Twist1-YY1-p300 complex promotes the malignant progression of HCC through activation of miR-9 by forming phase-separated condensates at super-enhancers and relieved by metformin.

Hepatocellular carcinoma (HCC) is one of the leading causes of death, which deserves further study to reveal the underlying molecular mechanisms. Studies have shown that miR-9 in associated with poor prognosis in HCC patients. However, the mechanisms of transcriptional activation regulation of miR-9 and its role in the malignant progression of HCC have been rarely investigated. Some transcriptional coactivators can form phase-separated condensates at super-enhancers that compartmentalize and concentrate the transcription apparatus to drive robust gene expression. Here, we demonstrate that Twist1 and YY1 could form a transcriptional complex with p300, creating local high-concentration phase-separated interaction hubs at the super-enhancers of miR-9 and activate its expression to promote the malignant progression of HCC by stimulating the migration and invasion of hepatocellular carcinoma cells. Twist1-YY1-p300 phase-separated condensates were disrupted by metformin (Met) and thus reduce miR-9 expression, thereby inhibiting the malignant progression of HCC. Our study demonstrates that the Twist1 transcriptional factor complex involved in the malignant progression of HCC can form phase separation condensates at super-enhancers of miR-9 to promote the expression of oncogenes in HCC cells. It provides a potential target for the therapy of HCC and offers insights into the mechanism of Met in HCC inhibition.