Abstract: AIM: To investigate the effects of carboxymethyl chitosan (CM-CTS) and adriamycin (ADM)on the proliferation of human cervical carcinoma cell line Hela and human colon cancer cells LS174- T in vitro. METHODS: The anti-proliferation activities of two drugs on tumor cells were evaluated by MTT assay.The jin's formula was used to analyze the experimental data. RESULTS: Both CM-CTS and ADM could inhibit tumor cell proliferation and an additional synergistic inhibitory effect could be improved when two drugs were combined.In sequential test, administration of ADM first followed by CM-CTS had a synergistic effect;but administration of CM-CTS first followed by ADM produced an antagonistic effect. CONCLUSION: Combined treatment with CM-CTS and ADM produces synergistic effects.Sequential administration of CM-CTS and ADM produces a unidirectional synergistic effect.

Key words: carboxymethyl-chitosan, adriamycin, MTT assay, Hela, LS174-T, synergistic action of drug