Skip to main content
Fig. 1 | BMC Biology

Fig. 1

From: Enhancing circadian clock function in cancer cells inhibits tumor growth

Fig. 1

Induction of rhythmic clock gene and cell cycle gene expression in B16 cells. a Averaged Bmal1-Luc (black line) or Per2-Luc (grey line) bioluminescence after dexamethasone (DEX) treatment of B16 cells. b Per2-Luc bioluminescence of single B16 cells (black: one circadian peak, grey: two circadian peaks, dashed grey: more than two circadian peaks) and their average (thick grey line) after DEX treatment (n = 38). c Representative example of averaged Per2-Luc bioluminescence of B16 cells after forskolin (FSK) treatment. d Representative examples of averaged Bmal1-Luc bioluminescence of B16 cells after heat shock treatment (43 °C for 30 min, black line) and untreated controls (grey line). e Clock gene expression in B16 cells 8–28 h after serum shock (n = 19–23, 3–4 wells/time point; cosine-wave regression, F-test: p < 0.001). f–j Clock gene expression in cultured B16 cells 24–44 h after DEX treatment (black line). The control is shown in grey. Significant rhythms are illustrated with fitted cosine curves, otherwise data are connected by straight lines between data points, indicating no significant circadian rhythms (cosine-wave regression, F-test: control: all genes p > 0.05, DEX: Per1 and Cry1: p < 0.05, n = 18, 3 wells/time point; Per2 and Bmal1: p < 0.0001, n = 35–36, 5–6 wells/time point; Nr1d1: p < 0.001, n = 32–36, 5–6 wells/time point). k–p Expression of six cell cycle genes in B16 cells 24–44 h after DEX treatment. Significant rhythms are illustrated with fitted cosine curves, otherwise data are connected by straight lines between data points, indicating no significant circadian rhythms (n = 36, 6 wells/time point, multi-harmonic cosine-wave regression, F-test: control: p > 0.05, DEX: p21 and c-Myc: p < 0.05; Wee1 and Cyclin E: p < 0.01; Cdk1 and Cdk2: p < 0.001). Data are represented as mean ± standard error of the mean. For details of statistics, see Additional file 1

Back to article page