Chlorin E6 Photodynamic Therapy Research Articles

Chlorin E6-Curcumin-Mediated Photodynamic Therapy Promotes an Anti-Photoaging Effect in UVB-Irradiated Fibroblasts.

Skin photoaging due to ultraviolet B (UVB) exposure generates reactive oxygen species (ROS) that increase matrix metalloproteinase (MMP). Chlorin e6-photodynamic therapy (Ce6-PDT), in addition to being the first-line treatment for malignancies, has been shown to lessen skin photoaging, while curcumin is well known for reducing the deleterious effects of ROS. In the current study, PDT with three novel Ce6-curcumin derivatives, a combination of Ce6 and curcumin with various linkers, including propane-1,3-diamine for Ce6-propane-curcumin; hexane-1,6-diamine for Ce6-hexane-curcumin; and 3,3'-((oxybis(ethane-2,1-diyl))bis(oxy))bis(propan-1-amine) for Ce6-dipolyethylene glycol (diPEG)-curcumin, were studied for regulation of UVB-induced photoaging on human skin fibroblast (Hs68) and mouse embryonic fibroblast (BALB/c 3T3) cells. We assessed the antiphotoaging effects of Ce6-curcumin derivatives on cell viability, antioxidant activity, the mechanism of matrix metalloproteinase-1 and 2 (MMP-2) expression, and collagen synthesis in UVB-irradiated in vitro models. All three Ce6-curcumin derivatives were found to be non-phototoxic in the neutral red uptake phototoxicity test. We found that Ce6-hexane-curcumin-PDT and Ce6-propane-curcumin-associated PDT exhibited less cytotoxicity in Hs68 and BALB/c 3T3 fibroblast cell lines compared to Ce6-diPEG-curcumin-PDT. Ce6-diPEG-curcumin and Ce6-propane-curcumin-associated PDT showed superior antioxidant activity in Hs68 cell lines. Further, in UVB-irradiated in vitro models, the Ce6-diPEG-curcumin-PDT greatly attenuated the expression levels of MMP-1 and MMP-2 by blocking mitogen-activated protein kinases (MAPKs), activator protein 1 (AP-1), and tumor necrosis factor-α (NF-κB) signaling. Moreover, Ce6-diPEG-curcumin effectively inhibited inflammatory molecules, such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, while accelerating collagen synthesis. These results demonstrate that Ce6-diPEG-curcumin may be a potential therapy for treating skin photoaging.

The role of autophagy in the treatment of colon cancer by chlorin e6 photodynamic therapy combined with oxaliplatin

BackgroundPhotodynamic therapy is a tumour treatment method. Its mechanism mainly induces apoptosis, autophagy, and other ways to cause cell death. Therefore, this study aims to evaluate the therapeutic effect of chlorine e6 photodynamic therapy (Ce6-PDT) combined with oxaliplatin (L-OHP) in colon cancer and to investigate the role of autophagy in L-OHP treatment and Ce6-PDT combined with L-OHP in colon cancer. MethodsCCK-8 assay, Scratch wound healing assay, and Western Blot (WB) were used to identify drug-resistant colon cancer cell line SW620/L-OHP. Annexin V/FITC assay, laser confocal double immunofluorescence staining method and WB were employed to investigate the apoptosis and autophagy changes in Ce6-PDT combined with L-OHP. ResultsDrug resistance cells SW620/L-OHP were developed under the continuous multi-generation of L-OHP treatment, and the expression of ATP-binding cassette subfamily B member 1 (ABCB1) and ATG5 proteins were increased. The results of immunofluorescence showed that LC3B accumulated in SW620 cells and SW620/L-OHP cells under the treatment of L-OHP. The WB results indicated that LC3B and ATG5 protein expression was increasing in SW620 cells and SW620/L-OHP cells. Inhibition of L-OHP-induced autophagy reduces SW620 cells and SW620/L-OHP cells’ viability while increasing apoptosis and the Pro Caspase-3 protein expression. The combination of Ce6-PDT and L-OHP decreased the cell viability, the cell migration ability, the Bcl-2 protein expression, and increased the apoptosis rate, Pro Caspase-3 protein expression in SW620 cells. ConclusionsL-OHP can cause SW620 cells drug resistance. Autophagy plays a protective role in the L-OHP treatment of SW620 cells and SW620/L-OHP cells, and inhibition of autophagy can increase the efficacy of L-OHP. Ce6-PDT combined with L-OHP can further improve the tumor's therapeutic effect, and autophagy inhibition can improve the efficacy of combined therapy.

