LRRC8C is a non-essential subunit of volume-regulated anion channels (VRACs) that forms heteromeric complexes with the obligatory LRRC8A subunit and other family members to regulate cell volume and ion transport 1. The protein plays critical roles in vascular function, where LRRC8C associates with LRRC8A and LRRC8B to form endothelial LRRC8 heteromers that regulate AKT-eNOS signaling, vascular reactivity, and blood pressure control 23. LRRC8C exhibits oxidant resistance compared to other family members, maintaining channel activity in oxidized microenvironments and supporting NADPH oxidase 1-mediated superoxide production 4. The channel conducts various anions and organic osmolytes, and mediates transport of immune signaling molecules like cGAMP 5. Pathogenic de novo variants in LRRC8C cause constitutive channel activation, leading to a multisystem disorder affecting blood vessels, brain, eyes, and bones 1. Additionally, genetic variants in LRRC8C are associated with hypertension in humans and may influence survival outcomes in non-small cell lung cancer patients 26. These findings establish LRRC8C as having non-redundant functions in vascular physiology and disease susceptibility.