Cks1, P27Kip1 and Skp2 protein expression in colorectal cancer

    ZHAO Yong, GAO Jianª²Fei, ZHANG Biª²Cheng, DU Guangª²Zu

    Department of Oncology, Wuhan General Hospital, Guangzhou Military Area Command, Wuhan 430070, China

    ¡¾Abstract¡¿ AIM: To investigate the expression of Cks1 protein and its relationship with the expressions of Skp2, P27Kip1 and colorectal tumorigenesis. METHODS: Flow cytometry was used to detect the expressions of Cks1, Skp2 and P27Kip1 in 20 normal colorectal mucosas, 20 adenomas as well as 54 colorectal cancers. RESULTS: The expressions of Cks1 and Skp2 gradually increased in the order of normal mucosa, adenoma to colorectal cancer (P<0.05), while the expression of P27Kip1 gradually decreased in the same order (P<0.05). A strong correlation was found between the expressions of Cks1 and Skp2 (r=0.845, P<0.05) and a significant inverse relation was also observed between the expressions of Cks1 or Skp2 and of P27Kip1 (r=-0.752, P<0.05; r=-0.746, P<0.05 respectively). The expression of Cks1 was significantly associated with the loss of tumor differentiation (P<0.05), but not with lymph node metastasis and Dukes¬ð staging (P>0.05). CONCLUSION: Cks1 may play an important role in human colorectal tumorigenesis. Cks1 may be an essential factor in proteasomeª²dependent degradation of P27Kip1 regulated by Skp2. ......