ANTXR1 and neoplasm: While PA, and also tumor-selective PA variants cleaved by other proteases alone (without LF or cytotoxic LFn fusion proteins), are not cytotoxic to a variety of cell lines, it was reported that recombinant CHO cell lines overexpressing TEM8 (CHO-TEM8) are sensitive towards PA without any LF or LFn fusion protein [51].