We gathered normal and colorectal cancer tissues from 18 patients after tumor surgery. The tumor tissues represent caner stages from T1 to T4 (TNM system).Two-dimensional electrophoresis and MALDI-TOF techniques were utilized to identify the differentially expressed proteins. Our studies showed that there are about 18 differentially expressed proteins in normal and tumor tissues (p<0.05) which 13 proteins increased in tumor were Keratin 8, Protein disuflde isomerase A3 precursor, Keratin 18, Fractalkine precursor, LDH-B, Tropomyosin alpha 4 chain, Tropomyosin alpha 3 chain, chloride intracellular channel protein 1, PTTG1(Pituitary tumor-transforming protein 1),

Pituitary tumor-transforming gene 1 (PTTG1) encodes a multifunctional protein that is involved in many cellular processes. However, the potential role of PTTG1 in tumor formation and its prognostic function in human pan-cancer is still unknown. The analysis of gene alteration, PTTG1 expression, prognostic function, and PTTG1-related immune analysis in 33 types of tumors was performed based on various databases such as The Cancer Genome Atlas database, the Genotype-Tissue Expression database, and the Human Protein Atlas database. Additionally, PTTG1-related gene enrichment analysis was performed to investigate the potential relationship and possible molecular mechanisms between PTTG1 and tumors. Overexpression of PTTG1 may lead to tumor formation and poor prognosis in various tumors. Consequently, PTTG1 acts as a potential oncogene in most tumors. Additionally, PTTG1 is related to immune infiltration, immune checkpoints, tumor mutational burden, and microsatellite instability. Thus, PTTG1 could be potential biomarker for both prognosis and outcomes of tumor treatment and it could also be a promising target in tumor therapy.