PTHLH and neoplasm: To evaluate the effects of PTHLH re-expression on tumor growth in vitro, we knock-down endogenous PTHLH and then reintroduced lentivirus-mediated vector (LV-Ctrl) and PTHLH using lentivirus-mediated PTHLHGFP (LV-PTHLHRE) to examine whether the re-expression of PTHLH could rescue the retarded proliferation (Additional file 1: Figure S2D).