Therefore, microRNA-206 upregulation in the MMTV group (Figure 6B) could be inhibiting the IGF1 signaling pathway corroborating to impair the performance in the maximal exercise test in sedentary breast cancer mice, even the body and skeletal mass, fiber number, cross-sectional area and function were still preserved (Figure 2D and Figure 4). Here, IGF1 is linked to breast carcinoma.