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BACKGROUND: Enoxolone, derived from licorice, possesses potent anti-inflammatory, and antioxidant properties. However, its effectiveness in alleviating post-laser reactions has not been extensively studied. AIMS: This randomized split-face pilot study aimed to evaluate the effects of enoxolone on skin following laser treatment. PATIENTS/METHODS: Ten healthy subjects underwent non-ablative 1550 nm Er:Glass fractional laser treatment and then randomly applied a moisturizer without enoxolone on one side of the face and a dermo-cosmetic formular containing 2% enoxolone mixed with the same moisturizer on the other side. The erythema index (EI), clinician's erythema assessment (CEA), and pain scores were recorded at 30 min, 60 min, and 24 h posttreatment. RESULTS: The group treated with enoxolone showed significantly lower EI and CEA compared to the control group at 24 h posttreatment. Additionally, pain scores were notably reduced in the enoxolone-treated group 30 min after treatment. CONCLUSIONS: This study suggests that dermo-cosmetic formular containing 2% enoxolone is effective in reducing erythema and pain following laser treatment.
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Eritema , Humanos , Proyectos Piloto , Eritema/etiología , Eritema/prevención & control , Eritema/tratamiento farmacológico , Femenino , Adulto , Dimensión del Dolor , Resultado del Tratamiento , Masculino , Láseres de Estado Sólido/uso terapéutico , Antiinflamatorios/administración & dosificación , Persona de Mediana Edad , Cara , Piel/efectos de la radiación , Piel/efectos de los fármacos , Piel/patología , Voluntarios Sanos , Crema para la Piel/administración & dosificaciónRESUMEN
Recently, particulate matter (PM) has been shown to exacerbate atopic dermatitis (AD) by inducing an inflammatory response. Meanwhile, several studies revealed that exosomes derived from adipose tissue-derived mesenchymal stem cells promote wound healing and alleviate inflammation via their regenerative and immunomodulatory capacities. Our study aimed to investigate the effects of human adipose tissue-derived mesenchymal stem cell-derived (ASC)-exosomes in PM-induced AD. An AD-like triple-cell model was established by treating human keratinocytes, dermal fibroblasts, and mast cells with polyinosinic:polycytidylic acid (Poly I:C) and interleukin 1 alpha (IL-1α). The effects of PM and ASC-exosomes on the expression of pro-inflammatory cytokines and skin barrier proteins were examined using quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence. PM increased pro-inflammatory cytokines (IL-6, IL-1ß, and IL-1α) and decreased the anti-inflammatory cytokine IL-10, while the mRNA expression of skin barrier proteins (loricrin and filaggrin) decreased. However, when the cells were treated with ASC-exosomes, the PM-induced effects on pro-inflammatory cytokines and skin barrier proteins were reversed. Our results confirmed that PM-induced inflammation and skin barrier damage were alleviated by ASC-exosomes in our AD-like triple-cell model. These data suggest that ASC-exosomes can serve as a therapeutic agent for PM-exacerbated AD.
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Dermatitis Atópica , Exosomas , Humanos , Dermatitis Atópica/terapia , Dermatitis Atópica/tratamiento farmacológico , Exosomas/metabolismo , Material Particulado/toxicidad , Material Particulado/metabolismo , Citocinas/metabolismo , Inflamación/metabolismo , Tejido Adiposo/metabolismo , Piel/metabolismoRESUMEN
The response rate to obeticholic acid (OCA), a potential therapeutic agent for non-alcoholic fatty liver disease, is limited. This study demonstrated that upregulation of the alternative bile acid synthesis pathway increases the OCA treatment response rate. The hepatic transcriptome and bile acid metabolite profile analyses revealed that the alternative bile acid synthesis pathway (Cyp7b1 and muricholic acid) in the OCA-responder group were upregulated compared with those in the OCA-non-responder group. Intestinal microbiome analysis also revealed that the abundances of Bacteroidaceae, Parabacteroides, and Bacteroides, which were positively correlated with the alternative bile acid synthesis pathway, were higher in the OCA-responder group than in the non-responder group. Pre-study hepatic mRNA levels of Cyp8b1 (classic pathway) were downregulated in the OCA-responder group. The OCA response rate increased up to 80% in cases with a hepatic Cyp7b1/Cyp8b1 ratio ≥ 5.0. Therefore, the OCA therapeutic response can be evaluated based on the Cyp7b1/Cyp8b1 ratio or the alternative/classic bile acid synthesis pathway activity.
