Alix‐normalized exosomal programmed death‐ligand 1 analysis in urine enables precision monitoring of urothelial cancer

• DOI: 10.1111/cas.16106
• Publication Date: 2024-03-14T03:11:05Z
• Authors: Hyun‐Kyung Woo; Juhee Park; Kyung Hwan Kim; Ja Yoon Ku; Hong Koo Ha; Yoon‐Kyoung Cho
• Keywords: Exosome; Urothelial cancer; Tetraspanin

Anti-programmed death-ligand 1 (PD-L1) Ab-based therapies have demonstrated potential for treating metastatic urothelial cancer with high PD-L1 expression. Urinary exosomes are promising biomarkers liquid biopsy, but urine's variability requires normalization accurate analysis. This study proposes using the PD-L1/Alix ratio to normalize exosomal signal intensity Alix, an internal protein less susceptible heterogeneity concerns than surface markers. Extracellular vesicles were isolated ExoDisc and characterized various methods, including ExoView analyze tetraspanins, PD-L1, Alix on individual exosomes. On-disc ELISA was used evaluate Alix-normalized in 15 patients during initial treatment cycle Tecentriq. Results showed that range relatively uniform, whereas tetraspanin marker varied exosome particles. more reliable detecting expression standard plate ELISA-based measurement. Using is a approach conventional methods monitoring patient status. Overall, provides practical method urine samples from cancer.