TY - JOUR AB - Neurofibromatosis type 1 (NF1) is one of the most commonly inherited autosomal dominant disorders. The malignant peripheral nerve sheath tumor (MPNST) is a major cause of mortality in patients with NF1. In this study, we found that overexpression of Bcl-xL in the established NF1-associated MPNST cell line and primary tissue cultured MPNST cells derived from an NF1 patient was closely associated with anticancer drug resistance of the NF1-associated MPNST cells. We demonstrated that high expression of Bcl-xL in the MPNST cells was caused by a decreased transcriptional expression of the NF1 gene. Downregulation of the NF1 gene by RNA interference (RNAi) induced an increase in Bcl-xL expression and a decrease in its sensitivity to apoptosis in the benign neurofibroma cell line and primary normal cells. These results suggest that an alteration of Bcl-xL expression levels by somatic expression changes in the NF1 locus may contribute to the malignant development of benign tumor tissues or normal tissues to MPNSTs. We further demonstrated that either depletion of Bcl-xL expression by RNAi or inactivation of Bcl-xL by ABT-737, a mimetic of the BH3-only protein BAD, was very effective in sensitizing the MPNST cells to apoptotic cell death by combined treatment with the tested anticancer drug doxorubicin. Notably, a low concentration of ABT-737 and doxorubicin could effectively induce synergistic cytotoxicity in the MPNST cells. These results suggest that pharmacological inhibition of Bcl-xL by ABT-737 in combination with doxorubicin can be a potential therapeutic strategy for the treatment of NF1-associated MPNSTs. AD - Department of Medical Genetics, School of Medicine, Ajou University, Suwon 443-721, Republic of Korea Department of Pathology, School of Medicine, Ajou University, Suwon 443-721, Republic of Korea AU - Lee,Su-Jin AU - Park,Ho-Jin AU - Kim,Young-Hwa AU - Kim,Bo-Young AU - Jin,Hyun-Seok AU - Kim,Hyon , J. AU - Han,Jae-Ho AU - Yim,Hyunee AU - Jeong,Seon-Yong DA - 2012/08/01 DO - 10.3892/ijmm.2012.1013 EP - 450 IS - 2 JO - Int J Mol Med KW - neurofibromatosis type 1 malignant peripheral nerve sheath tumor Bcl-xL apoptosis ABT-737 doxorubicin PY - 2012 SN - 1107-3756 1791-244X SP - 443 ST - Inhibition of Bcl-xL by ABT-737 enhances chemotherapy sensitivity in neurofibromatosis type 1-associated malignant peripheral nerve sheath tumor cells T2 - International Journal of Molecular Medicine TI - Inhibition of Bcl-xL by ABT-737 enhances chemotherapy sensitivity in neurofibromatosis type 1-associated malignant peripheral nerve sheath tumor cells UR - https://doi.org/10.3892/ijmm.2012.1013 VL - 30 ER -