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Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Esteroide 12-alfa-Hidroxilasa , Ácidos y Sales Biliares , BiomarcadoresRESUMEN
BACKGROUND: Dupilumab facial redness (DFR) is a side effect of dupilumab treatment that has only been recently reported. We previously reported on two patients with DFR who were successfully treated with a topical formulation containing human adipose tissue-derived mesenchymal stem cell-derived exosomes (ASCEs). OBJECTIVES: The study aimed to evaluate the efficacy and safety of ASCEs in DFR. PARTICIPANTS AND METHODS: We performed 12-week prospective study at single center. Twenty adult atopic dermatitis patients diagnosed with DFR were enrolled. They were treated with a topical application of the exosome formulation every week for five consecutive weeks. RESULTS: After exosome treatment, both the average investigator global assessment score and clinical erythema assessment scale scores decreased. 19 patients (95%) were satisfied with the treatment. Compared to baseline, erythema index at week 4 were decreased by 31, 27, 13, and 25 units on the forehead, chin, right and left cheek respectively. The analysis of stratum corneum samples revealed the expression of IL-1α and human thymic stromal lymphopoietin was suppressed after exosome treatment, whereas filaggrin and vascular endothelial growth factor expression increased. CONCLUSIONS: This study suggests topical formulation containing ASCEs can alleviate DFR by downregulating local inflammation and restoring skin barrier function.
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Dermatitis Atópica , Exosomas , Adulto , Humanos , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/metabolismo , Exosomas/metabolismo , Estudios Prospectivos , Factor A de Crecimiento Endotelial Vascular , Método Doble Ciego , Eritema , Índice de Severidad de la Enfermedad , Células Madre/metabolismo , Resultado del TratamientoRESUMEN
Hepatocyte nuclear factor 4 alpha (HNF4α) is a key master transcriptional factor for hepatic fat and bile acid metabolic pathways. We aimed to investigate the role of HNF4α in non-alcoholic fatty liver disease (NAFLD). The role of HNF4α was evaluated in free fatty acid-induced lipotoxicity and chenodeoxycholic acid (CDCA)-induced bile acid toxicity. Furthermore, the role of HNF4α was evaluated in a methionine choline deficiency (MCD)-diet-induced NAFLD model. The overexpression of HNF4α reduced intracellular lipid contents and attenuated palmitic acid (PA)-induced lipotoxicity. However, the protective effects of HNF4α were reversed when CDCA was used in a co-treatment with PA. HNF4α knockdown recovered cell death from bile acid toxicity. The inhibition of HNF4α decreased intrahepatic inflammation and the NAFLD activity score in the MCD model. Hepatic HNF4α inhibition can attenuate bile acid toxicity and be more effective as a therapeutic strategy in NAFLD patients; however, it is necessary to study the optimal timing of HNF4α inhibition.
