Corynoxine suppresses pancreatic cancer growth primarily via ROS-p38 mediated cytostatic effects

The beneficial pharmacological effects of Uncaria rhynchophylla in neurodegenerative diseases: focus on alkaloids

With the intensification of aging population, the prevention or treatment of neurodegenerative diseases, such as Parkinson's disease and Alzheimer's disease, has drawn more and more attention. As a long used traditional Chinese medicine, Uncaria rhynchophylla (Miq.) Jacks., named Gouteng in Chinese, has been reported to have an effective neuroprotective role in neurodegenerative diseases. In this review, the beneficial pharmacological effects and signaling pathways of herbal formulas containing U. rhynchophylla, especially major compounds identified from U. rhynchophylla, such as corynoxine B, corynoxine, rhynchophylline, and isorhynchophylline, in neurodegenerative diseases, were summarized, which not only provide an overview of U. rhynchophylla for the prevention or treatment of neurodegenerative diseases but also give some perspective to the development of new drugs from traditional Chinese medicine.

Phytochemical-mediated modulation of autophagy and endoplasmic reticulum stress as a cancer therapeutic approach

Autophagy and endoplasmic reticulum (ER) stress are conserved processes that generally promote survival, but can induce cell death when physiological thresholds are crossed. The pro-survival aspects of these processes are exploited by cancer cells for tumor development and progression. Therefore, anticancer drugs targeting autophagy or ER stress to induce cell death and/or block the pro-survival aspects are being investigated extensively. Consistently, several phytochemicals have been reported to exert their anticancer effects by modulating autophagy and/or ER stress. Various phytochemicals (e.g., celastrol, curcumin, emodin, resveratrol, among others) activate the unfolded protein response to induce ER stress-mediated apoptosis through different pathways. Similarly, various phytochemicals induce autophagy through different mechanisms (namely mechanistic target of Rapamycin [mTOR] inhibition). However, phytochemical-induced autophagy can function either as a cytoprotective mechanism or as programmed cell death type II. Interestingly, at times, the same phytochemical (e.g., 6-gingerol, emodin, shikonin, among others) can induce cytoprotective autophagy or programmed cell death type II depending on cellular contexts, such as cancer type. Although there is well-documented mechanistic interplay between autophagy and ER stress, only a one-way modulation was noted with some phytochemicals (carnosol, capsaicin, cryptotanshinone, guangsangon E, kaempferol, and δ-tocotrienol): ER stress-dependent autophagy. Plant extracts are sources of potent phytochemicals and while numerous phytochemicals have been investigated in preclinical and clinical studies, the search for novel phytochemicals with anticancer effects is ongoing from plant extracts used in traditional medicine (e.g., Origanum majorana). Nonetheless, the clinical translation of phytochemicals, a promising avenue for cancer therapeutics, is hindered by several limitations that need to be addressed in future studies.

Corynoxine triggers cell death via activating PP2A and regulating AKT-mTOR/GSK3β axes in NSCLC

This study investigates the anticancer activity and pharmacological mechanisms of Corynoxine (Cory) in non-small cell lung cancer (NSCLC). Cory, a natural product derived from the Chinese herbal medicine Uncaria rhynchophylla, demonstrates promising pharmacological activity. Cell proliferation and viability were evaluated via MTT and colony formation assays. Flow cytometry was employed to analyze cell apoptosis, cycle distribution, and mitochondrial membrane potential. Autophagy was detected using fluorescence microscopy and electron microscopy. Western blotting, protein overexpression, gene knockdown, co-immunoprecipitation, and bioinformatics characterized Cory's impact on signaling pathways. The research indicates that Cory inhibits the proliferation of NSCLC cells in vivo and in vitro. Cory enhances PP2A activity, inhibits the AKT/mTOR signaling pathway triggering autophagy, while suppressing the AKT/GSK3β signaling pathway to induce cellular apoptosis in NSCLC. Notably, the activation of PP2A plays a crucial role in Cory's antitumor effects by inhibiting AKT. In vivo experiments validated Cory's efficacy in NSCLC treatment. These findings highlight the promising role of Cory as a lead compound for drug development in NSCLC therapy, providing a viable option for addressing this challenging disease.

Suppressing MTERF3 inhibits proliferation of human hepatocellular carcinoma via ROS-mediated p38 MAPK activation

Mitochondrial transcription termination factor 3 (MTERF3) negatively regulates mitochondrial DNA transcription. However, its role in hepatocellular carcinoma (HCC) progression remains elusive. Here, we investigate the expression and function of MTERF3 in HCC. MTERF3 is overexpressed in HCC tumor tissues and higher expression of MTERF3 positively correlates with poor overall survival of HCC patients. Knockdown of MTERF3 induces mitochondrial dysfunction, S-G2/M cell cycle arrest and apoptosis, resulting in cell proliferation inhibition. In contrast, overexpression of MTERF3 promotes cell cycle progression and cell proliferation. Mechanistically, mitochondrial dysfunction induced by MTERF3 knockdown promotes ROS accumulation, activating p38 MAPK signaling pathway to suppress HCC cell proliferation. In conclusion, ROS accumulation induced by MTERF3 knockdown inhibits HCC cell proliferation via p38 MAPK signaling pathway suggesting a promising target in HCC patients.