植物提取十八碳二烯酸对人胃癌组织细胞生态毒理学作用机制研究

为了探索植物提取十八碳二烯酸对人胃癌组织细胞生态毒理学作用机制,取胃癌患者肿瘤组织移植到重症联合免疫缺陷(SCID)小鼠皮下,腹腔注射100、300、900 mg·kg-1植物提取物十八碳二烯酸,分析对移植瘤生长抑制作用;用酶联免疫吸附法(ELISA)检测瘤组织cAMP、P53、PI3K水平.将瘤组织经酶解消化分离出细...

Ecotoxicological mechanism of the octadecadienoic acid extract on human gastric cancer cells

In order to understand the ecotoxicological mechanism of the extracted octadecadienoic acid from plant on human gastric cancer,the tumor tissues from the gastric cancer patients were transplanted subcutaneously into severe combined immunodeficiency(SCID)mice.The mice in different groups were respectively treated with 100,300 and 900 mg·kg^-1 extract intraperitoneally to evaluate the inhibitory effect on the growth of transplanted tumor cells and the levels of cAMP,P53 and PI3K with the enzyme-linked immunosorbent assay(ELISA).The tumor tissues were digested with enzyme for cell culture.The cultured tumor cells were administered 2.0,4.0 and 8.0 mg·L^-1 octadecadienoic acid extract,and the ecotoxicity of extract on gastric cancer cells was detected by MTT assay and the levels of P21,MDM2 and PKB/Akt were measured by ELISA.Our results showed that,after treated with different extract doses and 5-FU,compared with the control group,the growth inhibition rates of the transplanted gastric cancer were significantly increased by 17.92%-45.75%and 35.85%and the cAMP level increased by 14.88%-40.70%and 23.21%(P<0.05,P<0.01),respectively;while the P53 levels were decreased by 37.94%-63.96%and 58.54%(P<0.01)and the PI3K level decreased by 20.77%-52.94%and 35.29%(P<0.01),respectively.In addition,the numbers of living gastric cancer cells in the extract treated groups and the 5-FU group were decreased with the increase of the extract concentration and the prolongation of action time and the IC₅₀ was 5.811 mg·L^-1 and the inhibitory rates of cells proliferation by 23.11%-59.66%and 51.26%,respectively.The results from the flow cytometry showed that,when the gastric cancer cells were treated with different extract doses and the 5-FU,the G₀G₁ phase cells were increased by 16.54%-7.51%and 20.45%,respectively,while the G2M phase cells were decreased by 36.40%-67.98%and 41.67%,and the apoptosis rates were 17.44%-23.37%and 19.21%,respectively,compared with the control group.The results from the ELISA suggested that,when the gastric cancer cells were treated with different extract doses and the 5-FU,the levels of P21 and MDM2 in gastric cancer cells were increased by 13.33%-62.81%and 52.63%,and 10.26%-76.92%and 33.33%,respectively,while the levels of PKB/Akt were decreased by 19.39%-51.02%and 46.94%,respectively.Our findings indicate that the SCID mouse tumor model can be used as an ecotoxicological experimental model for human tumor treatment and rehabilitation.The octadecadienoic acid extract has significant ecotoxic and inhibitory effects on the proliferation of the transplanted gastric cancer and tumor cells.The potential mechanism may be related to the increases of the cAMP,P21 and MDM2 levels,the decrease of the PI3K,PKB/Akt and P53 levels,the inhibition of the cell division cycle,and the reduced activity of PI3K-Akt signal transduction pathway.