Protein Targeted in Ovarian Cancer Stem Cells
Posted: Tuesday, December 24, 2019
Investigative work continues on protein Thy-1 (CD90) in ovarian cancer stem cells and its potential as a therapeutic target. Research by Ofer Reizes, PhD, of the Cleveland Clinic, and colleagues shows that Thy-1 is more highly expressed in ovarian cancer stem cells than in noncancer stem cells, and in ovarian cancer compared with benign ovarian epithelium, and that its presence is highest in serous and endometrial subtypes of ovarian cancer. Aggressively malignant, cancer stem cells “retain the ability to self-renew, exhibit increased proliferation and chemoresistance, and may be a means of harboring disease that evades standard treatment strategies,” according to the research team.
These research findings, published in the Journal of Ovarian Research, show that patients with serous ovarian cancers with high expression of Thy-1 in cancer stem cells have poorer outcomes (median progression-free survival = 15.8 vs. 18.3 months; median overall survival = 40.1 vs. 45.8 months). Furthermore, they commented that a “particularly compelling” finding was that women with endometrioid ovarian cancer with high expression of Thy-1 in cancer stem cells were three times more likely to experience recurrent disease than women with low expression of Thy-1. However, although cells with high expression of Thy-1 demonstrate increased proliferation and self-renewal and predict poor prognosis, “Thy-1 knockdown in ovarian cancer cells decreases proliferative capacity and self-renewal capacity, [and so] represents a potential therapeutic target.”
The overriding goal is to target the cells that evade conventional systemic chemotherapy and retain the ability to metastasize, noted Dr. Reizes and colleagues. The ovarian cancer paradox, they continued, “is that although we have generally efficacious chemotherapy agents in the primary setting, we fail to target microscopic cells that escape primary therapy and progress into recurrent, almost universally fatal, disease. We [must] further…understand the role of cancer stem cells as predictors and mediators of recurrence so that we can target these cells with the goal of keeping patients disease-free.”
Disclosure: The study authors reported no conflicts of interest.