Objective: Our aim was to investigate expression of Ki-67 and phosphorylated serine-threonine protein kinase (pAkt) in colorectal cancer tissues and their clinical significance, providing evidence for clinical diagnosis and treatment of colorectal cancer. Methods: A total of 80 patients pathologically diagnosed with colorectal cancer were selected. Streptavidin-Peroxidase immunohistochemical assay was used to detect positive expression rates of Ki-67 and pAKT in 80 cases of colorectal cancer tissue (CRC group), 80 cases of colorectal cancer adjacent tissue (adjacent group), and 20 cases of normal colorectal tissue (normal group). Correlation of expression of Ki-67 and pAKT in cancer tissues of CRC patients with metastasis, stage, and prognosis of colorectal cancer were analyzed. Spearman's correlation analysis was then adopted to analyze the relationship between Ki-67 expression and pAKT expression. Results: Positive expression rates of Ki-67 and pAKT in colorectal cancer group were significantly higher than those in the adjacent group and normal group (P<0.001, P<0.001, P=0.012; P<0.001, P=0.011, P=0.024). Positive expression rates of Ki-67 and pAKT in cancerous tissue of patients with lymph node metastasis were overtly higher than those in cancerous tissue of patients without lymph node metastasis (P=0.013, P=0.009). Positive expression rates of Ki-67 and pAKT in cancer tissue of patients with stage I+II cancer were clearly lower than those in cancer tissue of patients with stage III+IV cancer (P=0.003, P=0.002). There was positive correlation between expressions of Ki-67 and pAKT (r=0.520, P=0.020). Overall survival of patients with negative Ki-67 expression was statistically longer than those of patients with (+), (++) and (+++) of Ki-67 (P=0.021, P=0.022, P<0.001). In addition, overall survival of patients with negative pAKT expression showed statistically longer survival compared with those with (+), (++) and (+++) of pAKT (P=0.011, P=0.012, P=0.001). Conclusion: Abnormal expression of Ki-67 and pAKT was closely related to occurrence and development of colorectal cancer and upregulated expression of Ki-67 and pAKT was involved in the formation, development, invasion, and metastasis of tumors. They could be used as clinical markers determining the biological behavior of colorectal cancer.
