Regulative role of the CXCL13-CXCR5 axis in the tumor microenvironment

Chemokines are best known for their abilities of recruiting immune cells and forming lymphoid tissue. Through interactions between chemokines and their receptors, various immune cell subsets are recruited into the tumor microenvironment which is the primary location for tumor cells interacting with responding host cells. In recent decades, a large volume of studies have revealed chemokines' role in the tumor microenvironment in regulating tumor growth, invasion, and/or metastasis as well as tumor immune response; however, their molecular mechanisms are not well understood. Recently, increasing evidence has reported the importance of the CXCL13-CXCR5 axis in the tumor microenvironment of various human malignancies. Thus, in this review, we will focus on the CXCL13-CXCR5 axis and elaborate on the expression patterns, regulating and corresponding regulatory mechanisms as well as clinical values in a wide range of human cancers.