CD155 is expressed in a variety of normal tissues including the nervous, immune, and endothelial cells as well as the reproductive system. When the expression of CD155 increases, the probability of tumors appearing increases, so CD155 becomes one of the common features of many types of tumors. In tumors, the adhesive effect of CD155 not only affects the migration and invasion ability of tumor cells but also participates in the process of tumor angiogenesis and lymphangiogenesis. CD155 interacts with a variety of signaling molecules through its intracellular segment and participates in the regulation of cell proliferation, differentiation, and apoptosis. CD155 can act as a ligand for DNAM-1. CD155 can activate NK cells and T cells and promote the killing of immune cells; on the other hand, through binding to TIGIT and CD96, CD155 can prevent the activation and function of immune cells.

CD155 can activate the Ras-Raf-MEK-ERK signaling pathway to enable rapid cell proliferation, a pathway that plays a key role in cell growth, differentiation, and survival. CD155 interacts with the PI3K / Akt signaling pathway to alter the survival and migration rates of cells. PI3K / Akt signaling pathway is one of the important endocellular survival signaling pathways, which regulates cell proliferation, death, and metabolism. CD155 may also control cell migration and infection by participating in other signaling pathways (such as IL-6 / STAT 3, TGF- β/SMAD 3, etc.). These signaling pathways similarly play important roles in tumorigenesis and progression.

Fig 1: CD155 Gene Pathway. (Reference documentation: Molfetta R, Zitti B, Lecce M, Milito ND, Stabile H, Fionda C, Cippitelli M, Gismondi A, Santoni A, Paolini R. CD155: A Multi-Functional Molecule in Tumor Progression. Int J Mol Sci. 2020 Jan 30;21(3):922.)

Reference