1. Correction to: Targeted therapy against Bcl-2-related proteins in breast cancer cells
- Author
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Ryungsa Kim, Yoko Uchida, Kazuaki Tanabe, Tetsuya Toge, and Manabu Emi
- Subjects
Oncology ,medicine.medical_specialty ,medicine.medical_treatment ,Transplantation, Heterologous ,bcl-X Protein ,Mice, Nude ,Tetrazolium Salts ,Antineoplastic Agents ,Apoptosis ,Breast Neoplasms ,lcsh:RC254-282 ,Targeted therapy ,Mice ,Breast cancer ,Surgical oncology ,Internal medicine ,Tumor Cells, Cultured ,Medicine ,Animals ,Humans ,business.industry ,Correction ,Oligonucleotides, Antisense ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,medicine.disease ,Genes, bcl-2 ,Thiazoles ,Proto-Oncogene Proteins c-bcl-2 ,Drug Resistance, Neoplasm ,Female ,Breast cancer cells ,business ,Research Article - Abstract
Introduction Bcl-2 and Bcl-xL confer resistance to apoptosis, thereby reducing the effectiveness of chemotherapy. We examined the relationship between the expression of Bcl-2 and Bcl-xL and chemosensitivity of breast cancer cells, with the aim of developing specific targeted therapy. Methods Four human breast cancer cell lines were examined, and the effects of antisense (AS) Bcl-2 and AS Bcl-xL phosphorothioate oligodeoxynucleotides (ODNs) on chemosensitivity were tested in vitro and in vivo. Chemosensitivity was evaluated by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay, and the antitumor effect was assessed in vivo by the success of xenograft transplantation into athymic mice. Results Treatment with AS Bcl-2 and Bcl-xL ODNs resulted in a sequence-specific decrease in protein expression, compared with controls. Treatment of BT-474, ZR-75-1, and MDA-MB-231 cells with AS Bcl-2 increased chemosensitivity to doxorubicin (DOX), mitomycin C (MMC), paclitaxel (TXL), and docetaxel (TXT). Transfection of the Bcl-2 gene into MDA-MB-453 cells decreased sensitivity to DOX and MMC. Treatment of MDA-MB-231, BT-474, and ZR-75-1 cells with AS Bcl-xL increased chemosensitivity to DOX, MMC and taxanes to a smaller extent than AS Bcl-2. This occurred in the setting of increased Bax and cleaved poly(ADP-ribose) polymerase, as well as decreased Bcl-2 and pAkt. AS Bcl-2 ODNs induced splenomegaly in association with increased serum IL-12, which was attenuated by methylation of the CpG motifs of AS Bcl-2; however, methylated CpG failed to negate the increased antitumor effect of AS Bcl-2. Bcl-2 and Bcl-xL, to a smaller extent, are major determinants of chemosensitivity in breast cancer cells. Conclusion Targeted therapy against Bcl-2 protein with the use of AS ODNs might enhance the effects of chemotherapy in patients with breast cancer.
- Published
- 2019