Moreover, the fact that expressing a dominant negative form of the CD43 molecule in the lung-derived tumor cell line A549 prevented cell motility and anchorage-independent growth, and that only a few colonies expressing the CD43 mutant molecule were recovered as opposed to when the empty vector was transfected (4 versus150), points to a role for CD43 signals in the proliferation and survival of lung-derived tumor A549 cells. This evidence concerns the gene SPN and neoplasm.