CXCR1 and Familial prostate cancer: For example, the expression of CXCR4 on melanoma cells was associated with increased rates of metastasis and patient mortality (Longo-Imedio et al, 2005), whereas another study suggests that interleukin-8 (IL-8) and its two chemokine receptors CXCR1 and CXCR2 might promote prostate cancer progression through autocrine signalling of prostate cancer cells (Murphy et al, 2005).