Grape seed proanthocyanidins induce apoptosis through the mitochondrial pathway in nasopharyngeal carcinoma CNE-2 cells

Condensed tannins from Salix babylonica L. leaves induce apoptosis of human ovarian cancer cells through mitochondrial and PI3K/AKT/ERK signaling pathways

Condensed tannins, natural antioxidants, are widely known for their antitumor activity with low toxicity. However, the antitumor mechanism of Salix babylonica leaf condensed tannins (SCTs) remains unclear. Here, we purified bioactive SCTs and analyzed their structural characteristics, antitumor effects on human ovarian cancer (OC) cells as well as related potential mechanism. FT-IR, ESI-MS, and HPLC analyses demonstrated that SCTs primarily consist of procyanidins with (epi)catechin as the main flavan-3-ol extension unit. SCTs significantly inhibited the proliferation and migration of OVCAR3 and A2780 cells, induced G0/G1 cell cycle arrest, and promoted apoptosis. SCTs induced apoptosis through the mitochondrial apoptotic pathway by decreasing mitochondrial membrane potential, increasing intracellular reactive oxygen species generation, elevating the Bax/Bcl-2 ratio, and activating caspase-3. Network pharmacology analysis speculated that SCTs exert anti-ovarian cancer effects by targeting multiple targets and pathways, among which the PI3K/AKT/ERK pathway may be the main pathway of action. Western blot confirmed that SCTs inhibited the phosphorylation of AKT, MEK, and ERK. Moreover, SCTs dose-dependently impaired OVCAR3 tumor spheroid growth in three-dimensional culture models. These results suggested that SCTs induced apoptosis in OC cells by activating the mitochondrial-associated apoptosis pathway and inhibiting the PI3K/AKT/ERK signaling pathway, showing potential as therapeutic agents for OC.

Integrated network pharmacology, molecular docking and experimental validation to investigate the mechanism of tannic acid in nasopharyngeal cancer

Tannic acid (TA) is the primary bioactive component in the gallnut (Galla chinensis) and has exhibited the anticancer effects. However, the mechanism of its anti-cancer activity in nasopharyngeal carcinoma (NPC) remains unclear. This research aims to explore the underlying mechanism of TA in the treatment of nasopharyngeal cancer using network pharmacology, molecular docking and experimental validation. Firstly, the targets of TA and NPC were predicted and collected through databases, and the intersection targets were identified. Subsequently, protein-protein interaction (PPI) network analysis, Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes Genomes (KEGG) pathway enrichment analysis, molecular docking and molecular dynamics (MD) simulation were conducted to uncover the potential mechanisms of TA in treatment of NPC. Finally, in vitro experiments were utilized to verify the mechanism of TA with anticancer activity in NPC. The results of network pharmacology revealed 42 intersection targets between NPC-related targets and TA-related targets. The phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling was identified as the main target pathway of TA against NPC. Additionally, molecular docking and MD simulation confirmed the closely binding affinities of TA with AKT1. Furthermore, the results of in vitro experiments demonstrated that TA exerts anticancer activity against NPC by targeting the PI3K/AKT signaling pathway, leading to the suppression of cell proliferation. TA is a promising therapeutic candidate for NPC through PI3K/AKT signaling pathway. These results provide insights into the clinical application of TA, particularly when considered in combination with other therapeutic modalities.

The efficacy of natural products for the treatment of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumor originating in the nasopharyngeal epithelium with a high incidence in southern China and parts of Southeast Asia. The current treatment methods are mainly radiotherapy and chemotherapy. However, they often have side effects and are not suitable for long-term exposure. Natural products have received more and more attention in cancer prevention and treatment because of their its high efficiency, low toxic side effects, and low toxicity. Natural products can serve as a viable alternative, and this study aimed to review the efficacy and mechanisms of natural products in the treatment of NPC by examining previous literature. Most natural products act by inhibiting cell proliferation, metastasis, inducing cell cycle arrest, and apoptosis. Although further research is needed to verify their effectiveness and safety, natural products can significantly improve the treatment of NPC.

Grape seed proanthocyanidin extract induces apoptotic and autophagic cell death in rheumatoid arthritis fibroblast-like synoviocytes

Objectives

In this study, we aimed to evaluate the association between grape seed proanthocyanidin extract (GSPE) and rheumatoid arthritis-fibroblast-like synoviocytes (RA-FLSs) and to investigate whether GSPE induces cell death in RA-FLSs.

Materials and methods

The FLSs were isolated from RA synovial tissues. Cell viability and cell cycle staging were analyzed using a hemocytometer and flow cytometry. Caspase 3 and poly (ADP-ribose) polymerase (PARP) proteins were analyzed using Western blotting with z-VAD-fmk. Protein LC3 and polyubiquitin-binding protein p62 that were degraded by autophagy were evaluated using Western blotting with 3-methyladenine and chloroquine. Reactive oxygen species (ROS) were also evaluated.

Results

When RA-FLSs were treated with GSPE, cell viability decreased, the number of cells in sub-G1 and G2/M phases increased, and the expression of pro-PARP and pro-caspase 3 proteins decreased in a concentration-dependent manner. This result was offset, when the cells were co-treated with the pan-caspase inhibitor z-VAD-fmk. The reduced cell viability, increased expression of LC3-II protein, and reduced expression of p62 protein with GSPE treatment were offset, when RA-FLSs were co-treated with GSPE and autophagy inhibitors 3-methyladenine and chloroquine. The level of ROS in RA-FLSs treated with GSPE was significantly lower than treatment with N-acetyl-cysteine, a ROS inhibitor.

