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Colorectal cancer(CRC) is a kind of malignant tumor that occurs in the digestive tract. CRC occurs globally and has high rates of morbidity and mortality. Its incidence and mortality are second only to gastric cancer, esophageal cancer, and primary liver cancer in digestive system malignancies. Most CRC cases are adenomas. A few are squamous epithelial cancers, which can spread to adjacent tissues and organs through lymph and blood circulation, or directly. The occurrence of CRC is related to factors that include gene mutation, dietary habits, family disease history, smoking, drinking, and external carcinogens. Diagnostic methods for CRC mainly include digital rectal examination, X-ray barium enema, sigmoidoscopy, and fiber colonoscopy. However, low sensitivity of detection is a problem, and false positives still occur. Thus, screening for specific over-expressed genes as biomarkers is meaningful in the clinic for diagnosis. Additionally, several reports have discussed molecular mechanisms associated with the occurrence of CRC, such as the K-Ras and p53 signaling pathways. The crucial pathways have not been identical. Data of clinical samples from bioinformatics databases with information of gene expression on a large scale may reveal significant pathways that are involved in cancer development [1]. The Gene Expression Omnibus (GEO) database includes information acquired globally using many gene chips. The data include clinically relevant expression of genes and several types of RNA, including messenger RNA (mRNA), micro RNA (miRNA), and long noncoding RNA(lncRNA), and data of DNA methylation. Clinical data can be …