Apoptosis of human colon carcinoma HT-29 cells induced by ceramide.
OBJECTIVE
To investigate the effect of exogenous ceramide-induced apoptosis on human colon carcinoma HT-29 cells.


METHODS
Light microscope, transmission electron microscope and fluorescence microscope were used to observe the morphology change of apoptosis in HT-29 cells. Agarose gel electrophoresis was performed to detect the DNA fragment. Mitochondrial function was detected by MTT assay. mRNA expression of Bcl-2 family gene members was determined by reverse transcription polymerase chain reaction (RT-PCR) assay.


RESULTS
After C2-ceramide treatment, typical characteristics of apoptosis, such as nuclear chromatin breakage, apoptotic body and DNA ladder, could be observed. After exposure to 50 micromol/L C2-ceramide for 12 and 24 h, cell apoptosis was 64.1% and 81.3% respectively, which had a time-and dose-effect relationship. Mitochondrial function started to decrease from 6 h after exposure to ceramide. Meanwhile, ceramide up-regulated or down-regulated the mRNA expression of Bcl-2 family gene members.


CONCLUSIONS
Ceramide induces apoptosis of human colon carcinoma HT-29 cells by affecting the expression of Bcl-2 family gene members and impacting the mitochondrial function.
Zhang
Xiao-Feng
XF
Department of Toxicology, Public Health College, Harbin Medical University, 157 Baojian Road, Nangang District, Harbin 150081, Heilongjiang Province, China.
Li
Bai-Xiang
BX
Dong
Chun-Yan
CY
Ren
Rui
R
D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000235:genetics / Q000473:pathology* / Q000648:ultrastructure; D053938:DNA Fragmentation; D004273:DNA, Neoplasm / Q000187:drug effects / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D019254:Genes, bcl-2 / Q000235:genetics; D006801:Humans; D008928:Mitochondria / Q000187:drug effects; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000494:pharmacology
D004273:DNA, Neoplasm; D004791:Enzyme Inhibitors; C064769:N-acetylsphingosine; D012333:RNA, Messenger; D013110:Sphingosine