OBJECTIVETo observe the effects of Lignum Sappan (LS) on the growth and metastases of transplanted Lewis lung carcinoma (LLC) in mice and investigate its partial mechanism of action.

METHODSC57BL/6 mice were established in LLC model and divided into six groups in random: Group A was untreated; Group B was treated by chemotherapy (CM) only; Groups C-F were treated respectively with low-dose LS, high-dose LS, CM + low-dose LS and CM + high-dose LS, via intragastric administration for 21 successive days. Mice were sacrificed in batches at different time points (d 7, d 14 and d 21) to observe the tumor inhibition rate and the metastases suppressing rate was measured dynamically. Meantime, the CD44 expression in tumor cells was measured by flow cytometry and serum P-selectin concentration was measured by ELISA assay.

RESULTSTumor weight in all treated groups, except Group C, was lower than that in Group A at the three time points (P < 0.05, P < 0.01), and that was lower in Group F than in Group B at the corresponding time points (P < 0.05, P < 0.01). Comparisons of CD44+ in tumor cells showed that as compared with Group A, on d 7, it was lower in Groups B and D (P < 0.01); on d 14, it was lower in Group E (P < 0.01) and Group F (P < 0.05); and on d 21, it was lower in Groups E and F (P < 0.01). As for the concentration of P-selectin, the intergroup comparisons showed that it was lower in Groups B-F on d 7 and in Group F on d 21 than that in Group A (P < 0.05 or P < 0.01), but showed insignificant difference in comparing the Group A with all the treated Groups on d 14 (P > 0.05).

CONCLUSIONLS and CM +LS could inhibit the growth and metastases of LLC, and shows inhibition on CD44 expression in tumor cells and P-selectin level in serum, which may be one of the mechanisms of LS in suppressing tumor metastasis.