P2RX7 and Familial prostate cancer: Firstly, we analyzed the mRNA expression of P2X7 in prostate cancer cells 1E8, 2B4 and 22RV1 as well as in non-malignant immortalized prostate epithelial cell BPH1 using real-time PCR, and found that P2X7 was markedly expressed in 1E8 and 2B4 prostate cancer cells, while its expression was very faint in 22RV1 and BPH1 cells (Fig. 1A).