UVA Irradiation Enhances Brusatol-Mediated Inhibition of Melanoma Growth by Downregulation of the Nrf2-Mediated Antioxidant Response

Figure 5

Cotreatment causes reduction of melanoma cell-derived tumors in vivo. (a and b) A375 cells were treated with UVA and BR for 7 days. At days 2, 4, and 6, UVA and BR treatment was repeated. After 7 days, colony formation was examined by staining the resulting colonies with crystal violet. Colonies with more than 50 cells were counted (). (c) A375 cells (3.0 × 10⁶) were injected subcutaneously into the right flank of 4-week-old male nude mice ( for each group). When tumor size reached 30~50 mm³, intraperitoneal injections of BR (2 mg/kg) or irradiation with UVA (75 kJ/m²) or with both were administered every other day for five times. (d) Xenograft tumor sizes were measured after mice bearing tumors were treated with either vehicle (control), UVA alone, BR (2 mg/kg), or with a combination of UVA and BR for 10 days (). All data are shown as the mean ± SD; and . All values are based on the analysis of control tumors versus treated ones.

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