Selective accumulation of PpIX and photodynamic effect after aminolevulinic acid treatment of human adenomyosis xenografts in nude mice.

PubMed

Suzuki-Kakisaka, Haruka; Murakami, Takashi; Hirano, Toru; Terada, Yukihiro; Yaegashi, Nobuo; Okamura, Kunihiro

2008-10-01

To evaluate the effect of photodynamic therapy with aminolevulinic acid (ALA) on human adenomyosis xenografts in a mouse model. Human adenomyosis tissues were implanted SC into nude mice. We measured 5-aminolevulinic acid pharmacokinetics in these mice by analyzing tissue sections 1 to 6 hours after intraperitoneal administration. Twenty-four hours after photodynamic therapy, we evaluated tissue morphologic features. Department of obstetrics and gynecology at a university hospital in Japan. Immunodeficient mice. Tissue grafts were taken from women with adenomyosis attending a university hospital. Photodynamic treatment. Peak fluorescence after intraperitoneal ALA administration and tissue histological changes 24 hours after photodynamic therapy. Peak fluorescence was observed 3 hours after intraperitoneal administration. Histological studies revealed decreased numbers of epithelial and stromal cells in adenomyosis models after therapy. Photodynamic therapy with ALA caused extensive cell death in human adenomyosis tissues implanted into nude mice. Photodynamic treatment using ALA is a potential treatment for patients with adenomyosis uteri.

Ambulant photodynamic therapy of superficial malignomas with 5-ALA in combination with folic acid and use of noncoherent light.

PubMed

Jindra, R H; Kubin, A; Kolbabek, H; Alth, G; Dobrowsky, W

1999-01-01

This study reports our first results of ambulant photodynamic treatment with 5-aminolevulinic acid (5-ALA) in combination with folic acid and subsequent illumination with a noncoherent light source. The compound was topically applied to avoid total body skin sensitivity which occurs in the case of systemic administration. If no therapeutic response could be proved, we added folic acid to 5-ALA for a further treatment attempt. Illumination was performed by broad band red thermic light to also excitate reaction products with absorption bands located near to that of the sensitizer. As a result, we observed a response in all cases, however, in some cases only after the addition of folic acid.

Aminolevulinic acid-mediated protoporphyrin IX and photodynamic therapy for breast cancers (Conference Presentation)

NASA Astrophysics Data System (ADS)

Chen, Bin

2017-02-01

Photodynamic therapy (PDT) involves the combination of a photosensitizer and light of a specific wavelength. Upon light activation in the presence of oxygen, photosensitizer molecules generate reactive oxygen species that cause cytotoxicity by inducing oxidative stress. Aminolevulinic acid (ALA) is a pro-drug used for the diagnosis and PDT treatment of various solid tumors based on endogenous production of heme precursor protoporphyrin IX (PpIX). Although nearly all types of human cells express heme biosynthesis enzymes and produce PpIX, tumor cells are found to have more PpIX production and accumulation than normal cells, allowing for the detection and treatment of solid tumors. The objective of my research is to explore therapeutic approaches to enhance ALA-based tumor detection and therapy. We have found that high ABCG2 transporter activity in triple negative breast cancer cells (TNBC) contributed to reduced PpIX levels in cells, causing them to be more resistant towards ALA-PDT. The administration of an ABCG2 inhibitor, Ko143, was able to reverse cell resistance to ALA-PDT by enhancing PpIX mitochondrial accumulation and sensitizing cancer cells to ALA-PDT. Ko143 treatment had little effect on PpIX production and ALA-PDT in normal and ER- or HER2-positive cells. Furthermore, since some tyrosine kinase inhibitors (TKI) are known to block ABCG2 transporter activity, we screened a panel of tyrosine kinase inhibitors to examine its effect on enhancing PpIX fluorescence and ALA-PDT efficacy. Several TKIs including lapatinib and gefitinib showed effectiveness in increasing ALA-PpIX fluorescence in TNBC leading to increased cell death after PDT administration. These results indicate that inhibiting ABCG2 transporter using TKIs is a promising approach for targeting TNBC with ALA-based modality.

Photodynamic Therapy (PDT) using intratumoral injection of the 5- aminolevulinic acid (5-ALA) for the treatment of eye cancer in cattle

NASA Astrophysics Data System (ADS)

Hage, Raduan; Mancilha, Geraldo; Zângaro, Renato A.; Munin, Egberto; Plapler, Hélio

2007-02-01

A six-year old Holstein cow with an eye cancer (ocular squamous cell carcinoma) involving the third eyelid and conjunctiva was submitted to photodynamic therapy using intratumoral 20% aminolevulinic acid (5-ALA - Aldrich Chemical Company, Milwaukee, USA) and a light emitting diode (LED - VET LED - MMOptics (R)) with wavelength between 600 and 700 nm, 2 cm diameter circular light beam, power of 150 mW, light dose of 50 J/cm2 as a source of irradiation. Fifteen days after the experimental procedure we observed about 50% tumor reduction and complete remission after 3 months. Relapse was not observed up to 12 months after the treatment. Although the study only includes one animal not allowing definite conclusions, it indicates that PDT represents a safe and technically feasible approach in the treatment of eye cancer in cattle.

Preclinical studies of photodynamic therapy of intracranial tissues

NASA Astrophysics Data System (ADS)

Lilge, Lothar D.; Sepers, Marja; Park, Jane; O'Carroll, Cindy; Pournazari, Poupak; Prosper, Joe; Wilson, Brian C.

1997-05-01

The applicability and limitations of the photodynamic threshold model were investigated for an intracranial tumor (VX2) and normal brain tissues in a rabbit model. Photodynamic threshold values for four different photosensitizers, i.e., Photofrin, 5(delta) -aminolaevulinic acid (5(delta) -ALA) induced Protoporphyrin IX (PPIX), Tin Ethyl Etiopurpurin (SnET2), and chloroaluminum phthalocyanine (AlClPc), were determined based on measured light fluence distributions, macroscopic photosensitizer concentration in various brain structures, and histologically determined extent of tissue necrosis following PDT. For Photofrin, AlClPc, and SnET2, normal brain displayed a significantly lower threshold value than VX2 tumor. For 5(delta) -ALA induced PPIX and SnET2 no or very little white matter damage, equalling to very high or infinite threshold values, was observed. Additionally, the latter two photosensitizers showed significantly lower uptake in white matter compared to other brain structures and VX2 tumor. Normal brain structures lacking a blood- brain-barrier, such as the choroid plexus and the meninges, showed high photosensitizer uptake for all photosensitizers, and, hence, are at risk when exposed to light. Results to date suggest that the photodynamic threshold values iares valid for white matter, cortex and VX2 tumor. For clinical PDT of intracranial neoplasms 5(delta) -ALA induced PPIX and SnET2 appear to be the most promising for selective tumor necrosis.However, the photosensitizer concentration in each normal brain structure and the fluence distribution throughout the treatment volume and adjacent tissues at risk must be monitored to maximize the selectivity of PDT for intracranial tumors.

A Retrospective Review of Pain Control by a Two-Step Irradiance Schedule During Topical ALA-Photodynamic Therapy of Non-melanoma Skin Cancer

PubMed Central

Zeitouni, Nathalie C.; Paquette, Anne D.; Housel, Joseph P.; Shi, Yi; Wilding, Gregory; Foster, Thomas H.; Henderson, Barbara W.

2013-01-01

Background and Objective Photodynamic therapy (PDT) with topical δ-aminolevulinic acid (ALA) of non-melanoma skin cancers is often associated with treatment-limiting pain. A previous study on basal cell carcinomas (BCCs) at Roswell Park Cancer Institute evaluated a two-step irradiance scheme as a means of minimizing pain, preserving outcomes, and limiting treatment time. We used an initial low irradiance until 90% of the protoporphyrin IX was photobleached, followed by a high irradiance interval until the prescribed fluence was delivered. Success of this pilot investigation motivated integration of the protocol into routine practice. Here we present a retrospective review of recent clinical experience in a broad patient population. Study Design/Materials and Methods This was a retrospective review of an existing dermatology data base. Fourteen caucasion patients - 9 men and 5 women, ages 18 to 80, with a total of 51 superficial and 73 nodular BCCs, and three Bowen's disease lesions – were included. ALA was applied to each lesion for approximately 4h. Lesions received an initial irradiance of 30 - 50 mW/cm2 for 20 J/cm2, followed by 150 mW/cm2 for a total fluence of 200-300 J/cm2. Pain was assessed using a visual analog scale (VAS). Clinical outcome was determined at 6-12 months. Results Median VAS scores were 1.0 for both irradiances. Five of 127 lesions required pain control with 1% xylocaine. Pain was strongly influenced by lesion location but not by lesion type, number, or size. Complete responses were achieved in 84.1% of BCCs, which compares favorably with reported results for single ALA-PDT treatments. Two of three Bowen's disease lesions showed a complete response. Complete responses for nodular BCCs were 37%, which are also within the range of reported outcomes. Conclusions A two-step irradiance protocol in ALA-PDT effectively minimizes pain, maintains excellent clinical outcomes in superficial lesions, and adds minimal treatment time. PMID:23390058

Photodynamic therapy with 5-aminoolevulinic acid-induced porphyrins and DMSO/EDTA for basal cell carcinoma

NASA Astrophysics Data System (ADS)

Warloe, Trond; Peng, Qian; Heyerdahl, Helen; Moan, Johan; Steen, Harald B.; Giercksky, Karl-Erik

1995-03-01

Seven hundred sixty three basal cell carcinomas (BCCs) in 122 patients were treated by photodynamic therapy by 5-aminolevulinic acid (ALA) in cream topically applied, either alone, in combination with dimethyl sulphoxide (DMSO) and ethylenediaminetetraacetic acid disodium salt (EDTA), or with DMSO as a pretreatment. After 3 hours cream exposure 40 - 200 Joules/cm2 of 630 nm laser light was given. Fluorescence imaging of biopsies showed highly improved ALA penetration depth and doubled ALA-induced porphyrin production using DMSO/EDTA. Treatment response was recorded after 3 months. After a single treatment 90% of 393 superficial lesions responded completely, independent of using DMSO/EDTA. In 363 nodulo-ulcerative lesions the complete response rate increased from 67% to above 90% with DMSO/EDTA for lesions less than 2 mm thickness and from 34% to about 50% for lesions thicker than 2 mm. Recurrence rate observed during a follow-up period longer than 12 months was 2 - 5%. PDT of superficial thin BCCs with ALA-induced porphyrins and DMSO/EDTA equals surgery and radiotherapy with respect to cure rate and recurrence. Cosmetic results of ALA-based PDT seemed to be better than those after other therapies. In patients with the nevoid BCC syndrome the complete response rate after PDT was far lower.

Photodynamic therapy for cancer

MedlinePlus

... Photoradiation therapy; Cancer of the esophagus - photodynamic; Esophageal cancer - photodynamic; Lung cancer - photodynamic ... the light at the cancer cells. PDT treats cancer in the: Lungs, using a bronchoscope Esophagus, using upper endoscopy Doctors ...

Photodynamic Therapy Interventions in Facial Photodamage: A Systematic Review.

PubMed

Sanclemente, G; Ruiz-Cañas, V; Miranda, J M; Ferrín, A P; Ramirez, P A; Hernandez, G N

2018-04-01

Photodynamic therapy (PDT) involves the combination of a light source and a photosensitizing agent to induce tissue damage via the generation of singlet oxygen. Although topical PDT has been approved for other indications, its use in facial photodamage is uncertain. To assess the efficacy and safety of PDT in facial skin photoaging. All randomized clinical trials (RCTs) evaluating the efficacy and safety of any form of topical PDT for the treatment of facial photodamage (dermatoheliosis) or photoaging in patients older than 18 years, were included. Photodynamic-therapy using any topical photosensitizing agent at any dose, and with any light-source, were considered. Comparators were chemical exfoliation, intense pulsed light (IPL), light emitting diodes (LED), dermabrasion or microdermabrasion, ablative or non-ablative lasers, injectables, surgery, placebo and/or no treatment. A systematic search in PubMed, Embase, Lilacs, Google Scholar and RCT's registry databases, was performed. Search was conducted up to May 4th 2016. Four authors independently selected and assessed methodological quality of each RCT. According to inclusion criteria, twelve studies were included (6 aminolevulinate (ALA) trials and 6 methyl aminolevulinate (MAL) trials), but the majority of them had methodological constraints particularly in randomization description and patients/outcome assessors blindness. Overall results indicated that PDT either with ALA or with MAL was effective and safe for facial photodamage treatment, but high quality of evidence was found mainly for MAL studies. Copyright © 2017 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

Photodynamic therapy of non-melanoma skin cancers

NASA Astrophysics Data System (ADS)

Ikram, M.; Khan, R. U.; Firdous, S.; Atif, M.; Nawaz, M.

2011-02-01

In this prospective study duly approved from Institutional Ethics Review Committee for research in medicine, PAEC General Hospital Islamabad, Pakistan, we investigate the efficacy, safety and tolerability along with cosmetic outcome of topical 5-aminolaevulinic acid photodynamic therapy for superficial nonmelanoma skin cancers (NMSCs) and their precursors. Patients with Histological diagnosis of NMSCs and their precursors were assessed for PDT, after photographic documentation of the lesions and written consent, underwent two (2) sessions of PDT in one month (4 weeks) according to standard protocol. A freshly prepared 20% 5-ALA in Unguentum base was applied under occlusive dressing for 4-6 h as Drug Light Interval (DLI) and irradiated with light of 630 nm wavelength from a diode laser at standard dose of 90 J/cm2. Approximately 11% patients reported pain during treatment which was managed in different simple ways. In our study we regularly followed up the patients for gross as well as histopathological response and recurrence free periods during median follow-up of 24 months. Regarding Basal cell carcinomas complete response was observed in 86.2% (25/29), partial response in 10.3% (3/29) and recurrence during first year in 3.5% (1/29) lesions. All the lesions which showed partial response or recurrence were nBCCs. Regarding Actinic Keratosis complete response was observed in 95.3% (20/21), partial response in 4.7% (1/21) while Bowen's disease showed 100% (2/2) results. 81.8% (9/11) Squamous Cell Carcinomas showed complete, 9% (1/11) partial response and 9% (1/11) presented with recurrence after 3 months. We observed excellent and good cosmetic results along with tumor clearance in our study. Treatment sessions were well tolerated with high level of patient's satisfaction and only minor side effects of pain during treatment sessions and inflammatory changes post photodynamic therapy were observed. We concluded that 5-ALA PDT is an effective and safe emerging

Local anaesthetic 5-aminolaeuvulinic acid photodynamic therapy in the treatment of superficial bladder cancer

NASA Astrophysics Data System (ADS)

Shackley, David C.

The aim of this thesis was to study aspects of the treatment of superficial bladder carcinoma using photodynamic therapy by combining the delivery of laser light energy with the photosensitiser 5-aminolaeuvulinic acid (ALA). ALA is a novel pro-drug, which can be absorbed intravesically where it is converted in diseased urothelium and tumour to the active photosensitiser, PpK. Following whole bladder light irradiation there is release of toxic radicals, which are scavenged by oxygen causing selective necrosis (PDT). Preliminary studies on animals suggest that ALA is superior to earlier bladder PDT sensitisers in that generalised photosensitivity and bladder contracture are avoided. These problems in conjunction with the complexity of PDT whereby a general anaesthetic with rigid cystoscopy under continuous irrigation are required, have previously limited the development of this modality as a practical therapy. (Abstract shortened by ProQuest.).

Fluorescence-Guided Resection of Malignant Glioma with 5-ALA

PubMed Central

Kaneko, Sadahiro

2016-01-01

Malignant gliomas are extremely difficult to treat with no specific curative treatment. On the other hand, photodynamic medicine represents a promising technique for neurosurgeons in the treatment of malignant glioma. The resection rate of malignant glioma has increased from 40% to 80% owing to 5-aminolevulinic acid-photodynamic diagnosis (ALA-PDD). Furthermore, ALA is very useful because it has no serious complications. Based on previous research, it is apparent that protoporphyrin IX (PpIX) accumulates abundantly in malignant glioma tissues after ALA administration. Moreover, it is evident that the mechanism underlying PpIX accumulation in malignant glioma tissues involves an abnormality in porphyrin-heme metabolism, specifically decreased ferrochelatase enzyme activity. During resection surgery, the macroscopic fluorescence of PpIX to the naked eye is more sensitive than magnetic resonance imaging, and the alert real time spectrum of PpIX is the most sensitive method. In the future, chemotherapy with new anticancer agents, immunotherapy, and new methods of radiotherapy and gene therapy will be developed; however, ALA will play a key role in malignant glioma treatment before the development of these new treatments. In this paper, we provide an overview and present the results of our clinical research on ALA-PDD. PMID:27429612

Review of dermatology use of 5-aminolevulinic acid photodynamic therapy in China from 1997 to 2013

NASA Astrophysics Data System (ADS)

Wang, Peiru; Zhang, Guolong; Wang, Xiuli

2015-07-01

The prodrug 5-aminolevulinic acid (ALA) and its ester derivatives have been used in photodynamic therapy (PDT) in dermatology worldwide. In China, ALA-PDT was first used to treat urethral condylomata acuminata and non-melanoma skin cancers in 1997. A powder formulation of ALA hydrochloride was approved by the Chinese Food and Drug Administration for the treatment of condylomata acuminata in 2007. Large successful experience of treating condylomatas was accumulated compared with Western countries. Meanwhile, numerous clinical studies as well as off-label use of ALAPDT have been carried out in China. To reflect the progress of ALA-PDT in China, several major Chinese and English databases were searched and published data were reviewed in this article.

Photodynamic therapy: Theoretical and experimental approaches to dosimetry

NASA Astrophysics Data System (ADS)

Wang, Ken Kang-Hsin

fluorescence spectroscopy. We successfully simulate the in vivo photobleaching of PpIX in this patient population over a wide range of irradiances using the PDT model. For most cases, the rate of bleaching slows as treatment progresses, leaving a fraction of the PpIX unbleached despite sustained irradiation. To account for this feature, the model predicts that incorporation of ALA-PDT-induced blood flow reduction is necessary. In addition to using the theoretical method to understand the dose deposited by photodynamic therapy, experimentally, we propose a potential dose metric for Pc 4-PDT. Pc 4 is a promising second generation photosensitizer that is now in Phase I clinical trials for the treatment of cutaneous lesions. We have observed a significant irradiation-induced increase in Pc 4 fluorescence in tumor cell monolayers. The amount of the fluorescence increase observed in vitro strongly correlates to the cell death and mitochondrial swelling reported by the clonogenic cell survival assay and light scattering measurements, respectively. Based on those biological responses, we anticipate that irradiation-induced fluorescence enhancement in Pc 4-PDT may be a potential dose metric.

Comparison of cryotherapy and photodynamic therapy in treatment of oral leukoplakia.

PubMed

Kawczyk-Krupka, Aleksandra; Waśkowska, Jadwiga; Raczkowska-Siostrzonek, Agnieszka; Kościarz-Grzesiok, Anna; Kwiatek, Sebastian; Straszak, Dariusz; Latos, Wojciech; Koszowski, Rafał; Sieroń, Aleksander

2012-06-01

Oral leukoplakia is a pre-malignant lesion of the oral mucosa. The aim of this study is to compare the curative effects of photodynamic therapy and cryotherapy in the treatment of oral leukoplakia. The first group, treated by photodynamic therapy (δ-aminolevulinic acid (ALA), 630-635 nm wavelength), consisted of 48 patients suffering from leukoplakia. The second group consisted of 37 patients treated using cryotherapy. Analyses and comparisons of the complete responses, recurrences, numbers of procedures and adverse effects after both PDT and cryotherapy were obtained. In the first group, a complete response was obtained in 35 patients (72.9%), with thirteen recurrences observed (27.1%) over a six-month period. In the second group, a complete response was obtained in 33 patients (89.2%), and recurrence was observed in nine patients (24.3%). Photodynamic therapy and cryotherapy appear to be comparative methods of treatment that may both serve as alternatives for the traditional surgical treatment of oral leukoplakia. The advantages of PDT are connected with minimally invasive and localized character of the treatment and with not damage of collagenous tissue structures, therefore normal cells will repopulate these arrangements. PDT is more convenient for patients, less painful, and more esthetic. Copyright © 2011 Elsevier B.V. All rights reserved.

Photodynamic therapy in treatment of severe oral lichen planus.

PubMed

Rabinovich, O F; Rabinovich, I M; Guseva, A V

2016-01-01

The aim of the study was to elaborate the rationale for the application of photodynamic therapy in complex treatment of patient with severe oral lichen planus. Complex clinical and laboratory examination and treatment was performed in 54 patients divided on 3 groups. Diagnosis of oral lichen planus was based on clinical, histological and immunohistochemical features. Group 1 received standard treatment, in the second group photodynamic therapy was conducted in addition to conventional treatment, patients in the third group received only photodynamic therapy. The study results proved photodynamic therapy to be useful tool in complex treatment of severe oral lichen planus.

A Strategy Using Photodynamic Therapy and Clofibric Acid to Treat Peritoneal Dissemination of Ovarian Cancer.

PubMed

Yokoyama, Yoshihito; Shigeto, Tatsuhiko; Miura, Rie; Kobayashi, Asami; Mizunuma, Makito; Yamauchi, Aisa; Futagami, Masayuki; Mizunuma, Hideki

2016-01-01

The current study examined the effectiveness of concurrent therapy using photodynamic therapy (PDT) and clofibric acid (CA) to treat peritoneal carcinomatosis resulting from ovarian cancer. Nude rats were used to create a model of peritoneal carcinomatosis resulting from ovarian cancer and the effectiveness of PDT with 5-aminolevulinic acid methyl ester hydrochloride (methyl-ALA-PDT) was determined. The survival time of rats receiving that therapy was compared to the survival time of a control group. Rats with peritoneal carcinomatosis resulting from ovarian cancer were divided into 3 groups: a group that received debulking surgery (DS) alone, a group that received DS+methyl-ALA-PDT, and a group that received DS+methyl-ALA-PDT+CA. The survival time of the 3 groups was compared. Protoporphyrin, a metabolite of methyl-ALA, produces a photochemical action when activated by light. The level of protoporphyrin (the concentration) that reached organs in the abdomen was measured with HPLC. Rats receiving methyl- ALA-PDT had a significantly longer survival time compared to the controls. Rats with peritoneal carcinomatosis that received DS+methyl-ALA-PDT+CA had a significantly longer survival time compared to the rats that received DS alone. Some of the rats that received concurrent therapy survived for a prolonged period. Protoporphyrin was highly concentrated in peritoneal metastases, but only small amounts reached major organs in the abdomen. PDT was not found to result in necrosis in the intestines. The results indicated that concurrent therapy consisting of PDT with methyl-ALA and CA is effective at treating peritoneal carcinomatosis resulting from ovarian cancer without damaging organs.

Photodynamic Cancer Therapy - Recent Advances

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abrahamse, Heidi

The basic principle of the photodynamic effect was discovered over a hundred years ago leading to the pioneering work on PDT in Europe. It was only during the 1980s, however, when 'photoradiation therapy' was investigated as a possible treatment modality for cancer. Photodynamic therapy (PDT) is a photochemotherapeutic process which requires the use of a photosensitizer (PS) that, upon entry into a cancer cell is targeted by laser irradiation to initiate a series of events that contribute to cell death. PSs are light-sensitive dyes activated by a light source at a specific wavelength and can be classified as first ormore » second generation PSs based on its origin and synthetic pathway. The principle of PS activation lies in a photochemical reaction resulting from excitation of the PS producing singlet oxygen which in turn reacts and damages cell organelles and biomolecules required for cell function and ultimately leading to cell destruction. Several first and second generation PSs have been studied in several different cancer types in the quest to optimize treatment. PSs including haematoporphyrin derivative (HpD), aminolevulinic acid (ALA), chlorins, bacteriochlorins, phthalocyanines, naphthalocyanines, pheophorbiedes and purpurins all require selective uptake and retention by cancer cells prior to activation by a light source and subsequent cell death induction. Photodynamic diagnosis (PDD) is based on the fluorescence effect exhibited by PSs upon irradiation and is often used concurrently with PDT to detect and locate tumours. Both laser and light emitting diodes (LED) have been used for PDT depending on the location of the tumour. Internal cancers more often require the use of laser light delivery using fibre optics as delivery system while external PDT often make use of LEDs. Normal cells have a lower uptake of the PS in comparison to tumour cells, however the acute cytotoxic effect of the compound on the recovery rate of normal cells is not known

Application of 1,2-diethyl-3-hydroxypyridin-4-one to enhance tissue selectivity for photodynamic therapy of the bladder

NASA Astrophysics Data System (ADS)

Chang, Shi-Chung; MacRobert, Alexander J.; Porter, John B.; Bown, Stephen G.

1995-03-01

Five-aminolaevulinic acid (ALA) induced protoporphyrin IX (PpIX) has proven to be a useful photosensitizer for photodynamic therapy (PDT). In living cells, the conversion of PpIX to photoinactive haem is catalyzed by ferrochelatase in the presence of tissue iron and inhibition of this final committed step results in increased accumulation of PpIX. The in vivo effect of a new iron chelator, 1,2-diethyl-3-hydroxypyridin-4-one (CP94), on the buildup of PpIX in different bladder layers was evaluated. In CP94 treated rats, 5 - 7 hours after intravesical instillation of ALA solution, the fluorescence intensity of PpIX in the urothelium was doubled whilst in the muscle layer it remained low at a similar level to those seen without the iron chelator. With CP94, further reduction of skin photosensitization is possible as a similar photodynamic effect on the bladder could be achieved at lower ALA concentration. The addition of CP94 seems an effective and convenient way to potentiate ALA induced PpIX tissue selectivity.

Long-term (6 and 12 months) follow-up of two prospective, randomized, controlled phase III trials of photodynamic therapy with BF-200 ALA and methyl aminolaevulinate for the treatment of actinic keratosis

PubMed Central

Dirschka, T; Radny, P; Dominicus, R; Mensing, H; Brüning, H; Jenne, L; Karl, L; Sebastian, M; Oster-Schmidt, C; Klövekorn, W; Reinhold, U; Tanner, M; Gröne, D; Deichmann, M; Simon, M; Hübinger, F; Hofbauer, G; Krähn-Senftleben, G; Borrosch, F; Reich, K; Berking, C; Wolf, P; Lehmann, P; Moers-Carpi, M; Hönigsmann, H; Wernicke-Panten, K; Hahn, S; Pabst, G; Voss, D; Foguet, M; Schmitz, B; Lübbert, H; Szeimies, R-M

2013-01-01

Background Two phase III trials of photodynamic therapy (PDT) with BF-200 ALA, a recently approved nanoemulsion formulation of 5-aminolaevulinic acid (ALA) demonstrated high clearance rates in mild-to-moderate actinic keratosis (AK). The comparison to a registered methyl aminolaevulinate (MAL) cream demonstrated significantly superior total patient clearance rates. Objectives To evaluate long-term efficacy and safety of PDT for AK 6 and 12 months after the last PDT with BF-200 ALA, MAL or placebo. Methods The follow-up phase (FUP) was performed with patients of two phase III studies. Both studies compared BF-200 ALA with placebo, one of the studies additionally with MAL. Overall recurrence rates and various subgroups (light source, lesion severity, lesion location, complete responders after first PDT) were assessed 6 and 12 months after the last PDT. Results Recurrence rates were similar for BF-200 ALA and MAL, with a tendency to lower recurrence rates for BF-200 ALA. The proportion of patients who were fully cleared during PDT and remained completely clear for at least 12 months after PDT were 47% for BF-200 ALA (both studies) and 36% for MAL treatment. The subgroup that was illuminated with narrow wavelength LED lamps reached 69% and 53% for BF-200 ALA (both studies, respectively) and 41% for MAL. No safety concerns were reported. Conclusions The FUP data confirmed the high efficacy and safety of PDT with BF-200 ALA. The slightly lower recurrence rates after BF-200 ALA treatment compared with MAL treatment enhanced the better treatment outcome due to the significantly superior efficacy. PMID:23252768

Photodynamic therapy for basal cell carcinoma.

PubMed

Fargnoli, Maria Concetta; Peris, Ketty

2015-11-01

Topical photodynamic therapy is an effective and safe noninvasive treatment for low-risk basal cell carcinoma, with the advantage of an excellent cosmetic outcome. Efficacy of photodynamic therapy in basal cell carcinoma is supported by substantial research and clinical trials. In this article, we review the procedure, indications and clinical evidences for the use of photodynamic therapy in the treatment of basal cell carcinoma.

Photodynamic therapy--aspects of pain management.

PubMed

Fink, Christine; Enk, Alexander; Gholam, Patrick

2015-01-01

Topical photodynamic therapy (PDT) is a highly effective and safe treatment method for actinic keratoses with an excellent cosmetic outcome and is commonly used for the therapy of large areas of photodamaged skin with multiple clinically manifest and subclinical lesions. However, the major drawback of photodynamic therapy is the pain experienced during the treatment that can be intense and sometimes even intolerable for patients, requiring interruption or termination of the process. Several strategies for controlling pain during photodynamic therapy have been studied but few effective methods are currently available. Therefore, this review puts the spotlight on predictors on pain intensity and aspects of pain management during photodynamic therapy. © 2014 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Study of false positives in 5-ALA induced photodynamic diagnosis of bladder carcinoma

NASA Astrophysics Data System (ADS)

Draga, Ronald O. P.; Grimbergen, Matthijs C. M.; Kok, Esther T.; Jonges, Trudy G. N.; Bosch, J. L. H. R.

2009-02-01

Photodynamic diagnosis (PDD) is a technique that enhances the detection of tumors during cystoscopy using a photosensitizer which accumulates primarily in cancerous cells and will fluoresce when illuminated by violetblue light. A disadvantage of PDD is the relatively low specificity. In this retrospective study we aimed to identify predictors for false positive findings in PDD. Factors such as gender, age, recent transurethral resection of bladder tumors (TURBT), previous intravesical therapy (IVT) and urinary tract infections (UTIs) were examined for association with the false positive rates in a multivariate analysis. Data of 366 procedures and 200 patients were collected. Patients were instilled with 5-aminolevulinic acid (5-ALA) intravesically and 1253 biopsies were taken from tumors and suspicious lesions. Female gender and TURBT are independent predictors of false positives in PDD. However, previous intravesical therapy with Bacille Calmette-Guérin is also an important predictor of false positives. The false positive rate decreases during the first 9-12 weeks after the latest TURBT and the latest intravesical chemotherapy. Although shortly after IVT and TURBT false positives increase, PDD improves the diagnostic sensitivity and results in more adequate treatment strategies in a significant number of patients.

Doxycycline potentiates antitumor effect of 5-aminolevulinic acid-mediated photodynamic therapy in malignant peripheral nerve sheath tumor cells

PubMed Central

Lee, Ming-Jen; Hung, Shih-Hsuan; Huang, Mu-Ching; Tsai, Tsuimin

2017-01-01

Neurofibromatosis type 1 (NF1) is one of the most common neurocutaneous disorders. Some NF1 patients develop benign large plexiform neurofibroma(s) at birth, which can then transform into a malignant peripheral nerve sheath tumor (MPNST). There is no curative treatment for this rapidly progressive and easily metastatic neurofibrosarcoma. Photodynamic therapy (PDT) has been developed as an anti-cancer treatment, and 5-aminolevulinic (ALA) mediated PDT (ALA-PDT) has been used to treat cutaneous skin and oral neoplasms. Doxycycline, a tetracycline derivative, can substantially reduce the tumor burden in human and animal models, in addition to its antimicrobial effects. The purpose of this study was to evaluate the effect and to investigate the mechanism of action of combined doxycycline and ALA-PDT treatment of MPNST cells. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the combination of ALA-PDT and doxycycline significantly reduce MPNST survival rate, compared to cells treated with each therapy alone. Isobologram analysis showed that the combined treatment had a synergistic effect. The increased cytotoxic activity could be seen by an increase in cellular protoporphyrin IX (PpIX) accumulation. Furthermore, we found that the higher retention of PpIX was mainly due to increasing ALA uptake, rather than activity changes of the enzymes porphobilinogen deaminase and ferrochelatase. The combined treatment inhibited tumor growth in different tumor cell lines, but not in normal human Schwann cells or fibroblasts. Similarly, a synergistic interaction was also found in cells treated with ALA-PDT combined with minocycline, but not tetracycline. In summary, doxycycline can potentiate the effect of ALA-PDT to kill tumor cells. This increased potency allows for a dose reduction of doxycycline and photodynamic radiation, reducing the occurrence of toxic side effects in vivo. PMID:28558025

Doxycycline potentiates antitumor effect of 5-aminolevulinic acid-mediated photodynamic therapy in malignant peripheral nerve sheath tumor cells.

PubMed

Lee, Ming-Jen; Hung, Shih-Hsuan; Huang, Mu-Ching; Tsai, Tsuimin; Chen, Chin-Tin

2017-01-01

Neurofibromatosis type 1 (NF1) is one of the most common neurocutaneous disorders. Some NF1 patients develop benign large plexiform neurofibroma(s) at birth, which can then transform into a malignant peripheral nerve sheath tumor (MPNST). There is no curative treatment for this rapidly progressive and easily metastatic neurofibrosarcoma. Photodynamic therapy (PDT) has been developed as an anti-cancer treatment, and 5-aminolevulinic (ALA) mediated PDT (ALA-PDT) has been used to treat cutaneous skin and oral neoplasms. Doxycycline, a tetracycline derivative, can substantially reduce the tumor burden in human and animal models, in addition to its antimicrobial effects. The purpose of this study was to evaluate the effect and to investigate the mechanism of action of combined doxycycline and ALA-PDT treatment of MPNST cells. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the combination of ALA-PDT and doxycycline significantly reduce MPNST survival rate, compared to cells treated with each therapy alone. Isobologram analysis showed that the combined treatment had a synergistic effect. The increased cytotoxic activity could be seen by an increase in cellular protoporphyrin IX (PpIX) accumulation. Furthermore, we found that the higher retention of PpIX was mainly due to increasing ALA uptake, rather than activity changes of the enzymes porphobilinogen deaminase and ferrochelatase. The combined treatment inhibited tumor growth in different tumor cell lines, but not in normal human Schwann cells or fibroblasts. Similarly, a synergistic interaction was also found in cells treated with ALA-PDT combined with minocycline, but not tetracycline. In summary, doxycycline can potentiate the effect of ALA-PDT to kill tumor cells. This increased potency allows for a dose reduction of doxycycline and photodynamic radiation, reducing the occurrence of toxic side effects in vivo.

Long-term (6 and 12 months) follow-up of two prospective, randomized, controlled phase III trials of photodynamic therapy with BF-200 ALA and methyl aminolaevulinate for the treatment of actinic keratosis.

PubMed

Dirschka, T; Radny, P; Dominicus, R; Mensing, H; Brüning, H; Jenne, L; Karl, L; Sebastian, M; Oster-Schmidt, C; Klövekorn, W; Reinhold, U; Tanner, M; Gröne, D; Deichmann, M; Simon, M; Hübinger, F; Hofbauer, G; Krähn-Senftleben, G; Borrosch, F; Reich, K; Berking, C; Wolf, P; Lehmann, P; Moers-Carpi, M; Hönigsmann, H; Wernicke-Panten, K; Hahn, S; Pabst, G; Voss, D; Foguet, M; Schmitz, B; Lübbert, H; Szeimies, R-M

2013-04-01

Two phase III trials of photodynamic therapy (PDT) with BF-200 ALA, a recently approved nanoemulsion formulation of 5-aminolaevulinic acid (ALA) demonstrated high clearance rates in mild-to-moderate actinic keratosis (AK). The comparison to a registered methyl aminolaevulinate (MAL) cream demonstrated significantly superior total patient clearance rates. To evaluate long-term efficacy and safety of PDT for AK 6 and 12 months after the last PDT with BF-200 ALA, MAL or placebo. The follow-up phase (FUP) was performed with patients of two phase III studies. Both studies compared BF-200 ALA with placebo, one of the studies additionally with MAL. Overall recurrence rates and various subgroups (light source, lesion severity, lesion location, complete responders after first PDT) were assessed 6 and 12 months after the last PDT. Recurrence rates were similar for BF-200 ALA and MAL, with a tendency to lower recurrence rates for BF-200 ALA. The proportion of patients who were fully cleared during PDT and remained completely clear for at least 12 months after PDT were 47% for BF-200 ALA (both studies) and 36% for MAL treatment. The subgroup that was illuminated with narrow wavelength LED lamps reached 69% and 53% for BF-200 ALA (both studies, respectively) and 41% for MAL. No safety concerns were reported. The FUP data confirmed the high efficacy and safety of PDT with BF-200 ALA. The slightly lower recurrence rates after BF-200 ALA treatment compared with MAL treatment enhanced the better treatment outcome due to the significantly superior efficacy. © 2012 Biofrontera Bioscience GmbH BJD © 2012 British Association of Dermatologists.

Topical photodynamic therapy of squamous cell carcinomas in a hairless mouse model

NASA Astrophysics Data System (ADS)

Wang, Hong-Wei; Lv, Ting; Li, Jing-Jing; Tu, Qingfeng; Huang, Zheng; Wang, Xiu-Li

2013-02-01

Objectives: To examine therapeutic effects of 5-aminolevulinate (ALA)-mediated photodynamic therapy (PDT) on UVB-induced cutaneous squamous cell carcinomas (SCCs) in a mouse model. Materials and methods: Cutaneous SCCs were established by UVB (280-320 nm) irradiation of hairless mice. In situ fluorescence measurement was used to monitor PpIX formation after the topical application of various concentrations of ALA cream to determine the optimal ALA dose. Therapeutic responses of SCCs to multiple sessions of ALA PDT were examined histologically and quantitatively. TUNEL staining was used to examine apoptosis caused by PDT. Results: After repeated exposure for 18 to 22 weeks (4-5 days/week), multiple nodular and verrucous hyperplasia lesions of various sizes developed at the exposed area. After four sessions of ALA PDT (8% ALA, 3 h incubation, 30 J/cm2 at 20 mW/cm2) a total of 84% of complete response was achieved for small SCCs (1-4 mm, thickness <2.5 mm). TUNEL staining showed that PDT-induced apoptotic cells were distributed evenly from the basal to stratum corneum layers. Conclusions: Topical ALA PDT can trigger apoptosis in SCCs, inhibit SCC growth, and reduce the size and number of tumors in the hairless mouse model. The true clinical value of ALA PDT for the treatment of cutaneous SCC deserves further investigation.

A retrospective review of pain control by a two-step irradiance schedule during topical ALA-photodynamic therapy of non-melanoma skin cancer.

PubMed

Zeitouni, Nathalie C; Paquette, Anne D; Housel, Joseph P; Shi, Yi; Wilding, Gregory E; Foster, Thomas H; Henderson, Barbara W

2013-02-01

Photodynamic therapy (PDT) with topical δ-aminolevulinic acid (ALA) of non-melanoma skin cancers is often associated with treatment-limiting pain. A previous study on basal cell carcinomas (BCCs) at Roswell Park Cancer Institute evaluated a two-step irradiance scheme as a means of minimizing pain, preserving outcomes, and limiting treatment time. We used an initial low irradiance until 90% of the protoporphyrin IX was photobleached, followed by a high irradiance interval until the prescribed fluence was delivered. Success of this pilot investigation motivated integration of the protocol into routine practice. Here, we present a retrospective review of recent clinical experience in a broad patient population. This was a retrospective review of an existing dermatology database. Fourteen caucasion patients-nine men and five women, ages 18-80, with a total of 51 superficial and 73 nodular BCCs, and three Bowen's disease lesions-were included. ALA was applied to each lesion for approximately 4 hours. Lesions received an initial irradiance of 30-50 mW/cm(2) for 20 J/cm(2) , followed by 150 mW/cm(2) for a total fluence of 200-300 J/cm(2) . Pain was assessed using a visual analog scale (VAS). Clinical outcome was determined at 6-12 months. Median VAS scores were 1.0 for both irradiances. Five of 127 lesions required pain control with 1% xylocaine. Pain was strongly influenced by lesion location but not by lesion type, number, or size. Complete responses were achieved in 84.1% of BCCs, which compares favorably with reported results for single ALA-PDT treatments. Two of three Bowen's disease lesions showed a complete response. Complete responses for nodular BCCs were 37%, which are also within the range of reported outcomes. A two-step irradiance protocol in ALA-PDT effectively minimizes pain, maintains excellent clinical outcomes in superficial lesions, and adds minimal treatment time. Copyright © 2013 Wiley Periodicals, Inc.

