Expression of ADAM29 and FAM135B in the pathological evolution from normal esophageal epithelium to esophageal cancer: Their differences and clinical significance

A Disintegrin And Metalloprotease Domain 29 (ADAM29) and Family with sequence similarity 135 member B (FAM135B) genes have been reported to be associated with a carcinogenic risk of esophageal squamous cell carcinoma (ESCC). However, to the best of our knowledge, the expression of ADAM29 and FAM135B in the pathological evolution from normal esophageal epithelial cells to ESCC has not yet been investigated. The present study aimed to investigate the expression of ADAM29 and FAM135B in normal esophageal mucosal epithelium, low-grade and high-grade esophageal intraepithelial neoplasia, and ESCC. Furthermore, the present study aimed to investigate the role of ADAM29 and FAM135B in the development of esophageal lesions. Immunohistochemistry was performed in order to detect the expression levels of ADAM29 and FAM135B proteins in normal esophageal mucosa samples (40 cases), low-grade intraepithelial neoplasia samples (20 cases), high-grade intraepithelial neoplasia samples (20 cases) and ESCC samples (40 cases). The results of the present study demonstrated that the positive rates of ADAM29 and FAM135B proteins increased gradually from normal esophageal mucosal epithelium and esophageal intraepithelial neoplasia, to ESCC (P<0.05). Furthermore, the expression levels of ADAM29 and FAM135B proteins in ESCC were not associated with age and the tumor size (P>0.05); however, the protein levels were associated with the pathological stage, clinical stage and lymph node metastasis of ESCC (P<0.05). In addition, there was a significant association between the expression levels of ADAM29 protein and FAM135B protein (χ(2)=60.071; P<0.001). The results of the present study demonstrated that the expression levels of ADAM29 and FAM135B were associated with the tumor behavior characteristics and the progression of esophageal cancer, the expression of which could be used for the diagnosis of early esophageal cancer, and provide the basis for guiding individualized treatment.