Published online Dec 15, 2003. doi: 10.3748/wjg.v9.i12.2772
Revised: June 18, 2003
Accepted: August 16, 2003
Published online: December 15, 2003
AIM: To investigate the effect of complex amino acid imbalance on the growth of tumor in tumor-bearing (TB) rats.
METHODS: Sprague-Dawlley (SD) rats underwent jejunostomy for nutritional support. A suspension of Walker-256 carcinosarcoma cells was subcutaneously inoculated. TB rats were randomly divided into groups A, B, C and D according to the formula of amino acids in enteral nutritional solutions, respectively. TB rats received jejunal feedings supplemented with balanced amino acids (group A), methionine-depleted amino acids (group B), valine-depleted amino acids (group C) and methionine- and valine-depleted complex amino acid imbalance (group D) for 10 days. Tumor volume, inhibitory rates of tumor, cell cycle and life span of TB rats were investigated.
RESULTS: The G0/G1 ratio of tumor cells in group D (80.5 ± 9.0)% was higher than that in groups A, B and C which was 67.0% ± 5.1%, 78.9% ± 8.5%, 69.2% ± 6.2%, respectively (P < 0.05). The ratio of S/G2M and PI in group D were lower than those in groups A, B and C. The inhibitory rate of tumor in groups B, C and D was 37.2%, 33.3% and 43.9%, respectively (P < 0.05). The life span of TB rats in group D was significantly longer than that in groups B, C, and A.
CONCLUSION: Methionine/valine-depleted amino acid imbalance can inhibit tumor growth. Complex amino acids of methionine and valine depleted imbalance have stronger inhibitory effects on tumor growth.