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Recent studies have demonstrated that particulate matter (PM) can induce oxidative stress and inflammatory responses that are related to the development or exacerbation of several inflammatory dermatoses. However, the effect of PM on acne vulgaris has yet to be determined. In this study, we induced acne-like inflammation in HEKn cells with several concentrations of Cutibacterium acnes (C. acnes) and Staphylococcus aureus peptidoglycan (PGN) to investigate whether PM exposure exacerbates acne-like inflammation and elucidate the underlying mechanisms. To confirm whether PM increases the messenger ribonucleic acid (mRNA) and protein levels of proinflammatory cytokines (IL-1α, IL-1ß, IL-6, IL-8, and TNF-α) and cyclooxygenase (COX)-2 expression in C. acnes- or PGN-treated HEKn cells, we used quantitative real-time polymerase chain reactions, enzyme-linked immunosorbent assays, and western blot assays. The results demonstrated that C. acnes, PGN, and PM induced the expression of proinflammatory cytokines in a time- and dose-dependent manner at the mRNA and protein levels, respectively. Moreover, PM further increased the expression of proinflammatory cytokines, COX2, TLR4, and the phosphorylation of NF-κB in C. acnes- and PGN-treated HEKn cells. In conclusion, our results suggest that PM may exacerbate acne symptoms by increasing the inflammatory response.
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Acné Vulgar , FN-kappa B , Acné Vulgar/metabolismo , Citocinas/metabolismo , Humanos , Inflamación/metabolismo , Queratinocitos/metabolismo , FN-kappa B/metabolismo , Material Particulado/metabolismo , Material Particulado/toxicidad , Peptidoglicano/metabolismo , Propionibacterium acnes , ARN Mensajero/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismoRESUMEN
Recently, a novel hyaluronic acid (HA) filler containing the epidermal growth factor (EGF) was developed. The objective of this study was to evaluate the rheological properties, preclinical efficacy and biocompatibility of the EGF-containing HA filler (HA-EGF filler) using a photoaged mouse model. The rheological properties of the new HA-EGF filler were assessed. Twenty-four female hairless mice (SKH1) underwent photoaging induction with 8 weeks of ultraviolet-B irradiation. The mice were randomly divided into four groups and intradermally injected 100 µl of phosphate-buffered saline, HA-EGF filler, HA filler or polynucleotide (PN) into the dorsal region. We examined the effect of fillers on photoaged skin by dermoscopic examination. Furthermore, histological evaluation with immunohistochemical staining was performed to determine the biocompatibility and collagen formation at the 10th week. A real-time quantitative polymerase chain reaction analysis and western blot test assessed the expression of collagen I/III, matrix metalloproteinases (MMPs) and transforming growth factor. The viscosity and elasticity of the HA-EGF filler were lower than those of the HA filler. Histological evaluation revealed no significant differences in the collagen synthesis between the HA-EGF, HA and PN filler groups. No inflammation was observed during the experimental period. The HA-EGF filler induced type I/III collagen production and downregulated the expression of MMP-1, 3 and 9. Our results suggest that the novel HA-EGF filler may be an additional therapeutic option for photoaged skin, which works by inducing collagen synthesis. Based on these preclinical results, further well-controlled clinical studies are required.
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Rellenos Dérmicos , Envejecimiento de la Piel , Femenino , Ratones , Animales , Ácido Hialurónico/farmacología , Rellenos Dérmicos/farmacología , Factor de Crecimiento Epidérmico , Ratones Pelados , Colágeno Tipo IRESUMEN
BACKGROUND/AIMS: We aim to evaluate the effects of auranofin, a known antioxidant, on hepatic steatosis, inflammation, and fibrosis, contributing to non-alcoholic steatohepatitis (NASH) development in vivo and in vitro. METHODS: Transcriptome analysis of LX-2 cells was that expression patterns of genes changed by auranofin, and their related pathways were estimated. We used the gene set enrichment analysis (GSEA) program to determine the pathway involved in overall genetic change. In vitro, LX-2 and HepG2 cells were treated with transforming growth factor (TGF)-ß1 and palmitic acid (PA), respectively, and the antifibrotic and antiadipogenic effect function of auranofin was evaluated. RESULTS: Transcriptome analysis revealed that auranofin decreased the expression of 15 genes, including thrombospondin 1, endothelin 1 (ET-1), fibronectin 1, and LOX. The molecular functions of these genes are involved in collagen binding. GSEA of the overall gene expression pattern revealed that many genes increased in the reactive oxygen species pathway and decreased in the inflammatory response. Auranofin decreased nuclear factor kappa B (NF-κB) and IκBα in TGF-ß1-induced LX-2 cells, thereby reducing ET-1 and fibrosis. Furthermore, increased pNRF2 in PA-induced HepG2 cells led to increased antioxidant marker expression and decreased lipid accumulation. In the bile duct ligation model mice, auranofin reduced the fibrosis area and increased the survival rate. Auranofin reduced liver fibrosis and lipid accumulation in NASH model mice fed on a Western diet. CONCLUSION: Auranofin inhibits lipogenesis and fibrosis formation and is a proposed candidate for NASH treatment.
