[Role of siRNA mediated matrix metalloproteinase-2 gene silencing in the inhibition of invasion and growth of laryngeal cancer cells].
OBJECTIVE
To explore the inhibitory effect of matrix metalloproteinase-2 (MMP-2) gene silencing in vitro and in vivo on the invasion and growth of laryngeal cancer cells.


METHODS
siRNA recombinant lentivirus targeting MMP-2 gene was transfected into Hep-2 cells, and MMP-2 protein expression was analyzed consequently by using western-blot. Invasive properties of transfectants were evaluated by Boyden assay. In addition, the lentivirus was intratumorally injected in a model of the grafted nude mouse and the morphological changes of transfectants were examined by transmission electron microscope. Finally, cell proliferation in xenografts was measured by immunolabeling of proliferating cell nuclear antigen (PCNA).


RESULTS
Over 90% of target cancer cells were found to be transfected by MMP-2-RNAi-Lentivirus. Western-blot analysis revealed that none of transfectants expressed MMP-2 protein whereas most untreated cancer cells exhibited positive protein expression. Significant differences were found between the treated and untreated groups regarding the number of transfectants penetrating through an artificial basement in a Boyden chamber (12 +/- 4 vs 35 +/- 6, x +/- s, t = 14.492, P < 0.01), and the average value of weight [(1.186 +/- 0.225) g vs [(2.127 +/- 0.344) g] and volume [(0.974 +/- 0.216) cm3 vs (1.618 +/- 0.272) cm3] of the grafted tumors (t was 7.094 and 5.684, P < 0.01). The overall tumor inhibitive rate was about 44.2%. Transmission electron microscope showed an obviously decreased invasive feature of transfectants. Finally, the percentages of transfectants immunolabeled for PCNA were significantly lower in the treated group (49.588 +/- 6.995) than those (71.434 +/- 7. 043) in control one (t = 9. 573, P < 0.01).


CONCLUSIONS
The invasion, growth and proliferation of laryngeal cancer can be inhibited by siRNA mediated MMP-2 gene silencing. These data strongly suggest that MMP-2 gene silencing by siRNA technology could be a promising approach to cancer therapy.
Liu
Ming
M
Department of Otorhinolaryngology Head and Neck Surgery, The Second Affiliated Hospital, Harbin Medical University, Harbin 150086, China.
Sun
Ya-Nan
YN
Jiao
Hui
H
Tian
Lin-Li
LL
Guo
Yan-Ling
YL
D000818:Animals; D002281:Carcinoma, Basosquamous / Q000235:genetics / Q000473:pathology*; D056945:Hep G2 Cells; D006801:Humans; D007822:Laryngeal Neoplasms / Q000235:genetics / Q000473:pathology*; D016086:Lentivirus / Q000235:genetics; D020778:Matrix Metalloproteinase 2 / Q000235:genetics*; D051379:Mice; D008819:Mice, Nude; D034622:RNA Interference; D014162:Transfection
D020778:Matrix Metalloproteinase 2