Verification of the role of exosomal microRNA in colorectal tumorigenesis using human colorectal cancer cell lines

• DOI: 10.1371/journal.pone.0242057
• Publication Date: 2020-11-11T18:37:13Z
• Authors: Gyoung Tae Noh; Jiyun Kwon; Jungwoo Kim; Minhwa Park; Da-Won Choi; Kyung-Ah Cho; So-Youn Woo; Bo-Young Oh; Kang Young Lee; Ryung-Ah Lee
• Keywords: 0301 basic medicine; THP-1 Cells; Science; 610; MicroRNAs / genetics*; Exosomes; Cell Line; Jurkat Cells; 03 medical and health sciences; Cell Line, Tumor; Tumor Microenvironment; Humans; Exosomes / genetics*; Neoplastic; Tumor; Sequence Analysis, RNA; Q; R; 600; 3. Good health; Gene Expression Regulation, Neoplastic; MicroRNAs; Gene Expression Regulation; RNA; Medicine; Colorectal Neoplasms; Sequence Analysis; HT29 Cells; Colorectal Neoplasms / genetics*; Research Article

Exosomes are a group of small membranous vesicles that are shed into the extracellular environment by tumoral or non-tumoral cells and contribute to cellular communication by delivering micro RNAs (miRNAs). In this study, we aimed to evaluate the role of exosomal miRNAs from colorectal cancer cell lines in tumorigenesis, by affecting cancer-associated fibroblasts (CAFs), which are vital constituents of the tumor microenvironment. To analyze the effect of exosomal miRNA on the tumor microenvironment, migration of the monocytic cell line THP-1 was evaluated via Transwell migration assay using CAFs isolated from colon cancer patients. The migration assay was performed with CAFs ± CCL7-blocking antibody and CAFs that were treated with exosomes isolated from colon cancer cell lines. To identify the associated exosomal miRNAs, miRNA sequencing and quantitative reverse transcription polymerase chain reaction were performed. The migration assay revealed that THP-1 migration was decreased in CCL7-blocking antibody-expressing and exosome-treated CAFs. Colon cancer cell lines contained miRNA let-7d in secreted exosomes targeting the chemokine CCL7. Exosomes from colorectal cancer cell lines affected CCL7 secretion from CAFs, possibly via the miRNA let-7d, and interfered with the migration of CCR2+ monocytic THP-1 cellsin vitro.