LAUSR

Tumors are hierarchically organized by a rare population of cancer stem cells (CSCs) that contributes to cancer initiation, progression, and treatment failure. A better understanding of the molecular mechanisms underlying urothelial CSC regulation and the identification of key molecules associated with CSC generation and maintenance are pivotal for the molecular-targeting therapy. CD24 is overexpressed and acts as a lynchpin of tumorigenesis and metastatic progression in urothelial carcinoma of the bladder (UCB). However, its contribution to cancer stem-like traits of CD24 have not been determined. The functional relevance of CD24 was evaluated using in vitro and in vivo approaches. The knockdown of CD24 attenuated cancer stemness properties including sphere formation, self-renewal, invasion, chemo-resistance, and tumor initiation. The high-CD24-expressing cells, isolated from patient-derived UCB xenograft tumors, exhibited their enhanced stemness properties. Biologically, CD24 was associated with the expression of several key CSC-related molecules, including CD133, ABCG2, and YAP1. In human UCB samples, CD24 was overexpressed not only in primary tumors, but also in urine from UCB subjects. Conclusion: CD24 plays a crucial role in maintaining the urothelial cancer stem-like traits. Note: This abstract was not presented at the meeting. Citation Format: Akira Oki, Mohammad Obaidul Hoque. CD24 regulates cancer stem cell like traits in bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1162.