Ganoderic acid A holds promising cytotoxicity on human glioblastoma mediated by incurring apoptosis and autophagy and inactivating PI3K/AKT signaling pathway.

Ganoderic acid A (GA-A), recognized as a lanostanetriterpene isolated from Ganoderma lucidum, demonstrates an efficient antitumor activity in multiple cancers. To date, it is unclear whether and how GA-A functions on human glioblastoma (GBM). To unravel the functional significance of GA-A on human glioblastoma (GBM), the cell-counting kit-8 and transwell assays were used to detect proliferation, migration, and invasion of human GBM cell after GA-A treatment. Then, we utilized the flow cytometry and western blot to further evaluate the effect of GA-A on GBM cell. Further, activities of autophagy and PI3K/AKT signaling were assessed by Western blot assay. We found that GA-A significantly inhibited proliferation, migration, and invasion of GBM cell. Additionally, GA-A markedly triggered cell apoptosis, which incarnated an elevation trend in apoptotic percentage, simultaneously, an increased level of proapoptosis protein (Bax and active caspase-3) and a decreased level of antiapoptosis protein (Bcl-2), induced by GA-A treatment. Meanwhile, levels of two well-known autophagy markers (beclin 1 and LC3 II) increased while another autophagic substrate (P-62) was reduced. Moreover, the expressions levels of phosphorylated AKT, mTOR, p-P70S6K, and cyclin D1 in the PI3K/AKT pathway were significantly reduced, which revealed GA-A repressed the activation of PI3K/AKT signaling pathway. Collectively, these results indicate that GA-A may encourage U251 cell growth and invasion/migration inhibition, apoptosis, and autophagy through the inactivation of PI3K/AKT signaling pathway in human GBM. Hence, GA-A may be a potent antitumorigenic agent for human GBM in future clinical practice.

Cheng Y ，Xie P 《-》

Ganoderic acid A alleviates hypoxia-induced apoptosis, autophagy, and inflammation in rat neural stem cells through the PI3K/AKT/mTOR pathways.

Effects of ganoderic acid A (GAA), a lanostane triterpene, on hypoxia-ischemia encephalopathy (HIE) remain unclear. We aimed to figure out the specific role of GAA in hypoxia-treated neural stem cells (NSCs) as well as the regulatory mechanisms. Primary rat NSCs were incubated under hypoxia to simulate HIE. Viability and apoptosis of hypoxia-injured NSCs were measured by cell counting kit-8 and flow cytometry assays, respectively. Proteins related to apoptosis, autophagy, and the PI3K/AKT/mTOR pathways were evaluated by Western blot analysis. LY294002 and rapamycin were added to inhibit the PI3K/AKT pathway and mTOR pathway, respectively. Enzyme-linked immunosorbent assay was carried out to test the release of proinflammatory cytokines. We found that hypoxia-induced decrease of cell viability, increases of apoptotic cells and autophagy, and the release of IL-6, IL-1β, and TNF-α were all attenuated by GAA stimulation. Activation of caspases induced by hypoxia was alleviated by GAA. Furthermore, we found that inhibition of the PI3K/AKT pathway eliminated the effects of GAA on apoptosis and proinflammatory cytokines release in hypoxia-injured NSCs. Meanwhile, inhibition of the mTOR pathway abrogated the effects of GAA on cell autophagy in hypoxia-injured NSCs. In conclusion, GAA alleviated hypoxia-induced injury in NSCs might be through activating the PI3K/AKT and mTOR pathways.

Chang Y ，Kong R 《-》

Ganoderic acid DM induces autophagic apoptosis in non-small cell lung cancer cells by inhibiting the PI3K/Akt/mTOR activity.

The incidence and mortality of lung cancer are the highest among cancer-related deaths. However, the long-term use of currently available cytotoxic drugs can increase genetic alterations in cancer cells and cause drug-resistance, which significantly limits their usage. Since current systemic treatment options are limited, effective chemotherapeutic agents are urgently needed for non-small cell lung cancer (NSCLC) treatment. In this study, we demonstrated that ganoderic acid DM (GA-DM) could increase apoptosis in A549 and NCI-H460 NSCLC cells. GA-DM treatment decreased the protein expression levels of Bcl-2 and increased the expression levels of Bax, cleaved caspase-3 and cleaved PRAP. Furthermore, GA-DM could promote autophagic flux, and the cytotoxic effect against cancer cells of GA-DM was significantly inhibited by targeted suppression of autophagy, suggesting that autophagy contributed to GA-DM-induced cell death in NSCLC. Moreover, GA-DM clearly induced autophagy by inactivating the PI3K/Akt/mTOR pathway. When overexpression of Akt reactivated Akt/mTOR pathway in A549 or NCI-H460 cells, the increase of autophagy related marker LC3B-II and apoptosis related protein cleaved PARP and cleaved caspase 3 and the ration of apoptotic cells by GA-DM was reversed, suggesting that GA-DM promoted autophagy and apoptosis by inhibiting Akt/mTOR pathway-mediated autophagy induction. In conclusion, our study indicated that GA-DM can induce autophagic apoptosis in NSCLC by inhibiting Akt/mTOR activity. (209 words).

Xia J ，Dai L ，Wang L ，Zhu J ... -  《-》

Polyphyllin I Promoted Melanoma Cells Autophagy and Apoptosis via PI3K/Akt/mTOR Signaling Pathway.

To investigate whether Polyphyllin I (PPI) might induce the autophagy and apoptosis of melanoma cells by regulating PI3K/Akt/mTOR signal pathway. Melanoma A375 cells were incubated with different concentrations of Polyphyllin I (0, 1.5, 3.0, and 6.0 mg/L) and PI3K/Akt/mTOR signaling pathway activator IGF-1(20 mg/L). CCK-8 assay was utilized to detect cell proliferation; Cell apoptosis and cell cycle were measured by flow cytometry; Western blot was used to examine the expressions of proteins. Immunofluorescence analysis was performed to evaluate autophagy of A375 cells; In addition, xenograft-bearing nude mice were applied to study the role of Polyphyllin I on melanoma development, melanoma cell proliferation, as well as melanoma cell apoptosis in vivo. The outcomes represented that Polyphyllin I promoted A375 cell apoptosis via upregulating Bax level and cleaved caspase-3 level and downregulating Bcl-2 level, inhibited the growth of A375 cells at the G0/G1 phase, and enhanced cell autophagy via regulating the levels of Beclin 1, LC3II, and p62. However, IGF-1 (an activator of PI3K/Akt/mTOR signal pathway) attenuated these changes that Polyphyllin I induced. Furthermore, the xenograft model experiment confirmed that Polyphyllin I treatment suppressed xenograft tumor growth, increased apoptotic index evaluated by the TUNEL method, and reduced the level of Ki67 in tumor tissues in vivo. In conclusion, Polyphyllin I treatment enhanced melanoma cell autophagy and apoptosis, as well as blocked melanoma cell cycle via suppressing PI3K/Akt/mTOR signal pathway. Meanwhile, Polyphyllin I treatment suppressed the development of melanoma in vivo. Therefore, Polyphyllin I possibly is a promising molecular targeted agent used in melanoma therapy.

Long J ，Pi X 《-》

Isoliquiritigenin inhibits proliferation and metastasis of MKN28 gastric cancer cells by suppressing the PI3K/AKT/mTOR signaling pathway.

Zhang XR ，Wang SY ，Sun W ，Wei C ... -  《-》