Clear cell ovarian cancer (CCOC) is the 2^nd most common type of ovarian cancer, arising from cells from the lining of the uterus that have implanted in the ovary (endometriosis). Clinically, CCOC is more aggressive, widely metastatic, and more resistant to standard chemotherapy compared to other types of epithelial ovarian cancer. Understanding the biology of CCOC, and how they spread, may provide novel therapeutic targets not only for these ovarian tumors, but also similar tumours that grow in the uterus. It has been shown that when tumor cells come under stress due to a lack of oxygen or nutrients in their surrounding environment, they must rapidly activate stress response pathways to stay alive. It is now clear that by doing so, tumor cells can also become more aggressive and metastasize (spread). Our group has previously shown that a specific metabolic enzyme, called cystathionine gamma-lyase (CTH), is expressed by CCOC but not other types of ovarian cancer. Interestingly, this enzyme plays substantial roles in the adaptive response to stress, which is a key aspect of cancer spread. We will explore the role of this enzyme in the progression of CCOC, and its potential therapeutic use in inhibiting metastasis which could greatly improve outcomes for these patients.