The role of three different lycopene extracts on human lung adenocarcinoma cell line

Lycopene is an antioxidant carotenoid pigment found in a wide variety of vegetables and fruits, together with other lipophilic phytochemicals. Antioxidants have different effects on cancer progression. Non-small cell lung cancer (NSCLC) accounts for >80% of all lung cancers. Inflammation is a key event in cancer development. This study aims to evaluate in vitro the effects of administration of three different oleoresins containing lycopene on human NSCLC cell line, A549. The oleoresins, obtained by the supercritical CO2 green extraction technology from watermelon (Lyc W), GAC (Lyc G) and tomato (Lyc T), were chlatrated in ?-cyclodextrins (?-CD) in order to improve their stability and promote the dispersion of the lipophilic compounds in the cell-culture aqueous medium. They were tested at different concentrations (from 0.5 to 10 µM lycopene) on A549 by the Cell Proliferation Assay (MTS) for 24 hrs, Annexin V-FITC/PI apoptosis test and ELISA for Interleukin-8 (IL-8) release, for 48 and 72 hrs. The oleoresins were characterized by a different composition in carotenoids and tocochromanols, with Lyc W showing the highest lycopene/tocochromanol ratio. At 10 µM, the three extracts showed conflycting behaviors: Lyc W increased cell apoptosis (p=0.01) and decreased cell proliferation (p=0.009) and IL-8 release (p=0.03), whereas Lyc G and Lyc T decreased cell apoptosis(p=0.01 and p=0.04, respectively) and increased cell proliferation (p=0.01 and p=0.04, respectively) and IL-8 release (both p=0.01). Furthermore, at 3 µM, Lyc G and Lyc T decreased cell apoptosis (p=0.009 and p=0.01, respectively). In Lyc W the highest amount of lycopene is able to counteract and revert the survival effect of tocochromanols, supporting the importance to evaluate the real effect of antioxidant supplementation on lung cancer which not only may have no anticancer benefits but even increase cancer aggressivity.