KRAS and cancer: This review describes (i) the historical background and experimental basis of the “oncogene” concept, (ii) the details of the discovery of the transforming viral and human KRas oncogenes along with HRas/Bas, and (iii) how the word “oncogene” was integrated into human cancer research literature as one of the most important keywords, according to PubMed database records (http://www.ncbi.nih.gov).