Topical photodynamic therapy with 5-ALA in the treatment of arsenic-induced skin tumors

NASA Astrophysics Data System (ADS)

Karrer, Sigrid; Szeimies, Rolf-Markus; Landthaler, Michael

1995-03-01

A case of a 62-year-old woman suffering from psoriasis who was treated orally with arsenic 25 years ago is reported. The cumulative dose of arsenic trioxide was 800 mg. Since 10 years ago arsenic keratoses, basal cell carcinomas, Bowen's disease and invasive squamous cell carcinomas mainly on her hands and feet have developed, skin changes were clearly a sequence of arsenic therapy. Control of disease was poor, her right little finger had to be amputated. Topical photodynamic therapy with 5-aminolevulinic acid was performed on her right hand. Clinical and histological examinations 6 months after treatment showed an excellent cosmetic result with no signs of tumor residue.

Monitoring blood flow responses during topical ALA-PDT

PubMed Central

Becker, Theresa L.; Paquette, Anne D.; Keymel, Kenneth R.; Henderson, Barbara W.; Sunar, Ulas

2011-01-01

Photodynamic therapy (PDT) using topical 5-aminolevulinic acid (ALA) is currently used as a clinical treatment for nonmelanoma skin cancers. In order to optimize PDT treatment, vascular disruption early in treatment must be identified and prevented. We present blood flow responses to topical ALA-PDT in a preclinical model and basal cell carcinoma patients assessed by diffuse correlation spectroscopy (DCS). Our results show that ALA-PDT induced early blood flow changes and these changes were irradiance dependent. It is clear that there exists considerable variation in the blood flow responses in patients from lesion to lesion. Monitoring blood flow parameter may be useful for assessing ALA-PDT response and planning. PMID:21326642

Diketopyrrolopyrrole-based carbon dots for photodynamic therapy.

PubMed

He, Haozhe; Zheng, Xiaohua; Liu, Shi; Zheng, Min; Xie, Zhigang; Wang, Yong; Yu, Meng; Shuai, Xintao

2018-06-01

The development of a simple and straightforward strategy to synthesize multifunctional carbon dots for photodynamic therapy (PDT) has been an emerging focus. In this work, diketopyrrolopyrrole-based fluorescent carbon dots (DPP CDs) were designed and synthesized through a facile one-pot hydrothermal method by using diketopyrrolopyrrole (DPP) and chitosan (CTS) as raw materials. DPP CDs not only maintained the ability of DPP to generate singlet oxygen (1O2) but also have excellent hydrophilic properties and outstanding biocompatibility. In vitro and in vivo experiments demonstrated that DPP CDs greatly inhibited the growth of tumor cells under laser irradiation (540 nm). This study highlights the potential of the rational design of CDs for efficient cancer therapy.

Photodynamic therapy of normal rat arteries after photosensitisation using disulphonated aluminium phthalocyanine and 5-aminolaevulinic acid.

PubMed Central

Grant, W. E.; Speight, P. M.; MacRobert, A. J.; Hopper, C.; Bown, S. G.

1994-01-01

Photodynamic therapy of cancer exposes adjacent arteries to the risk of injury and the possibility of haemorrhage and thrombosis. The nature of photodynamic injury to normal arteries has not been satisfactorily defined, and the ability of arteries to recover with time is unclear. To clarify these issues, we have investigated the effects of PDT on rat femoral arteries, using a second-generation photosensitiser, disulphonated aluminium phthalocyanine, and a new method of photosensitisation, using endogenous synthesis of protoporphyrin IX following systemic administration of 5-aminolaevulinic acid (ALA). Pharmacokinetic studies of sensitiser fluorescence were carried out to determine peak levels of sensitiser. Subsequently photodynamic therapy at times corresponding to maximal fluorescence was performed using two light doses, 100 and 250 J cm-2. The nature of injury sustained and recovery over a 6 month period was investigated. Three days following PDT, all vessels treated showed complete loss of endothelium, with death of all medial smooth muscle cells, leaving an acellular flaccid artery wall. No vascular occlusion, haemorrhage or thrombosis was found. A striking feature was the lack of inflammatory response in the vessel wall at any time studied. Re-endothelialisation occurred in all vessels by 2 weeks. The phthalocyanine group showed repopulation of the media with smooth muscle cells to be almost complete by 3 months. However, the ALA group failed to redevelop a muscular wall and remained dilated at 6 months. Luminal cross-sectional area of the ALA-treated group was significantly greater than both control and phthalocyanine groups at 6 months. All vessels remained patent. This study indicates that arteries exposed to PDT are not at risk of catastrophic haemorrhage or occlusion, a finding that is of significance for both the local treatment of tumours and the use of PDT as an intraoperative adjunct to surgery for the ablation of microscopic residual malignant

Fluorescence guided evaluation of photodynamic therapy as acne treatment

NASA Astrophysics Data System (ADS)

Ericson, Marica B.; Horfelt, Camilla; Cheng, Elaine; Larsson, Frida; Larko, Olle; Wennberg, Ann-Marie

2005-08-01

Photodynamic therapy (PDT) is an attractive alternative treatment for patients with acne because of its efficiency and few side effects. Propionibacterium acnes (P.acnes) are bacteria present in the skin, which produce endogenous porphyrins that act as photosensitisers. In addition, application of aminolaevulinic acid or its methyl ester (mALA) results in increased accumulation of porphyrins in the pilosebaceous units. This makes it possible to treat acne with PDT. This initial study investigates the possibility of fluorescence imaging as assessment tool in adjunct to PDT of patients with acne. Twenty-four patients with acne on the cheeks have been treated with PDT with and without mALA. Fluorescence images have been obtained before and after treatment. The clinical acne score was assessed as base line before PDT, and at every follow up visit. Additionally the amount of P.acnes was determined. The clinical evaluation showed a general improvement of acne, even though no difference between treatment with and without mALA was observed. By performing texture analysis and multivariate data analsysis on the fluorescence images, the extracted texture features were found to correlate with the corresponding clinical assessment (67%) and amount of P.acnes (72%). The analysis showed that features describing the highly fluorescent pores could be related to the clinical assessment. This result suggests that fluorescence imaging can be used as an objective assessment of acne, but further improvement of the technique is possible, for example by including colour images.

[Photodynamic therapy of urinary bladder cancer using a chlorin based photosensitizer].

PubMed

Iagudaev, D M; Martov, A G; Sorokatyĭ, A E; Geĭnits, A V

2006-01-01

Photodynamic therapy (PDT) is a modem, low-invasive method of urinary bladder (UB) cancer treatment. PDT can induce complete or partial destruction of the tumor, reduce recurrence rate, provide assistance to elderly patients with compromised somatic status who are not radically operable. A combined technique improves the results of photodynamic therapy in patients with surface and invasive UB cancer of stage T2 because photodynamic impact affects not only the tumor but also all UB mucosa by light fiber with cylindric diffusor introduced in a silicon balloon with water. This leads to tumor destruction and a recurrence rate decrease.

Photodynamic therapy in endodontics: a literature review.

PubMed

Trindade, Alessandra Cesar; De Figueiredo, José Antônio Poli; Steier, Liviu; Weber, João Batista Blessmann

2015-03-01

Recently, several in vitro and in vivo studies demonstrated promising results about the use of photodynamic therapy during root canal system disinfection. However, there is no consensus on a standard protocol for its incorporation during root canal treatment. The purpose of this study was to summarize the results of research on photodynamic therapy in endodontics published in peer-reviewed journals. A review of pertinent literature was conducted using the PubMed database, and data obtained were categorized into sections in terms of relevant topics. Studies conducted in recent years highlighted the antimicrobial potential of photodynamic therapy in endodontics. However, most of these studies were not able to confirm a significant improvement in root canal disinfection for photodynamic therapy as a substitute for current disinfection methods. Its indication as an excellent adjunct to conventional endodontic therapy is well documented, however. Data suggest the need for protocol adjustments or new photosensitizer formulations to enhance photodynamic therapy predictability in endodontics.

Single LED-based device to perform widefield fluorescence imaging and photodynamic therapy

NASA Astrophysics Data System (ADS)

Grecco, Clovis; Buzzá, Hilde H.; Stringasci, Mirian D.; Andrade, Cintia T.; Vollet-Filho, Jose D.; Pratavieira, Sebastião.; Zanchin, Anderson L.; Tuboy, Aparecida M.; Bagnato, Vanderlei S.

2015-06-01

Photodynamic therapy (PDT) is a treatment modality that can be indicated for several cancer types and pre-cancer lesions. One of the main applications of PDT is the treatment of superficial skin lesions such as basal cell carcinoma, Bowen's disease and actinic keratosis. Three elements are necessary in PDT, a photosensitizer (PS); light at specific wavelength to be absorbed by the PS, and molecular oxygen. A typical PS used for skin lesion is protoporphyrin IX (PpIX), which is an intrinsic PS; its production is stimulated by a pro-drug, such as 5-aminolevulinic acid (ALA). Before starting a treatment, it is very important to follow up the PpIX production (to ensure that enough PS was produced prior to a PDT application) and, during a PDT session, to monitor its photodegradation (as it is evidence of the photodynamic effect taking place). The aim of this paper is to present a unique device, LINCE (MMOptics - São Carlos, Brazil), that brings together two probes that can, respectively, allow for fluorescence imaging and work as a light source for PDT treatment. The fluorescence probe of the system is optically based on 400 nm LED (light emitting diodes) arrays that allow observing the fluorescence emission over 450 nm. The PDT illumination probe options are constituted of 630 nm LED arrays for small areas and, for large areas, of both 630 nm and 450 nm LED arrays. Joining both functions at the same device makes PDT treatment simpler, properly monitorable and, hence, more clinically feasible. LINCE has been used in almost 1000 PDT treatments of superficial skin lesions in Brazil, with 88.4% of clearance of superficial BCC.

Real-Time Dosimetry and Optimization of Prostate Photodynamic Therapy

DTIC Science & Technology

2006-09-01

photodynamic therapy in patients with prostate cancer,” IPA 9th World Congress of Photodynamic Medicine, (2003). 2. Zhu TC, Diana S, Dimofte A...photodynamic therapy,” IPA 9th World Congress of Photodynamic Medicine, (2003). 3. Zhu TC, Altschuler M, Xiao Y, Finlay J, Dimofte A, Hahn SM, “Light...Optimization of treatment plan using Cimmino algorithm in prostate photodynamic therapy,” IPA 10th World Congress of Photodynamic Medicine, Munich

Molecular beacon-based photodynamic therapy

NASA Astrophysics Data System (ADS)

Chen, Juan; Stefflova, Klara; Kim, Soungkyoo; Li, Hui; Marotta, Diane; Chance, Britton; Glickson, Jerry D.; Zheng, Gang

2005-01-01

A new concept for photodynamic therapy (PDT) has been developed based on incorporating a photosensitizer (PS) and a singlet oxygen (1O2) quenching/scavenging molecule (Q) onto a disease-targeting carrier, such that the PS becomes activatable by light only when targeting has occurred. This has the potential to give very high disease specificity in PDT treatment. The first model compound designed using this concept was synthesized containing a pyropheophorbide as the PS and a carotenoid as the 1O2 quencher. These were kept in close proximity by the self-folding of a caspase-3 specific peptide sequence. Upon caspase-3-induced cleavage, the 1O2 production increase has been validated by direct 1O2 luminescence and lifetime measurements, providing proof-of-concept of this 'PDT beacon.'

Comparison of Blue and White Lamp Light with Sunlight for Daylight-Mediated, 5-ALA Photodynamic Therapy, in vivo.

PubMed

Marra, Kayla; LaRochelle, Ethan P; Chapman, M Shane; Hoopes, P Jack; Lukovits, Karina; Maytin, Edward V; Hasan, Tayyaba; Pogue, Brian W

2018-04-16

Daylight-mediated photodynamic therapy (d-PDT) as a treatment for actinic keratosis (AK) is an increasingly common technique due to a significant reduction in pain, leading to better patient tolerability. While past studies have looked at different light sources and delivery methods, this study strives to provide equivalent PpIX-weighted light doses with the hypothesis that artificial light sources could be equally as effective as natural sunlight if their PpIX-weighted fluences were equalized. Normal mouse skin was used as the model to compare blue LED light, metal halide white light and natural sunlight, with minimal incubation time between topical ALA application and the onset of light delivery. A total PpIX-weighted fluence of 20 J eff cm -2 was delivered over 2 h, and the efficacy of response was quantified using three acute bioassays for PDT damage: PpIX photobleaching, Stat3 crosslinking and quantitative histopathology. These bioassays indicated blue light was slightly inferior to both sunlight and white light, but that the latter two were not significantly different. The results suggest that metal halide white light could be a reasonable alternative to daylight PDT, which should allow a more controlled treatment that is independent of weather and yet should have similar response rates with limited pain during treatment. © 2018 The American Society of Photobiology.

Topical versus systemic 5-aminolevulinic acid administration for photodynamic therapy of the colon in B10.RBP mice

NASA Astrophysics Data System (ADS)

Gil, Maciej; Woszczynski, Marek; Regula, Jaroslaw; MacRobert, Alexander J.; Butruk, Eugeniusz; Bown, Stephen G.

1999-07-01

5-aminolevulinic acid (5-ALA) is an interesting photosensitizing substance for photodynamic therapy (PDT), successfully applied topically for urological malignancy. In gastroenterology it has proven efficacy for treatment of some GI neoplasms after systemic administration. This study was aimed at investigating the possibility of topical 5-ALA administration also for the PDT of gut cancer in a mice model. 5-ALA solution at different concentrations (5%, 1.5%, and 0.5%) was instilled in the colon of mice, which was later removed and examined by fluorescence microscopy. The results of fluorescence studies were compared with those obtained in a control group treated with 5-ALA given systematically. Satisfactory epithelial fluorescence levels and good selectivity between gut layers were obtained after intracolonic 5-ALA instillation. However, mean fluorescence intensity was higher after systemic drug applications. Our results suggest that 5-ALA may probably be used topically for the PDT of some gut neoplasms.

[Application of photodynamic therapy in dentistry – literature review].

PubMed

Oruba, Zuzanna; Chomyszyn-Gajewska, Maria

Photodynamic therapy (PDT) is based on the principle that the target cells are destroyed by means of toxic reactive oxygen species generated upon the interaction of a photosensitizer, light and oxygen. This method is nowadays widely applied in various branches of medicine, mainly in oncology and dermatology. It is also applied in dentistry in the treatment of oral potentially malignant disorders (like lichen planus or leukoplakia) and infectious conditions (periodontitis, herpetic cheilitis, root canal disinfection). The application of the photodynamic therapy in the abovementioned indications is worth attention, as the method is noninvasive, painless, and the results of the published studies seem promising. The present article aims at presenting the principle of the photodynamic therapy and, based on the literature, the possibilities and results of its application in dentistry.

Photodynamic Therapy Combined with Terbinafine Against Chromoblastomycosis and the Effect of PDT on Fonsecaea monophora In Vitro

PubMed Central

Hu, Yongxuan; Huang, Xiaowen; Lu, Sha; Hamblin, Michael R.; Mylonakis, Eleftherios; Zhang, Junmin

2014-01-01

Chromoblastomycosis, a chronic fungal infection of skin and subcutaneous tissue caused by dematiaceous fungi, is associated with low cure and high relapse rates. Among all factors affecting clinical outcome, etiological agents have an important position. In southern China, Fonsecaea pedrosoi and Fonsecaea monophora are main causative agents causing Chromoblastomycosis. We treated one case of chromoblastomycosis by photodynamic therapy (PDT) of 5-aminolevulinic acid (ALA) irradiation combined with terbinafine 250 mg a day. The lesions were improved after two sessions of ALA-PDT treatment, each including nine times, at an interval of 1 week, combined with terbinafine 250 mg/day oral, and clinical improvement could be observed. In the following study, based on the clinical treatment, the effect of PDT and antifungal drugs on this isolate was detected in vitro. It showed sensitivity to terbinafine, itraconazole or voriconazole, and PDT inhibited the growth. Both the clinic and experiments in vitro confirm the good outcome of ALA-PDT applied in the inhibition of F. monophora. It demonstrated that combination of antifungal drugs with ALA-PDT arises as a promising alternative method for the treatment of these refractory cases of chromoblastomycosis. PMID:25366276

A new therapeutic proposal for inoperable osteosarcoma: Photodynamic therapy.

PubMed

de Miguel, Guilherme Chohfi; Abrantes, Ana Margarida; Laranjo, Mafalda; Grizotto, Ana Yoshie Kitagawa; Camporeze, Bruno; Pereira, José Aires; Brites, Gonçalo; Serra, Arménio; Pineiro, Marta; Rocha-Gonsalves, António; Botelho, Maria Filomena; Priolli, Denise Gonçalves

2018-03-01

Osteosarcoma, a malignant tumor characterized by bone or osteoid formation, is the second most common primary bone neoplasm. Clinical symptoms include local and surrounding pain, unrelieved by rest or anesthesia. Osteosarcoma has a poor chemotherapeutic response with prognosis dependent on complete tumor excision. Therefore, for inoperable osteosarcoma new therapeutic strategies are needed. The present study aimed to develop murine models of cranial and vertebral osteosarcoma that facilitate simple clinical monitoring and real-time imaging to evaluate the outcome of photodynamic therapy based on a previously developed photosensitizer. Balb/c nude mice were divided into two groups: the cranial and vertebral osteosarcoma groups. Each group was further subdivided into the photodynamic therapy-treated and untreated groups. Images were obtained by scintigraphy with 99m Tc-MIBI and radiography. Tumor growth, necrotic area, osteoid matrix area, and inflammatory infiltration were analyzed. Cranial and vertebral tumors could be macroscopically observed and measured. Radiographic and scintigraphic images showed tumor cells present at the inoculation sites. After photodynamic therapy, scintigraphy showed lower tumoral radiopharmaceutical uptake, which correlated histologically with increased necrosis. Osteoid matrix volume increased, and tumor size decreased in all photodynamic therapy-treated animals. Cranial and vertebral osteosarcoma models in athymic mice are feasible and facilitate in vivo monitoring for the development of new therapies. Photodynamic therapy is a potential antitumoral treatment for surgically inoperable osteosarcoma. Copyright © 2017 Elsevier B.V. All rights reserved.

Treatment of actinic cheilitis by photodynamic therapy with 5-aminolevulinic acid and blue light activation.

PubMed

Zaiac, Martin; Clement, Annabelle

2011-11-01

Actinic cheilitis (AC), a common disorder of the lower lip, should be treated early to prevent progression to invasive squamous cell carcinoma. This study evaluated the safety and efficacy of photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) activated by blue light for the treatment of AC. Fifteen patients with clinically evident or biopsy-proven AC received two treatments with ALA PDT with blue light activation. Treatments were spaced three to five weeks apart. Most patients achieved 65% to 75% clearance three to five weeks after the first treatment and all achieved more than 75% clearance one month after the second treatment. Three patients achieved complete clearance. Pain and burning during irradiation were absent or mild. All patients said they would repeat the procedure. ALA PDT with 417 nm blue light is a promising option for the treatment of AC of the lower lip.

[Photodynamic therapy for actinic cheilitis].

PubMed

Castaño, E; Comunión, A; Arias, D; Miñano, R; Romero, A; Borbujo, J

2009-12-01

Actinic cheilitis is a subtype of actinic keratosis that mainly affects the lower lip and has a higher risk of malignant transformation. Its location on the labial mucosa influences the therapeutic approach. Vermilionectomy requires local or general anesthetic and is associated with a risk of an unsightly scar, and the treatment with 5-fluorouracil or imiquimod lasts for several weeks and the inflammatory reaction can be very intense. A number of authors have used photodynamic therapy as an alternative to the usual treatments. We present 3 patients with histologically confirmed actinic cheilitis treated using photodynamic therapy with methyl aminolevulinic acid as the photosensitizer and red light at 630 nm. The clinical response was good, with no recurrences after 3 to 6 months of follow-up. Our experience supports the use of photodynamic therapy as a good alternative for the treatment of actinic cheilitis.

Photodynamic therapy of diseased bone

NASA Astrophysics Data System (ADS)

Bisland, Stuart K.; Yee, Albert; Siewerdsen, Jeffery; Wilson, Brian C.; Burch, Shane

2005-08-01

Objective: Photodynamic therapy (PDT) defines the oxygen-dependent reaction that occurs upon light-mediated activation of a photosensitizing compound, culminating in the generation of cytotoxic, reactive oxygen species, predominantly, singlet oxygen. We are investigating PDT treatment of diseased bone. Methods: Using a rat model of human breast cancer (MT-1)-derived bone metastasis we confirmed the efficacy of benzoporphyrin-derivative monoacid (BPD-MA)-PDT for treating metastatic lesions within vertebrae or long bones. Results: Light administration (150 J) 15 mins after BPDMA (2.5 mg/Kg, i.v.) into the lumbar (L3) vertebra of rats resulted in complete ablation of the tumour and surrounding bone marrow 48 hrs post-PDT without paralysis. Porcine vertebrae provided a model comparable to that of human for light propagation (at 150 J/cm) and PDT response (BPD-MA; 6 mg/m2, i.v.) in non-tumour vertebrae. Precise fibre placement was afforded by 3-D cone beam computed tomography. Average penetration depth of light was 0.16 +/- 0.04 cm, however, the necrotic/non-necrotic interface extended 0.6 cm out from the treatment fiber with an average incident fluence rate of 4.3 mW/cm2. Non-necrotic tissue damage was evident 2 cm out from the treatment fiber. Current studies involving BPD-MA-PDT treatment of primary osteosarcomas in the forelimbs of dogs are very promising. Magnetic resonance imaging 24 hr post treatment reveal well circumscribed margins of treatment that encompass the entire 3-4 cm lesion. Finally, we are also interested in using 5-aminolevulinic acid (ALA) mediated PDT to treat osteomyelitis. Response to therapy was monitored as changes in bioluminescence signal of staphylococcus aureus (SA)-derived biofilms grown onto 0.5 cm lengths of wire and subjected to ALA-PDT either in vitro or in vivo upon implant into the intramedullary space of rat tibia. Transcutaneous delivery of PDT (75 J/cm2) effectively eradicated SAbiofilms within bone. Conclusions: Results support

Hyperbaric oxygen therapy augments the photodynamic action of methylene blue against bacteria in vitro

NASA Astrophysics Data System (ADS)

Bisland, S. K.; Dadani, F. N.; Chien, C.; Wilson, B. C.

2007-02-01

Photodynamic therapy (PDT) entails the combination of photosensitizer and light to generate cytotoxic molecules that derive from molecular oxygen (O II). The presence of sufficient O II within the target tissues is critical to the efficiency of PDT. This study investigates the use of hyperbaric oxygen therapy in combination with PDT (HOTPDT) to augment the photodynamic action of methylene blue (MB) or 5-aminolevulinic acid (ALA) against gram positive and gram negative bacterial strains in vitro. Staphylococcus aureus or Pseudomonas aeruginosa were grown in trypticase soy broth as planktonic cultures (~10 8/mL) or as established biofilms in 48 well plates (3 days old) at 32°C. Dark toxicity and PDT response in the presence or absence of HOT (2 atmospheres, 100% O II for 30, 60 or 120 min) was established for both MB (0-0.1 mM) and ALA (0- 1 mM) for a range of incubation times. The number of surviving colonies (CFU/mL) was plotted for each treatment groups. Light treatments (5, 10, 20 or 30 J/cm2) were conducted using an array of halogen bulbs with a red filter providing 90% transmittance over 600-800 nm at 21 mW/cm2. HOT increased the dark toxicity of MB (30 min, 0.1 mM) from < 0.2 log cell kill to 0.5 log cell kill. Dark toxicity of ALA (4 hr, 1 mM) was negligible and did not increase with HOT. For non-dark toxic concentrations of MB or ALA, (0.05 mM and 1 mM respectively) HOT-PDT enhanced the antimicrobial effect of MB against Staphylococcus aureus in culture by >1 and >2 logs of cell kill (CFU/mL) at 5 and 10 J/cm2 light dose respectively as compared to PDT alone. HOT-PDT also increased the anti-microbial effects of MB against Staphylococcus aureus biofilms compared to PDT, albeit less so (> 2 logs) following 10 J/cm2 light dose. Anti-microbial effects of PDT using ALA were not significant for either strain with or without HOT. These data suggest that HOTPDT may be useful for improving the PDT treatment of bacterial infections.

Recent advances in the prevention and treatment of skin cancer using photodynamic therapy

PubMed Central

Zhao, Baozhong; He, Yu-Ying

2011-01-01

Photodynamic therapy (PDT) is a noninvasive procedure that involves a photosensitizing drug and its subsequent activation by light to produce reactive oxygen species that specifically destroy target cells. Recently, PDT has been widely used in treating non-melanoma skin malignancies, the most common cancer in the USA, with superior cosmetic outcomes compared with conventional therapies. The topical ‘photosensitizers’ commonly used are 5-aminolevulinic acid (ALA) and its esterified derivative methyl 5-aminolevulinate, which are precursors of the endogenous photosensitizer protoporphyrin IX. After treatment with ALA or methyl 5-aminolevulinate, protoporphyrin IX preferentially accumulates in the lesion area of various skin diseases, which allows not only PDT treatment but also fluorescence diagnosis with ALA-induced porphyrins. Susceptible lesions include various forms of non-melanoma skin cancer such as actinic keratosis, basal cell carcinoma and squamous cell carcinoma. The most recent and promising developments in PDT include the discovery of new photosensitizers, the exploitation of new drug delivery systems and the combination of other modalities, which will all contribute to increasing PDT therapeutic efficacy and improving outcome. This article summarizes the main principles of PDT and its current clinical use in the management of non-melanoma skin cancers, as well as recent developments and possible future research directions. PMID:21080805

Photodynamic therapy of urethral condylomata acuminata using topically 5-aminolevulinic acid

NASA Astrophysics Data System (ADS)

Wang, Xiuli; Wang, Hongwei; Wang, Haishan; Xu, Shizheng; Liao, Kanghuang; Hillemanns, Peter

2005-07-01

Background Electrocoagulation and laser evaporation for urethral condylomata acuminata have high recurrence rates and can be associated with urethral malformations. Objective To investigate the effect of photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) on urethral condylomata acuminata and to examine the histological changes in lesions of condylomata acuminata after ALA-PDT. Methods One hundred and sixty-four urethral condylomata patients were given topical ALA followed by intraurethral PDT through a cylindrical fiber. Among the cases, 16 penile and vulval condylomatous lesions in 11 patients were treated with topical ALA-PDT at same time. After the treatment, biopsy specimens were collected from the 16 penile and vulval lesions. The histological changes were then evaluated by light microscope and electron microscope. Results The complete response rate for urethral condylomata by topical ALA-PDT was 95.12% and the recurrence rate was 5.13% after 6 to 24 months follow-up. Keratinocytes in middle and upper layers of the epidermis with marked vacuolation and some necrocytosis were detected one and three hours after PDT. Necrosis in all layers of the epidermis was noted five hours after PDT by microscopy. In electron microscopy of kerationcytes, distinct ultrastructural abnormalities of mitochondrion, endoplasmic reticulum and membrane damage were observed. Apoptotic bodies were detected three hours after PDT and a large number of the keratinocytes exhibited necrosis five hours after PDT by electron microscope. Conclusions Results suggests that topical ALA-PDT is a simple, effective, relatively safe, less recurrent and comparatively well tolerated treatment for urethral condylomata acuminata. The mechanisms might be that ALA-PDT could trigger apoptotic process and necrosis in the HPV infected keratinocytes. Key words:

ABCG2 transporter inhibitor restores the sensitivity of triple negative breast cancer cells to aminolevulinic acid-mediated photodynamic therapy.

PubMed

Palasuberniam, Pratheeba; Yang, Xue; Kraus, Daniel; Jones, Patrick; Myers, Kenneth A; Chen, Bin

2015-08-18

Photosensitizer protoporphyrin IX (PpIX) fluorescence, intracellular localization and cell response to photodynamic therapy (PDT) were analyzed in MCF10A normal breast epithelial cells and a panel of human breast cancer cells including estrogen receptor (ER) positive, human epidermal growth factor receptor 2 (HER2) positive and triple negative breast cancer (TNBC) cells after treatment with PpIX precursor aminolevulinic acid (ALA). Although PpIX fluorescence was heterogeneous in different cells, TNBC cells showed significantly lower PpIX level than MCF10A and ER- or HER2-positive cells. PpIX fluorescence in TNBC cells also had much less mitochondrial localization than other cells. There was an inverse correlation between PpIX fluorescence and cell viability after PDT. Breast cancer cells with the highest PpIX fluorescence were the most sensitive to ALA-PDT and TNBC cells with the lowest PpIX level were resistant to PDT. Treatment of TNBC cells with ABCG2 transporter inhibitor Ko143 significantly increased ALA-PpIX fluorescence, enhanced PpIX mitochondrial accumulation and sensitized cancer cells to ALA-PDT. Ko143 treatment had little effect on PpIX production and ALA-PDT in normal and ER- or HER2-positive cells. These results demonstrate that enhanced ABCG2 activity renders TNBC cell resistance to ALA-PDT and inhibiting ABCG2 transporter is a promising approach for targeting TNBC with ALA-based modality.

Comparison microbial killing efficacy between sonodynamic therapy and photodynamic therapy

NASA Astrophysics Data System (ADS)

Drantantiyas, Nike Dwi Grevika; Astuti, Suryani Dyah; Nasution, Aulia M. T.

2016-11-01

Biofilm is a way used by bacteria to survive from their environmental conditions by forming colony of bacteria. Specific characteristic in biofilm formation is the availability of matrix layer, known as extracellular polymer substance. Treatment using antibiotics may lead bacteria to be to resistant. Other treatments to reduce microbial, like biofilm, can be performed by using photodynamic therapy. Successful of this kind of therapy is induced by penetration of light and photosensitizer into target cells. The sonodynamic therapy offers greater penetrating capability into tissues. This research aimed to use sonodynamic therapy in reducing biofilm. Moreover, it compares also the killing efficacy of photodynamic therapy, sonodynamic therapy, and the combination of both therapeutic schemes (known as sono-photodynamic) to achieve higher microbial killing efficacy. Samples used are Staphylococcus aureus biofilm. Treatments were divided into 4 groups, i.e. group under ultrasound treatment with variation of 5 power levels, group of light treatment with exposure of 75s, group of combined ultrasound-light with variation of ultrasound power levels, and group of combined lightultrasound with variation of ultrasound power levels. Results obtained for each treatment, expressed in % efficacy of log CFU/mL, showed that the treatment of photo-sonodynamic provides greater killing efficacy in comparison to either sonodynamic and sono-photodynamic. The photo-sonodynamic shows also greater efficacy to photodynamic. So combination of light-ultrasound (photo-sonodynamic) can effectively kill microbial biofilm. The combined therapy will provide even better efficacy using exogenous photosensitizer.

ALA-PDT mediated DC vaccine for skin squamous cell carcinoma

NASA Astrophysics Data System (ADS)

Ji, Jie; Fan, Zhixia; Zhou, Feifan; Wang, Xiaojie; Shi, Lei; Zhang, Haiyan; Wang, Peiru; Yang, Degang; Zhang, Linglin; Wang, Xiuli; Chen, Wei R.

2015-03-01

Dendritic cell (DC) based vaccine has emerged as a promising immunotherapy for cancers. However, most DC vaccines so far have only achieved limited success in cancer treatment. Photodynamic therapy (PDT), an established cancer treatment strategy, can cause immunogenic apoptosis to induce an effective antitumor immune response. In this study, we developed a DC-based cancer vaccine using immunogenic apoptotic tumor cells induced by 5-aminolevulinic acid (ALA) mediated PDT. The maturation of DCs induced by PDT-treated apoptotic cells was evaluated. The anti-tumor immunity of ALA-PDT-DC vaccine was tested with mouse model. We observed the maturations of DCs potentiated by ALA-PDT treated tumor cells, including phenotypic maturation (upregulation of surface expression of MHC-II, DC80, and CD86), and functional maturation (enhanced capability to secret INF-Υ and IL-12). ALA-PDT-DC vaccine mediated by apoptotic cells provided protection against tumor in mice, far stronger than that of DC vaccine obtained from freeze/thaw treated tumor cells. Our results indicate that immunogenic apoptotic tumor cells can be more effective in enhancing DC-based cancer vaccine, which could improve the clinical application of PDT- DC vaccines.

Spectral matching technology for light-emitting diode-based jaundice photodynamic therapy device

NASA Astrophysics Data System (ADS)

Gan, Ru-ting; Guo, Zhen-ning; Lin, Jie-ben

2015-02-01

The objective of this paper is to obtain the spectrum of light-emitting diode (LED)-based jaundice photodynamic therapy device (JPTD), the bilirubin absorption spectrum in vivo was regarded as target spectrum. According to the spectral constructing theory, a simple genetic algorithm as the spectral matching algorithm was first proposed in this study. The optimal combination ratios of LEDs were obtained, and the required LEDs number was then calculated. Meanwhile, the algorithm was compared with the existing spectral matching algorithms. The results show that this algorithm runs faster with higher efficiency, the switching time consumed is 2.06 s, and the fitting spectrum is very similar to the target spectrum with 98.15% matching degree. Thus, blue LED-based JPTD can replace traditional blue fluorescent tube, the spectral matching technology that has been put forward can be applied to the light source spectral matching for jaundice photodynamic therapy and other medical phototherapy.

Topical photodynamic therapy with porphyrin precursors--assessment of treatment-associated pain in a retrospective study.

PubMed

Steinbauer, Julia Maria; Schreml, Stephan; Babilas, Philipp; Zeman, Florian; Karrer, Sigrid; Landthaler, Michael; Szeimies, Rolf-Markus

2009-08-01

Photodynamic therapy (PDT) with aminolevulinic acid (ALA) or methyl aminolevulinate (MAL) is an approved modality for the non-invasive treatment of actinic keratoses (AK) and basal cell carcinoma (BCC) offering excellent cosmetic outcome. However, pain during and after illumination is the most frequent and limiting side effect. The aim of this study was to precisely assess how reported pain during PDT is influenced by sex, age, treatment site, disease (AK/BCC) as well as the photosensitizer used. 467 lesions consisting of AK (primary treatments: n=158; follow-up: n=47) or BCC (primary treatments: n=138; follow-up: 124) were treated by ALA- or MAL-PDT using metal halide lamps (580-750 nm). Pain was assessed during illumination using a continuous visual analogue scale (VAS). Factors predictive for higher pain levels during PDT are treatment of the head, treating AK and using ALA. The observed results may improve patient management and predict which level of pain to expect, and what kind of pain relief to prepare.

5-aminolevulinic acid-mediated photodynamic therapy and its strain-dependent combined effect with antibiotics on Staphylococcus aureus biofilm.

PubMed

Zhang, Qing-Zhao; Zhao, Ke-Qing; Wu, Yang; Li, Xian-Hui; Yang, Chen; Guo, Li-Min; Liu, Chun-Hong; Qu, Di; Zheng, Chun-Quan

2017-01-01

Staphylococcus aureus (S. aureus) is hard to be eradicated, not only due to the emergence of antibiotic resistant strains but also because of its ability to form biofilm. Antibiotics are the major approach to treating biofilm infections, but their effects are unsatisfactory. One of the potential alternative treatments for controlling biofilm infections is photodynamic therapy (PDT), which requires the administration of photosensitizer, followed by light activation. 5-aminolevulinic acid (ALA), a natural photosensitizer prodrug, presents favorable characteristics, such as easy penetration and rapid clearance. These advantages enable ALA-based PDT (ALA-PDT) to be well-tolerated by patients and it can be repeatedly applied without cumulative toxicity or serious side effects. ALA-PDT has been proven to be an effective treatment for multidrug resistant pathogens; however, the study of its effect on S. aureus biofilm is limited. Here, we established our PDT system based on the utilization of ALA and a light-emitting diode, and we tested the effect of ALA-PDT on S. aureus biofilm as well as the combined effect of ALA-PDT and antibiotics on S. aureus biofilm. Our results showed that ALA-PDT has a strong antibacterial effect on S. aureus biofilm, which was confirmed by the confocal laser scanning microscope. We also found that lethal photosensitization occurred predominantly in the upper layer of the biofilm, while the residual live bacteria were located in the lower layer of the biofilm. In addition, the improved bactericidal effect was observed in the combined treatment group but in a strain-dependent manner. Our results suggest that ALA-PDT is a potential alternative approach for future clinical use to treat S. aureus biofilm-associated infections, and some patients may benefit from the combined treatment of ALA-PDT and antibiotics, but drug sensitivity testing should be performed in advance.

Nanotechnology-Based Drug Delivery Systems for Photodynamic Therapy of Cancer: A Review.

PubMed

Calixto, Giovana Maria Fioramonti; Bernegossi, Jéssica; de Freitas, Laura Marise; Fontana, Carla Raquel; Chorilli, Marlus

2016-03-11

Photodynamic therapy (PDT) is a promising alternative approach for improved cancer treatment. In PDT, a photosensitizer (PS) is administered that can be activated by light of a specific wavelength, which causes selective damage to the tumor and its surrounding vasculature. The success of PDT is limited by the difficulty in administering photosensitizers (PSs) with low water solubility, which compromises the clinical use of several molecules. Incorporation of PSs in nanostructured drug delivery systems, such as polymeric nanoparticles (PNPs), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), gold nanoparticles (AuNPs), hydrogels, liposomes, liquid crystals, dendrimers, and cyclodextrin is a potential strategy to overcome this difficulty. Additionally, nanotechnology-based drug delivery systems may improve the transcytosis of a PS across epithelial and endothelial barriers and afford the simultaneous co-delivery of two or more drugs. Based on this, the application of nanotechnology in medicine may offer numerous exciting possibilities in cancer treatment and improve the efficacy of available therapeutics. Therefore, the aim of this paper is to review nanotechnology-based drug delivery systems for photodynamic therapy of cancer.

[Experimental study on the impact of photodynamic therapy on the normal vocal cord injury].

PubMed

Liu, Haiyan; Huang, Yongwang; Wang, Shanshan; Li, Yingxin; Yin, Huijuan; Gao, Xiaowei

2015-12-01

To investigate the reactive characteristics of normal vocal cord tissues to photodynamic therapy (PDT) and the damage effects of different concentration of photosensitizer and different light on normal rabbit vocal cord. Making the preliminary research of PDT in clinical treatment of chronic inflammation of the vocal cords and precancerous lesions. Twenty-five healthy Japanese big ear experimental rabbits were randomly divided into 5 groups: low work rate low dose group A (100 mW, 10%5-ALA), high work rate low dose group B (200 mW, 10%5-ALA), high work rate high dose group C (200 mW, 20%5-ALA), low work rate high dose group D (100 mW, 20%5-ALA) and normal control group E. The issue damage and wound recovery were observed in 1 d, 3 d, 7 d, 14 d, 28 d after intervention. A severe inflammation reaction was observed in group A, B, C, D after intervened with PDT compared to normal group. The reaction of group A was lighter, and the reaction of group C was the most serious. The content of collagenous fiber, hyaluronic acid and fibronectin in vocal fold lamina layer was significantly higher than that in normal group (P<0.05). Different degrees of fiber proliferation were observed in all groups. The content of each component of vocal fold lamina layer tended to be normal slightly higher level in 28 d. Observation by electron microscope showed that there were no significant differences in A, B, C, D, E in 28 d after intervention. Recoverable damage repair process can be detected in rabbit vocal after intervened with PDT, which began in 7 d and basically completed in 28 d. In a certain concentration (10%-20%) and dose range (100-200 mW). The higher of photodynamic dose, the more serious of the damage. And the damage was basically reversible.

