SLC6A6 (solute carrier family 6 member 6) functions as a sodium- and chloride-dependent transporter primarily responsible for taurine uptake across cellular membranes 12. The protein localizes to both plasma membrane and mitochondria, where it imports taurine essential for mitochondrial transfer RNA modifications and translation 2. SLC6A6 also transports beta-alanine and can mediate GABA transport. Beyond its transport function, SLC6A6 plays critical roles in cellular metabolism and immune regulation. In cancer contexts, tumor cells overexpress SLC6A6 to outcompete CD8+ T cells for taurine, leading to T cell exhaustion and immune evasion through ATF4-mediated upregulation of immune checkpoint genes 1. The transporter is regulated by protein kinase A for subcellular localization and by NFAT5 for mitochondrial function 2. SLC6A6 expression is elevated in gastric cancer and correlates with poor prognosis, potentially due to hypomethylation 3. In vascular biology, SLC6A6 suppresses smooth muscle cell proliferation and migration via Wnt/β-catenin signaling inhibition 4. Therapeutically, targeting SLC6A6 or taurine supplementation shows promise for cancer treatment and liver fibrosis management 5.