Hydroxyapatite nanopartides mediated human telomerase reverse transcriptase RNA interference of A549 human lung cancer cells in vitro / 中华胸心血管外科杂志

ABSTRACT

Objective To investigate the effect of hydroxyapatite nanoparticles (nHAP) mediated human telomerase re-verse transcriptase (hTERT) RNA interference of A549 human lung cancer cells in vitro. Methods The nHAP were synthe-sized by the homogeneous precipitation method. The structure of the nanoparticles was observed under transmission electron mi-croscope. The nHAP were prepared using nltrasonication and Na_2CO_3 and modified with poly-L-lysine (PLL) at pH 7. 4. The transfection of pGenesil-hTERT into A549 was divided into four groups as follows nHAP-PLL group mediated by hydroxyapatite nanoparticles modified with poly-L-lysine ( nHAP-PLL), liposome group mediated by Lipefectamine, nHAP group mediated by hydroxyapatite nanoparticles and control group. The growth ability of cells was assayed with methyl thiazolyl tetrazolium meth-od. The expression level of hTERT protein was examined by Western blotting. Flow cytometry was used to detect the apeptosis ratio of A549 cells line. Results Under transmission electron microscope, the synthesized product presented needle-like and well dispersed particles with evenly distributed sizes of (15-20) nm × (60-80) nm. The proliferation of A549 cells of nHAP-PLL group, liposome group and nHAP group were obviously inhibited as compared with the control group (P < 0.05 ).The inhibition rate of nHAP-PLL group was more than the other groups. There was a significant difference inhibition rate be-tween the nHAP-PLL group compared with the liposome group and nHAP group (P <0.05 ). The level of hTERT protein hada similar varietal tendency with the result of proliferation of each group. Flow cytometry showed the apoptasis ratio of nHAP-PLL group, liposome group, nHAP group and control group was (28.1±1.4)%, (19.2±1.3)%, (10.9±1.2)% and (0.3±0.2 ) %, respectively. There was a significant difference in apoptosis ratio between the nHAP-PLL group, liposome group and nHAP group compared with control group( P < 0.05 ). Conclusion A549 human lung cancer cells overexpreas hTERT and this may be a target for inhibiting proliferation of A549. Hydroxyapatite nanoparticles can induce apeptosis of ASA9 cells in vitro. Hydroxyapatite nanoparticles modified with poly-L-lysine can effectively combine and protect DNA and mediate gene transfection to A549, it can mediate human telomerase reverse transcriptase RNA interference of A549 cells and inhibit the pro-liferation of ,4549 in vitro.