MicroRNAs in small extracellular vesicle (sEV-
miRNAs) have been widely investigated as crucial regulated molecules secreted by
tumor cells to communicate with surroundings. It is of great significance to explore the loading mechanism of sEV-
miRNAs by
tumor cells. Here, we comprehensively illustrated a reasoned loading pathway of batched
tumor-promoting sEV-
miRNAs in
non-small cell lung cancer (NSCLC) cell line A549 with the application of a multi-omics method. The
protein heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) was strictly selected as a powerful sEV-
miRNA loading
protein from
miRNA-binding
proteome and further verified through small
RNA sequencing after hnRNPA1 silence. In terms of the mechanism, SUMOylated hnRNPA1 in sEVs was verified to control sEV-
miRNA loading. Subsequently, as a scaffolding component of caveolae,
caveolin-1 (CAV1) was detailedly demonstrated to assist the loading of SUMOylated hnRNPA1 and its binding
miRNAs into sEVs. Inhibition of CAV1 significantly prevented SUMOylated hnRNPA1 from encapsulating into sEVs, resulting in less enrichment of sEV-
miRNAs it loaded. Finally, we confirmed that hnRNPA1-loaded sEV-
miRNAs could facilitate
tumor proliferation and migration based on database analysis and cytological experiments. Our findings reveal a loading mechanism of batched
tumor-promoting sEV-
miRNAs, which may contribute to the selection of therapeutic targets for
lung cancer.