The aim of this study was to investigate the potential role of PHRF1 in lung tumorigenesis. Western blot analysis was used to detect the expression of proteins. Quantitative reverse transcriptase polymerase chain reaction, immunohistochemistry, soft agar assay and tumor formation assay in nude mice were applied. Cell cycle distribution was analyzed by flow cytometry. The lower level of PHRF1 mRNA was observed in human lung cancer tissues than that in paracancerous tissues. The decreased expression of PHRF1 protein was observed in H1299 and H1650 cell lines than that in 16HBE and BEAS-2B cell lines. The decreased expression of PHRF1 protein was observed in malignant 16HBE cells compared to control cells. The reduced expression of PHRF1 protein was observed in mice lung tissues treated with BaP than that in control group. Overexpression of PHRF1 inhibited H1299 cell proliferation, colony formation in vitro and growth of tumor xenograft in vivo, and arrested cell cycle in G1 phase. The decreased expression of TGIF and c-Myc proteins and the increased expression of p21 protein were observed in H1299-PHRF1 cells compared with H1299-pvoid cells. In conclusion, our findings suggest that overexpression of PHRF1 attenuated the proliferation and tumorigenicity of non-small cell lung cancer cell line of H1299.
Keywords: H1299 cell; PHRF1; cell cycle; lung cancer; tumorigenicity.