Manipulating the chemokine-chemokine receptor network to treat cancer.

Chemokines are chemoattractant cytokines that regulate the trafficking and activation of leukocytes and other cell types under a variety of inflammatory and noninflammatory conditions. Over the past few years, studies have increasingly shown that chemokines play an important role in several aspects of tumor progression. Tumor cells express functional chemokine receptors, which can sustain proliferation, angiogenesis, and survival and promote organ-specific localization of distant metastases. Chemokine expression in human malignancies is associated with a leukocyte infiltration favoring the establishment of immune escape mechanisms. A literature review of relevant publications on preclinical testing of cancer therapies based on interference with the cancer chemokine network was performed. The feasibility, potential advantages, and limitations of the clinical translation of the results of such studies in treatment of different tumor types and settings are discussed. The chemokine network is a key player in the establishment of metastases. In the preclinical setting, blocking agents and antibodies directed against CXCR4 prevent metastasis of different cancers. In mouse models, overexpression of selected chemokines causes tumor infiltration by distinct leukocyte subsets, resulting in tumor regression and tumor-specific immunity generation. Researchers have also successfully used chemokines as carriers and/or adjuvants for cancer vaccines. The cancer chemokine network is a multifaceted therapeutic target. Copyright 2007 American Cancer Society.