Abstract LB167: Functional extracellular vesicle profiling with nanochips for cancer diagnosis and monitoring
Authors: Zeng Yong , Chen Shibo , Wen Yunjie , Xu Liang 
Published: June 2022

Abstract
Currently, most cancer cases are diagnosed with local or distant metastases that lead to ~90% of deaths from cancer. Widely used radiographic imaging detects large-size tumors and often fails to detect changes in tumor burden. Genomics centered on gene alterations faces challenges in capturing instant status of malignancy, such as invasive/metastatic phenotypes. In addition, tissue biopsy is highly invasive, costly, and often infeasible to repeat. Thus, novel non-invasive markers and tests that complement current paradigms for early detection and accurate tracking of tumor dynamics are urgently needed to improve clinical decision making and treatment. Extracellular vesicles (EVs), including exosomes, are emerging as a new class of liquid biopsy for cancer diagnosis and monitoring response to treatment. Growing evidence indicates important functions of EVs in tumor development, invasion, and metastasis, including matrix remodeling via transporting matrix metalloproteases (MMPs). However, their clinical relevance remains largely undetermined, partially owing to the challenges in EV analysis. We recently report a nanoengineered lab-on-a-chip system capable of integrative functional phenotyping of tumor-associated EVs. A generalized, high-resolution colloidal inkjet printing method was developed to afford robust and widely adaptable manufacturing of 3D nanopatterned microdevices. Enabled by this new nanofabrication technique, we built an integrated chip for multiparametric analysis of exosome circulation level, subtype, and enzymolytic activity (ExoCLUE). With various cancer cell lines and isogenic cell models created by CRISPR/Cas9 editing, we demonstrated that this nanochip affords ultrasensitive and specific analysis detection of the expression and proteolytic activity of MMP14 on EVs to measure in vitro cell invasiveness. With the experimental and spontaneous mouse models of breast cancer metastasis, we showed that the ExoCLUE chip with low sample input enables longitudinal monitoring of in vivo tumor growth and metastasis in single mice. Lastly, the ExoCLUE was assessed for clinical analysis of plasma from two independent training (n = 30) and validation (n = 70) cohorts of breast cancer patients. The proteolytic activity of MMP14+ EVs showed good performance to detect the patients (AUC = 0.986 for the validation set). Combined with a machine learning algorithm, the chip-based integrative functional EV analysis enabled classification of the control, pre-malignant ductal carcinoma in situ, invasive ductal carcinoma, and locally metastatic IDC patients with a high accuracy of 92.9%. Lastly, we have scaled up the ExoCLUE system to a high-throughput nanoarray platform for highly multiplexed functional EV profiling. Overall, our nanochip technology could provide a useful liquid biopsy tool to improve animal studies and clinical diagnosis of cancer.
Citation Format: Yong Zeng, Shibo Chen, Yunjie Wen, Liang Xu. Functional extracellular vesicle profiling with nanochips for cancer diagnosis and monitoring [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB167.