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Bose SK, Gibson W, Giri S, Nath N, Donald CD. Angiotensin II up-regulates PAX2 oncogene expression and activity in prostate cancer via the angiotensin II type I receptor. Prostate 2009; 69:1334-42. [PMID: 19517575 DOI: 10.1002/pros.20980] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Paired homeobox 2 gene (PAX2) is a transcriptional regulator, aberrantly expressed in prostate cancer cells and its down-regulation promotes cell death in these cells. The molecular mechanisms of tumor progression by PAX2 over-expression are still unclear. However, it has been reported that angiotensin-II (A-II) induces cell growth in prostate cancer via A-II type 1 receptor (AT1R) and is mediated by the phosphorylation of mitogen activated protein kinase (MAPK) as well as signal transducer and activator of transcription 3 (STAT3). METHODS Here we have demonstrated that A-II up-regulates PAX2 expression in prostate epithelial cells and prostate cancer cell lines resulting in increased cell growth. Furthermore, AT1R receptor antagonist losartan was shown to inhibit A-II induced PAX2 expression in prostate cancer. Moreover, analysis using pharmacological inhibitors against MEK1/2, ERK1/2, JAK-II, and phospho-STAT3 demonstrated that AT1R-mediated stimulatory effect of A-II on PAX2 expression was regulated in part by the phosphorylation of ERK1/2, JAK II, and STAT3 pathways. In addition, we have showed that down-regulation of PAX2 by an AT1R antagonist as well as JAK-II and STAT3 inhibitors suppress prostate cancer cell growth. RESULTS Collectively, these findings show for the first time that the renin-angiotensin system (RAS) may promote prostate tumorigenesis via up-regulation of PAX2 expression. CONCLUSIONS Therefore, PAX2 may be a novel therapeutic target for the treatment of carcinomas such as prostate cancer via the down-regulation of its expression by targeting the AT1R signaling pathways.
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Affiliation(s)
- Sudeep K Bose
- Department of Pathology & Lab Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
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Bose SK, Gibson W, Bullard RS, Donald CD. PAX2 oncogene negatively regulates the expression of the host defense peptide human beta defensin-1 in prostate cancer. Mol Immunol 2008; 46:1140-8. [PMID: 19118900 DOI: 10.1016/j.molimm.2008.11.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Revised: 10/27/2008] [Accepted: 11/01/2008] [Indexed: 10/21/2022]
Abstract
Human beta defensin-1 (hBD1) is a component of the immune system which links the innate and adaptive immune responses. We have demonstrated that hBD1 induces rapid cytolysis of prostate cancer cells and that it may also possess tumor suppressive abilities. In addition, there is a high frequency of cancer-specific loss of hBD1 expression which further suggests its potential role in tumor progression. However, the factors responsible for the loss of hBD1 expression are not known. PAX2, a transcriptional regulator normally expressed during early development, has been implicated as an oncogene in carcinomas of the kidney, prostate, breast and ovary. It is known that expression of PAX2 in these tumor cells mediates the evasion of cell death through the suppression of cell death pathways involving the p53 tumor suppressor. However, we have demonstrated that knock-down of PAX2 expression results in cell death independent of p53 status, thus suggesting that additional cell death pathways are negatively regulated by PAX2. Here we describe a novel pathway in which PAX2 represses hBD1 expression through binding of the PAX2 homeodomain to the hBD1 promoter. Furthermore, knock-down of PAX2 expression results in the re-expression of hBD1, and subsequently prostate cancer cell death. These findings are the first to demonstrate that the PAX2 oncogene suppresses hBD1 expression in cancer and further implicate PAX2 as a novel therapeutic target for prostate cancer treatment.
