Published online Apr 15, 1998. doi: 10.3748/wjg.v4.i2.103
Revised: December 26, 1997
Accepted: February 24, 1998
Published online: April 15, 1998
AIM: To observe the effects of a chemically synthesized tetrose and a natural yeast mannan on experimental liver metastasis of mouse melanoma.
METHODS: After treated with 4mg tetrose (tetrose group) or 4 mg mannan (mannan group) for 30 min at 37 °C, 0.5 ml 1 × 106 B16-MBK melanoma cells were injected into the spleen of mice. Fifty-five days later, melanoma metastatic nodes on the surface of the liver and in other organs as well as mouse survival time were observed.
RESULTS: Of the 6 mice in control (B16 cell + PBS) group, 4 died naturally within 55 d, and 2 were killed on the 55th day. All of the 6 mice had metastases in livers, the total number of the melanoma nodes on each liver surface ranged from 2 to 30, with the largest one merging into the whole liver. One mouse had a neo-plasm in the remnant site of injection, and 3 had metastases in lungs. In contrast, of the 6 mice in tetrose group, only one died on the 50th day after injection, with 3 metastases in the liver, the largest being 10 mm in diameter, the other 5 mice survived until being dissected on the 55th day after injection and had no liver metastasis, but 3 of them had neoplasms in their remnant sites of injection. In mannan group, all of the 6 mice survived and no metastasis was seen except for 2 liver nodes in one mouse with the largest diameter of 1 mm. Neither tetrose nor mannan group had metastasis out of the liver, and the weight of liver in the two groups was significantly lower than those in the control group.
CONCLUSION: Both tetrose and mannan had the effects of preventing melanoma cells from experimental metastasis to and out of the liver, and prolonging the survival time of the mouse.