[Effects of cigarette smoke extract on the proliferation and the expression of TGF-beta1 and EGF in human embryonic lung fibroblasts].
OBJECTIVE
To observe the effects of cigarette smoke extract (CSE) on the proliferation and the expression of TGF-beta(1) and EGF in human embryonic lung fibroblasts (HELF).


METHODS
The cultures of HELF were incubated with CSE (1:50, 1:25 and 1:10) for examining the effects of CSE on the proliferation and the proliferating cell nuclear antigen (PCNA) levels in HELF. The total RNA was extracted from the cells incubated with CSE at different doses. The expression levels of TGF-beta(1) mRNA were evaluated by reverse transcription-polymerase chain reaction (RT-PCR). The mRNA levels of TGF-beta(1) were corrected by GAPDH transcripts. TGF-beta(1) and EGF protein levels were determined by immunocytochemistry.


RESULTS
The proliferation of HELF was inhibited by CSE in a dose-dependent manner. CSE also decreased the PCNA levels of HELF at all doses (P < 0.05). CSE stimulated TGF-beta(1) mRNA and protein expression of HELF at lower concentrations (1:50 and 1:25, P < 0.05). TGF-beta(1) mRNA and protein production were not increased by CSE at a higher concentration (1:10, P > 0.05). Decreased expression of EGF protein was observed in HELF treated by CSE (1:25 and 1:10, P < 0.05).


CONCLUSIONS
CSE can inhibit the proliferation of HELF and the effect may involve the abnormal expression of TGF-beta(1) and EGF in HELF.
Ge
Xiao-na
XN
Department of Pathology, Tongji Medical College, Huazhong Sciences and Technology University, Wuhan 430030, China.
Xiong
Mi
M
Huang
Zhao
Z
D002455:Cell Division; D002478:Cells, Cultured; D004815:Epidermal Growth Factor / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D008168:Lung / Q000166:cytology / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012906:Smoke; D014026:Nicotiana; D016212:Transforming Growth Factor beta / Q000235:genetics* / Q000378:metabolism; D053773:Transforming Growth Factor beta1
D012906:Smoke; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D004815:Epidermal Growth Factor