[Anwulignan inhibits malignant phenotypes of gastric cancer cells by antagonizing activation of the JAK1/STAT3 signaling pathway].

METHODS

To evaluate the inhibitory effect of anwulignan (ANW) on malignant biological behaviors of gastric cancer cells and explore its underlying molecular mechanism.

METHODS

The inhibitory effect of ANW on viability and proliferation of gastric cancer HGC-27 and SGC-7901 cells were evaluated using CCK-8 assay, EdU staining and colony formation assay. In a nude mouse model bearing gastric cancer xenografts, the effect of ANW on tumor cell proliferation was examined using immunohistochemistry for Ki-67. The changes in cell cycle, apoptosis, migration, invasion, and expressions of MMPs and epithelial-mesenchymal transition (EMT) markers following ANW treatment were detected using flow cytometry, TUNEL staining, Western blotting, Transwell assay, and qPCR. The role of the JAK1/STAT3 signaling pathway in mediating the anti-tumor activity of ANW was validated by detecting JAK1/STAT3 phosphorylation, pathway activation and siRNA-mediated JAK1 knockdown experiments.

RESULTS

In HGC-27 and SGC-7901 cells, ANW dose-dependently suppressed cell proliferation and colony formation, induced G1 cell cycle arrest, and downregulated the expressions of cyclin D1/CDK2 and P53. ANW treatment significantly inhibited tumor growth and decreased Ki-67 positivity in the mouse xenografts. ANW effectively promoted cell apoptosis, suppressed Bcl-2 expression, upregulated cleaved caspase-3 and Bax expressions, inhibited migration and invasion, lowered MMP-2/MMP-9 expressions, and blocked EMT progression in gastric cancer cells. Mechanistically, ANW significantly inhibited JAK1/STAT3 phosphorylation, while the JAK1/STAT3 activator RO8191 reversed the anti-tumor effect of ANW; JAK1 knockdown mimicked and enhanced the inhibitory effect of ANW on gastric cancer cells. ANW significantly inhibited EMT in the mouse xenografts, and this effect was attenuated by RO8191 treatment.

CONCLUSIONS

ANW inhibits malignant phenotype of gastric cancer cells by inhibiting the activation of the JAK1/STAT3 signaling pathway, thereby inducing cell cycle arrest, promoting apoptosis, and suppressing EMT and MMP-mediated invasion and migration, suggesting the potential of ANW as a therapeutic agent for gastric cancer.