Fluorescence image-guided photodynamic therapy of cancer cells using a scanning fiber endoscope

NASA Astrophysics Data System (ADS)

Woldetensae, Mikias H.; Kirshenbaum, Mark R.; Kramer, Greg M.; Zhang, Liang; Seibel, Eric J.

2013-03-01

A scanning fiber endoscope (SFE) and the cancer biomarker 5-aminolevulinic acid (5-ALA) were used to fluorescently detect and destroy superficial cancerous lesions, while experimenting with different dosimetry levels for concurrent or sequential imaging and laser therapy. The 1.6-mm diameter SFE was used to fluorescently image a confluent monolayer of A549 human lung cancer cells from culture, previously administered with 5 mM solution of 5-ALA for 4 hours. Twenty hours after therapy, cell cultures were stained to distinguish between living and dead cells using a laser scanning confocal microscope. To determine relative dosimetry for photodynamic therapy (PDT), 405-nm laser illumination was varied from 1 to 5 minutes with power varying from 5 to 18 mW, chosen to compare equal amounts of energy delivered to the cell culture. The SFE produced 500-line images of fluorescence at 15 Hz using the red detection channel centered at 635 nm. The results show that PDT of A549 cancer cell monolayers using 405nm light for imaging and 5-ALAinduced PpIX therapy was possible using the same SFE system. Increased duration and power of laser illumination produced an increased area of cell death upon live/dead staining. The ultrathin and flexible SFE was able to direct PDT using wide-field fluorescence imaging of a monolayer of cultured cancer cells after uptaking 5-ALA. The correlation between light intensity and duration of PDT was measured. Increased length of exposure and decreased light intensity yields larger areas of cell death than decreased length of exposure with increased light intensity.

IR780 based nanomaterials for cancer imaging and photothermal, photodynamic and combinatorial therapies.

PubMed

Alves, Cátia G; Lima-Sousa, Rita; de Melo-Diogo, Duarte; Louro, Ricardo O; Correia, Ilídio J

2018-05-05

IR780, a molecule with a strong optical absorption and emission in the near infrared (NIR) region, is receiving an increasing attention from researchers working in the area of cancer treatment and imaging. Upon irradiation with NIR light, IR780 can produce reactive oxygen species as well as increase the body temperature, thus being a promising agent for application in cancer photodynamic and photothermal therapy. However, IR780's poor water solubility, fast clearance, acute toxicity and low tumor uptake may limit its use. To overcome such issues, several types of nanomaterials have been used to encapsulate and deliver IR780 to tumor cells. This mini-review is focused on the application of IR780 based nanostructures for cancer imaging, and photothermal, photodynamic and combinatorial therapies. Copyright © 2018 Elsevier B.V. All rights reserved.

Self-assembled nanoparticles based on PEGylated conjugated polyelectrolyte and drug molecules for image-guided drug delivery and photodynamic therapy.

PubMed

Yuan, Youyong; Liu, Bin

2014-09-10

A drug delivery system based on poly(ethylene glycol) (PEG) grafted conjugated polyelectrolyte (CPE) has been developed to serve as a polymeric photosensitizer and drug carrier for combined photodynamic and chemotherapy. The amphiphilic brush copolymer can self-assemble into micellar nanopaticles (NPs) in aqueous media with hydrophobic conjugated polyelectrolyte backbone as the core and hydrophilic PEG as the shell. The NPs have an average diameter of about 100 nm, with the absorption and emission maxima at 502 and 598 nm, respectively, making them suitable for bioimaging applications. Moreover, the CPE itself can serve as a photosensitizer, which makes the NPs not only a carrier for drug but also a photosensitizing unit for photodynamic therapy, resulting in the combination of chemo- and photodynamic therapy for cancer. The half-maximal inhibitory concentration (IC50) value for the combination therapy to U87-MG cells is 12.7 μg mL(-1), which is much lower than that for the solely photodynamic therapy (25.5 μg mL(-1)) or chemotherapy (132.8 μg mL(-1)). To improve the tumor specificity of the system, cyclic arginine-glycine-aspartic acid (cRGD) tripeptide as the receptor to integrin αvβ3 overexpressed cancer cells was further incorporated to the surface of the NPs. The delivery system based on PEGylated CPE is easy to fabricate, which integrates the merits of targeted cancer cell image, chemotherapeutic drug delivery, and photodynamic therapy, making it promising for cancer treatment.

5-Aminolevulinic acid loaded ethosomal vesicles with high entrapment efficiency for in vitro topical transdermal delivery and photodynamic therapy of hypertrophic scars.

PubMed

Zhang, Zheng; Chen, Yunsheng; Xu, Heng; Wo, Yan; Zhang, Zhen; Liu, Ying; Su, Weijie; Cui, Daxiang; Zhang, Yixin

2016-11-24

Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an alternative therapy for hypertrophic scars (HS), which destroys human hypertrophic scar fibroblasts (HSF). However, the poor permeability of ALA both in HS tissue and HSF significantly restricts the PDT of HS. To overcome these barriers, ALA-loaded ethosomal vesicles (ALA-ES) were developed by a pH gradient active loading method and characterized by morphology, entrapment efficiency (EE) and stability. Results show that prepared ALA-ES are homogenous spherical lamellar vesicles, 53 ± 7 nm in size, 50.6 ± 2.3% in EE and have excellent stability. In vitro transdermal delivery studies through HS tissue were carried out by using Franz diffusion cells. Compared to the traditional ALA hydroalcoholic solution (ALA-HA), ALA-ES achieve higher drug retention in less administration time, and fluorescence microscopy showed that ALA-ES penetrate into the deeper dermis of HS in a shorter time, indicating that ALA-ES can enhance the penetration of ALA into HS. Additionally, ALA-ES was visualized in HS tissue for the first time by transmission electron microscopy (TEM). The irregular and collapsed ALA-ES suggest that they can squeeze through narrow spaces to the target area and release ALA into HS. Taking HSF as the target, the transcellular delivery of ALA-ES into HSF cells was investigated by intracellular protoporphyrin IX (PpIX) accumulation. The efficiency of PDT for HSF cells, including the formation of reactive oxygen species (ROS) and cell apoptosis, were also well investigated. Furthermore, the detailed changes of HSF were observed by TEM. The results strongly indicate that ALA-ES can facilitate ALA penetration into HSF cells, and can cause a higher level of cell apoptosis or necrosis than ALA-HA. ALA-ES with high EE is therefore a promising transdermal delivery system for topical ALA administration and has great potential in ALA-PDT of HS.

Topical calcitriol prior to photodynamic therapy enhances treatment efficacy in non-melanoma skin cancer mouse models.

PubMed

Rollakanti, Kishore; Anand, Sanjay; Maytin, Edward V

2015-03-02

Non-melanoma skin cancers (NMSCs) such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common form of human cancer worldwide, and their incidence is increasing. Photodynamic therapy (PDT), mediated by topically applied aminolevulinic acid (ALA) and subsequent exposure to light (either a laser or a noncoherent source), is being increasingly used for the treatment of dermatological disorders, including BCC and SCC. However, therapeutic responses of NMSCs to ALA-PDT are currently not superior to standard therapies, although the latter have undesirable side effects including scarring. In this study, we report that preconditioning of skin tumors with calcitriol (active form of Vitamin D; Vit D) prior to ALA-PDT, significantly improves the treatment outcome. In BCC and UVB-induced SCC mouse models, we identified an increase in tumor-specific accumulation of ALA induced photosensitizer (protoporphyrin IX, PpIX) due to Vit D preconditioning, of up to 6-fold in vivo . In addition, increased expression of differentiation (145 fold, p < 0.02) and proliferation (42 fold, p < 0.005) markers were identified in BCC tumors, all leading to increased tumor destruction (18.3 fold, p < 0.03) with the combination approach, as compared to ALA-PDT alone. Histomorphological changes identified using hematoxylin and eosin staining, and results of TUNEL staining, together documented a beneficial effect of Vit D pretreatment upon tumor cell death. We conclude that this new combination approach with Vit D and ALA-PDT has great potential to achieve complete remission of NMSC tumors, with excellent cosmetic results and an overall beneficial impact upon patient care.

Topical calcitriol prior to photodynamic therapy enhances treatment efficacy in non-melanoma skin cancer mouse models

PubMed Central

Rollakanti, Kishore; Anand, Sanjay; Maytin, Edward V.

2015-01-01

Non-melanoma skin cancers (NMSCs) such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common form of human cancer worldwide, and their incidence is increasing. Photodynamic therapy (PDT), mediated by topically applied aminolevulinic acid (ALA) and subsequent exposure to light (either a laser or a noncoherent source), is being increasingly used for the treatment of dermatological disorders, including BCC and SCC. However, therapeutic responses of NMSCs to ALA-PDT are currently not superior to standard therapies, although the latter have undesirable side effects including scarring. In this study, we report that preconditioning of skin tumors with calcitriol (active form of Vitamin D; Vit D) prior to ALA-PDT, significantly improves the treatment outcome. In BCC and UVB-induced SCC mouse models, we identified an increase in tumor-specific accumulation of ALA induced photosensitizer (protoporphyrin IX, PpIX) due to Vit D preconditioning, of up to 6-fold in vivo. In addition, increased expression of differentiation (145 fold, p < 0.02) and proliferation (42 fold, p < 0.005) markers were identified in BCC tumors, all leading to increased tumor destruction (18.3 fold, p < 0.03) with the combination approach, as compared to ALA-PDT alone. Histomorphological changes identified using hematoxylin and eosin staining, and results of TUNEL staining, together documented a beneficial effect of Vit D pretreatment upon tumor cell death. We conclude that this new combination approach with Vit D and ALA-PDT has great potential to achieve complete remission of NMSC tumors, with excellent cosmetic results and an overall beneficial impact upon patient care. PMID:25983370

Topical calcitriol prior to photodynamic therapy enhances treatment efficacy in non-melanoma skin cancer mouse models

NASA Astrophysics Data System (ADS)

Rollakanti, Kishore; Anand, Sanjay; Maytin, Edward V.

2015-03-01

Non-melanoma skin cancers (NMSCs) such as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common form of human cancer worldwide, and their incidence is increasing. Photodynamic therapy (PDT), mediated by topically applied aminolevulinic acid (ALA) and subsequent exposure to light (either a laser or a noncoherent source), is being increasingly used for the treatment of dermatological disorders, including BCC and SCC. However, therapeutic responses of NMSCs to ALA-PDT are currently not superior to standard therapies, although the latter have undesirable side effects including scarring. In this study, we report that preconditioning of skin tumors with calcitriol (active form of Vitamin D; Vit D) prior to ALA-PDT, significantly improves the treatment outcome. In BCC and UVB-induced SCC mouse models, we identified an increase in tumor-specific accumulation of ALA induced photosensitizer (protoporphyrin IX, PpIX) due to Vit D preconditioning, of up to 6- fold in vivo. In addition, increased expression of differentiation (145 fold, p < 0.02) and proliferation (42 fold, p <0.005) markers were identified in BCC tumors, all leading to increased tumor destruction (18.3 fold, p < 0.03) with the combination approach, as compared to ALA-PDT alone. Histomorphological changes identified using hematoxylin and eosin staining, and results of TUNEL staining, together documented a beneficial effect of Vit D pretreatment upon tumor cell death. We conclude that this new combination approach with Vit D and ALA-PDT has great potential to achieve complete remission of NMSC tumors, with excellent cosmetic results and an overall beneficial impact upon patient care.

Enhancement of selectivity for photodynamic therapy

NASA Astrophysics Data System (ADS)

Bedwell, Joanne

Photodynamic Therapy (PDT) is a technique for producing localised tissue damage with low power light following prior administration of a photosensitising drug. The promise of PDT has been based on the selective retention of photosensitisers by tumours, but this aspect has been over-emphasised with a maximum ratio of photosensitiser concentration of 3:1, tumour to normal, for extracranial tumours and current drugs. This makes selective tumour necrosis difficult to achieve. This thesis explores ways in which selectivity may be improved. Aluminium sulphonated phthalocyanine (AlSPc) has better photochemical properties than the widely used HpD and Photofrin II, but has the same tumour selectivity, although the ratio was improved marginally using its disulphonated component. However, when used in conjunction with the radioprotective drug W7, in a rat colon cancer model, tumour necrosis was the same as without W7 while there was no damage to adjacent normal colon. A radical new approach is to give 5-aminolaevulinic acid (ALA) which induces endogenous production of the photosensitiser protoporphyrin IX. This improves selectivity in the rat colon cancer to 6:1 (tumour to normal mucosa), but also sensitises the mucosa selectively compared with the underlying muscle (10:1), giving a tumour to muscle ratio of 60:1. This has enormous potential for treating small tumours or areas of dysplasia in a range of hollow organs. ALA also has the major advantages of a short optimum drug to light time (typically 4-6 hours), short duration of skin sensitivity (approximately 24 hours) and it can be given orally with minimal systemic toxicity. This work has also shown in vitro that PDT with AlSPc sensitisation can kill helicohacter pylori at doses unlikely to affect gastric mucosa. In conclusion, by careful choice of photosensitising agents and treatment regimes, it is possible to limit PDT effects to abnormal tissues, and even if there is some normal tissue damage, in most cases, this heals

Comparative study of the bactericidal effects of indocyanine green- and methyl aminolevulinate-based photodynamic therapy on Propionibacterium acnes as a new treatment for acne.

PubMed

Choi, Seung-Hwan; Seo, Jeong-Wan; Kim, Ki-Ho

2018-05-03

Acne vulgaris is one of the most common dermatological problems, and its therapeutic options include topical and systemic retinoids and antibiotics. However, increase in problems associated with acne treatment, such as side-effects from conventional agents and bacterial resistance to antibiotics, has led to greater use of photodynamic therapy. The purpose of this study was to compare the bactericidal effects of indocyanine green- and methyl aminolevulinate-based photodynamic therapy on Propionibacterium acnes. P. acnes were cultured under anaerobic conditions; then they were divided into three groups (control, treated with indocyanine green and treated with methyl aminolevulinate) and illuminated with different lights (630-nm light-emitting diode, 805-nm diode laser and 830-nm light-emitting diode). The bactericidal effects were evaluated by comparing each group's colony-forming units. The cultured P. acnes were killed with an 805-nm diode laser and 830-nm light-emitting diode in the indocyanine green group. No bactericidal effects of methyl aminolevulinate-based photodynamic therapy were identified. The clinical efficacy of indocyanine green-based photodynamic therapy in 21 patients was retrospectively analyzed. The Korean Acne Grading System was used to evaluate treatment efficacy, which was significantly decreased after treatment. The difference in the efficacy of the 805-nm diode laser and 830-nm light-emitting diode was not statistically significant. Although the methyl aminolevulinate-based photodynamic therapy showed no bactericidal effect, the indocyanine green-based photodynamic therapy has bactericidal effect and clinical efficacy. © 2018 Japanese Dermatological Association.

A Comprehensive Tutorial on In Vitro Characterization of New Photosensitizers for Photodynamic Antitumor Therapy and Photodynamic Inactivation of Microorganisms

PubMed Central

Maisch, Tim; Berneburg, Mark; Plaetzer, Kristjan

2013-01-01

In vitro research performed on eukaryotic or prokaryotic cell cultures usually represents the initial step for characterization of a novel photosensitizer (PS) intended for application in photodynamic therapy (PDT) of cancer or photodynamic inactivation (PDI) of microorganisms. Although many experimental steps of PS testing make use of the wide spectrum of methods readily employed in cell biology, special aspects of working with photoactive substances, such as the autofluorescence of the PS molecule or the requirement of light protection, need to be considered when performing in vitro experiments in PDT/PDI. This tutorial represents a comprehensive collection of operative instructions, by which, based on photochemical and photophysical properties of a PS, its uptake into cells, the intracellular localization and photodynamic action in both tumor cells and microorganisms novel photoactive molecules may be characterized for their suitability for PDT/PDI. Furthermore, it shall stimulate the efforts to expand the convincing benefits of photodynamic therapy and photodynamic inactivation within both established and new fields of applications and motivate scientists of all disciplines to get involved in photodynamic research. PMID:23762860

Combination therapies in adjuvant with topical ALA-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premalignant lesions

NASA Astrophysics Data System (ADS)

Yang, Deng-Fu; Hsu, Yih-Chih

2012-03-01

In Taiwan, oral cancer has becomes the fastest growth male cancer disease due to the betel nut chewing habit combing with smoking and alcohol-drinking lifestyle of people. In order to eliminate the systemic phototoxic effect of 5-aminolevulinic acid (ALA), this study was designed to use a topical ALA-mediated PDT for treatment of DMBA-induced hamster buccal pouch precancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 10 to 12 weeks. Cancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical ALA-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when ALA reached its peak level in the lesional epithelial cells after topical application of ALA gel. We found that ALA reached its peak level in precancerous lesions about 2.5 hrs after topical application of ALA gel. The cancerous lesions in hamsters were then treated with topical ALA -mediated PDT with light exposure dose of 150 J/cm2 using LED 635 nm fiber-guided light device. Visual examination demonstrated that adjuvant topical ALA -mediated PDT group has shown better therapeutic results in compared to those of non-adjuvant topical ALA-mediated PDT group for DMBA-induced hamster buccal pouch precancerous lesions.

Development of low-cost devices for image-guided photodynamic therapy treatment of oral cancer in global health settings

NASA Astrophysics Data System (ADS)

Liu, Hui; Rudd, Grant; Daly, Liam; Hempstead, Joshua; Liu, Yiran; Khan, Amjad P.; Mallidi, Srivalleesha; Thomas, Richard; Rizvi, Imran; Arnason, Stephen; Cuckov, Filip; Hasan, Tayyaba; Celli, Jonathan P.

2016-03-01

Photodynamic therapy (PDT) is a light-based modality that shows promise for adaptation and implementation as a cancer treatment technology in resource-limited settings. In this context PDT is particularly well suited for treatment of pre-cancer and early stage malignancy of the oral cavity, that present a major global health challenge, but for which light delivery can be achieved without major infrastructure requirements. In recent reports we demonstrated that a prototype low-cost batterypowered 635nm LED light source for ALA-PpIX PDT achieves tumoricidal efficacy in vitro and vivo, comparable to a commercial turn-key laser source. Here, building on these reports, we describe the further development of a prototype PDT device to enable intraoral light delivery, designed for ALA- PDT treatment of precancerous and cancerous lesions of the oral cavity. We evaluate light delivery via fiber bundles and customized 3D printed light applicators for flexible delivery to lesions of varying size and position within the oral cavity. We also briefly address performance requirements (output power, stability, and light delivery) and present validation of the device for ALA-PDT treatment in monolayer squamous carcinoma cell cultures.

Induced Protoporphyrin IX Accumulation by the δ-Aminolevulinic Acid in Bacteria and its Potential Use in the Photodynamic Therapy

NASA Astrophysics Data System (ADS)

Brígido-Aparicio, Cyntiha; Ramón-Gallegos, Eva; Arenas-Huertero, Francisco Jesús; Uribe-Hernández, Raúl

2008-08-01

The increasing incident of resistant strains to antibiotic has encouraged the search of new antibacterial treatments, such as the photodynamic therapy. In recent years, photodynamic therapy has demonstrated being a good technology for the treatment of recurrent bacteria infection. PDT presents a hopeful approach to eliminate Gram positive and negative bacteria in immunological compromised patients. This therapy uses a laser in combination with a photosensibilizer in presence of intracellular molecular oxygen. The process generates an effect of phototoxicity in bacterial cells. The aim of this work was to determine the in vitro conditions to accumulate PpIX in effective concentrations in Staphylococcus aureus ATCC25923 and Streptococcus pyogenes, which are responsible of human cutaneous diseases. A cellular suspension of both strains was prepared in TSB to obtain growth in Log-phase, then, the suspensions were adjusted to a final concentration of 2.61×108 cells/mL. The strains were exposed to increasing concentrations from 0 to 160μg/mL of δ-ALA in order to determinate the concentration that induces the biggest accumulation of PpIX. PpIX was measured using the Piomelli method modified for bacteria. The concentration selected was 40 mg/mL of ALA. It was found that in basal concentration of δ-ALA (0 μg/mL) both strains accumulated similar amount of PpIX. In concentrations of 5 mg/mL of δ-ALA it was observed a significant (p<0.001) increment in PpIX concentration. Finally it was realized a kinetic to determinate the optimal accumulation over the time at 0, 5, 10, 15 and 30 min, and 1, 2, 4, 8, 16 and 32 h. It was found that the ideal time for PDT application, in both strains, was 24 h because in smaller times there was not statistically significant difference. The S. aureus ATCC25923 accumulated significantly the biggest concentration of PpIX with regard to S. pyogenes. In conclusion, it was found that the optimal conditions to apply PDT will be to expose both

Topical hexylaminolevulinate and aminolevulinic acid photodynamic therapy: complete arteriole vasoconstriction occurs frequently and depends on protoporphyrin IX concentration in vessel wall.

PubMed

Middelburg, T A; de Bruijn, H S; Tettero, L; van der Ploeg van den Heuvel, A; Neumann, H A M; de Haas, E R M; Robinson, D J

2013-09-05

Vascular responses to photodynamic therapy (PDT) may influence the availability of oxygen during PDT and the extent of tumor destruction after PDT. However, for topical PDT vascular effects are largely unknown. Arteriole and venule diameters were measured before and after hexylaminolevulinate (HAL) and aminolevulinic acid (ALA) PDT and related to the protoporphyrin IX (PpIX) concentration in the vessel wall. A mouse skin fold chamber model and an intravital confocal microscope allowed direct imaging of the subcutaneous vessels underlying the treated area. In both HAL and ALA groups over 60% of arterioles constricted completely, while venules generally did not respond, except for two larger veins that constricted partially. Arteriole vasoconstriction strongly correlated with PpIX fluorescence intensity in the arteriole wall. Total PpIX fluorescence intensity was significantly higher for HAL than ALA for the whole area that was imaged but not for the arteriole walls. In conclusion, complete arteriole vasoconstriction occurs frequently in both HAL and ALA based topical PDT, especially when relatively high PpIX concentrations in arteriole walls are reached. Vasoconstriction will likely influence PDT effect and should be considered in studies on topical HAL and ALA-PDT. Also, our results may redefine the vasculature as a potential secondary target for topical PDT. Copyright © 2013 Elsevier B.V. All rights reserved.

Randomized Vehicle-Controlled Study of Short Drug Incubation Aminolevulinic Acid Photodynamic Therapy for Actinic Keratoses of the Face or Scalp.

PubMed

Pariser, David M; Houlihan, Anna; Ferdon, Mary Beth; Berg, James E

2016-03-01

Aminolevulinic acid photodynamic therapy (ALA-PDT) can be effective and well tolerated when applied over a broad area and for short drug incubation times. To evaluate the effect of short-incubation time and application method on the safety and efficacy of ALA-PDT versus vehicle (VEH-PDT) in the treatment of actinic keratoses (AKs) of the face or scalp. Aminolevulinic acid or VEH was applied to face or scalp as a broad area application for 1, 2, or 3 hours or as a spot application for 2 hours before blue light activation. An identical treatment was repeated at Week 8 if any AK lesions remained. Median AK clearance rate for ALA-treated subjects ranged from 68% to 79% at Week 12, compared with 7% of the VEH-treated group (p < .0001). Complete clearance rate for ALA-treated subjects ranged from 17% (8/46) to 30% (14/47) at Week 12, compared with 2% (1/46) of the VEH-treated group (p = .0041). The safety profile seen in this study is consistent with previously reported side effects of the therapy. Short-incubation ALA-PDT was found to be superior to VEH-PDT for AK lesion clearance. A second treatment improves efficacy.

A suppository kit for metronomic photodynamic therapy: The elimination of rectal cancer in situ.

PubMed

Shi, X F; Jin, W D; Gao, H; Yin, H J; Li, Y X; Huang, H; Ma, H; Dong, H J

2018-04-01

Metronomic photodynamic therapy (mPDT) was developed to improve tumor-specific responses through cell death by apoptosis. We developed an mPDT suppository kit including ALA and LED suppositories and analyzed its killing effect on rectal tumors in rabbits. The ALA (10 wt%) suppository was prepared using ALA powder, type 36 semi-synthetic fatty acid glyceride, and azone. The LED suppository was constructed by encapsulating LED units and a circuit in transparent epoxy resin. VX2 cells were injected into the rectal submucosa of rabbits to establish a carcinoma model in situ. The ALA suppository was inserted into the rectal cavity for 30 min of uptake and activated for 1 h by the LED suppository at a power density of 20 mW/cm 2 . The mPDT process was repeated three times once a day. MRI was used to monitor tumor growth, histopathology and TUNEL staining were performed at 14 days after mPDT. The overall response rate was 60% in the mPDT group using the kit in which the tumor size was decreased up to about 50% at 7 days post-mPDT and almost eliminated at 14 days. HE staining showed that only 6.16% of the tumor tissue remained after mPDT treatment. TUNEL detection showed that the apoptosis rate was 18.9%. We verified the killing effect of the mPDT suppository kit on rectal tumors in rabbits based on mPDT that induced tumor cell apoptosis. Copyright © 2018 Elsevier B.V. All rights reserved.

Reduction of thermal damage in photodynamic therapy by laser irradiation techniques.

PubMed

Lim, Hyun Soo

2012-12-01

General application of continuous-wave (CW) laser irradiation modes in photodynamic therapy can cause thermal damage to normal tissues in addition to tumors. A new photodynamic laser therapy system using a pulse irradiation mode was optimized to reduce nonspecific thermal damage. In in vitro tissue specimens, tissue energy deposition rates were measured in three irradiation modes, CW, pulse, and burst-pulse. In addition, methods were tested for reducing variations in laser output and specific wavelength shifts using a thermoelectric cooler and thermistor. The average temperature elevation per 10 J/cm2 was 0.27°C, 0.09°C, and 0.08°C using the three methods, respectively, in pig muscle tissue. Variations in laser output were controlled within ± 0.2%, and specific wavelength shift was limited to ± 3 nm. Thus, optimization of a photodynamic laser system was achieved using a new pulse irradiation mode and controlled laser output to reduce potential thermal damage during conventional CW-based photodynamic therapy.

Topical delivery of a preformed photosensitizer for photodynamic therapy of cutaneous lesions

NASA Astrophysics Data System (ADS)

Oleinick, Nancy L.; Kenney, Malcolm E.; Lam, Minh; McCormick, Thomas; Cooper, Kevin D.; Baron, Elma D.

2012-02-01

Photosensitizers for photodynamic therapy (PDT) are most commonly delivered to patients or experimental animals via intravenous injection. After initial distribution throughout the body, there can be some preferential accumulation within tumors or other abnormal tissue in comparison to the surrounding normal tissue. In contrast, the photosensitizer precursor, 5-aminolevulinic acid (ALA) or one of its esters, is routinely administered topically, and more specifically, to target skin lesions. Following metabolic conversion to protoporphyrin IX, the target area is photoilluminated, limiting peripheral damage and targeting the effective agent to the desired region. However, not all skin lesions are responsive to ALA-PDT. Topical administration of fully formed photosensitizers is less common but is receiving increased attention, and some notable advances with selected approved and experimental photosensitizers have been published. Our team has examined topical administration of the phthalocyanine photosensitizer Pc 4 to mammalian (human, mouse, pig) skin. Pc 4 in a desired formulation and concentration was applied to the skin surface at a rate of 5-10 μL/cm2 and kept under occlusion. After various times, skin biopsies were examined by confocal microscopy, and fluorescence within regions of interest was quantified. Early after application, images show the majority of the Pc 4 fluorescence within the stratum corneum and upper epidermis. As a function of time and concentration, penetration of Pc 4 across the stratum corneum and into the epidermis and dermis was observed. The data indicate that Pc 4 can be delivered to skin for photodynamic activation and treatment of skin pathologies.

Photodynamic therapy for recurrent respiratory papillomatosis.

PubMed

Lieder, Anja; Khan, Muhammad K; Lippert, Burkard M

2014-06-05

Recurrent respiratory papillomatosis (RRP) is a benign condition of the mucosa of the upper aerodigestive tract. It is characterised by recurrent papillomatous lesions and is associated with human papillomavirus (HPV). Frequent recurrence and rapid papilloma growth are common and in part responsible for the onset of potentially life-threatening symptoms. Most patients afflicted by the condition will require repeated surgical treatments to maintain their airway, and these may result in scarring and voice problems. Photodynamic therapy introduces a light-sensitising agent, which is administered either orally or by injection. This substance (called a photo-sensitiser) is selectively retained in hyperplastic and neoplastic tissue, including papilloma. It is then activated by light of a specific wavelength and may be used as a sole or adjuvant treatment for RRP. To assess the effects of photodynamic therapy in the management of recurrent respiratory papillomatosis (RRP) in children and adults. We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the search was 27 January 2014. Randomised controlled trials utilising photodynamic therapy as sole or adjuvant therapy in participants of any age with proven RRP versus control intervention. Primary outcome measures were symptom improvement (respiratory distress/dyspnoea and voice quality), quality of life improvement and recurrence-free interval. Secondary outcomes included reduction in the frequency of surgical intervention, reduction in disease volume and adverse effects of treatment.   We used the standard methodological procedures expected by The Cochrane Collaboration. Meta-analysis was not possible and results are presented descriptively. We included one trial with a total of 23

Smart pH-responsive upconversion nanoparticles for enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

PubMed

Wang, Sheng; Zhang, Lei; Dong, Chunhong; Su, Lin; Wang, Hanjie; Chang, Jin

2015-01-01

A smart pH-responsive photodynamic therapy system based on upconversion nanoparticle loaded PEG coated polymeric lipid vesicles (RB-UPPLVs) was designed and prepared. These RB-UPPLVs which are promising agents for deep cancer photodynamic therapy applications can achieve enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

Enhancement and optimization of PpIX-based photodynamic therapy of skin cancer: translational studies from bench to clinic

NASA Astrophysics Data System (ADS)

Maytin, Edward V.; Anand, Sanjay; Baran, Christine; Honari, Golara; Lohser, Sara; Kyei, Angela; Bailin, Philip; Pogue, Brian W.

2009-02-01

Nonmelanoma skin carcinomas are the most common of all human cancers. Photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA) has been used to treat these tumors, but has shown variable results. We are pursuing a multifaceted approach toward optimizing tumor responsiveness. First, a new paradigm is being developed in which tumors are pretreated with differentiation-inducing agents, e.g. methotrexate or Vitamin D, to enhance synthesis of protoporphyrin IX (PpIX) and improve tumor cell killing upon exposure to 635 nm light. This principle was first elucidated in cell culture studies, and has now been shown to hold true for murine skin tumors, and for a human subcutaneous tumor model (A431 cells injected in nude mice). Clinical trials to test methotrexate and Vitamin D as augmenting agents for ALA-PDT of nonmelanoma skin cancer are being designed. Second, better methods to measure PpIX in patients' skin tumors in real time are being developed. In a clinical study to measure PpIX in patients with dysplastic skin lesions, in vivo fluorescence dosimetry was used to measure the accumulation of PpIX over time, and revealed that intralesional PpIX may reach clinically-useful levels earlier than previously thought for the treatment of actinic keratoses. In a second clinical study to examine depth of PpIX production in nonmelanoma skin cancer, the depth of PpIX within BCC tumors was found at relatively deep levels (>1 mm) in some tumor nests, but not in others. Production of PpIX in deep squamous cell carcinoma was very low. In summary, molecular approaches such as differentiation therapy to enhance ALA-PDT for individual patients may ultimately be needed to help to improve skin cancer responses to this modality.

Porphyrin-based Nanostructure-Dependent Photodynamic and Photothermal Therapies

NASA Astrophysics Data System (ADS)

Jin, Cheng S.

This thesis presents the investigation of nanostructure-dependent phototherapy. We reviewed the liposomal structures for delivery of photosensitizers, and introduced a novel class of phototransducing liposomes called "porphysomes". Porphysomes are self-assembled from high packing density of pyropheophorbide alpha-conjugated phospholipids, resulting in extreme self-quenching of porphyrin fluorescence and comparable optical absorption to gold nanoparticles for high photothermal efficiency. We demonstrated this self-assembly of porphyrin-lipid conjugates converts a singlet oxygen generating mechanism (photodynamic therapy PDT activity) of porphyrin to photothermal mechanism (photothermal therapy PTT activity). The efficacy of porphysome-enhanced PTT was then evaluated on two pre-clinical animal models. We validated porphysome-enabled focal PTT to treat orthotopic prostate cancer using MRI-guided focal laser placement to closely mimic the current clinic procedure. Furthermore, porphysome-enabled fluorescence-guided transbronchial PTT of lung cancer was demonstrated in rabbit orthotopic lung cancer models, which led to the development of an ultra-minimally invasive therapy for early-stage peripheral lung cancer. On the other hand, the nanostructure-mediated conversion of PDT to PTT can be switched back by nanoparticle dissociation. By incorporating folate-conjugated phospholipids into the formulation, porphysomes were internalized into cells rapidly via folate receptor-mediated endocytosis and resulted in efficient disruption of nanostructures, which turned back on the photodynamic activity of densely packed porphyrins, making a closed loop of conversion between PDT and PTT. The multimodal imaging and therapeutic features of porphysome make it ideal for future personalized cancer treatments.

Photodynamic therapy using a novel irradiation source, LED lamp, is similarly effective to photodynamic therapy using diode laser or metal-halide lamp on DMBA- and TPA-induced mouse skin papillomas.

PubMed

Takahashi, Hidetoshi; Nakajima, Susumu; Ogasawara, Koji; Asano, Ryuji; Nakae, Yoshinori; Sakata, Isao; Iizuka, Hajime

2014-08-01

Photodynamic therapy (PDT) is useful for superficial skin tumors such as actinic keratosis and Bowen disease. Although PDT is non-surgical and easily-performed treatment modality, irradiation apparatus is large and expensive. Using 7, 12-dimethylbenz[a]anthracene (DMBA) and 12-ο-tetradecanoylphorbol-13-acetate (TPA)-induced mouse skin papilloma model, we compared the efficacy of TONS501- and ALA-PDT with a LED lamp, a diode laser lamp or a metal-halide lamp on the skin tumor regression. TONS501-PDT using 660 nm LED lamp showed anti-tumor effect at 1 day following the irradiation and the maximal anti-tumor effect was observed at 3 days following the irradiation. There was no significant difference in the anti-tumor effects among TONS501-PDT using LED, TONS501-PDT using diode laser, and 5-aminolevulinic acid hydrochloride (ALA)-PDT using metal-halide lamp. Potent anti-tumor effect on DMBA- and TPA-induced mouse skin papilloma was observed by TONS501-PDT using 660 nm LED, which might be more useful for clinical applications. © 2014 Japanese Dermatological Association.

Topical photodynamic therapy with 5-aminolevulinic acid in the treatment of actinic keratoses: a first clinical study

NASA Astrophysics Data System (ADS)

Karrer, Sigrid; Szeimies, Rolf-Markus; Sauerwald, Angela; Landthaler, Michael

1996-01-01

In this first clinical study performed according to GCP- (good clinical practice) guidelines, efficacy, and tolerability of topical photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) were tested in the treatment of actinic keratoses. Ten patients (6 f, 4 m) with 36 lesions (19 located on hands and arms, 17 on the head) received ALA-PDT once. Five to six hours after occlusive application of ALA (water-in-oil-emulsion containing 10% ALA) irradiation was performed with an incoherent light source. Up to 3 months after treatment patients were monitored. A score evaluating infiltration and keratosis of treated actinic keratoses allowed us to estimate therapeutic efficacy. Compared to the initial score (100%) significantly lower score-sums were observed at the 28 day follow-up at both localizations (head: 15%; hand: 67%). Complete remission (score sum 0) resulted in 71% of actinic keratoses localized on the head. Except for slight pain and burning sensations during and after irradiation there were no notable side effects. This study proved good efficacy and tolerability of topical PDT in the treatment of actinic keratoses. Whether PDT is able to compete with established treatment modalities remains to be shown in further studies.

A New Modality for Cancer Treatment--Nanoparticle Mediated Microwave Induced Photodynamic Therapy.

PubMed

Yao, Mengyu; Ma, Lun; Li, Lihua; Zhang, Junying; Lim, Rebecca; Chen, Wei; Zhang, Yu

2016-10-01

Photodynamic therapy (PDT) has attracted ever-growing attention as a promising modality for cancer treatment. However, due to poor tissue penetration by light, photodynamic therapy has rarely been used for deeply situated tumors. This problem can be solved if photosensitizers are activated by microwaves (MW) that are able to penetrate deeply into tissues. Here, for the first time, we report microwave-induced photodynamic therapy and exploit copper cysteamine nanoparticles as a new type of photosensitizer that can be activated by microwaves to produce singlet oxygen for cancer treatment. Both in vitro and in vivo studies on a rat osteosarcoma cell line (UMR 106-01) have shown significant cell destruction using copper cysteamine (Cu-Cy) under microwave activation. The heating effects and the release of copper ions from Cu-Cy upon MW stimulation are the main mechanisms for the generation of reactive oxygen species that are lethal bullets for cancer destruction. The copper cysteamine nanoparticle-based microwave-induced photodynamic therapy opens a new door for treating cancer and other diseases.

Photodynamic therapy for treatment subretinal neovascularization

NASA Astrophysics Data System (ADS)

Avetisov, Sergey E.; Budzinskaja, Maria V.; Kiseleva, Tatyana N.; Balatskaya, Natalia V.; Gurova, Irina V.; Loschenov, Viktor B.; Shevchik, Sergey A.; Kuzmin, Sergey G.; Vorozhtsov, Georgy N.

2007-07-01

This work are devoted our experience with photodynamic therapy (PDT) with <> for patients with choroidal neovascularization (CNV). 18 patients with subfoveal CNV in age-related macular degeneration (AMD), 24 patients with subfoveal CNV in pathological myopia (PM) and 4 patients with subfoveal CNV associated with toxoplasmic retinochoroiditis were observed. CNV was 100% classic in all study patients. Standardized protocol refraction, visual acuity testing, ophthalmologic examinations, biomicroscopy, fluorescein angiography, and ultrasonography were performed before treatment and 1 month, 3 months, 6 months, and 1 year after treatment; were used to evaluate the results of photodynamic therapy with <> (0.02% solution of mixture sulfonated aluminium phtalocyanine 0.05 mg/kg, intravenously). A diode laser (<>, Inc, Moscow) was used operating in the range of 675 nm. Need for retreatment was based on fluorescein angiographic evidence of leakage at 3-month follow-up intervals. At 3, 6, 9 month 26 (56.5%) patients had significant improvement in the mean visual acuity. At the end of the 12-month minimal fluorescein leakage from choroidal neovascularization was seen in 12 (26.1%) patients and the mean visual acuity was slightly worse than 0.2 which was not statistically significant as compared with the baseline visual acuity. Patients with fluorescein leakage from CNV underwent repeated PDT with <>. 3D-mode ultrasound shown the decreasing thickness of chorioretinal complex in CNV area. Photodynamic therapy with <> can safely reduce the risk of severe vision loss in patients with predominantly classic subfoveal choroidal neovascularization secondary to AMD, PM and toxoplasmic retinochoroiditis.

In vivo study of ALA PLGA nanoparticles-mediated PDT for treating cutaneous squamous cell carcinoma

NASA Astrophysics Data System (ADS)

Wang, Xiaojie; Shi, Lei; Huang, Zheng; Wang, Xiuli

2014-09-01

Background: Squamous cell carcinoma (SCC) is a common skin cancer and its treatment is still a challenge. Although topical photodynamic therapy (PDT) is effective for treating in situ and superficial SCC, the effectiveness of topical ALA delivery to thick SCC can be limited by its bioavailability. Polylactic-co-glycolic acid nanopartieles (PLGA NPs) might provide a promising ALA delivery strategy. The aim of this study was to evaluate the efficacy of ALA PLGA NPs PDT for the treatment of cutaneous SCC in a mouse model. Methods: ALA loaded PLGA NPs were prepared and characterized. The therapeutic efficacy of ALA PLGA NP mediated PDT in treating UV-induced cutaneous SCC in the mice model were examined. Results: In vivo study showed that ALA PLGA NPs PDT were more effective than free ALA of the same concentration in treating mouse cutaneous SCC. Conclusion: ALA PLGA NPs provides a promising strategy for delivering ALA and treating cutaneous SCC.

