Lemon Peel Polyphenol Extract reduces Interleukin-6 dependent Invasiveness and Matrix Metalloproteinase-9/2 Expression in human gastric and primary colon carcinoma cells.

Introduction: lemon peel polyphenols extract (LPE) from lemon (Citrus limon) agroindustry’s wastes, shows antioxidant and anti-cancer properties in various cancer cells (1). Our aim was to explore the LPE protective effect using an in vitro inflammatory model consisting of Interleukin-6 (IL-6) treated human gastric adenocarcinoma (MKN-28 and AGS) and primary colon cancer (T88 and T93) cells. We evaluated the LPE effect on IL-6-dependent cell invasiveness and matrix metalloproteinases (MMP)-9/2 expression. Materials and Methods: cells pretreated with LPE (1) at non-cytotoxic concentrations (0.5 or 1 µg/ml gallic acid equivalent, 6 h), and then exposed to IL-6 (50 ng/ml, 24 h) were analyzed for: cell migration (wound assay) and invasiveness (Boyden chamber assay); MMP-9/2 mRNA expression level (q-PCR); gelatinolytic activity (gelatin zymography) and protein expression level (SDS-PAGE and Western blotting). Results: LPE pretreatment reduces the invasiveness of these cancer cells through the inhibition of IL-6-induced MMP-9/2 up-regulation (2,3). Conclusions: LPE represents a cancer protective agent and a green strategy for residual biomass recovery that refocus economic and environmental aspects of agro-food industry. References: 1. Di Donato et al. 2018, Waste Biomass Valorization, 9, 1567. 2. Pagliara et al. 2019, Biomolecules, 9, 833. 3. Pagliara et al. 2021, Molecules, 26, 7076.