Effects of the knockdown of death-associated protein 3 expression on cell adhesion, growth and migration in breast cancer cells.
The death-associated protein 3 (DAP3) is a highly conserved phosphoprotein involved in the regulation of autophagy. A previous clinical study by our group suggested an association between low DAP3 expression and clinicopathological parameters of human breast cancer. In the present study, we intended to determine the role of DAP3 in cancer cell behaviour in the context of human breast cancer. We developed knockdown sub-lines of MCF7 and MDA-MB-231, and performed growth, adhesion, invasion assays and electric cell-substrate impedance sensing (ECIS) studies of post-wound migration of the cells. In addition, we studied the mRNA expression of caspase 8 and 9, death ligand signal enhancer (DELE), IFN-β promoter stimulator 1 (IPS1), cyclin D1 and p21 in the control and knockdown sub-lines. The knockdown sub-lines of MCF7 and MDA-MB-231 had significantly increased adhesion and decreased growth when compared to the controls. Furthermore, invasion and migration were significantly increased in the MDA-MB-231DAP3kd cells vs. the controls. The expression of caspase 9 and IPS1, known components of the apoptosis pathway, were significantly reduced in the MCF7DAP3kd cells (p=0.05 and p=0.003, respectively). We conclude that DAP3 silencing contributes to breast carcinogenesis by increasing cell adhesion, migration and invasion. It is possible that this may be due to the activity of focal adhesion kinase further downstream of the anoikis pathway. Further research in this direction would be beneficial in increasing our understanding of the mechanisms underlying human breast cancer.
The London Breast Institute, Princess Grace Hospital, London, UK.
Umar
U
Wazir
Cardiff University-Peking University Cancer Institute (CUPUCI), Cardiff University School of Medicine, Cardiff University, Cardiff, Wales, UK.
Andrew J
AJ
Sanders
Peshawar Medical College, Peshawar, Pakistan.
Ahmad M A
AM
Wazir
Cardiff University-Peking University Cancer Institute (CUPUCI), Cardiff University School of Medicine, Cardiff University, Cardiff, Wales, UK.
Lin
L
Ye
Cardiff University-Peking University Cancer Institute (CUPUCI), Cardiff University School of Medicine, Cardiff University, Cardiff, Wales, UK.
Wen G
WG
Jiang
Department of Breast Surgery, St. George's Hospital and Medical School, University of London, London, UK.
Irina C
IC
Ster
Department of Breast Surgery, St. George's Hospital and Medical School, University of London, London, UK.
Anup K
AK
Sharma
The London Breast Institute, Princess Grace Hospital, London, UK.
Kefah
K
Mokbel
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics; D017209:Apoptosis / Q000235:genetics; D051017:Apoptosis Regulatory Proteins / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D053181:Caspase 8 / Q000235:genetics; D053453:Caspase 9 / Q000235:genetics; D002448:Cell Adhesion / Q000235:genetics*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics*; D049109:Cell Proliferation / Q000235:genetics*; D019938:Cyclin D1 / Q000235:genetics; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics; D005260:Female; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D006801:Humans; D061986:MCF-7 Cells; D024101:Mitochondrial Proteins / Q000235:genetics; D009361:Neoplasm Invasiveness / Q000235:genetics / Q000473:pathology; D016601:RNA-Binding Proteins; D012269:Ribosomal Proteins / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics
D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; C097041:DAP3 protein, human; C554526:DELE1 protein, human; C505371:MAVS protein, human; D024101:Mitochondrial Proteins; D016601:RNA-Binding Proteins; D012269:Ribosomal Proteins; D019938:Cyclin D1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D053181:Caspase 8; D053453:Caspase 9