Taxane-based adjuvant chemotherapy reduces endothelin-1 and symmetric dimethylarginine levels in patients with breast cancer.

Purpose: To evaluate the levels of asymmetric dimethylarginine (ADMA), an endothelin and nitric oxide (NO) synthase inhibitor, in patients with node-positive breast cancer who had undergone surgery and in a control group including healthy individuals. The effects of taxane-based chemotherapy on endothelin-1 (ET-1) and ADMA levels in the patient group were also studied.

Methods: Body mass index (BMI), serum lipids (total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides), ADMA and ET-1 were studied in 19 healthy individuals and in 19 patients with stage II and III, lymph node-positive breast cancer receiving taxane-based chemotherapy.

Results: ET-1 (34.3±12.8 vs. 13.8±4.5 pg/mL; p<0.001) and ADMA (0.87±0.18 vs. 0.68±0.24 μmol/L; p=0.024) levels were significantly higher in the breast cancer group compared to the control group. A significant reduction was noted in ET-1 (34.3±12.8 vs. 27.3±4.3 pg/mL; p=0.021) and ADMA (0.87±0.18 vs. 0.73±0.15 μmol/L; p=0.014) levels in patients following 6 cycles of adjuvant chemotherapy to baseline values.

Conclusion: The present study demonstrated significantly higher levels of ET-1 and ADMA in the breast cancer group compared to the control group, which were reduced significantly with adjuvant taxane-based chemotherapy. It is apparent that prospective studies are needed to understand the effect of reducing ET-1 and ADMA levels on patient survival. We believe that the present study will provide guidance to relevant future studies.