Dehydrocostus Lactone Induces Apoptosis and Cell Cycle Arrest through Regulation of JAK2/STAT3/PLK1 Signaling Pathway in Human Esophageal Squamous Cell Carcinoma Cells

Conjugates of 3,5-Bis(arylidene)-4-piperidone and Sesquiterpene Lactones Have an Antitumor Effect via Resetting the Metabolic Phenotype of Cancer Cells

In recent years, researchers have often encountered the significance of the aberrant metabolism of tumor cells in the pathogenesis of malignant neoplasms. This phenomenon, known as the Warburg effect, provides a number of advantages in the survival of neoplastic cells, and its application is considered a potential strategy in the search for antitumor agents. With the aim of developing a promising platform for designing antitumor therapeutics, we synthesized a library of conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones. To gain insight into the determinants of the biological activity of the prepared compounds, we showed that the conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones, which are cytotoxic agents, demonstrate selective activity toward a number of tumor cell lines with glycolysis-inhibiting ability. Moreover, the results of molecular and in silico screening allowed us to identify these compounds as potential inhibitors of the pyruvate kinase M2 oncoprotein, which is the rate-determining enzyme of glycolysis. Thus, the results of our work indicate that the synthesized conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones can be considered a promising platform for designing selective cytotoxic agents against the glycolysis process, which opens new possibilities for researchers involved in the search for antitumor therapeutics among compounds containing piperidone platforms.

Blocking SLC7A11 attenuates the proliferation of esophageal squamous cell carcinoma cells

The role of ferroptosis-associated gene SLC7A11 in esophageal cancer progression is largely unknown, therefore, the effects of blocking SLC7A11 on esophageal squamous cell carcinoma (ESCC) cells are evaluated. Results showed that SLC7A11 was overexpressed in ESCC tissues both in mRNA and protein levels. Blocking SLC7A11 using Erastin suppressed the proliferation and colony formation of ESCC cells, decreased cellular ATP levels, and improved ROS production. Sixty-three SLC7A11-binding proteins were identified using the IP-MS method, and these proteins were enriched in four signaling pathways, including spliceosome, ribosome, huntington disease, and diabetic cardiomyopathy. The deubiquitinase inhibitors PR-619, GRL0617, and P 22077 could reduce at least 40% protein expression level of SLC7A11 in ESCC cells, and PR-619 and GRL0617 exhibited suppressive effects on the cell viability and colony formation ability of KYSE30 cells, respectively. Erastin downregulated GPX4 and DHODH and also reduced the levels of β-catenin, p-STAT3, and IL-6 in ESCC cells. In conclusion, SLC7A11 was overexpressed in ESCC, and blocking SLC7A11 using Erastin mitigated malignant phenotypes of ESCC cells and downregulated key ferroptosis-associated molecules GPX4 and DHODH. The therapeutic potential of targeting SLC7A11 should be further evaluated in the future.

Dehydrocostus lactone suppresses gastric cancer progression by targeting ACLY to inhibit fatty acid synthesis and autophagic flux

INTRODUCTION

Dehydrocostus lactone (Dehy), a natural sesquiterpene lactone from Saussurea lappa Clarke, displays remarkable efficacy in treating cancer and gastrointestinal disorders. However, its anti-gastric cancer (GC) effect remains poorly understood.

OBJECTIVES

Our study aimed to elucidate the anti-GC effect of Dehy and its putative mechanism.

METHODS

The anti-GC effect was assessed with MTT, colony formation, wound healing and transwell invasion assays. Cell apoptosis rate was detected by Annexin V-FITC/PI binding assay. Network pharmacology analysis and XF substrate oxidation stress test explored the underlying mechanism and altered metabolic phenotype. Lipogenic enzyme expressions and neutral lipid pool were measured to evaluate cellular lipid synthesis and storage. Biolayer interferometry and molecular docking investigated the direct target of Dehy. Autophagosomes were observed by transmission electron microscopy and MDC staining, while the autophagic flux was detected by mRFP-GFP-LC3 transfection. The clinical significance of ACLY was confirmed by tissue microarrays. Patient-derived xenograft (PDX) models were adopted to detect the clinical therapeutic potential of Dehy.

RESULTS

Dehy prominently suppressed GC progression both in vitro and in vivo. Mechanistically, Dehy down-regulated the lipogenic enzyme ACLY, thereby reducing fatty acid synthesis and lipid reservation. Moreover, IKKβ was identified as the direct target of Dehy. Dehy inhibited the phosphorylation of IKKβ, promoting the ubiquitination and degradation of ACLY, thereby resulting in lipid depletion. Subsequently, GC cells initiated autophagy to replenish the missing lipids, whereas Dehy impeded this cytoprotective mechanism by down-regulating LAMP1 and LAMP2 expressions, which disrupted lysosomal membrane functions, ultimately leading to apoptosis. Additionally, Dehy exhibited potential in GC clinical therapy as it enhanced the efficacy of 5-Fluorouracil in PDX models.

CONCLUSIONS

Our work identified Dehy as a desirable agent for blunting abnormal lipid metabolism and highlighted its inhibitory effect on protective autophagy, suggesting the future development of Dehy as a novel therapeutic drug for GC.

Acacetin restrains the malignancy of esophageal squamous carcinoma cells via regulating JAK2/STAT3 pathway

Acacetin is a natural flavonoid compound found in diverse plants, which has strong anti-inflammatory and anti-cancer activities. This work aimed at investigating how acacetin functions on esophageal squamous carcinoma cells. In this work, esophageal squamous carcinoma cell lines were subjected to increasing doses of acacetin, and the proliferative, migrative, invasive and apoptotic phenotypes were evaluated by a series of in vitro experiments. Genes related to acacetin and esophageal cancer were predicted by bioinformatics analysis. The levels of apoptosis-relevant proteins and JAK2/STAT3 pathway-relevant proteins in esophageal squamous carcinoma cells were probed by Western blot. It was revealed that acacetin could block the growth and aggressiveness of TE-1 and TE-10 cells and promote the apoptosis. Acacetin treatment induced bax's expression and repressed bcl-2's expression. Notably, acacetin inhibits JAK2/STAT3 pathway in esophageal squamous carcinoma cells. In summary, acacetin inhibits the malignant progression of esophageal squamous carcinoma via restraining JAK2/STAT3 signaling.