SQSTM1/p62 promotes the progression of gastric cancer through epithelial-mesenchymal transition.

Background: SQSTM1/p62 is an autophagy-related receptor protein that participates in regulating tumorigenesis and multiple signaling pathways. Gastric cancer (GC) is a common tumor in the digestive tract and continues to pose a significant threat to human health. Therefore, this study aims to investigate the impact of p62 on gastric cancer. Methods: Immunohistochemistry and Western blotting were employed to assess the expression level of the p62 protein in gastric cancer tissues and its correlation with prognosis. Subsequently, in vitro cell experiments were conducted to determine the role of p62 in gastric cancer cell proliferation, migration, and metastasis. Result: The expression of p62 in gastric cancer tissues was significantly higher than in normal tissues. The expression of p62 was positively correlated with poor prognosis in gastric cancer patients. In vitro cell experiments indicated that p62 promotes gastric cancer cell proliferation and migration. Mechanistically, elevated p62 expression induced epithelial-mesenchymal transition (EMT), leading to upregulation of E-cadherin and downregulation of N-cadherin and vimentin. Conclusion: This study provides novel and robust evidence for the mechanism by which elevated p62 expression promotes the progression of gastric cancer. It offers promising therapeutic targets for anti-tumor treatment strategies in gastric cancer patients.

Correlation of mir-221-3p differential expression with clinical characteristics of gastric cancer patients.

BACKGROUND: Gastric cancer (GC) is one of the most common digestive malignancies. Although miR-221-3p was defined as a novel biomarker in many types of cancer, the relationship between its expression differences and the clinicopathological characteristics and prognosis of GC patients was yet to be fully understood. METHODS AND RESULTS: TCGA database was utilized to predict the potential biological function of miR-221-3p in GC. QRT-PCR and RNA FISH were performed to detect the expression levels of miR-221-3p in GC. The miR-221-3p expression levels in GC tissues and cells were significantly higher than those in paracancerous tissues (p < 0.001) and normal gastric mucosal cells (p < 0.05). Higher expression levels of miR-221-3p were associated with tumor diameter ≥ 4 cm (χ2 = 5.519, p = 0.019), cTNM stage (III + IV) (χ2 = 28.013, p = 0.000), lymph node metastasis (χ2 = 23.272, p = 0.000) and distant metastasis (χ2 = 7.930, p = 0.005). Kaplan-Meier survival analysis showed a better prognosis for GC patients with miR-221-3p low expression(HR = 4.520, 95% CI: 1.844-11.075). CONCLUSIONS: miR-221-3p is highly expressed in GC tissues, which plays an important role in tumorigenesis, invasion and metastasis. miR-221-3p may become an important biomarker and potential molecular therapeutic target for patients with GC.