Characterization of Chemically Induced Ovarian Carcinomas in an Ethanol-Preferring Rat Model: Influence of Long-Term Melatonin Treatment

Autor(es)

Chuffa, Luiz Gustavo A. ^[1] ; Fioruci-Fontanelli, Beatriz A. ^{[1, 2]} ; Mendes, Leonardo O. ^{[1, 2]} ; Favaro, Wagner J. ^[3] ; Pinheiro, Patricia Fernanda F. ^[1] ; Martinez, Marcelo ^[4] ; Martinez, Francisco Eduardo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista, UNESP, Inst Biociencias, Dept Anat, Botucatu, SP - Brazil

^[2] Univ Estadual Campinas, UNICAMP, Inst Biol, Programa Posgrad Biol Celular & Estrutural, Campinas, SP - Brazil

^[3] Univ Estadual Campinas, UNICAMP, Dept Anat Biol Celular & Fisiol & Biofis, Campinas, SP - Brazil

^[4] UFSCar Univ Fed Sao Carlos, Dept Morfol & Patol, Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 8, n. 12 DEC 18 2013.
• Citações Web of Science: 24

Resumo

Ovarian cancer is the fourth most common cause of cancer deaths among women, and chronic alcoholism may exert co-carcinogenic effects. Because melatonin (mel) has oncostatic properties, we aimed to investigate and characterize the chemical induction of ovarian tumors in a model of ethanol-preferring rats and to verify the influence of mel treatment on the overall features of these tumors. After rats were selected to receive ethanol (EtOH), they were surgically injected with 100 mu g of 7,12-dimethyl-benz{[}a] anthracene (DMBA) plus sesame oil directly under the left ovarian bursa. At 260 days old, half of the animals received i.p. injections of 200 mu g mel/100 g b.w. for 60 days. Four experimental groups were established: Group C, rats bearing ovarian carcinomas (OC); Group C+EtOH, rats voluntarily consuming 10% (v/v) EtOH and bearing OC; Group C+M, rats bearing OC and receiving mel; and Group C+EtOH+M, rats with OC consuming EtOH and receiving mel. Estrous cycle and nutritional parameters were evaluated, and anatomopathological analyses of the ovarian tumors were conducted. The incidence of ovarian tumors was higher in EtOH drinking animals 120 days post-DMBA administration, and mel efficiently reduced the prevalence of some aggressive tumors. Although mel promoted high EtOH consumption, it was effective in synchronizing the estrous cycle and reducing ovarian tumor mass by 20%. While rats in the C group displayed cysts containing serous fluid, C+EtOH rats showed solid tumor masses. After mel treatment, the ovaries of these rats presented as soft and mobile tissues. EtOH consumption increased the incidence of serous papillary carcinomas and sarcomas but not clear cell carcinomas. In contrast, mel reduced the incidence of sarcomas, endometrioid carcinomas and cystic teratomas. Combination of DMBA with EtOH intake potentiated the incidence of OC with malignant histologic subtypes. We concluded that mel reduces ovarian masses and the incidence of adenocarcinomas in ethanol-deprived rats. (AU)

• Processo FAPESP: 11/19294-9 - Indução tumoral ovariana e influência da melatonina sobre o processo inflamatório via sinalização mediada pelo receptor Toll-like 4 em ratas UChB
• Beneficiário: Luiz Gustavo de Almeida Chuffa
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/02466-7 - Indução tumoral ovariana e influência da melatonina sobre o processo inflamatório via sinalização mediada pelo receptor Toll-like 4 em ratas UChB
• Beneficiário: Luiz Gustavo de Almeida Chuffa
• Modalidade de apoio: Auxílio à Pesquisa - Regular