**5.1 EVs as a drug delivery system**

EVs can be employed as a drug delivery system that targets cancer cells directly. Harboring packages of chemotherapeutic agents, the EVs can be manufactured to express cell surface antigens and receptors that target it toward cancer cells and spare normal cells, maximizing cytotoxic effect while sparing healthy tissue. In recent work Tang developed a model in which they incubated tumor cells with chemotherapy; and the tumor cells subsequently packaged the chemotherapy into EVs [26]. Tang's group then took these EVs and demonstrated tumor-killing effect in mice with minimal side effects [26]. Therefore, if researchers translate this murine model into a therapy for EOC patients, EVs can be customized to carry the antitumor agents that are effective for a particular tumor. While chemotherapy affects tumor cells, it is also a treatment that damages healthy tissue, causing patients to experience a wide range of side effects. By having a treatment that can precisely target cancer cells while sparing normal tissues, clinicians could safely administer treatments to patients that could control or even cure EOC while avoiding harm.
