Activating mutations of the c-Ha-ras protooncogene in chemically induced hepatomas of the male B6C3 F1 mouse.
Activating mutations of the c-Ha-ras protooncogene in chemically induced hepatomas of the male B6C3 F1 mouse.
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DOI：
10.1073/pnas.83.16.5825
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发表时间：
1986-08
影响因子：
11.1
通讯作者：
R. Wiseman;S. Stowers;E. Miller;M. Anderson;J. Miller
中科院分区：
文献类型：
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作者：
R. Wiseman;S. Stowers;E. Miller;M. Anderson;J. Miller
活化的c-Ha-ras原癌基因最近在2岁B6C3 F1小鼠的一些自发性肝肿瘤的DNA中被发现。在12日龄雄性B6C3 F1小鼠中，单剂量致癌物引起的高分化肝癌DNA中，c-Ha-ras的激活已被证实。用n -羟基-2-乙酰氨基芴、氨基甲酸乙酯或1'-羟基-2',3'-脱氢雌酮醇诱导25个肝癌的DNA，在NIH 3T3转染试验中含有转化活性。对来自24例肝癌的DNA转化的NIH 3T3细胞进行Southern分析，发现扩增和/或后排限制性内切片段与Ha-ras探针同源。另一个肿瘤含有活化的Ki-ras基因。免疫沉淀和NaDodSO4/PAGE分析来自大多数肝癌的NIH 3T3转化子的p21 ras蛋白表明，激活突变定位在c-Ha-ras基因的第61密码子上。在原发性肿瘤和NIH 3T3细胞的DNA中，通过AT----TA在密码子61的第二个位置上的转化，发现了一个新的Xba I限制位点。这些细胞由氨基甲酸乙酯- 7中的6个和10 1'-羟基-2',3'-脱氢雌二醇诱导的肝癌的DNA转化。选择性寡核苷酸杂交显示，来自7个n -羟基-2-乙酰氨基芴诱导的肝癌的NIH 3T3转化子在第61密码子的第一个位置有CG----AT翻转。根据同样的标准，密码子61第二位置的AT----GC转变是7个氨基甲酸乙酯-中的1个和10个1'-羟基-2',3'-脱氢雌二醇诱导肿瘤中的5个的激活突变。因此，c-Ha-ras激活显然是B6C3 F1小鼠肝癌发生的早期事件，是体内终极化学致癌物与该基因直接反应的结果。
Activated c-Ha-ras protooncogenes have recently been identified in the DNA of some spontaneous hepatic tumors found in 2-year-old B6C3 F1 mice. Activation of c-Ha-ras has now been demonstrated in DNA from well-differentiated hepatomas initiated by a single dose of carcinogen given to male B6C3 F1 mice at 12 days of age. DNA from each of 25 hepatomas, induced by N-hydroxy-2-acetylaminofluorene, vinyl carbamate, or 1'-hydroxy-2',3'-dehydroestragole, containing transforming activity in the NIH 3T3 transfection assay. Southern analysis of NIH 3T3 cells transformed by DNA from 24 of these hepatomas revealed amplified and/or rear-ranged restriction fragments homologous to a Ha-ras probe. The other tumor contained an activated Ki-ras gene. Immunoprecipitation and NaDodSO4/PAGE analysis of p21 ras proteins in NIH 3T3 transformants derived from a majority of the hepatomas suggested that the activating mutations were localized in the 61st codon of the c-Ha-ras gene. Creation of a new Xba I restriction site by an AT----TA transversion at the second position of codon 61 was detected in DNA from primary tumors and NIH 3T3 cells transformed by DNA from 6 of 7 vinyl carbamate- and 5 of 10 1'-hydroxy-2',3'-dehydroestragole-induced hepatomas. Selective oligonucleotide hybridization demonstrated a CG----AT transversion at the first position of the 61st codon in NIH 3T3 transformants derived from 7 of 7 N-hydroxy-2-acetylaminofluorene-induced hepatomas. By the same criterion, an AT----GC transition at the second position of codon 61 was the activating mutation in 1 of 7 vinyl carbamate- and 5 of 10 1'-hydroxy-2',3'-dehydroestragole-induced tumors. Thus, c-Ha-ras activation is apparently an early event in B6C3 F1 mouse hepatocarcinogenesis that results directly from reaction of ultimate chemical carcinogens with this gene in vivo.