MCT-1 protein protects against apoptosis. Annexin V binding assay by flow cytometry was performed to compare cell apoptosis induction in EC155-Vector⁵ and EC155—MCT-1⁷  cell lines. After 72 hours of serum starvation, total annexin V-positive cells of the EC155—MCT-1⁷  line was significantly less than that of EC155-Vector⁵  (20.1% vs 33.8%). Similar results were obtained with other MCT-1 overexpressing clones. The data suggest a protective function of MCT-1 against apoptosis induced by serum starvation.