Among those genes associated with DNA repair, twelve genes (BRCA1, DMC1, EXO1, FANCG, FEN1, MSH2, PRKDC, RAD18, RAD51B, p73, UNG, and XRCC2) were differentially expressed in the LS-174T tumor xenografts following Gem/212Pb-trastuzumab and Gem/212Pb-HuIgG treatments. The gene discussed is RAD18; the disease is neoplasm.