CXCL17, or chemokine (C-X-C motif) ligand 17 is a cytokine, which has been identified in humans and mice. This small cytokine is a member of the CXC family of chemokines. CXCL17 is also known as VEGF co-regulated chemokine 1 or VCC-1, and dendritic-cell and monocyte-attracting chemokine-like protein or DMC. Chemokines are a group of signalling proteins, secreted by cells around the body. CXC chemokines are one of four subsections of chemokines. The other three include CC, CX3C and XC chemokines.CXCL17 is a relatively new amino acid CXC chemokine, which was identified in 2006. This CXC chemokine comprises of 119 amino acids. The CXCL17 gene is located on chromosome 19. The receptor for CXCL17 has been identified as GPR35/CXCR8.
The structure of CXCL17
CXCL17 spans approximately 15kb and it comprises four exons and three introns. The mass of human CXCL17 is estimated at 13.8 kDa. The mass of mouse CXCL17 is slightly lower at 13.6 kDa. CXCL17 comprises 119 amino acids.
Expression and mechanism
The CXCL17 gene is expressed in numerous sites within the body, including the trachea, lungs, stomach and skeletal muscle tissue. Research suggests that expression is focused on mucosal sites. There is still a way to go in terms of evaluation and analysis of cells that secrete CXCL17. However, immunohistochemistry has revealed that CXCL17 is expressed on the epithelium of the bronchioles in the lungs and in the villus and epithelial cells of the small intestine and colon. CXCL17 is also produced by a number of tumour types.
Investigations suggest that CXCL17 is expressed in cases of breast and colon cancer. In this case, CXCL17 behaves as a chemoattractant for different types of blood cells, including macrophages, monocytes and dendritic cells, which have not yet reached maturity. It is understood that CXCL17 plays an important role in the process of angiogenesis in the development of tumours. Analysis of clinical samples suggests that approximately 60 percent of cells are CXCL17-positive in cases of breast cancer and 50 percent of cells are CXCL17-positive in cases of colorectal cancer. Higher rates of CXCL17 are also linked to a poorer prognosis for patients.
Studies suggest interaction with CXCL8 in cases of breast cancer and interactions with CCL16, CCL17, CCL4, CCL5 and TSN.
CXCL17 is a chemoattractant, which is known to attract blood monocytes and under-developed dendritic cells and play a role in angiogenesis and tumour growth. Research suggests that CXCL17 is influential in the development of several different types of tumour cells, including those found in the colon and breast tissue and hepatocellular carcinoma. CXCL17 also has anti-inflammatory properties, most notably in the stomach cells, and it may play a role in the immune response against infections.
CXCL17 is a cytokine, which was added to the family of CXC chemokines in 2006. CXCL17 is expressed in mucosal cells located in several different parts of the body, and its primary function is to attract monocytes, macrophages and dendritic cells. CXCL17 is also known as DMC and VCC-1.