Accumulating evidences have demonstrated that intracellular Ca2+ homeostasis is altered in cancer cells, which is implicated in the regulation of JAK/STAT or NF‐κB signaling pathways.[17, 18] Moreover, tryptophan and Ca2+ ions cooperatively activate the human calcium‐sensing receptor, and L‐type calcium channels can modulate tryptophan hydroxylase in the rat pineal gland.[19, 20] However, it remains unknown whether calcium channels modulate tryptophan metabolism and blocking them can benefit in cancer immunotherapy. This evidence concerns the gene NFKB1 and cancer.