Phenolic phytochemicals derived from red pine (Pinus densiflora) inhibit the invasion and migration of SK-Hep-1 human hepatocellular carcinoma cells.

Considerable attention has recently been focused on identifying chemopreventive phytochemicals derived from medicinal plants. Here, we analyzed phenolic phytochemicals from red pine (RP) leaves and found epigallocatechin gallate (EGCG) and epigallocatechin (EGC), and catechin gallate (CG) as their major phenolic phytochemicals. This article also investigated whether RP leaf extract and its phenolic phytochemicals inhibit the invasion of SK-Hep-1 human hepatocellular carcinoma cells (SK-Hep-1 cells). RP suppressed the invasion and the migration of SK-Hep-1 cells. EGCG and CG also inhibited the invasion and migration, with EGC exhibiting a lower efficacy. Matrix metalloproteinases (MMPs), particularly gelatinase-A (MMP-2) and gelatinase-B (MMP-9), degrade components of the basement membrane and are strongly implicated in invasion and metastasis formation of malignant tumors. RP suppressed both MMP-2 and MMP-9 activities. EGCG and CG reduced the activities of MMP-9 and MMP-2 in a dose-dependent manner, with EGC exhibiting a lower efficacy on both MMPs. Our results suggest that RP inhibits tumor invasion and migration, which may be attributed to the effects of EGCG and CG. In particular, EGCG plays a key role in the efficacy of RP against hepatocarcinogenesis.