Antitumor effects of a novel photosensitizer-mediated photodynamic therapy and its influence on the cell transcriptome

Photodynamic therapy(PDT)is a promising cancer treatment.This study investigated the antitumor effects and mechanisms of a novel photosensitizer meso-5-[ρ-diethylene triamine pentaacetic acid-aminophenyl]−10,15,20-triphenyl-porphyrin(DTP)mediated PDT(DTP-PDT).Cell viability,reactive oxygen species(ROS),and apoptosis were measured with a Cell Counting Kit-8 assay,DCFH-DA fluorescent probe,and Hoechst staining,respectively.Cell apoptosis-and autophagy-related proteins were examined using western blotting.RNA sequencing was used to screen differentially expressed mRNAs(DERs),and bioinformatic analysis was performed to identify the major biological events after DTP-PDT.Our results show that DTP-PDT inhibited cell growth and induced ROS generation in MCF-7 and SGC7901 cells.The ROS scavenger N-acetyl-L-cysteine(NAC)and the P38 MAPK inhibitor SB203580 alleviated DTP-PDT-induced cytotoxicity.DTP-PDT induced cell apoptosis together with upregulated Bax and downregulated Bcl-2,which could also be inhibited by NAC or SB203580.The level of LC3B-Ⅱ,a marker of autophagy,was increased by DTP-PDT.A total of 3496 DERs were obtained after DTP-PDT.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that DERs included those involved in cytosolic ribosomes,the nuclear lumen,protein binding,cell cycle,protein targeting to the endoplasmic reticulum,and ribosomal DNA replication.Disease Ontology and Reactome enrichment analyses indicated that DERs were associated with a variety of cancers and cell cycle checkpoints.Protein-protein interaction results demonstrated that cdk1 and rps27a ranked in the top 10 interacting genes.Therefore,DTP-PDT could inhibit cell growth and induce cell apoptosis and autophagy,partly through ROS and the P38 MAPK signaling pathway.Genes associated with the cell cycle,ribosomes,DNA replication,and protein binding may be the key changes in DTP-PDT-mediated cytotoxicity.

Establishment of NaLuF_(4):15%Tb-based low dose X-PDT agent and its application on efficient antitumor therapy

X-ray excited photodynamic therapy(X-PDT)is the bravo answer of photodynamic therapy(PDT)for deep-seated tumors,as it employs X-ray as the irradiation source to overcome the limitation of light penetration depth.However,high X-ray irradiation dose caused organ lesions and side effects became the major barrier to X-PDT application.To address this issue,this work employed a classic-al co-precipitation reaction to synthesize NaLuF_(4):15%Tb^(3+)(NLF)with an average particle size of(23.48±0.91)nm,which was then coupled with the photosensitizer merocyanine 540(MC540)to form the X-PDT system NLF-MC540 with high production of singlet oxygen.The system could induce antitumor efficacy to about 24%in relative low dose X-ray irradiation range(0.1-0.3 Gy).In vivo,when NLF-MC540 irradiated by 0.1 Gy X-ray,the tumor inhibition percentage reached 89.5%±5.7%.The therapeutic mechanism of low dose X-PDT was found.A significant increase of neutrophils in serum was found on the third day after X-PDT.By immunohistochemical staining of tumor sections,the Ly6G^(+),CD8^(+),and CD11c^(+)cells infiltrated in the tumor microenvironment were studied.Utilizing the bilat-eral tumor model,the NLF-MC540 with 0.1 Gy X-ray irradiation could inhibit both the primary tumor and the distant tumor growth.De-tected by enzyme linked immunosorbent assay(ELISA),two cytokines IFN-γand TNF-αin serum were upregulated 7 and 6 times than negative control,respectively.Detected by enzyme linked immune spot assay(ELISPOT),the number of immune cells attributable to the IFN-γand TNF-αlevels in the group of low dose X-PDT were 14 and 6 times greater than that in the negative control group,respectively.Thus,it conclude that low dose X-PDT system could successfully upregulate the levels of immune cells,stimulate the secretion of cy-tokines(especially IFN-γand TNF-α),activate antitumor immunity,and finally inhibit colon tumor growth.

