Experimental Study On Anti-tumor Action Of Chinese Medicine Gecko In Vitro And Vivo

Objective To study on acute toxicity testing of Gecko. To investigate the antitumor effect and mechanism of Gecko on human esophageal carcinoma cell lines In Vitro and xenografted sarcoma 180 in Kunming mice.To observe the influences of Gecko on immune system.To study the toxicity-decreasing and synergistic effects of Gecko on S180 mice treated by cytoxan(CTX).Methods Acute toxicity testing tried to figure out LD50 and maximum dosage of Gecko. The serum pharmacology method was used in vitro test. The growth rates of the human esophageal carcinoma cells(EC9706 or EC1)were measured by a modified MTT assay ;Viable cells were counted under microscope by trypan blue dye exclusion method and growth curves were drawn according to it. The transplanted tumor model of the mouse S180 sarcoma was established. Fifty mice were randomly divided into five groups (n = 10). Three Gecko groups were treated everyday with oral administration of Gecko powder at dose of 13.5g/kg, 9g/kg,4.5g/kg respectively. The control group (NS group) was treated with oral administration of an equal volume of saline as above everyday and the positive group (CTX group) was treated with 100 mg/kg Cytoxan by intraperitoneal injection at the first day. After two weeks of treatment, the anti-tumor activity was evaluated by tumor tissue weighing. The impact on immune organ was detected by accounting thymus index, spleen index, phagocytic rate and phagocytic index. The protein expression of vascular endothelin growth factor (VEGF) and basic fibroblast growth factor (bFGF) were detected by immunohistochemistry. The cell apoptotic rate was detected by TUNEL assay. In aspect of Gecko on both curative and negative effects of CTX. The transplanted tumor model of the mouse S180 sarcoma was established. Fifty mice were randomly divided into five groups (n = 10). Three Gecko and CTX groups, NS group and CTX group.After treatment, tumor tissue weighing, the peripheral white cells, thymus index and spleen index were detected. Results Acute toxicity testing didn't figure out LD50 of Gecko, The maximum dosage of Gecko given to the mice was more than 108 times than those given to patients on clinic.Serum of mice treated with Gecko power could inhibit EC9706 and EC1 growth and proliferation while Gecko powder could obviously inhibit S180 sarcoma of mice, the tumor inhibitory rate was 49.8%, 52.8% and 43.1%, respectively.However Gecko powder had no impact on immune organ. Moreover, Gecko powder could decrease VEGF and bFGF protein expression in tumor tissue and induce tumor cell apoptosis. In aspect of Gecko on both the toxicity-decreasing and synergistic effects of Gecko, the tumor inhibitory rate of three Gecko groups using with CTX were 63.9%,60.2% and 53.3%, the tumor inhibitory rate of CTX group was 35.6%.Gecko plus CTX obviously antagonized CTX-induced leucopenia, atrophy of immune organ.Conclusion Acute toxicity testing reveals that Gecko is quite safe for conventional oral use on clinic.Gecko has anti-tumor effects in vitro and in vivo.Induction of tumor cell apoptosis and the down-regulation of protein expression of VEGF and bFGF may be contributed to anti-tumor effects of Gecko.Gecko could enhance the curative effect of CTX in depressing tumor and attenuate the negative effect of CTX.