Shuin T, Billings P C, Lillehaug J R, Patierno S R, Roy-Burman P, Landolph J R
Cancer Res. 1986 Oct;46(10):5302-11.
c-abl, c-fos, c-Ha-ras, c-myc, and c-mos were expressed whereas c-sis, c-fms, c-rel, c-src, and c-myb expression was not detectable in C3H/10T1/2 Cl 8 (10T1/2) cells and in eight chemically and radiation-transformed 10T1/2 cell lines. The expression of c-abl, c-fos, c-Ha-ras, and c-myc was growth-related in nontransformed 10T1/2 cells. c-abl and c-fos expression increased at confluence by 5- and 9-fold, respectively, compared to that in log phase cells. c-Ha-ras and c-myc transcripts were most abundant in log phase cells and decreased by 70 and 50%, respectively, in confluent cells. There were no significant growth-related changes in the expression of c-Ha-ras, c-myc, or c-abl in methylcholanthrene-transformed Cl 15 cells. The c-fos transcript was not detected in Cl 15 cell cultures. c-abl, c-fos, c-ras, and c-myc were expressed in whole C3H mouse embryo tissue, mouse liver, and 10T1/2 cells. Sizes of these protooncogene transcripts in 10T1/2 cells were the same as those in whole embryo tissue, except that 10T1/2 cells did not express the 8.2-kilobase abl transcript. At subconfluence, equivalent low levels of c-mos expression were observed in nontransformed and in the eight transformed 10T1/2 cell lines. The level of c-abl expression was similar in the nontransformed and in the eight transformed cell lines, but there was a new 8.2-kilobase transcript in the transformed MCA Cl 15 cell line. c-fos was expressed in 10T1/2 cells but was not detectable or greatly reduced in eight transformed cell lines. c-Ha-ras was expressed to a similar extent in eight transformed cell lines and in nontransformed 10T1/2 cells. In the UVC-4 transformed cell line, extra 3.3-kilobase Ha-ras and 7.5-kilobase Ki-ras transcripts were observed. c-myc was expressed at 4- to 7-fold higher levels in six transformed cell lines compared to 10T1/2 cells. There were no major rearrangements in or amplification of the c-myc gene in three transformed cells overexpressing this gene 5-fold. These studies show that enhanced expression of c-myc and decreased expression of c-fos correlate with the chemically and radiation transformed states of 10T1/2 cells. Changes in c-fos and c-myc oncogene expression may be casually linked to late stages of neoplastic transformation in these chemically and radiation transformed 10T1/2 cell lines.
在C3H/10T1/2 Cl 8（10T1/2）细胞以及8种化学和辐射转化的10T1/2细胞系中，c-abl、c-fos、c-Ha-ras、c-myc和c-mos有表达，而c-sis、c-fms、c-rel、c-src和c-myb的表达未被检测到。在未转化的10T1/2细胞中，c-abl、c-fos、c-Ha-ras和c-myc的表达与生长相关。与对数期细胞相比，汇合时c-abl和c-fos的表达分别增加了5倍和9倍。c-Ha-ras和c-myc转录本在对数期细胞中最为丰富，在汇合细胞中分别减少了70%和50%。在甲基胆蒽转化的Cl 15细胞中，c-Ha-ras、c-myc或c-abl的表达没有与生长相关的显著变化。在Cl 15细胞培养物中未检测到c-fos转录本。c-abl、c-fos、c-ras和c-myc在整个C3H小鼠胚胎组织、小鼠肝脏和10T1/2细胞中均有表达。10T1/2细胞中这些原癌基因转录本的大小与整个胚胎组织中的相同，只是10T1/2细胞不表达8.2千碱基的abl转录本。在亚汇合时，在未转化的和8种转化的10T1/2细胞系中观察到相当低水平的c-mos表达。c-abl的表达水平在未转化的和8种转化的细胞系中相似，但在转化的MCA Cl 15细胞系中有一个新的8.2千碱基转录本。c-fos在10T1/2细胞中有表达，但在8种转化细胞系中未被检测到或大大减少。c-Ha-ras在8种转化细胞系和未转化的10T1/2细胞中的表达程度相似。在UVC-4转化细胞系中，观察到额外的3.3千碱基Ha-ras和7.5千碱基Ki-ras转录本。与10T1/2细胞相比，c-myc在6种转化细胞系中的表达水平高4至7倍。在3种该基因过表达5倍的转化细胞中，c-myc基因没有重大重排或扩增。这些研究表明，c-myc表达增强和c-fos表达降低与10T1/2细胞的化学和辐射转化状态相关。在这些化学和辐射转化的10T1/2细胞系中，c-fos和c-myc癌基因表达的变化可能与肿瘤转化的后期阶段存在偶然联系。
