Ovarian cancer usually starts to develop in the fallopian tube or the ovary and later develops a secondary malignant growth in the omentum, which is a layer of fatty tissue surrounds the abdominal organs. Here, the ovarian cancer cells interact with different cells types in the omentum compared with those in the original sites. One of the most predominant cell types in the omentum is the fat cell. Recent studies show that fat cells can support ovarian cancer cell growth and make cancer cells more aggressive and may even become resistant to chemotherapeutic drugs such as cisplatin and taxol. However, how the fat cells support ovarian cancer cells growth is poorly understood.
There are multiple ways that the fat cells can communicate with the ovarian cancer cells. Fat cells can secrete proteins which can be absorbed by the ovarian cancer cells and thus stimulate their growth. Recent studies show that there are other new ways that fat cells can communicate with the cancer cells. One of them is through the secretion of tiny spherical bubbles called exosomes. These exosomes can carry proteins and genetic materials from the one cell type to the other by fusing to the surface of the recipient cells, and subsequently release their cargos into the recipient cells to affect their behavior. Genetic materials can include DNA, mRNA and microRNAs, which is a form of RNAs that has recently been identified. MicroRNAs can regulate gene expression and there are a few thousand of them. Using a new DNA sequencing technique, we have recently identified several microRNAs in the exosomes secreted exclusively by the fat cells. In the proposed study, we, if successful, will provide a new perspective about the inter-relationship between the omental fat cells and the metastatic ovarian cancer cells. Targeting miRNAs delivered in exosomes secreted by the fat cells may be a new therapeutic regimen for ovarian cancer treatment.