Exosomes contribute to several aspects of tumor progression:
1. Metastasis: Exosomes can prepare pre-metastatic niches by altering the microenvironment in distant organs, making them more conducive for tumor cell colonization. 2. Angiogenesis: They promote the formation of new blood vessels by transferring angiogenic factors, thereby supplying the growing tumor with necessary nutrients and oxygen. 3. Immune Modulation: Tumor-derived exosomes can modulate the immune system to favor tumor survival by suppressing anti-tumor immune responses and promoting regulatory T cells. 4. Drug Resistance: Exosomes can transfer drug resistance genes and proteins between cancer cells, contributing to the development of resistance to chemotherapy.
