Survivin and inducible nitric oxide synthase production during 4NQO-induced rat tongue carcinogenesis: A possible relationship

• Published in: Experimental and molecular pathology 2007-08, Vol.83 (1), p.131-137
• Main Authors: Ribeiro, Daniel Araki, Kitakawa, Darcio, Domingues, Maria Aparecida Custodio, Cabral, Luiz Antonio Guimarães, Marques, Mariângela Esther Alencar, Salvadori, Daisy Maria Favero
• Format: Article
• Language: English
• Subjects: 4-Nitroquinoline 1-oxide; 4-Nitroquinoline-1-oxide - pharmacology; Animals; Biological and medical sciences; Cell Transformation, Neoplastic - drug effects; Cell Transformation, Neoplastic - metabolism; Cell Transformation, Neoplastic - pathology; Immunohistochemistry; Investigative techniques, diagnostic techniques (general aspects); Male; Malignant transformation; Medical sciences; Microtubule-Associated Proteins - biosynthesis; Nitric oxide; Nitric Oxide Synthase Type II - biosynthesis; Oral squamous cell carcinoma; Otorhinolaryngology. Stomatology; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Rat tongue mucosa; Rats; Rats, Wistar; Survivin; Tongue Neoplasms - chemically induced; Tongue Neoplasms - metabolism; Tongue Neoplasms - pathology; Tumors; Upper respiratory tract, upper alimentary tract, paranasal sinuses, salivary glands: diseases, semeiology
• ISSN: 0014-4800; 1096-0945
• DOI: 10.1016/j.yexmp.2007.02.006

This study was undertaken to investigate, by immunohistochemistry, the expression of survivin and inducible nitric oxide synthase during 4NQO-induced rat tongue carcinogenesis. Male Wistar rats were distributed into three groups of 10 animals each and treated with 50 ppm 4NQO solution through their drinking water for 4, 12, and 20 weeks. Ten animals were used as negative control. Although no histopathological abnormalities were induced in the epithelium after 4 weeks of carcinogen exposure, survivin and iNOS were expresssed ( p < 0.05) in some cells of the ‘normal’ oral epithelium. In pre-neoplastic lesions at 12 weeks following carcinogen exposure, the levels of survivin and iNOS were increased ( p < 0.05) when compared to negative control, being the strongest effect observed to iNOS. In well-differentiated squamous cell carcinoma induced after 20 weeks of treatment with 4NQO, survivin and iNOS were expressed in some tumor cells. Lack of immunoreactivity for both markers was observed in the negative control group. Taken together, our results support the belief that expression of survivin and iNOS are early events during malignant transformation and conversion of the oral mucosa.