Evaluation of thymoquinone (TQ) as an antiproliferative, proapoptotic, and immunomodulatory agent in a non-small cell lung cancer cell (NSCLC) line

Abstract

e14644 Background: NSCLC is the most common cause of cancer death worldwide. We performed in vitro testing of Thymoquinone (TQ), a derivative of black caraway seed against NSCLC cell line NCI-H460 Methods: Cells were grown in RPMI and were plated at a density of 5,000 cells per well in a 96 well plate and cell growth determined in the presence of 80 and 100μM of TQ dissolved in DMSO with appropriate solvent only as control. Cell proliferation was determined at 24, 48 and 72 hrs intervals using 3-(4,5-dimethyltiazol 2-yl)-2,5-diphenyltetraolium bromide (MTT) assay. Factorial analyses of variance (ANOVA) were used to determine the effect of TQ and control with the time. Student-Newman-Keuls test was used to determine statistical significance with P value <0.05 considered significant. Apoptosis was detected using Annexin V-FITC Aptosis Detection Kit analyzing the effects of TQ at 24 hrs after treatment by flow cytometry. The immunomodulatory effects of TQ were tested using RayBio Human Cytokine Antibody Array C series 200. NCI-H460 cells (50,000 cells per well in duplicate 6 well plates) were grown in serum free RPMI media. 24 hrs after treatment with TQ or DMSO media was collected and analyzed for expression of various cytokines. Results: The MTT assay showed that TQ at 80 and 100 μM significantly inhibited cell growth as compared to control and at 24 hrs for example, 100 μM TQ inhibited cell growth by 78%. Apoptosis occurred rapidly after treatment with TQ with 73.5% of cells being positive for expression of Annexin-V as detected by flow cytometry after 24 hrs of exposure to TQ as compared to 2.6% of controls. The cytokine array revealed that TQ significantly decreased expression of ENA-78(Epithelial neutrophil activating peptide), and GRO (Growth related oncogene).ENA-78 is correlated with vascularity and tumor growth in NSCLC tumor, whereas GRO is associated with neoangiogenesis. Conclusions: TQ is shown to be a powerful anti-proliferative, pro-apoptotic and anti- angiogenic agent in a NSCLC cell line. No significant financial relationships to disclose.