Alpinia katsumadai Hayata induces growth inhibition and autophagy­related apoptosis by regulating the AMPK and Akt/mTOR/p70S6K signaling pathways in cancer cells.

Alpinia katsumadai Hayata (AKH), a widely used traditional Chinese medicine, exerts various biological functions, including anti­inflammatory, antioxidant, anti­microbial and anti­asthmatic effects. However, studies on its anticancer activity and associated mechanisms are limited. The present study investigated the effects of ethanol extract from AKH on the viability of various human cancer and normal liver LX­2 cells using Cell Counting Kit­8 assay. Apoptosis was detected by Hoechst 33342/PI staining and Annexin­V­FITC/PI double staining. Autophagy was examined by Ad­GFP­LC3B transfection. The association between AKH­induced autophagy and apoptosis was investigated by pre­treatment of the cells with the autophagy inhibitors, 3­methyladenine (3MA) and bafilomycin A1 (Baf­A1), followed by treatment with AKH. The expression levels of cleaved poly(ADP­ribose) polymerase (PARP), caspase­8, caspase­3, caspase­9, phosphorylated (p­)AMP­activated protein kinase (AMPK), Akt, mTOR and p70S6K were examined using western blot analysis. The in vivo antitumor activity of AKH was investigated in nude mice bearing A549 lung cancer xenografts. The components of AKH were detected by liquid chromatography mass spectrometry­ion trap­time­of­flight mass spectrometry. The results revealed that AKH significantly inhibited the proliferation of various cancer cells with the half maximal inhibitory concentration (IC50) values of 203­284 µg/ml; however, its inhibitory effect was much less prominent against normal liver LX­2 cells with an IC50 value of 395 µg/ml. AKH markedly induced apoptosis and autophagy, and upregulated the protein expression of cleaved­caspase­3, caspase­8, caspase­9 and cleaved PARP in a concentration­dependent manner. Of note, the autophagy inhibitors (3MA and Baf­A1) significantly attenuated its pro­apoptotic effects on human pancreatic cancer Panc­28 and lung cancer A549 cells. Furthermore, AKH significantly increased the levels of p­AMPK, and decreased those of p­Akt, p­mTOR and p­p70S6K in Panc­28 and A549 cells. AKH markedly inhibited the growth of A549 tumor xenografts in vivo. In addition, a total of nine compounds were detected from AKH. The present study demonstrates that AKH markedly inhibits the growth and induces autophagy­related apoptosis in cancer cells by regulating the AMPK and Akt/mTOR/p70S6K signaling pathways. AKH and/or its active fractions may thus have potential to be developed as novel anticancer agents for clinical use.

Alpinetin: A Review of Its Pharmacology and Pharmacokinetics.

Flavonoids isolated from medicinal herbs have been utilized as valuable health-care agents due to their virous biological applications. Alpinetin is a natural flavonoid that emerges in many widely used medicinal plants, and has been frequently applied in Chinese patent drugs. Accumulated evidence has demonstrated that alpinetin possesses a broad range of pharmacological activities such as antitumor, antiinflammation, hepatoprotective, cardiovascular protective, lung protective, antibacterial, antiviral, neuroprotective, and other properties through regulating multiple signaling pathways with low systemic toxicity. However, pharmacokinetic studies have documented that alpinetin may have poor oral bioavailability correlated to its extensive glucuronidation. Currently, the reported pharmacological properties and pharmacokinetics profiles of alpinetin are rare to be scientifically reviewed. In this article, we aimed to highlight the mechanisms of action of alpinetin in various diseases to strongly support its curative potentials for prospective clinical applications. We also summarized the pharmacokinetics properties and proposed some viable strategies to convey an appreciable reference for future advances of alpinetin in drug development.

Apoptotic Pathway as the Therapeutic Target for Anticancer Traditional Chinese Medicines.

Cancer is a leading cause of morbidity and mortality worldwide. Apoptosis is a process of programmed cell death and it plays a vital role in human development and tissue homeostasis. Mounting evidence indicates that apoptosis is closely related to the survival of cancer and it has emerged as a key target for the discovery and development of novel anticancer drugs. Various studies indicate that targeting the apoptotic signaling pathway by anticancer drugs is an important mechanism in cancer therapy. Therefore, numerous novel anticancer agents have been discovered and developed from traditional Chinese medicines (TCMs) by targeting the cellular apoptotic pathway of cancer cells and shown clinically beneficial effects in cancer therapy. This review aims to provide a comprehensive discussion for the role, pharmacology, related biology, and possible mechanism(s) of a number of important anticancer TCMs and their derivatives mainly targeting the cellular apoptotic pathway. It may have important clinical implications in cancer therapy.

Active fraction of clove induces apoptosis via PI3K/Akt/mTOR-mediated autophagy in human colorectal cancer HCT-116 cells.

Previous studies by our group have demonstrated that extract of clove exhibits potent anticancer effects in vitro and in vivo. In the present study, the effect of an extracted and isolated active fraction of clove (AFC) on induction of cellular apoptosis in human colorectal cancer HCT-116 cells was investigated by morphological observation, flow cytometry, and western blotting analysis. The results revealed that AFC induced apoptosis of HCT-116 cells. AFC also induced autophagy, demonstrated by increased punctuate microtubule-associated protein 1A/1B-light chain 3 (LC3) staining, and LC3-II and Beclin-1 protein expression levels. Furthermore, the autophagy inhibitors 3-MA and baflomycin A1 potentiated the pro-apoptotic activity of AFC in HCT-116 cells. AFC also inhibited the phosphorylation of the phosphoinositide 3-kinase/Akt/mechanistic target of rapamycin signaling pathway. The present study may improve the existing understanding of the anticancer mechanisms of clove and provide a scientific rationale for AFC to be further developed as a promising novel anticancer agent for the treatment of colorectal cancer.