A novel antitumor protein from the mushroom Pholiota nameko induces apoptosis of human breast adenocarcinoma MCF-7 cells in vivo and modulates cytokine secretion in mice bearing MCF-7 xenografts

Nutritional Quality and Biological Application of Mushroom Protein as a Novel Protein Alternative

PURPOSE OF REVIEW

Global concerns about population growth, economic, and nutritional transitions and health have led to the search for a low-cost protein alternative to animal origins. This review provides an overview of the viability of exploring mushroom protein as a future protein alternative considering the nutritional value, quality, digestibility, and biological benefits.

RECENT FINDINGS

Plant proteins are commonly used as alternatives to animal proteins, but the majority of them are low in quality due to a lack of one or more essential amino acids. Edible mushroom proteins usually have a complete essential amino acid profile, meet dietary requirements, and provide economic advantages over animal and plant sources. Mushroom proteins may provide health advantages by eliciting antioxidant, antitumor, angiotensin-converting enzyme (ACE), inhibitory and antimicrobial properties over animal proteins. Protein concentrates, hydrolysates, and peptides from mushrooms are being used to improve human health. Also, edible mushrooms can be used to fortify traditional food to increase protein value and functional qualities. These characteristics highlight mushroom proteins as inexpensive, high-quality proteins that can be used as a meat alternative, as pharmaceuticals, and as treatments to alleviate malnutrition. Edible mushroom proteins are high in quality, low in cost, widely available, and meet environmental and social requirements, making them suitable as sustainable alternative proteins.

Isolation, Purification, and Antitumor Activity of a Novel Active Protein from Antrodia cinnamomea Liquid Fermentation Mycelia

Antrodia cinnamomea, a rare medicinal fungus endemic to Taiwan, contains numerous active components and displays strong antitumor and anti-inflammatory effects. We isolated and purified a novel A. cinnamomea active protein (termed ACAP) from liquid fermentation mycelia and evaluated its antitumor activity. A homogeneous protein-eluted fraction was obtained by anion exchange chromatography and gel filtration chromatography, and ACAP was identified based on the antitumor activity screening of this fraction. An in vitro assay of three tumor cell lines (HeLa, Hep G2, and Hepa 1-6) revealed significant antiproliferative effects of ACAP at low concentrations, with IC50 values of 13.10, 10.70, and 18.69 µg/mL, respectively. Flow cytometric analysis showed that ACAP induced late apoptosis of Hep G2 cells. The apoptosis rate of 50 µg/mL ACAP-treated cells (60%) was significantly (p < 0.01) more than that of the control. A Western blotting assay of apoptotic pathway proteins showed that ACAP significantly upregulated p53 and downregulated caspase-3 expression levels. Our findings indicate that ACAP has strong antitumor activity and the potential for development as a therapeutic agent and/or functional food.

Isolation of the Lanostane Triterpenes Pholiols L-S from Pholiota populnea and Evaluation of Their Antiproliferative and Cytotoxic Activities

Pholiols L-S (1−8), eight undescribed triterpenes were isolated from the sporocarps of the mushroom Pholiota populnea. Various chromatographic techniques, such as open column chromatography, flash chromatography, gel filtration, preparative thin layer chromatography, and HPLC, were applied to purify the compounds. The structure elucidation was carried out by spectroscopic analysis, including 1D (1H NMR and 13C JMOD) and 2D NMR (1H-1H COSY, HSQC, HMBC and NOESY) and HRESIMS experiments. The isolated compounds had lanostane (1−7) or trinorlanostane (8) skeletons; all of them were substituted with 3-hydroxy-3-methylglutaroyl group or its 6-methyl ester. Five compounds (1, 2, 4, 6, and 8) were investigated for their antiproliferative and cytotoxic activity in vitro by MTT assay on breast cancer (MCF-7), human colon adenocarcinoma (sensitive Colo 205, and resistant Colo 320), non-small cell lung cancer (A549), and human embryonic lung fibroblast (MRC-5) cell lines. Pholiols M (2) and O (4) showed antiproliferative activity against the MCF-7 cell line with IC50 of 2.48 and 9.95 µM, respectively. These compounds displayed tumor cell selectivity on MCF-7 cells with SI values of >40 (2) and 4.3 (4), but they did not show a cytotoxic effect, proving their action exclusively on tumor cell proliferation. Pholiols L (1) and Q (8) were found to have selective cytotoxicity on drug resistant cells in comparison to their effects on Colo320 and Colo205 cells [relative resistance values 0.84 (1) and 0.62 (8)].

