[Inhibition of A549 cells by polybutylcyanoacrylate nanoparticles loaded with antisense oligodeoxynucleotide of hTERT mRNA].

Aim: To investigate the effect of nanoparticles for antisense oligodeoxynucleotide (ASODN) of hTERT mRNA on A549 cells.

Methods: The cationic polybutylcyanoacrylate nanoparticles (NPs) were prepared by an emulsion polymerization process in the presence of DEAE-dextran. Antisense oligodeoxynucleotides were loaded on the particles by adsorption. The cytotoxicity of NPs and proliferation of A549 cells were detected by MTT assay. Intracellular fluorescence intensity after transfecting the 5'-FITC-labelled ASODN (FASODN) and cell cycles were determined by flow cytometry (FCM). Inverse microscope was used to observe the modality of A549 cell transfected by NPs for ASODN. The protein expression of hTERT was measured by immunocytochemistry.

Results: The cytotoxicity increased evidently with the increasing concentration of NPs over 2.5 g x L(-1). The intracellular fluorescence in FASODN-NP group was obviously stronger than that in FASODN group (NPs free) after transfection for 24 h (P < 0.01). The inhibitory rate for cell modality change and proliferation after the treatment with ASODN-NP at 72 h reached peak , 62.4% , 44.6% and 36.4% for ASODN1-NP group, ASODN2-NP group and ASODN3-NP group, respectively; The cell cycle in ASODN-NP group varied observably compared with control group and sense oligodeoxynucleotide-nanoparticle (SODN-NP) group and the cell cycle was blocked in G1 phase, the cell number in S phase decreased obviously (P < 0.01); The hTERT protein expression of ASODN-NP group reduced clearly.

Conclusion: ASODN-NP of hTERT can inhibit the proliferation of A549 cells effectively and cause the change of cell cycle, restraint of protein expression of hTERT and cell viability.