Codelivery of anti-CD47 antibody and chlorin e6 using a dual pH-sensitive nanodrug for photodynamic immunotherapy of osteosarcoma

Osteosarcoma is a malignant tumor originating from bone tissue that progresses rapidly and has a poor patient prognosis.Immunotherapy has shown great potential in the treatment of osteosarcoma.However,the immunosuppressive microenvironment severely limits the efficacy of osteosarcoma treatment.The dual pH-sensitive nanocarrier has emerged as an effective antitumor drug delivery system that can selectively release drugs into the acidic tumor microenvironment.Here,we prepared a dual pH-sensitive nanocarrier,loaded with the photosensitizer Chlorin e6(Ce6)and CD47 monoclonal antibodies(aCD47),to deliver synergistic photodynamic and immunotherapy of osteosarcoma.On laser irradiation,Ce6 can generate reactive oxygen species(ROS)to kill cancer cells directly and induces immunogenic tumor cell death(ICD),which further facilitates the dendritic cell maturation induced by blockade of CD47 by aCD47.Moreover,both calreticulin released during ICD and CD47 blockade can accelerate phagocytosis of tumor cells by macrophages,promote antigen presentation,and eventually induce T lymphocyte-mediated antitumor immunity.Overall,the dual pH-sensitive nanodrug loaded with Ce6 and aCD47 showed excellent immune-activating and anti-tumor effects in osteosarcoma,which may lay the theoretical foundation for a novel combination model of osteosarcoma treatment.

Anti-PD1 antibody and not anti-LAG-3 antibody improves the antitumor effect of photodynamic therapy for treating metastatic breast cancer

Photodynamic therapy(PDT)has limited effects in treating metastatic breast cancer.Immune checkpoints can deplete the function of immune cells;however,the expression of immune checkpoints after PDT is unclear.This study investigates whether the limited e±cacy of PDT is due to upregulated immune checkpoints and tries to combine the PDT and immune checkpoint inhibitor to observe the e±cacy.A metastatic breast cancer model was treated by PDT mediated by hematoporphyrin derivatives(HpD-PDT).The anti-tumor effect of HpD-PDT was observed,as well as CD4þT,CD8þT and calreticulin(CRT)by immunohistochemistry and immunofluorescence.Immune checkpoints on T cells were analyzed byflow cytometry after HpD-PDT.When combining PDT with immune checkpoint inhibitors,the antitumor effect and immune effect were assessed.For HpD-PDT at 100 mW/cm2 and 40,60 and 80 J/cm2,primary tumors were suppressed and CD4þT,CD8þT and CRT were elevated;however,distant tumors couldn't be inhibited and survival could not be prolonged.Immune checkpoints on T cells,especially PD1 and LAG-3 after HpD-PDT,were upregulated,which may explain the reason for the limited HpD-PDT effect.After PDT combined with anti-PD1 antibody,but not with anti-LAG-3 antibody,both the primary and distant tumors were signi-cantly inhibited and the survival time was prolonged,additionally,CD4þT,CD8þT,IFN-þCD4þT and TNF-þCD4þT cells were signi-cantly increased compared with HpD-PDT.HpD-PDT could not combat metastatic breast cancer.PD1 and LAG-3 were upregulated after HpD-PDT.Anti-PD1 antibody,but not anti-LAG-3 antibody,could augment the antitumor effect of HpD-PDT for treating metastatic breast cancer.

