Glaucocalyxin A induces apoptosis and autophagy in tongue squamous cell carcinoma cells by regulating ROS

Autophagy in oral cancer: Promises and challenges (Review)

Autophagy captures damaged or dysfunctional proteins and organelles through the lysosomal pathway to achieve proper cellular homeostasis. Autophagy possesses distinct characteristics and is given recognized functions in numerous physiological and pathological conditions, such as cancer. Early stage cancer development can be stopped by autophagy. After tumor cells have successfully undergone transformation and progressed to a late stage, the autophagy-mediated system of dynamic degradation and recycling will support cancer cell growth and adaptation to various cellular stress responses while preserving energy homeostasis. In the present study, the dual function that autophagy plays in various oral cancer development contexts and stages, the existing arguments for and against autophagy, and the ways in which autophagy contributes to oral cancer modifications, such as carcinogenesis, drug resistance, invasion, metastasis and self-proliferation, are reviewed. Special attention is paid to the mechanisms and functions of autophagy in oral cancer processes, and the most recent findings on the application of certain conventional drugs or natural compounds as novel agents that modulate autophagy in oral cancer are discussed. Overall, further research is needed to determine the validity and reliability of autophagy promotion and inhibition while maximizing the difficult challenge of increasing cancer suppression to improve clinical outcomes.

Identification and validation of autophagy-related genes influenced by paris polyphylla in tongue cancer using network pharmacology

BACKGROUND

Tongue squamous cell carcinoma (TSCC) represents the most prevalent form of head and neck squamous cell carcinomas, comprising approximately one-third of all oral cancers. Paris polyphylla(PP) exhibit promising anti-tumor properties, yet their underlying mechanisms remain elusive. This study offers novel insights into the molecular mechanisms underlying TSCC treatment with PP and establishes a theoretical basis for their clinical application.

METHODS

Employing transcriptomics and network pharmacology methodologies, we identified autophagy-related key genes associated with the effects of PP. These genes were subjected to KEGG and GO enrichment analyses to determine their related functions. In vitro, CAL-27 cells were treated with 10, 30, and 60 μg/ml of PP for 24 h to assess tumor cell proliferation, apoptosis, and autophagy-related markers.

KEY FINDINGS

Molecular docking of MAPK3 and PSEN1 with PP revealed stable hydrogen bond interactions, indicating the therapeutic potential of these saponins in TSCC through the autophagy pathway. In vitro experiments demonstrated significant inhibition of proliferative activity in tongue squamous carcinoma CAL-27 cells and promotion of tumor cell apoptosis by PP. Western blot analysis confirmed alterations in the expression of autophagy markers P62, LC3B, and Beclin1 following treatment, suggesting activation of the autophagy pathway.

CONCLUSIONS

Our results suggest that PP inhibits tumor cells through the autophagy pathway, in which MAPK3 and PSEN1 play a role as potential functional molecules.

Chemoproteomics Reveals Glaucocalyxin A Induces Mitochondria-Dependent Apoptosis of Leukemia Cells via Covalently Binding to VDAC1

Chronic myelogenous leukemia (CML) that is resistant to tyrosine kinase inhibitors is one of the deadliest hematologic malignancies, and the T315I mutation in the breakpoint cluster region-Abelson (BCR-ABL) kinase domain is the most prominent point mutation responsible for imatinib resistance in CML. Glaucocalyxin A (GLA), a natural bioactive product derived from the Rabdosia rubescens plant, has strong anticancer activity. In this study, the effect and molecular mechanism of GLA on imatinib-sensitive and imatinib-resistant CML cells harboring T315I mutation via a combined deconvolution strategy of chemoproteomics and label-free proteomics is investigated. The data demonstrated that GLA restrains proliferation and induces mitochondria-dependent apoptosis in both imatinib-sensitive and resistant CML cells. GLA covalently binds to the cysteine residues of mitochondrial voltage-dependent anion channels (VDACs), resulting in mitochondrial damage and overflow of intracellular apoptotic factors, eventually leading to apoptosis. In addition, the combination of GLA with elastin, a mitochondrial channel VDAC2/3 inhibitor, enhances mitochondria-dependent apoptosis in imatinib-sensitive and -resistant CML cells, representing a promising therapeutic approach for leukemia treatment. Taken together, the results show that GLA induces mitochondria-dependent apoptosis via covalently targeting VDACs in CML cells. GLA may thus be a candidate compound for the treatment of leukemia.

