Especially in gastric cancer, the following miRNAs (amongst others) have been found to substantially contribute to chemoresistance: let-7b, miRNA-106a, miRNA-142, miRNA-143, miRNA-21, miRNA-338, miRNA-340, miRNA-497, miRNA-503, and miRNA-582—their target genes including PTEN (phosphatase and tension homolog), BCL2 (B-cell lymphoma 2), and IGF1R (insulin-like growth factor 1 receptor) [18–25]. This evidence concerns the gene IGF1R and gastric cancer.