Potential of photodynamic therapy in the management of infectious oral diseases

Photodynamic therapy(PDT)can take place in the presence of three elements:Light with an appropriate wavelength;a photosensitizer;and the presence of oxygen.This type of treatment is very effective overall against bacterial,viral and mycotic cells.In the last 10 years many papers have been published on PDT with different types of photosensitizers(e.g.,methylene blue,toluidine blue,indocyanine green,curcumin-based photosensitizers),different wavelengths(e.g.,460 nm,630 nm,660 nm,810 nm)and various parameters(e.g.,power of the light,time of illumination,number of sessions).In the scientific literature all types of PDT seem very effective,even if it is difficult to find a standard protocol for each oral pathology.PDT could be an interesting way to treat some dangerous oral infections refractory to common pharmacological therapies,such as candidiasis from multidrug-resistant Candida spp.

Innovative strategies for photodynamic therapy against hypoxic tumor

Photodynamic therapy(PDT)is applied as a robust therapeutic option for tumor,which exhibits some advantages of unique selectivity and irreversible damage to tumor cells.Among which,photosensitizer(PS),appropriate laser irradiation and oxygen(O_(2))are three essential components for PDT,but the hypoxic tumor microenvironment(TME)restricts the O_(2) supply in tumor tissues.Even worse,tumor metastasis and drug resistance frequently happen under hypoxic condition,which further deteriorate the antitumor effect of PDT.To enhance the PDT efficiency,critical attention has been received by relieving tumor hypoxia,and innovative strategies on this topic continue to emerge.Traditionally,the O_(2) supplement strategy is considered as a direct and effective strategy to relieve TME,whereas it is confronted with great challenges for continuous O_(2) supply.Recently,O_(2)-independent PDT provides a brand new strategy to enhance the antitumor efficiency,which can avoid the influence of TME.In addition,PDT can synergize with other antitumor strategies,such as chemotherapy,immunotherapy,photothermal therapy(PTT)and starvation therapy,to remedy the inadequate PDT effect under hypoxia conditions.In this paper,we summarized the latest progresses in the development of innovative strategies to improve PDT efficacy against hypoxic tumor,which were classified into O_(2)-dependent PDT,O_(2)-independent PDT and synergistic therapy.Furthermore,the advantages and deficiencies of various strategies were also discussed to envisage the prospects and challenges in future study.

Nanoparticle-mediated synergistic anticancer effect of ferroptosis and photodynamic therapy:Novel insights and perspectives

Current antitumor monotherapy has many limitations,highlighting the need for novel synergistic anticancer strategies.Ferroptosis is an iron-dependent form of nonapoptotic cell death that plays a pivotal regulatory role in tumorigenesis and treatment.Photodynamic therapy(PDT)causes irreversible chemical damage to target lesions and is widely used in antitumor therapy.However,PDT’s effectiveness is usually hindered by several obstacles,such as hypoxia,excess glutathione(GSH),and tumor resistance.Ferroptosis improves the anticancer efficacy of PDT by increasing oxygen and reactive oxygen species(ROS)or reducing GSH levels,and PDT also enhances ferroptosis induction due to the ROS effect in the tumor microenvironment(TME).Strategies based on nanoparticles(NPs)can subtly exploit the potential synergy of ferroptosis and PDT.This review explores recent advances and current challenges in the landscape of the underlyingmechanisms regulating ferroptosis and PDT,as well as nano delivery system-mediated synergistic anticancer activity.These include polymers,biomimetic materials,metal organic frameworks(MOFs),inorganics,and carrier-free NPs.Finally,we highlight future perspectives of this novel emerging paradigm in targeted cancer therapies.

Photodynamic therapy with TBZPy regulates the PI3K/AKT and endoplasmic reticulum stress-related PERK/eIF2α pathways in HeLa cells

