| First Author | Vorce RL | Year | 1991 |
| Journal | J Toxicol Environ Health | Volume | 34 |
| Issue | 3 | Pages | 385-95 |
| PubMed ID | 1942124 | Mgi Jnum | J:650 |
| Mgi Id | MGI:49186 | Doi | 10.1080/15287399109531575 |
| Citation | Vorce RL, et al. (1991) Differential DNase I hypersensitivity of ras oncogenes in B6C3F1, C3H/He, and C57BL/6 mouse liver. J Toxicol Environ Health 34(3):385-95 |
| abstractText | The male hybrid B6C3F1 mouse exhibits a 30% spontaneous hepatoma incidence, whereas the paternal C3H/He strain and the maternal C57BL/6 strain exhibit a 60% and a negligible incidence, respectively. In addition, both male and female B6C3F1 mice are extremely sensitive to chemical induction of hepatocarcinogenesis. The Ha-ras, Ki-ras, and myc oncogenes have been implicated in a variety of solid tumors. Specifically, Ha- and, less frequently, Ki-ras have been reported to be activated in B6C3F1 mouse liver tumors. The objective of this study was to examine a possible point of transcriptional control of Ha-ras, Ki-ras, and myc in all three mouse strains, our hypothesis being that these oncogenes may be primed for expression in the nascent liver of those strains exhibiting a high spontaneous hepatoma incidence. A positive correlation has been established between gene expression and the presence of DNase I hypersensitive sites. DNase I hypersensitive sites were observed in the Ha-ras and myc oncogenes in the three mouse strains. However, Ha-ras appears to possess an additional site in B6C3F1 and C3H/He as compared to C57BL/6. Similarly, the Ki-ras oncogene exhibited a DNase I hypersensitive site only in B6C3F1 and C3H/He mouse liver. These results indicate that the hepatoma-prone strains (B6C3F1 and C3H/He) may have a greater potential for Ha- and Ki-ras expression than does the non-hepatoma-prone strain (C57BL/6). |
