In 2016, Harada et al. summarized 18 non-targeted proteomic studies with limited sample sizes for ESCC diagnosis based on mass spectrometry technology using serum, tissue and cell line samples, and identified several novel ESCC diagnostic markers, such as Apolipoprotein A-I, Tubulin beta chain filamin A alpha, HSP70, and so on [22]. This evidence concerns the gene APOA1 and esophageal squamous cell carcinoma.