Background:((1-triphenylaminebenzo[c][1,2,5]thiadiazole-4-yl)styryl)-1-methylpyridin methylpyridin-1-ium iodide salt(TBZPy)is a novel photosensitizer that displays excellent photodynamic properties.However,There are few reports on the mechanism of action of the TBZPy photodynamic.Previous studies revealed that photodynamic therapy(PDT)could induce endoplasmic reticulum stress by acting on the endoplasmic reticulum.Therefore,in this study,we investigated the effects of endoplasmic reticulum stress induced by TBZPy-PDT in treating High-risk human papillomavirus(HR-HPV)infection and their underlying mechanisms.Methods:The human cervical cancer cell line HeLa(containing whole genome of HR-HPV18)was treated with TBZPy-PDT.Cell migration,invasion,and colony-forming ability were evaluated using wound-healing,Transwell invasion,and colonyforming assays,respectively.Through western blot analysis,we determined the level of expression of the PI3K/AKT and PERK/eIF2αpathway proteins and the proteins associated with calcium trafficking and apoptosis.The calcium levels in the cytoplasm were detected via flow cytometry.Results:The result shows that TBZPy-PDT could inhibite the migration,invasion,and colony forming ability of infected HeLa cells by downregulating the PI3K/AKT pathway in vitro.And we found that TBZPy-PDT induced endoplasmic reticulum stress-specific apoptosis via the PERK/eIF2αpathway.Moreover,TBZPy-PDT increased the levels of calcium and calmodulin,while decreasing the levels of endoplasmic reticulum calcium-binding proteins.Conclusions:TBZPy-PDT is effective on treating human papillomavirus-infected cells.Targeting the PI3K/AKT and PERK/eIF2αpathways and the endoplasmic reticulum stress process may help improve the effects of TBZPy-PDT for treating high-risk human papillomavirus infection.

Advances in photodynamic therapy for port-wine stain and our experience

Port-wine stain(PWS)is a congenital capillary malformation that occurs in 0.3%–0.5%of newborns.The pulsed dye laser is the current gold standard treatment for PWS;however,its efficacy is poor.Photosensitizer photodynamic therapy(PDT)is considered a promising treatment for PWS.Here we provide a comprehensive overview of PDT.

Study of Effects of Photodynamic Therapy(PDT),in Scar-Induced Skin Wounds in Rats Wistar:The New Clinical Perspective for Ulcers

Photodynamic therapy today is becoming an important role in the healing of lacerated tissues, since it has therapeutic resources capable of accelerating this process. One treatment option is the clinical phototherapy, and Photodynamic Therapy (PDT) is being widely used. This study aims to evaluate the effect of PDT on the healing of skin wounds in rats. We used a sample of 39 male rats Wistar divided into three groups, a control, a PDT-treated green and red with the last PDT. After 24 hours before the surgical incisions, PDT was used in both groups for 6 minutes and was evaluated in histological level, the inflammatory reaction and the repair process. The results showed that the granulation tissue was more developed in the irradiated group than in the control group and the amount of chronic inflammatory cells (monocytes, macrophages, lymphocytes and plasma cells) predominated with green phototherapy. The epithelialization in the wound margins and scarring with better quality occurred with red PDT (640 nm), which the higher deposition was of collagen. However, phototherapy not collimated of 640 nm (red) resulted in better anti-inflammatory effects. Given these answers with phototherapy not collimated green (525 nm) and red (640 nm), we conclude that the use of these wavelengths is possible with benefits, mainly with red LED.

