Fig. 1.

Derivation of metastatic variant prostate cancer cell lines and identification of 4.1B as a protein that is down-regulated in highly metastatic cells. (A) Highly metastatic #82 cells and poorly metastatic #78 cells were isolated after repeated in vivo passaging of PC-3 cells by using surgical orthotopic implantation. (B–D) #82 cells formed orthotopic primary tumors that exhibited an increased propensity to metastasize to paraaortic/lumbar lymph nodes (B), pararenal lymph nodes (C), and lung (D) relative to tumors from #78 cells (horizontal bar, mean). (E) Western blotting for 4.1B (Upper) or GAPDH loading control (Lower) confirmed gene expression analyses indicating that 4.1B was specifically down-regulated in highly metastatic #82 and PC-3M cells (F).