Prognostic value of innate and adaptive immunity in cancers

Abstract

Cancer remains one of the most complex diseases affecting humans and, despite the impressive advances that have been made in molecular and cell biology, how cancer cells progress and acquire their metastatic ability still remains debated. Tumors are heterogeneous cellular systems whose growth depends on dynamical interactions among the cancer cells, and between cells and the constantly changing microenvironment. Several types of immune cells, including cells of both the innate and adaptive immune system, are comprised in the microenvironment of human cancers. While chronic inflammation is considered as one of the hallmarks of cancer being associated to increased risk of tumor development and progression, the clinical relevance of innate and adaptive cellular components of the immune system is still today less clear. A relevant issue is to unravel the discrepancy between the inhibitory effects on cancer growth exerted by the local immune response and the promoting effects on cancer proliferation, invasion, and dissemination induced by some types of inflammatory cells. Here, we discuss the actual knowledge on the role played by innate and adaptive immune system in the local progression and metastasis of human cancer of unrelated histological origin and the prognostic information that we can currently understand and exploit.