Abstract:
Objective This work aimed to investigate the therapeutic efficacy of methylene blue (MB) -mediated photodynamic therapy (PDT) with adriamycin (ADM) on 4T1 mouse mammary carcinoma cells in vitro and in vitro, thereby providing a theoretical basis for clinical applications.
Methods The experimental study was divided into four groups, namely, control (Group One), ADM (Group Two), PDT (Group Three), and therapeutic alliance or PDT+ADM (Group Four).Methyl thiazolyl tetrazolium assay was employed to determine the effects of the combined therapy on the proliferation of breast cancer cells.Cell apoptosis and necrosis were measured by flow cytometry with Annexin V-FITC/PI double staining.Rhodamine123 was used to test the change in the mitochondrial membrane potential (MMP) of the 4T1 cells.A 4T1-bearing BALB/c mice model was established, and the tumor volume was measured to draw the growth curve.
Results In Groups Three and Four, cell survival rate gradually decreased as the concentration of the photosensitizer increased.A low death rate was exhibited by Group Two, whereas early and late apoptosis were observed in Group Three and late apoptosis and necrosis were found in Group Four.The results of the MMP detection showed that Groups One, Three, and Four had significant changes (P < 0.05), with the highest MMP decrease in Group Four (P < 0.05).The in vivo experiments demonstrated that PDT significantly inhibited the growth of 4T1-xenografted tumor and that the inhibitory action can be further enhanced with ADM.
Conclusions MB-mediated PDT, which is strengthened by the combination of PDT and ADM, has a significant lethal effect on 4T1 cells in vitro and in vitro.The lethal effect of PDT on cancer cells is shown in the apoptosis and can be attributed to the decrease in MMP.