Apoptotic effects of psiRNA-STAT3 on 4T1 breast cancer cells in vitro

Asian Pac J Cancer Prev. 2014;15(16):6977-82. doi: 10.7314/apjcp.2014.15.16.6977.

Abstract

Background: The aim of this study was to investigate the effect of a Lipofectamine2000 (Life2000) Transfection Reagent transfected psiRNA-STAT3 plasmid on 4T1 breast cancer cells.

Materials and methods: MTT was used to detect the cell proliferation of breast cancer 4T1 cells at different periods (0h, 6h, 8h, 10h); the cell cycle was assessed by flow cytometry; variation of apoptosis and mitochondrial membrane potential was observed under a fluorescence microscope; immunohistochemical staining was used to determine the expression of caspase-3 and cyclin-D1 protein.

Results: An obvious effect of inhibition to 4T1 cancer cells could be observed at 8h after the psiRNA-STAT3 was transfected. Typical alterations of apoptotic morphological features were visible in the psiRNA-STAT3 treatment group. Mitochondrial membrane potential decreased significantly, the number of cells was increased in G0/G1 phase, and the number of cells was decreased in S phase, and the data were statistically significant (p<0.05), compared with the Scramble and Mock groups. Expression of caspase-3 protein was increased significantly, while that of cyclin D1 was significantly decreased.

Conclusions: Life2000 transfected psiRNA-STAT3 plasmid can inhibit 4T1 tumor cell proliferation and promote apoptosis of 4T1 tumor cells, which process depends on the regulation of expression of cyclin D1 and caspase-3 protein.

MeSH terms

  • Animals
  • Apoptosis / genetics*
  • Breast Neoplasms / genetics*
  • Caspase 3 / biosynthesis
  • Cell Line, Tumor
  • Cell Proliferation / genetics*
  • Cyclin D1 / biosynthesis
  • Female
  • G1 Phase Cell Cycle Checkpoints / genetics
  • Lipids / administration & dosage
  • Membrane Potential, Mitochondrial / genetics*
  • Mice
  • RNA, Small Interfering / genetics
  • S Phase Cell Cycle Checkpoints / genetics
  • STAT3 Transcription Factor / administration & dosage
  • STAT3 Transcription Factor / genetics*
  • Transfection / methods

Substances

  • Lipids
  • Lipofectamine
  • RNA, Small Interfering
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • Cyclin D1
  • Caspase 3