Fungal antitumor protein D1 is internalized via endocytosis and inhibits non-small cell lung cancer proliferation through MAPK signaling pathway

Lung cancer has the highest mortality among cancer-related deaths worldwide. Among lung cancers, non-small cell lung cancer (NSCLC) is the most common histological type. In the previous research, we isolated a protein (D1) from Boletus bicolor that inhibits the proliferation of NSCLC cell lines. In this study, we elucidated the internalization mechanism and antitumor mechanism of protein D1 in A549 cells. Protein D1 has a strong inhibitory effect on A549 cells. It binds to secretory carrier membrane protein 3 on the A549 cell membrane and enters A549 cells by clathrin-mediated endocytosis. In vitro, protein D1 activates mitogen-activated protein kinase (MAPK) signaling pathway. JNK and p38MAPK are the biological targets for protein D1. In vivo, protein D1 inhibits the tumor growth of NSCLC xenografts by inducing apoptosis and inhibiting cell proliferation. Protein D1 alters the expression of genes related to apoptosis, cell cycle, and MAPK signaling pathway in tumor cells.

Effect of Different Cooking Methods on Nutrients, Antioxidant Activities and Flavors of Three Varieties of Lentinus edodes

This work evaluated the effect of different cooking methods (boiling, steaming, microwaving, frying and pressure cooking) on the nutrients, antioxidant activities, volatile and nonvolatile taste-active components of three varieties of Lentinus edodes (808, 0912 and LM) from Guizhou Province. The results showed that LM had the most polysaccharides, 0912 had the most minerals, but LM, 808 and 0912 had low amounts of polyphenols, dietary fiber and proteins, respectively. The dietary fiber and protein were decreased by 4.1~38.7% and 4.1~44.0% during cooking, while microwaving improved the nutritional value of the Lentinus edodes by increasing the polysaccharide (88~103 mg/g to 93~105 mg/g) and polyphenol content (6.4~8.1 mg/g to 7.5~11.2 mg/g), thereby strengthening the antioxidant activity. The nucleotides were all destroyed after cooking, especially frying or boiling. The glutamate content was the highest in LM and 808, and the methionine content appeared to be the highest in 0912. Pressure cooking and frying increased the proportions of sweet and umami amino acids and decreased the proportion of bitter amino acids, creating more aroma-active compounds. In summary, microwaving increased the content of bioactive compounds and antioxidant activities, and it preserved nonvolatile taste-active components, while pressure cooking and frying were the best methods for increasing the flavor compounds.