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Enfermedad del Hígado Graso no Alcohólico , Ratones , Humanos , Animales , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , FN-kappa B/metabolismo , FN-kappa B/farmacología , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/farmacología , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Auranofina/farmacología , Auranofina/uso terapéutico , Auranofina/metabolismo , Inhibidor NF-kappaB alfa/metabolismo , Trombospondina 1/metabolismo , Trombospondina 1/farmacología , Fibronectinas/metabolismo , Fibronectinas/farmacología , Ácido Palmítico/toxicidad , Ácido Palmítico/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Endotelina-1/metabolismo , Endotelina-1/farmacología , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Antioxidantes/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal , Cirrosis Hepática/patología , Factores de Crecimiento Transformadores/metabolismo , Factores de Crecimiento Transformadores/farmacología , Colágeno/metabolismo , Colágeno/farmacología , Hígado/patologíaRESUMEN
Background: Airborne particulate matter (PM), a widespread air contaminant, is a complex mixture of solids and aerosols composed of particles suspended in the air. PM is associated with inflammatory responses and may worsen inflammatory skin diseases. However, the mechanisms through which PM affects atopic dermatitis (AD) remain unclear. Objective: To establish an in vitro model that more accurately mimics AD using human keratinocyte (HaCaT), dermal fibroblast (HDF), and mast cell (HMC-1) and using this model to investigate the mechanism through which PMs affect AD. Methods: An AD-like in vitro model was established by seeding HaCaT, HDF, and HMC-1 cells with recombinant human interleukin (IL)-1α and polyinosinic:polycytidylic acid. We confirmed the effect of PM on the inflammatory cytokine expression of a triple-cell culture model. SRM 1649b Urban Dust, which is mainly composed of polycyclic aromatic hydrocarbons, was used as the reference PM. The effects of PM on the expression levels of proinflammatory cytokines and skin barrier markers were assessed using quantitative real-time polymerase chain reaction and western blotting. Inflammatory cytokine levels were measured using an enzyme-linked immunosorbent assay. Results: Interactions between various skin cell types were evaluated using a co-culture system. PM treatment increased mRNA and protein levels of the inflammatory cytokines IL-6, IL-1α, tumor necrosis factor-α, IL-4, and IL-1ß and decreased the expression of the skin barrier markers filaggrin and loricrin. Conclusion: Our results suggest that an in vitro triple-cell culture model using HaCaT, HDF, and HMC-1 cells may be reliable for obtaining more physiological, functional, and reproducible data on AD and skin barriers.