Chlorin E6-photodynamic therapy basal cell carcinoma

Purpose of the study. Evaluation of the therapeutic efficacy of chlorin E6-photodynamic therapy (PDT) with photosensitizers (PS) photoditazine, photolone and photoran in patients suffering basal cell skin carcinoma.Materials and methods. The efficacy of chlorin E6-PDT was studied in 532 patients with basal cell skin cancer (BCC) aged 28 to 93 years. PhS Photoditazine was used in 72 (13,5 %) patients at a dose of 0.5-1.0 mg/kg, PhS Photolon - in 281 (52,8 %) patients at a dose of 1.1-1.6 mg/kg and PhS Photoran - in 179 (33,6 %) people at a dose of 1.1-1.6 mg/kg.Sessions of local irradiation of tumor foci were performed on a laser device "Latus-2" (662 nm) with a power density of 200-500 mW/cm2, light energy was applied to the tumors at a dose of 100-300-600 J/cm2.Results. During the follow-up period from 6 months to 5 years, 16.2 % of cases of relapse were diagnosed in the study group. When analyzing the results, it was found that the percentage of relapses was minimal when using all PhS in patients who underwent PDT for the first time established BCC of the initial stages (neoplasms up to 2.0 cm) and amounted to 2.2 % (4 patients out of 183), and with a prevalence of the process of more than 2.0 cm and up to 4.0 cm, 9.5 % (10 patients out of 105) of relapses were found. In the results of treatment of recurrent skin malignancies with PDT using derivatives of chloride E6, depending on the prevalence of the process, a similar trend was observed: with the size of tumor foci up to 2.0 cm, the percentage of repeated relapses was less and amounted to 17.1 % (18 patients out of 105) than in the treatment of neoplasms more than 2.0 cm and up to 4.0 cm (28.8 % of relapses - 21 patients out of 73).Conclusions. Chlorin E6-PDT makes it possible to effectively treat primary and recurrent BCC in an independent variant, and the results of treatment depend on a number of factors, including the prevalence of the disease and the presence or absence of previous treatment.

Inhibition of autophagy enhances apoptosis induced by Ce6-photodynamic therapy in human colon cancer cells

ObjectiveTo evaluate the therapeutic effect of Chlorin e6 photodynamic therapy (Ce6-PDT) in human colorectal cancer cells and investigate the role of autophagy in Ce6-PDT. MethodsSW480 cells underwent Ce6-PDT with and without pretreatment with the autophagy inhibitor 3-methyladenine (3MA). Cell viability was assessed using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was evaluated using an Annexin V assay, using a rhodamine 123 (RH123) assay to evaluate mitochondrial membrane potential (MMP), and by measuring Caspase-3 and Bcl-2 protein expression using western blotting. Autophagy was evaluated by directly visualizing acridine orange-stained acidic vesicular organelles (AVOs) using fluorescent microscopy and by measuring LC3Ⅰ/Ⅱand Atg5 expression using western blotting. ResultsCe6-PDT decreased SW480 viability in a dose-dependent manner. Ce6-PDT induced apoptosis in SW480 cells via the mitochondrial apoptosis pathway as indicated by decreased mitochondrial membrane potential, increased Annexin V staining, and increased Caspase-3 expression. Ce6-PDT was also shown to induce autophagy as demonstrated by increased acridine-orange stained AVOs as well as increased expression of the autophagy-associated proteins Atg5. Inhibition of autophagy with 3MA potentiated SW480 cell response to Ce6-PDT and increased the rate of apoptosis in the treated cells. ConclusionsCe6-PDT induces autophagy and apoptosis of SW480 cells in a dose-dependent manner. Inhibition of autophagy increases the apoptosis induced by Ce6-PDT. Modulation of autophagy may be a potential therapeutic target for colon cancer cells treated with Ce6-PDT.

