XCR1 and neoplasm: Intense interactions between GZMAhigh NK cells and DCs and between XCL1high NK cells and DCs via XCL1/XCL2-XCR1 and FLT3LG-FLT3 (Fig. 6H and Additional file 1: Fig. S13F) pairs were detected, suggesting that GZMAhigh and XCL1high NK cells may recruit and activate DCs into the tumor site.