The multifarious roles of the chemokine CXCL14 in cancer progression and immune responses.

The chemokine CXCL14 is a highly conserved, homeostatic chemokine that is constitutively expressed in skin epithelia. Responsible for immune cell recruitment and maturation, as well as impacting epithelial cell motility, CXCL14 contributes to the establishment of immune surveillance within normal epithelial layers. Furthermore, CXCL14 is critical to upregulating major histocompatibility complex class I expression on tumor cells. Given these important roles, CXCL14 is often dysregulated in several types of carcinomas including cervical, colorectal, endometrial, and head and neck cancers. Its disruption has been shown to limit critical antitumor immune regulation and is correlated to poor patient prognosis. However, other studies have found that in certain cancers, namely pancreatic and some breast cancers, overexpression of stromal CXCL14 correlates with poor patient survival due to increased invasiveness. Contributing to the ambiguity CXCL14 plays in cancer is that the native CXCL14 receptor remains uncharacterized, although several candidate receptors have been proposed. Despite the complexity of CXCL14 functions, it remains clear that this chemokine is a key regulatory factor in cancer and represents a potential target for future cancer immunotherapies.