In the colony-formation assay, upon low-density seeding, colony numbers of sh-L1-B- and sh-L1-E-expressing PC3 cells were 30±4.6 and 44±2.2 with respective inhibition ratios of 23% and 48% (p<0.01) compared to control shRNA-expressing cells (Fig. 5B), which further reveals a function of the L1CAM in supporting cell contact-dependent growth of tumor cells. This evidence concerns the gene L1CAM and neoplasm.