| 摘 要： | Objective: To investigate the effect of the ethanol extract of Scutellaria barbata D. Don(EESB) on colorectal cancer(CRC) growth and Wnt/β-catenin signaling pathway in vivo and in vitro. Methods: In vivoexperiment, CRC xenograft mouse model was constructed with injection of HT-29 cells. Following xenograft implantation, twenty mice were randomly divided into EESB-treated group(n=10) and control group(n=10) by a random number table, and were given with intra-gastric administration of 2 g/kg EESB or saline, 5 days a week for 16 days, respectively. At the end of experiment, tumors were removed and weighed by electronic scales. The proliferation biomarker Ki-67 of tumor was evaluated by immunohistochemistry(IHC) assay. In vitro study, HT-29 cells were treated with 0, 0.5, 1.5, 2.5 mg/m L EESB for 24 h. At the end of the treatment, the viability and survival of HT-29 cells were determined by methylthiazolyldiphenyl-tetrazolium bromide(MTT) assay and colony formation assay, respectively. The m RNA expression of c-Myc, Survivin and adenomatous polyposis coli(APC) was examined by reverse transcription-polymerase chain reaction(RT-PCR) both in tumor tissues of CRC xenograft mice and HT-29 cells. Protein expression of c-Myc, Survivin, APC, and β-catenin as well as β-catenin phosphorylation level were evaluated by IHC assay or Western blotting. Results: EESB significantly reduced tumor weight in CRC xenografts mice, compared with the control group(P0.05). IHC assay showed that EESB significantly inhibited protein expression of Ki-67 in tumor tissues(P0.05). MTT assay showed that EESB significantly reduced HT-29 cell viability in a dose-dependent manner(P0.05). Colony formation assay showed that EESB dose-dependently decreased the survival of HT-29 cells(P0.05). In addition, RT-PCR assay showed that EESB decreased the m RNA expression of c-Myc and Survivin and increased APC expression, both in tumor tissues of CRC xenograft mice and HT-29 cells(P0.05). IHC assay or Western blotting showed that EESB decreased protein expression of β-catenin, c-Myc and Survivin, as well as increased APC expression and β-catenin phosphorylation in tumor tissues or HT-29 cells(P0.05). Conclusions: EESB significantly reduced tumor growth in CRC xenografts mice, and inhibited the viability and survival of HT-29 cells. EESB could suppress the activation of the Wnt/β-catenin pathway, which might be one of the mechanisms whereby Scutellaria barbata D. Don exerts its anticancer activity.
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