Protosappanin B Exerts Anti-tumor Effects on Colon Cancer Cells via Inhibiting GOLPH3 Expression
Protosappanin B (PSB) is a major active compound found in Lignum Sappan extract. While the antiproliferative effects of Lignum Sappan extract have been demonstrated in various cancer cell types, the specific impact of PSB on tumor progression remains poorly understood. This study aimed to investigate the anti-tumor effects of PSB on human colon cancer cells by modulating intracellular signaling pathways and the expression of Golgi phosphoprotein 3 (GOLPH3) both in vitro and in vivo. Our results showed that PSB effectively inhibited the viability and migration of SW620 cells and induced apoptosis, although it had minimal effects on HCT116 cells. Additionally, PSB significantly reduced the expression of p-AKT, p-p70S6K, β-catenin, and p-ERK1/2 proteins in SW620 cells, with these effects being reversed by specific signaling pathway agonists. Notably, PSB also suppressed GOLPH3 expression in SW620 cells in a concentration-dependent manner. However, SW620 cells transfected with lentiviral vectors overexpressing GOLPH3 were able to effectively resist the cytotoxic effects of PSB in vitro. In a xenograft model using SW620 cells overexpressing GOLPH3, PSB significantly inhibited tumor growth by suppressing GOLPH3 expression. Collectively, these findings reveal a novel anti-cancer mechanism of PSB, involving the inhibition of GOLPH3 expression and modulation of intracellular signaling pathways in colon cancer cells. PSB may therefore represent a promising new therapeutic agent for colon cancer.