Concurrent induction of necrosis, apoptosis, and autophagy in ischemic preconditioned human livers formerly treated by chemotherapy.
OBJECTIVE
Liver pathology induced by chemotherapy (steatosis or vascular injury) is known to increase the liver's sensitivity to ischemia/ reperfusion (I/R) injury, thereby increasing morbidity and mortality after liver resection. Our aim was to assess whether ischemic preconditioning (IP) reduces I/R injury to livers with chemotherapy-induced pathology.


METHODS
We analyzed a series of livers from patients treated with chemotherapy for colorectal cancer who underwent IP (n=30) or not (n=31) before hepatectomy. All but one of the livers exhibited chemotherapy-induced steatosis and/ or peliosis before the I/R insult.


RESULTS
Necrosis was less frequent (p=0.038) in livers with IP than in the others. IP had no influence on apoptosis as assessed by terminal transferase uridyl nick-end labeling (TUNEL) assay or caspase-3, -8 and -9 expression. IP induced a twofold increase in B-cell leukemia/ lymphoma 2 (Bcl-2; p<0.05), which was localized to hepatocytes of centrolobular and peliotic areas and colocalized with the autophagy protein beclin-1 in livers with IP, suggesting their coordinated role in autophagy. Increased expression of the phosphorylated Bcl-2 was observed in preconditioned livers and was associated with a decreased immunoprecipitation of beclin-1 and the increased expression of light chain 3 type II (LC3-II). The increased number of autophagic vacuoles seen by electron microscopy confirmed an association of autophagy in chemotherapy-injured livers following IP. However, the differences in protein expression were not reflected in postresection liver-injury tests or measure of patient morbidity.


CONCLUSIONS
IP is associated with a reduction in necrosis of hepatocytes already damaged by chemotherapy and an activation of autophagy. Bcl-2 and beclin-1 could be major targets in the regulation of cell death during I/R injury.
Domart
Marie-Charlotte
MC
AP-HP, Hôpital Paul Brousse, Service de Biochimie et Biologie Moléculaire, Villejuif, France.
Esposti
Davide Degli
DD
Sebagh
Mylène
M
Olaya
Natalia
N
Harper
Francis
F
Pierron
Gérard
G
Franc
Brigitte
B
Tanabe
Kenneth K
KK
Debuire
Brigitte
B
Azoulay
Daniel
D
Brenner
Catherine
C
Lemoine
Antoinette
A
D000368:Aged; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D001343:Autophagy; D000071186:Beclin-1; D015179:Colorectal Neoplasms / Q000188:drug therapy; D005260:Female; D006801:Humans; D019194:Ischemic Preconditioning; D008099:Liver / Q000098:blood supply* / Q000293:injuries / Q000378:metabolism / Q000473:pathology*; D008113:Liver Neoplasms / Q000188:drug therapy / Q000556:secondary / Q000601:surgery; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D008875:Middle Aged; D009336:Necrosis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D015427:Reperfusion Injury / Q000517:prevention & control
D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; D008565:Membrane Proteins; D019253:Proto-Oncogene Proteins c-bcl-2