Randomized, Controlled Trial of Fractional Carbon Dioxide Laser Resurfacing Followed by Ultrashort Incubation Aminolevulinic Acid Blue Light Photodynamic Therapy for Actinic Keratosis.

PubMed

Alexiades, Macrene

2017-08-01

Aminolevulinic acid (ALA) photodynamic therapy (PDT) is an established treatment option for actinic keratosis (AK), and recently fractional carbon dioxide (CO2) laser was shown to improve outcomes; but studies of short incubation photosensitizer are lacking. Assess the efficacy of short incubation ALA followed by blue light PDT with and without previous fractional CO2 treatment for the treatment of AK. Randomized, paired split-design, controlled trial of fractional CO2 followed by ultrashort 15-minute versus 30-minute incubation ALA and blue light PDT for the treatment of AK on the face. The complete clearance rates (CRs) at 8 weeks after ALA PDT with and without FxCO2 at 30- and 15-minute ALA incubation times were 89.78% (+FxCO2) versus 71.20% CR (-FxCO2) at 30', and 86.38% (+FxCO2) versus 69.23% (-FxCO2) at 15' ALA incubation. All lesion improvements were statistically significant. This randomized, comparative paired group controlled clinical study demonstrates that ultrashort 15- and 30-minute incubation ALA PDTs are of limited efficacy for the treatment of AK. Pretreatment with fractional ablative resurfacing yields statistically significant greater AK clearance with ALA-PDT at ultrashort ALA incubations followed by blue light.

Is topical delta-aminolevulinic acid adequate for photodynamic therapy in Barrett's esophagus? A pilot study.

PubMed

Ortner, M -A; Zumbusch, K; Liebetruth, J; Ebert, B; Fleige, B; Dietel, M; Lochs, H

2002-08-01

The methods of endoscopic ablation of metaplastic and dysplastic areas in Barrett's esophagus so far described, are not satisfactory with respect to efficacy and safety. Therefore we investigated whether photodynamic therapy (PDT) with topical delta-aminolevulinic acid (delta-ALA) leads to ablation of specialized columnar epithelium and eradication of low-grade dysplasia while not producing phototoxicity and systemic side effects. 14 patients with histologically proven Barrett's esophagus, seven of whom had evidence of low-grade dysplasia, underwent endoscopic treatment with topical delta-ALA. Photoactivation (wavelength, 632 nm) was performed at 1.5 - 2 hours after drug administration using an argon dye laser. Patients received omeprazole 80 mg daily for 2 months; thereafter; maintenance therapy depended on reflux symptoms. Patients were endoscopically re-evaluated after 7 days, and subsequently at 3, 6, 12 and up to 48 months (mean follow up 33 months). Re-treatment with high-dose topical delta-ALA was offered to the 11 patients with remaining metaplasia and was carried out in five of them. Low-grade dysplasia was eradicated in all patients. One patient with no dysplasia before PDT developed a high-grade dysplasia after PDT. Complete ablation of Barrett's metaplasia was observed in 21 % of the patients after the first treatment session and in 20 % after the second treatment session. The mean reduction in the length of Barrett's metaplasia was 1.54 +/- 1.29 cm after the first PDT session and 1.02 +/- 0.80 cm after the second PDT session. Post-endoscopic pain and photosensitivity reactions were less frequent with low-dose delta-ALA PDT than with high-dose PDT (pain 15 %, 100 %, respectively; P = 0.001 by Fisher's exact test; phototoxicity, 0 %, 50 %, respectively; P = 0.021 by Fisher's exact test). Low-dose topical administration of delta-ALA provides ablation of low-grade dysplasia in the range obtained with oral delta-ALA. In addition, it is safe and well

In vitro investigation of efficient photodynamic therapy using a nonviral vector; hemagglutinating virus of Japan envelope

NASA Astrophysics Data System (ADS)

Sakai, Makoto; Fujimoto, Naohiro; Ishii, Katsunori; Nakamura, Hiroyuki; Kaneda, Yasufumi; Awazu, Kunio

2012-07-01

Photodynamic therapy (PDT) is a photochemical modality approved for cancer treatment. PDT has demonstrated efficacy in early stage lung cancer and esophageal cancer. The accumulation of photosensitizers in cancer cells is necessary to enhance the therapeutic benefits of PDT; however, photosensitizers have low uptake efficiency. To overcome this limitation, a drug delivery system, such as the hemagglutinating virus of Japan envelope (HVJ-E) vector, is required. In this study, the combination of PDT and HVJ-E was investigated for enhancing the efficacy of PDT. The photosensitizers that were evaluated included 5-aminolaevulinic acid (5-ALA), protoporphyrin IX (PPIX), and HVJ-PPIX. The uptake of the photosensitizers as increased twenty-fold with the addition of HVJ-E. The cytotoxicity of conventional 5-ALA was enhanced by the addition of HVJ-E vector. In conclusion, HVJ-E vector improved the uptake of photosensitizers and the PDT effect.

Assembly of catalase-based bioconjugates for enhanced anticancer efficiency of photodynamic therapy in vitro.

PubMed

Zhao, Jie; Fei, Jinbo; Du, Cuiling; Cui, Wei; Ma, Hongchao; Li, Junbai

2013-11-25

An oxygen generation core-shell structure uploading rose bengal has been fabricated by covalent assembly of catalase and alginate dialdehyde via Schiff's base. The composite can catalyze the decomposition of intracellular H2O2 to increase the concentration of O2, which effectively enhances the anticancer efficiency of photodynamic therapy in vitro.

Photodynamic therapy of vulvar intraepithelial neoplasia using 5-aminolevulinic acid.

PubMed

Hillemanns, P; Untch, M; Dannecker, C; Baumgartner, R; Stepp, H; Diebold, J; Weingandt, H; Pröve, F; Korell, M

2000-03-01

Photodynamic (PDT) therapy is a relatively new technique with unique properties that make it attractive for the local treatment of superficial epithelial disorders. The objective of this study was to investigate the clinical response of PDT with the photosensitizing agent 5-aminolevulinic acid (5-ALA) in patients with vulvar intraepithelial neoplasia (VIN) grades 1 to 3. Twenty-five patients with 111 lesions of VIN 1-3 were topically sensitized with 10 ml of a 20% solution of 5-ALA and treated with 57 cycles of laser light at 635 nm (100 J/cm(2)). Seventy (64%) of the 111 VIN lesions regressed after various PDT cycles. A complete response was achieved in 13 patients (52%) with 27 lesions. All patients with VIN 1 and mono- and bifocal VIN 2-3 showed complete clearance. However, a complete response could be achieved in only 4 (27%) of 15 women with multifocal VIN 2-3, whereas a partial response was noted in 9 of these patients with a total of 70 lesions, out of which 44 (63%) lesions disappeared. No response was seen in 2 patients with multifocal VIN 3. Histological assessment of the fluorescence-directed biopsies revealed that increased pigmentation and hyperkeratosis of the lesions were associated with low response rates. PDT using 5-ALA represents an alternative treatment modality for VIN which is easy to perform and has the advantage of minimal tissue destruction, low side effects and excellent cosmetic results. However, multifocal VIN disease with pigmented and hyperkeratinic lesions remains difficult to treat. Copyright 2000 Wiley-Liss, Inc.

In Vivo Study of Biological Effects of Photodynamic Therapy on Cervical Cancer

NASA Astrophysics Data System (ADS)

Marquez-Lemus, V. A.; Noguez-Juarez, B. M.; Solano-Rodriguez, L.; Perez-Zapata, A. J.; Schneider-Ehrenberg, O. P.; Graue-wiechers, F.; Ramón-Gallegos, E.

2005-01-01

In 1999, Ramon et al examined the effects of δ-aminolevulinic acid (δ-ALA) on two cervical cancer cell lines (HeLa and CaLo) and normal cervical cells. The results reported additionally support the proposal that Photodynamic Therapy (PDT) could be an effective tool for treatment of cervical cancer (CeCa) by protoporphyrin IX (PpIX) accumulation. This cancer is in México considered a problem of public health. In this project PDT was applied in a CeCa mouse model by implantation of HeLa cells in nu/nu mice, exposing it to δ-ALA to a dose that induces the greater concentration of PpIX by intratumoral and oral route, as well as the power and the number of optimal irradiations at 630 nm with a diode laser; verifying which of the used doses does not produce significant damage to the organs by means of histopatologic techniques: liver, spleen, brain and kidney, the determination of reactive substances to tiobarbituric acid (TBAR'S) and measured the amount of residual δ-ALA, the size of the tumor at the beginning and at the end of the application of the PDT. Results. The cervical cancer mouse model is developed by implantation of 1,5 million HeLa cells, appearing at 15 days. The dose of δ-ALA that induces the greater concentration of PpIX in the tumor by intratumoral route was 40 mg of δ-ALA/kg body weight and for oral route it was 20 mg of δ-ALA/kg body weight, both routes did not present significant damage in the organs and according to the Analysis of Bifactorial Variance for the doses of δ-ALA and the organs no difference exists (p > 0.05). The power of the used laser was 150 J/cm2 and 250 J/cm2, both applied by intratumoral and oral route after the δ-ALA administration. The greater diminution in the size of the tumor (53%) was by the δ-ALA oral route administration to a power of 150 J/cm2 with 5 irradiations in intervals of 48 h.

Silicon Phthalocyanines Axially Disubstituted with Erlotinib toward Small-Molecular-Target-Based Photodynamic Therapy.

PubMed

Chen, Juan-Juan; Huang, Yi-Zhen; Song, Mei-Ru; Zhang, Zhi-Hong; Xue, Jin-Ping

2017-09-21

Small-molecular-target-based photodynamic therapy-a promising targeted anticancer strategy-was developed by conjugating zinc(II) phthalocyanine with a small-molecular-target-based anticancer drug. To prevent self-aggregation and avoid problems of phthalocyanine isomerization, two silicon phthalocyanines di-substituted axially with erlotinib have been synthesized and fully characterized. These conjugates are present in monomeric form in various solvents as well as culture media. Cell-based experiments showed that these conjugates localize in lysosomes and mitochondria, while maintaining high photodynamic activities (IC 50 values as low as 8 nm under a light dose of 1.5 J cm -2 ). With erlotinib as the targeting moiety, two conjugates were found to exhibit high specificity for EGFR-overexpressing cancer cells. Various poly(ethylene glycol) (PEG) linker lengths were shown to have an effect on the photophysical/photochemical properties and on in vitro phototoxicity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Attempted photodynamic therapy against patagial squamous cell carcinoma in an African rose-ringed parakeet (Psittacula krameri).

PubMed

Suedmeyer, Wm Kirk; Henry, Carolyn; McCaw, Dudley; Boucher, Magalie

2007-12-01

A 5-yr-old female African rose-ringed parakeet (Psittacula krameri) presented with an ulcerated mass in the medial postpatagial area of the right wing. Biopsy specimens of the mass demonstrated a well-differentiated squamous cell carcinoma. Photodynamic therapy resulted in tumor cell necrosis and initial reduction in tumor burden, but complete remission was not achieved. Based on this and other avian cases, it appears that photodynamic therapy designed to eradicate squamous cell carcinoma in avian species using protocols modeled after canine, feline, and human photodynamic therapy protocols may not be useful. It is hypothesized that differences in light penetration, photosensitizing agent pharmacokinetics, and wound healing properties in avian species necessitate alteration of photodynamic therapy protocols if this treatment modality is to be effective in avian oncology.

Photodynamic Therapy for Cancer Cells Using a Flash Wave Light Xenon Lamp

NASA Astrophysics Data System (ADS)

Kimura, Makoto; Kashikura, Kasumi; Yokoi, Satomi; Koiwa, Yumiko; Tokuoka, Yoshikazu; Kawashima, Norimichi

We determined photodynamic therapy (PDT) efficacy using a flash wave (FW) and a continuous wave (CW) light, of which the fluence rate was 70 W/cm2, for murine thymic lymphoma cells (EL-4) cultivated in vitro. The irradiation frequency and the pulse width of the FW light were in the range of 1-32 Hz and less than one millisecond, respectively. 5-Aminolevulinic acid-induced protoporphyrin IX (ALA-PpIX) was used as a photosensitizer. When EL-4 with ALA administration was irradiated by the light for 4 h (irradiation fluence: 1.0J/cm2), the survival rate of EL-4 by the FW light was lower than that by the CW light, except for the FW light with irradiation frequency of 32 Hz, and decreased gradually with decreasing irradiation frequency. Moreover, the FW light, especially at lower irradiation frequency, was superior to the CW light for the generation of singlet oxygen in an aqueous PpIX solution. Therefore, thehigher PDT efficacy for EL-4 of the FW light would be caused by the greater generation of singlet oxygen in the cells.

Potential efficacy of a delta 5-aminolevulinic acid thermosetting gel formulation for use in photodynamic therapy of lesions of the gastrointestinal tract.

PubMed

Bourre, Ludovic; Thibaut, Sonia; Briffaud, Amelie; Lajat, Youenn; Patrice, Thierry

2002-02-01

Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA)-induced protoporphyrin IX may play a role in the treatment of dysplastic Barrett's oesophagus. An ALA thermosetting gel Pluronic F-127) was developed and evaluated in an in vivo mouse model for potential use in PDT of Barrett's mucosa. In vitro studies of the influence of Pluronic F-127 percentage on thermosetting gel temperature, followed by the influence of ALA concentration on thermosetting temperature and ALA-gel stability as a function of time or temperature were studied. In vivo relationships between ALA doses and fluorescence were studied to determine the optimal concentration. Fluorescence measurement in vivo showed that ALA concentration and time had a nonlinear influence on protoporphyrin IX synthesis. For ALA-gel applications longer than 30 min a plateau fluorescence was reached, the maximum fluorescence being obtained after 4 h whatever the time of contact. The maximum intensity (2824 counts s(-1)) was found with 40 mg mL(-1) ALA-gel, and fluorescence intensities differed with time, reaching a maximum after 3-4 h. ALA-Pluronic F-127 is a suitable formulation for treatment of Barrett's oesophagus, allowing easy application in liquid form at 4 degrees C and good adhesion in the oesophagus in gel form, with efficient diffusion of ALA into treated mucosa. Copyright 2002 Elsevier Science Ltd.

Photodynamic therapy for the treatment of folliculitis decalvans.

PubMed

Castaño-Suárez, Esther; Romero-Maté, Alberto; Arias-Palomo, Dolores; Borbujo, Jesús

2012-04-01

Folliculitis decalvans is a chronic form of deep folliculitis that occurs on the scalp as patches of scarring alopecia at the expanding margins of which are follicular pustules. Treatment of folliculitis decalvans is extremely difficult with a resultant poor prognosis. Photodynamic therapy has been reported to be effective in disorders as acne or folliculitis. We report one patient with folliculitis decalvans who was successfully treated with photodynamic therapy. © 2012 John Wiley & Sons A/S.

Aminolevulinic acid-photodynamic therapy combined with topically applied vascular disrupting agent vadimezan leads to enhanced antitumor responses.

PubMed

Marrero, Allison; Becker, Theresa; Sunar, Ulas; Morgan, Janet; Bellnier, David

2011-01-01

The tumor vascular-disrupting agent (VDA) vadimezan (5,6-dimethylxanthenone-4-acetic acid, DMXAA) has been shown to potentiate the antitumor activity of photodynamic therapy (PDT) using systemically administered photosensitizers. Here, we characterized the response of subcutaneous syngeneic Colon26 murine colon adenocarcinoma tumors to PDT using the locally applied photosensitizer precursor aminolevulinic acid (ALA) in combination with a topical formulation of vadimezan. Diffuse correlation spectroscopy (DCS), a noninvasive method for monitoring blood flow, was utilized to determine tumor vascular response to treatment. In addition, correlative CD31-immunohistochemistry to visualize endothelial damage, ELISA to measure induction of tumor necrosis factor-alpha (TNF-α) and tumor weight measurements were also examined in separate animals. In our previous work, DCS revealed a selective decrease in tumor blood flow over time following topical vadimezan. ALA-PDT treatment also induced a decrease in tumor blood flow. The onset of blood flow reduction was rapid in tumors treated with both ALA-PDT and vadimezan. CD31-immunostaining of tumor sections confirmed vascular damage following topical application of vadimezan. Tumor weight measurements revealed enhanced tumor growth inhibition with combination treatment compared with ALA-PDT or vadimezan treatment alone. In conclusion, vadimezan as a topical agent enhances treatment efficacy when combined with ALA-PDT. This combination could be useful in clinical applications. © 2011 The Authors. Photochemistry and Photobiology © 2011 The American Society of Photobiology.

Efficacy of ultra short sub-30 minute incubation of 5-aminolevulinic acid photodynamic therapy in vitro.

PubMed

Koo, Eugene; Austin, Evan; Mamalis, Andrew; Jagdeo, Jared

2017-08-01

The estimated incidence of cutaneous squamous cell carcinoma (SCC) is 700,000 cases per year. In the US, SCC incidence is highest among fair skinned adults older than 50 years of age. Thus, as the population ages, the reported number of SCCs will likely increase in the future. Photodynamic therapy (PDT) is an FDA approved therapy for treatment of actinic keratoses (AKs), a precursor to cutaneous SCC lesions. The FDA approved incubation time of the photosensitizing agent 5-aminolevulinic acid (ALA) is 14-18 hours. Recent studies have investigated short ALA incubation times of 1-3 hours with ALA and PDT demonstrating treatment success. Therefore, the question exists whether ALA incubation periods of less than 30 minutes are efficacious. Herein, we evaluate the efficacy of short ALA incubation periods by measuring apoptosis after 10, 15, and 20 minutes of ALA incubation. AG13145 normal human dermal fibroblasts HDFs were incubated with 10, 15, or 20 minute of ALA at various concentrations (0, 0.05, 0.075, 0.1, 0.25, 0.375, 0.5, 1, and 2 mM). After ALA incubation, samples were treated with 1,000 seconds (16 minutes 40 seconds) of Blu-U fluorescent blue light (417 ± 5 nm) for a fluence of 10 J/cm 2 . Immediately following treatment with blue light, samples were collected and stained for apoptosis and necrosis with annexin-V and 7-aminoactinomycin D (7-AAD), and then analyzed by flow cytometry. HDFs incubated with ALA for 10 minute at 36 °C followed by 10 J/cm 2 of blue light had no statistically significant changes in apoptosis. HDFs incubated with ALA for 15 or 20 minutes at 36 °C followed by 10 J/cm 2 of blue light had statistically significant increases in the percentages of cells positive for apoptosis in the 0.5, 1.0, and 2.0 mM ALA doses (P < 0.05). We found that incubation of ALA for at least 15 minutes followed by 10 J/cm 2 of blue light resulted in a statistically significant increase in apoptosis. Lasers Surg. Med. 49

The natural flavonoid silybin improves the response to Photodynamic Therapy of bladder cancer cells.

PubMed

Gándara, L; Sandes, E; Di Venosa, G; Prack Mc Cormick, B; Rodriguez, L; Mamone, L; Batlle, A; Eiján, A M; Casas, A

2014-04-05

Photodynamic Therapy (PDT) is an anticancer treatment based on photosensitisation of malignant cells. The precursor of the photosensitiser Protoporphyrin IX, 5-aminolevulinic acid (ALA), has been used for PDT of bladder cancer. Silybin is a flavonoid extracted from Silybum marianum, and it has been reported to increase the efficacy of several anticancer treatments. In the present work, we evaluated the cytotoxicity of the combination of ALA-PDT and silybin in the T24 and MB49 bladder cancer cell lines. MB49 cells were more sensitive to PDT damage, which was correlated with a higher Protoporphyrin IX production from ALA. Employing lethal light doses 50% (LD50) and 75% (LD75) and additional silybin treatment, there was a further increase of toxicity driven by PDT in both cell lines. Using the Chou-Talalay model for drug combination derived from the mass-action law principle, it was possible to identify the effect of the combination as synergic when using LD75, whilst the use of LD50 led to an additive effect on MB49 cells. On the other hand, the drug combination turned out to be nearly additive on T24 cells. Apoptotic cell death is involved both in silybin and PDT cytotoxicity in the MB49 line but there is no apparent correlation with the additive or synergic effect observed on cell viability. On the other hand, we found an enhancement of the PDT-driven impairment of cell migration on both cell lines as a consequence of silybin treatment. Overall, our results suggest that the combination of silybin and ALA-PDT would increase PDT outcome, leading to additive or synergistic effects and possibly impairing the occurrence of metastases. Copyright © 2014 Elsevier B.V. All rights reserved.

Role of 5-aminolevulinic acid-conjugated gold nanoparticles for photodynamic therapy of cancer

NASA Astrophysics Data System (ADS)

Zhang, Zhenxi; Wang, Sijia; Xu, Hao; Wang, Bo; Yao, Cuiping

2015-05-01

There are three possible mechanisms for 5-aminolevulinic acid (5-ALA) conjugated gold nanoparticles (GNPs) through electrostatic bonding for photodynamic therapy (PDT) of cancer: GNPs delivery function, singlet oxygen generation (SOG) by GNPs irradiated by light, and surface resonance enhancement (SRE) of SOG. Figuring out the exact mechanism is important for further clinical treatment. 5-ALA-GNPs and human chronic myeloid leukemia K562 cells were used to study delivery function and SOG by GNPs. The SRE of SOG enabled by GNPs was explored by protoporphyrin IX (PpIX)-GNPs conjugate through electrostatic bonding. Cell experiments show that the GNPs can improve the efficiency of PDT, which is due to the vehicle effect of GNPs. PpIX-GNPs conjugate experiments demonstrated that SOG can be improved about 2.5 times over PpIX alone. The experiments and theoretical results show that the local field enhancement (LFE) via localized surface plasmon resonance (LSPR) of GNPs is the major role; the LFE was dependent on the irradiation wavelength and the GNP's size. The LFE increased with an increase of the GNP size (2R ≤50 nm). However, the LSPR function of the GNPs was not found in cell experiments. Our study shows that in 5-ALA-conjugated GNPs PDT, the delivery function of GNPs is the major role.

An In Vitro Model to Study the Effect of 5-Aminolevulinic Acid-mediated Photodynamic Therapy on Staphylococcus aureus Biofilm.

PubMed

Zhao, Ke-Qing; Wu, Yang; Yi, Yu-Xi; Feng, Si-Jia; Wei, Ruo-Yan; Ma, Ying; Zheng, Chun-Quan; Qu, Di

2018-04-16

Staphylococcus aureus (S. aureus) is a common human pathogen, which causes pyogenic and systemic infections. S. aureus infections are difficult to eradicate not only due to the emergence of antibiotic-resistant strains but also its ability to form biofilms. Recently, photodynamic therapy (PDT) has been indicated as one of the potential treatments for controlling biofilm infections. However, further studies are required to improve our knowledge of its effect on bacterial biofilms, as well as the underlying mechanisms. This manuscript describes an in vitro model of PDT with 5-aminolevulinic acid (5-ALA), a precursor of the actual photosensitizer, protoporphyrin IX (PpIX). Briefly, mature S. aureus biofilms were incubated with ALA and then exposed to light. Subsequently, the antibacterial effect of ALA-PDT on S. aureus biofilm was quantified by calculating the colony forming units (CFUs) and visualized by viability fluorescent staining via confocal laser scanning microscopy (CLSM). Representative results demonstrated a strong antibacterial effect of ALA-PDT on S. aureus biofilms. This protocol is simple and can be used to develop an in vitro model to study the treatment of S. aureus biofilms with ALA-PDT. In the future, it could also be referenced in PDT studies utilizing other photosensitizers for different bacterial strains with minimal adjustments.

Modification of the photodynamic action of delta-aminolaevulinic acid (ALA) on rat pancreatoma cells by mitochondrial benzodiazepine receptor ligands.

PubMed Central

Ratcliffe, S. L.; Matthews, E. K.

1995-01-01

We have shown that addition of exogenous delta-aminolaevulinic acid (ALA) to rat pancreatoma AR4-2J cells in culture leads to the increased production of porphobilinogen (PBG) and the accumulation of photoactive protoporphyrin IX (PPix) in these cells. Exposure to light (lambda > 400 nm) at an intensity of 0.2 mW cm-2 for 8 min resulted in an ALA dose-dependent cytolysis of the cells, with an EC50 of 6.6 +/- 0.7 microM. This cytolytic effect was light intensity dependent, with greater cell destruction after exposure to light at an intensity of 0.47 mW cm-2 than at 0.2 mW cm-2; it was also dependent on the duration of illumination, cell survival decreasing with increasing illumination times. The photodestruction of the AR4-2J cells following exposure to ALA can be attributed to the production of endogenous PPix, a photoactive porphyrin that we have shown to generate singlet oxygen upon illumination, whereas ALA itself does not. Further investigation of the molecular mechanisms underlying the photodynamic action of ALA demonstrated the involvement of the mitochondrial (peripheral) benzodiazepine receptor (MBR), a high-affinity recognition site for dicarboxylic porphyrins, and especially PPix. The centrally acting benzodiazepine compounds clonazepam and flumazenil, which have negligible affinities for the MBR, had no effect on ALA-mediated phototoxicity. In contrast, both the isoquinoline carboxamide PK11195 and the benzodiazepine Ro 5-4864 ligands, displaying a high affinity for the MBR, did affect ALA-mediated phototoxicity, each markedly increasing the EC50 for cell photodestruction and thus exerting a photoprotective effect. It is concluded that the MBR may play an important role in the expression of ALA-mediated PPix phototoxicity and that MBR ligands, by diminishing the actions of endogenous PPix, have the potential to rescue cells from porphyrin-induced photolysis. PMID:7841044

Topical methotrexate pretreatment enhances the therapeutic effect of topical 5-aminolevulinic acid-mediated photodynamic therapy on hamster buccal pouch precancers.

PubMed

Yang, Deng-Fu; Lee, Jeng-Woei; Chen, Hsin-Ming; Hsu, Yih-Chih

2014-09-01

Topical 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) is effective for treatment of human oral precancerous lesions. This animal study aimed to assess whether topical methotrexate (MTX) pretreatment could enhance the therapeutic effect of topical ALA-PDT on hamster buccal pouch precancerous lesions. Twenty hamster buccal pouch precancerous lesions were treated with either topical ALA-PDT with topical MTX pretreatment (topical MTX-ALA-PDT group, n = 10) or topical ALA-PDT alone (topical ALA-PDT group, n = 10). The intracellular protoporphyrin IX (PpIX) level in another 12 precancerous lesions (n = 6 for either the topical MTX-ALA or topical ALA group) was monitored by fluorescence spectroscopy. The intracellular PpIX reached its peak level in precancerous lesions 6.5 hours and 2.5 hours after topical ALA application for the topical MTX-ALA group (5.63-fold higher in the lesion than in the normal mucosa) and topical ALA group (2.42-fold higher in the lesion than in the normal mucosa), respectively. The complete response rate of precancerous lesions was 80% for the topical MTX-ALA-PDT group and 70% for the topical ALA-PDT group. In addition, the topical MTX-ALA-PDT group required a significantly lower mean treatment number (2.1 ± 0.6) to achieve complete response than the topical ALA-PDT group (4.4 ± 1.3, p < 0.001)). Moreover, the topical MTX-ALA-PDT group had a lower recurrence rate (12.5%) than the topical ALA-PDT group (28.6%). We conclude that topical MTX-pretreatment can increase intracellular PpIX production in hamster buccal pouch precancerous lesions and significantly improves the outcomes of the precancerous lesions treated with topical ALA-PDT. Copyright © 2014. Published by Elsevier B.V.

Can red-light 5-aminolevulinic photodynamic therapy cure port wine stains on comb animal model?

PubMed

Lai, Yongxian; Zhang, Haiyan; Wei, Minglei; Ji, Jie; Shi, Lei; Wang, Peiru; Wang, Bo; Huang, Zheng; Wang, Xiuli

2018-06-01

To study the curative effect of red-light 5-Aminolevulinic photodynamic therapy(ALA-PDT) to port wine stains(PWS) on comb animal model. 160 male cocks were randomly divided into 16 groups. The ALA only group was given ALA only topical or systemic application. Light only groups were only given 630 nm red light irradiation with different light density. ALA-PDT groups were given red light after the application of topical or systemic ALA. PDL group was given PDL irradiation. The distribution of fluorescence in tissue after topical or systemic application of ALA was detected. The morphological changes, the pathological changes and the capillary reduction rate of the comb were observed after treatment for 0, 1, 3, 5, 7, 14 days. The PpIX fluorescence generated after topical and systemic application of ALA. In the topical ALA-PDT group at low light density 80 J/cm 2 , the morphology and the histopathology had no obvious change. While under 160 J/cm 2 and 200 J/cm 2 light density, severe erosion and thick scab appeared. The histopathology showed epidermal necrosis and loss. The immunohistochemistry showed that there was no significant change in the number of capillaries under different light density (P > 0.05). In the systemic ALA-PDT group under low light density 80 J/cm 2 , only partial erosion and thin scab was observed on the treatment side. With the increase of light density, thick charred crust and even scar was observed. The histopathology showed that there were different degrees of damage to dermal and epidermal tissues. And the immunohistochemistry showed the capillary reduced significantly in the treatment side (P < 0.01). In control group, the comb is ruddy and plump. These results suggest that either topical or systemic red-light ALA-PDT is not suitable treatment methods for PWS. Copyright © 2018 Elsevier B.V. All rights reserved.

Nontumor photodynamic therapy

NASA Astrophysics Data System (ADS)

van den Bergh, Hubert

1997-12-01

Photodynamic therapy (PDT) has become an approved treatment for different types of cancer in many countries over the last few years. As an example one might mention PDT of the early stages of bronchial or esophageal cancer which have been treated with only about 20% recurrence being observed over several years of follow-up. The low degree of invasion of PDT, as compared to most alternative treatments as well as minimal sided effects, and good repeatability, all speak for this treatment modality. Improved and cheap screening procedures, that are now being developed for the early stage disease, will lead to a more frequent application of PDT for these indications. Detailed studies of PDT showed that certain dyes, after systematic or topical application, could be taken up more in neoplastic tissue as compared to the surrounding normal tissue in the clinical context, thus leading to 'selective' or at least partially selective destruction of the tumor following light application. This selectivity of uptake of certain compounds in hyperproliferative tissue, as well as the observation that PDT can lead to blood vessel stasis, suggested that photodynamic therapy might be worth trying in non-tumor disease. Some of the diseases associated with hyperproliferation and/or neovascularization which are being considered for PDT are listed in table I.

Interstitial photodynamic therapy of canine prostate with meso-tetra-(m-hydroxyphenyl) chlorin and 5-aminolevulinic acid: a preliminary study

NASA Astrophysics Data System (ADS)

Chang, Shi-Chung; Buonaccorsi, Giovanni A.; MacRobert, Alexander J.; Bown, Stephen G.

1996-01-01

Photodynamic therapy (PDT) is proved to have potential for managing various malignancies. We investigated tissue biodistribution and photodynamic effects on a canine model in vivo using second generation photosensitizers, meso-tetra(m-hydroxyphenyl)chlorin (mTHPC) and 5-aminolaevulinic acid (ALA) to evaluate the feasibility and possible future application of PDT on the prostate. Using fluorescence microscopy, the optimal sensitization time of the prostate was between 24 - 72 hours with mTHPC and, 3 hours with ALA. After optimum time of sensitization, prostates of mature beagle were treated with laser at various sites by placing fiber interstitially under the guidance of transrectal ultrasound. The light dose for each treatment site was 100 J (100 mW for 1,000 seconds at the wavelength of 650 and 630 nm, respectively). With mTHPC, single laser fiber was able to induce organ confined PDT lesion as large as 20 by 18 by 18 mm in size. However, the PDT lesion with ALA was negligible 3 days after treatment. Physical distress manifested as urinary retention, poor appetite and body weigh loss, was more prominent with increasing number of treatment sites as a result of extensive prostatic swelling and urethral damages. However, these problems usually alleviated spontaneously 7 to 10 days after PDT. The characteristic histological changes were hemorrhagic necrosis and glandular destruction with preservation of interlobular collagen fibers. Urethral damage seen at the early stage healed by regeneration of urothelium in 4 weeks. We conclude that interstitial PDT with mTHPC is technically possible to produce extensive glandular necrosis in the normal prostate which heals safely and does not change the prostatic architecture. ALA, although it seems promising for bladder tumors, is much less effective than mTHPC on the prostate. With mTHPC, it might have the potential for treating prostate cancers localized in the periphery of the gland.

Photodynamic therapy using hemagglutinating virus of Japan envelope (HVJ-E): a novel therapeutic approach for the treatment of hormone antagonistic prostate cancer

NASA Astrophysics Data System (ADS)

Inai, Mizuho; Yamauchi, Masaya; Honda, Norihiro; Hazama, Hisanao; Tachikawa, Shoji; Nakamura, Hiroyuki; Nishida, Tomoki; Yasuda, Hidehiro; Kaneda, Yasufumi; Awazu, Kunio

2015-03-01

Traditional treatment options for prostate cancer are insufficient to cure advanced drug-resistant prostate cancer. Thus, as an alternative form of cancer therapy, photodynamic therapy (PDT) has become the main subject of intense investigation as a possible treatment modality. In this study, ultraviolet-inactivated viral vector, called hemagglutinating virus of Japan envelope (HVJ-E) was utilized to establish an effective delivery system for photosensitizer. Lipidated protoporphyrin IX (PpIX lipid) was inserted in HVJ-E by centrifugation to create a new drug delivering system that allows selective accumulation of photosensitizers in cancer cells. To study in vitro drug release mechanism of porphyrus envelope, the ultra-high voltage electron microscope tomography was applied. Next, to evaluate the photodynamic efficiency of porphyrus envelope for hormone antagonistic prostate cancer cells (PC-3), uptake of porphyrus envelope derived PpIX lipid and PpIX induced from exogenously administered precursor of 5-aminolevulinic acid hydrochloride (5-ALA) were compared by measuring fluorescence intensity of PpIX. Finally, to evaluate the efficacy of porphyrus envelope-PDT, laser light at a wavelength of 405 nm was irradiated to PC-3 cells. As a result, incorporation of porphyrus envelope-derived PpIX lipid occurred via membrane fusion, giving the highest fluorescence intensity when compared to 5-ALA-induced PpIX. Also, results from PDT experiment revealed the 28.6 × 103-fold and 206-fold increase in therapeutic efficacy when compared to those of PDT using 5-ALA induced PpIX and PpIX lipid, respectively. Our findings suggest how porphyrus envelope can induce efficient accumulation of PpIX lipid, which can enhance the therapeutic efficacy of PDT against hormone antagonistic prostate cancer.

Photodynamic therapy toward selective endometrial ablation

NASA Astrophysics Data System (ADS)

Tadir, Yona; Tromberg, Bruce J.; Krasieva, Tatiana B.; Berns, Michael W.

1993-05-01

Potential applications of photodynamic therapy for endometrial disease are discussed. Experimental models that may lead to diagnosis and treatment of endometriosis as well as selective endometrial ablation are summarized.

The application of hyaluronic acid-derivatized carbon nanotubes in hematoporphyrin monomethyl ether-based photodynamic therapy for in vivo and in vitro cancer treatment

PubMed Central

Shi, Jinjin; Ma, Rourou; Wang, Lei; Zhang, Jing; Liu, Ruiyuan; Li, Lulu; Liu, Yan; Hou, Lin; Yu, Xiaoyuan; Gao, Jun; Zhang, Zhenzhong

2013-01-01

Carbon nanotubes (CNTs) have shown great potential in both photothermal therapy and drug delivery. In this study, a CNT derivative, hyaluronic acid-derivatized CNTs (HA-CNTs) with high aqueous solubility, neutral pH, and tumor-targeting activity, were synthesized and characterized, and then a new photodynamic therapy agent, hematoporphyrin monomethyl ether (HMME), was adsorbed onto the functionalized CNTs to develop HMME-HA-CNTs. Tumor growth inhibition was investigated both in vivo and in vitro by a combination of photothermal therapy and photodynamic therapy using HMME-HA-CNTs. The ability of HMME-HA-CNT nanoparticles to combine local specific photodynamic therapy with external near-infrared photothermal therapy significantly improved the therapeutic efficacy of cancer treatment. Compared with photodynamic therapy or photothermal therapy alone, the combined treatment demonstrated a synergistic effect, resulting in higher therapeutic efficacy without obvious toxic effects to normal organs. Overall, it was demonstrated that HMME-HA-CNTs could be successfully applied to photodynamic therapy and photothermal therapy simultaneously in future tumor therapy. PMID:23843694

Low-Dose Topical 5-Aminolevulinic Acid Photodynamic Therapy in the Treatment of Different Severity of Acne Vulgaris.

PubMed

Tao, Shi-Qin; Li, Fei; Cao, Lei; Xia, Ru-Shan; Fan, Hua; Fan, Ying; Sun, Hui; Jing, Cheng; Yang, Li-Jia

2015-12-01

The objective of this article is to investigate the effectiveness and safety of photodynamic therapy (PDT) with 3.6 % topical aminolevulinic acid (ALA) and a short incubation time with red light in moderate to severe acne. One hundred and thirty-six patients with moderate to severe acne were treated with 3.6 % topical ALA-PDT for three sessions with an interval of 2 weeks. Patients were evaluated for efficacy and safety on week 2, 4, 6, 8, and 12 after the initial treatment. Most patients showed apparent clearance of acne lesions at the treated site after three sessions. The effective treatment rates were increased after the multiple therapies. The clinical outcomes are the best at 4 weeks after the final treatment. The total effectiveness rate and cure rate of the low-dose ALA-PDT procedure is 92.65 and 47.06 %, respectively. Thirty-one patients and nineteen patients showed apparent exacerbation of acne lesions before the 2nd and 3rd treatment, respectively, but all of them showed good or excellent improvement after a three-course treatment. A few patients showed mild relapse including papules and comedos at 8 weeks after the final treatment. No significant differences are found in the effects of different acne severity and different genders. Adverse reactions are mild and transient. A 3.6 % topical ALA-PDT with a short time incubation with red light is a simple and an effective treatment option for moderate to severe acne with mild side effects in Chinese people.

The Antimicrobial Photodynamic Therapy in the Treatment of Peri-Implantitis

PubMed Central

Libotte, Fabrizio; Sabatini, Silvia; Grassi, Felice Roberto

2016-01-01

Introduction. The aim of this study is to demonstrate the effectiveness of addition of the antimicrobial photodynamic therapy to the conventional approach in the treatment of peri-implantitis. Materials and Methods. Forty patients were randomly assigned to test or control groups. Patients were assessed at baseline and at six (T1), twelve (T2), and twenty-four (T3) weeks recording plaque index (PlI), probing pocket depth (PPD), and bleeding on probing (BOP); control group received conventional periodontal therapy, while test group received photodynamic therapy in addition to it. Result. Test group showed a 70% reduction in the plaque index values and a 60% reduction in PD values compared to the baseline. BOP and suppuration were not detectable. Control group showed a significative reduction in plaque index and PD. Discussion. Laser therapy has some advantages in comparison to traditional therapy, with faster and greater healing of the wound. Conclusion. Test group showed after 24 weeks a better value in terms of PPD, BOP, and PlI, with an average pocket depth value of 2 mm, if compared with control group (3 mm). Our results suggest that antimicrobial photodynamic therapy with diode laser and phenothiazine chloride represents a reliable adjunctive treatment to conventional therapy. Photodynamic therapy should, however, be considered a coadjuvant in the treatment of peri-implantitis associated with mechanical (scaling) and surgical (grafts) treatments. PMID:27429618

T-Opt: A 3D Monte Carlo simulation for light delivery design in photodynamic therapy (Conference Presentation)

NASA Astrophysics Data System (ADS)

Honda, Norihiro; Hazama, Hisanao; Awazu, Kunio

2017-02-01

The interstitial photodynamic therapy (iPDT) with 5-aminolevulinic acid (5-ALA) is a safe and feasible treatment modality of malignant glioblastoma. In order to cover the tumour volume, the exact position of the light diffusers within the lesion is needed to decide precisely. The aim of this study is the development of evaluation method of treatment volume with 3D Monte Carlo simulation for iPDT using 5-ALA. Monte Carlo simulations of fluence rate were performed using the optical properties of the brain tissue infiltrated by tumor cells and normal tissue. 3-D Monte Carlo simulation was used to calculate the position of the light diffusers within the lesion and light transport. The fluence rate near the diffuser was maximum and decreased exponentially with distance. The simulation can calculate the amount of singlet oxygen generated by PDT. In order to increase the accuracy of simulation results, the parameter for simulation includes the quantum yield of singlet oxygen generation, the accumulated concentration of photosensitizer within tissue, fluence rate, molar extinction coefficient at the wavelength of excitation light. The simulation is useful for evaluation of treatment region of iPDT with 5-ALA.

