Currently, we are studying the mechanism of such suppression. In addition, we also found that a transcription factor, Egr-1, can suppress a number of human tumor cell growth. Some types of tumor cells and tumor tissue express little or no Egr-1, in contrast to their normal counterparts. The tumor suppression activity of Egr-1 may involve the coordinated expression of gene products important in the control of cell growth and differentiation. Egr-1. back to page ahead Tumor promotion and signal transduction Carcinogenesis process is generally believed to involve initiation and promotion.
Tumor promotion is a multifaceted process ultimately dependent on cell proliferation for completion.
Elucidation of molecular mechanism and signal pathway in the tumor promotion process will allow us to target chemoprevention of neoplastic disease more effectively and specifically. We found that H2O2 acts as tumor promoter in rat liver epithelial cells. The activation of EGFR brings about the phosphorylation of cx43 and interruption of gap junction communication as well as the induction of early growth response genes and the promotion of cell proliferation. These studies may provide new information about the initiation and the development of cancer.