Abstract
Novel approaches to cancer gene therapy currently exploit tumour hypoxia to achieve transcriptional targeting using oxygen-regulated enhancer elements called hypoxia response elements. The activity of such elements in hypoxic cells is directly dependent on upregulation of the hypoxia-inducible transcription factor-1 However tumours also contain areas of anoxia, which may be considered a more tumour-selective transcriptional stimulus than hypoxia for targeting gene therapy to tumours. Another element, from the rat virus-like retrotransposon, VL30 (termed the "secondary anoxia response element") has been reported to be more highly inducible in rat fibroblasts under anoxia than hypoxia. To investigate anoxia as a potential transcriptional target in human tumours, we have examined secondary anoxia response element inducibility in two human breast cancer cell lines, MCF-7 and T47D, under anoxia, hypoxia and normoxia. In both cell types, the trimerised secondary anoxia response element showed greater inducibility in anoxia than hypoxia (1% and 0.5% O(2)). The anoxic response of the secondary anoxia response element was shown to be dependent on hypoxia-inducible transcription factor-1 and the presence of a hypoxia-inducible transcription binding site consensus (5'-ACGTG-3'). Mutational analysis demonstrated that the base immediately 5' to this modulates the anoxic/hypoxic induction of the secondary anoxia response element, such that TACGTG>GACGTG>CACGTG. A similar correlation was found for erythropoietin, phosphoglycerate kinase 1, and aldolase hypoxia response elements, which contain these respective 5' flanking bases.
| Original language | English |
|---|---|
| Pages (from-to) | 1173-1181 |
| Number of pages | 9 |
| Journal | British Journal of Cancer |
| Volume | 87 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 4 Nov 2002 |
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Keywords
- Animals
- Breast Neoplasms/genetics
- CHO Cells
- Cell Hypoxia
- Cricetinae
- DNA-Binding Proteins/analysis
- Erythropoietin/pharmacology
- Female
- Genetic Therapy
- Humans
- Hypoxia-Inducible Factor 1
- Hypoxia-Inducible Factor 1, alpha Subunit
- Nuclear Proteins/analysis
- Oxygen/pharmacology
- Rats
- Response Elements/physiology
- Retroelements
- Transcription Factors
- Tumor Cells, Cultured
Cite this
Regulation of a rat VL30 element in human breast cancer cells in hypoxia and anoxia : role of HIF-1. / Ameri, K; Burke, B; Lewis, C E; Harris, A L.
In: British Journal of Cancer, Vol. 87, No. 10, 04.11.2002, p. 1173-1181.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Regulation of a rat VL30 element in human breast cancer cells in hypoxia and anoxia
T2 - role of HIF-1
AU - Ameri, K
AU - Burke, B
AU - Lewis, C E
AU - Harris, A L
N1 - Copyright 2002 Cancer Research UK
PY - 2002/11/4
Y1 - 2002/11/4
N2 - Novel approaches to cancer gene therapy currently exploit tumour hypoxia to achieve transcriptional targeting using oxygen-regulated enhancer elements called hypoxia response elements. The activity of such elements in hypoxic cells is directly dependent on upregulation of the hypoxia-inducible transcription factor-1 However tumours also contain areas of anoxia, which may be considered a more tumour-selective transcriptional stimulus than hypoxia for targeting gene therapy to tumours. Another element, from the rat virus-like retrotransposon, VL30 (termed the "secondary anoxia response element") has been reported to be more highly inducible in rat fibroblasts under anoxia than hypoxia. To investigate anoxia as a potential transcriptional target in human tumours, we have examined secondary anoxia response element inducibility in two human breast cancer cell lines, MCF-7 and T47D, under anoxia, hypoxia and normoxia. In both cell types, the trimerised secondary anoxia response element showed greater inducibility in anoxia than hypoxia (1% and 0.5% O(2)). The anoxic response of the secondary anoxia response element was shown to be dependent on hypoxia-inducible transcription factor-1 and the presence of a hypoxia-inducible transcription binding site consensus (5'-ACGTG-3'). Mutational analysis demonstrated that the base immediately 5' to this modulates the anoxic/hypoxic induction of the secondary anoxia response element, such that TACGTG>GACGTG>CACGTG. A similar correlation was found for erythropoietin, phosphoglycerate kinase 1, and aldolase hypoxia response elements, which contain these respective 5' flanking bases.
AB - Novel approaches to cancer gene therapy currently exploit tumour hypoxia to achieve transcriptional targeting using oxygen-regulated enhancer elements called hypoxia response elements. The activity of such elements in hypoxic cells is directly dependent on upregulation of the hypoxia-inducible transcription factor-1 However tumours also contain areas of anoxia, which may be considered a more tumour-selective transcriptional stimulus than hypoxia for targeting gene therapy to tumours. Another element, from the rat virus-like retrotransposon, VL30 (termed the "secondary anoxia response element") has been reported to be more highly inducible in rat fibroblasts under anoxia than hypoxia. To investigate anoxia as a potential transcriptional target in human tumours, we have examined secondary anoxia response element inducibility in two human breast cancer cell lines, MCF-7 and T47D, under anoxia, hypoxia and normoxia. In both cell types, the trimerised secondary anoxia response element showed greater inducibility in anoxia than hypoxia (1% and 0.5% O(2)). The anoxic response of the secondary anoxia response element was shown to be dependent on hypoxia-inducible transcription factor-1 and the presence of a hypoxia-inducible transcription binding site consensus (5'-ACGTG-3'). Mutational analysis demonstrated that the base immediately 5' to this modulates the anoxic/hypoxic induction of the secondary anoxia response element, such that TACGTG>GACGTG>CACGTG. A similar correlation was found for erythropoietin, phosphoglycerate kinase 1, and aldolase hypoxia response elements, which contain these respective 5' flanking bases.
KW - Animals
KW - Breast Neoplasms/genetics
KW - CHO Cells
KW - Cell Hypoxia
KW - Cricetinae
KW - DNA-Binding Proteins/analysis
KW - Erythropoietin/pharmacology
KW - Female
KW - Genetic Therapy
KW - Humans
KW - Hypoxia-Inducible Factor 1
KW - Hypoxia-Inducible Factor 1, alpha Subunit
KW - Nuclear Proteins/analysis
KW - Oxygen/pharmacology
KW - Rats
KW - Response Elements/physiology
KW - Retroelements
KW - Transcription Factors
KW - Tumor Cells, Cultured
U2 - 10.1038/sj.bjc.6600576
DO - 10.1038/sj.bjc.6600576
M3 - Article
VL - 87
SP - 1173
EP - 1181
JO - British Journal of Cancer
JF - British Journal of Cancer
SN - 0007-0920
IS - 10
ER -