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Affiliation(s)
- Sudeep K Bose
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
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Cooper CR, Graves B, Pruitt F, Chaib H, Lynch JE, Cox AK, Sequeria L, van Golen KL, Evans A, Czymmek K, Bullard RS, Donald CD, Sol-Church K, Gendernalik JD, Weksler B, Farach-Carson MC, Macoska JA, Sikes RA, Pienta KJ. Novel surface expression of reticulocalbin 1 on bone endothelial cells and human prostate cancer cells is regulated by TNF-alpha. J Cell Biochem 2008; 104:2298-309. [PMID: 18561328 DOI: 10.1002/jcb.21785] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
An unbiased cDNA expression phage library derived from bone-marrow endothelial cells was used to identify novel surface adhesion molecules that might participate in metastasis. Herein we report that reticulocalbin 1 (RCN1) is a cell surface-associated protein on both endothelial (EC) and prostate cancer (PCa) cell lines. RCN1 is an H/KDEL protein with six EF-hand, calcium-binding motifs, found in the endoplasmic reticulum. Our data indicate that RCN1 also is expressed on the cell surface of several endothelial cell lines, including human dermal microvascular endothelial cells (HDMVECs), bone marrow endothelial cells (BMEC), and transformed human bone marrow endothelial cells (TrHBMEC). While RCN1 protein levels were highest in lysates from HDMVEC, this difference was not statistically significant compared BMEC and TrHBMEC. Given preferential adhesion of PCa to bone-marrow EC, these data suggest that RCN1 is unlikely to account for the preferential metastasis of PCa to bone. In addition, there was not a statistically significant difference in total RCN1 protein expression among the PCa cell lines. RCN1 also was expressed on the surface of several PCa cell lines, including those of the LNCaP human PCa progression model and the highly metastatic PC-3 cell line. Interestingly, RCN1 expression on the cell surface was upregulated by tumor necrosis factor alpha treatment of bone-marrow endothelial cells. Taken together, we show cell surface localization of RCN1 that has not been described previously for either PCa or BMEC and that the surface expression on BMEC is regulated by pro-inflammatory TNF-alpha.
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Affiliation(s)
- Carlton R Cooper
- Center for Translational Cancer Research and Department of Biological Sciences, University of Delaware, Newark, Delaware 19716, USA.
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Bose SK, Bullard RS, Donald CD. Oncogenic role of engrailed-2 (en-2) in prostate cancer cell growth and survival. Transl Oncogenomics 2008; 3:37-43. [PMID: 21566742 PMCID: PMC3022358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Prostate cancer is the second leading cause of cancer death among men in the United States of America. However, the molecular mechanisms underlying the disease remain largely unknown. Therefore, the identification of tumor specific molecules that serve as targets for the development of new cancer drugs is considered to be a major goal in cancer research. The mouse Engrailed-2 (En-2) gene, which is a homeobox-containing transcription factor was recently identified as a candidate oncogene in breast cancer. Here, we demonstrate that En-2 is over-expressed in human prostate cancer cells as compared to normal prostate epithelial cells. In addition, our data suggests that EN2 expression may be positively modulated by PAX2 transcription factor. Furthermore, down-regulation of EN2 expression by siRNA resulted in a decrease in PAX2 expression. We also provide evidence that down-regulation of EN2 expression causes a dramatic decrease in prostate cancer cell proliferation. Therefore, from our studies we conclude that En-2 is a candidate oncogene in prostate cancer and its PAX2-regulated expression contributes to prostate cancer cell growth.
