Objective   To explore the molecular mechanisms potentially responsible for carcinogensis due to nickel, and to determine whether the translation initiation factor 3 (TIF3) was overex pressed during malignant transformation of human bronchial epithelial cell lines (16HBE) induced by crystalline nickel sulfide (NiS).

  Methods   The abnormal expression of TIF3 mRNA in malignant transformed human bronchial epithelial cells and tumorigenic cells induced by crystalline NiS were detected with both reverse transcription PCR technique and sensitive fluorescent quantitative PCR assay.

  Results   Compared with non-transformed human bronchial epithelial cells, the results of RT-PCR experiments primarily showed that the transformed cells and tumorigenic cells express high levels of TIF3 mRNA, the over expressions of TIF3 mRNA were further observed in these cells, the levels of TIF3 mRNA, expression in the transformed cells and tumorigenic cells were higher 2 times and 4 times respectively as compared with control cells, indicating that expression level of TIF3 gene was related to malignant degree of the cells.

  Conclusion   There was markedly abnormal expression of TIF3 gene during malignant transformation of human bronchial epithelial cell line induced by crystalline NiS, and the TIF3 expression was associated with malignant degree of the cells. That may be the molecular mechanisms potentially responsible for carcinogensis due to nickel.