For instance, it was found that Programmed Cell Death 4 (PDCD4) is downregulated in ESCC.[11] Phosphoinositide dependent kinase 1 (PDK1) is reported to be upregulated in ESCC, which is associated with a poor prognosis.[12] In addition, microRNAs (miRNAs) are small noncoding RNA molecules of 20 to 25 nucleotides in length that participate in posttranscriptional regulation of gene expression. The gene discussed is PDK1; the disease is esophageal squamous cell carcinoma.