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Affiliation(s)
| | | | - Carlton D. Donald
- Correspondence: Carlton D. Donald, Ph.D., 165 Ashley Avenue, Suite 309, Charleston, SC-29425. Tel: 843-364-6334; Fax: 843-792-0368;
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Bullard RS, Gibson W, Bose S, Belgrave JK, Eaddy AC, Wright CJ, Hazen-Martin DJ, Lage JM, Keane TE, Ganz TA, Donald CD. Functional analysis of the host defense peptide Human Beta Defensin-1: new insight into its potential role in cancer. Mol Immunol 2007; 45:839-48. [PMID: 17868871 PMCID: PMC2131727 DOI: 10.1016/j.molimm.2006.11.026] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Revised: 11/12/2006] [Accepted: 11/26/2006] [Indexed: 10/22/2022]
Abstract
Although it is known that innate immunity is key for protecting the body against foreign agents such as bacteria, little is known about elements of the innate immune system that have anti-tumor activity. Human Beta Defensin-1 (hBD-1), an important component of the innate immune response, is lost at high frequencies in malignant prostatic tissue, while high levels of expression are maintained in adjacent benign regions. In prostate carcinoma, frequent genetic alterations occur in the 8p22-23 region and several studies indicate there may be multiple tumor suppressor genes present within this region. The high incidence of loss of hBD-1 expression in prostate cancer, along with its chromosomal location of 8p23.2, raised the possibility that it may play a role in tumor suppression. To gain insight as to its function in prostate cancer, hBD-1 was cloned and ectopically expressed in four prostate cancer cell lines. Induction of hBD-1 expression resulted in a decrease in cellular growth in DU145 and PC3 cells. However, hBD-1 has no effect on the growth of androgen receptor (AR) positive LNCaP prostate cancer cells, but was again growth suppressive to PC3 cells with ectopic AR expression (PC3/AR+). hBD-1 also caused rapid induction of cytolysis and caspase-mediated apoptosis in DU145 and PC3 prostate cancer cells. Although the regulation of hBD-1 was not addressed in this study, our preliminary data demonstrated that the pathways involved may include cMYC and PAX2. Data presented here are the first to provide evidence of its potential role in prostate cancer cell death.
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Affiliation(s)
- Rebecca S. Bullard
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Willietta Gibson
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Sudeep Bose
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Jamila K. Belgrave
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Andre C. Eaddy
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Corey J. Wright
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Debra J. Hazen-Martin
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
- Hollings Cancer Center, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Janice M. Lage
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
- Hollings Cancer Center, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Thomas E. Keane
- Department of Urology, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
- Hollings Cancer Center, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
| | - Tomas A. Ganz
- University of California at Los Angeles, UCLA Med-Pul & Critical Care/Med-Hematology & Oncology, BOX 951690, 37-055 CHS, Los Angeles, CA 90095-1690, USA
| | - Carlton D. Donald
- Department of Pathology and Laboratory Medicine, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
- Hollings Cancer Center, 165 Ashley Avenue, PO Box 250620, Charleston, SC 29425, USA
- *Corresponding Author: Carlton D. Donald, PhD, 165 Ashley Avenue, Suite 309, Charleston, SC 29425. E-mail: , Telephone: 843-792-1459, Fax: 843-792-0368
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Gibson W, Green A, Bullard RS, Eaddy AC, Donald CD. Inhibition of PAX2 expression results in alternate cell death pathways in prostate cancer cells differing in p53 status. Cancer Lett 2006; 248:251-61. [PMID: 16996682 DOI: 10.1016/j.canlet.2006.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2006] [Revised: 07/19/2006] [Accepted: 08/01/2006] [Indexed: 01/19/2023]
Abstract
Inhibition of apoptosis is a critical pathophysiological factor that contributes to the development of prostate cancer. Recently, PAX2, a transcriptional regulator implicated in oncogenesis, has been demonstrated to be expressed by prostate cancer. However, its downstream molecular pathways for suppression of apoptosis, other than the tumor suppressor gene p53, have yet to be elucidated. Here, we examine the effects of inhibiting PAX2 expression by prostate cancer cells that differ in p53 gene status. These data collectively demonstrate that PAX2 inhibition results in cell death independent of p53, and that additional tumor suppressors or cell death pathways may be inhibited by PAX2 in prostate cancer cells.
