[Effect of DAPK1 gene transfection on high-metastasis non-small lung cancer cell PGCl3]
Hai-Tao Zhang1, Zhen-Yu Zhu, Zhe-Ling Feng
1Department of Biochemistry, Sun Yat-sen Medical College, Sun Yat-sen University, Guangzhou, Guangdong, 510089, PR China.
Background & Objective:
Loss of activity of death- associated protein kinase 1 (DAPK1) may be an independent factor affecting survival of non-small cell lung cancer patients. DAPK1 over-expression can induce cell apoptosis and inhibit tumor cell metastasis. However, the mechanism of DAPK1 inhibiting metastasis was unclear yet. This study was designed to investigate the mechanism of DAPK1 affecting PGCl3 cells' growth and metastasis.
Methods:
Open read frame (ORF) of DAPK1 gene was recombined into eukaryotic express vector pcDNA3.1. The PGCl3 cell line, a high metastasis lung tumor cell line, was transfected with pcDNA3.1-DAPK1 by lipofectamine2000. The growth curve of PGCl3 cells, colony formation assays, invasive, migration and adhesion ability were evaluated. Gelatinase secretion of PGCl3 cells treated with DAPK1 and expression of p53 and bcl-2 gene in PGCl3 cells were determined.
Results:
PGCl3 cells of pcDNA3.1-DAPK1-transfected group grew slower than blank group and pcDNA3.1-transfected group. The numbers of colony formation of pcDNA3.1-DAPK1-transfected group reduced in comparison with blank group and pcDNA3.1-transfected group (P< 0.05). Invasive ability of pcDNA3.1-DAPK1-transfected group was 68.5% to blank group, and pcDNA3.1-transfected group was 88% to blank group. Migration ability of pcDNA3.1-DAPK1-transfected group was 87.3% to blank group and pcDNA3.1-transfected group was 95.7% to blank group. Adhesion ability of pcDNA3.1-DAPK1-transfected group was 62.7% to blank group, and pcDNA3.1-transfected group was 91.2% to blank group. Changes in PGCl3 cells secreting gelatinase have not been observed in different groups. Expression of p53 gene was upregulated in pcDNA3.1-DAPK1-transfected group, while expression of bcl-2 gene was downregulated.
Conclusion:
DAPK1 gene over-expression could suppress PGCl3 cells malignant phenotype, inhibit PGCl3 cells growth, invasive, migration and adhesion ability, upregulate p53 gene and downregulate bcl-2 gene. All of these changes may be the mechanism of inhibition of non-small cell lung cancer metastasis induced by DAPK1.
