Sulforaphane Suppresses the Nicotine-Induced Expression of the Matrix Metalloproteinase-9 via Inhibiting ROS-Mediated AP-1 and NF-κB Signaling in Human Gastric Cancer Cells

Sulforaphane, a natural phytochemical compound found in various cruciferous vegetables, has been discovered to present anti-cancer properties. Matrix metalloproteinase-9 (MMP-9) plays a crucial role in gastric Cancer metastasis. However, the role of sulforaphane in MMP-9 expression in gastric Cancer is not yet defined. Nicotine, a psychoactive alkaloid found in tobacco, is associated with the development of gastric Cancer. Here, we found that sulforaphane suppresses the nicotine-mediated induction of MMP-9 in human gastric Cancer cells. We discovered that Reactive Oxygen Species (ROS) and MAPKs (p38 MAPK, ERK1/2) are involved in nicotine-induced MMP-9 expression. AP-1 and NF-κB are the critical transcription factors in MMP-9 expression. ROS/MAPK (p38 MAPK, ERK1/2) and ROS functioned as upstream signaling of AP-1 and NF-κB, respectively. Sulforaphane suppresses the nicotine-induced MMP-9 by inhibiting ROS-mediated MAPK (p38 MAPK, ERK1/2)/AP-1 and ROS-mediated NF-κB signaling axes, which in turn inhibit cell invasion in human gastric Cancer AGS cells. Therefore, the current study provides valuable evidence for developing sulforaphane as a new anti-invasion strategy for human gastric Cancer therapy.