Photodynamic therapy influence on anti-cancer immunity

NASA Astrophysics Data System (ADS)

Isaeva, O. G.; Osipov, V. A.

2010-02-01

The system of partial differential equations describing tumor-immune dynamics with angiogenesis taken into account is presented. For spatially homogeneous case, the steady state analysis of the model is carried out. The effects of single photodynamic impact are numerically simulated. In the case of strong immune response we found that the photodynamic therapy (PDT) gives rise to the substantial shrinkage of tumor size which is accompanied by the increase of IL-2 concentration. On the contrary, the photodynamic stimulation of weak immune response is shown to be insufficient to reduce the tumor. These findings indicate the important role of anti-cancer immune response in the long-term tumor control after PDT.

Photodynamic therapy influence on anti-cancer immunity

NASA Astrophysics Data System (ADS)

Isaeva, O. G.; Osipov, V. A.

2009-10-01

The system of partial differential equations describing tumor-immune dynamics with angiogenesis taken into account is presented. For spatially homogeneous case, the steady state analysis of the model is carried out. The effects of single photodynamic impact are numerically simulated. In the case of strong immune response we found that the photodynamic therapy (PDT) gives rise to the substantial shrinkage of tumor size which is accompanied by the increase of IL-2 concentration. On the contrary, the photodynamic stimulation of weak immune response is shown to be insufficient to reduce the tumor. These findings indicate the important role of anti-cancer immune response in the long-term tumor control after PDT.

Photodynamic therapy for actinic cheilitis: a systematic review.

PubMed

Yazdani Abyaneh, Mohammad-Ali; Falto-Aizpurua, Leyre; Griffith, Robert D; Nouri, Keyvan

2015-02-01

Actinic cheilitis (AC) is a premalignant lesion of the lips that can progress to squamous cell carcinoma and metastasize. Actinic cheilitis is difficult to treat because surgical treatments have significant adverse effects whereas less invasive procedures have uncertain efficacy. Photodynamic therapy (PDT) may offer a noninvasive yet effective treatment option for AC. To systematically review the safety and efficacy of PDT for AC. The terms "photodynamic," "actinic," "solar," "cheilitis," and "cheilosis" were used in combinations to search the PubMed database. Studies were considered for inclusion based on eligibility criteria, and specific data were extracted from all studies. The authors identified 15 eligible case series encompassing a total of 242 treated subjects. Among studies that evaluated subjects for complete clinical response, 139 of 223 subjects (62%) showed complete response at final follow-ups ranging from 3 to 30 months. Among studies that evaluated subjects for histological outcome, 57 of 121 subjects (47%) demonstrated histological cure at final follow-ups ranging from 1.5 to 18 months. Cosmetic outcomes were good to excellent in the majority of subjects, and adverse events were well tolerated. Photodynamic therapy is safe and has the potential to clinically and histologically treat AC, with a need for future randomized controlled trials.

Photodynamic therapy of cervical intraepithelial neoplasia

NASA Astrophysics Data System (ADS)

Inada, Natalia M.; Lombardi, Welington; Leite, Marieli F. M.; Trujillo, Jose R.; Kurachi, Cristina; Bagnato, Vanderlei S.

2014-03-01

Photodynamic therapy (PDT) is a technique that has been used for the treatment of tumors, especially in Gynecology. The photodynamic reaction is based on the production of reactive oxygen species after the activation of a photosensitizer. Advantages of the PDT in comparison to the surgical resection are: ambulatory treatment and tissue recovery highly satisfactory, through a non-invasive procedure. The cervical intraepithelial neoplasia (CIN) grades I and II presents potential indications for PDT. The aim of the proposed study is to evaluate the safety and efficacy of the PDT for the diagnostics and treatment of CIN I and II. The equipment and the photosensitizer are produced in Brazil with a representative low cost. It is possible to visualize the fluorescence of the cervix and to treat the lesions, without side effects. The proposed clinical protocol shows great potential to become a public health technique.

Molecular imaging of photodynamic therapy

NASA Astrophysics Data System (ADS)

Chang, Sung K.; Errabelli, Divya; Rizvi, Imran; Solban, Nicolas; O'Riordan, Katherine; Hasan, Tayyaba

2006-02-01

Recent advances in light sources, detectors and other optical imaging technologies coupled with the development of novel optical contrast agents have enabled real-time, high resolution, in vivo monitoring of molecular targets. Noninvasive monitoring of molecular targets is particularly relevant to photodynamic therapy (PDT), including the delivery of photosensitizer in the treatment site and monitoring of molecular and physiological changes following treatment. Our lab has developed optical imaging technologies to investigate these various aspects of photodynamic therapy (PDT). We used a laser scanning confocal microscope to monitor the pharmacokinetics of various photosensitizers in in vitro as well as ex vivo samples, and developed an intravital fluorescence microscope to monitor photosensitizer delivery in vivo in small animals. A molecular specific contrast agent that targets the vascular endothelial growth factor (VEGF) was developed to monitor the changes in the protein expression following PDT. We were then able to study the physiological changes due to post-treatment VEGF upregulation by quantifying vascular permeability with in vivo imaging.

Virus-Based Cancer Therapeutics for Targeted Photodynamic Therapy.

PubMed

Cao, Binrui; Xu, Hong; Yang, Mingying; Mao, Chuanbin

2018-01-01

Cancer photodynamic therapy (PDT) involves the absorption of light by photosensitizers (PSs) to generate cytotoxic singlet oxygen for killing cancer cells. The success of this method is usually limited by the lack of selective accumulation of the PS at cancer cells. Bioengineered viruses with cancer cell-targeting peptides fused on their surfaces are great drug carriers that can guide the PS to cancer cells for targeted cancer treatment. Here, we use cell-targeting fd bacteriophages (phages) as an example to describe how to chemically conjugate PSs (e.g., pyropheophorbide-a (PPa)) onto a phage particle to achieve targeted PDT.

Electrochemical microsensor system for cancer research on photodynamic therapy in vitro

NASA Astrophysics Data System (ADS)

Marzioch, J.; Kieninger, J.; Sandvik, J. A.; Pettersen, E. O.; Peng, Q.; Urban, G.

2016-10-01

An electrochemical microsensor system to investigate photodynamic therapy of cancer cells in vitro was developed and applied to monitor the cellular respiration during and after photodynamic therapy. The redox activity and therefore influence of the photodynamic drug on the sensor performance was investigated by electrochemical characterization. It was shown, that appropriate operation conditions avoid cross-sensitivity of the sensors to the drug itself. The presented system features a cell culture chamber equipped with microsensors and a laser source to photodynamically treat the cells while simultaneous monitoring of metabolic parameter in situ. Additionally, the optical setup allows to read back fluorescence signals from the photosensitizer itself or other marker molecules parallel to the microsensor readings.

Noninvasive extramammary Paget's disease treated with photodynamic therapy: case series from the Roswell Park Cancer Institute.

PubMed

Housel, Joseph P; Izikson, Leonid; Zeitouni, Nathalie C

2010-11-01

Extramammary Paget's disease (EMPD) is a rare low-grade cutaneous malignancy that affects apocrine gland-bearing areas and most commonly occurs on the perineal skin. Photodynamic therapy (PDT) may represent a useful treatment option for extensive, noninvasive EMPD, alone or as part of multimodal therapy. To analyze the clinical outcomes of PDT for noninvasive EMPD with topical aminolevulinic acid (ALA) or intravenous porfimer sodium as photosensitizing agents and argon laser as the photoactivator. Retrospective case series of patients with noninvasive EMPD treated at Roswell Park Cancer Institute with PDT from April 20, 1995, to December 4, 2008. Identified patients included five men and three women aged 50 to 80 (mean age 67) with a total of 24 distinct lesions of noninvasive EMPD without distant metastases. Four patients received topical ALA only as a photosensitizer, three received intravenous porfimer sodium only, and one received both. All patients were treated using a 632.8-nm argon-pumped dye laser, and some were also treated using a red lamp (590-729 nm). Seven of nine lesions (78%) treated with PDT using intravenous porfimer sodium showed a complete response (CR) and were disease free at 12 to 96 months. Eight of 16 lesions (50%) treated with PDT using topical ALA showed a CR, and 38% were disease free at 9 to 88 months. None of the treated patients developed any serious cosmetic or functional impairments, such as loss of sphincter control or dysesthesias. PDT with intravenous porfimer sodium or topical ALA and argon laser may represent a useful, surgery-sparing therapeutic option for management of noninvasive EMPD in selected patients. Prospective, randomized clinical trials are necessary to compare the effectiveness of PDT with that of surgery for noninvasive EMPD. © 2010 by the American Society for Dermatologic Surgery, Inc.

Treatment of canine hemangiopericytomas with photodynamic therapy.

PubMed

McCaw, D L; Payne, J T; Pope, E R; West, M K; Tompson, R V; Tate, D

2001-01-01

Canine hemangiopericytomas are a commonly occurring neoplasm with a clinical course of recurrence after surgical removal. This study sought to evaluate Photochlor (HPPH) photodynamic therapy (HPPH-PDT) as an adjuvant therapy to prevent recurrence of tumor after surgical removal. Sixteen dogs with naturally occurring hemangiopericytomas were treated with surgical removal of the tumor followed by PDT using Photochlor as the photosensitizer. Photochlor was injected intravenously at a dose of 0.3 mg/kg. Forty-eight hours later the treatment consisted of surgical removal of the tumor followed by HPPH-PDT. Nine dogs (56%) had recurrence of tumor from 2 to 29 (median 9) months after treatment. These results are comparable or not as good as other forms of therapy. Photochlor photodynamic therapy applied after surgery appears to have no advantage over other forms of therapy in regards to preventing recurrence. Delayed wound healing and infections are problematic and make HPPH-PDT an undesirable addition to surgery for the treatment of this tumor type. Copyright 2001 Wiley-Liss, Inc.

Combination of photodynamic therapy and immunotherapy - evolving role in dermatology

NASA Astrophysics Data System (ADS)

Wang, Xiu-Li; Wang, Hong-Wei; Huang, Zheng

2008-02-01

Photodynamic therapy (PDT) is a promising treatment modality. It offers alternative options in the treatment of cancer and vascular diseases. In cancer treatment, PDT has been used primarily for localized superficial or endoluminal malignant and premalignant conditions. More recently, its application has also been expanded to solid tumors. However, its antitumor efficacy remains debatable and its acceptance still variable. Pre-clinical studies demonstrate that, in addition to the primary local cytotoxicity, PDT might induce secondary host immune responses, which may further enhance PDT's therapeutic effects on primary tumor as well as metastasis. Therefore, PDT-induced local and systemic antitumor immune response might play an important role in successful control of malignant diseases. Furthermore, PDT's antitumor efficacy might also be enhanced through an effective immunoadjuvant or immunomodulator. Our recent clinical data also indicate that improved clinical outcomes can be obtained by a combination of PDT and immunomodulation therapy for the treatment of pre-malignant skin diseases. For instance, the combination of topical ALA-PDT and Imiquimod is effective for the treatment of genital bowenoid papulosis. This presentation will also report our preliminary data in developing combination approaches of PDT and immunotherapy for actinic keratosis (AK), basal cell carcinomas (BCCs) and Bowen's disease.

5-ALA photopreparation using pulsed NIR enhances skin fluorescence via temperature-independent cell signaling pathways

NASA Astrophysics Data System (ADS)

Barolet, Augustin C.; Cormack, Gregory; Barolet, Daniel

2018-02-01

The effect of near infrared light (940 nm) on the conversion of 5-aminolevulinic acid (5-ALA) to PpIX, a compound involved in photodynamic therapy (PDT), was examined. The back skin of three test subjects was irradiated with continuous wavelength and pulsed infrared light at 940 nm. These irradiations took place 50-53, 24-29, and 8-14 hours prior to the application of the 5-ALA. After a three-hour incubation period with 5-ALA, a FluoDerm™device was used to measure the fluorescence of the skin (emitting wavelength: 400-420 nm; measuring excitation wavelength: 610-720 nm), a direct indication of the activity of 5-ALA. 5-ALA must penetrate the skin and then be converted to PpIX before any fluorescence increase can be observed. Results: For two patients (one was disqualified), the continuous wavelength, 50 hour pre-irradiation condition, the FluoDerm readings showed a 19 to 23% increase in fluorescence (p = 0.05) compared to the no-irradiation, 5-ALA only control.

Photodynamic Therapy with Hypericin Improved by Targeting HSP90 Associated Proteins

PubMed Central

Solár, Peter; Chytilová, Mária; Solárová, Zuzana; Mojžiš, Ján; Ferenc, Peter; Fedoročko, Peter

2011-01-01

In this study we have focused on the response of SKBR-3 cells to both single 17-DMAG treatment as well as its combination with photodynamic therapy with hypericin. Low concentrations of 17-DMAG without any effect on survival of SKBR-3 cells significantly reduced metabolic activity, viability and cell number when combined with photodynamic therapy with hypericin. Moreover, IC10 concentation of 17-DMAG resulted in significant increase of SKBR-3 cells in G1 phase of the cell cycle, followed by an increase of cells in G2 phase when combined with photodynamic therapy. Furthermore, 17-DMAG already decreased HER2, Akt, P-Erk1/2 and survivin protein levels in SKBR-3 cells a short time after its application. In this regard, 17-DMAG protected also SKBR-3 cells against both P-Erk1/2 as well as survivin upregulations induced by photodynamic therapy with hypericin. Interestingly, IC10 concentration of 17-DMAG led to total depletion of Akt, P-Erk1/2 proteins and to decrease of survivin level at 48 h. On the other hand, 17-DMAG did not change HER2 relative expression in SKBR-3 cells, but caused a significant decrease of HER2 mRNA in MCF-7 cells characterized by low HER2 expression. These results show that targeting HSP90 client proteins increases the efficiency of antineoplastic effect of photodynamic therapy in vitro. PMID:27721334

Comparing the efficacy of photodynamic and sonodynamic therapy in non-melanoma and melanoma skin cancer.

PubMed

McEwan, Conor; Nesbitt, Heather; Nicholas, Dean; Kavanagh, Oisin N; McKenna, Kevin; Loan, Philip; Jack, Iain G; McHale, Anthony P; Callan, John F

2016-07-01

Sonodynamic therapy (SDT) involves the activation of a non-toxic sensitiser drug using low-intensity ultrasound to produce cytotoxic reactive oxygen species (ROS). Given the low tissue attenuation of ultrasound, SDT provides a significant benefit over the more established photodynamic therapy (PDT) as it enables activation of sensitisers at a greater depth within human tissue. In this manuscript, we compare the efficacy of aminolevulinic acid (ALA) mediated PDT and SDT in a squamous cell carcinoma (A431) cell line as well as the ability of these treatments to reduce the size of A431 ectopic tumours in mice. Similarly, the relative cytotoxic ability of Rose Bengal mediated PDT and SDT was investigated in a B16-melanoma cell line and also in a B16 ectopic tumour model. The results reveal no statistically significant difference in efficacy between ALA mediated PDT or SDT in the non-melanoma model while Rose Bengal mediated SDT was significantly more efficacious than PDT in the melanoma model. This difference in efficacy was, at least in part, attributed to the dark pigmentation of the melanoma cells that effectively filtered the excitation light preventing it from activating the sensitiser while the use of ultrasound circumvented this problem. These results suggest SDT may provide a better outcome than PDT when treating highly pigmented cancerous skin lesions. Copyright © 2016. Published by Elsevier Ltd.

A Review of Progress in Clinical Photodynamic Therapy

PubMed Central

Huang, Zheng

2005-01-01

Photodynamic therapy (PDT) has received increased attention since the regulatory approvals have been granted to several photosensitizing drugs and light applicators world-wide. Much progress has been seen in basic sciences and clinical photodynamics in recent years. This review will focus on new developments of clinical investigation and discuss the usefulness of various forms of PDT techniques for curative or palliative treatment of malignant and non-malignant diseases. PMID:15896084

Effectiveness of Photodynamic Therapy in Elimination of HPV-16 and HPV-18 Associated with CIN I in Mexican Women.

PubMed

Maldonado Alvarado, Elizabeth; Osorio Peralta, Martha Olivia; Moreno Vázquez, Alejandra; Martínez Guzmán, Lydia Alejandra; Melo Petrone, Maria Eugenia; Enriquez Mar, Zulma Iveth; Jovel Galdamez, Dora Estela; Carrión Solana, Bárbara; Balderas Martínez, Guadalupe; Parra, Eduarda; Castellanos Oliveros, Rossana Inés; Bello Leiva, Rosa Linda; Espinosa Montesinos, Araceli; Barrera Mendoza, Citlalli; Medina García, Selma Eugenia; Ramón Gallegos, Eva

2017-10-01

This study aimed to determine the effectiveness of photodynamic therapy (PDT), using δ-aminolevulinic acid (5-ALA), in the elimination of premalignant cervical lesions in Mexican patients with human papillomavirus (HPV) infection and/or cervical intraepithelial neoplasia (CIN). Thirty women diagnosed with CIN I and/or positive for HPV participated in the study. Topical 6% 5-ALA in gel form was applied to the uterine cervix; after 4 h, the lesion area was irradiated with a light dose of 200 J cm -2 at 635 nm. This procedure was performed three times at 48-h intervals. Clinical follow-up was performed at 3, 6, and 12 months after the initial PDT administration, by colposcopy, cervical cytology, histopathological analysis, polymerase chain reaction, and hybrid capture. Of HPV-infected patients without evidence of CIN I, 80% cleared the infection, while HPV associated with CIN I was eliminated in 83% of patients (P < 0.05). At 12 months, CIN I had regressed in 57% of patients, although this response was not statistically significant. PDT using 6% 5-ALA is concluded to be effective in eliminating HPV infection associated or not with CIN I. © 2017 The American Society of Photobiology.

Upconversion Nanoparticles for Photodynamic Therapy and Other Cancer Therapeutics

PubMed Central

Wang, Chao; Cheng, Liang; Liu, Zhuang

2013-01-01

Photodynamic therapy (PDT) is a non-invasive treatment modality for a variety of diseases including cancer. PDT based on upconversion nanoparticles (UCNPs) has received much attention in recent years. Under near-infrared (NIR) light excitation, UCNPs are able to emit high-energy visible light, which can activate surrounding photosensitizer (PS) molecules to produce singlet oxygen and kill cancer cells. Owing to the high tissue penetration ability of NIR light, NIR-excited UCNPs can be used to activate PS molecules in much deeper tissues compared to traditional PDT induced by visible or ultraviolet (UV) light. In addition to the application of UCNPs as an energy donor in PDT, via similar mechanisms, they could also be used for the NIR light-triggered drug release or activation of 'caged' imaging or therapeutic molecules. In this review, we will summarize the latest progresses regarding the applications of UCNPs for photodynamic therapy, NIR triggered drug and gene delivery, as well as several other UCNP-based cancer therapeutic approaches. The future prospects and challenges in this emerging field will be also discussed. PMID:23650479

Mechanism of enhanced responses after combination photodynamic therapy (cPDT) in carcinoma cells involves C/EBP-mediated transcriptional upregulation of the coproporphyrinogen oxidase (CPO) gene

NASA Astrophysics Data System (ADS)

Anand, Sanjay; Hasan, Tayyaba; Maytin, Edward V.

2013-03-01

Photodynamic therapy (PDT) with aminolevulinate (ALA) is widely accepted as an effective treatment for superficial carcinomas and pre-cancers. However, PDT is still suboptimal for deeper tumors, mainly due to inadequate ALA penetration and subsequent conversion to PpIX. We are interested in improving the effectiveness of photodynamic therapy (PDT) for deep tumors, using a combination approach (cPDT) in which target protoporphyrin (PpIX) levels are significantly enhanced by differentiation caused by giving Vitamin D or methotrexate (MTX) for 3 days prior to ALAPDT. In LNCaP and MEL cells, a strong correlation between inducible differentiation and expression of C/EBP transcription factors, as well as between differentiation and mRNA levels of CPO (a key heme-synthetic enzyme), indicates the possibility of CPO transcriptional regulation by the C/EBPs. Sequence analysis of the first 1300 base pairs of the murine CPO upstream region revealed 15 consensus C/EBP binding sites. Electrophoretic Mobility Shift Assays (EMSA) proved that these sites form specific complexes that have strong, moderate or weak affinities for C/EBPs. However, in the context of the full-length CPO promoter, inactivation of any type of site (strong or weak) reduced CPO promoter activity (luciferase assay) to nearly the same extent, suggesting cooperative interactions. A comparative analysis of murine and human CPO promoters revealed possible protein-protein interactions between C/EBPs and several neighboring transcription factors such as NFkB, Sp1, AP-1, CBP/p300 and CREB (an enhanceosome complex). Overall, these results confirm that C/EBP's are important for CPO expression via complex mechanisms which upregulate PpIX and enhance the outcome of cPDT.

Photodynamic therapy platform for glioblastoma and intrabronchial tumors

NASA Astrophysics Data System (ADS)

Orsila, Lasse; Alanko, Jukka-Pekka; Kaivosoja, Visa; Uibu, Toomas

2018-02-01

Photodynamic therapy (PDT) is bringing new, effective, and less invasive, possibilities for cancer treatment. ML7710 (Modulight Inc.) medical laser system offers a platform for performing PDT for multiple indications and drugs. Latest avenue is glioblastoma treatment with 5-Aminolevulinic acid (ALA-5) and 635-nm light, where clinical trials are about to begin. Preliminary work suggests major advantages in treatment control, including active in-situ feedback. ML7710 platform has already proven itself for clinical work with intrabronchial obstructive tumors. Preliminary result with 10 patients show that intrabronchial tumors, that strongly affect both the survival and the performance of the patient, can be significantly reduced with ML7710 operated at 665 nm and sodium chlorine E6 photosensitizer. The aim in most of the patients has been a palliative recanalization of the bronchial lumen in order to alleviate the symptoms such as breathlessness and hemoptysis. The illumination dose for the target area was 50-75 J/cm2. All the patients have received multimodality cancer treatment using other intrabronchial interventions, radiotherapy and chemotherapy as needed. In most of the patients, satisfactory treatment results were achieved and it was possible to restart chemotherapy in several patients. In one patient with local cancer a complete remission was established. PDT has also the advantage that it is possible to give PDT after a maximum dose of radiation therapy has already been used and fewer side effects if used in locally advanced intraluminar lung cancer.

Physiological oxygen concentration alters glioma cell malignancy and responsiveness to photodynamic therapy in vitro.

PubMed

Albert, Ina; Hefti, Martin; Luginbuehl, Vera

2014-11-01

The partial pressure of oxygen (pO2) in brain tumors ranges from 5 to 15%. Nevertheless, the majority of in vitro experiments with glioblastoma multiforme (GBM) cell lines are carried out under an atmospheric pO2 of 19 to 21%. Recently, 5-aminolevulinic acid (5-ALA), a precursor of protoporphyrin IX (PpIX), has been introduced to neurosurgery to allow for photodynamic diagnosis and photodynamic therapy (PDT) in high-grade gliomas. Here, we investigate whether low pO2 affects GBM cell physiology, PpIX accumulation, or PDT efficacy. GBM cell lines (U-87 MG and U-251 MG) were cultured under atmospheric (pO2  =  19%) and physiological (pO2  =  9%) oxygen concentrations. PpIX accumulation and localization were investigated, and cell survival and cell death were observed following in vitro PDT. A physiological pO2 of 9% stimulated GBM cell migration, increased hypoxia-inducible factor (HIF)-1 alpha levels, and elevated resistance to camptothecin in U-87 MG cells compared to cultivation at a pO2 of 19%. This oxygen reduction did not alter 5-ALA-induced intracellular PpIX accumulation. However, physiological pO2 changed the responsiveness of U-87 MG but not of U-251 MG cells to in vitro PDT. Around 20% more irradiation light was required to kill U-87 MG cells at physiological pO2, resulting in reduced lactate dehydrogenase (LDH) release (one- to two-fold) and inhibition of caspase 3 activation. Reduction of oxygen concentration from atmospheric to a more physiological level can influence the malignant behavior and survival of GBM cell lines after in vitro PDT. Therefore, precise oxygen concentration control should be considered when designing and performing experiments with GBM cells.

"Smart" nickel oxide based core-shell nanoparticles for combined chemo and photodynamic cancer therapy.

PubMed

Bano, Shazia; Nazir, Samina; Munir, Saeeda; AlAjmi, Mohamed Fahad; Afzal, Muhammad; Mazhar, Kehkashan

2016-01-01

We report "smart" nickel oxide nanoparticles (NOPs) as multimodal cancer therapy agent. Water-dispersible and light-sensitive NiO core was synthesized with folic acid (FA) connected bovine serum albumin (BSA) shell on entrapped doxorubicin (DOX). The entrapped drug from NOP-DOX@BSA-FA was released in a sustained way (64 hours, pH=5.5, dark conditions) while a robust release was found under red light exposure (in 1/2 hour under λmax=655 nm, 50 mW/cm(2), at pH=5.5). The cell viability, thiobarbituric acid reactive substances and diphenylisobenzofuran assays conducted under light and dark conditions revealed a high photodynamic therapy potential of our construct. Furthermore, we found that the combined effect of DOX and NOPs from NOP-DOX@BSA-FA resulted in cell death approximately eightfold high compared to free DOX. We propose that NOP-DOX@BSA-FA is a potential photodynamic therapy agent and a collective drug delivery system for the systemic administration of cancer chemotherapeutics resulting in combination therapy.

Evaluation of Silicon Phthalocyanine 4 Photodynamic Therapy Against Human Cervical Cancer Cells In Vitro and in Mice

PubMed Central

Gadzinski, Jill A.; Guo, Jianxia; Philips, Brian J.; Basse, Per; Craig, Ethan K.; Bailey, Lisa; Comerci, John T.; Eiseman, Julie L.

2017-01-01

Background Cervical cancer is the second most common cancer in women worldwide [1]. Photodynamic therapy has been used for cervical intraepithelial neoplasia with good responses, but few studies have used newer phototherapeutics. We evaluated the effectiveness of photodynamic therapy using Pc 4 in vitro and in vivo against human cervical cancer cells. Methods CaSki and ME-180 cancer cells were grown as monolayers and spheroids. Cell growth and cytotoxicity were measured using a methylthiazol tetrazolium assay. Pc 4 cellular uptake and intracellular distrubtion were determined. For in vitro Pc 4 photodynamic therapy cells were irradiated at 667nm at a fluence of 2.5 J/cm2 at 48 h. SCID mice were implanted with CaSki and ME-180 cells both subcutaneously and intracervically. Forty-eight h after Pc 4 photodynamic therapy was administered at 75 and 150 J/cm2. Results The IC50s for Pc 4 and Pc 4 photodynamic therapy for CaSki and ME-180 cells as monolayers were, 7.6μM and 0.016μM and >10μM and 0.026μM; as spheroids, IC50s of Pc 4 photodynamic therapy were, 0.26μM and 0.01μM. Pc 4 was taken up within cells and widely distributed in tumors and tissues. Intracervical photodynamic therapy resulted in tumor death, however mice died due to gastrointestinal toxicity. Photodynamic therapy resulted in subcutaneous tumor death and growth delay. Conclusions Pc 4 photodynamic therapy caused death within cervical cancer cells and xenografts, supporting development of Pc 4 photodynamic therapy for treatment of cervical cancer. Support: P30-CA47904, CTSI BaCCoR Pilot Program. PMID:28890844

The Role of Photodynamic Therapy in the Treatment of Vulvar Intraepithelial Neoplasia

PubMed Central

Tosti, Giulio; Iacobone, Anna Daniela; Preti, Eleonora Petra; Vaccari, Sabina; Barisani, Alessia; Pennacchioli, Elisabetta

2018-01-01

Background: vulvar intraepithelial neoplasia is a non-invasive precursor lesion found in 50–70% of patients affected by vulvar squamous cell carcinoma. In the past, radical surgery was the standard treatment for vulvar intraepithelial neoplasia, however, considering the psychological and physical morbidities related to extensive surgery, several less aggressive treatment modalities have been proposed since the late 1970s. Photodynamic therapy is an effective and safe treatment for cutaneous non-melanoma skin cancer, with favorable cosmetic outcomes. Methods: in the present paper, the results of selected studies on photodynamic therapy in the treatment of vulvar intraepithelial neoplasia are reported and discussed. Results: Overall, complete histological response rates ranged between 20% and 67% and symptom response rates ranged between 52% and 89% according to different studies and case series. Conclusions: the real benefit of photodynamic therapy in the setting of vulvar intraepithelial neoplasia lies in its ability to treat multi-focal disease with minimal tissue destruction, preservation of vulvar anatomy and excellent cosmetic outcomes. These properties explain why photodynamic therapy is an attractive option for vulvar intraepithelial neoplasia treatment. PMID:29393881

A new LED device used for photodynamic therapy in treatment of moderate to severe acne vulgaris.

PubMed

Dong, Yiyun; Zhou, Guoyu; Chen, Jinan; Shen, Lingyue; Jianxin, Zhao; Xu, Qing; Zhu, Yulan

2016-03-01

This study investigated the efficacy and safety of a newly designed LED device used in photodiagnosis and photodynamic therapy of moderate to severe acne vulgaris in Chinese patients. Forty-six patients with moderate to severe facial acne showing high degrees of fluorescence by ultraviolet light examination were illuminated during ALA-PDT with two wavelengths of light (543-548 nm, and 630±6 nm, respectively) after 2 h of incubation with ALA. Each patient received treatment once every 30 days for two or three sessions. Two independent investigators assigned an acne severity score at baseline, one week after each treatment, as well as 4, 8, and 12 weeks after the completion of treatment. Adverse effects were recorded during and after each treatment. All patients rated their satisfaction with the results of treatment at a 12-week follow up visit. The ALA-PDL treatment regimen showed an overall effectiveness rate of 89.13% (41/46 patients). Some degree of clinical efficacy was seen in 71.42%, 86.67%, and 95.83% of patients with grades IV, V, and VI acne, respectively, and the rate of clinical effectiveness increased with increasing acne severity. When compared with baseline scores, significant reductions in acne scores were obtained at 8, and 12 weeks after completion of treatment. Maximum efficacy was shown at the 12 week follow up. No severe adverse events were observed. ALA-PDT administered with the newly designed LED device was an effective treatment for moderate to severe acne vulgaris, and side effects were mild and reversible. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparsion of light dose on topical ALA-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premalignant lesions

NASA Astrophysics Data System (ADS)

Yang, Deng-Fu; Tseng, Meng-Ke; Liu, Chung-Ji; Hsu, Yih-Chih

2012-03-01

Oral cancer has becomes the most prominent male cancer disease due to the local betel nut chewing habit combing with smoking and alcohol-drinking lifestyle. In order to minimize the systemic phototoxic effect of 5-aminolevulinic acid (ALA), this study was designed to use a topical ALA-mediated PDT for treatment of DMBA-induced hamster buccal pouch cancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 8 to 10 weeks. Precancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical ALA -mediated PDT. We found that ALA reached its peak level in cancerous lesions about 2.5 hrs after topical application of ALA gel. The precancerous lesions in hamsters were then treated with topical ALA -mediated PDT with light exposure dose of 75 and 100 J/cm2 using LED 635 nm Wonderlight device. It is suggesting that optimization of the given light dose is critical to the success of PDT results.

The role of DAMPS in ALA-PDT for skin squamous cell carcinoma (Conference Presentation)

NASA Astrophysics Data System (ADS)

Wang, Xiuli; Wang, Xiaojie; Ji, Jie; Zhang, Haiyan; Shi, Lei

2016-03-01

5-Aminolevulinic acid mediated photodynamic therapy (ALA-PDT) is an established local approach for skin squamous cell carcinoma. It is believed that dangerous signals damage-associated molecular patterns (DAMPs) play an important role in ALA-PDT. In this study, we evaluated in vitro and in vivo expressions of major DAMPs, calreticulin (CRT), heat shock proteins 70 (HSP70), and high mobility group box 1 (HMGB1), induced by ALA-PDT using immunohistochemistry, western blot, and ELISA in a squamous cell carcinoma (SCC) mouse model. The role of DAMPs in the maturation of DCs potentiated by ALA-PDT-treated tumor cells was detected by FACS and ELISA. Our results showed that ALA-PDT enhanced the expression of CRT, HSP70, and HMGB1. These induced DAMPs played an important role in activating DCs by PDT-treated tumor cells, including phenotypic maturation (upregulation of surface expression of MHC-II, CD80, and CD86) and functional maturation (enhanced capability to secrete IFN-γ and IL-12). Furthermore, injecting ALA-PDT-treated tumor cells into naïve mice resulted in complete protection against cancer cells of the same origin. Our findings indicate that ALA-PDT can upregulate DAMPs and enhance tumor immunogenicity, providing a promising strategy for inducing a systemic anticancer immune response.

Recent patents on light based therapies: photodynamic therapy, photothermal therapy and photoimmunotherapy.

PubMed

Sanchez-Barcelo, Emilio J; Mediavilla, Maria D

2014-01-01

This article reviews the more recent patents in three kinds of therapeutic strategies using the application of visible light to irradiate photosensible substances (PSs) of different natures. The light-activation of these PSs is directly responsible for the desired therapeutic effects. This group of light therapies includes photodynamic therapy (PDT), photothermal therapy (PTT) and photoimmunotherapy (PIT). Therapeutic mechanisms triggered by the activation of the PSs depend basically (though not exclusively) on the release of reactive oxygen species (ROS) and the activation of immune responses (PDT and PIT) or the local generation of heat (PTT). The main difference between PIT and PDT is that in PIT, monoclonal antibodies (MABs) are associated to PSs to improve the selective binding of the PSs to the target tissues. All these therapeutic strategies offer the possibility of destroying tumor tissue without damaging the surrounding healthy tissue, which is not achievable with chemotherapy or radiotherapy. PDT is also used as an alternative or adjuvant antimicrobial therapy together with the traditional antibiotic therapy since these organisms are unlikely to develop resistance to the ROS induced by PDT. Furthermore, PDT also induces an immune response against bacterial pathogens. The current challenge in PDT, PIT and PTT is to obtain the highest level of selectivity to act on targeted sick tissues with the minimum effects on the surrounding healthy tissue. The development of new PSs with high affinity for specific tissues, new PSs- MABs conjugates to bind to specific kinds of tumors, and new light-sensible nanoparticles with low toxicity, will increase the clinical utility of these therapies.

Photodynamic therapy (PDT) utilizing PhotofrinR for treatment of early esophageal cancer

NASA Astrophysics Data System (ADS)

Overholt, Bergein F.; Panjehpour, Masoud; Teffeteller, Elmeria; Rose, S. Mark

1993-06-01

Four lesions of early carcinoma of the esophagus found during endoscopic biopsies in three patients were treated with photodynamic therapy. Follow-up biopsies over 9 - 24 months remain negative for carcinoma. Endoscopic ultrasonography is essential for proper staging and treatment planning for these patients. Photodynamic therapy may provide an alternative to surgical resection for early esophageal carcinoma or severe dysplasia in Barrett's esophagus.

Combined photothermal and photodynamic therapy delivered by PEGylated MoS2 nanosheets

NASA Astrophysics Data System (ADS)

Liu, Teng; Wang, Chao; Cui, Wei; Gong, Hua; Liang, Chao; Shi, Xiaoze; Li, Zhiwei; Sun, Baoquan; Liu, Zhuang

2014-09-01

Single- or few-layered transitional metal dichalcogenides, as a new genus of two-dimensional nanomaterials, have attracted tremendous attention in recent years, owing to their various intriguing properties. In this study, chemically exfoliated MoS2 nanosheets are modified with lipoic acid-terminated polyethylene glycol (LA-PEG), obtaining PEGylated MoS2 (MoS2-PEG) with high stability in physiological solutions and no obvious toxicity. Taking advantage of its ultra-high surface area, the obtained MoS2-PEG is able to load a photodynamic agent, chlorin e6 (Ce6), by physical adsorption. In vitro experiments reveal that Ce6 after being loaded on MoS2-PEG shows remarkably increased cellular uptake and thus significantly enhanced photodynamic therapeutic efficiency. Utilizing the strong, near-infrared (NIR) absorbance of the MoS2 nanosheets, we further demonstrate photothermally enhanced photodynamic therapy using Ce6-loaded MoS2-PEG for synergistic cancer killing, in both in vitro cellular and in vivo animal experiments. Our study presents a new type of multifunctional nanocarrier for the delivery of photodynamic therapy, which, if combined with photothermal therapy, appears to be an effective therapeutic approach for cancer treatment.Single- or few-layered transitional metal dichalcogenides, as a new genus of two-dimensional nanomaterials, have attracted tremendous attention in recent years, owing to their various intriguing properties. In this study, chemically exfoliated MoS2 nanosheets are modified with lipoic acid-terminated polyethylene glycol (LA-PEG), obtaining PEGylated MoS2 (MoS2-PEG) with high stability in physiological solutions and no obvious toxicity. Taking advantage of its ultra-high surface area, the obtained MoS2-PEG is able to load a photodynamic agent, chlorin e6 (Ce6), by physical adsorption. In vitro experiments reveal that Ce6 after being loaded on MoS2-PEG shows remarkably increased cellular uptake and thus significantly enhanced photodynamic

A laser-spectroscopy complex for fluorescent diagnostics and photodynamic therapy of age-related macula degeneration

NASA Astrophysics Data System (ADS)

Shevchik, S. A.; Meerovich, Gennadii A.; Budzinskaya, M. V.; Ermakova, N. A.; Kharnas, Sergey S.; Loschenov, Victor B.

2004-06-01

A laser-spectroscopy complex was developed for fluorescent diagnostics and photodynamic therapy of age related macula degeneration using the Russian photosensitizer Photosense. The complex is based on slit lamp which was additionally equipped with an optical adapter, and the video adapter allows to combine the procedure of photodynamic therapy and the control of its carrying in the frame work of one procedure. The sensitivity and spatial resolution of the complex were investigated using a special test object. The availability of the developed complex and Photosense itself was examined on experimental animals.

Utilization of 5-aminolevulinic acid in the photodynamic therapy of tumors: biochemical and photobiological aspects

NASA Astrophysics Data System (ADS)

Pottier, Roy H.; Kennedy, James C.

1994-03-01

Inherent in both plants and animals is the natural porphyrin, Protoporphyrin IX (Pp). Although Pp does not appear to have any intrinsic biological activity, it is a potent natural photosensitizer. When activated with ultraviolet or visible light, this photosensitizer can induce significant photodynamic effects on tissues, cells, subcellular elements, and macromolecules via the production of singlet oxygen. The biosynthesis of endogenous Pp is under strict enzymatic control. It is possible to bypass a rate controlling step and induce large, transient concentrations of Pp by the addition of exogenous 5-aminolevulinic acid (ALA). ALA may be administered systemically or topically. Much larger amounts of Pp are produced in certain types of tumor tissue than in adjacent normal tissue. Topically applied ALA can be used to treat a variety of skin lesions, including actinic keratosis, basal cell carcinomas and psoriasis.

