Expression of survivin in human lung cancer and the influence of its down-regulation on biological behavior of this cancer

摘要

The aim of our study was to detect the expression of survivin in human lung cancer and the influence of its down-regulation on biological behavior of lung cancer A549 cell. The high expression of survivin in human lung cancer was verified by immunohistochemistry (IHC) method. Survivin-siRNA (small interfering RNA) and unrelated sequence were synthesized and siRNA lentiviral vector was then constructed. The vector was then transfected into lung cancer A549 cell, in which the clone with stable expression was screened out. We blocked the expression of survivin mRNA and protein by RNA interference (RNAi) technique. The down-regulation of survivin mRNA and protein expression was determined by real-time quantitative PCR (RT-qPCR) and Western blot. The proliferating activity and growth speed of A549 cell were determined by colony formation assay (CFA) and mono-nuclear cell direct cytotoxicity assay (MTT Assay). The GBM penetrating capacity was determined by cell invasion assay. The cell movement and migration capacity were detected by erasion trace test. The results showed that the sequence-specific siRNA significantly down-regulated the expression of survivin at both mRNA and protein levels. Down regulation of survivin expression dramatically decreased the invasive and metastatic capacities of the cell, suppressed the proliferation, decelerated the speed of growth, reduced the number of clones on soft agar and decreased the capacity of GBM penetrating and migration. In conclusion, Survivin, which played an important role in carcinogenesis and development of lung cancer, could be effectively down-regulated by RNAi technique.