Abstract 5433: Functional involvement of ribosomal protein L9 to colorectal cancer stemness

Abstract We have previously demonstrated that targeting of ribosomal protein L9 (RPL9) suppresses the growth of colorectal cancer (CRC) via the inactivation of Id-1/NF-κB signaling axis which is known to augment tumor stemness. Thus we aimed in this study to investigate whether the function of RPL9 was associated with CRC stemness properties. It was initially evidenced that inhibition of RPL9 expression reduces the migration and invasion abilities of HT29 parental cell population. We have then sorted out CD133+ cancer stem cells (CSCs) from HT-29 parental cell culture and treated RPL9-specific siRNAs to the isolated CSCs to observe the effect of RPL9 targeting on stemness. As results, knockdown of RPL9 significantly suppressed the proliferation potential and sphere forming capacity of CD133+ HT29 CSCs accompanying with the reduction in CD133 and Id-1 levels. Reflecting these molecular alterations, targeting RPL9 also inhibited the abilities of migration and invasion in CD133+ HT29 CSCs population. Taken together, these findings suggest that RPL9 could be a therapeutic target for both primary CRC treatment and the prevention of metastasis and/or recurrence. Citation Format: Eun-Hye Jeon, Keun Uk Park, Hun-Mo Ryoo, Ilseon Hwang, Yun-Han Lee. Functional involvement of ribosomal protein L9 to colorectal cancer stemness [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 5433.