In the qPCR analysis, A2PP and truncated peptides A2PP-Nd4, Nd8, Nd12, Cd4, Cd8, and Cd12 reduced M. hyorhinis infection in gastric cancer cells, but A2PP-Nd16 and A2PP-Cd16 failed to decrease M. hyorhinis infection (Fig 6B). Here, MT-ND4 is linked to gastric cancer.