Melatonin Suppresses the Expression of 45S Preribosomal RNA and Upstream Binding Factor and Enhances the Antitumor Activity of Puromycin in MDA-MB-231 Breast Cancer Cells

Figure 5

Combined effect of melatonin and puromycin on the viability and 45S pre-rRNA in MDA-MB-231 cells. (a) Effect of melatonin and/or puromycin on the viability of MDA-MB-231 cells. MDA-MB-231 cells were seeded at a density of 2×10⁴ cells per well on 96-well microplates and treated with melatonin (3 mM) and/or puromycin (1 𝜇m/mL) for 24 hr. Cell viability was assessed by MTT assay. Data were presented as means ± S.D. ## or ^∗∗𝑃<0.01 versus untreated control, ^$$$𝑃<0.001 versus melatonin treated group. (b) Effect of melatonin and/or puromycin on 45S pre-rRNA. The mRNA expression of 45S pre-rRNA was determined by RT-qPCR. GAPDH was used to normalize the expression of pre-rRNA. Data were presented as means ± S.D. ^∗𝑃<0.05 versus untreated control, ^##𝑃<0.01 versus puromycin treated group.

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