Conclusion

Our study results show that GSPE induces apoptotic and autophagic cell death and inhibites reactive oxygen species in RA-FLSs.

8-Formylophiopogonanone B induces ROS-mediated apoptosis in nasopharyngeal carcinoma CNE-1 cells

Cancer is one of the leading causes of death in the world. It is very important to find drugs with high efficiency, low toxicity, and low side effects for the treatment of cancer. Flavonoids and their derivatives with broad biological functions have been recognized as anti-tumor chemicals. 8-Formylophiopogonanone B (8-FOB), a naturally existed homoisoflavonoids with rarely known biological functions, needs pharmacological evaluation. In order to explore the possible anti-tumor action of 8-FOB, we used six types of tumor cells to evaluate in vitro effects of this agent on cell viability and tested the effects on clone formation ability, scratching wound-healing, and apoptosis. In an attempt to elucidate the mechanism of pharmacological action, we examined 8-FOB-induced intracellular oxidative stress and -disrupted mitochondrial function. Results suggested that 8-FOB could suppress tumor cell viability, inhibit cell migration and invasion, induce apoptosis, and elicit intracellular ROS production. Among these six types of tumor cells, the nasopharyngeal carcinoma CNE-1 cells were the most sensitive cancer cells to 8-FOB treatment. Intracellular ROS production played a pivotal role in the anti-tumor action of 8-FOB. Our present study is the first to document that 8-FOB has anti-tumor activity in vitro and increases intracellular ROS production, which might be responsible for its anti-tumor action. The anti-tumor pharmacological effect of 8-FOB is worthy of further investigation.

Targeting the signaling in Epstein-Barr virus-associated diseases: mechanism, regulation, and clinical study

Epstein–Barr virus-associated diseases are important global health concerns. As a group I carcinogen, EBV accounts for 1.5% of human malignances, including both epithelial- and lymphatic-originated tumors. Moreover, EBV plays an etiological and pathogenic role in a number of non-neoplastic diseases, and is even involved in multiple autoimmune diseases (SADs). In this review, we summarize and discuss some recent exciting discoveries in EBV research area, which including DNA methylation alterations, metabolic reprogramming, the changes of mitochondria and ubiquitin-proteasome system (UPS), oxidative stress and EBV lytic reactivation, variations in non-coding RNA (ncRNA), radiochemotherapy and immunotherapy. Understanding and learning from this advancement will further confirm the far-reaching and future value of therapeutic strategies in EBV-associated diseases.

Procyanidin Compound (PC) Suppresses Lipopolysaccharide-Induced Cervical Cancer Cell Proliferation Through Blocking the TLR4/NF-κB Pathway

Purpose

Evidence suggested that procyanidin compound (PC) could inhibit the progression of cervical cancer (CC); however, the mechanism still remains unclear. We aimed to study the potential mechanism of PC acting on CC cells.

Patients and Methods

After a 24 hr incubation of lipopolysaccharide (LPS) (1 μg/mL), human CC SiHa and HeLa cells were cultured with various concentrations (20, 40, and 80 μg/mL) of PC for 24 hrs, then the cell viability was detected using Cell Counting Kit-8 (CCK-8). The migration and invasion abilities were assessed by scratch and Transwell assays. Apoptosis and cell cycle were detected using flow cytometry. Real-time quantitative PCR (RT-qPCR) and Western blot were used for expression analysis of the inflammatory cytokines. The pathway components were measured to evaluate the involvement of toll-like receptor 4/nuclear factor kappa-light-chain-enhancer of activated B cells (TLR4/NF-κB) pathway.

Results

PC inhibited the LPS-primed cell viability in a dose-dependent manner. After PC treatment, cell migration and invasion were inhibited, cell number at the G2/M phase was increased. The CC cell apoptosis was triggered through upregulating levels of cleaved caspase-3 and Bax and downregulating the level of B-cell lymphoma 2 protein. A significant reduction was shown in the levels of interleukin (IL)-6, IL-1β and tumor necrosis factor (TNF)-α. Furthermore, a remarkable reduction in the ratio of TLR4 and the p-P65/t-P65 and in the progression of P65 translocation into the nucleus was observed.

Conclusion

Our results revealed that the inhibitory effect of PC on CC cell proliferation relies on the induction of apoptosis and inhibition of inflammatory cytokines.

Targeting vasculogenic mimicry by phytochemicals: A potential opportunity for cancer therapy

Vasculogenic mimicry (VM) is regarded as a process where very aggressive cancer cells generate vascular-like patterns without the presence of endothelial cells. It is considered as the main mark of malignant cancer and has pivotal role in cancer metastasis and progression in various types of cancers. On the other hand, resistance to the antiangiogenesis therapies leads to the cancer recurrence. Therefore, development of novel chemotherapies and their combinations is urgently needed for abolition of VM structures and also for better tumor therapy. Hence, identifying compounds that target VM structures might be superior therapeutic factors for cancers treatment and controlling the recurrence and metastasis. In recent times, naturally occurring compounds, especially phytochemicals have obtained great attention due to their safe properties. Phytochemicals are also capable of targeting VM structure and also their main signaling pathways. Consequently, in this review article, we illustrated key signaling pathways in VM, and the phytochemicals that affect these structures including curcumin, genistein, lycorine, luteolin, columbamine, triptolide, Paris polyphylla, dehydroeffusol, jatrorrhizine hydrochloride, grape seed proanthocyanidins, resveratrol, isoxanthohumol, dehydrocurvularine, galiellalactone, oxacyclododecindione, brucine, honokiol, ginsenoside Rg3, and norcantharidin. The recognition of these phytochemicals and their safety profile may lead to new therapeutic agents' development for VM elimination in different types of tumors.