciences Center, Departments of Pathology and Urology, Program in Genetics and Developmental Biology, West Virginia University, Morgantown 26506-9203, USA.
| | | | | | | | | |
Collapse
|