title: BAG3 promoted starvation-induced apoptosis of thyroid cancer cells via attenuation of autophagy.
abstract: BACKGROUND
  BAG3 plays a regulatory role in a number of cellular processes. Recent studies have attracted much attention on its role in activation of selective autophagy. In addition, we have very recently reported that BAG3 is implicated in a BECN1-independent autophagy, namely noncanonical autophagy.
  
  
  OBJECTIVE
  The current study aimed to investigate the potential involvement of BAG3 in canonical autophagy triggered by Earle's Balanced Salt Solution (EBSS) starvation.
  
  
  METHODS
  Replacement of complete medium with EBSS was used to trigger canonical autophagy. BAG3 expression was measured using real-time RT-PCR and Western blot. Autophagy was monitored using LC3-II transition and p62/SQSTM1 accumulation by Western blot, as well as punctate distribution of LC3 by immunofluorescence staining. Cell growth and apoptotic cell death was investigated using real-time cell analyzer and flowcytometry, respectively.
  
  
  RESULTS
  BAG3 expression was potently reduced by EBSS starvation. Forced expression of BAG3 suppressed autophagy and promoted apoptotic cell death of thyroid cancer cells elicited by starvation. In addition, in the presence of autophagy inhibitor, the enhancing effect of BAG3 on apoptotic cell death was attenuated.
  
  
  CONCLUSIONS
  These results suggest that BAG3 promotes apoptotic cell death in starved thyroid cancer cells, at least in part by autophagy attenuation.
authors: Departments of Endocrinology and Metabolism (S.L., T.W., Z.-X.D.), Geriatrics (H.-Y.Z.), and Biochemistry and Molecular Biology (X.M., Z.-H.Z., D.-H.K., H.-Q.W.), the First Affiliated Hospital, China Medical University, Shenyang 110001, China.
authors: Si
authors: S
authors: Li
authors: Hai-Yan
authors: HY
authors: Zhang
authors: Tian
authors: T
authors: Wang
authors: Xin
authors: X
authors: Meng
authors: Zhi-Hong
authors: ZH
authors: Zong
authors: De-Hui
authors: DH
authors: Kong
authors: Hua-Qin
authors: HQ
authors: Wang
authors: Zhen-Xian
authors: ZX
authors: Du
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D001343:Autophagy / Q000187:drug effects / Q000502:physiology*; D002453:Cell Cycle / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects / Q000502:physiology; D003470:Culture Media; D006801:Humans; D012492:Salts / Q000494:pharmacology*; D013961:Thyroid Gland / Q000378:metabolism* / Q000473:pathology; D013964:Thyroid Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; C414431:BAG3 protein, human; D003470:Culture Media; D012492:Salts