Cytokeratin 19 gene expression of the carcinogenesis process in tongue carcinoma of the mouse induced by 4-nitroquinoline 1-oxide

Abstract

The cytokeratin 19 (CK 19) gene tends to reflect the degree of tumor differentiation. We used the reverse transcription polymerase chain reaction (RT-PCR) and Northern blotting to investigate the expression of the CK 19 gene during carcinogenesis of the mouse tongue induced by 4-nitroquinoline-1-oxide (4 NQO). We also examined the influence of 4 NQO on the mouse tongue with the specific objective of determining the carcinogenicity of that substance in this model system. In addition, we analyzed MMP3 and ETS-1 using RT-PCR and immunohistochemisty. CK 19 mRNA was expressed weakly in normal epithelium, moderately in dysplasia, and strongly in verrucous carcinoma. However CK 19 mRNA expression was weak in the invasive carcinoma. These results indicate that the CK 19 gene is more actively transcripted in epithelial dysplasia and cancer cells than in normal epithelial cells. Futhermore, CK 19 is an important determinant of cell conformation. Its overexpression in oral SCCs decreases their invasive potential by diminishing migratory capability. Shika Igaku (J Osaka Odontol Soc) 2003 Mar; 66(1): 72-79.