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BACKGROUND/AIMS: Pancreatic cancer has a very poor prognosis, and early diagnosis is a way to increase the survival rate of patients. The purpose of this study was to develop pancreatic cancer-specific peptides for imaging studies. METHODS: Three pancreatic cancer cell lines, MIA PaCa-2, UACC-462, and BxPC-3, and a control cell line, CCD841, were used. Biopannings were performed on MIA PaCa-2 using a phage display library. After this, the peptides were synthesized and labeled with fluorescein isothiocyanate (FITC). Immunocytochemistry (ICC), enzyme-linked immunosorbent assay (ELISA), and fluorescence- activated cell sorter (FACS) were performed to examine the specific binding. To examine its therapeutic applications, a photosensitizer, chlorin e6 (Ce6), was conjugated on the peptide and photodynamic therapy was performed. Cell survival was investigated using a [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] assay. RESULTS: After three biopannings, the phages were amplified from 1.4×104 to 3.2×105 plaque-forming units. The most strongly binding phage was selected from the ELISA and ICC results. FITC-labeled peptide, M5, in the three pancreatic cancer cell lines showed significantly higher immunofluorescence in the ICC experiments than that of CCD841. The higher binding ability to MIA PaCa-2 cells was confirmed from FACS analysis, which showed a right shift compared to CCD841. M5 bound to Ce6 showed a significantly lower cell survival rate than that of Ce6 alone in photodynamic therapy, which was observed consistently as a change in the tumor size and fluorescence intensity in MIA PaCa-2 cell-implanted animal models. CONCLUSIONS: This study showed that the noble peptide, M5, binds specifically to the pancreatic cancer cell line, MIA PaCa-2. The M5 peptide has potential use in future optical diagnostic and therapeutic purposes.
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Técnicas de Visualización de Superficie Celular/métodos , Péptidos/metabolismo , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Clorofilidas , Fluoresceína-5-Isotiocianato/química , Humanos , Luz , Ratones , Ratones Desnudos , Imagen Óptica , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/tratamiento farmacológico , Péptidos/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/químicaRESUMEN
Targeted drug delivery has been an important issue for tumor therapy including photodynamic therapy (PDT). The purpose of our study is to increase the targeting efficiency of photosensitizer (PS) using folate-modified nanoparticles (NPs) to tumor site in vivo. Folate receptor is over-expressed on the surface of many human cancer cells. We prepared poly (lactic-co-glycolic acid) (PLGA) NPs containing pheophorbide a (Pba), a PS that is used in PDT and generates free radical for killing cancer cells. The surface of NPs was composed of phospholipids modified with polyethylene glycol (PEG) and folate (FA). The size of the resulting FA-PLGA-Pba NPs was about 200â¯nm in PBS at pH 7.4 and they were stable for long time. They showed faster cellular uptake to MKN28 human gastric cancer cell line than control PLGA-Pba NPs by high-affinity binding with folate receptors on cell surface. In MTT assay, FA-PLGA-Pba NPs also showed enhanced tumor cell killing compared to control PLGA-Pba NPs. In vivo and ex vivo imaging showed high accumulation of FA-PLGA-Pba NPs in tumor site during 24â¯h after intravenous injection to MKN28 tumor-bearing mice model. These results demonstrate that our FA-PLGA-Pba NPs are useful for tumor-targeted delivery of PS for cancer treatment by PDT.
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Clorofila/análogos & derivados , Ácido Fólico/química , Ácido Láctico/química , Nanopartículas/química , Fármacos Fotosensibilizantes/administración & dosificación , Ácido Poliglicólico/química , Neoplasias Gástricas/tratamiento farmacológico , Animales , Línea Celular Tumoral , Clorofila/administración & dosificación , Clorofila/farmacocinética , Clorofila/uso terapéutico , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Humanos , Ratones Desnudos , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacocinética , Fármacos Fotosensibilizantes/uso terapéutico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Neoplasias Gástricas/patologíaRESUMEN
Chlorin-based photosensitizers are commonly used in photodynamic therapy (PDT). These drugs are effluxed by cell membrane transporters, such as the ATP-binding cassette subfamily G member 2 (ABCG2). PDT efficacy is limited in tumor cells expressing high levels of these proteins. Pancreatic cancer cell lines AsPC-1 and MIA PaCa-2, which have high and low ABCG2 expression, respectively, were used, and ABCG2-overexpressing MIA PaCa-2 cells were generated. We compared PDT efficacy between chlorin e6 (Ce6) and cationic photosensitizer-encapsulated polymeric nanoparticle (PS-pNP), which is comprised with Ce6, polyethylene glycol, and polyethylenimine. The intracellular concentration of Ce6 was significantly higher in MIA PaCa-2 cells than in AsPC-1 or ABCG2-overexpressing MIA PaCa-2 cells. PS-pNP increased intracellular levels of the photosensitizer in all cell lines. The cell viability experiments indicated increased Ce6 resistance in ABCG2-overexpressing cells. In contrast, PS-pNP produced similar levels of cytotoxicity in each of the cancer cell lines tested. Singlet oxygen production was higher in cells treated with PS-pNP than in those treated with Ce6. Furthermore, in heterotopic and orthotopic AsPC-1 xenograft mouse models, PDT using PS-pNP significantly reduced tumor volume in comparison with that of Ce6 treatment. PS-pNP could increase intracellular Ce6 concentration, which was related with reduced ABCG2-mediated efflux of Ce6, thereby enhancing the effects of PDT in pancreatic cancer cells. Mol Cancer Ther; 16(8); 1487-96. ©2017 AACR.
