Effects of LLLT on Malignant Cells: Study in Vitro

摘要

In addition to our previous report on the effects of LLLT on the proliferation of laryngeal carcinoma cells in which it was found that irradiation H.Ep.2 cells with 670nm laser results in increased cell proliferation, it was decided to evaluate the effect of increased doses of laser light. The aim of this study was to assess the effect off 635 and 670 nm laser irradiation of H.Ep.2 cells in vitro using MTT. The cells, obtained from SCC of the larynx, were routinely processed from defrost to the experimental condition. The cultures were kept either at 5 or 10 percent of FBS. Twenty-four hours after transplantation, the cells were irradiated with laser light (5mW diode lasers: 635 and 670nm, beam cross section approx 1mm) at local light doses between 0.04 and 4.8X10~4 Jm~(-2). For 670 nm, significant differences in the proliferation were observed between the two concentrations of FBS (p=0.002) and between irradiated cultures and controls (p=0.000). Although the results were not significant, 635 nm irradiated cells also proliferated more than non-irradiated ones. This occurred under both conditions of nutrition. It is concluded, that irradiation with 670nm laser light applied at doses between 0.04 and 4.810~4 Jm~(-2) could significantly increase proliferation of laryngeal cancer cells.