Drug Carrier for Photodynamic Cancer Therapy

PubMed Central

Debele, Tilahun Ayane; Peng, Sydney; Tsai, Hsieh-Chih

2015-01-01

Photodynamic therapy (PDT) is a non-invasive combinatorial therapeutic modality using light, photosensitizer (PS), and oxygen used for the treatment of cancer and other diseases. When PSs in cells are exposed to specific wavelengths of light, they are transformed from the singlet ground state (S0) to an excited singlet state (S1–Sn), followed by intersystem crossing to an excited triplet state (T1). The energy transferred from T1 to biological substrates and molecular oxygen, via type I and II reactions, generates reactive oxygen species, (1O2, H2O2, O2*, HO*), which causes cellular damage that leads to tumor cell death through necrosis or apoptosis. The solubility, selectivity, and targeting of photosensitizers are important factors that must be considered in PDT. Nano-formulating PSs with organic and inorganic nanoparticles poses as potential strategy to satisfy the requirements of an ideal PDT system. In this review, we summarize several organic and inorganic PS carriers that have been studied to enhance the efficacy of photodynamic therapy against cancer. PMID:26389879

Development of Smart Phthalocyanine-based Photosensitizers for Photodynamic Therapy

NASA Astrophysics Data System (ADS)

Chow, Yun Sang

Phthalocyanines are versatile functional dyes that have shown great potential in cancer theranostics, especially in photodynamic therapy (PDT). This research work aims to develop "smart" phthalocyanine-based photosensitizers for targeted PDT. This thesis describes the synthesis, spectroscopic characterization, photophysical properties, and in vitro photodynamic activities of several series of carefully designed phthalocyanine-based photosensitizers. Chapter 1 presents an overview of PDT, including its historical development, photophysical mechanisms, and biological mechanisms. Various classes of photosensitizers are introduced with emphasis putting on phthalocyanines, which exhibit ideal characteristics of photosensitizers for PDT. In recent years, several approaches have been used to develop photosensitizers with higher tumor selectivity and minimal skin photosensitivity after PDT. Activatable photosensitizers can provide a "turn on" mechanism to offer an additional control of the specificity of treatment. Photosensitizers can also work cooperatively with the tumor-targeting groups or anticancer drugs so as to achieve targeted or dual therapy, which can enhance the efficacy of PDT. The novel approaches mentioned above have been widely used and combined to form multi-functional photosensitizing agents. These novel concepts and development of PDT are discussed and illustrated with relevant examples at the end of this chapter. To minimize the prolonged skin photosensitivity, photosensitizers that can only be activated by tumor-associated stimuli have been developed. Due to the abnormal metabolism in tumor tissues, their surface usually exhibits a lower pH compared to that of the normal tissues. Also, the pH difference between the intracellular and the physiological environment provides a pH-activation mechanism. Chapter 2 presents the synthesis and spectroscopic characterization of a pH-responsive zinc(II) phthalocyanine tetramer, in which the phthalocyanine units

A Nanosystem Capable of Releasing a Photosensitizer Bioprecursor under Two‐Photon Irradiation for Photodynamic Therapy

PubMed Central

Wu, Hao; Zeng, Fang; Zhang, Hang; Xu, Jiangsheng

2015-01-01

The applications of photodynamic therapy (PDT) are usually limited by photosensitizers' side effects and singlet oxygen's short half‐life. Herein, a mitochondria‐targeted nanosystem is demonstrated to enhance the PDT efficacy by releasing a bio‐precursor of photosensitizer under two‐photon irradiation. A phototriggerable coumarin derivative is first synthesized by linking 5‐aminolevulinic acid (5‐ALA, the bio‐precursor) to coumarin; and the nanosystem (CD‐ALA‐TPP) is then fabricated by covalently incorporating this coumarin derivative and a mitochondria‐targeting compound triphenylphosphonium (TPP) onto carbon dots (CDs). Upon cellular internalization, the nanosystem preferentially accumulates in mitochondria; and under one‐ or two‐photon irradiation, it releases 5‐ALA molecules that are then metabolized into protoporphyrin IX in mitochondria through a series of biosynthesis processes. The subsequent red light irradiation induces this endogenously synthesized photosensitizer to generate singlet oxygen, thereby causing oxidant damage to mitochondria and then the apoptosis of the cells. Analysis via 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyltetrazolium bromide (MTT) assays indicate that the novel PDT system exhibits enhanced cytotoxicity toward cancer cells. This study may offer a new strategy for designing PDT systems with high efficacy and low side effects. PMID:27774388

Photodynamic therapy in combination with CO2 laser for the treatment of Bowen's disease.

PubMed

Cai, Hong; Wang, Yi-xia; Zheng, Ji-Chun; Sun, Ping; Yang, Zhi-yong; Li, Yuan-li; Liu, Xiao-yong; Li, Qiang; Liu, Wei

2015-07-01

Photodynamic therapy (PDT) involves the activation of a previously administered photosensitizing agent by visible light to induce tumor necrosis. Photosensitizers are topically applied in the treatment of skin tumors to avoid systemic side effects. In this study, we evaluated the feasibility and efficacy of aminolevulinic acid (ALA) as a photosensitizer (ALA-PDT) in combination with CO2 laser in the treatment of Bowen's disease (BD; intraepithelial squamous cell carcinoma). Twenty-two lesions from 18 patients were randomized into two groups: 11 lesions were treated with topical ALA-PDT (180 J/cm(2) at 100 mW/cm(2)) + CO2 laser for one to three sessions. The remaining 11 lesions were treated with CO2 laser alone, serving as control group. All patients were reviewed at ≤1-week intervals. Biopsies were taken from BD lesions prior to treatment. The initial evaluation was undertaken 1 month after treatment, and biopsies were harvested for histological evaluation. Patients who did not respond to the three sessions of treatment were referred to surgical treatment. In the ALA-PDT + CO2 laser group, 72.73 % (8/11) of BD lesions showed complete remission, with an overall clearance of 90.91 %, and only one recurred (9 %) during follow-up. Local side effects included mild erythema, edema, erosion, and burning and/or stinging sensation. No systemic side effects were observed. In the control group, 63.63 % (7/11) of lesions had complete remission and the overall clearance was 54.55 %. However, five lesions (45.45 %) had recurrence. Local side effects included mild to moderate edema, erosion, ulceration, delayed healing, prolonged pain, and scarring. There existed a significant difference in recurrence rate between the two groups (P < 0.05). Moreover, after ALA-PDT plus CO2 laser treatment, complete necrosis was observed in responsive lesions, and 3 months later, the atypical BD cells were replaced by normal keratinocytes. Topical ALA-PDT in combination

Immune Response Following Photodynamic Therapy For Bladder Cancer

NASA Astrophysics Data System (ADS)

Raymond K.

1989-06-01

This study was undertaken to determine if photodynamic therapy (PDT) produces an immunologic response in patients treated for bladder cancer. Gamma interferon, interleukin 1-beta, interleukin 2 and tumor necrosis factor-alpha were assayed in the urine of four patients treated with photodynamic therapy for bladder cancer, in seven patients undergoing transurethral procedures, and in five healthy control subjects. Quantifiable concentrations of all cytokines, except gamma interferon, were measured in urine samples from the PDT patients treated with the highest light energies, while no urinary cytokines were found in the PDT patient who received the lowest light energy or in the control subjects. These findings suggest that a local immunologic response may occur following PDT for bladder cancer. Such an immunologic response activated by PDT may be an additional mechanism involved in bladder tumor destruction.

Topical application of ALA PDT for the treatment of moderate to severe acne vulgaris

NASA Astrophysics Data System (ADS)

Wang, Xiu-Li; Wang, Hong-Wei; Zhang, Ling-Lin; Su, Lina; Guo, Ming-Xia; Huang, Zheng

2009-06-01

Objectives: To evaluate the effectiveness of topical 5-aminolevulinic acid (ALA)- medicated photodynamic therapy (ALA PDT) for the treatment of moderate to severe acne vulgaris. Methods: Sixteen Chinese patients with moderate to severe facial acne were treated with 1-3 courses of ALA PDT. ALA cream (3%) was freshly prepared and applied to acne lesions for 3-4 h. The lesions were irradiated by a 635 nm diode laser at dose levels of 60 - 80 J/cm2 at 100 mW/cm2. Clinical assessments were conducted before and after treatment up to 3 months. Results: All patents showed response to ALA PDT. Complete clearance was seen in 10 patients (62.5%) and partial clearance in 6 patients (37.5%). One case showed recurrence after complete clearance at 2 months and another two showed recurrence after complete clearance at 3 months. However, the number of new lesions were significantly reduced. Adverse effects were minimal. Conclusions: The results of this preliminary clinical study is encouraging. ALA PDT is a simple, safe and useful therapeutic option for the treatment of moderate to severe acne. Further studies to evaluate the treatment with a larger number of patients and for a longer period of follow-up are needed.

Photodynamic therapy and the treatment of neoplastic diseases of the larynx

NASA Astrophysics Data System (ADS)

Biel, Merrill A.

1995-05-01

Photodynamic therapy (PDT) is an innovative treatment involving the use of light-sensitive drugs to selectively identify and destroy diseased cells. Therefore, photodynamic therapy has the potential to treat and cure precancerous and early cancerous lesions (carcinoma in situ (CIS), T1 and T2) of the larynx while preserving normal tissue. Twenty-four patients with recurrent leukoplakia and carcinomas of the larynx were treated with PDT with follow-up to 60 months. Fourteen patients with T1 squamous cell carcinomas of the vocal cord, 2 patients with a T2 squamous cell carcinoma of the vocal cord failing radiotherapy, and 6 patients with CIS and sever atypia were treated with PDT and obtained a complete response and are disease free. One patient with a T3 carcinoma of the larynx was treated with PDT but died 5 weeks post-treatment of unrelated causes and could not be assessed. Photodynamic therapy is a promising therapy for treatment of precancerous and cancerous lesions of the larynx. This therapy may be particularly beneficial for the treatment of recurrent carcinomas of the larynx that have failed conventional radiotherapy, thereby preserving voice and eliminating the need for destructive laryngeal surgery.

Antimicrobial Photodynamic Inactivation and Antitumor Photodynamic Therapy with Fullerenes

NASA Astrophysics Data System (ADS)

de Freitas, Lucas F.

2016-04-01

This book provides detailed and current information on using fullerenes (bucky-balls) in photodynamic therapy (PDT), one of the most actively studied applications of photonic science in healthcare. This will serve as a useful source for researchers working in photomedicine and nanomedicine, especially those who are investigating PDT for cancer treatment and infectious disease treatment. The book runs the gamut from an introduction to the history and chemistry of fullerenes and some basic photochemistry, to the application of fullerenes as photosensitizers for cancer and antimicrobial inactivation.

Effectiveness of repeated photodynamic therapy in the elimination of intracanal Enterococcus faecalis biofilm: an in vitro study.

PubMed

Prażmo, Ewa Joanna; Godlewska, Renata Alicja; Mielczarek, Agnieszka Beata

2017-04-01

The study aimed to investigate the effectiveness of photodynamic therapy in the elimination of intracanal Enterococcus faecalis biofilm and to analyse how a repeated light irradiation, replenishment of oxygen and photosensitiser affect the results of the photodynamic disinfecting protocol. After chemomechanical preparation, 46 single-rooted human teeth were infected with a clinical strain of E. faecalis and incubated for a week in microaerobic conditions. The experimental procedures included groups of single application of photodynamic therapy, two cycles of PDT, irrigation with 5.25% NaOCl solution and negative and positive control. The number of residing bacterial colonies in the root canals was determined based on the CFU/ml method. In the group of preparations irrigated with NaOCl, bacterial colonies were not observed. A single PDT eliminated 45% of the initial CFU/ml. Repeated PDT eradicated 95% of the intracanal bacterial biofilm. Photodynamic therapy has a high potential for the elimination of E. faecalis biofilm. There is a safe therapeutic window where photoinduced disinfection can be used as an adjuvant to conventional endodontic treatment, which remains the most effective.

Photodynamic therapy for polypoidal choroidal vasculopathy secondary to choroidal nevus.

PubMed

Wong, James G; Lai, Xin Jie; Sarafian, Richard Y; Wong, Hon Seng; Smith, Jeremy B

2017-01-01

We report a case of a Caucasian female who developed active polypoidal choroidal vasculopathy (PCV) at the edge of a stable choroidal nevus and was successfully treated with verteporfin photodynamic therapy. No active polyp was detectable on indocyanine green angiography 2 years after treatment, and good vision was maintained. Indocyanine green angiography is a useful investigation to diagnose PCV and may be underutilized. Unlike treatment of choroidal neovascularization secondary to choroidal nevus, management of PCV secondary to nevus may not require intravitreal anti-vascular endothelial growth factor therapy. Photodynamic monotherapy may be an effective treatment of secondary PCV.

Combination of active targeting, enzyme-triggered release and fluorescent dye into gold nanoclusters for endomicroscopy-guided photothermal/photodynamic therapy to pancreatic ductal adenocarcinoma.

PubMed

Li, Hui; Wang, Ping; Deng, Yunxiang; Zeng, Meiying; Tang, Yan; Zhu, Wei-Hong; Cheng, Yingsheng

2017-09-01

Pancreatic ductal adenocarcinoma (PDAC) is one of the most devastating malignancies in patients, and there is an urgent need for an effective treatment method. Herein, we report a novel gold nanocluster-based platform for confocal laser endomicroscopy-guided photothermal therapy (PTT)/photodynamic therapy (PDT) for PDAC, which consists of four components: the PTT-carrier gold nanocluster, an active targeting ligand U11 peptide, a Cathepsin E (CTSE)-sensitive PDT therapy prodrug, and a CTSE-sensitive imaging agent (cyanine dye Cy5.5). Due to the strong coupling among cross-linked gold nanoparticles (AuNPs), the surface plasmon resonance peak of nanoclusters shifts to the near-infrared (NIR) region, thus making the nanoclusters useful in the effective PTT therapy. In the system, the labeling of nanoclusters with U11 peptide can distinctly increase their affinity and accelerate their uptake by pancreatic cancer cells. Cell apoptosis staining demonstrates that, upon incorporation of the uPAR-targeted unit, the antitumor efficacy of CTSE-sensitive nanocluster AuS-U11 is significantly enhanced with respect to that of the non-targeted nanocluster AuS-PEG and the insensitive nanocluster AuC-PEG. In vivo and ex vivo optical imaging confirms the high accumulation of AuS-U11 in the in situ pancreatic tumor model. Therapeutic studies further show that the combination of active targeting for tumor tissue, enzyme-triggered drug release of 5-ALA and fluorescent dye Cy5.5 in nanoclusters AuS-U11 could achieve optimal therapeutic efficacy with endomicroscopy-guided photothermal/photodynamic therapy with minimal side effects. As a consequence, the delicate gold nanocluster concept provides a promising strategy to enhance the therapy efficiency in the most challenging PDAC treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

More Adventures in Photodynamic Therapy.

PubMed

Kessel, David

2015-07-03

Photodynamic therapy is a procedure that can provide a selective eradication of neoplastic disease if sufficient drug, light, and oxygen are available. As this description suggests, it involves the photosensitization of malignant tissues to irradiation with photons in the visible range. While not suitable for tumors at unknown loci, it can be of use for eradication of cancer at surgical margins and therapy at sites where substantial surgery might otherwise be involved. Drug development has been delayed by several factors including the reluctance of major pharmaceutical firms in the United States to invest in this technology along with some unwise approaches in the past.

The effects of photodynamic laser therapy in the treatment of marginal chronic periodontitis

NASA Astrophysics Data System (ADS)

Chifor, Radu; Badea, Iulia; Avram, Ramona; Chifor, Ioana; Badea, Mîndra Eugenia

2016-03-01

The aim of this study was to assess the effects of the antimicrobial photodynamic laser therapy performed during the treatment of deep periodontal disease by using 40 MHz high frequency ultrasonography. The periodontal data recorded during the clinical examination before each treatment session were compared with volumetric changes of the gingiva measured on periodontal ultrasound images. The results show a significant decrease of gingival tissue inflammation proved both by a significant decrease of bleeding on probing as well as by a decrease of the gingival tissues volume on sites where the laser therapy was performed. Periodontal tissues that benefit of laser therapy besides classical non-surgical treatment showed a significant clinical improvement of periodontal status. Based on these findings we were able to conclude that the antimicrobial photodynamic laser therapy applied on marginal periodontium has important anti-inflamatory effect. The periodontal ultrasonography is a method which can provide useful data for assessing the volume changes of gingival tissues, allowing a precise monitoring of marginal periodontitis.

Dual-channel red/blue fluorescence dosimetry with broadband reflectance spectroscopic correction measures protoporphyrin IX production during photodynamic therapy of actinic keratosis

NASA Astrophysics Data System (ADS)

Kanick, Stephen Chad; Davis, Scott C.; Zhao, Yan; Hasan, Tayyaba; Maytin, Edward V.; Pogue, Brian W.; Chapman, M. Shane

2014-07-01

Dosimetry for aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) photodynamic therapy of actinic keratosis was examined with an optimized fluorescence dosimeter to measure PpIX during treatment. While insufficient PpIX generation may be an indicator of incomplete response, there exists no standardized method to quantitate PpIX production at depths in the skin during clinical treatments. In this study, a spectrometer-based point probe dosimeter system was used to sample PpIX fluorescence from superficial (blue wavelength excitation) and deeper (red wavelength excitation) tissue layers. Broadband white light spectroscopy (WLS) was used to monitor aspects of vascular physiology and inform a correction of fluorescence for the background optical properties. Measurements in tissue phantoms showed accurate recovery of blood volume fraction and reduced scattering coefficient from WLS, and a linear response of PpIX fluorescence versus concentration down to 1.95 and 250 nM for blue and red excitations, respectively. A pilot clinical study of 19 patients receiving 1-h ALA incubation before treatment showed high intrinsic variance in PpIX fluorescence with a standard deviation/mean ratio of >0.9. PpIX fluorescence was significantly higher in patients reporting higher pain levels on a visual analog scale. These pilot data suggest that patient-specific PpIX quantitation may predict outcome response.

New hybrid composites for photodynamic therapy: synthesis, characterization and biological study

NASA Astrophysics Data System (ADS)

Kutsevol, N.; Naumenko, A.; Harahuts, Yu.; Chumachenko, V.; Shton, I.; Shishko, E.; Lukianova, N.; Chekhun, V.

2018-04-01

Photodynamic therapy is a procedure that uses a photosensitizing drug to apply light therapy selectively to target cancer treatment. This study is focused on a synthesis and characterization of a new hybrid nanocomposites based on the branched copolymers dextran-polyacrylamide in nonionic, D-g-PAA and anionic D-g-PAA(PE) form, with incorporated gold nanoparticles (AuNPs) and photosensitizer chlorin e6 (Ce6) simultaneously. Double polymer/AuNPs and trial polymer/AuNPs/Ce6 were studied by TEM, UV-visible, SOSG fluorescence. It was found the drastic difference for absorbance for trial nanosystems synthesized in nonionic and anionic polymers matrices. It was established that for the nanocomposite synthesised in anionic polymer matrix with the Ce6:Au mass ratio 1:10 generation of singlet oxygen (1O2) was quite close to that for free Ce6. The study of ability of this nanosystem to sensitize MT-4 cells to photodynamic damage has shown that the nanocomposite, that contained AuNPs during the synthesis of which HAuCl4:NaBH4 mass ratio was 1:2 showed higher photodynamic activity, than Ce6 itself. Nanosystem D70-g-PAA(PE)/AuNPs/Ce6 can be recommended to experiment in vivo.

A Photosensitizer-Loaded DNA Origami Nanosystem for Photodynamic Therapy.

PubMed

Zhuang, Xiaoxi; Ma, Xiaowei; Xue, Xiangdong; Jiang, Qiao; Song, Linlin; Dai, Luru; Zhang, Chunqiu; Jin, Shubin; Yang, Keni; Ding, Baoquan; Wang, Paul C; Liang, Xing-Jie

2016-03-22

Photodynamic therapy (PDT) offers an alternative for cancer treatment by using ultraviolet or visible light in the presence of a photosensitizer and molecular oxygen, which can produce highly reactive oxygen species that ultimately leading to the ablation of tumor cells by multifactorial mechanisms. However, this technique is limited by the penetration depth of incident light, the hypoxic environment of solid tumors, and the vulnerability of photobleaching reduces the efficiency of many imaging agents. In this work, we reported a cellular level dual-functional imaging and PDT nanosystem BMEPC-loaded DNA origami for photodynamic therapy with high efficiency and stable photoreactive property. The carbazole derivative BMEPC is a one- and two-photon imaging agent and photosensitizer with large two-photon absorption cross section, which can be fully excited by near-infrared light, and is also capable of destroying targets under anaerobic condition by generating reactive intermediates of Type I photodynamic reactions. However, the application of BMEPC was restricted by its poor solubility in aqueous environment and its aggregation caused quenching. We observed BMEPC-loaded DNA origami effectively reduced the photobleaching of BMEPC within cells. Upon binding to DNA origami, the intramolecular rotation of BMEPC became proper restricted, which intensify fluorescence emission and radicals production when being excited. After the BMEPC-loaded DNA origami are taken up by tumor cells, upon irradiation, BMEPC could generate free radicals and be released due to DNA photocleavage as well as the following partially degradation. Apoptosis was then induced by the generation of free radicals. This functional nanosystem provides an insight into the design of photosensitizer-loaded DNA origami for effective intracellular imaging and photodynamic therapy.

Low-dose topical 5-aminolevulinic acid photodynamic therapy in the treatment of different severity of acne vulgaris.

PubMed

Ma, Li; Xiang, Lei-Hong; Yu, Bo; Yin, Rui; Chen, Lei; Wu, Yan; Tan, Zhi-Jian; Liu, Yong-Bin; Tian, Hong-Qing; Li, Hui-Zhong; Lin, Tong; Wang, Xiu-Li; Li, Yuan-Hong; Wang, Wei-Zheng; Yang, Hui-Lan; Lai, Wei

2013-12-01

To investigate the efficacy and safety of low-concentration 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of different severity of acne vulgaris and optimize the treatment regimen. A self-controlled multicenter clinical trial was carried out in 15 centers throughout China. A total of 397 acne patients of grade II-IV received 3- or 4-session PDT treatment. 5% ALA gel was applied topically to acne lesions for 1h incubation. The lesions were irradiated by a LED light of 633 nm at dose levels of 96-120 J/cm(2). Clinical assessment was conducted before and after every treatment up to 8 weeks. The effective rate overall and of grade II, III and IV are 82.1%, 71.6%, 79.6% and 88.2%, respectively. The effective rate rises significantly proportionally to the severity of acne (P<0.01). No significant differences are found in the efficacy between patients received 3-session and 4-session PDT treatments (P>0.05). The count of inflammatory and non-inflammatory acne lesions gradually decrease after each treatment (P<0.01) and during the 8-week follow up (P<0.01 or P<0.05). Maximum efficacy is obtained at 8 weeks after the treatment completion. A low-dose topical ALA-PDT regimen using 5% ALA, 1h incubation and red light source of 3 treatment sessions is suggested as optimal scheme for the treatment of different severity of acne vulgaris in Chinese patients. Superior efficacy is found in severe cystic acne of grade IV with mild side effects. Copyright © 2013 Elsevier B.V. All rights reserved.

Photodynamic Therapy Effectively Treats Actinic Keratoses Without Pre-Illumination Incubation Time.

PubMed

Gandy, Jessica; Labadie, Brian; Bierman, Dina; Zachary, Christopher

2017-03-01

BACKGROUND: Actinic keratoses (AKs) are dysplastic lesions of the epidermis that have the potential to progress to non-melanoma skin cancers (NMSC). Traditional photodynamic therapy (PDT) requires a pre-illumination incubation time, which adds to overall in-office time and has been linked to pain. Our group has found a novel protocol to effectively treat AKs with PDT that eliminates the pre-illumination incubation period and uses 2 back-to-back cycles of 16 minute 40 seconds.

METHODS: The patient was prepped with soapy water and isopropyl alcohol, and thick AKs were descaled with a curette. Next, 5-aminolevulinic acid (ALA) was applied to the treatment areas and the patient was immediately placed under the blue light for 33 minutes and 20 seconds (two cycles of 16m/40s).

RESULTS: During therapy, the patient reported no pain. At one week, treated areas revealed a good reaction. The procedure was repeated at one month to treat residual AKs. At a 4-month follow-up, the patient's face and scalp showed near clearance of any AKs.

CONCLUSION: During PDT, the photosensitizer aminolevulinic acid (ALA), or in Europe methyl aminolevulinate (MAL), is utilized as a synthetic precursor that preferentially accumulates in dysplastic cells. The precursor then converts to PpIX via the heme pathway and causes apoptosis of the cells when excited, most commonly by either blue-violet (400-430 nm) or red (630-635 nm) light. Shorter incubation times are associated with reduced pain because less PpIX will have accumulated in the treated tissue by the start of the exposure to the light. The doubling of the light exposure time allows comparable levels of the photosensitizing molecule to accumulate and be activated so as to produce an equivalent reaction. The associated reduction in pain along with a more convenient treatment schedule makes this PDT protocol more tolerable and convenient to some patients.

J Drugs Dermatol. 2017;16(3):275-278.

Mitochondria-targeted cationic porphyrin-triphenylamine hybrids for enhanced two-photon photodynamic therapy.

PubMed

Hammerer, Fabien; Poyer, Florent; Fourmois, Laura; Chen, Su; Garcia, Guillaume; Teulade-Fichou, Marie-Paule; Maillard, Philippe; Mahuteau-Betzer, Florence

2018-01-01

The proof of concept for two-photon activated photodynamic therapy has already been achieved for cancer treatment but the efficiency of this approach still heavily relies on the availability of photosensitizers combining high two-photon absorption and biocompatibility. In this line we recently reported on a series of porphyrin-triphenylamine hybrids which exhibit high singlet oxygen production quantum yield as well as high two-photon absorption cross-sections but with a very poor cellular internalization. We present herein new photosensitizers of the same porphyrin-triphenylamine hybrid series but bearing cationic charges which led to strongly enhanced water solubility and thus cellular penetration. In addition the new compounds have been found localized in mitochondria that are preferential target organelles for photodynamic therapy. Altogether the strongly improved properties of the new series combined with their specific mitochondrial localization lead to a significantly enhanced two-photon activated photodynamic therapy efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

The sensitivity of normal brain and intracranially implanted VX2 tumour to interstitial photodynamic therapy.

PubMed Central

Lilge, L.; Olivo, M. C.; Schatz, S. W.; MaGuire, J. A.; Patterson, M. S.; Wilson, B. C.

1996-01-01

The applicability and limitations of a photodynamic threshold model, used to describe quantitatively the in vivo response of tissues to photodynamic therapy, are currently being investigated in a variety of normal and malignant tumour tissues. The model states that tissue necrosis occurs when the number of photons absorbed by the photosensitiser per unit tissue volume exceeds a threshold. New Zealand White rabbits were sensitised with porphyrin-based photosensitisers. Normal brain or intracranially implanted VX2 tumours were illuminated via an optical fibre placed into the tissue at craniotomy. The light fluence distribution in the tissue was measured by multiple interstitial optical fibre detectors. The tissue concentration of the photosensitiser was determined post mortem by absorption spectroscopy. The derived photodynamic threshold values for normal brain are significantly lower than for VX2 tumour for all photosensitisers examined. Neuronal damage is evident beyond the zone of frank necrosis. For Photofrin the threshold decreases with time delay between photosensitiser administration and light treatment. No significant difference in threshold is found between Photofrin and haematoporphyrin derivative. The threshold in normal brain (grey matter) is lowest for sensitisation by 5 delta-aminolaevulinic acid. The results confirm the very high sensitivity of normal brain to porphyrin photodynamic therapy and show the importance of in situ light fluence monitoring during photodynamic irradiation. Images Figure 1 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8562339

Nanoparticle-based photodynamic therapy on non-melanoma skin cancer

NASA Astrophysics Data System (ADS)

Fanjul-Vélez, F.; Arce-Diego, J. L.

2018-02-01

There are several advantages of Photodynamic Therapy (PDT) for nonmelanoma skin cancer treatment compared to conventional treatment techniques such as surgery, radiotherapy or chemotherapy. Among these advantages its noninvasive nature, the use of non ionizing radiation and its high selectivity can be mentioned. Despite all these advantages, the therapeutic efficiency of the current clinical protocol is not complete in all the patients and depends on the type of pathology. An adequate dosimetry is needed in order to personalize the protocol. There are strategies that try to overcome the current PDT shortcomings, such as the improvement of the photosensitizer accumulation in the target tissue, optical radiation distribution optimization or photochemical reactions maximization. These strategies can be further complemented by the use of nanostructures with conventional PDT. Customized dosimetry for nanoparticle-based PDT requires models in order to adjust parameters of different nature to get an optimal tumor removal. In this work, a predictive model of nanoparticle-based PDT is proposed and analyzed. Dosimetry in nanoparticle-based PDT is going to be influenced by photosensitizer-nanoparticle distribution in the malignant tissue, its influence in the optical radiation distribution and the subsequent photochemical reactions. Nanoparticles are considered as photosensitizer carriers on several types of non-melanoma skin cancer. Shielding effects are taken into account. The results allow to compare the estimated treatment outcome with and without nanoparticles.

The photosensitizer talaporfinum caused microvascular embolization for photodynamic therapy

NASA Astrophysics Data System (ADS)

Li, Liming; Aizawa, Katsuo

2005-07-01

Photodynamic therapy (PDT) has been evolving rapidly in the recent years. A second-generation Photosensitizer mono-1-aspartyl chlorine 6 (Talaporfin / Npe6 / ME2906, Japan Meiji Seika, Ltd.) has been sanctified for the lung cancer clinical PDT by the Japan Ministry of Health, Labor and Welfare. In this paper, Talaporfin was injected to the implant cancer of a mouse a Talaporfin dose of 5mg/kg through intravenous. After 6 hours, the fluorescence images of the mouse were observed with a microscope and a 664 nm diode laser. Effects of therapy were clarified using the different irradiation energies of the laser (50, 100, 200 J/cm2). Both in plasma and in cancer, the concentrations of Talaporfin were analyzed using High Performance Liquid Chromatography (HPLC). Authors find that the higher concentrations of Talaporfin in plasma, the better PDD effect. It is experimentally verified that local microvascular embolisms in the cancer are formed for photodynamic therapy after the Talaporfin injection and the laser irradiation.

Preclinical in vitro and in vivo studies to examine the potential use of photodynamic therapy in the treatment of osteomyelitis

NASA Astrophysics Data System (ADS)

Bisland, Stuart K.; Chien, Claudia; Wilson, Brian C.; Burch, Shane

2005-04-01

Osteomyelitis can lead to severe morbidity and even death resulting from an acute or chronic inflammation of the bone and contiguous structures due to fungal or bacterial infection. Incidence approximates 1 in 1,000 neonates and 1 in 5,000 children in the United States annually and increases up to 0.36% and 16% in adults with diabetes or sickle cell anaemia, respectively. Current regiments of treatment include antibiotics and/or surgery. However, the increasing number of antibiotic resistant pathogens suggests that alternate strategies are required. We are investigating photodynamic therapy (PDT) as one such alternate treatment for osteomyelitis using a bioluminescent strain of biofilm-producing staphylococcus aureus (SA) grown onto kirschner wires (K-wire). SA-coated K-wires were exposed to methylene blue (MB) or 5-aminolevulinic acid (ALA)-mediated PDT either in vitro or following implant into the tibial medullary cavity of Sprague-Dawley rats. The progression of SA biofilm was monitored non-invasively using bioluminescence and expressed as a percentage of the signal for each sample immediately prior to treatment. SA infections were subject to PDT 10 days post inoculation. Treatment comprised administration of ALA (300 mg/Kg) intraperitoneally followed 4 hr later by light (635 +/- 10 nm; 38 or 75 J/cm2) delivered transcutaneously via an optical fiber placed onto the tibia. In vitro, MB and ALA displayed similar cell kill with >= 4log10 cell kill. In vivo, ALA-mediated PDT inhibited biofilm implants in bone. These results confirm that MB or ALA-mediated PDT have potential to treat SA cultures grown in vitro or in vivo using an animal model of osteomyelitis.

Photodynamic therapy in dentistry: a literature review.

PubMed

Gursoy, Hare; Ozcakir-Tomruk, Ceyda; Tanalp, Jale; Yilmaz, Selçuk

2013-05-01

The purpose of this review was to summarize recent developments regarding photodynamic therapy (PDT) in the field of dentistry. A review of pertinent literature was carried out in PubMED to determine the current position of PDT applications in dentistry. One hundred thirteen relevant articles were retrieved from PubMED by inserting the keywords "photodynamic therapy", "dentistry", "periodontology", "oral surgery", and "endodontics". It is anticipated that this overview will create a specific picture in the practitioner's mind regarding the current status and use of PDT. In spite of different results and suggestions brought about by different researchers, PDT can be considered as a promising and less invasive technique in dentistry. PDT seems to be an effective tool in the treatment of localized and superficial infections. Within the limitations of the present review, it can be concluded that although PDT cannot replace antimicrobial therapy at its current stage, it may be used as an adjunctive tool for facilitating the treatment of oral infections. Oral infections (such as mucosal and endodontic infections, periodontal diseases, caries, and peri-implantitis) are among the specific targets where PDT can be applied. Further long-term clinical studies are necessary in establishing a more specific place of the technique in the field of dentistry.

Photodynamic therapy improves the ultraviolet-irradiated hairless mice skin

NASA Astrophysics Data System (ADS)

Jorge, Ana Elisa S.; Hamblin, Michael R.; Parizotto, Nivaldo A.; Kurachi, Cristina; Bagnato, Vanderlei S.

2014-03-01

Chronic exposure to ultraviolet (UV) sunlight causes premature skin aging. In light of this fact, photodynamic therapy (PDT) is an emerging modality for treating cancer and other skin conditions, however its response on photoaged skin has not been fully illustrated by means of histopathology. For this reason, the aim of this study was analyze whether PDT can play a role on a mouse model of photoaging. Hence, SKH-1 hairless mice were randomly allocated in two groups, UV and UV/PDT. The mice were daily exposed to an UV light source (280-400 nm: peak at 350 nm) for 8 weeks followed by a single PDT session using 20% 5-aminolevulinic acid (ALA) topically. After the proper photosensitizer accumulation within the tissue, a non-coherent red (635 nm) light was performed and, after 14 days, skin samples were excised and processed for light microscopy, and their sections were stained with hematoxylin-eosin (HE) and Masson's Trichrome. As a result, we observed a substantial epidermal thickening and an improvement in dermal collagen density by deposition of new collagen fibers on UV/PDT group. These findings strongly indicate epidermal and dermal restoration, and consequently skin restoration. In conclusion, this study provides suitable evidences that PDT improves the UV-irradiated hairless mice skin, supporting this technique as an efficient treatment for photoaged skin.

Apoptosis triggered by pyropheophorbide-α methyl ester-mediated photodynamic therapy in a giant cell tumor in bone

NASA Astrophysics Data System (ADS)

Li, K.-T.; Zhang, J.; Duan, Q.-Q.; Bi, Y.; Bai, D.-Q.; Ou, Y.-S.

2014-06-01

A giant cell tumor in bone is the common primary bone tumor with aggressive features, occurring mainly in young adults. Photodynamic therapy is a new therapeutic technique for tumors. In this study, we investigated the effects of Pyropheophorbide-α methyl ester (MPPa)-mediated photodynamic therapy on the proliferation of giant cell tumor cells and its mechanism of action. Cell proliferation was evaluated using an MTT assay. Cellular apoptosis was detected by Hoechst nuclear staining, and flow cytometric assay. Mitochondrial membrane potential changes and cytochrome c, caspase-9, caspase-3, and Bcl-2 expression was assessed. Finally, we found that MPPa-mediated photodynamic therapy could effectively suppress the proliferation of human giant cell tumor cells and induce apoptosis. The mitochondrial pathway was involved in the MPPa-photodynamic therapy-induced apoptosis.

Photodynamic inactivation of the models Mycobacterium phlei and Mycobacterium smegmatis in vitro

NASA Astrophysics Data System (ADS)

Bruce-Micah, R.; Gamm, U.; Hüttenberger, D.; Cullum, J.; Foth, H.-J.

2009-07-01

Photodynamic inactivation (PDI) of bacterial strains presents an attractive potential alternative to antibiotic therapies. Success is dependent on the effective accumulation in bacterial cells of photochemical substances called photosensitizers, which are usually porphyrins or their derivatives. The kinetics of porphyrin synthesis after treatment with the precursor ALA and the accumulation of the Chlorin e6 and the following illumination were studied. The goal was to estimate effectivity of the destructive power of these PS in vitro in respect of the physiological states of Mycobacteria. So the present results examine the cell destruction by PDI using ALA-induced Porphyrins and Chlorin e6 accumulated in Mycobacterium phlei and Mycobacterium smegmatis, which serve as models for the important pathogens Mycobacterium tuberculosis, Mycobacterium leprae and Mycobacterium bovis. We could show that both Mycobacterium after ALA and Chlorin e6 application were killed by illumination with light of about 662 nm. A reduction of about 97% could be reached by using a lightdose of 70 mW/cm2.

Effect of light polarization on the efficiency of photodynamic therapy of basal cell carcinomas: an in vitro cellular study.

PubMed

JalalKamali, M; Nematollahi-Mahani, S N; Shojaei, M; Shamsoddini, A; Arabpour, N

2018-02-01

In an in vitro study, the effect of light polarization on the efficiency of 5-aminolaevulinic acid (ALA) photodynamic therapy (PDT) of basal cell carcinoma (BCC) was investigated. Three states of light polarization (non-polarized, linearly polarized, and circularly polarized) were considered. Cells were exposed to green (532 pm 20 nm) irradiation from light emitting diodes. Cell survival was measured by the colorimetric assay (WST-1) and Trypan blue staining. The colorimetric assay showed a pronounced decrease in the cell viability (up to 30%) using polarized light compared to the non-polarized one in the wavelength region used. Similar results were obtained by the cell counting method (20-30% increase in cell death). The observed effect was dependent on the concentration of photosensitizer. The effect is more expressed in the case of linearly polarized light compared to the circularly polarized one. Results show that the use of polarized light increases the efficiency of in vitro ALA-PDT of BCC. Utilizing polarized light, it is possible to obtain the same effect from PDT by lower concentrations of photosensitizer. Additionally, the concentration dependency of PDT response and photo-bleaching is also reduced.

Blue laser system for photo-dynamic therapy

NASA Astrophysics Data System (ADS)

Dabu, R.; Carstocea, B.; Blanaru, C.; Pacala, O.; Stratan, A.; Ursu, D.; Stegaru, F.

2007-03-01

A blue laser system for eye diseases (age related macular degeneration, sub-retinal neo-vascularisation in myopia and presumed ocular histoplasmosis syndrome - POHS) photo-dynamic therapy, based on riboflavin as photosensitive substance, has been developed. A CW diode laser at 445 nm wavelength was coupled through an opto-mechanical system to the viewing path of a bio-microscope. The laser beam power in the irradiated area is adjustable between 1 mW and 40 mW, in a spot of 3-5 mm diameter. The irradiation time can be programmed in the range of 1-19 minutes. Currently, the laser system is under clinic tests.

Improve efficacy of topical ALA-PDT by calcipotriol through up-regulation of coproporphyrinogen oxidase.

PubMed

Yang, Deng-Fu; Chen, Jia-Haur; Chiang, Chun-Pin; Huang, Zheng; Lee, Jeng-Woei; Liu, Chung-Ji; Chang, Junn-Liang; Hsu, Yih-Chih

2014-09-01

Topical 5-aminolevulinic acid-mediated photodynamic therapy (topical ALA-PDT) is effective for treating oral precancerous lesions. The aim of this in vivo and in vitro study was to examine whether the efficacy of topical ALA-PDT could be further improved by calcipotriol (CAL). Precancerous lesions in the buccal pouch of hamsters were induced by dimethylbenz(a)anthracene (DMBA). Lesions were treated with multiple topical ALA-PDT with or without CAL pretreatment. ALA-induced protoporphyrine IX (PpIX) was monitored by in situ fluorescence measurement. The effect of CAL on heme-related enzymes (CPOX, PPOX, and FECH) were examined in an in vitro model using human squamous cell carcinoma (SCC) cells (SCC4, SAS) using Western blots. Fluorescence spectroscopy revealed that PpIX reached its peak level in precancerous epithelial cells of buccal pouch at 2.5 or 3.5h without or with CAL pretreatment, respectively. Both treatment regimens showed similar response rates, but the complete response was achieved after 5 times of ALA-PDT and 3 times of CAL-ALA-PDT (p<0.001). Pretreatment of SCC cells with 10(-8) or 10(-7)M CAL could result in a significant cell death (p<0.05) and an elevation of CPOX protein level. Topical CAL can improve the efficacy of ALA-PDT in treating precancerous lesions, likely through the increase in CPOX level and in PpIX production. Copyright © 2014 Elsevier B.V. All rights reserved.