ALA-PDT、卡介菌多糖核酸注射液联合胸腺肽肠溶片治疗尖锐湿疣的效果

目的研究艾拉光动力治疗(ALA-PDT)、卡介菌多糖核酸注射液联合胸腺肽肠溶片治疗尖锐湿疣的效果。方法选取2020年2月至2022年6月郑州大学附属郑州中心医院收治的82例尖锐湿疣患者为研究对象,以随机双盲法分为联合组、对照组,各41例。对照组接受胸腺肽肠溶片联合ALA-PDT治疗,联合组在对照组基础上接受卡介菌多糖核酸注射液治疗。比较两组临床疗效、治疗前和治疗3个月后疣体数、皮损面积、免疫功能指标(CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+))、血清细胞因子[脂质过氧化物(Lpo)、粒细胞-巨噬细胞集落刺激因子(GM-CSF)、超敏C反应蛋白(hs-CRP)、肿瘤坏死因子-α(TNF-α)]水平、6个月复发率。结果联合组临床总有效率高于对照组(P<0.05);治疗3个月后,联合组疣体数、皮损面积小于对照组(P<0.05);治疗3个月后与对照组相比,联合组CD3^(+)、CD4^(+)/CD8^(+)、CD4^(+)水平较高,CD8^(+)水平较低(P<0.05);治疗3个月后,联合组血清GM-CSF、TNF-α、Lpo、hs-CRP水平低于对照组(P<0.05);治疗后随访6个月,联合组复发率(2.56%)低于对照组(21.05%)(P<0.05)。结论采用ALA-PDT、卡介菌多糖核酸注射液与胸腺肽肠溶片联合治疗可促进尖锐湿疣患者免疫功能改善,抑制炎症反应,减轻临床症状,提高临床疗效,且复发风险较低。

PDT通过氧化应激增加TMZ对胶质瘤U251细胞的抑制

目的多重耐药性(multiple drug resistance,MDR)仍在替莫唑胺(temozolomide,TMZ)治疗胶质瘤过程中不可避免的出现,成为胶质瘤预后不佳和局部侵袭复发的重要原因。本研究旨在观察光动力疗法(photodynamic therapy,PDT)是否能增加人胶质瘤细胞U251对TMZ的化疗敏感度,并深入探讨其增敏机制。方法人源胶质瘤细胞U251进行常规体外培养,根据处理方法分为5组,即对照(control)组、TMZ组、PDT组、TMZ+激光(TMZ+Laser)组和PDT+TMZ组,应用CCK-8观察U251细胞活性、Transwell小室观察细胞侵袭能力、免疫荧光观察细胞内活性氧(reactive oxygen species,ROS)及线粒体膜电位(mitochondrial membrane potential,MMP)水平,结果数据用GraphPad Prism软件统计分析。结果CCK-8实验表明在TMZ处理后8h,即产生了U251细胞对TMZ的治疗抵抗。PDT协同应用于TMZ处理8h的U251细胞后,PDT+TMZ组光密度(OD)值、侵袭细胞数量、MMP水平与control组和TMZ组比较均降低,而ROS升高,进一步分析表明,ROS和MMP水平呈负相关(r=-0.559,P<0.05)。结论PDT通过提高TMZ作用后的胶质瘤U251细胞内的ROS总量,加强了对U251细胞增殖和侵袭能力的抑制,延缓了MDR的发生。

Influence of Photodynamic Therapy on Apoptosis and Invasion of Human Cholangiocarcinoma QBC939 Cell Line

Objective To investigate the effect of photodynamic therapy(PDT) mediated by hematoporphyrin derivative(HPD) on apoptosis and invasion of cholangiocarcinoma QBC939 cell lines. Methods In vitro cultured cholangiocarcinoma QBC939 cell line was exposed to 2, 4, 6, 8, 10, 12, and 14 μg/ml HPD with 5, 10, and 15 J/cm2 light intensity, respectively. The optical density at 450 nm of the QBC939 cells was measured by CCK8 assay and its growth inhibition ratio was calculated. Flow cytometry and transwell migration assay were applied to detect cell apoptosis and invasion respectively. RT-PCR and immunocytochemistry analyses were used to detect expressions of vascular endothelial growth factor-C(VEGF-C), cyclooxygenase-2(COX-2), and proliferating cell nuclear antigen(PCNA). Enzyme-linked immunosorbent assay(ELISA) was carried out to examine the secretion of VEGF-C and COX-2 in QBC939 cells. Results Exposure to HPD-PDT can significantly suppress the growth of QBC939 cells(all P<0.05). HPD-PDT can promote apoptosis of QBC939 cells at the early stage. When the concentration of HPD was 2 μg/ml and light irradiation was 5 J/cm2, HPD-PDT had no obvious inhibitory effect on QBC939 cell growth, but can obviously inhibit cell invasion, and significant difference was observed between the HPD-PDT and control groups(P<0.01). The HPD-PDT can reduce the m RNA and protein expressions of VEGF-C, COX-2, and PCNA, and decrease the secretion of VEGF-C and COX-2 in QBC939 cells. Conclusion PDT could promote apoptosis and inhibit growth and invasion of cholangiocarcinoma cells QBC939 in vitro.

