KLRK1 and cholangiocarcinoma: The 72Thr variant of NKC4 SNP (rs2255336) showed a protective effect against cervical cancer in Polish patients [36], and the rs11053781 and rs2617167 SNPs of NKG2D increased the risk of developing cholangiocarcinoma in a cohort of European patients with primary sclerosing cholangitis [31].