Prokineticin 2 (PROK2) is an important factor for angiogenesis in colorectal cancer

The Prokineticin 2 (PROK2) is correlated with indispensable in maintaining the homeostasis of healthy human tissues. Herein, we examined the role of PROK2 in human colorectal cancer. After total RNA extraction from 6 colorectal cancer cell lines, we examined the expression of PROK2 mRNA. For investigating angiogenesis and tumor growth in mice, the PROK2 gene was transfected into colorectal cancer cell lines having low PROK2 mRNA expression. In addition, small interfering RNA (siRNA) was transfected into colorectal cancer cell lines having high PROK2 mRNA expression for investigation of angiogenesis and tumor growth in mice. From 6 colorectal cancer cell lines studied, PROK2 mRNA expression was increased in 3 cell lines. When the PROK2 gene was transfected into the colorectal cancer cell line with low PROK2 mRNA expression, angiogenesis and tumor growth in mice increased significantly compared to the cell line with the control vector. When PROK2 siRNA was transfected into colorectal cancer cell lines with high PROK2 mRNA expression, angiogenesis and tumor growth in mice were suppressed significantly compared to the cell line with siRNA (control). This is the first report of the association of PROK2 as an angiogenic growth factor in colorectal cancer.