Guided Tour of Cell Migration: Signals and Pathways

Cell migration is not an intrinsic property of the cell, but a process that is regulated by extracellular signal substances and a multitude of external factors from other tissues and organ systems within the body. Accordingly, several studies demonstrate a strong influence of cytokines/chemokines, neurotransmitters and adipocytokines (soluble factors derived from fat cells) on the migratory behavior of immune cells as well as tumor cells. The migration of leukocytes is a key feature to fight cancer cells, whereas the locomotion of tumor cells is a prerequisite for tumor formation and metastasis. The impact of these substances differs depending on the cell type and the signal transduction pathways used. All these signaling molecules bind to varying receptor types and mediate their effects on cell migration via multiple signaling pathways. To illuminate the interplay between the nervous system, the immune system, adipocytes and tumor cells, we herein summarize in vitro and in vivo experiments with regard to cell migration, and deliver insight into the underlying signal transduction pathways.