Integrated transcriptomic and proteomic analysis of microplasts derived from macrophage-conditioned medium-treated MCF-7 breast cancer cells.

Microplasts are large extracellular vesicles originating from migratory, invasive, and metastatic cancer cells. Here, to gain insight into the role of microplasts in cancer progression, we performed a proteomic and transcriptomic characterization of microplasts isolated from MCF-7 breast cancer cells treated with macrophage-conditioned medium. These cells were found to be viable, highly migratory, and metabolically active, indicating that microplasts derived from these cells are not apoptotic bodies. Transcriptomic/proteomic analyses identified 10273 mRNAs and 821 proteins in microplasts. Interestingly, 377 microplast mRNAs coded for corresponding microplast proteins. Microplast mRNAs and proteins were mainly associated with binding and catalytic activities. Microplasts showed enrichment of mRNAs involved in transcription regulation and proteins involved in processes such as cell-cell adhesion and translation. Pathway analysis showed enrichment of ribosomes and carbon metabolism. These results suggest a close resemblance between microplasts and parent cells, with mRNA and protein cargo relevant in intercellular signaling.