Downregulation of Rac1/PAK1/LIMK1/cofilin signaling pathway in colon cancer SW620 cells treated with Chlorin e6 photodynamic therapy.

Colorectal cancer is one of the most common gastrointestinal malignancies. Photodynamic therapy (PDT) is a novel and non-invasive treatment for tumors as PDT features small trauma, good applicability, andaccurate targeting. PDT may also be a potential treatment for colon cancer as itmay may induce suppressive effects on metastatic potential.. However, the molecular mechanism of the Chlorin e6 Photodynamic therapy (Ce6-PDT) inhibiting the migration of human colon cancer SW620 cells remains unclear. Scratch wound healing assay, scanning electron microscope, MTT, immunofluorescence and laser confocal technique were used to investigate the suppressive effects of Ce6-PDT on the SW620 cells migration, pseudopodia, viability and the actin cytoskeleton. The effect of Ce6-PDT on actin-Filaments and signaling molecules of the Rac1/PAK1/LIMK1/cofilin signaling pathway in SW620 cells were examined by western blot analysis. RNA interference (RNAi) technology was used to establish siRNA-Rac1/SW620 cells. The combined effects of Ce6-PDT and RNAi on colon cancer SW620 cells was investigated by the same technology and methods mentioned above to clarify the signal transduction effect of Rac1/PAK1/LIMK1/cofilin signaling pathway in Ce6-PDT caused inhibition of SW620 cell migration. The healing and migration rate of the SW620 cells was significantly reduced and the cell pseudopodia were reduced or disappeared by Ce6-PDT. The Immunofluorescence and western blot analysis results showed that Ce6-PDT destroy microfilament's original structure and significantly downregulated F-actin protein expression. The Rac1/PAK1/LIMK1/cofilin signaling pathway was downregulated by Ce6-PDT. Furthermore, the RNAi significantly strengthened the effect of Ce6-PDT on colon cancer SW620 cells migration. Actin cytoskeleton and protrusions of SW620 cells correlate with its migration ability. Ce6-PDT suppresses SW620 cells migration by downregulating the Rac1/PAK1/LIMK1/cofilin signaling pathway, and its suppressive effect was enhanced by knocking down Rac1 gene expression.

The effect of antiamoebic agents and Ce6‐PDT on acanthamoeba castellani trophozoites and cysts, in vitro

AbstractPurposeTo analyze the concentration dependent effect of diamidines (hexamidine‐diisethionat (HD), propamidin‐isethionate (PD), dibromopropamidine‐diisethionat (DD)); biguanides (polyhexamethylen biguanid (PHMB), chlorhexidine (CH)); natamycin (NM); miltefosine (MF); povidone iodine (PVPI) and chlorin e6 photodynamic therapy (PDT) on Acanthamoeba castellani trophozoites and cysts, in vitro.MethodsAcanthamoeba castellani strain was cultured in 712 peptone‐yeast extract‐glucose (PYG) medium. Thereafter, trophozoites or cysts were cultured in 0.25–0.1% HD, PD or DD, or 0.005–0.02% PHMB, CH or NM or 0.001625–0.0065 MF or 0.25–1% PVPI containing PYG medium for 2 h or underwent Chlorin e6‐PDT. Then, the percentage of dead trophozoites was determined by CytoTox 96® Non‐Radioactive Cytotoxicity assay and trypan blue staining and those of cysts using trypan blue staining. Treated trophozoites and cysts were also inoculated to non‐nutrient agar Eshericia coli plates and were observed for 5 weeks.ResultsAll concentrations of different antiamoebic agents had a significant cytotoxic effect on AK trophozoites and cysts (p < 0.05), except 0.02% PHMB and CH, using trypan blue assay for trophozoites, and Ce6‐PDT for cysts. Observing the agar plates, HD, PD, PHMB, CH, NM and PVPI led to morphological changes of acanthamoeba trophozoites, which could not form cysts within 5 weeks. DD and MF treated cysts could excyst and later encyst again.ConclusionsConservative treatment using different antiamoebic agents or Ce6‐PDT can not eradicate all Acanthamoeba castellani trophozoites and cysts. In vitro analyzis of treatment efficacy of different antiamoebic agents may alow a more specific treatment in acanthamoeba keratitis.