光动力疗法基础研究进展——浅谈ALA-PDT增效策略

5-氨基酮戊酸(5-aminolevulinic acid,ALA)是血红素生物合成的前体,在线粒体中形成原卟啉IX(protoporphyrin IX,PpIX),PpIX的特征性荧光可用于辅助手术和光动力诊断,PpIX介导形成的单态氧所导致的光敏作用可用于光动力疗法(photodynamictherapy,PDT)。本综述结合基础研究进展,对具有临床应用可行性的ALA-PDT增效策略做一系统介绍。

Photodynamic therapy vs radiofrequency ablation for Barrett's dysplasia: Efficacy,safety and cost-comparison

AIM:To compare effectiveness,safety,and cost of photodynamic therapy(PDT)and radiofrequency ablation(RFA)in treatment of Barrett’s dysplasia(BD).METHODS:Consecutive case series of patients undergoing either PDT or RFA treatment at single center by a single investigator were compared.Thirty-three patients with high-grade dysplasia(HGD)had treatment with porfimer sodium photosensitzer and 630 nm laser(130 J/cm),with maximum of 3 treatment sessions.Fifty-three patients with BD(47 with low-grade dysplasia-LGD,6 with HGD)had step-wise circumferential and focal ablation using the HALO system with maximum of 4 treatment sessions.Both groups received proton pump inhibitors twice daily.Endoscopic biopsies were acquired at 2 and 12 mo after enrollment,with 4-quadrant biopsies every 1 cm of the original BE extent.A complete histological resolution response of BD(CR-D)was defined as all biopsies at the last endoscopy session negative for BD.Fisher’s exact test was used to assess differences between the two study groups for primary outcomes.For all outcomes,a two-sided P value of less than 0.05 was considered to indicate statistical significance.RESULTS:Thirty(91%)PDT patients and 39(74%)RFA were men(P=0.05).The mean age was 70.7±12.2 and 65.4±12.7(P=0.10)year and mean length of BE was 5.4±3.2 cm and 5.7±3.2 cm(P=0.53)for PDT and RFA patients,respectively.The CR-D was(18/33)54.5%with PDT vs(47/53)88.7%with RFA(P=0.001).One patient with PDT had an esophageal perforation and was managed with non-surgical measures and no perforation was seen with RFA.PDT was five times more costly than RFA at our institution.The two groups were not randomized and had different BD grading are the limitations of the study.CONCLUSION:In our experience,RFA had higher rate of CR-D without any serious adverse events and was less costly than PDT for endoscopic treatment of BD.

Recent Advances in Tumor Microenvironment Hydrogen Peroxide-Responsive Materials for Cancer Photodynamic Therapy

Photodynamic therapy(PDT),as one of the noninvasive clinical cancer phototherapies,suffers from the key drawback associated with hypoxia at the tumor microenvironment(TME),which plays an important role in protecting tumor cells from damage caused by common treatments.High concentration of hydrogen peroxide(H2O2),one of the hallmarks of TME,has been recognized as a double-edged sword,posing both challenges,and opportunities for cancer therapy.The promising perspectives,strategies,and approaches for enhanced tumor therapies,including PDT,have been developed based on the fast advances in H2O2-enabled theranostic nanomedicine.In this review,we outline the latest advances in H2O2-responsive materials,including organic and inorganic materials for enhanced PDT.Finally,the challenges and opportunities for further research on H2O2-responsive anticancer agents are envisioned.

