Dose-dependent sensitizing effect of 5-ALA on laser-irradiation and DCA mediated effects on cell viability.

MCF-7 cells were cultured in 96-well plates as above in Fig 3 and then treated with 5-ALA (A, 0.5 mM; B, 1.0 mM; C, 2.0 mM) for 4 h followed by indicated doses of laser-irradiation. Cells were then treated with 10 mM DCA. Controls with 5-ALA and DCA alone and in combination without laser irradiation or with any treatment were also included. Cell viability was determined by MTT assay as described in “Materials and Methods” section. Data shown are mean values ± SE from three independent experiments, each performed in triplicate. Asterisk shows values significantly different from control. *P ≤ 0.01.