OBJECTIVE: To determine the efficacy of Scutellaria barbata flavonoids and polysaccharides on Ishikawa endometrial carcinoma cells co-cultured with U937 macrophages.METHODS: The presence of CD163 and CD206 was determined by flow cytometry. Thiazolyl Blue Tetrazolium Bromide assays were used to assess the proliferation effect of tumor-associated macrophages(TAMs) on Ishikawa cells. The secretion of interleukin(IL)-10 in the co-culture conditioned media was examined using an enzyme-linked immunosorbent assay. The protein expression levels of Toll-like receptor 4(TLR4), myeloid differentiation factor 88(MyD88) and nuclear factor(NF)-κB p65 were detected by Western blot. The mRNA expression levels of TLR4 and MyD88 were analyzed by real-time polymerase chain reaction(PCR). The expression levels of IL-12, IL-1β and tumor necrosis factor-α(TNF-α) were evaluated with real-time PCR.RESULTS: Compared with the U937 control group,the expression levels of CD163 and CD206 in the TAM group were higher(P < 0.05). TAMs co-cultured with Ishikawa cells for 24 or 48 h showed higher proliferation rates(P < 0.05). The expression levels of IL-12 decreased than compared with those in the U937 untreated group(P < 0.05). The expression levels of CD206, CD163, IL-10, IL-1β and TNF-α, NF-κB p65 and TLR4/MyD88 in the TAMs control group were greater than those in the U937 untreated group(P < 0.05) and those of the Scutellaria barbata flavonoids group(P < 0.05).CONCLUSION: Scutellaria barbata flavonoids may inhibit TAM activation by blocking the TLR4/MyD88/NF-κB signaling pathway.