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Affiliation(s)
- Willietta Gibson
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Suite 309, Charleston, SC 29425, USA
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7
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Donald CD, Sun CQ, Lim SD, Macoska J, Cohen C, Amin MB, Young AN, Ganz TA, Marshall FF, Petros JA. Cancer-specific loss of beta-defensin 1 in renal and prostatic carcinomas. J Transl Med 2003; 83:501-5. [PMID: 12695553 DOI: 10.1097/01.lab.0000063929.61760.f6] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
In a previous large-scale gene expression profiling study of renal epithelial neoplasms, human beta-defensin-1 (DEFB1) was found to be significantly down-regulated in conventional clear cell (renal) carcinoma. We have now completed an expanded expression analysis of this gene. We performed immunohistochemical analysis for the DEFB1 protein in clinical specimens of both renal cell carcinoma and prostate cancer. In a subset of prostate cancers, we performed laser capture microdissection and RT-PCR to correlate mRNA levels with protein levels. Overall, 82% of prostate cancers exhibit either complete loss of protein expression or only minimal expression, whereas the adjacent benign epithelium retained expression in all cases. Similarly, 90% of renal cell carcinomas show cancer-specific loss of DEFB1 protein. In the prostate cancer subset analysis, mRNA levels correlate with protein levels. We have thus demonstrated the cancer-specific down-regulation of DEFB1 in a large sample of prostatic and renal carcinomas and validated one of the key findings of previous cancer gene profiling studies of prostatic and renal neoplasia.
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Affiliation(s)
- Carlton D Donald
- Department of Urology, Emory University School of Medicine, Atlanta, Georgia, USA
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Donald CD, Laddu A, Chandham P, Lim SD, Cohen C, Amin M, Gerton GL, Marshall FF, Petros JA. Expression of progranulin and the epithelin/granulin precursor acrogranin correlates with neoplastic state in renal epithelium. Anticancer Res 2001; 21:3739-42. [PMID: 11911241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
BACKGROUND Current traditional pathological parameters, including staging and grading, are not sufficient in predicting outcome in patients with renal cell carcinoma (RCC). Acrogranin is an epithelial growth factor and has been demonstrated to play a role in teratocarcinogenesis and tumorigenesis. The aim of this study was to examine levels of acrogranin in renal cancer. MATERIALS AND METHODS Western blot analysis was performed on renal tissue protein lysates. In addition, immunohistochemical (IHC) analysis of acrogranin expression was conducted on tissue sections of various histological types and grades of RCC. RESULTS Western analysis showed that acrogranin levels were low in benign renal tissue and increased in malignant renal tissue. In addition, IHC revealed that high-grade RCC exhibited higher levels of expression than low-grade RCC and normal tissue. CONCLUSION These data suggest that acrogranin may be a functional important growth factor in RCC and may be a potential molecular marker for high-grade RCC.
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Affiliation(s)
- C D Donald
- Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA
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9
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Donald CD, Cooper CR, Harris-Hooker S, Emmett N, Scanlon M, Cooke DB. Cytoskeletal organization and cell motility correlates with metastatic potential and state of differentiation in prostate cancer. Cell Mol Biol (Noisy-le-grand) 2001; 47:1033-8. [PMID: 11785653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The actin cytoskeleton is the key cellular machinery responsible for cellular movement. Changes in the organization and distribution of actin and actin binding protein are necessary for several cellular processes such as focal adhesion formation, cell motility and cell invasion. Here we examined differences in cytoskeletal protein distribution, cell morphometry and cell motility of metastatic and non-metastatic cells. Correlations were found between metastatic potential phenotypic properties such as cell motility, cell spreading and cytoskeletal organization in prostate cancer. As a cell progresses from a normal state to a malignant state, it loses its ability to function normally and also become poorly differentiated. Differentiation therapy is concerned with the redirection of malignant cells toward a terminal, non-dividing state using non-cytotoxic agents. Two well acknowledged differentiation agents, retinoic acid (RA) and diflouromethylomithine (DFMO) were examined for their ability to alter cellular phenotypes associated with metastatic potential in rat prostate cancer cell lines. The results of these studies indicate that there are sub-cellular differences between non-metastatic and highly metastatic cells relative to cytoskeletal organization. We also show that treatment of highly metastatic cells with either RA or DFMO significantly alters cell morphology, cell morphometry and motility to states similar to non-metastatic cells.
