TY - JOUR
T1 - HMGB1 promotes drug resistance in osteosarcoma
AU - Huang, Jun
AU - Ni, Jiangdong
AU - Liu, Ke
AU - Yu, Yan
AU - Xie, Min
AU - Kang, Rui
AU - Vernon, Philip
AU - Cao, Lizhi
AU - Tang, Daolin
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/1/1
Y1 - 2012/1/1
N2 - Osteosarcoma is the most commonly occurring bone cancer in children and adolescents. Unfortunately, treatment failures are common due to the development of chemoresistance, for which the underlying molecular mechanisms remain unclear. In this study, we implicate the DNA-binding protein HMGB1, which also exerts immunoregulatory effects in its secreted form, in the development of drug resistance in osteosarcoma. Anticancer agents including doxorubicin, cisplatin, and methotrexate each induced HMGB1 upregulation in human osteosarcoma cells, and RNA interference-mediated knockdown of HMGB1 restored the chemosensitivity of osteosarcoma cells in vivo and in vitro. Mechanistic investigation revealed that HMGB1 increased drug resistance by inducing autophagy, an intracellular self-defense mechanism known to confer drug resistance. We found that HMGB1 bound to the autophagy regulator Beclin1 and regulated the formation of the Beclin1-PI3KC3 [PI3KC3, phosphatidylinositol 3-kinase class 3] complex that facilitates autophagic progression. In addition, we found that interaction between HMGB1 and Beclin1 relied upon the autophagic complex ULK1-mAtg13-FIP200. Therefore, through its role as a regulator of autophagy, HMGB1 is a critical factor in the development of chemoresistance, and it offers a novel target for improving osteosarcoma therapy.
AB - Osteosarcoma is the most commonly occurring bone cancer in children and adolescents. Unfortunately, treatment failures are common due to the development of chemoresistance, for which the underlying molecular mechanisms remain unclear. In this study, we implicate the DNA-binding protein HMGB1, which also exerts immunoregulatory effects in its secreted form, in the development of drug resistance in osteosarcoma. Anticancer agents including doxorubicin, cisplatin, and methotrexate each induced HMGB1 upregulation in human osteosarcoma cells, and RNA interference-mediated knockdown of HMGB1 restored the chemosensitivity of osteosarcoma cells in vivo and in vitro. Mechanistic investigation revealed that HMGB1 increased drug resistance by inducing autophagy, an intracellular self-defense mechanism known to confer drug resistance. We found that HMGB1 bound to the autophagy regulator Beclin1 and regulated the formation of the Beclin1-PI3KC3 [PI3KC3, phosphatidylinositol 3-kinase class 3] complex that facilitates autophagic progression. In addition, we found that interaction between HMGB1 and Beclin1 relied upon the autophagic complex ULK1-mAtg13-FIP200. Therefore, through its role as a regulator of autophagy, HMGB1 is a critical factor in the development of chemoresistance, and it offers a novel target for improving osteosarcoma therapy.
UR - http://www.scopus.com/inward/record.url?scp=84855406005&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84855406005&partnerID=8YFLogxK
U2 - 10.1158/0008-5472.CAN-11-2001
DO - 10.1158/0008-5472.CAN-11-2001
M3 - Article
C2 - 22102692
AN - SCOPUS:84855406005
VL - 72
SP - 230
EP - 238
JO - Cancer Research
JF - Cancer Research
SN - 0008-5472
IS - 1
ER -