Head and neck squamous cell carcinoma is highly sensitive to vinorelbine in Vitro
Erjala, K.; Pulkkinen, J.; Kulmala, J.; Alanen, K.; Grenman, R.
Anticancer Research 22(6a): 3135-3142
2002
ISSN/ISBN: 0250-7005 PMID: 12530056 Document Number: 546430
The vinorelbine sensitivity of eight recently established head and neck squamous cell carcinoma (SCC) cell lines was tested using the 96-well plate clonogenic assay. The chemosensitivity of these head and neck SCC cell lines to vinorelbine expressed as IC50, corresponding to the drug concentration causing 50% inhibition in clonogenic survival, varied between 0.6 and 1.0 nM. The dose-dependent growth inhibition caused by vinorelbine was measured in three of these cell lines. A clear growth inhibition was observed at a concentration of 3 nM. The same cell lines were studied with flow cytometry. When exposed to 3 nM and 5 nM vinorelbine, an accumulation of the cells in the G2/M-phase was observed in all cultures after 12 hours. The morphological changes induced by 3 nM and 5 nM vinorelbine to the UT-SCC-33 cell line were analysed with time-lapse video microscopy. In the cultures treated with 5 nM vinorelbine, the cells stayed mitotically arrested for 2-32 hours and thereafter died morphologically by apoptosis. These results indicate that, in vitro, the head and neck SCC is consistently sensitive to vinorelbine, which blocks the cell cycle in G2/M, the most radiosensitive phase. These encouraging results suggest that vinorelbine may potentially be used in conjunction with radiotherapy in the treatment of head and neck SCC.