| 1423854 |
Rumsby PC, Evans JG, Phillimore HE, Carthew P, Smith AG: Search for Ha-ras codon 61 mutations in liver tumours caused by hexachlorobenzene and Aroclor 1254 in C57BL/10ScSn mice with iron overload. Carcinogenesis. 1992 Oct;13(10):1917-20.
C57BL/10ScSn mice administered iron--dextran and fed the environmental pollutants hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) develop hepatic nodules and carcinomas within 18 months. A range of lesions from the livers were analysed for the presence of mutations in the Ha-ras proto-oncogene at codon 61 using the polymerase chain reaction to amplify DNA from formalin-fixed sections, followed by oligonucleotide hybridization. Only two mutations from 23 preneoplastic and neoplastic lesions induced by HCB were detected (a focus of altered cells and a trabecular cell carcinoma). With Aroclor 1254 no mutations were detected in 28 areas at various stages of carcinogenesis analysed. Sequencing of the two mutations generated by HCB showed a C--> T transversion at the first base of codon 61 (carcinoma) and an A--> T transversion at the second base (proliferative focus). Thus, in marked contrast to some other systems of mouse liver tumour induction, hepatocarcinogenesis caused by HCB and PCBs in C57BL/10ScSn mice is an example of carcinogenesis which does not involve a high frequency of Ha-ras gene mutation at codon 61. |
7(0,0,1,2) |