[Apoptotic effect of the combined treatment of engineered antibody with paclitaxel on BT474 cells].

Aim: To explore the apoptotic effect of the combined treatment of anti-p185(c-erbB-2/neu) engineered antibody with paclitaxel on p185-overexpressing human malignant breast cancer cell lines BT474 and to study its emerging mechanism.

Methods: The prohibitory effect of engineeded antibody plus paclitaxel on BT474 cells was assessed by MTS assay. The number of apoptotic cells was detected by Annexin V-FITC/PI. DNA content and cell cycle distribution were determined by FCM; DNA-binding activity of NF-kappaB was demonstrated by EMSA.

Results: Anti-p185(c-erbB-2/neu) engineered antibody plus paclitaxel resulted in synergistic effect on proliferative inhibiton of BT474 cells, which was mediated via apoptotic induction and caused cell cycle to arrest at G1 phase remarkably. Furthermore, the combined treatment of the engineered antibody with paclitaxel effectively suppressed the activation of NF-kappaB in BT474 cells.

Conclusion: The combined treatment of anti-p185(c-erbB-2/neu) engineered antibody with paclitaxel rendered p185-overexpressing human malignant breast cancer cells BT474 more susceptible to paclitaxel-induced apoptosis by the effective suppression of NF-kappaB activation.