Differential antioxidant defense and detoxification mechanisms in photodynamically stressed rice plants treated with the deregulators of porphyrin biosynthesis, 5-aminolevulinic acid and oxyfluorfen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phung, Thu-Ha; Jung, Sunyo, E-mail: sjung@knu.ac.kr

This study focuses on differential molecular mechanisms of antioxidant and detoxification systems in rice plants under two different types of photodynamic stress imposed by porphyrin deregulators, 5-aminolevulinic acid (ALA) and oxyfluorfen (OF). The ALA-treated plants with white necrosis exhibited a greater decrease in photochemical quantum efficiency, F{sub v}/F{sub m}, as well as a greater increase in activity of superoxide dismutase, compared to the OF-treated plants. By contrast, the brown necrosis in OF-treated plants resulted in not only more widely dispersed H{sub 2}O{sub 2} production and greater increases in H{sub 2}O{sub 2}-decomposing enzymes, catalase and peroxidase, but also lower ascorbate redoxmore » state. In addition, ALA- and OF-treated plants markedly up-regulated transcript levels of genes involved in detoxification processes including transport and movement, cellular homeostasis, and xenobiotic conjugation, with prominent up-regulation of serine/threonine kinase and chaperone only in ALA-treated plants. Our results demonstrate that different photodynamic stress imposed by ALA and OF developed differential actions of antioxidant enzymes and detoxification. Particularly, detoxification system may play potential roles in plant protection against photodynamic stress imposed by porphyrin deregulators, thereby contributing to alleviation of photodynamic damage. - Highlights: • We employ two different types of photodynamic stress, white and brown necrosis. • We examine molecular mechanisms of antioxidative and detoxification systems. • ALA and OF develop differential actions of antioxidant and detoxification systems. • Coordinated mechanism of antioxidants and detoxification works against toxic ROS. • Detoxification system plays critical roles in protection against photodynamic stress.« less

Low-cost photodynamic therapy devices for global health settings: Characterization of battery-powered LED performance and smartphone imaging in 3D tumor models

NASA Astrophysics Data System (ADS)

Hempstead, Joshua; Jones, Dustin P.; Ziouche, Abdelali; Cramer, Gwendolyn M.; Rizvi, Imran; Arnason, Stephen; Hasan, Tayyaba; Celli, Jonathan P.

2015-05-01

A lack of access to effective cancer therapeutics in resource-limited settings is implicated in global cancer health disparities between developed and developing countries. Photodynamic therapy (PDT) is a light-based treatment modality that has exhibited safety and efficacy in the clinic using wavelengths and irradiances achievable with light-emitting diodes (LEDs) operated on battery power. Here we assess low-cost enabling technology to extend the clinical benefit of PDT to regions with little or no access to electricity or medical infrastructure. We demonstrate the efficacy of a device based on a 635 nm high-output LED powered by three AA disposable alkaline batteries, to achieve strong cytotoxic response in monolayer and 3D cultures of A431 squamous carcinoma cells following photosensitization by administering aminolevulinic acid (ALA) to induce the accumulation of protoporphyrin IX (PpIX). Here we characterize challenges of battery-operated device performance, including battery drain and voltage stability specifically over relevant PDT dose parameters. Further motivated by the well-established capacity of PDT photosensitizers to serve as tumour-selective fluorescence contrast agents, we demonstrate the capability of a consumer smartphone with low-cost add-ons to measure concentration-dependent PpIX fluorescence. This study lays the groundwork for the on-going development of image-guided ALA-PDT treatment technologies for global health applications.

Low-cost photodynamic therapy devices for global health settings: Characterization of battery-powered LED performance and smartphone imaging in 3D tumor models

PubMed Central

Hempstead, Joshua; Jones, Dustin P.; Ziouche, Abdelali; Cramer, Gwendolyn M.; Rizvi, Imran; Arnason, Stephen; Hasan, Tayyaba; Celli, Jonathan P.

2015-01-01

A lack of access to effective cancer therapeutics in resource-limited settings is implicated in global cancer health disparities between developed and developing countries. Photodynamic therapy (PDT) is a light-based treatment modality that has exhibited safety and efficacy in the clinic using wavelengths and irradiances achievable with light-emitting diodes (LEDs) operated on battery power. Here we assess low-cost enabling technology to extend the clinical benefit of PDT to regions with little or no access to electricity or medical infrastructure. We demonstrate the efficacy of a device based on a 635 nm high-output LED powered by three AA disposable alkaline batteries, to achieve strong cytotoxic response in monolayer and 3D cultures of A431 squamous carcinoma cells following photosensitization by administering aminolevulinic acid (ALA) to induce the accumulation of protoporphyrin IX (PpIX). Here we characterize challenges of battery-operated device performance, including battery drain and voltage stability specifically over relevant PDT dose parameters. Further motivated by the well-established capacity of PDT photosensitizers to serve as tumour-selective fluorescence contrast agents, we demonstrate the capability of a consumer smartphone with low-cost add-ons to measure concentration-dependent PpIX fluorescence. This study lays the groundwork for the on-going development of image-guided ALA-PDT treatment technologies for global health applications. PMID:25965295

Low-cost photodynamic therapy devices for global health settings: Characterization of battery-powered LED performance and smartphone imaging in 3D tumor models.

PubMed

Hempstead, Joshua; Jones, Dustin P; Ziouche, Abdelali; Cramer, Gwendolyn M; Rizvi, Imran; Arnason, Stephen; Hasan, Tayyaba; Celli, Jonathan P

2015-05-12

A lack of access to effective cancer therapeutics in resource-limited settings is implicated in global cancer health disparities between developed and developing countries. Photodynamic therapy (PDT) is a light-based treatment modality that has exhibited safety and efficacy in the clinic using wavelengths and irradiances achievable with light-emitting diodes (LEDs) operated on battery power. Here we assess low-cost enabling technology to extend the clinical benefit of PDT to regions with little or no access to electricity or medical infrastructure. We demonstrate the efficacy of a device based on a 635 nm high-output LED powered by three AA disposable alkaline batteries, to achieve strong cytotoxic response in monolayer and 3D cultures of A431 squamous carcinoma cells following photosensitization by administering aminolevulinic acid (ALA) to induce the accumulation of protoporphyrin IX (PpIX). Here we characterize challenges of battery-operated device performance, including battery drain and voltage stability specifically over relevant PDT dose parameters. Further motivated by the well-established capacity of PDT photosensitizers to serve as tumour-selective fluorescence contrast agents, we demonstrate the capability of a consumer smartphone with low-cost add-ons to measure concentration-dependent PpIX fluorescence. This study lays the groundwork for the on-going development of image-guided ALA-PDT treatment technologies for global health applications.

Folate and Heptamethine Cyanine Modified Chitosan-Based Nanotheranostics for Tumor Targeted Near-Infrared Fluorescence Imaging and Photodynamic Therapy.

PubMed

Zhang, Yingying; Lv, Tingting; Zhang, Huijuan; Xie, Xiaodong; Li, Ziying; Chen, Haijun; Gao, Yu

2017-07-10

Folate (FA) and heptamethine cyanine (Cy7)-modified chitosan (CF7) was synthesized by click chemistry and its self-assembled nanoparticles (CF7Ns) were developed for tumor-specific imaging and photodynamic therapy. The characterization spectrum confirmed CF7 had a good FA and Cy7 conjugation efficacy. The diameter of CF7Ns measured by DLS was about 291.6 nm, and the morphology observed with AFM showed filamentous clusters of particles. The results of targeting ability of CF7Ns demonstrated enhanced targeting behaviors of CF7Ns compared with non-FA-modified nanoparticles C7Ns in FA receptor-positive HeLa cells. The cytotoxicity and cell apoptosis assay showed that CF7Ns under near-infrared light irradiation led to more apoptotic cell death in HeLa cells to improve the therapeutic efficacy. The mechanisms of the photodynamic effects of CF7Ns were demonstrated through measurement of intracellular reactive oxygen species and the apoptosis-related cytokines. These results suggested that CF7Ns are promising tumor targeting carriers for simultaneous fluorescence imaging and photodynamic therapy.

Successful treatment of recalcitrant folliculitis barbae and pseudofolliculitis barbae with photodynamic therapy.

PubMed

Diernaes, Jon Erik Fraes; Bygum, Anette

2013-12-01

Folliculitis and pseudofolliculitis barbae typically affects men with curly hair who shave too close. Treatment modalities vary in effectiveness and include improved hair removal methods, topical corticosteroids, topical and oral antibiotics, and retinoids as well as laser surgery. We report a novel treatment of recalcitrant pseudofolliculitis barbae and confirm effectiveness in recalcitrant folliculitis in a 58-year old man who responded completely following photodynamic therapy with methyl aminolevulinate. Photodynamic therapy should be considered in recalcitrant folliculitis and pseudofolliculitis barbae. Copyright © 2013 Elsevier B.V. All rights reserved.

Combination photodynamic therapy using 5-fluorouracil and aminolevulinate enhances tumor-selective production of protoporphyrin IX and improves treatment efficacy of squamous skin cancers and precancers

NASA Astrophysics Data System (ADS)

Maytin, Edward V.; Anand, Sanjay

2016-03-01

In combination photodynamic therapy (cPDT), a small-molecule drug is used to modulate the physiological state of tumor cells prior to giving aminolevulinate (ALA; a precursor for protoporphyrin IX, PpIX). In our laboratory we have identified three agents (methotrexate, 5-fluorouracil, and vitamin D) that can enhance therapeutic effectiveness of ALAbased photodynamic therapy for cutaneous squamous cell carcinoma (SCC). However, only one (5-fluorouracil; 5-FU) is FDA-approved for skin cancer management. Here, we describe animal and human studies on 5-FU mechanisms of action, in terms of how 5-FU pretreatment leads to enhanced PpIX accumulation and improves selectivity of ALA-PDT treatment. In A431 subcutaneous tumors in mice, 5-FU changed expression of heme enzyme (upregulating coproporphyrinogen oxidase, and down-regulating ferrochelatase), inhibited tumor cell proliferation (Ki-67), enhanced differentiation (E-cadherin), and led to strong, tumor-selective increases in apoptosis. Interestingly, enhancement of apoptosis by 5-FU correlated strongly with an increased accumulation of p53 in tumor cells that persisted for 24 h post- PDT. In a clinical trial using a split-body, bilaterally controlled study design, human subjects with actinic keratoses (AK; preneoplastic precursors of SCC) were pretreated on one side of the face, scalp, or forearms with 5-FU cream for 6 days, while the control side received no 5-FU. On the seventh day, the levels of PpIX in 4 test lesions were measured by noninvasive fluorescence dosimetry, and then all lesions were treated with PDT using methyl-aminolevulinate (MAL) and red light (635 nm). Relative amounts of PpIX were found to be increased ~2-fold in 5-FU pretreated lesions relative to controls. At 3 months after PDT, the overall clinical response to PDT (reduction in lesion counts) was 2- to 3-fold better for the 5-FU pretreated lesions, a clinically important result. In summary, 5-FU is a useful adjuvant to aminolevulinate-based PDT

Evaluation of antitumor efficiency of experimental interstitial photodynamic therapy on the model of M1 sarcoma.

PubMed

Skugareva, O A; Kaplan, M A; Malygina, A I; Mikhailovskaya, A A

2009-11-01

Antitumor efficiency of interstitial photodynamic therapy was evaluated in experiments on outbred albino rats with implanted M-1 sarcoma. Interstitial photodynamic therapy was carried out using one diffusor at different output power and duration of exposure. The percentage of complete regression of the tumors increased with increasing exposure parameters.

Evaluation of the efficacy of photodynamic therapy for the treatment of actinic cheilitis.

PubMed

Chaves, Yuri N; Torezan, Luis Antonio; Lourenço, Silvia Vanessa; Neto, Cyro Festa

2017-01-01

Actinic cheilitis (AC) is a lip intraepithelial neoplasia, whose cells present alterations similar to those presented by invasive squamous cell carcinomas (SCCs). To conduct clinical and laboratory evaluation by histopathology and immunohistochemistry of the efficacy of actinic cheilitis treatment using photodynamic therapy (PDT) with methyl aminolevulinate (MAL) and noncoherent red light. Patients with actinic cheilitis detected by histopathological examination were submitted to two sessions of photodynamic therapy with a two-week interval between them. They were examined immediately after the sessions, four, six, and twelve weeks after beginning treatment when a new biopsy was carried out. Clinical histopathological and immunohistochemical parameters were evaluated before and after treatment. Of the 23 patients who underwent biopsy, 16 completed two photodynamic therapy sessions and the material of one patient was insufficient for immunohistochemistry. Complete clinical response was achieved in 62.5% (10 of 16 patients) and 37.5% still remained with clinical evidence of AC. In spite of this, no case of cure by histopathological analysis was found. There was no significant statistical change among the values of Ki-67, survivin, and p53 observed before and after treatment. Photodynamic therapy, as carried out in this trial, was not an efficacious therapeutic option for treating patients with actinic cheilitis included in this sample. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Dual-channel red/blue fluorescence dosimetry with broadband reflectance spectroscopic correction measures protoporphyrin IX production during photodynamic therapy of actinic keratosis

PubMed Central

Kanick, Stephen Chad; Davis, Scott C.; Zhao, Yan; Hasan, Tayyaba; Maytin, Edward V.; Pogue, Brian W.; Chapman, M. Shane

2014-01-01

Abstract. Dosimetry for aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) photodynamic therapy of actinic keratosis was examined with an optimized fluorescence dosimeter to measure PpIX during treatment. While insufficient PpIX generation may be an indicator of incomplete response, there exists no standardized method to quantitate PpIX production at depths in the skin during clinical treatments. In this study, a spectrometer-based point probe dosimeter system was used to sample PpIX fluorescence from superficial (blue wavelength excitation) and deeper (red wavelength excitation) tissue layers. Broadband white light spectroscopy (WLS) was used to monitor aspects of vascular physiology and inform a correction of fluorescence for the background optical properties. Measurements in tissue phantoms showed accurate recovery of blood volume fraction and reduced scattering coefficient from WLS, and a linear response of PpIX fluorescence versus concentration down to 1.95 and 250 nM for blue and red excitations, respectively. A pilot clinical study of 19 patients receiving 1-h ALA incubation before treatment showed high intrinsic variance in PpIX fluorescence with a standard deviation/mean ratio of >0.9. PpIX fluorescence was significantly higher in patients reporting higher pain levels on a visual analog scale. These pilot data suggest that patient-specific PpIX quantitation may predict outcome response. PMID:24996661

Three-dimensional in vitro cancer spheroid models for Photodynamic Therapy: Strengths and Opportunities

NASA Astrophysics Data System (ADS)

Evans, Conor

2015-03-01

Three dimensional, in vitro spheroid cultures offer considerable utility for the development and testing of anticancer photodynamic therapy regimens. More complex than monolayer cultures, three-dimensional spheroid systems replicate many of the important cell-cell and cell-matrix interactions that modulate treatment response in vivo. Simple enough to be grown by the thousands and small enough to be optically interrogated, spheroid cultures lend themselves to high-content and high-throughput imaging approaches. These advantages have enabled studies investigating photosensitizer uptake, spatiotemporal patterns of therapeutic response, alterations in oxygen diffusion and consumption during therapy, and the exploration of mechanisms that underlie therapeutic synergy. The use of quantitative imaging methods, in particular, has accelerated the pace of three-dimensional in vitro photodynamic therapy studies, enabling the rapid compilation of multiple treatment response parameters in a single experiment. Improvements in model cultures, the creation of new molecular probes of cell state and function, and innovations in imaging toolkits will be important for the advancement of spheroid culture systems for future photodynamic therapy studies.

Antitumor effects evaluation of a novel porphyrin derivative in photodynamic therapy.

PubMed

Li, Jian-Wei; Wu, Zhong-Ming; Magetic, Davor; Zhang, Li-Jun; Chen, Zhi-Long

2015-12-01

In this paper, the antitumor activity of a novel porphyrin-based photosensitizer 5,10,15,20-tetrakis[(5-diethylamino)pentyl] porphyrin (TDPP) was reported in vitro and in vivo. The photophysical and cellular properties of TDPP were investigated. The singlet oxygen generation quantum yield of TDPP was detected; it showed a high singlet oxygen quantum yield of 0.52. The intracellular distribution of photosensitizer was detected with laser scanning confocal microscopy. The efficiency of TDPP-photodynamic therapy (PDT) in vitro was analyzed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and in situ trypan blue exclusion test. Treated with a 630-nm laser, TDPP can kill cultured human esophageal cancer cell line (Eca-109) cells and reduce the growth of Eca-109 xenograft tumors significantly in BABL/c nude mice. And histopathological study was also used to confirm the antitumor effect. It has the perspective to be developed as a new antitumor drug in photodynamic therapy and deserves further investigation.

Biodistribution and photodynamic effect of protoporphyrin IX in rat urinary bladders after intravesical instillation of 5-aminolaevulinic acid

NASA Astrophysics Data System (ADS)

Chang, Shi-Chung; MacRobert, Alexander J.; Bown, Stephen G.

1995-03-01

Photodynamic therapy (PDT) has considerable potential for the treatment of superficial bladder neoplasia. Complications such as scarring of the detrusor muscle and prolonged cutaneous photosensitivity may be reduced by using the new photosensitizer precursor, 5- aminolaevulinic acid (ALA). After instillation of ALA, the concentration, pH, and time of bladder retention of ALA solution were found to be the key factors to a satisfactory PpIX buildup in the mucosa. The optimum PpIX fluorescence intensity ratio between mucosa and muscle layer is 10 to 1 with a pH 5.5, 1% ALA solution retained for 5 hours. Higher concentration resulted in more mucosal PpIX formation, but less selectivity. Unbuffered ALA was unsuitable for bladder instillation. Two days after laser treatment with 25 J/cm2 at 630 nm with optimal sensitization, typical histological findings were urothelial sloughing and lamina propria edema without obvious muscle damage. After 7 days, recovery of the urothelium was almost complete and fibroblast infiltration was minimal. ALA induced PpIX after bladder instillation may be an appropriate photosensitizer for future management of superficial bladder cancer.

Current status of photodynamic therapy for human cancer

NASA Astrophysics Data System (ADS)

Marcus, Stuart L.

1991-06-01

Although clinical trials in photodynamic therapy (PDT) have been ongoing for over a decade, attempts to apply for approval of the therapy from boards of health for general use began only in 1989. The steps which are being taken to approve PDT for the treatment of endobronchial lung cancer, superficial bladder cancer and esophageal cancer are described. Technological innovations which have been suggested as increasing the ease of use of PDT as a therapeutic modality are briefly discussed.

Perturbed porphyrin biosynthesis contributes to differential herbicidal symptoms in photodynamically stressed rice (Oryza sativa) treated with 5-aminolevulinic acid and oxyfluorfen.

PubMed

Phung, Thu-Ha; Jung, Sunyo

2014-11-01

This paper focuses on the molecular mechanism of deregulated porphyrin biosynthesis in rice plants under photodynamic stress imposed by an exogenous supply of 5-aminolevulinic acid (ALA) and oxyfluorfen (OF). Plants treated with 5 mM ALA or 50 µM OF exhibited differential herbicidal symptoms as characterized by white and brown necrosis, respectively, with substantial increases in cellular leakage and malondialdehyde production. Protoporphyrin IX accumulated to higher levels after 1 day of ALA and OF treatment, whereas it decreased to the control level after 2 days of ALA treatment. Plants responded to OF by greatly decreasing the levels of Mg-protoporphyrin IX (MgProto IX), MgProto IX methyl ester, and protochlorophyllide to levels lower than control, whereas their levels drastically increased 1 day after ALA treatment and then disappeared 2 days after the treatment. Enzyme activity and transcript levels of HEMA1, GSA and ALAD for ALA synthesis greatly decreased in ALA- and OF-treated plants. Transcript levels of PPO1, CHLH, CHLI, and PORB genes involving Mg-porphyrin synthesis continuously decreased in ALA- and OF-treated plants, with greater decreases in ALA-treated plants. By contrast, up-regulation of FC2 and HO2 genes in Fe-porphyrin branch was noticeable in ALA and OF-treated plants 1 day and 2 days after the treatments, respectively. Decreased transcript levels of nuclear-encoded genes Lhcb1, Lhcb6, and RbcS were accompanied by disappearance of MgProto IX in ALA- and OF-treated plants after 2 days of the treatments. Under photodynamic stress imposed by ALA and OF, tight control of porphyrin biosynthesis prevents accumulation of toxic metabolic intermediates not only by down-regulation of their biosynthesis but also by photodynamic degradation. The up-regulation of FC2 and HO2 also appears to compensate for the photodynamic stress-induced damage. Copyright © 2014 Elsevier Inc. All rights reserved.

Comparative study of trichloroacetic acid vs. photodynamic therapy with topical 5-aminolevulinic acid for actinic keratosis of the scalp.

PubMed

Di Nuzzo, Sergio; Cortelazzi, Chiara; Boccaletti, Valeria; Zucchi, Alfredo; Conti, Maria Luisa; Montanari, Paola; Feliciani, Claudio; Fabrizi, Giuseppe; Pagliarello, Calogero

2015-09-01

Photodynamic therapy with 5-methyl-aminolevulinate and photodynamic therapy with trichloroacetic acid 50% are the two techniques utilized in the management of actinic keratosis. This study was planned to compare the efficacy, adverse effects, recurrence and cosmetic outcome of these option therapies in patients with multiple actinic keratosis of the scalp. Thirteen patients with multiple actinic keratosis were treated with one of the two treatments on half of the scalp at baseline, while the other treatment was performed on the other half 15 days apart, randomly. Efficacy, adverse effects, cosmetic outcome and recurrence were recorded at follow-up visit at 1, 3, 6 and 12 months. Photodynamic therapy with 5 methyl-aminolevulinate was more effective than trichloroacetic acid although less tolerated by patients as it was more painful. Early adverse effects were almost the same even if trichloroacetic acid leads also to crust formation and to a worse cosmetic outcome characterized by hypopigmentation. Recurrence was lower in the area treated with photodynamic therapy. Trichloroacetic acid 50% is less effective than photodynamic therapy with 5 methyl-aminolevulinate in the treatment of multiple actinic keratosis of the scalp although better tolerated by patients. As this technique is less painful and less expensive than photodynamic therapy, we hypothesize and suggest that more sequential treatments could lead to better results. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In silico modelling of apoptosis induced by photodynamic therapy.

PubMed

López-Marín, N; Mulet, R

2018-01-07

Photodynamic therapy (PDT) is an emergent technique used for the treatment of several diseases. After PDT, cells die by necrosis, apoptosis or autophagy. Necrosis is produced immediately during photodynamic therapy by high concentration of reactive oxygen species, apoptosis and autophagy are triggered by mild or low doses of light and photosensitizer. In this work we model the cell response to low doses of PDT assuming a bi-dimensional matrix of interacting cells. For each cell of the matrix we simulate in detail, with the help of the Gillespie's algorithm, the two main chemical pathways leading to apoptosis. We unveil the role of both pathways in the cell death rate of the tumor, as well as the relevance of several molecules in the process. Our model suggests values of concentrations for several species of molecules to enhance the effectiveness of PDT. Copyright © 2017 Elsevier Ltd. All rights reserved.

Peptide-based pharmacomodulation of a cancer-targeted optical imaging and photodynamic therapy agent

PubMed Central

Stefflova, Klara; Li, Hui; Chen, Juan; Zheng, Gang

2008-01-01

We designed and synthesized a folate receptor-targeted, water soluble, and pharmacomodulated photodynamic therapy (PDT) agent that selectively detects and destroys the targeted cancer cells while sparing normal tissue. This was achieved by minimizing the normal organ uptake (e.g., liver and spleen) and by discriminating between tumors with different levels of folate receptor (FR) expression. This construct (Pyro-peptide-Folate, PPF) is comprised of three components: 1) Pyropheophorbide a (Pyro) as an imaging and therapeutic agent, 2) peptide sequence as a stable linker and modulator improving the delivery efficiency, and 3) Folate as a homing molecule targeting FR-expressing cancer cells. We observed an enhanced accumulation of PPF in KB cancer cells (FR+) compared to HT 1080 cancer cells (FR-), resulting in a more effective post-PDT killing of KB cells over HT 1080 or normal CHO cells. The accumulation of PPF in KB cells can be up to 70% inhibited by an excess of free folic acid. The effect of Folate on preferential accumulation of PPF in KB tumors (KB vs. HT 1080 tumors 2.5:1) was also confirmed in vivo. In contrast to that, no significant difference between the KB and HT 1080 tumor was observed in case of the untargeted probe (Pyro-peptide, PP), eliminating the potential influence of Pyro’s own nonspecific affinity to cancer cells. More importantly, we found that incorporating a short peptide sequence considerably improved the delivery efficiency of the probe – a process we attributed to a possible peptide-based pharmacomodulation – as was demonstrated by a 50-fold reduction in PPF accumulation in liver and spleen when compared to a peptide-lacking probe (Pyro-K-Folate, PKF). This approach could potentially be generalized to improve the delivery efficiency of other targeted molecular imaging and photodynamic therapy agents. PMID:17298029

Biomedical applications of nano-titania in theranostics and photodynamic therapy.

PubMed

Rehman, F U; Zhao, C; Jiang, H; Wang, X

2016-01-01

Titanium dioxide (TiO2) is one of the most abundantly used nanomaterials for human life. It is used in sunscreen, photovoltaic devices, biomedical applications and as a food additive and environmental scavenger. Nano-TiO2 in biomedical applications is well documented. It is used in endoprosthetic implants and early theranostics of neoplastic and non-neoplastic maladies as a photodynamic therapeutic agent and as vehicles in nano-drug delivery systems. Herein, we focus on the recent advancements and applications of nano-TiO2 in bio-nanotechnology, nanomedicine and photodynamic therapy (PDT).

Block copolymer nanoassemblies for photodynamic therapy and diagnosis.

PubMed

Dickerson, Matthew; Bae, Younsoo

2013-11-01

Light can be a powerful therapeutic and diagnostic tool. Light-sensitive molecules can be used to develop locally targeted cancer therapeutics. This approach is known as photodynamic therapy (PDT). Similarly, it is possible to diagnose diseases and track the course of treatment in vivo using ligh-sensitive molecules. This methodology is referred to as photodynamic diagnosis (PDD). Despite the potential, many PDT and PDD agents have imperfect physiochemical properties for their successful clinical application. Nanotechnology may solve these issues by improving the viability of PDT and PDD. This review summarizes the current state of PDT and PDD development, the integration of nanotechnology in the field, and the prospective future applications, demonstrating the potential of PDT and PDD for improved cancer treatment and diagnosis.

The application of antimicrobial photodynamic therapy (aPDT) in dentistry: a critical review

PubMed Central

Carrera, E T; Dias, H B; Corbi, S C T; Marcantonio, R A C; Bernardi, A C A; Bagnato, V S; Hamblin, M R; Rastelli, A N S

2017-01-01

In recent years there have been an increasing number of in vitro and in vivo studies that show positive results regarding antimicrobial photodynamic therapy (aPDT) used in dentistry. These include applications in periodontics, endodontics, and mucosal infections caused by bacteria present as biofilms. Antimicrobial photodynamic therapy is a therapy based on the combination of a non-toxic photosensitizer (PS) and appropriate wavelength visible light, which in the presence of oxygen is activated to produce reactive oxygen species (ROS). ROS induce a series of photochemical and biological events that cause irreversible damage leading to the death of microorganisms. Many light-absorbing dyes have been mentioned as potential PS for aPDT and different wavelengths have been tested. However, there is no consensus on a standard protocol yet. Thus, the goal of this review was to summarize the results of research on aPDT in dentistry using the PubMed database focusing on recent studies of the effectiveness aPDT in decreasing microorganisms and microbial biofilms, and also to describe aPDT effects, mechanisms of action and applications. PMID:29151775

The application of antimicrobial photodynamic therapy (aPDT) in dentistry: a critical review

NASA Astrophysics Data System (ADS)

Carrera, E. T.; Dias, H. B.; Corbi, S. C. T.; Marcantonio, R. A. C.; Bernardi, A. C. A.; Bagnato, V. S.; Hamblin, M. R.; Rastelli, A. N. S.

2016-12-01

In recent years there have been an increasing number of in vitro and in vivo studies that show positive results regarding antimicrobial photodynamic therapy (aPDT) used in dentistry. These include applications in periodontics, endodontics, and mucosal infections caused by bacteria present as biofilms. Antimicrobial photodynamic therapy is a therapy based on the combination of a non-toxic photosensitizer (PS) and appropriate wavelength visible light, which in the presence of oxygen is activated to produce reactive oxygen species (ROS). ROS induce a series of photochemical and biological events that cause irreversible damage leading to the death of microorganisms. Many light-absorbing dyes have been mentioned as potential PS for aPDT and different wavelengths have been tested. However, there is no consensus on a standard protocol yet. Thus, the goal of this review was to summarize the results of research on aPDT in dentistry using the PubMed database focusing on recent studies of the effectiveness aPDT in decreasing microorganisms and microbial biofilms, and also to describe aPDT effects, mechanisms of action and applications.

Chemiluminescent Nanomicelles for Imaging Hydrogen Peroxide and Self-Therapy in Photodynamic Therapy

PubMed Central

Chen, Rui; Zhang, Luzhong; Gao, Jian; Wu, Wei; Hu, Yong; Jiang, Xiqun

2011-01-01

Hydrogen peroxide is a signal molecule of the tumor, and its overproduction makes a higher concentration in tumor tissue compared to normal tissue. Based on the fact that peroxalates can make chemiluminescence with a high efficiency in the presence of hydrogen peroxide, we developed nanomicelles composed of peroxalate ester oligomers and fluorescent dyes, called peroxalate nanomicelles (POMs), which could image hydrogen peroxide with high sensitivity and stability. The potential application of the POMs in photodynamic therapy (PDT) for cancer was also investigated. It was found that the PDT-drug-loaded POMs were sensitive to hydrogen peroxide, and the PDT drug could be stimulated by the chemiluminescence from the reaction between POMs and hydrogen peroxide, which carried on a self-therapy of the tumor without the additional laser light resource. PMID:21765637

Mechanistics and photo-energetics of macrocycles and photodynamic therapy: An overview of aspects to consider for research.

PubMed

Horne, Tamarisk K; Cronjé, Marianne J

2017-02-01

Research within the field of photodynamic therapy has escalated over the past 20 years. The required conjunctional use of photosensitizers, particularly of the macrocycle structure, has lead to a vast repertoire of derivatives that branch classes and subclasses thereof. Each exhibits a differential range of physiochemical properties that influence their potential applications within the larger phototherapy field for use in either diagnostics, photodynamic therapy, both or none. Herein, we provide an overview of these properties as they relate to photodynamic therapy and to a lesser extent diagnostics. By summarizing the mechanistics of photodynamic therapy coupled to the photo-energetics displayed by macrocycle photosensitizers, we aimed to highlight the critical aspects any researcher should be aware of and consider when selecting and performing research for therapeutic application purposes. These include photosensitizer, photophysical and structural properties, synthesis design and subsequent attributes, main applications within research, common shortcomings exhibited and the current methods practiced to overcome them. © 2017 John Wiley & Sons A/S.

Multifunctional nanoplatform for enhanced photodynamic cancer therapy and magnetic resonance imaging.

PubMed

Hao, Yongwei; Zhang, Bingxiang; Zheng, Cuixia; Niu, Mengya; Guo, Haochen; Zhang, Hongling; Chang, Junbiao; Zhang, Zhenzhong; Wang, Lei; Zhang, Yun

2017-03-01

Co-delivery of photosensitizers and synergistic agents by one single nanoplatform is interesting for enhancing photodynamic therapy (PDT) of cancer. Here, a multifunctional nanoplatform for enhanced photodynamic therapy and magnetic resonance imaging of cancer was constructed. The poly (lactide-co-glycolide) (PLGA) nanoparticles (NPs) loaded with hematoporphyrin monomethyl ether (HMME) were coated with multifunctional manganese dioxide (MnO 2 ) shells, which were designed as PLGA/HMME@MnO 2 NPs. Once the NPs were effectively taken up by tumor cells, the intracellular H 2 O 2 was catalysed by the MnO 2 shells to generate O 2 . Meanwhile, the higher glutathione (GSH) promoted the degradation of MnO 2 into Mn 2+ ions with the ability of magnetic resonance (MR) imaging. After the degradation of outer layer, the release of photosensitizer was promoted. Under irradiation, the released HMME produced cytotoxic reactive oxygen species (ROS) to damage the tumor cells when the O 2 was generated in the hypoxic tumor site. Furthermore, the decreased GSH level further inhibited the consumption of the produced ROS, which greatly enhanced the PDT efficacy. Therefore, this study suggested that this multifunctional system has the potential for enhanced photodynamic therapy and magnetic resonance imaging. Copyright © 2016 Elsevier B.V. All rights reserved.

Revisiting photodynamic therapy dosimetry: reductionist & surrogate approaches to facilitate clinical success

NASA Astrophysics Data System (ADS)

Pogue, Brian W.; Elliott, Jonathan T.; Kanick, Stephen C.; Davis, Scott C.; Samkoe, Kimberley S.; Maytin, Edward V.; Pereira, Stephen P.; Hasan, Tayyaba

2016-04-01

Photodynamic therapy (PDT) can be a highly complex treatment, with many parameters influencing treatment efficacy. The extent to which dosimetry is used to monitor and standardize treatment delivery varies widely, ranging from measurement of a single surrogate marker to comprehensive approaches that aim to measure or estimate as many relevant parameters as possible. Today, most clinical PDT treatments are still administered with little more than application of a prescribed drug dose and timed light delivery, and thus the role of patient-specific dosimetry has not reached widespread clinical adoption. This disconnect is at least partly due to the inherent conflict between the need to measure and understand multiple parameters in vivo in order to optimize treatment, and the need for expedience in the clinic and in the regulatory and commercialization process. Thus, a methodical approach to selecting primary dosimetry metrics is required at each stage of translation of a treatment procedure, moving from complex measurements to understand PDT mechanisms in pre-clinical and early phase I trials, towards the identification and application of essential dose-limiting and/or surrogate measurements in phase II/III trials. If successful, identifying the essential and/or reliable surrogate dosimetry measurements should help facilitate increased adoption of clinical PDT. In this paper, examples of essential dosimetry points and surrogate dosimetry tools that may be implemented in phase II/III trials are discussed. For example, the treatment efficacy as limited by light penetration in interstitial PDT may be predicted by the amount of contrast uptake in CT, and so this could be utilized as a surrogate dosimetry measurement to prescribe light doses based upon pre-treatment contrast. Success of clinical ALA-based skin lesion treatment is predicted almost uniquely by the explicit or implicit measurements of photosensitizer and photobleaching, yet the individualization of treatment

Differential antioxidant defense and detoxification mechanisms in photodynamically stressed rice plants treated with the deregulators of porphyrin biosynthesis, 5-aminolevulinic acid and oxyfluorfen.

PubMed

Phung, Thu-Ha; Jung, Sunyo

2015-04-03

This study focuses on differential molecular mechanisms of antioxidant and detoxification systems in rice plants under two different types of photodynamic stress imposed by porphyrin deregulators, 5-aminolevulinic acid (ALA) and oxyfluorfen (OF). The ALA-treated plants with white necrosis exhibited a greater decrease in photochemical quantum efficiency, Fv/Fm, as well as a greater increase in activity of superoxide dismutase, compared to the OF-treated plants. By contrast, the brown necrosis in OF-treated plants resulted in not only more widely dispersed H2O2 production and greater increases in H2O2-decomposing enzymes, catalase and peroxidase, but also lower ascorbate redox state. In addition, ALA- and OF-treated plants markedly up-regulated transcript levels of genes involved in detoxification processes including transport and movement, cellular homeostasis, and xenobiotic conjugation, with prominent up-regulation of serine/threonine kinase and chaperone only in ALA-treated plants. Our results demonstrate that different photodynamic stress imposed by ALA and OF developed differential actions of antioxidant enzymes and detoxification. Particularly, detoxification system may play potential roles in plant protection against photodynamic stress imposed by porphyrin deregulators, thereby contributing to alleviation of photodynamic damage. Copyright © 2015 Elsevier Inc. All rights reserved.

Photodynamic therapy for occluded biliary metal stents

NASA Astrophysics Data System (ADS)

Roche, Joseph V. E.; Krasner, Neville; Sturgess, R.

1999-02-01

In this abstract we describe the use of photodynamic therapy (PDT) to recanalize occluded biliary metal stents. In patients with jaundice secondary to obstructed metal stents PDT was carried out 72 hours after the administration of m THPC. Red laser light at 652 nm was delivered endoscopically at an energy intensity of 50 J/cm. A week later endoscopic retrograde cholangiogram showed complete recanalization of the metal stent.

Potentiation of ALA-PDT antitumor activity in mice using topical DMXAA

NASA Astrophysics Data System (ADS)

Marrero, Allison; Sunar, Ulas; Sands, Theresa; Oseroff, Allan; Bellnier, David

2009-06-01

Photodynamic treatment of subcutaneously implanted Colon 26 tumors in BALB/c mice using the aminolevulinic acid (ALA)-induced photosensitizer protoporphyrin IX (PpIX) was shown to be enhanced by the addition of the vascular disrupting agent 5,6-Dimethylxanthenone-4-acetic-acid (DMXAA; Novartis ASA404). DMXAA increases vascular permeability and decreases blood flow in both murine and human tumors. Sufficiently high parenteral DMXAA doses can lead to tumor collapse and necrosis. We have previously reported marked enhancement of antitumor activity when PDT, using either Photofrin or HPPH, is combined with low-dose intraperitoneal DMXAA. We now describe the first attempt to combine topically-applied DMXAA with PDT. For this, DMXAA was applied two hours before PpIX-activating light delivery. PDT with ALA-PDT alone (ALA 20%; 80 J/cm2 delivered at 75 mW/cm2) caused a 39% decrease in tumor volume compared to unirradiated controls. Addition of topical DMXAA to ALA-PDT resulted in a 74% reduction in tumor volume. Diffuse correlation spectroscopy (DCS), a non-invasive blood flow imaging method, is being used to understand the mechanism of this effect and to aid in the proper design of the therapy. For instance, our most recent DCS data suggests that the 2-hour interval between the DMXAA and light applications may not be optimum. This preliminary study suggests a potential role for topical DMXAA in combination with PDT for dermatologic tumors.

Photodynamic Therapy in Treatment of Oral Lichen Planus

PubMed Central

Mostafa, Diana; Tarakji, Bassel

2015-01-01

Oral lichen planus (OLP) is a relatively common chronic immunologic mucocutaneous disorder. Although there are many presenting treatments, some of them proved its failure. Recently, the use of photodynamic therapy (PDT) has been expanding due to its numerous advantages, as it is safe, convenient, and non-invasive and has toxic effect towards selective tissues. This article provides comprehensive review on OLP, its etiology, clinical features and recent non-pharmacological treatments. We also describe the topical PDT and its mechanisms. Our purpose was to evaluate the efficacy of PDT in treatment of OLP through collecting the data of the related clinical studies. We searched in PubMed website for the clinical studies that were reported from 2000 to 2014 using specific keywords: “photodynamic therapy” and “treatment of oral lichen planus”. Inclusion criteria were English publications only were concerned. In the selected studies of photodynamic treatment, adult patients (more than 20 years) were conducted and the OLP lesions were clinically and histologically confirmed. Exclusion criteria were classical and pharmacological treatments of OLP were excluded and also the using of PDT on skin lesions of lichen planus. We established five clinical studies in this review where all of them reported improvement and effectiveness of PDT in treatment of OLP lesions. The main outcome of comparing the related clinical studies is that the photodynamic is considered as a safe, effective and promising treatment modality for OLP. PMID:25883701

Development of a red diode laser system for photodynamic therapy

NASA Astrophysics Data System (ADS)

Halkiotis, Konstantinos N.; Yova, Dido M.; Uzunoglou, Nikolaos K.; Papastergiou, Georgios; Matakias, Sotiris; Koukouvinos, Ilias

1998-07-01

The effectiveness of photodynamic treatment modality has been proven experimentally for a large variety of tumors, during the last years. This therapy utilizes the combined action of light and photosensitizing drug. Until now, a disadvantage of PDT has be the low tissue penetration of light, at the wavelengths of most commonly available lasers, for clinical studies. The red wavelength offers the advantage of increased penetration depth in tissue, in addition several new wavelength offers the advantage of increased penetration depth in tissue, in addition several new photosensitizers present absorption band at the region 630nm to 690nm. The development of high power red diode laser system for photodynamic therapy, has provided a cost effective alternative to existing lasers for use in PDT. This paper will describe the system design, development and performance of a diode laser system, connected with a fiber optic facility, to be used for PDT. The system was based on a high power semiconductor diode laser emitting at 655nm. The laser output power was approximately 60mW at the output of a 62.5/125/900 micron fiber optic probe. FUll technical details and optical performance characteristics of the system will be discussed in this paper.

