According to a recent article published in the International Journal of Gynecologic Oncology, cancer expression of cyclooxygenase-2 (COX-2) and P-glycoprotein may help predict which patients with advanced ovarian will not respond well to chemotherapy.
Ovarian cancer is a malignancy that arises from various different cells within the ovaries. Approximately 25,000 new cases of ovarian cancer are diagnosed in the United States each year. Standard treatment for ovarian cancer is dependent upon the extent of spread of the cancer, but typically consists of the surgical removal of as much of the cancer as possible, as well as chemotherapy and/or radiation therapy. Unfortunately, detection of ovarian cancer most often occurs after the cancer has spread from the ovary to several and/or distant sites in the body. This leads to dismal overall long-term survival rates, particularly in women with advanced disease. Researchers are attempting to individualize treatment for patients with ovarian cancer, so that long-term outcomes may be improved.
Researchers from Italy recently conducted a clinical study to evaluate possible “markers” that may help predict which patients with ovarian cancer will or will not respond well to chemotherapy. This study included 52 women with ovarian cancer who were diagnosed with the same stage and cellular characteristics of cancer and were treated with the same surgery and chemotherapy regimens. At 2 years following surgery, 28 of these patients had died from progression of ovarian cancer. At 5 years following surgery, 24 patients were alive with no evidence of cancer. The researchers evaluated the cancers from each of these women in an attempt to detect similarities or differences within and between the 2 groups of patients that may be associated with improved responses to standard therapy. Both COX-2 expression and P-glycoprotein expression were significantly correlated with outcomes of these women. Overexpression of either of these agents was associated with reduced survival. COX-2 is associated with inflammatory responses in the body, and P-glycoprotein has been implicated in cancer cells not responding well to chemotherapy.
The researchers concluded that the level of expression of COX-2 and P-glycoprotein may predict for worse outcomes for women with advanced ovarian cancer treated with surgery and chemotherapy. Women with overexpression of these markers may benefit from frequent monitoring for a recurrence, or treatment other than surgery and chemotherapy. Future clinical trials are necessary to confirm the association between COX-2 and P-glycoprotein expression and outcomes of patients with ovarian cancer treated with surgery and chemotherapy.
Reference: Raspollini R, Amunni G, Villanucci A, et al. Increased cyclooxygenase-2 (COX-2) and P-glycoprotein-170 (MDR1) expression is associated with chemotherapy resistance and poor prognosis. Analysis in ovarian carcinoma patients with low and high survival. International Journal of Gynecologic