Pancreatic cancer develops through ductal dysplastic lesions or pancreatic intraepithelial neoplasia (PanIN). The origin of pancreatic cancer remains controversial. Some of the molecular origins of pancreatic cancer have been described. For example, KRAS, SHH, CDKN2A, TP53, SMAD4, and DUSP6 are crucial molecules in the development and progression of pancreatic cancer. Understanding the mechanisms of carcinogenesis could help researchers find the Achilles' heel of pancreatic cancer. Molecular targeting is a promising strategy for curing this devastating disease.