THE SYNERGISTIC EFFECTS OF HERCEPTIN AND 9-CIS-RETINOIC ACID ON HER2/NEU POSITIVE BREAST CANCER CELLS IN VIVO / 营养学报

ABSTRACT

Objective To observe the synergistic effects of Herceptin(HER)and 9-cis-retinoic acid (9-cis-RA) on HER2/neu positive breast cancer cells in vivo. Method MCF-7 breast cancer cells transfected with exogenous HER2 gene were inoculated into athymic nude mice. Four weeks after tumor inoculation,mice bearing a tumor of 200 mm3 in volume approximately were selected to be treated with HER and/or 9-cis-RA(SC) for 20d. After that tumor volume was precisely measured,concurrently the HE staining and Ki-67 immunohistochemical (IHC) assay were performed to detect the anti-proliferative effect of HER in combination with 9-cis-RA in vivo. Results After 3 w of treatment,HER and 9-cis-RA synergistically decreased the tumor volume as compared with control group. IHC results showed that Ki-67 expression was significantly inhibited by co-treatment of HER and 9-cis-RA,which means the arrest of cell cycle progression. Conclusion Herceptin and 9-cis-RA could synergistically inhibit the proliferation of HER2 positive breast cancer cells in vivo.