Abstract 1822: Artemisia annua Lpolyphenols augment b-lapachone effects on oxaliplatin-resistant HCT 116 colorectal cancer cells by downregulating TERT, CD44, EGFR and oxaliplatin resistance-related proteins of OXP-R-Hct 116 cells

Abstract We previously demonstrated that β-lapachone (β-Lap) exerts stronger anticancer activity on oxaliplatin-resistant HCT116 colorectal cancer cells (Oxp-R-HCT 116 cells) than parental HCT116 cells (p-HCT 116 cells) by downregulating the oxaliplatin resistance-related upregulated proteins (Oxp-RR-Proteins) proteins in Oxp-R-HCT 116 cells, such as SOD1, MAPK, and nucelophosmin. We also demonstrated polyphenols extracted from Korean Artemisia annua L. (pKAL) exerts anticancer activity on radio-resistant MDA-MB-231 human breast cancer cells by suppressing stem cell phenotype, β-catenin, and MMP-9. In this study, we found that pKAL significantly enhanced the anticancer activity of β-lapachone (β-Lap) on oxaliplatin-resistant (Oxp-R) HCT116 colorectal cancer cells. The aim of this study is to elucidate how pKAL enhance the anticancer effects of β-Lap on Oxp-R-HCT 116 cells. CCK-8 assay, phase-contrast microscopy analysis, and morphological analysis with hematoxylin stain revealed that the anticancer effect of β-Lap is more enhanced by pKAL on Oxp-R-HCT 116 cells over 60 hr. This phenomenon was associated with suppression of oxaliplatin resistance-related upregulated proteins (Oxp-RR-Proteins) (p53, ERK, and β-catenin), and downregulation of cell survival- and stemness-related proteins (TERT, CD44 and EGFR) that were not up-regulated in Oxp-R-HCT 116 cells. Protein-protein interaction network analysis of the 21 proteins that showed large difference in expression between before and after the combined treatment of pKAL and β-Lap in HCT116-OxPt-R cells revealed that the enhanced anticancer effect of β-Lap by pKAL was related to the inhibition of negative regulation of apoptotic process and the induction of DNA damage through TERT, CD44, and EGFR-mediated multiple signaling networks. The detailed western blot analysis for anti-cancer effects of pKAL revealed that pKAL alone also suppressed the expression of TERT, CD44 and EGFR in p-HCT 116 cells as well as Oxp-R-HCT 116 cells while β-Lap alone did not influence the expression of them. In addition, for some of the Oxp-RR-Proteins of Oxp-R-HCT 116 cells (p53, ERK, and β-catenin) were suppressed by pKAL alone, but not others. However, some other Oxp-RR-Proteins of Oxp-R-HCT 116 cells that were not suppressed by pKAL alone were significantly suppressed by the combination treatment of pKAL and β-Lap. These findings suggest that pKAL enhanced the anti-cancer effects β-Lap by suppressing TERT, CD44, and EGFR-mediated multiple signaling networks as well as some of the Oxp-RR-Proteins of Oxp-R-HCT 116 cells. In conclusion, this study suggests that pKAL enhance the anticancer effects of β-Lap on OXP-R-Hct 116 cells by downregulating CD44, EGFR and some of the Oxp-RR-Proteins of Oxp-R-HCT 116 cells. Citation Format: Won Sup Lee, Eun Joo Jung, Hye Jung Kim, Sung Chul Shin, Gon Sup Kim, Jin-Myung Jung, Soon Chan Hong, Choong Won Kim. Artemisia annua Lpolyphenols augment b-lapachone effects on oxaliplatin-resistant HCT 116 colorectal cancer cells by downregulating TERT, CD44, EGFR and oxaliplatin resistance-related proteins of OXP-R-Hct 116 cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1822.