Radiation used for head and neck cancer increases virulence in Candida tropicalis isolated from a cancer patient.
BMC Infect Dis
; 17(1): 783, 2017 12 20.
Article
en En
| MEDLINE
| ID: mdl-29262785
BACKGROUND: Studies have shown that radiation from radiotherapy increases the yeast colonization of patients. However it is not clear, if such radiation alters the yeast itself. The aim of the present study was therefore to report the direct impact of gamma radiation on Candida tropicalis. METHODS: C. tropicalis was obtained from a patient with a carcinoma, a suspension of this yeast containing 2.0 × 103 colony forming units per milliliter was prepared. It was submitted to gamma radiation dosage similar to that used in the treatment of head and neck cancer. After a cumulative dose of 7200 cGy some virulence attributes of C. tropicalis, including macro and micromorphological characteristics, adhesion and biofilm abilities, murine experimental infection and phagocytosis resistance were evaluated on irradiated and non-irradiated yeasts. RESULTS: After irradiation the colony morphology of the yeast was altered from a ring format to a smooth appearance in most colonies. Scanning electron microscopy revealed notable differences in the structures of both these colonies and the yeast cells, with the loss of pseudohyphae following irradiation and an increase in extracellular matrix production. The adherence and biofilm production of the yeast was greater following irradiation, both in terms of the number of yeasts and total biomass production on several abiotic surfaces and TR146 cells. The phagocytic index of the irradiated yeasts was not statistically different; however, the presence of cellular debris was detected in the kidneys of infected animals. Mice infected with irradiated yeasts developed an infection at the site of the yeast inoculation, although systemic infection was unchanged. CONCLUSIONS: Our findings show for the first time that C. tropicalis, one of the most important yeasts from colonization, which cause fatal candidemia in cancer patients, is affected by gamma irradiation, with changes to its virulence profile.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Radioterapia
/
Virulencia
/
Candida tropicalis
/
Candidiasis Invasiva
/
Neoplasias de Cabeza y Cuello
Límite:
Humans
Idioma:
En
Revista:
BMC Infect Dis
Asunto de la revista:
DOENCAS TRANSMISSIVEIS
Año:
2017
Tipo del documento:
Article
País de afiliación:
Brasil
Pais de publicación:
Reino Unido