Effects of peptide nucleic acids against Ki-67 gene on the proliferation and apoptosis of human renal carcinoma cell line

Abstract

To investigate the effects of anti-sense peptide nucleic acids (PNAs) targeting Ki-67 gene on modulation of the proliferation and apoptosis of human renal carcinoma cell lines, human renal carcinoma cell line 786-0 cells were treated with anti-sense PNAs at different concentrations (1.0 mol/L, 2.0 mol/L, 10.0 mol/L). The Ki-67 expression of 786-0 cells was detected by immunohistochemical technique and Western blot method respectively. The proliferation of 786-0 cells was studied by cell growth curves and ³H-thymidine incorporation. The apoptosis of 786-0 cells was detected by TUNEL assay. The control groups were treated with anti-sense oligonucleotide (ASODNs) targeting Ki-67 gene. Our results showed that the Ki-67 expression of 786-0 cells treated with anti-sense PNAs (16.9±0.7) was significantly inhibited as compared with that of the control groups (28.6±0.4) (P<0.01). The Ki-67 protein rate of 786-0 cells treated with anti-sense PNAs (42.1±2.2) was significantly reduced when compared with that of the control groups (83.6±1.4) (P<0.01). Proliferation of 786-0 cells treated with anti-sense PNAs (20.7±1.5) was significantly inhibited as compared with that of the control groups (58.6±1.4) (P<0.01). The apoptosis rate of 786-0 cells treated with anti-sense PNAs (28.7±2.3) was significantly increased higher compared with that of the control groups (13.8±1.0) (P<0.01). From these finds we are led to conclude that anti-sense PNAs targeting Ki-67 gene have stronger effects on the inhibition of the proliferation and induction of apoptosis of human renal carcinoma cells than ASODNs targeting Ki-67 gene. The strategies using anti-sense PNAs targeting Ki-67 gene may be a promising approach for the treatment of renal cell carcinoma.

Keywords

peptide nucleic acid / antisense oligonucleotide / Ki-67 gene / renal cell carcinoma / proliferation / apoptosis

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