Schizophyllum commune fruiting body polysaccharides inhibit glioma by mediating ARHI regulation of PI3K/AKT signalling pathway

Glioma poses a serious threat to human health and has a high mortality rate. Therefore, developing natural anti-tumour drugs for cancer treatment is an urgent priority. Schizophyllum commune is an edible and medicinal fungus, with polysaccharides as its main active components, which may have anti-tumour properties. Herein, we characterised S. commune fruiting body polysaccharides (SCFP) structure and evaluated its anti-glioma activity in vitro and in vivo. UV and FTIR spectra, high-performance gel chromatography, and monosaccharide composition analyses demonstrated that SCFP was a heteropolysaccharide with a molecular weight of 290.92 kDa. Among the monosaccharide compositions, mannose, galactose, and glucose were the most abundant. SCFP significantly inhibited the survival of the glioma cell lines U251 and U-87MG. U251 xenograft tumours treated with SCFP via gavage showed a 47.39 % inhibition, with no significant toxic side effects observed. SCFP upregulated aplasia Ras homologue member I (ARHI) expression, thereby regulating PI3K/AKT signalling, inhibiting tumour migration, and inducing apoptosis, to inhibit tumour growth. Furthermore, SCFP treatment increased the relative abundance of beneficial bacteria, including Akkermansia muciniphila, Ligilactobacillus murinus, and Parabacteroides goldsteinii, in tumour-bearing mice and restored the gut microbiota structure to that of the normal group (NG group) mice without tumours. Thus, SCFP has the potential for application as a natural anticancer drug.