Simultaneous over-expression of insulin-like growth factor-II (IGF II) and IGF-II receptor (IGF-II R) genes in human primary cancer-implication of autocrine and paracrine mechanism in autonomous growth of hepatic cancer

This is first report about the simultaneous over-expression of both Insulin-like growth factor (IGF-II) and its receptor (IGF-II R) at mRNA level in human primary hepatic Cancer (PHC). In 10 PHC samples from China, IGF-II and IGF-II R were both over-expressed, whereas only a background signal was detected in normal liver. In 5 pairs of PHC and its non-tumorous adjacent liver tissues from South Africa, IGF-II and IGF-II R were also over-expressed in PHC. mRNA expression of IGF-II in all 5 cases and IGF-II R in 4 of 5 cases were higher in cancer than non-tumorous adjacent liver tissues. These results strongly implicate that an autocrine and/or paracrine mechanism might be involved in formation and progression of PHC.