Pomiferin targets SERCA, mTOR, and P-gp to induce autophagic cell death in apoptosis-resistant cancer cells, and reverses the MDR phenotype in cisplatin-resistant tumors in vivo.

Drug resistance in cancer has been classified as innate resistance or acquired resistance, which were characterized by apoptotic defects and ABC transporters overexpression respectively. Therefore, to preclude or reverse these resistance mechanisms could be a promising strategy to improve chemotherapeutic outcomes. In this study, a natural product from Osage Orange, pomiferin, was identified as a novel autophagy activator that circumvents innate resistance by triggering autophagic cell death via SERCA inhibition and activation of the CaMKKβ-AMPK-mTOR signaling cascade.

SERCA and P-glycoprotein inhibition and ATP depletion are necessary for celastrol-induced autophagic cell death and collateral sensitivity in multidrug-resistant tumor cells.

Multidrug resistance (MDR) represents an obstacle in anti-cancer therapy. MDR is caused by multiple mechanisms, involving ATP-binding cassette (ABC) transporters such as P-glycoprotein (P-gp), which reduces intracellular drug levels to sub-therapeutic concentrations. Therefore, sensitizing agents retaining effectiveness against apoptosis- or drug-resistant cancers are desired for the treatment of MDR cancers.

Neferine induces autophagy-dependent cell death in apoptosis-resistant cancers via ryanodine receptor and Ca-dependent mechanism.

Resistance of cancer cells to chemotherapy is a significant clinical concern and mechanisms regulating cell death in cancer therapy, including apoptosis, autophagy or necrosis, have been extensively investigated over the last decade. Accordingly, the identification of medicinal compounds against chemoresistant cancer cells via new mechanism of action is highly desired. Autophagy is important in inducing cell death or survival in cancer therapy.

Ca signalling plays a role in celastrol-mediated suppression of synovial fibroblasts of rheumatoid arthritis patients and experimental arthritis in rats.

Background And Purpose: Celastrol exhibits anti-arthritic effects in rheumatoid arthritis (RA), but the role of celastrol-mediated Ca mobilization in treatment of RA remains undefined. Here, we describe a regulatory role for celastrol-induced Ca signalling in synovial fibroblasts of RA patients and adjuvant-induced arthritis (AIA) in rats.

Experimental Approach: We used computational docking, Ca dynamics and functional assays to study the sarcoplasmic/endoplasmic reticulum Ca ATPase pump (SERCA).

-Desmethyldauricine Induces Autophagic Cell Death in Apoptosis-Defective Cells via Ca Mobilization.

Resistance of cancer cells to chemotherapy remains a significant problem in oncology. Mechanisms regulating programmed cell death, including apoptosis, autophagy or necrosis, in the treatment of cancers have been extensively investigated over the last few decades. Autophagy is now emerging as an important pathway in regulating cell death or survival in cancer therapy.

Mode of Action Analyses of Neferine, a Bisbenzylisoquinoline Alkaloid of Lotus () against Multidrug-Resistant Tumor Cells.

Neferine, a bisbenzylisoquinoline alkaloid isolated from the green seed embryos of Lotus ( Gaertn), has been previously shown to have various anti-cancer effects. In the present study, we evaluated the effect of neferine in terms of P-glycoprotein (P-gp) inhibition via cytotoxicity assays, R123 uptake assays in drug-resistant cancer cells, molecular docking analysis on human P-gp and absorption, distribution, metabolism, and excretion (ADME), quantitative structure activity relationships (QSAR) and toxicity analyses. Lipinski rule of five were mainly considered for the ADME evaluation and the preset descriptors including number of hydrogen bond donor, acceptor, hERG IC, logp, logD were considered for the QSAR analyses.

Thalidezine, a novel AMPK activator, eliminates apoptosis-resistant cancer cells through energy-mediated autophagic cell death.

Cancers illustrating resistance towards apoptosis is one of the main factors causing clinical failure of conventional chemotherapy. Innovative therapeutic methods which can overcome the non-apoptotic phenotype are needed. The AMP-activated protein kinase (AMPK) is the central regulator of cellular energy homeostasis, metabolism, and autophagy.

Autophagic degradation of epidermal growth factor receptor in gefitinib-resistant lung cancer by celastrol.

Drug resistance of non-small cell lung cancer (NSCLC) is highly correlated to the mutation of the epidermal growth factor receptor (EGFR). Although EGFR tyrosine kinase inhibitors (TKIs) are available clinically, the molecular complexity of NSCLC has made it necessary to search for alternative therapeutic approaches to overcome the drug resistance of NSCLC. In the present study, we identified a triterpene molecule derived from the herbal plant Tripterygium wilfordii, celastrol, as a novel autophagy inducer.

Advanced research technology for discovery of new effective compounds from Chinese herbal medicine and their molecular targets.

Traditional biotechnology has been utilized by human civilization for long in wide aspects of our daily life, such as wine and vinegar production, which can generate new phytochemicals from natural products using micro-organism. Today, with advanced biotechnology, diverse applications and advantages have been exhibited not only in bringing benefits to increase the diversity and composition of herbal phytochemicals, but also helping to elucidate the treatment mechanism and accelerate new drug discovery from Chinese herbal medicine (CHM). Applications on phytochemical biotechnologies and microbial biotechnologies have been promoted to enhance phytochemical diversity.

Hernandezine, a novel AMPK activator induces autophagic cell death in drug-resistant cancers.

Drug resistance hinder most cancer chemotherapies and leads to disease recurrence and poor survival of patients. Resistance of cancer cells towards apoptosis is the major cause of these symptomatic behaviours. Here, we showed that isoquinoline alkaloids, including liensinine, isoliensinine, dauricine, cepharanthine and hernandezine, putatively induce cytotoxicity against a repertoire of cancer cell lines (HeLa, A549, MCF-7, PC3, HepG2, Hep3B and H1299).

(Z)3,4,5,4'-trans-tetramethoxystilbene, a new analogue of resveratrol, inhibits gefitinb-resistant non-small cell lung cancer via selectively elevating intracellular calcium level.

Calcium is a second messenger which is required for regulation of many cellular processes. However, excessive elevation or prolonged activation of calcium signaling would lead to cell death. As such, selectively regulating calcium signaling could be an alternative approach for anti-cancer therapy.

Natural small-molecule enhancers of autophagy induce autophagic cell death in apoptosis-defective cells.

Resistance of cancer cells to chemotherapy is a significant problem in oncology, and the development of sensitising agents or small-molecules with new mechanisms of action to kill these cells is needed. Autophagy is a cellular process responsible for the turnover of misfolded proteins or damaged organelles, and it also recycles nutrients to maintain energy levels for cell survival. In some apoptosis-resistant cancer cells, autophagy can also enhance the efficacy of anti-cancer drugs through autophagy-mediated mechanisms of cell death.

Onjisaponin B derived from Radix Polygalae enhances autophagy and accelerates the degradation of mutant α-synuclein and huntingtin in PC-12 cells.

Emerging evidence indicates important protective roles being played by autophagy in neurodegenerative disorders through clearance of aggregate-prone or mutant proteins. In the current study, we aimed to identify autophagy inducers from Chinese medicinal herbs as a potential neuroprotective agent that enhances the clearance of mutant huntingtin and α-synuclein in PC-12 cells. Through intensive screening using the green fluorescent protein-light chain 3 (GFP-LC3) autophagy detection platform, we found that the ethanol extracts of Radix Polygalae (Yuan Zhi) were capable of inducing autophagy.