Efficient translocation and apoptosis induction by adenovirus encoded VP22-p53 fusion protein in human tumor cells in vitro.

BACKGROUND

p53 mutations are one of the most frequent genetic alterations in cancer. Various mechanisms of delivering p53 protein into tumor cells, such as plasmids, retroviruses and adenoviruses, have been widely used in experimental studies. Although these methods are relatively successful, the transduction rate into surrounding cells is still a limiting factor. Recent studies have shown that fusing VP22 (important for intercellular transport) to p53 and delivering this protein to cells in the form of an adenovirus is a very efficient method of getting p53 into cells.

RESULTS

In the present study, the effect of adenovirus encoded VP22-p53 fusion protein on p53 negative human cancer cells (LNCaP, SK-OV-3, OVCAR-3, DU 145) was investigated. A functional VP22-p53 fusion protein was produced as verified by immunofluorescence and analysis of p21 expression. Induction of p21 expression (target gene for p53) confirmed p53 was functional and immunofluorescence staining using p53 antiserum demonstrated the intercellular trafficking ability of the VP22 portion of the fusion protein.

CONCLUSION

In conclusion, VP22-p53 showed efficient translocation into tumor cells, inhibition of tumor cell proliferation and induction of apoptosis. These characteristics make the fusion protein an attractive method for introducing p53 into human cells as well as a potential candidate for gene therapy.