Based on the tumor suppressor role of KLF4 in cancer of various epithelial tissues and the reported oncogenic activity for miR-7 in epithelial lung carcinoma and epithelial RCC; we hypothesized that during the transformation process of epithelial cells, the negative regulation of KLF4 by miR-7 results in a carcinogenic process. This evidence concerns the gene KLF4 and neoplasm.