Bone invasive properties of oral squamous cell carcinoma and its interactions with alveolar bone cells: an in vitro study.

BACKGROUND: Co-culture of cancer cells with alveolar bone cells could modulate bone invasion and destructions. However, the mechanisms of interaction between oral squamous cell carcinoma (OSCC) and bone cells remain unclear.

OBJECTIVE: The aim of this study is to analyse the direct and indirect effects of OSCC cells in the stimulation of osteolytic activity and bone invasion.

METHOD: Direct co-culture was achieved by culturing OSCC (TCA8113) with a primary alveolar bone cell line. In the indirect co-culture, the supernatant of TCA8113 cells was collected to culture the alveolar bone cells. To assess the bone invasion properties, in vitro assays were performed.

RESULTS: The proliferation of co-cultured cancer cells was significantly (p<0.05) higher in comparison to the monolayer control cells. However, the proliferation rates were not significantly different between direct and indirect co-cultured cells with indirect co-cultured cells proliferated slightly more than the direct co-cultured cells. Invasion and migration capacities of co-cultured OSCC and alveolar bone cells enhanced significantly (p<0.05) when compared to that of control monolayer counterparts. Most importantly, we noted that OSCC cells directly co-cultured with alveolar bone cells stimulated pronounced bone collagen destruction. In addition, stem cells and epithelial-mesenchymal transition markers have shown significant changes in their expression in co-cultured cells.

CONCLUSIONS: In conclusion, the findings of this study highlight the importance of the interaction of alveolar bone cells and OSCC cells in co-culture setting in the pathogenesis of bone invasion. This may help in the development of potential future biotherapies for bone invasion in OSCC.