Influence of Pholiota adiposa on gut microbiota and promote tumor cell apoptosis properties in H22 tumor-bearing mice

Hepatocellular carcinoma (HCC) is a common type of cancer-prevalent worldwide-and one of the causes of cancer-related deaths. In this study, ethanol extracts from Pholiota adiposa (EPA) were used to identify possible targets for HCC treatment and their effects on intestinal microflora were analyzed. Methods: Male mice were randomly assigned to groups-the model group, cyclophosphamide (25 mg/kg/d), and EPA groups, in which the mice were categorized based on the different concentrations of each compound (100, 200, and 300 mg/kg/day). Relevant biochemical indicators were detected using ELISA, H&E staining, and TUNEL assay. Four tumor apoptosis-related proteins and genes, Cleaved Caspases, BAX, Bcl-2, and VEGF, were detected by immunohistochemical staining, western blotting, and RT-PCR. The total genomic DNA was obtained from the contents of the small intestine and colon and was sequenced. The V3 + V4 regions of bacterial 16 s rDNA (from 341 to 806) were amplified. Results: The tests revealed that EPA exhibited antitumor activity in vivo by promoting apoptosis and inhibiting angiogenesis. Moreover, EPA treatment could increase beneficial and decrease harmful microflorae. These results demonstrate that EPA may be a potential therapy for HCC.

Structural characterization, anticancer, hypoglycemia and immune activities of polysaccharides from Russula virescens

Russula virescens is an edible wild mushroom that is widely distributed in south of China. This research aimed to analyze the structure characterization and evaluate the hypoglycemic, anticancer and immunological activities of two water soluble polysaccharides RVP-1 and RVP-2 from R. virescens. The results showed RVP-1 and RVP-2 were non-triple helix structured hetero-polysaccharides with different weight-average molecular weight 14,883 and 13,301 Da, respectively. Both RVP-1 and RVP-2 were composed of galactose, glucose, mannose and fructose, and the sugar residues were mainly linked by 1,6→, 1,2→, 1→ and 1,3,6→ glycosidic bonds. Moreover, the antidiabetic, anticancer and immune activities of RVP-1 and RVP-2 were explored in vitro methods. The two polysaccharides have potential for inhibiting α-glucosidase and α-amylase activities, suppressing HepG-2, A549 and MCF-7 cancer cells proliferation, and activating macrophage RAW 264.7 cells to secret immune cytokines for mediating cellular immune response. These findings provided a scientific basis for further utilization of polysaccharide from R. virescens.

Rutaecarpine administration inhibits cancer cell growth in allogenic TRAMP-C1 prostate cancer mice correlating with immune balance in vivo

BACKGROUND

Rutaecarpine (Rut) is a plant alkaloid abundant in Euodia ruticarpa which is a Chinese herbal medicine used for treating various cancers. However, the Rut administration effect on prostate cancer in vivo remains unclear.

AIM

In the present study we established an allogenic TRAMP-C1 prostate cancer mouse model to evaluate the Rut administration effect and mechanism in vivo.

METHODS

To unravel the Rut administration effect on prostate cancer in vivo, C57BL/6J male mice (8 weeks old) were randomly grouped (n = 9), subcutaneously loaded with TRAMP-C1 prostate cancer cells and immediately given daily by gavage with Rut dissolved in soybean oil at 7 mg (low dose), 35 mg (medium dose), and 70 mg/kg b.w./day (high dose) for successive 39 days.

RESULTS

Rut administration significantly and dose-dependently reduced both tumor volume and solid prostate cancer weight in allogenic TRAMP-C1 male mice. Rut administration markedly increased (TNF-α+IFN-γ) (Th1-)/IL-10 (Th2-) cytokine secretion ratios by splenocytes and TNF-α (M1-)/IL-10 (M2-) cytokine secretion ratios by macrophages as compared to those of dietary control group, suggesting that Rut administration in vivo regulates the immune balance toward Th1- and M1-polarized characteristics. Decreased CD19⁺, CD4⁺ and CD8⁺ lymphocytes in the peripheral blood of allogenic TRAMP-C1 mice were significantly elevated by Rut administration. Tumor weights positively correlated with TNF-α secretions by splenocytes, suggesting that there is a tumor cachexia in the tumor-bearing mice. Tumor weights negatively correlated with IgG (Th1-antibody) levels in the sera, suggesting that Th1-polarized immune balance may inhibit prostate cancer cell growth.

CONCLUSIONS

Our results evidenced that Rut administration suppresses prostate cancer cell growth in mice subcutaneously loaded with TRAMP-C1 cells and correlated the anti-cancer effects with Th1-polarized immune balance in vivo.