Objectives: This project aims to assess the effects of rhBMP-7 upon HNSCC cells in vitro.
Methods: Three well characterised HNSCC cell lines (BICR56, TCR146 and T4) and normal primary and immortalised keratinocytes (OKF6) were grown in Keratinocyte medium and the effects of rhBMP7 on cell growth, colony formation efficiency, cell metabolism, cell viability, senescence, invasive capacity and Apoptosis determined.
Results: The growth rate, metabolic rate and colony forming potential of all three HNSCC and immortalised keratinocytes were statistically significantly reduced and the cell doubling time increased by rhBMP-7 in a dose dependent fashion. There was a statistically significant dose-related increase in LDH release in rhBMP-7–treated cultures. Primary oral keratinocytes appeared to grow normally in the presence of this factor. An effect on HNSCC senescence was only observed at the highest rhBMP-7 concentration. A greater number of apoptotic cells were detected in the rhBMP-7-treated HNSCC indicating that programmed cell death was one mechanism responsible for reduced cell numbers.
Although, the invasive capability of HNSCC in the presence or absence of rHBMP-7 appeared to be similar, the variability in the assay was too great to be certain.
Conclusion: rhHBMP-7 inhibits the growth and colony forming potential of a number of HNSCC. Therefore rhBMP-7 it does not appear to have pro-tumourigenic properties with regard to HNSSC. Further studies of cell invasion are required to eliminate the possibility that this behaviour is stimulated.