Despite various therapeutic developments, ovarian cancer is still one of the most lethal diseases in women. In 2018, almost 22,000 women in the US were diagnosed with ovarian cancer. Over 14,000 women died from it due to a relative lack of targeted agents leading to systemic toxicity, multidrug resistance (MDR) and ultimately to insufficient therapeutic efficacy and metastasis. Thus, ovarian cancer treatment with optimized targeting toward the tumor could produce a clinical advantage. Multiple lines of evidence and several clinical trials solidified the idea that extracellular vesicles, called “exosomes,” can be a potential cancer-targeting solution due to their small size (40~150 nm), biocompatibility, and therapeutic encapsulation and delivery. It is important to note that the surface modification of exosomes could enhance their therapeutic role as a drug delivery system, specifically targeting ovarian cancer and improving therapeutic outcomes. Currently, there are two major methods of exosome surface modification to endow their active targeting efficacy: 1) genetically engineered mother cells to embed targeting proteins and 2) chemical conjugation of a targeting ligand on the exosome. However, both methods require extensive amounts of time and labor to optimize for a feasible clinical application. Thus, alternative methods of exosome surface modification must be developed. In this proposal, we aim to develop an innovative exosome surface-modification method composed of anchor-spacer-ligand (ASL). Lipophilic near-infrared dyes as Anchors will be incorporated into the exosome membrane and produce their nanoconfinement mediated multifold thermal energy. It could inhibit tumor growth and trigger drug release, as evidenced by our preliminary data. Spacers will prevent exosome aggregation and systemic excretion. As targeting Ligands, we will use antibody candidates derived from the injection of ovarian cancer exosome into the animal because they could specifically bind to the exosomes and their mother ovarian cancer cells. Our preliminary data showed that preferential delivery of a drug (doxorubicin) to αvβ3 integrin overexpressing ovarian cancer cells and consequent cell killing efficacy by ASL exosomes coated by RGD peptide that specifically interaction at αvβ3 integrin. Another preliminary study demonstrated that a newly synthesized co-modulator that simultaneously depletes glutathione (MDR contributor) and vascular endothelial growth factor (VEGF: metastasis contributor) inhibits both MDR and metastasis of ovarian cancer. Therefore, the strategy of combining all of the above advantages into an exosome will make an innovative therapeutic platform to treat ovarian cancer, and to our knowledge, it is the first integrated strategy of this type. To achieve this goal, we will prepare a series of anchor-spacerligand conjugates and co-modulators and then integrate them to formulate and optimize co-modulator encapsulating ASL exosome...