Leptin, insulin and body composition changes during adjuvant taxane based chemotherapy in patients with breast cancer, preliminary study.

BACKGROUND: The objectives of the present study were to compare the effect of adjuvant chemotherapy for breast cancer on serum insulin levels, serum leptin levels, and body composition in early stage breast cancer patients. MATERIALS AND METHODS: 17 breast cancer patients underwent 6 cycles of docetaxel (75 mg), epirubicine (100 mg) and cyclophosphamide (500 mg) (TEC). Anthropometrical and foot-to-foot body fat analyzer BIA, serum glucose, insulin, lipids, HOMA-IR and leptin were compared pre- and post-treatment. RESULTS: There was no statistically significant weight gain after treatment; however, there was an overall trend toward weight gain (69.7 ± 9.8 kg vs 71.03 ± 9.8; P= 0.05). From baseline to the end of the study, percentage of body fat and body fat mass showed an upward trend at the end of chemotherapy (1%; 2 kg P> 0.05). Pre and post-treatment period, leptin was strongly correlated with insulin and HOMA-IR (Spearman's pre-T; r = 0.74; P <0.001, r = 0.66; P = 0.004 post-T; r = 0.549; P =0.022, r = 0.51; P =0.036, respectively). Insulin levels were significantly increased in the post-treatment period (P < 0.05). On correlation analysis, post-T insulin levels were correlated with leptin, weight, fat-mass and fat percentage (Spearman's r = 0.549; P=.022, r = 0.567; P= 0.018, r = 0.498, P= 0.042, r = 0.502; P= 0.040, respectively). DISCUSSION: High insulin and leptin levels, important factors that were previously shown to be related to breast cancer outcome, and insulin resistance may be increased in taxane based chemotherapy regimen. These data may have broad implications for diet and lifestyle strategies for the prevention and treatment of cancers.

Oxidative and antioxidative status after anthracyclinebased chemotherapy in breast cancer patients.

PURPOSE: The present study was undertaken to evaluate the effects of adjuvant anthracycline-based chemotherapy on thiobarbituric acid reactive substances (TBARS) and superoxide dismutase (SOD) levels in patients with breast cancer who had undergone surgery. METHODS: Body mass index (BMI), serum lipids (total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides), serum TBARS and SOD values were assessed in 30 patients with stage III breast cancer receiving adjuvant anthracycline- based chemotherapy. RESULTS: Anthracycline-based chemotherapy had no effect on BMI, blood pressure and lipid profile. A significant elevation was noted in TBARS (5.5±0.6 vs 5.9±0.9 µmol/L; p=0.038) and a significant reduction to baseline values in SOD levels (226.5±61.0 vs 203.1±48.3 U/mL; p=0.03) in patients following 6 cycles of adjuvant chemotherapy. CONCLUSION: The TBARS levels increased, whereas the SOD levels descreased after anthracycline-based chemotherapy. We suggest that oxidative stress is not always detrimental, as it can be beneficial in cancer treatment.

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.