Glaucocalyxin A Inhibits the Malignancies of Gastric Cancer Cells by Downregulating MDM2 and RNF6 via MiR-3658 and the SMG1-UPF mRNA Decay Pathway

Gastric cancer (GC) ranks as the most common gastrointestinal cancer and is among the leading causes of cancer death worldwide. Glaucocalyxin A (GLA), an entkauranoid diterpene isolated from Rab-dosia japonica var., possesses various bioactivities. To date, the data on the effect of GLA on GC are still minimal, and the molecular mechanisms remain largely unknown. Herein, we found that GLA could significantly inhibit the proliferation, cell adhesion, and invasion of HGT-1, SNU-1, SNU-6, and NCI-N87 GC cells in a dose-dependent manner. GLA enhanced the apoptosis of the GC cells as evidenced by the increased caspase-3 activity and the elevated levels of cleaved caspase-3 and cleaved PARP in GC cells in the presence of GLA. We then showed that the downregulation of Murine Double Minute Clone 2 (MDM2) and Ring Finger Protein 6 (RNF6) by GLA was implicated in the GLA-induced inhibition of the GC cells. Furthermore, MDM2 and RNF6 were identified as the targets of miR-3658 that was downregulated in the GC cells and upregulated by GLA. Moreover, it was shown that miR-3658 was hypermethylated in the GC cells, and GLA could rescue the expression of miR-3658 via demethylation by abrogating EZH2-mediated epigenetic silencing. In addition to the miR-3658-MDM2/RNF6 regulatory axis, activation of the SMG1-UPF mRNA decay pathway contributed to the downregulation of MDM2 and RNF6 by GLA in the GC cells. The inhibitory effect of GLA on gastric cancer and the expression of MDM2 and RNF6 was also validated in in vivo study. Our findings suggest that has the therapeutic potential for GC by downregulating oncogenes via posttranscriptional regulation.

Dihydroartemisinin Induces ER Stress-Mediated Apoptosis in Human Tongue Squamous Carcinoma by Regulating ROS Production

BACKGROUND

Tongue squamous cell carcinoma is a fatal disease characterized by high invasion and early metastasis. Dihydroartemisinin, an antimalarial drug with multiple biological activities, is reported to be a potential anti-cancer agent.

OBJECTIVE

This study aimed to evaluate the antitumor effect of Dihydroartemisinin on tongue squamous cell carcinoma cells, and to identify the underlying mechanisms of Dihydroartemisinin-induced cell apoptosis.

METHODS

Here, Cell Counting Kit 8 assay and colony formation assay were conducted to study cell proliferation. Annexin V-FITC/propidium iodide staining and western blot analysis were performed to analyze cell apoptosis. DCFH-DA probe was used to measure the generation of cellular reactive oxygen species. Endoplasmic reticulum stress activation was also determined via western blot analysis.

RESULTS

The results showed that Dihydroartemisinin substantially inhibited cell proliferation and induced cell apoptosis in vivo. Moreover, reactive oxygen species production and endoplasmic reticulum stress activation were both observed after stimulation with Dihydroartemisinin. However, the reactive oxygen species inhibitor N-acetylcysteine significantly alleviated Dihydroartemisinin-induced endoplasmic reticulum stress and apoptosis.

CONCLUSION

These results imply that Dihydroartemisinin induced cell apoptosis by triggering reactive oxygen species-mediated endoplasmic reticulum stress in CAL27 cells. In addition, Dihydroartemisinin might be an effective drug for tongue squamous cell carcinoma therapy.