The effect of 8 weeks of aerobic training on Apaf-1 and Caspase 3 gene expression in mice with breast cancer

Considering the key role of apoptosis and other factors in inflammation, growth and metastasis of tumor cells and also regulating effect of physical activity, the aim of this study was to investigate the effects of aerobic exercise on the expression of these factors in breast cancer and also on breast cancer tumors weight reduction in mice.

Twenty female 3-weeks-old C ball mice with a mean weight of 17.10 ±0.10 g were randomly divided into experimental (aerobic exercise) and control groups. By subcutaneous injection of MC4-L2 cancer cells, both groups were diagnosed with cancer, and then the experimental group was trained for 8 weeks (5 sessions per week and each session lasted 14-20 minutes running at 55-70 percent of VO2max on the treadmill with zero gradient. The exercises began at a speed of 14 m/min in the first week and finally reached to 20 m/min in the last two weeks. 48 hours after the last training session, the mice were sacrificed and their tumors tissue samples were removed and stored at -70 ° C and the level of gene expression of Apaf-1 and caspase 3 of tumor tissue were measured by Real Time-PCR. Data were analyzed by SPSS21 using independent sample t- test at the significant level of p≤0.05.

The results of independent sample t- test showed that tumor volume in the training group was significantly lower than the control group (p=0.001), moreover the levels of Apaf-1 (p=0.001) and caspase 3 (p=0.001) was also significantly higher than the control group.

Due to the increased gene expression of Apaf-1 and caspase 3 following regular aerobic exercise with intensity of 55 to 70% VO2max, it can be suggested that medium-intensity aerobic exercise can controls the growth of breast tumors in female Balb C mice.