Advances of exosome in the development of ovarian cancer and its diagnostic and therapeutic prospect.

Ovarian cancer is the leading cause of female gynecological cancer mortality. Most patients with ovarian cancer are diagnosed with advanced stage because of lack of early symptoms, physical signs, and sensitive tumor biomarkers. The standard treatment includes cytoreductive surgery and platinum-based chemotherapy (usually platinum combined with paclitaxel). Despite that postoperative adjuvant chemotherapy prolongs survival time, most patients go through relapse within 6-12 months after the treatment. Thus, elucidating the molecular mechanism in cancer development is essential to promote early diagnosis and novel treatments. The role of exosome has been highlighted in multiple research fields in recent years. Exosome has been described as nano-sized vesicle secreted by multiple mammalian cell types, carrying cargos like proteins, miRNAs, mRNAs, and lipids. It participates in the formation of tumor microenvironment and the development of tumorigenesis and drug resistance in ovarian cancer. Meanwhile, it may also play a pivotal role in diagnosis, efficacy evaluation, and prognosis. Besides, studies show that exosome and its processed products have promising value in ovarian cancer treatment. The aim of the current review is to describe the characteristics of exosome in ovarian cancer, especially focusing on its role in immune modulation and drug resistance, hoping to provide new information on its implications in cancer diagnosis and treatment.