Similar to the effects of miR-375 overexpression, silencing of IGF1R partially restored the sensitivity of SKBr-3 cells to trastuzumab (p < 0.01, Figure 3F and G), suggesting that IGF1R, as a target gene of miR-375, is critically involved in trastuzumab resistance of breast cancers. This evidence concerns the gene IGF1R and breast carcinoma.