The influence of sleep deprivation on expression of apoptosis regulatory proteins p53, bcl-2 and bax following rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide.
BACKGROUND
The aim of this study was to evaluate whether paradoxical sleep deprivation could affects the mechanisms and pathways essentials for cancer cells in tongue cancer induced by 4-nitroquinole 1-oxide in Wistar rats.


METHODS
For this purpose, the animals were distributed into 4 groups of 5 animals each treated with 50 ppm 4 nitroquinoline 1 oxide (4 NQO) solution through their drinking water for 4 and 12 weeks. The animals were submitted to paradoxical sleep deprivation (PSD) for 72 h using the modified multiple platform method, which consisted of placing 5 mice in a cage (41 × 34 × 16 cm) containing 10 circular platforms (3.5 cm in diameter) with water 1 cm below the upper surface. The investigations were conducted using immunohistochemistry of p53, Bax and Bcl-2 proteins related to apoptosis and its pathways. Statistical analysis was performed by Kruskal-Wallis non-parametric test followed by the Dunn's test using SPSS software pack (version 1.0). P value < 0.05 was considered for statistic significance.


RESULTS
Although no histopathological abnormalities were induced in the epithelium after 4 weeks of carcinogen exposure in all groups, in 12 weeks were observed pre-neoplasic lesions. Data analysis revealed statistically significant differences (P < 0.05) in 4 weeks group for p53 and for bcl-2 and for all immunomarkers after 12 weeks of 4NQO administration.


CONCLUSIONS
Our results reveal that sleep deprivation exerted alterations in proteins associated with proliferation and apoptosis in carcinogenesis.
Department of Pathology, Federal University of São Paulo, UNIFESP, SP, Brazil.
Juliana
J
Noguti
Tathiana Aparecida
TA
Alvarenga
Mônica Levy
ML
Andersen
Sergio
S
Tufik
Celina Tijuko Fujiyama
CT
Oshima
Daniel Araki
DA
Ribeiro
Apoptosis; carcinogenesis; rat; sleep deprivation