Esophageal cancer is one of the most aggressive cancers in the world and the sixth leading cause of cancer-related death[17]. Histologically, the subtypes of esophageal squamous cell carcinoma in Asia has the highest incidence. Escc's pathogenesis is related to multiple factors including race, genetics and dietary intake[18]. The main treatments for ESCC include surgery, chemotherapy and radio-chemotherapy. However, the 5-year survival rate of patients with esophageal cancer remain low (<15%)[19]. It is of utmost importance to understand the pathogenic mechanisms of ESCC and develop effective strategies to treat ESCC. We need to improve our understanding of the pathogenesis of esophageal squamous cell carcinoma through molecular biology research. Microarray technology has allowed us to explore the genetic alterations of ESCC, and has been proved to be a useful method for identifying new biomarkers in other diseases. In this study, four microarray data sets were analyzed to obtain DEGs between esophageal squamous cell carcinoma tissue samples and healthy control tissue samples. A total of 105 DEGs were identified in these four data sets, including 63 up-regulated genes and 42 down-regulated genes. GO and KEGG enrichment analyses were performed to explore the interaction between the DEGs. The up-regulated genes were mainly enriched in extracellular matrix organization,the breakdown of collagen in the extracellular matrix,extracellular matrix disassembly ,hemidesmosome assembly,the extracellular matrix (ECM) -receptor interaction, protein digestion and absorption, and cell-matrix adhesions, while the down-regulated genes were mainly enriched in cellular response to xenobiotic stimulus hypodermal cell differentiation, negative regulation of cell migration cell differentiation, and extrinsic component of membrane cell cortex. Increasing evidence shows that a comprehensive understanding of the molecular composition of esophageal cancer requires attention not only to tumor cells but also to the tumor microenvironment[20]. The cells are surrounded by the extracellular matrix (ECM), the complex network consisting of molecules, proteins, and polysaccharides. Related research shows that cancer-related fibroblasts secrete growth factors and change the ECM to create a tumor niche and enhancing tumor cell migration and metastasis[20]. Extracellular matrix (ECM) remodeling plays a key role in tumor formation and progression, especially invasion[21]. Stromal cells such as fibroblasts secrete ECM remodeling enzymes, such as lysyl oxidase (LOX) and matrix metalloproteinase (MMP), which can help with the formation of primary tumors or metastatic micro-ecologies and the down-regulation of cell adhesion to achieve invasion, migration and intravascular infiltration[22, 23]. ECM remodeling is associated with esophageal cancer, especially ESCC. For example, LOX-L2 is overexpressed in more than 90% of ESCC[24]. In addition, several matrix metalloproteinases (MIMPs) in ESCC, including MMP-2, MMP-7, and MMP-9, are all up-regulated and related to tumor stage[25]. These theories are consistent with our results. 18 hub genes were identified from the PPI network, and 3 of these genes, namely CDKN3, RAD51AP1, and KIF4A, were related to DFS in ESCC patients. The high expression levels of these genes were related to a shorter DFS and the poor prognosis of patients with esophageal cancer. Cyclin-dependent kinase inhibitor 3 (CDKN3) performs crucial roles in the modulation of tumor development. Many previous studies reported that CDNK3 plays an inhibitory role in tumor development [26]. New research finds that CDKN3 plays different roles in different types of cancer. CDKN3 is reported to be involved in the occurrence and development of some types of tumors [27, 28]. CDKN3 facilitated the promotion of ESCC cell proliferation, invasion and migration by activating the AKT signaling pathway[29]. CDKN3 knockdown significantly inhibited ESCC cell proliferation, migration, and invasion, and suppressed the G1 / S transition of tumor cells, providing a potential target for ESCC treatment[29]. RAD51-associated protein 1 (RAD51AP1) is an emerging protein that is essential for RAD51-mediated Homologous recombination (HR). HR serves to repair DNA double-strand breaks and damaged replication forks, which is essential for maintaining genome stability and suppressing tumors. However, there are no reports about the clinical value of RAD51AP1 in ESCC. Related studies have found that the expression of RAD51AP1 is up-regulated in primary hepatocellular carcinoma and intrahepatic bile duct cancer[30, 31]. High expression of RAD51AP1 is associated with shortened survival in patients with breast and ovarian cancer[32, 33]. Although the exact molecular role of RAD51AP1 in cancer development and progression has not been fully understood, research has uncovered a possible link between RAD51AP1 and tumor metastasis. Studies have reported that the high expression of RAD51AP1 is associated with poor prognosis in patients with breast and ovarian cancer[34]. In some tumor cells and tissues, the increased RAD51AP1 may be related to the advantages of selective growth, enabling the replication of early tumor cells and metastatic cells[35, 36]. However, we still don't know the precise molecular mechanisms by which RAD51AP1 carries out the HR reaction in cells and stabilizes DNA replication forks, and how posttranslational modifications affect the activities and biology of RAD51AP1. Therefore, we need to further study and explore the impact of RAD51AP1 on the pathogenesis and prognosis of ESCC. Filling the knowledge gap in the above fields will also provide prospects for targeted treatment of high RAD51AP1 cancer. Human kinesin family member 4A (KIF4A) is a 140 kD protein that plays a key role in a variety of cellular processes, including chromosome condensation and segregation, cytok inesis during mitotic division, and middle-spindle formation [37, 38] Recently, it has become apparent that KIF4A plays an essential role in cancer development and progression. Recent studies have discovered that KIF4A might serve as a biomarker in breast cancer based on bioinformatics analysis[39]. KIF4A overexpression is observed in colorectal cancer and pancreatic ductal adenocarcinoma as well as in lung cancer, for which it is an independent prognostic risk factor[40-42]. However, the clinical value of KIF4A in esophageal squamous cell carcinoma is rarely mentioned. In the future, in-depth studies on the roles of KIF4A in ESCC might provide new clues for inhibiting ESCC.