OBJECTIVE: To establish a rat model of liver cancer complicated by liver cirrhosis and explore the effects of the spleen on immune function in this model.
METHODS: Liver cirrhosis was inflicted in rats by percutaneous injection of 40% CCl4 on the back. Walker-256 tumor cells were inoculated in the cirrhotic liver and splenectomy was performed. Two weeks later, the growth and metastasis of tumor were observed and the amount of ascites and the activity of NK cells and CD25 cells were investigated.
RESULTS: The amount of ascites and tumor volume were significantly higher in splenectomy group than in controls (P<0.01). Two weeks after inoculation, the activity of NK cells in both groups was decreased as compared with that before the inoculation (P<0.01). There was no significant difference between the two groups before and after the inoculation (P>0.05). The number of CD25 in both groups was higher than that before the inoculation (P<0.01). However, there was no significant difference between the two groups before and after the inoculation (P>0.05).
CONCLUSIONS: Splenectomy in early stage of tumor inoculation can stimulate the tumor growth and metastasis. The activity of NK cells and the number of CD25 are inhibited by tumor itself, not by splenectomy.