Exploring the Mechanism of Realgar against Esophageal Cancer Based on Ferroptosis Induced by ROS-ASK1-p38 MAPK Signaling Pathway

Abstract

Background. Realgar (REA), a Chinese herbal decoction, has been used to treat various tumors and has produced positive outcomes; however, there is a lack of convincing evidence for the treatment of esophageal cancer. The present study aimed to investigate the effects of REA on esophageal cancer (EC) and explore its mechanism. Methods. EC cells Eca109 and KYSE150 were selected for this study, and different groups of treated cells were set up. We studied the inhibition rate and half inhibition concentration (IC50) by CCK-8 method, the clone formation assay was used to detect the clone formation ability, the scratch assay is used to determine the cell migration ability, the Transwell assay was used to detect the cell invasion ability, the protein expressions of E-cadherin, Slug, N-cadherin, ASK1, p38 MAPK, p-p38 MAPK, and GPX4 were determined using Western blot, the mRNA expressions of ASK1 and p38 MAPK were assessed using qRT-PCR, transmission electron microscopy was used to observe the cellular ultrastructure, Prussian blue staining was used to observe the intracellular iron particle distribution, and biochemical analysis of cellular MDA, SOD, GSH, and GPXS activities, flow cytometric analysis of cellular ROS levels, immunofluorescence staining to detect cellular GPX4 expression, and JC-1 method to detect mitochondrial membrane potential were used. Results. REA inhibited the proliferation of Eca109 and KYSE150 cells in a time- and concentration-dependent manner, and REA significantly inhibited the migration and invasion of Eca109 and KYSE150 cells and activated the cellular ferroptosis and ROS-ASK1-p38 MAPK signaling pathways ( P < 0.05 ). Inhibition of activation of the ROS-ASK1-p38 MAPK signaling pathway promoted the inhibition of proliferation, migration, and invasion of Eca109 and KYSE150 cells and the induction of ferroptosis by REA. Conclusion. REA induced ferroptosis and inhibited the migration of EC cells by activating the ROS-ASK1-p38 MAPK signaling pathway.

Realgar toxicity in terms of its chemical characterization, pharmacological mechanisms, and metabolic profile: A review

“…[32] Realgar also exhibits strong activity in inducing cell cycle arrest, [34] and interruption of realgar-induced G2/M progression is initiated through the activated Gadd45A/Cdc2/ cyclin B pathway, [33] leading to reduced migration and invasion of tumor cells. [36] Further investigations have revealed that realgar can inhibit the activation of the ROS-recombinant apoptosis signal regulating kinase 1-p38 mitogen-activated protein kinase signaling pathway [37] and decrease the expression of MMP-2 and MMP-9. [38] thus inhibiting the proliferation and neovascularization of tumor cells.…”

Unraveling the Complexity of Regulated Cell Death in Esophageal Cancer: from Underlying Mechanisms to Targeted Therapeutics

“…This finding suggests the potential of gliotoxin as a novel natural therapy for ESCC 232 . In addition, realgar (REA) , a Chinese herbal decoction, was found to not only decrease the proliferation, migration and invasion of KYSE150 and Eca109 cells but also promote ferroptosis by activating the ROS-ASK1-p38 MAPK signaling pathway 233 . Moreover, high expression of NRF2 protein in both primary tissues and EAC cell lines was detected by Ballout et al , and further studies showed that treatment with the NRF2 inhibitor brusatol alone or in combination with cisplatin induced ferroptosis of EAC cells by targeting NRF2; these results were evidenced by reduced expression of the ferroptosis markers GPX4 and xCT, which was confirmed in vivo 234 .…”