CELLULAR INTERACTIONS IN NASOPHARYNGEAL CARCINOMAS

Tumor cell population in nasopharyngeal carcinomas (NPC) is highly heterogeneous. In addition of being heavily infiltrated by nonmalignant leucocytes, malignant NPC cells can display various phenotypes in terms of epithelial maturation and viral gene expression. These various cell sub-populations communicate through membrane contacts, secretion of cytokines and exosomes. Understanding their interactions is crucial for the elucidation of tumor growth and immune escape as well as for designing better therapeutic approaches. This chapter deals with three major questions. (1) What are the local factors responsible for leucocyte attraction and retention in NPC tumors? (2) What are the suspected autocrine and paracrine mechanisms of tumor growth? (3) What are the mechanisms of tumor immune evasion which could explain the growth of malignant epithelial cells containing viral antigenic proteins in a context of local inflammation?