[Changes of expression and sequence of ERCC1 in cadmium chloride-induced transformed 16HBE cells at different stages].
OBJECTIVE
To explore the expression and sequence of ERCC1 gene in CdCl2-induced transformed human bronchial epithelial 16HBE cells at different stages.


METHODS
Reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemcial staining (SP method) were used to measure the ERCC1 mRNA and protein expression in 16HBE cells at different passages treated with CdCl2 (the 5th, 15th, 35th passage, and neoplastic cells from tumors formed in nude mice). ERCC1 exon 3,exon 4 of the 16HBE cells and tumor cells from nude mice were amplified by polymerase chain reactions (PCR), the amplified DNA strips were purified,and the exons were detected by DNA analysis.


RESULTS
During the passages of 16HBE cells treated with CdCl2, the expression of ERCC1 gene was decreased gradually. The ERCC1 gene mRNA and protein expression levels of the CdCl2-transformed 35th passage 16HBE cells and tumor cells from nude mice were significantly decreased comparing with those in non-transformed 16HBE cells (P < 0.01). In the CdCl2-induced tumorigenic cells in nude mice, there was adenine (A) deletion in 1st site of ERCC1 exon 4. The mutation was frame shift mutation.


CONCLUSIONS
The decreased expression and mutation of ERCC1 gene may be the possible carcinogenic mechanism of CdCl2.
Zhou
Zhi-Heng
ZH
School of Public Health and General Medicine, Guangzhou Medical College, Guangzhou 510182, China.
Lei
Yi-Xiong
YX
Wang
Cai-Xia
CX
Wang
Min
M
Wei
Lian
L
D000818:Animals; D001980:Bronchi / Q000166:cytology; D019256:Cadmium Chloride / Q000633:toxicity*; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004720:Endonucleases / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism; D005091:Exons; D016368:Frameshift Mutation; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D012333:RNA, Messenger / Q000378:metabolism
D004268:DNA-Binding Proteins; D012333:RNA, Messenger; C071447:ERCC1 protein, human; D004720:Endonucleases; D019256:Cadmium Chloride