CX3CR1 and neoplasm: Together with the decreases in Tim-3 and CX3CR1 levels in pNK cells after interaction with MCF-7 spheroids, these findings may indicate the involvement of the Tim-3/galectin-9 and CX3CR1/CX3CL1 pathways in the regulation of the cytotoxic response of pNK cells to MCF-7 tumor cells in the 3D model.