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Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Nanopartículas/química , Neoplasias Pancreáticas/tratamiento farmacológico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Polímeros/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Clorofilidas , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Porfirinas/química , Oxígeno Singlete/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The effective dosimetry for photodynamic therapy (PDT) can be specified by direct measurement of singlet oxygen ((1)O2) production. The purpose of this study was to investigate the feasibility of a newly developed photomultiplier tube (PMT)-based singlet oxygen detection (SOD) system. The lowest and highest (1)O2 concentrations detectable by the PMT-SOD system were 15nM and 10µM, respectively. Dose-dependent quenching, by NaN3, of the fluorogenic reaction was observed, which was negatively correlated with the (1)O2 level measured by the PMT-SOD system. The lifetime of (1)O2, as measured by the PMT-SOD system, was found to be lengthened when H2O was replaced with deuterium oxide. (1)O2 photon counts were significantly and dose-dependently correlated with intracellular fluorescence intensity after photosensitizer treatments. In vitro cell viability test and in vivo xenografted-tumor mass shrinkage showed a positive association between PDT-induced cytotoxicity and (1)O2 production concomitantly measured by the PMT-SOD system. It was concluded that the PMT-SOD system is capable of measuring (1)O2 production directly and accurately, demonstrating that this system can be useful in the determination of dosimetry for PDT.
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Oxígeno Singlete/análisis , Línea Celular Tumoral , Humanos , Límite de Detección , Espectrometría de FluorescenciaRESUMEN
BACKGROUND: Photodynamic therapy (PDT) contains a photosensitizing process, which includes cellular uptake of photosensitizer and delivery of light to the target. ATP-binding cassette subfamily G2 (ABCG2) regulates endogenous protoporphyrin levels. In human colon cancers, it is not fully examined the role of ABCG2 in porphyrin-based photodynamic therapy. METHODS: SW480 and HT29 cells were selected because they showed low and high ABCG2 expression levels, respectively. Pyropheophorbid-a (PPa) was used as a photosensitizer. Cells were exposed to a 670 nm diod laser. Cell viability and necrosi apoptosis was examined. Production level of singlet oxygen was detected with the photomultiplier-tube s/ -based singlet oxygen detection system. RESULTS: SW480 cells, which expressed lower level of ABCG2, showed the higher uptake of PPa than HT-29 cells. The uptake level of PPa was significantly correlated with the decreased cell viability after PDT. Pretreatment with a ABCG2 inhibitor, Ko-143, significantly enhanced the PDT efficacy in HT29 cells compared to vehicle-pretreated cells. To confirm the ABCG2 effect on PDT, we established ABCG2 over-expressing stable cells in SW480 cells (SW480/ABCG2). Furthermore, SW480/ABCG2 cells showed significantly decreased PDT effect compared to the control cells. The increased or decreased cell survival was significantly correlated with the production level of singlet oxygen after PDT. CONCLUSION: ABCG2 plays an important role in determining the PDT efficacy by controlling the photosensitizer efflux rate. This implies the control of ABCG2 expression may be a potential solution to enhance photosensitivity.