MCT1 also known as SLC16A1 is a proton-linked monocarboxylate transporter that catalyzes the movement of many monocarboxylates, such as lactate and pyruvate, across the plasma membrane. MCT1 plays a crucial role in cellular metabolism by facilitating the transport of monocarboxylates such as lactate and pyruvate across the plasma membrane. This transport is vital for maintaining cellular energy homeostasis, particularly during anaerobic glycolysis, where lactic acid accumulates and can lead to a decrease in intracellular pH, ultimately inhibiting glycolysis if not efficiently exported. MCT1 is predominantly expressed in tumor cells and erythrocytes, making MCT1 a key player in cancer metabolism and a potential target for therapeutic interventions.