[Growth suppression of colon cancer cells in vitro by DPC4 gene expression and its mechanism].
OBJECTIVE
To study the effect of DPC4 gene expression on the growth of colon cancer cells and its mechanism.


METHODS
Expression plasmid pcDNA3.1-DPC4 was constructed and transfected into the colon cancer cell line SW620 by use of lipofectamine gene transfer technique. DPC4 protein expression was detected by Western blot and immunocytochemistry. The effect of DPC4 gene on the growth of SW620 cells was monitored by population doubling time (PDT) and cloning efficiency. The influence of DPC4 expression on p21WAF1 transcription was investigated by RT-PCR to detect p21WAF1 mRNA.


RESULTS
Successful expression of DPC4 protein was detected in the transfected SW620 cells. Compared with the control cells, PDT (74 h) of the DPC4 expressing cells was prolonged and the cloning efficiency (21%) decreased. In addition, the mRNA level of p21(WAF1) in DPC4 transfected cells was increased.


CONCLUSIONS
Overexpression of DPC4 gene inhibits the growth of colon cancer in vitro, and induction of p21(WAF1) expression may be an important functional aspect of DPC4.
Liu
Yang
Y
Department of Pathology, Basic Medical School, Central South University, Changsha 410078, China.
Wen
Ji-Fang
JF
Li
Jing-He
JH
Xiao
De-Sheng
DS
Hu
Zhong-Liang
ZL
Luo
Geng-Qiu
GQ
D002277:Carcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics; D002455:Cell Division; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D050759:Cyclin-Dependent Kinase Inhibitor p21; D004268:DNA-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D018014:Gene Transfer Techniques; D016147:Genes, Tumor Suppressor; D006801:Humans; D051901:Smad4 Protein; D015534:Trans-Activators / Q000096:biosynthesis* / Q000235:genetics; D014162:Transfection; D014407:Tumor Cells, Cultured
C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D004268:DNA-Binding Proteins; C497796:SMAD4 protein, human; D051901:Smad4 Protein; D015534:Trans-Activators