Human natural killer cells for targeting delivery of gold nanostars and bimodal imaging directed photothermal/photodynamic therapy and immunotherapy

Objective:To construct a novel nanoplatform GNS@CaCO3/Ce6-NK by loading the CaCO3-coated gold nanostars(GNSs)with Chlorin e6 molecules(Ce6)into human peripheral blood mononuclear cells(PBMCs)-derived NK cells for tumor targeted therapy.Methods:GNS@CaCO3/Ce6 nanoparticles were prepared and characterized by TEM and UV-vis.The cell surface markers and cytokines secretion of NK cells before and after loading the GNS@CaCO3/Ce6 nanoparticles were detected by Flow Cytometry(FCM)and ELISA.Effects of the GNS@CaCO3/Ce6-NK cells on A549 cancer cells was determined by FCM and CCK-8.Intracellular fluorescent signals of GNS@CaCO3/Ce6-NK cells were detected via Confocal laser scanning microscopic(CLSM)and FCM at different time points.Intracellular ROS generation of GNS@CaCO3/Ce6-NK cells under laser irradiation were examined by FCM.The distribution of GNS@CaCO3/Ce6-NK in A549 tumor-bearing mice were observed by fluorescence imaging and PA imaging.The combination therapy of GNS@CaCO3/Ce6-NK under laser irradiation were investigated on tumor-bearing mice.Results:The coated CaC03 shell on the surface of GNSs exhibited prominent delivery and protection effect of Ce6 during the cellular uptake process.The as-prepared multifunctional GNS@CaCO3/Ce6-NK cells possessed bimodal functions of fluorescence imaging and photoacoustic imaging.The as-prepared multifunctional GNS@CaCO3/Ce6-NK cells could actively target tumor tissues with the enhanced photothermal/photodynamic therapy and immunotherapy.Conclusions:The GNS@CaCO3/Ce6-NK shows effective tumor-targeting ability and prominent therapeutic efficacy toward lung cancer A549 tumor-bearing mice.Through fully utilizing the features of GNSs and NK cells,this new nanoplatform provides a new synergistic strategy for enhanced photothermal/photodynamic therapy and immunotherapy in the field of anticancer development in the near future.

Photodynamic therapy for high-grade dysplasia of bile duct via a choledochoscope

When a distal common bile duct neoplasm is at the stage of carcinoma in situ or high-grade dysplasia,it is difficult for the surgeon to decide whether to perform pancreaticoduodenectomy.Here we describe a patient with a progressive dysplastic lesion in the common bile duct,which developed from moderate-high to highgrade dysplasia in approximately 2 mo.The patient refused major surgery.Therefore,endoscopic-assisted photodynamic therapy was performed.The result at follow-up using a trans-T-tube choledochoscope showed that the lesion was completely necrotic.This report is the first to describe the successful treatment of highgrade dysplasia of the distal bile duct using photodynamic therapy via a choledochoscope.

Photodynamic therapy:Palliation and endoscopic technique in cholangiocarcinoma

Cholangiocarcinoma is the primary malignancy arising from the biliary epithelium.The disease is marked by jaundice,cholestasis,and cholangitis.Over 50 percent of patients present with advanced stage disease,precluding curative surgical resection as an option of treatment.Prognosis is poor,and survival has been limited even after biliary decompression.Palliative management has become the standard of care for unresectable disease and has evolved to include an endoscopic approach. Photodynamic therapy(PDT)consists of administration of a photosensitizer followed by local irradiation with laser therapy.Several studies conducted in Europe and the United States have shown a marked improvement in the symptoms of cholestasis,survival,and quality of life.This article summarizes the published experience regarding PDT for cholangiocarcinoma and the steps required to administer this therapy safely.

Combined therapy with bevacizumab and photodynamic therapy for myopic choroidal neovascularization: A oneyear follow-up controlled study

AIMTo evaluate the efficacy and safety of a combined treatment for myopic choroidal neovascularization (CNV) using photodynamic therapy (PDT) and intravitreal bevacizumab and to compare it with intravitreal bevacizumab monotherapy.