Given that the potential role of lactate in promoting EMT has been demonstrated in diseases such as myocardial infarction and diabetic nephropathy,12, 13, 14 we hypothesized the involvement of the PDK1 in mediating the EMT of HNECs via lactate under hypoxic conditions and tested this hypothesis using in vitro cultured HNECs. The gene discussed is PDK1; the disease is myocardial infarction.