Circ_0005075 promotes hepatocellular carcinoma progression by suppression of microRNA-335

Area of Science:

• Molecular biology
• Cancer research
• RNA biology

Background:

• Noncoding RNAs, including circular RNAs (circRNAs), are crucial in cancer biology.
• circRNAs regulate gene expression and impact cancer prognosis by sponging microRNAs.
• Research on circRNAs in hepatocellular carcinoma (HCC) is limited.

Purpose of the Study:

• To investigate the role of circ_0005075 in HCC development.
• To elucidate the molecular mechanism of circ_0005075 in HCC progression.

Main Methods:

• Quantitative real-time PCR to measure circRNA and miRNA expression.
• In vitro and in vivo experiments to assess HCC progression.
• Western blotting to detect protein expression.
• RNA immunoprecipitation and dual-luciferase reporter assays to confirm interactions.

Main Results:

• circ_0005075 was significantly upregulated in HCC tissues compared to normal tissues.
• Downregulation of circ_0005075 suppressed HCC cell proliferation and migration in vitro and tumor growth in vivo.
• Inhibition of microRNA-335 (miR-335) partially reversed the suppressive effects of circ_0005075 downregulation.
• circ_0005075 directly bound to miR-335, and miR-335 targeted mitogen-activated protein kinase 1 (MAPK1).
• circ_0005075 promoted HCC progression by acting as a sponge for miR-335, thereby regulating MAPK1 expression.

Conclusions:

• circ_0005075 acts as an oncogenic circRNA in HCC progression.
• The circ_0005075/miR-335/MAPK1 axis represents a potential therapeutic target for HCC.