[Role of Bcl-xL in the cathepsin D-associated apoptosis of K562 cells].
The purpose of study was to explore the possible functions of Bcl-xL in the glucosamine sulfate-induced apoptosis of chronic myeloid leukemia K562 cells. Light microscopy and Wright-Giemsa staining were used to investigate the morphologic evidences for apoptosis of K562 cells induced by glucosamine sulfate (GS); immunofluorescence was used to observe the translocation of cathepsin D and cytochrome C during the apoptosis; Western blot was performed to detect the expression of Bcl-xL, Bid, Bax in K562 cells treated by GS. The results showed that many vacuoles were observed in the cytoplasma of the K562 cells treated by GS; fluorescent signals of cathepsin D and cytochrome were fransformed from granules to disperse form by using immunofluorescence; the expression of Bcl-xL was found down-regulated in K562 cells treated by GS, but not in the cells pre-treated with pepstatin A; the significant changes were not detected in expression of Bax and Bid protein before or after apoptosis. It is concluded that Bcl-xL protein may mediate relationship between cathepsin D and mitochondia pathway, Cathepsin D may play an important role in the GS inducing apoptosis of K562 cells through downregulation of Bcl-xL expression.
Department of Hematology, Xijing Hospital, The Fourth Military Medical University, Xi'an 710032, China.
Ying
Y
Piao
Li-Mei
LM
Liu
Xie-Qun
XQ
Chen
Rong
R
Liang
Gao-Sheng
GS
Huang
Yan
Y
Qiao
Ai-Qing
AQ
Wang
Zhe
Z
Wang
D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D051023:BH3 Interacting Domain Death Agonist Protein / Q000378:metabolism; D015153:Blotting, Western; D002402:Cathepsin D / Q000378:metabolism*; D045304:Cytochromes c / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005944:Glucosamine / Q000494:pharmacology; D006801:Humans; D020014:K562 Cells; D051028:bcl-2-Associated X Protein / Q000378:metabolism; D051020:bcl-X Protein / Q000378:metabolism / Q000502:physiology*
C494826:BAX protein, human; C494811:BCL2L1 protein, human; D051023:BH3 Interacting Domain Death Agonist Protein; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein; D045304:Cytochromes c; D002402:Cathepsin D; D005944:Glucosamine