miR-135b-5p is an oncogene that negatively regulates KLF4 expression by direct binding to its 3′UTR region, resulting in reduced levels of KLF4 and activation of G protein-coupled receptor class C group 5-member A (GPRC5A), and promoting the malignant progression of pancreatic cancer [104]. This evidence concerns the gene KLF4 and familial pancreatic carcinoma.