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Affiliation(s)
- C D Donald
- Department of Biological Sciences, Clark Atlanta University, GA 30314, USA
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10
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Abstract
One of the hallmarks of ionizing radiation exposure is the formation of clustered damage that includes closely opposed lesions. We show that the Ku70/80 complex (Ku) has a role in the repair of closely opposed lesions in DNA. DNA containing a dihydrouracil (DHU) close to an opposing single strand break was used as a model substrate. It was found that Ku has no effect on the enzymatic activity of human endonuclease III when the substrate DNA contains only DHU. However, with DNA containing a DHU that is closely opposed to a single strand break, Ku inhibited the nicking activity of human endonuclease III as well as the amount of free double strand breaks induced by the enzyme. The inhibition on the formation of a free double strand break by Ku was found to be much greater than the inhibition of human endonuclease III-nicking activity by Ku. Furthermore, there was a concomitant increase in the formation of Ku-DNA complexes when endonuclease III was present. Similar results were also observed with Escherichia coli endonuclease III. These results suggest that Ku reduces the formation of endonuclease III-induced free double strand breaks by sequestering the double strand breaks formed as a Ku-DNA complex. In doing so, Ku helps to avoid the formation of the intermediary free double strand breaks, possibly helping to reduce the mutagenic event that might result from the misjoining of frank double strand breaks.
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Affiliation(s)
- M Hashimoto
- Department of Radiation Oncology, Emory University, Atlanta, Georgia 30335, USA
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Venkhataraman R, Donald CD, Roy R, You HJ, Doetsch PW, Kow YW. Enzymatic processing of DNA containing tandem dihydrouracil by endonucleases III and VIII. Nucleic Acids Res 2001; 29:407-14. [PMID: 11139610 PMCID: PMC29670 DOI: 10.1093/nar/29.2.407] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2000] [Revised: 11/16/2000] [Accepted: 11/16/2000] [Indexed: 11/13/2022] Open
Abstract
Endonuclease III from Escherichia coli, yeast (yNtg1p and yNtg2p) and human and E.coli endonuclease VIII have a wide substrate specificity, and recognize oxidation products of both thymine and cytosine. DNA containing single dihydrouracil (DHU) and tandem DHU lesions were used as substrates for these repair enzymes. It was found that yNtg1p prefers DHU/G and exhibits much weaker enzymatic activity towards DNA containing a DHU/A pair. However, yNtg2p, E. coli and human endonuclease III and E.coli endonuclease VIII activities were much less sensitive to the base opposite the lesion. Although these enzymes efficiently recognize single DHU lesions, they have limited capacity for completely removing this damaged base when DHU is present on duplex DNA as a tandem pair. Both E.coli endonuclease III and yeast yNtg1p are able to remove only one DHU in DNA containing tandem lesions, leaving behind a single DHU at either the 3'- or 5'-terminus of the cleaved fragment. On the other hand, yeast yNtg2p can remove DHU remaining on the 5'-terminus of the 3' cleaved fragment, but is unable to remove DHU remaining on the 3'-terminus of the cleaved 5' fragment. In contrast, both human endonuclease III and E.coli endonuclease VIII can remove DHU remaining on the 3'-terminus of a cleaved 5' fragment, but are unable to remove DHU remaining on the 5'-terminus of a cleaved 3' fragment. Tandem lesions are known to be generated by ionizing radiation and agents that generate reactive oxygen species. The fact that these repair glycosylases have only a limited ability to remove the DHU remaining at the terminus suggests that participation of other repair enzymes is required for the complete removal of tandem lesions before repair synthesis can be efficiently performed by DNA polymerase.
