Understanding the Role and Clinical Applications of Exosomes in Gynecologic Malignancies: A Review of the Current Literature

Clinical perspectives of rare ovarian tumors: clear cell ovarian cancer

Ovarian clear cell carcinoma (OCCC) is a rare and distinct histological type of epithelial ovarian carcinoma in terms of its histopathological, clinical and genetic features. Patients with OCCC are younger and diagnosed at earlier stages than those with the most common histological type-high-grade serous carcinoma. Endometriosis is considered a direct precursor of OCCC. Based on preclinical data, the most frequent gene alternations in OCCC are mutations of AT-rich interaction domain 1A and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha. The prognosis of patients with early-stage OCCC is favorable, whereas patients at an advanced stage or who have the recurrent disease have a dismal prognosis due to OCCC's resistance to standard platinum-based chemotherapy. Despite a lower rate of response due to its resistance to standard platinum-based chemotherapy, the treatment strategy for OCCC resembles that of high-grade serous carcinoma, which includes aggressive cytoreductive surgery and adjuvant platinum-based chemotherapy. Alternative treatment strategies, including biological agents based on molecular characteristics specific to OCCC, are urgently needed. Furthermore, due to its rarity, well-designed collaborative international clinical trials are needed to improve oncologic outcomes and the quality of life in patients with OCCC.

Plant-derived extracellular vesicles (PDEVs) in nanomedicine for human disease and therapeutic modalities

BACKGROUND

The past few years have witnessed a significant increase in research related to plant-derived extracellular vesicles (PDEVs) in biological and medical applications. Using biochemical technologies, multiple independent groups have demonstrated the important roles of PDEVs as potential mediators involved in cell-cell communication and the exchange of bio-information between species. Recently, several contents have been well identified in PDEVs, including nucleic acids, proteins, lipids, and other active substances. These cargoes carried by PDEVs could be transferred into recipient cells and remarkably influence their biological behaviors associated with human diseases, such as cancers and inflammatory diseases. This review summarizes the latest updates regarding PDEVs and focuses on its important role in nanomedicine applications, as well as the potential of PDEVs as drug delivery strategies to develop diagnostic and therapeutic agents for the clinical management of diseases, especially like cancers.

CONCLUSION

Considering its unique advantages, especially high stability, intrinsic bioactivity and easy absorption, further elaboration on molecular mechanisms and biological factors driving the function of PDEVs will provide new horizons for the treatment of human disease.

Extracellular vesicle contents as non-invasive biomarkers in ovarian malignancies

Ovarian cancer most commonly presents at an advanced stage where survival is approximately 30% compared with >80% if diagnosed and treated before disease spreads. Diagnostic capabilities have progressed from surgical staging via laparotomy to image-guided biopsies and immunohistochemistry staining, along with advances in technology and medicine. Despite improvements in diagnostic capabilities, population-level screening for ovarian cancer is not recommended. Extracellular vesicles (EVs) are 40–150 nm structures formed when the cellular lipid bilayer invaginates. These structures function in cell signaling, immune responses, cancer progression, and establishing the tumor microenvironment. EVs are found in nearly every bodily fluid, including serum, plasma, ascites, urine, and effusion fluid, and contain molecular cargo from their cell of origin. This cargo can be analyzed to yield information about a possible malignancy. In this review we describe how the cargo of EVs has been studied as biomarkers in ovarian cancer. We bring together studies analyzing evidence for various cargos as ovarian cancer biomarkers. Then, we describe the role of EVs in modulation of the tumor microenvironment. This review also summarizes the therapeutic and translational potential of EVs for their optimal utilization as non-invasive biomarkers for novel treatments against cancer.

Exosomal MicroRNA as Biomarkers for Diagnosing or Monitoring the Progression of Ovarian Clear Cell Carcinoma: A Pilot Study

Ovarian cancer is the most common cause of gynecological malignancy-related mortality since early-stage disease is difficult to diagnose. Advanced clear cell carcinoma of the ovary (CCCO) has dismal prognosis, and its incidence has been increasing in Japan, emphasizing the need for highly sensitive diagnostic and prognostic CCCO biomarkers. Exosomal microRNAs (miRNAs) secreted by tumor cells are known to play a role in carcinogenesis; however, their involvement in ovarian cancer is unclear. In this study, we performed expression profiling of miRNAs from exosomes released by five cell lines representing different histological types of ovarian cancer. Exosomes isolated from culture media of cancer and normal cells were compared for miRNA composition using human miRNA microarray. We detected 143 exosomal miRNAs, whose expression was ≥1.5-fold higher in ovarian cancer cells than in the control. Among them, 28 miRNAs were upregulated in cells of all histological ovarian cancer types compared to control, and three were upregulated in CCCO cells compared to other types. Functional analyses indicated that miR-21 overexpressed in CCCO cells targeted tumor suppressor genes PTEN, TPM1, PDCD4, and MASP1. The identified miRNAs could represent novel candidate biomarkers to diagnose or monitor progression of ovarian cancer, particularly CCCO.

Exosomes on Endometrial Cancer: A Biomarkers Treasure Trove?

Endometrial cancer (EC) is one of the main causes of cancer-related death among women. In the last decade, the incidence of EC is on the rise, and the relative 5-year survival remains unchanged. This creates a dire need for new diagnostic and therapeutic approaches that can only result from a deeper understanding of the pathogenesis of the disease. In this direction, exosomes are under heavy research, with two main aims: to identify the potential diagnostic and prognostic markers and to develop technologies based on their use as therapeutic vectors targeting EC cells. Exosomes are widely available in all bodily fluids and are sources of ideal biomarkers for liquid biopsies. They are extracellular vesicles containing DNA, RNA, lipids, and proteins, which they transfer between cells, serving multiple functions and being implicated in both the physiological processes and the pathogenesis of diseases. Of all the biomolecules contained in exosomes, microRNAs (miRNAs) seem to have the most clinical utility in the diagnosis and treatment of EC. Exosomal miRNAs mediate the communication between EC cells, cancer-associated fibroblasts (CAFs), and tumor-associated macrophages (TAMs) and have a pivotal role in the tumor cells' proliferation, epithelial to mesenchymal transition (EMT), and the formation of a tumor microenvironment. They participate in many processes that are tied to carcinogenesis and cancer progression, and they are therefore considered as attractive therapeutic targets. Here, we review the functions of exosomes in EC, focusing on potential biomarkers of diagnostic and prognostic significance or potential therapeutic use.