Clinically relevant radioresistant cells exhibit resistance to H2O2 by decreasing internal H2O2 and lipid peroxidation.
Tumour Biol
; 40(9): 1010428318799250, 2018 Sep.
Article
em En
| MEDLINE
| ID: mdl-30192208
ABSTRACT
Radiation therapy is one of the choices to treat malignant tumors. In radiation therapy, existence of radiation-resistant cell is a major problem to overcome. We established clinically relevant radioresistant cells that had been obtained by exposing to 2 Gy/day X-rays for more than 30 days. These cells are resistant to 2 Gy/day X-ray exposure and anticancer agents. However, the underlying resistance mechanism remains unclear. We investigated the resistance of clinically relevant radioresistant cells to hydrogen peroxide (H2O2), confirming a degree of resistance. Neither catalase enzyme activity nor aquaporins appeared to be involved in H2O2 resistance. Mitochondrial DNA copy number, adenosine triphosphate (ATP) concentration, and plasma membrane potential were decreased. The timing of H2O2 intake was delayed and lipid peroxidation was decreased. Sensitivity of clinically relevant radioresistant cells to H2O2 was enhanced by 1-palmitoyl-2-(5'-oxo-valeroyl)-sn-glycero-3-phosphocholine administration. These results suggest that the membrane status is a major factor conferring H2O2 resistance in clinically relevant radioresistant cells, and we should further investigate how membrane status could be used to enhance the therapeutic effect on cancer.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tolerância a Radiação
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Neoplasias Bucais
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Carcinoma de Células Escamosas
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Peroxidação de Lipídeos
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Oxidantes
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Peróxido de Hidrogênio
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Antineoplásicos
Limite:
Humans
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article