Growth suppression of human laryngeal squamous cell carcinoma by adenoviral-mediated interleukin-12.

This study explored the inhibitory role of the adenoviral-mediated-interleukin (IL)-12 (Ad.mIL-12) gene in the growth of laryngeal squamous cell carcinoma (LSCC). Human epithelial type 2 (Hep-2) cells were transfected with Ad.mIL-12, and IL-12 gene expression of the cells was evaluated. The proliferation and apoptosis of Hep-2 cells in vitro were detected by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and flow cytometry. Experimental tumours in mice were injected intratumourally with the same recombinant adenoviruses and inhibition of tumour growth observed. Apoptosis in Hep-2 xenotransplants was detected using TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labelling) assay and transmission electron microscopy. The expression of IL-12 in Ad.mIL-12 transfected Hep-2 cells was significantly increased. In vitro, Ad.mIL-12 decreased the viability of and increased apoptosis in Hep-2 cells. Increased apoptosis was also seen in vivo. The mean weight and volume of tumours in Ad.mIL-12 treated mice were significantly lower than in the control group. It is concluded that Ad.mIL-12 can suppress LSCC growth and induce apoptosis.