Antitumor activity of the protein and small molecule component fractions from Agrocybe aegerita through enhancement of cytokine production.

A water soluble extract from the medicinal mushroom Agrocybe aegerita has been shown to stimulate splenocyte proliferation, cytotoxic activity, and tumor rejection effect in tumor-bearing mouse models. In the present study, the crude extract was separated into a protein component fraction (Yp), mainly containing lectins and serine proteinase, and a small molecule component fraction (Ys), mainly containing triethylene glycol, α-bisabolol, n-hexadecanoic acid, and so on. The antitumor activity of the fractions was investigated in a tumor-bearing BALB/c mouse model. Repeat administration of Yp and Ys significantly inhibited tumor growth (P<.001), but little toxicity was observed. Moreover, the protein fraction Yp performed better than Ys in both antitumor and lifespan-prolonging activity. The cytokine expression levels in serum and splenocytes from extract-treated mice were selectively screened by enzyme-linked immunosorbent assay and quantitative real-time polymerase chain reaction, and the results showed that Yp upregulated the mRNA level of Th2 cytokine interleukin-10 (P<.01), and Ys increased the mRNA level of granulocyte-macrophage colony-stimulating factor (P<.01) and anti-inflammatory cytokine transforming growth factor-β (P<.01). All these data suggest that Yp and Ys can inhibit tumor growth via different mechanisms, which promotes the understanding of antitumor properties of medicinal fungi.