PDPK1 and exocrine pancreatic carcinoma: The two currently available drug discovery studies performed in pancreas cancer stem cell in vitro models using either a reporter line for the 26S proteasome activity of pancreas cancer cells or a 3D pancreatic carcinoma spheroid model yielded drug activities in the 3D CSC model with inhibition of phosphoinositide 3-kinase signaling, however there was an underrepresentation of selective PDPK1 inhibitors [62, 63].