ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of antibody-targeted chemotherapy against human prostate cancer LNCaP cells in vitro.</p><p><b>METHODS</b>The monoclonal antibody 7E11C5.3 against human prostate cancer was conjugated to pingyangmycin (PYM), mediated by dextran T-40, and the immunoreactivity of 7E11C5.3 was determined by indirect enzyme-linked immunosorbent assay. The bacteriostatic activity of the conjugate was determined using TTC assay, and its cytotoxicity against LNCaP cells was determined by MTT assay.</p><p><b>RESULTS</b>The 7E11C5.3:PYM molar ratio was l:54 in the conjugate, and the immunoreactivity of 7E11C5.3 was decreased by approximately 10% to 20% after conjugation. The bacteriostatic activity of conjugated PYM was 25% of that of free PYM. The 50% inhibitory doses (IC50) of 7E11C5.3-PYM conjugate and free PYM against the in vitro cultured LNCaP cells were 9.41-/+1.98 microg/ml and 29.92-/+7.88 microg/ml, respectively.</p><p><b>CONCLUSION</b>7E11C5.3-PYM conjugate displays stronger cytotoxicity against anti-prostate cancer effects than free PYM.</p>