Table 1.
Custom designed protein arrays kit, which consist of 20 different cytokines/factors.
Figure 1.
Inhibitory effect of melatonin on viability of the MDA-MB-231 cell line.
The MDA-MB-231 cells were treated with five concentrations of melatonin for 24 h and cell viability was measured by MTT assay. Data are shown as mean ± S.D. *p<0.05, 1 mM of melatonin vs. Control; #p<0.05, 1 mM of melatonin vs other melatonin's concentrations.
Figure 2.
Antitumor effects of melatonin on mammary tumor growth.
Melatonin reduced the tumor growth in breast cancer nude mice. Each point in the curves represents the mean ± SD (control n = 8; melatonin n = 5). The melatonin inhibited tumor growth, *p<0.05 vs Control. # Significant increase in tumor volume on control group at 14 and 21 after tumor implantation and initiation of treatment with vehicle (p<0.05). Detail: Representative samples of mammary tumors developed by MDA-MB-231 cells implantation on the right flank of mice. A, B. Melatonin treated mammary tumors, B. Mammary tumor which regressed with melatonin treatment. C, D. Vehicle treated mammary tumors.
Figure 3.
SPECT analysis of in vivo accumulation of Tc-99m-HYNIC-VEGF-c.
VEGF-c (which targets both VEGFR2 and VEGFR3) was tagged with HYNIC chelators and then labeled with Tc-99m and injected intravenously in melatonin and vehicle treated mice. One hour after injection, SPECT images were obtained using dedicated animal scanner. Vehicle treated mice showed increased accumulation of Tc-99m-HYNIC-VEGF-c in the mammary tumor (A, Intersection of lines indicate the tumor, with a volume of 865.69 mm3 at the 21th day) compared to that of melatonin treated mammary tumors (B, Intersection of lines indicate the tumor, with a volume of 130.69 mm3 at the 21th day) C. Semi-quantitative analysis of total radioactivity normalized to contralateral muscles showing the intensity of radioactivity in the vehicle and melatonin treated animals.
Figure 4.
Comparison between proteins expression in mammary tumor in animals treated with melatonin or vehicle.
White column = vehicle treatment; Black column = melatonin treatment. Data are shown as mean ± S.D. *p<0.05, vs. Control.
Figure 5.
Immunohistochemistry staining with VEGFR2 (arrows) in vehicle treated and melatonin treated tumors.
Images were taken with 40× magnification. A significant decrease was observed at the tumor in melatonin treated tumors compared to vehicle treated tumors (*p<0.05). Error bars: ± standard error.
Figure 6.
Immunohistochemistry staining with VEGFR3 (arrows) in vehicle treated and melatonin treated tumors.
Images were taken with 40× magnification. Melatonin do not decreased significantly the expression of VEGFR3 (p>0.05). Error bars: ± standard error.
Figure 7.
Immunohistochemistry staining with vWF in vehicle treated and melatonin treated tumors.
Images were taken with 40× magnification. Quantitative estimation of micro-vessel density (MVD) by counting positive vessels (arrows) revealed a decrease in MVD after melatonin treatment compared to the vehicle treated tumor (*p<0.05). Error bars: ± standard error.
Figure 8.
Immunohistochemistry staining with Ki-67 in vehicle treated and melatonin treated tumors.
Images were taken with 40× magnification. There was a decreased cell proliferation in tumors treated with melatonin (*p<0.05). Error bars: ± standard error.