Enhanced cytotoxicity and apoptosis through inhibiting autophagy in metastatic potential colon cancer SW620 cells treated with Chlorin e6 photodynamic therapy

Photodynamic therapy (PDT) is a novel and non-invasive treatment that induces apoptosis and autophagy. Autophagy could play a pro-survival role, thus inhibiting autophagic activity might be a promising method to enhance the effectiveness of PDT for tumors. In the present study, photosensitizer Chlorin e6 (Ce6) was found to mainly locate in endoplasmic reticulum, and to a lesser extent in mitochondria and lysosome. Chlorin e6 photodynamic therapy (Ce6-PDT) could kill human colon cancer SW620 cells by inducing apoptotic cell death, and autophagy also induced by Ce6-PDT in colon cancer cells. More importantly, autophagy played a pro-survival role. Its inhibition enhanced Ce6-PDT-associated apoptotic cell death because cells pretreated with the typical autophagy inhibitor 3-methyladenine exhibited higher cytotoxicity and apoptotic cell death.

Effective treatment of chemoresistant breast cancer in vitro and in vivo by a factor VII-targeted photodynamic therapy

Background:The purpose of this study was to test a novel, dual tumour vascular endothelial cell (VEC)- and tumour cell-targeting factor VII-targeted Sn(IV) chlorin e6 photodynamic therapy (fVII-tPDT) by targeting a receptor tissue factor (TF) as an alternative treatment for chemoresistant breast cancer using a multidrug resistant (MDR) breast cancer line MCF-7/MDR.Methods:The TF expression by the MCF-7/MDR breast cancer cells and tumour VECs in MCF-7/MDR tumours from mice was determined separately by flow cytometry and immunohistochemistry using anti-human or anti-murine TF antibodies. The efficacy of fVII-tPDT was tested in vitro and in vivo and was compared with non-targeted PDT for treatment of chemoresistant breast cancer. The in vitro efficacy was determined by a non-clonogenic assay using crystal violet staining for monolayers, and apoptosis and necrosis were assayed to elucidate the underlying mechanisms. The in vivo efficacy of fVII-tPDT was determined in a nude mouse model of subcutaneous MCF-7/MDR tumour xenograft by measuring tumour volume.Results:To our knowledge, this is the first presentation showing that TF was expressed on tumour VECs in chemoresistant breast tumours from mice. The in vitro efficacy of fVII-tPDT was 12-fold stronger than that of ntPDT for MCF-7/MDR cancer cells, and the mechanism of action involved induction of apoptosis and necrosis. Moreover, fVII-tPDT was effective and safe for the treatment of chemoresistant breast tumours in the nude mouse model.Conclusions:We conclude that fVII-tPDT is effective and safe for the treatment of chemoresistant breast cancer, presumably by simultaneously targeting both the tumour neovasculature and chemoresistant cancer cells. Thus, this dual-targeting fVII-tPDT could also have therapeutic potential for the treatment of other chemoresistant cancers.