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Affiliation(s)
- R Venkhataraman
- Department of Radiation Oncology and Department of Biochemistry, Emory University School of Medicine, 145 Edgewood Avenue, Atlanta, GA 30335, USA
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Conway KE, McConnell BB, Bowring CE, Donald CD, Warren ST, Vertino PM. TMS1, a novel proapoptotic caspase recruitment domain protein, is a target of methylation-induced gene silencing in human breast cancers. Cancer Res 2000; 60:6236-42. [PMID: 11103776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Gene silencing associated with aberrant methylation of promoter region CpG islands is an acquired epigenetic alteration that serves as an alternative to genetic defects in the inactivation of tumor suppressor and other genes in human cancers. The hypothesis that aberrant methylation plays a direct causal role in carcinogenesis hinges on the question of whether aberrant methylation is sufficient to drive gene silencing. To identify downstream targets of methylation-induced gene silencing, we used a human cell model in which aberrant CpG island methylation is induced by ectopic expression of DNA methyltransferase. Here we report the isolation and characterization of TMS1 (target of methylation-induced silencing), a novel CpG island-associated gene that becomes hypermethylated and silenced in cells overexpressing DNA cytosine-5-methyltransferase-1. We also show that TMS1 is aberrantly methylated and silenced in human breast cancer cells. Forty percent (11 of 27) of primary breast tumors exhibited aberrant methylation of TMS1. TMS1 is localized to chromosome 16p11.2-12.1 and encodes a 22-kDa predicted protein containing a COOH-terminal caspase recruitment domain, a recently described protein interaction motif found in apoptotic signaling molecules. Ectopic expression of TMS1 induced apoptosis in 293 cells and inhibited the survival of human breast cancer cells. The data suggest that methylation-mediated silencing of TMS1 confers a survival advantage by allowing cells to escape from apoptosis, supporting a new role for aberrant methylation in breast tumorigenesis.
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Affiliation(s)
- K E Conway
- Department of Radiation Oncology and the Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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Donald CD, Montgomery DE, Emmett N, Cooke DB. Invasive potential and substrate dependence of attachment in the dunning R-3327 rat prostate adenocarcinoma model. Invasion Metastasis 2000; 18:165-75. [PMID: 10640902 DOI: 10.1159/000024509] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cancer cell attachment to and invasion of the extracellular matrix has been associated with the metastatic potential of cell lines of the Dunning R-3327 rat prostatic adenocarcinoma model. We investigated the cell-matrix interactions of prostate tumor cells by comparing the invasive ability through reconstructed extracellular matrix and attachment upon EHS NATRIX (natural extracellular matrix), fibronectin, laminin, and collagen Type IV. We observed a correlation between metastatic potential and substrate dependence of attachment in prostate cancer cells. Nonmetastatic AT-1 cells possessed a higher adhesive potential to extracellular matrix components than the highly metastatic cells (ML, MLL and AT-3). It was also found that the invasive potential of the three highly metastatic cell lines was significantly higher than that of the nonmetastatic cell line. Here, it is reported that the ability to traverse a matrigel matrix correlates with their metastatic potential. These observations suggest that the extracellular matrix components are highly involved in influencing prostate cancer cell activities. In addition, we investigated the effects of two differentiation agents, retinoic acid (RA) and difluoromethylornithine (DFMO), on the adhesive and invasive profiles of the tumor cells. After treatment with both agents, adhesion was increased to levels not different from nonmetastatic cells. Furthermore, the ability of highly metastatic cells to traverse a matrigel barrier was significantly reduced after treatment with both differentiation agents. These results suggest that RA and DFMO are capable in reversing the metastatic potential of prostate cancer cells in vitro and may give a possible insight into their role as potential therapeutic agents in vivo.
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Affiliation(s)
- C D Donald
- Department of Biological Sciences, Clark Atlanta University, Atlanta, GA, USA
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