Fig. 3.

The effects of dexamethasone and tumor PDT on liver Hsp70 gene expression. Tumor-free C57BL/6 mice were i.p. injected either with dexamethasone (40 μk/kg) or control solution. Alternatively, mice with LLC tumors were treated with PDT as described in Fig. 2 and some were given metyrapone (100 mg/kg, i.p.) 15 min before the onset of PDT light exposure. The mice were sacrificed at 4 h post treatment and their livers collected for quantitative RT-PCR-based analysis of Hsp70 gene expression. The results are presented as the GAPDH-normalized Hsp70 gene expression relative to that in the liver of tumor-free controls or untreated LLC tumor-bearing controls. N = 4, bars are SD; *p < 0.05, statistically significant difference compared to untreated controls; **p < 0.05, statistically significant difference compared to the PDT-only group