Kinetics of tumor necrosis factor production by photodynamic-therapy-activated macrophages

NASA Astrophysics Data System (ADS)

Pass, Harvey I.; Evans, Steven; Perry, Roger; Matthews, Wilbert

1990-07-01

The ability of photodynamic therapy (PDT) to activate macrophages and produce cytokines, specifically tumor necrosis factor (TNF), is unknown. Three day thioglycolate elicited macrophages were incubated with 25 ug/mi Photofrin II (P11) for 2 hour, after which they were subjected to 630 nm light with fluences of 0-1800 J/m. The amount of TNF produced in the system as well as macrophage viability was measured 1, 3, 6, and 18 hours after POT. The level of TNF produced by the macrophages was significantly elevated over control levels 6 hours after POT and the absolute level of tumor necrosis factor production was influenced by the treatment energy and the resulting macrophage cytotoxicity. These data suggest that POT therapy induced cytotoxicity in vivo may be amplified by macrophage stimulation to secrete cytokines and these cytokines may also participate in other direct/indirect photodynamic therapy effects, i.e. immunosuppression, vascular effects.

Colloidal plasmonic gold nanoparticles and gold nanorings: shape-dependent generation of singlet oxygen and their performance in enhanced photodynamic cancer therapy.

PubMed

Yang, Yamin; Hu, Yue; Du, Henry; Ren, Lei; Wang, Hongjun

2018-01-01

In recognition of the potentials of gold nanoparticles (Au NPs) in enhanced photodynamic therapy (PDT) for cancer, it is desirable to further understand the shape-dependent surface plasmonic resonance (SPR) properties of various gold nanostructures and evaluate their performances in PDT. Monodispersed colloidal spherical solid Au NPs were synthesized by UV-assisted reduction using chloroauric acid and sodium citrate, and hollow gold nanorings (Au NRs) with similar outer diameter were synthesized based on sacrificial galvanic replacement method. The enhanced electromagnetic (EM) field distribution and their corresponding efficiency in enhancing singlet oxygen ( 1 O 2 ) generation of both gold nanostructures were investigated based on theoretical simulation and experimental measurements. Their shape-dependent SPR response and resulted cell destruction during cellular PDT in combination with 5-aminolevulinic acid (5-ALA) were further studied under different irradiation conditions. With comparable cellular uptake, more elevated formation of 1 O 2 in 5-ALA-enabled PDT was detected with the presence of Au NRs than that with Au NPs under broadband light irradiation in both cell-free and intracellular conditions. As a result of the unique morphological attributes, exhibiting plasmonic effect of Au NRs was still achievable in the near infrared (NIR) region, which led to an enhanced therapeutic efficacy of PDT under NIR light irradiation. Shape-dependent SPR response of colloidal Au NPs and Au NRs and their respective effects in promoting PDT efficiency were demonstrated in present study. Our innovative colloidal Au NRs with interior region accessible to surrounding photosensitizers would serve as efficient enhancers of PDT potentially for deep tumor treatment.

New photosensitizers for photodynamic therapy

PubMed Central

Abrahamse, Heidi; Hamblin, Michael R.

2016-01-01

Photodynamic therapy (PDT) was discovered more than 100 years ago, and has since become a well-studied therapy for cancer and various non-malignant diseases including infections. PDT uses photosensitizers (PSs, non-toxic dyes) that are activated by absorption of visible light to initially form the excited singlet state, followed by transition to the long-lived excited triplet state. This triplet state can undergo photochemical reactions in the presence of oxygen to form reactive oxygen species (including singlet oxygen) that can destroy cancer cells, pathogenic microbes and unwanted tissue. The dual-specificity of PDT relies on accumulation of the PS in diseased tissue and also on localized light delivery. Tetrapyrrole structures such as porphyrins, chlorins, bacteriochlorins and phthalocyanines with appropriate functionalization have been widely investigated in PDT, and several compounds have received clinical approval. Other molecular structures including the synthetic dyes classes as phenothiazinium, squaraine and BODIPY (boron-dipyrromethene), transition metal complexes, and natural products such as hypericin, riboflavin and curcumin have been investigated. Targeted PDT uses PSs conjugated to antibodies, peptides, proteins and other ligands with specific cellular receptors. Nanotechnology has made a significant contribution to PDT, giving rise to approaches such as nanoparticle delivery, fullerene-based PSs, titania photocatalysis, and the use of upconverting nanoparticles to increase light penetration into tissue. Future directions include photochemical internalization, genetically encoded protein PSs, theranostics, two-photon absorption PDT, and sonodynamic therapy using ultrasound. PMID:26862179

New photosensitizers for photodynamic therapy.

PubMed

Abrahamse, Heidi; Hamblin, Michael R

2016-02-15

Photodynamic therapy (PDT) was discovered more than 100 years ago, and has since become a well-studied therapy for cancer and various non-malignant diseases including infections. PDT uses photosensitizers (PSs, non-toxic dyes) that are activated by absorption of visible light to initially form the excited singlet state, followed by transition to the long-lived excited triplet state. This triplet state can undergo photochemical reactions in the presence of oxygen to form reactive oxygen species (including singlet oxygen) that can destroy cancer cells, pathogenic microbes and unwanted tissue. The dual-specificity of PDT relies on accumulation of the PS in diseased tissue and also on localized light delivery. Tetrapyrrole structures such as porphyrins, chlorins, bacteriochlorins and phthalocyanines with appropriate functionalization have been widely investigated in PDT, and several compounds have received clinical approval. Other molecular structures including the synthetic dyes classes as phenothiazinium, squaraine and BODIPY (boron-dipyrromethene), transition metal complexes, and natural products such as hypericin, riboflavin and curcumin have been investigated. Targeted PDT uses PSs conjugated to antibodies, peptides, proteins and other ligands with specific cellular receptors. Nanotechnology has made a significant contribution to PDT, giving rise to approaches such as nanoparticle delivery, fullerene-based PSs, titania photocatalysis, and the use of upconverting nanoparticles to increase light penetration into tissue. Future directions include photochemical internalization, genetically encoded protein PSs, theranostics, two-photon absorption PDT, and sonodynamic therapy using ultrasound. © 2016 Authors; published by Portland Press Limited.

Photodynamic Cancer Therapy—Recent Advances

NASA Astrophysics Data System (ADS)

Abrahamse, Heidi

2011-09-01

The basic principle of the photodynamic effect was discovered over a hundred years ago leading to the pioneering work on PDT in Europe. It was only during the 1980s, however, when "photoradiation therapy" was investigated as a possible treatment modality for cancer. Photodynamic therapy (PDT) is a photochemotherapeutic process which requires the use of a photosensitizer (PS) that, upon entry into a cancer cell is targeted by laser irradiation to initiate a series of events that contribute to cell death. PSs are light-sensitive dyes activated by a light source at a specific wavelength and can be classified as first or second generation PSs based on its origin and synthetic pathway. The principle of PS activation lies in a photochemical reaction resulting from excitation of the PS producing singlet oxygen which in turn reacts and damages cell organelles and biomolecules required for cell function and ultimately leading to cell destruction. Several first and second generation PSs have been studied in several different cancer types in the quest to optimize treatment. PSs including haematoporphyrin derivative (HpD), aminolevulinic acid (ALA), chlorins, bacteriochlorins, phthalocyanines, naphthalocyanines, pheophorbiedes and purpurins all require selective uptake and retention by cancer cells prior to activation by a light source and subsequent cell death induction. Photodynamic diagnosis (PDD) is based on the fluorescence effect exhibited by PSs upon irradiation and is often used concurrently with PDT to detect and locate tumours. Both laser and light emitting diodes (LED) have been used for PDT depending on the location of the tumour. Internal cancers more often require the use of laser light delivery using fibre optics as delivery system while external PDT often make use of LEDs. Normal cells have a lower uptake of the PS in comparison to tumour cells, however the acute cytotoxic effect of the compound on the recovery rate of normal cells is not known. Subcellular

Barrett's esophagus: photodynamic therapy for ablation of dysplasia, reduction of specialized mucosa and treatment of superficial esophageal cancer

NASA Astrophysics Data System (ADS)

Overholt, Bergein F.; Panjehpour, Masoud

1995-03-01

Fifteen patients with Barrett's esophagus and dysplasia were treated with photodynamic therapy. Four patients also had early, superficial esophageal cancers and 5 had esophageal polyps. Light was delivered via a standard diffuser or a centering esophageal balloon. Eight patients maintained on omeprazole and followed for 6 - 54 months are the subject of this report. Photodynamic therapy ablated dysplastic or malignant mucosa in patients with superficial cancer. Healing and partial replacement of Barrett's mucosa with normal squamous epithelium occurred in all patients and complete replacement with squamous epithelium was found in two. Side effects included photosensitivity and mild-moderate chest pain and dysphagia for 5 - 7 days. In three patients with extensive circumferential mucosal ablation in the proximal esophagus, healing was associated with esophageal strictures which were treated successfully by esophageal dilation. Strictures were not found in the distal esophagus. Photodynamic therapy combined with long-term acid inhibition provides effective endoscopic therapy of Barrett's mucosal dysplasia and superficial (Tis-T1) esophageal cancer. The windowed centering balloon improves delivery of photodynamic therapy to diffusely abnormal esophageal mucosa.

Conjugate of biotin with silicon(IV) phthalocyanine for tumor-targeting photodynamic therapy.

PubMed

Li, Ke; Qiu, Ling; Liu, Qingzhu; Lv, Gaochao; Zhao, Xueyu; Wang, Shanshan; Lin, Jianguo

2017-09-01

In order to improve the efficacy of photodynamic therapy (PDT), biotin was axially conjugated with silicon(IV) phthalocyanine (SiPc) skeleton to develop a new tumor-targeting photosensitizer SiPc-biotin. The target compound SiPc-biotin showed much higher binding affinity toward BR-positive (biotin receptor overexpressed) HeLa human cervical carcinoma cells than its precursor SiPc-pip. However, when the biotin receptors of HeLa cells were blocked by free biotin, >50% uptake of SiPc-biotin was suppressed, demonstrating that SiPc-biotin could selectively accumulate in BR-positive cancer cells via the BR-mediated internalization. The confocal fluorescence images further confirmed the target binding ability of SiPc-biotin. As a consequence of specificity of SiPc-biotin toward BR-positive HeLa cells, the photodynamic effect was also largely dependent on the BR expression level of HeLa cells. The photodynamic activities of SiPc-biotin against HeLa cells were dramatically reduced when the biotin receptors were blocked by the free biotin (IC 50 : 0.18μM vs. 0.46μM). It is concluded that SiPc-biotin can selectively damage BR-positive cancer cells under irradiation. Furthermore, the dark toxicity of SiPc-biotin toward human normal liver cell lines LO2 was much lower than that of its precursor SiPc-pip. The targeting photodynamic activity and low dark toxicity suggest that SiPc-biotin is a promising photosensitizer for tumor-targeting photodynamic therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Clinical application of photodynamic medicine technology using light-emitting fluorescence imaging based on a specialized luminous source.

PubMed

Namikawa, Tsutomu; Fujisawa, Kazune; Munekage, Eri; Iwabu, Jun; Uemura, Sunao; Tsujii, Shigehiro; Maeda, Hiromichi; Kitagawa, Hiroyuki; Fukuhara, Hideo; Inoue, Keiji; Sato, Takayuki; Kobayashi, Michiya; Hanazaki, Kazuhiro

2018-04-04

The natural amino acid 5-aminolevulinic acid (ALA) is a protoporphyrin IX (PpIX) precursor and a new-generation photosensitive substance that accumulates specifically in cancer cells. When indocyanine green (ICG) is irradiated with near-infrared (NIR) light, it shifts to a higher energy state and emits infrared light with a longer wavelength than the irradiated NIR light. Photodynamic diagnosis (PDD) using ALA and ICG-based NIR fluorescence imaging has emerged as a new diagnostic technique. Specifically, in laparoscopic examinations for serosa-invading advanced gastric cancer, peritoneal metastases could be detected by ALA-PDD, but not by conventional visible-light imaging. The HyperEye Medical System (HEMS) can visualize ICG fluorescence as color images simultaneously projected with visible light in real time. This ICG fluorescence method is widely applicable, including for intraoperative identification of sentinel lymph nodes, visualization of blood vessels in organ resection, and blood flow evaluation during surgery. Fluorescence navigation by ALA-PDD and NIR using ICG imaging provides good visualization and detection of the target lesions that is not possible with the naked eye. We propose that this technique should be used in fundamental research on the relationship among cellular dynamics, metabolic enzymes, and tumor tissues, and to evaluate clinical efficacy and safety in multicenter cooperative clinical trials.

Photodynamic therapy and knocking out of single tumor cells by multiphoton excitation processes

NASA Astrophysics Data System (ADS)

Riemann, Iris; Fischer, Peter; Koenig, Karsten

2004-09-01

Near infrared (NIR) ultrashort laser pulses of 780 nm have been used to induce intracellular photodynamic reactions by nonlinear excitation of porphyrin photosensitizers. Intracellular accumulation and photobleaching of the fluorescent photosensitizers protoporphyrin IX and Photofrin (PF) have been studied by non-resonant two-photon fluorescence excitation of PF and aminolevulinic acid (ALA)-labeled Chinese hamster ovary (CHO) cells. To testify the efficacy of both substrates to induce irreversible destructive effects, the cloning efficiency (CE) of cells exposed to femtosecond pulses of a multiphoton laser scanning microscope (40x/1.3) was determined. In the case of Photofrin accumulation, CEs of 50% and 0% were obtained after 17 laserscans (2 mW?, 16 s/ frame) and 50 scans, respectively. All cells exposed to 50 scans died within 48h after laser exposure. 100 scans were required to induce lethal effects in ALA labeled cells. Sensitizer-free control cells could be scanned 250 times (1.1 h) and more without impact on the reproduction behavior, morphology, and vitality. In addition to the slow phototoxic effect by photooxidation processes, another destructive but immediate effect based on optical breakdown was induced when employing high intense NIR femtosecond laser beams. This was used to optically knock out single tumor cells in living mice (solid Ehrlich-Carcinoma) in a depth of 10 to 100 μm.

Non-toxic approach for treatment of breast cancer and its cutaneous metastasis: Capecitabine (Xeloda) enhanced photodynamic therapy in a murine tumor model

NASA Astrophysics Data System (ADS)

Anand, Sanjay; Denisyuk, Anton; Bullock, Taylor; Govande, Mukul; Maytin, Edward V.

2018-02-01

Breast cancer (BCA) is the most frequently diagnosed cancer in women, with distant metastases to lung, liver, bone and skin occurring in approximately 40% of cases. Radiation therapy (RT) has been successfully employed for the treatment of BCA; however, multiple rounds of RT are associated with undesirable cutaneous side effects. This study explores PDT as a therapeutic alternative, to be given alone or in combination with RT and chemotherapy. Earlier, we had developed differentiation-enhanced combination photodynamic therapy (cPDT) using a neoadjuvant (5-fluorouracil; 5FU) prior to PDT. The neoadjuvant increases the levels of PpIX, leading to better efficacy following aminolevulinate (ALA)- based PDT. Here, to avoid the toxicity of systemic 5FU, we used a nontoxic 5FU precursor (Capecitabine; CPBN) in a new cPDT regimen. CBPN, a standard chemotherapeutic for BCA, is metabolized to 5FU specifically within tumor tissue. Murine (4T1) BCA cells were injected into breast fat pads of nude mice. CPBN was administered by oral gavage followed by intraperitoneal ALA and red light for PDT. CPBN pretreatment of 4T1 tumors led to increased tumor cell differentiation (3.5 fold), homogenous elevation of intratumoral PpIX levels (4.5 fold), and enhanced tumor cell death post-PDT (5 fold), relative to vehicle control. Using an in vivo imaging system (IVIS), a decline in tumor growth following CPBN-PDT was observed. Results showing the effect of CPBN-PDT on distant metastases of BCA to lung, lymph nodes and skin will be presented. In summary, CPBN-PDT, a novel combination approach, has a significant potential for translation into the clinic.

Surgical scar remodelling after photodynamic therapy using aminolaevulinic acid or its methylester: a retrospective, blinded study of patients with field cancerization.

PubMed

Sakamoto, F H; Izikson, L; Tannous, Z; Zurakowski, D; Anderson, R Rox

2012-02-01

Photodynamic therapy (PDT) is a nonsurgical alternative to conventional tumour excision for nonmelanoma skin cancers (NMSCs). We evaluated whether patients with field cancerization (multiple NMSCs) treated with aminolaevulinic acid (ALA) or its methylester (MAL) for that indication had PDT-induced changes in surgical scars in the treatment field. Six adult patients with multiple NMSCs and a total of 21 scars from previous excisions were studied in a retrospective blinded evaluation from clinical photographs of scar response to ALA/MAL-PDT. After a 3-h application of topical 20% ALA or 16·8% MAL under occlusion, each field was irradiated with 635-nm light-emitting diode light at the fluence of 200Jcm(-2) . Patients underwent one to three PDT sessions per field at ∼1month intervals, to fields that included scars on the back, thigh, arms and neck. Pre- and post-treatment digital photographs of scars were combined into 92 pairs that were independently and blindly evaluated by three board-certified dermatologists. This study was performed at our academic practice at the Massachusetts General Hospital. PDT produced a statistically significant improvement in scar appearance. The degree of improvement correlated with the number of treatment sessions (two or three treatments; P<0·05). Improvement after a single treatment was not statistically different from baseline ratings (P=0·99). Surgical scar remodelling and clinical improvement may be accomplished via ALA/MAL-PDT, but may require repeated treatment sessions. Larger, prospective studies are necessary to confirm the effectiveness of PDT for this indication. © 2011 The Authors. BJD © 2011 British Association of Dermatologists.

Monitoring blood flow and photobleaching during topical ALA PDT treatment

NASA Astrophysics Data System (ADS)

Sands, Theresa L.; Sunar, Ulas; Foster, Thomas H.; Oseroff, Allan R.

2009-02-01

Photodynamic therapy (PDT) using topical aminolevulinic acid (ALA) is currently used as a clinical treatment for nonmelanoma skin cancers. In order to optimize PDT treatment, vascular shutdown early in treatment must be identified and prevented. This is especially important for topical ALA PDT where vascular shutdown is only temporary and is not a primary method of cell death. Shutdown in vasculature would limit the delivery of oxygen which is necessary for effective PDT treatment. Diffuse correlation spectroscopy (DCS) was used to monitor relative blood flow changes in Balb/C mice undergoing PDT at fluence rates of 10mW/cm2 and 75mW/cm2 for colon-26 tumors implanted intradermally. DCS is a preferable method to monitor the blood flow during PDT of lesions due to its ability to be used noninvasively throughout treatment, returning data from differing depths of tissue. Photobleaching of the photosensitizer was also monitored during treatment as an indirect manner of monitoring singlet oxygen production. In this paper, we show the conditions that cause vascular shutdown in our tumor model and its effects on the photobleaching rate.

Light emitting fabric technologies for photodynamic therapy.

PubMed

Mordon, Serge; Cochrane, Cédric; Tylcz, Jean Baptiste; Betrouni, Nacim; Mortier, Laurent; Koncar, Vladan

2015-03-01

Photodynamic therapy (PDT) is considered to be a promising method for treating various types of cancer. A homogeneous and reproducible illumination during clinical PDT plays a determinant role in preventing under- or over-treatment. The development of flexible light sources would considerably improve the homogeneity of light delivery. The integration of optical fiber into flexible structures could offer an interesting alternative. This paper aims to describe different methods proposed to develop Side Emitting Optical Fibers (SEOF), and how these SEOF can be integrated in a flexible structure to improve light illumination of the skin during PDT. Four main techniques can be described: (i) light blanket integrating side-glowing optical fibers, (ii) light emitting panel composed of SEOF obtained by micro-perforations of the cladding, (iii) embroidery-based light emitting fabric, and (iv) woven-based light emitting fabric. Woven-based light emitting fabrics give the best performances: higher fluence rate, best homogeneity of light delivery, good flexibility. Copyright © 2014 Elsevier B.V. All rights reserved.

[Cost-effectiveness of photodynamic therapy in age-related macular degeneration].

PubMed

Muslera, E; Natal, C

2006-04-01

The aim of this study was to estimate the public health service cost of visual acuity improvement or maintenance with photodynamic therapy in patients with age-related macular degeneration (ARMD). This illness is the most frequent cause of blindness in elderly patients in western countries. A cost-effectiveness analysis was carried out to compare photodynamic therapy versus no treatment. The analysis point of view was that of the health service. The improvement or maintenance of visual acuity and contrast sensitivity were considered efficacy results. Direct costs were estimated by means of cost accountancy. Quality adjusted costs per visual acuity life year gained (QACVAG) were calculated through utility values from other studies. The cost per year of maintenance of visual acuity in a two-year period was 36,530 euro for women and 34,804 euro for men. If this cost was estimated for life expectancy in Asturias, it would be reduced to 4,298 euro for women and 5,354 euro for men. If costs of the QACVAG, in a two-year period, were considered, photodynamic therapy would cost 66,931 euro for women and 70,249 euro for men. This cost-effectiveness analysis allows decisions to be made about public financing. Some research in our country suggests that public health financing should be provided for interventions whose cost-effectiveness is less than 30,000 euro of CVAQA. The treatment evaluated here far exceeds this value. It is recommended that the use of more restrictive patient selection, incorporating diagnostic criteria and patient autonomy indicators, could improve the results of this intervention.

Using photodynamic therapy to estimate effectiveness of innovative combined diclofenac and tazaroten therapy of disseminated actinic keratosis.

PubMed

Osiecka, Beata J; Jurczyszyn, Kamil; Nockowski, Piotr; Lipinski, Artur; Sieja, Agnieszka; Ziółkowski, Piotr

2015-01-01

Early diagnosis and therapy of precancerous lesions and malignant tumors belong to the most challenging tasks in modern medicine. Photodynamic diagnosis can help diagnose both precancerous lesions and early carcinoma. Actinic keratosis (AK) is the most common precancerous lesion of the skin. The available data show a high effectiveness of diclofenac in treating multifocal AK. We report a case of a 52-year-old woman who complained of multiple disseminated AK lesions predominantly on the lower limbs and trunk with a significant exacerbation within the last 6 months. Due to the spreading of disease and a high number of AK foci, as well as technical problems with visiting the hospital (PDT Laboratory), photodynamic therapy was not applied. The patient was treated for 2 months with a combination of local administration of 3% diclofenac and 0.1% tazaroten and 3% diclofenac only as a half side (left-right) comparison. The effects of therapy were later clinically evaluated and verified by means of photodynamic diagnosis (PDD) directly after therapy and at a follow-up examination 3 months later. The evaluation of treatment was blinded. Treatment with diclofenac only on the right side of the body resulted in clearing of 55% of all treated lesions, which increased to 60% three months after finishing therapy. On the left side of the body, where combined therapy (diclofenac 2 times daily on uneven dates and diclofenac once a day + tazaroten once a day on even dates) was used, 77.5% pathologic lesions disappeared, but this did not increase at follow up. The treatment of multifocal, disseminated AK is a difficult task and also burdensome for the patient due to side effects like scarring or burning and itching which occur during most therapies. Combined therapy with diclofenac and tazaroten supported by PDD may improve the effects of routine treatment of AK.

Scope of photodynamic therapy in periodontics.

PubMed

Kumar, Vivek; Sinha, Jolly; Verma, Neelu; Nayan, Kamal; Saimbi, C S; Tripathi, Amitandra K

2015-01-01

Periodontal disease results from inflammation of the supporting structure of the teeth and in response to chronic infection caused by various periodontopathic bacteria. The mechanical removal of this biofilm and adjunctive use of antibacterial disinfectants and antibiotics have been the conventional methods of periodontal therapy. However, the removal of plaque and the reduction in the number of infectious organisms can be impaired in sites with difficult access. Photodynamic therapy (PDT) is a powerful laser-initiated photochemical reaction, involving the use of a photoactive dye (photosensitizer) activated by light of a specific wavelength in the presence of oxygen. Application of PDT in periodontics such as pocket debridement, gingivitis, and aggressive periodontitis continue to evolve into a mature clinical treatment modality and is considered as a promising novel approach for eradicating pathogenic bacteria in periodontitis.

Anti-tumor effects on the combination of photodynamic therapy with arsenic compound in TC-1 cells implanted C57BL/6 mice

NASA Astrophysics Data System (ADS)

Lee, Kyu Wan; Wen, Lan Ying; Bae, Su Mi; Park, Choong Hak; Jeon, Woo Kyu; Lee, Doo Yun; Ahn, Woong Shick

2009-06-01

The effects of As4O6 were studied as adjuvant on photodynamic therapy. As4O6 is considered to have anticancer activity via several biological actions such as free radical producing and inhibition of VEGF expression. In vitro experiments, cell proliferation and morphology were determined by MTT assay. Also, quantitative PCR array was performed to study the synergetic mechanism. Additionally, this study was supported by the finding that combination of photodynamic therapy and As4O6 shows an inhibition effect of tumor growth in C57BL/6 mice with TC-1 cells xenographs in vivo. Radachlorin and As4O6 significantly inhibited TC-1 cell proliferation in a dose-dependent manner (P < 0.05). Antiproliferative effect of combination treatment was significantly higher than those of TC-1 cells treated with either photodynamic therapy or As4O6 (62.4 and 52.5% decrease, respectively, compared to photodynamic therapy or As4O6 alone, P < 0.05). In addition, cell proliferation in combination of photodynamic therapy and As4O6 treatment significantly decreased by 77.4% compared to vehicle-only treated TC-1 cells (P < 0.05). Cell survival pathway (Naip1, Tert and Aip1) and p53-dependent pathway (Bax, p21Cip1, Fas, Gadd45, IGFBP-3 and Mdm-2) were markedly increased by combination treatment of photodynamic therapy and As4O6. Besides, the immunology response NEAT pathway (Ly- 12, CD178 and IL-2) also modulated after combination treatment of photodynamic therapy and As4O6. This combination effect apparently shows a same pattern in vivo model. These findings suggest the benefit of the combination treatment of photodynamic therapy and As4O6 for the inhibition of cervical cancer growth.

Photodynamic therapy for periodontal disease

NASA Astrophysics Data System (ADS)

Weersink, Robert A.

2002-05-01

Periodontal disease is a family of chronic inflammatory conditions caused by bacterial infections.' It is manifested in red, swollen gingiva (gums) and can lead to destruction of the connective tissue and bone that hold teeth in place. Conventional treatments typically require some form of invasive surgery, depending on the disease stage at time of detection. Photodynamic Therapy (PDT) is the use of light-activated drugs (photosensitizers) for treatment of a variety of conditions 2 such as solid tumors, pre-malignancies, macular degeneration and actinic keratitis. There have been a number of studies of PDT as an antibacterial agent. 3'4 Depending on the photosensitizer and strain of bacteria, significant killing (several LOGS) can be achieved.

Pyropheophorbide A and c(RGDyK) comodified chitosan-wrapped upconversion nanoparticle for targeted near-infrared photodynamic therapy.

PubMed

Zhou, Aiguo; Wei, Yanchun; Wu, Baoyan; Chen, Qun; Xing, Da

2012-06-04

Near-infrared (NIR)-to-visible upconversion nanoparticle (UCNP) has shown promising prospects in photodynamic therapy (PDT) as a drug carrier or energy donor. In this work, a photosensitizer pyropheophorbide a (Ppa) and RGD peptide c(RGDyK) comodified chitosan-wrapped NaYF(4):Yb/Er upconversion nanoparticle UCNP-Ppa-RGD was developed for targeted near-infrared photodynamic therapy. The properties of UCNP-Ppa-RGD, such as morphology, stability, optical spectroscopy and singlet oxygen generation efficiency, were investigated. The results show that covalently linked pyropheophorbide a molecule not only is stable but also retains its spectroscopic and functional properties. In vitro studies confirm a stronger targeting specificity of UCNP-Ppa-RGD to integrin α(v)β(3)-positive U87-MG cells compared with that in the corresponding negative group. The photosensitizer-attached nanostructure exhibited low dark toxicity and high phototoxicity against cancer cells upon 980 nm laser irradiation at an appropriate dosage. These results represent the first demonstration of a highly stable and efficient photosensitizer modified upconversion nanostructure for targeted near-infrared photodynamic therapy of cancer cells. The novel UCNP-Ppa-RGD nanoparticle may provide a powerful alternative for near-infrared photodynamic therapy with an improved tumor targeting specificity.

Laser-induced fluorescence diagnostics of basal cell carcinomas of the skin following topical ALA application

NASA Astrophysics Data System (ADS)

af Klinteberg, Claes; Nilsson, Annika M.; Wang-Nordman, Ingrid; Andersson-Engels, Stefan; Svanberg, Sune; Svanberg, Katarina

1996-12-01

Fourteen patients with superficial basal cell carcinomas (BCCs) and fifteen patients with nodular BCCs were investigated by means of laser-induced fluorescence (LIF) in connection with photodynamic therapy (PDT). Topical application of (delta) -amino levulinic acid (ALA) was performed six hours prior to the treatment session. Fluorescence spectra were recorded, using a point-monitoring system with an excitation wavelength of 405 nm. The measurements were performed in scans over the lesion and the surrounding normal skin before application of ALA, and immediately before and after the laser treatment. The selective uptake of the photosensitive resulted in a fluorescence intensity ratio of 2.4:1 for superficial BCCs and 2.5:1 for nodular BCCs. If the fluorescence intensity was divided by the autofluorescence, this resulted in a contrast enhancement of about a factor 6 for tumor tissue. In seven patients (five with nodular BCC and two with superficial BCC), additional fluorescence measurements were performed two and four hours following the ALA application, and two hours after the PDT procedure. Thus, the kinetics of the transformation of ALA to protoporphyrin IX (PpIX) could be followed, which indicated that the synthesis of PpIX was more rapid in the tumor than in the normal tissue. After four hours, the PpIX level inside the tumour was saturated, while there still was an accumulation in the surrounding skin. The highest contrast between tumor and normal skin was reached within two hours after the ALA application.

Surgery combined with local 5-aminolevulinic acid-photodynamic therapy on skin cancer and its effect on the expression of cyclophilin A, cyclophilin B and CD147

PubMed Central

Guo, Ling; Han, Yingsheng

2017-01-01

The study evaluated an approach to treat skin cancer using surgery combined with local 5-aminolevulinic acid-photodynamic therapy (ALA-PDT). Seventy-six patients with skin cancer who were admitted to the Liaocheng People's Hospital from May 2014 to April 2015 were randomly divided into a control and an observation group (38 cases in each). The patients in the control group were treated with ALA-PDT alone. Those in the observation group were first subjected to surgical treatment, and then treated with ALA-PDT. The treatment efficacies of the two groups were compared. The expression of cancer markers CyPA, CyPB and CD147 were detected by immunohistochemical methods before and after the treatment. Our results showed the average healing time of the wounds of patients in the observation group was shorter, the number of treatments needed was less, the efficacy rate and the lesion appearance satisfaction were significantly higher, and the recurrence rate at 12 months after treatment and the incidence of adverse reactions were both significantly lower. Additionally, the levels of CyPA, CyPB and CD147 were reduced to a significantly higher degree after treatment in the observation group. No difference was found in the recurrence rate between the two groups at 6 months after treatment. We conclude that surgery combined with ALA-PDT is a safe and reliable treatment method, which can increase the survival rate while improving the recovery rate and appearance satisfaction in patients with skin cancer. PMID:28789363

Surgery combined with local 5-aminolevulinic acid-photodynamic therapy on skin cancer and its effect on the expression of cyclophilin A, cyclophilin B and CD147.

PubMed

Guo, Ling; Han, Yingsheng

2017-08-01

The study evaluated an approach to treat skin cancer using surgery combined with local 5-aminolevulinic acid-photodynamic therapy (ALA-PDT). Seventy-six patients with skin cancer who were admitted to the Liaocheng People's Hospital from May 2014 to April 2015 were randomly divided into a control and an observation group (38 cases in each). The patients in the control group were treated with ALA-PDT alone. Those in the observation group were first subjected to surgical treatment, and then treated with ALA-PDT. The treatment efficacies of the two groups were compared. The expression of cancer markers CyPA, CyPB and CD147 were detected by immunohistochemical methods before and after the treatment. Our results showed the average healing time of the wounds of patients in the observation group was shorter, the number of treatments needed was less, the efficacy rate and the lesion appearance satisfaction were significantly higher, and the recurrence rate at 12 months after treatment and the incidence of adverse reactions were both significantly lower. Additionally, the levels of CyPA, CyPB and CD147 were reduced to a significantly higher degree after treatment in the observation group. No difference was found in the recurrence rate between the two groups at 6 months after treatment. We conclude that surgery combined with ALA-PDT is a safe and reliable treatment method, which can increase the survival rate while improving the recovery rate and appearance satisfaction in patients with skin cancer.

Photodynamic therapy to treat periimplantitis.

PubMed

Bombeccari, Gian Paolo; Guzzi, Gianpaolo; Gualini, Federico; Gualini, Sara; Santoro, Franco; Spadari, Francesco

2013-12-01

: Periimplantitis is a bacterial complication after dental implants implantation. Photodynamic therapy (PDT) implies the use of low-power laser in combination with appropriate photosensitizer to increase the detoxification of the implant surfaces. Little information exists about PDT in the treatment of periimplantitis. A randomized comparative case-control study has been conducted with 20 patients and 20 controls to compare the efficacy of antimicrobial PDT versus surgical therapy in patients with periimplantitis, who have received dental implants with rough surfaces. In the surgery group, mucoperiosteal flap surgery was used with scaling on implant surfaces and debridement of granulation tissue. Microbiologic testing was evaluated before and after intervention treatment, at 12 and 24 weeks in the study subjects. Total anaerobic counts of bacteria did not differ significantly between patients assigned to receive PDT and those assigned to receive surgical therapy (mean, 95.2% and 80.85%, respectively). PDT was associated with a significant decrease in bleeding scores (P = 0.02) as well as inflammatory exudation (P = 0.001). Treatment with PDT in patients with periimplantitis was not associated with major reduction of total anaerobic bacteria on the rough surfaces of dental implants as compared with surgical therapy. A significantly lower proinflammatory index of periimplantitis was observed in the PDT group at 24 weeks of follow-up.

In vitro study for photodynamic therapy using Fotolon in glioma treatment

NASA Astrophysics Data System (ADS)

Abdel Hamid, Sara; Zimmermann, Wolfgang; Huettenberger, Dirk; Wittig, Rainer; Abdel Kader, Mahmoud; Stepp, Herbert

2015-07-01

Several forms of Chlorin e6 and its derivatives are reported as efficient photosensitizers (PS) studied in Photodynamic Therapy (PDT) for oncologic applications. Fotolon® is a pure form of Chlorin e6 trisodium salt developed by Apocare Pharma.

Ecological photodynamic therapy: new trend to disrupt the intricate networks within tumor ecosystem.

PubMed

Rumie Vittar, N Belén; Lamberti, María Julia; Pansa, María Florencia; Vera, Renzo E; Rodriguez, M Exequiel; Cogno, I Sol; Milla Sanabria, Laura N; Rivarola, Viviana A

2013-01-01

As with natural ecosystems, species within the tumor microenvironment are connected by pairwise interactions (e.g. mutualism, predation) leading to a strong interdependence of different populations on each other. In this review we have identified the ecological roles played by each non-neoplastic population (macrophages, endothelial cells, fibroblasts) and other abiotic components (oxygen, extracellular matrix) directly involved with neoplastic development. A way to alter an ecosystem is to affect other species within the environment that are supporting the growth and survival of the species of interest, here the tumor cells; thus, some features of ecological systems could be exploited for cancer therapy. We propose a well-known antitumor therapy called photodynamic therapy (PDT) as a novel modulator of ecological interactions. We refer to this as "ecological photodynamic therapy." The main goal of this new strategy is the improvement of therapeutic efficiency through the disruption of ecological networks with the aim of destroying the tumor ecosystem. It is therefore necessary to identify those interactions from which tumor cells get benefit and those by which it is impaired, and then design multitargeted combined photodynamic regimes in order to orchestrate non-neoplastic populations against their neoplastic counterpart. Thus, conceiving the tumor as an ecological system opens avenues for novel approaches on treatment strategies. Copyright © 2012 Elsevier B.V. All rights reserved.

A graphene oxide based smart drug delivery system for tumor mitochondria-targeting photodynamic therapy

NASA Astrophysics Data System (ADS)

Wei, Yanchun; Zhou, Feifan; Zhang, Da; Chen, Qun; Xing, Da

2016-02-01

Subcellular organelles play critical roles in cell survival. In this work, a novel photodynamic therapy (PDT) drug delivery and phototoxicity on/off nano-system based on graphene oxide (NGO) as the carrier is developed to implement subcellular targeting and attacking. To construct the nanodrug (PPa-NGO-mAb), NGO is modified with the integrin αvβ3 monoclonal antibody (mAb) for tumor targeting. Pyropheophorbide-a (PPa) conjugated with polyethylene-glycol is used to cover the surface of the NGO to induce phototoxicity. Polyethylene-glycol phospholipid is loaded to enhance water solubility. The results show that the phototoxicity of PPa on NGO can be switched on and off in organic and aqueous environments, respectively. The PPa-NGO-mAb assembly is able to effectively target the αvβ3-positive tumor cells with surface ligand and receptor recognition; once endocytosized by the cells, they are observed escaping from lysosomes and subsequently transferring to the mitochondria. In the mitochondria, the `on' state PPa-NGO-mAb performs its effective phototoxicity to kill cells. The biological and physical dual selections and on/off control of PPa-NGO-mAb significantly enhance mitochondria-mediated apoptosis of PDT. This smart system offers a potential alternative to drug delivery systems for cancer therapy.Subcellular organelles play critical roles in cell survival. In this work, a novel photodynamic therapy (PDT) drug delivery and phototoxicity on/off nano-system based on graphene oxide (NGO) as the carrier is developed to implement subcellular targeting and attacking. To construct the nanodrug (PPa-NGO-mAb), NGO is modified with the integrin αvβ3 monoclonal antibody (mAb) for tumor targeting. Pyropheophorbide-a (PPa) conjugated with polyethylene-glycol is used to cover the surface of the NGO to induce phototoxicity. Polyethylene-glycol phospholipid is loaded to enhance water solubility. The results show that the phototoxicity of PPa on NGO can be switched on and off in

Antimicrobial Activity of Photodynamic Therapy Against Enterococcus faecalis Before and After Reciprocating Instrumentation in Permanent Molars.

PubMed

Pinheiro, Sérgio Luiz; Azenha, Giuliana Rodrigues; Democh, Yasmin Marialva; Nunes, Daniela Camila; Provasi, Silvia; Fontanetti, Giovana Masiero; Duarte, Danilo Antônio; Fontana, Carlos Eduardo; da Silveira Bueno, Carlos Eduardo

2016-12-01

The present study sought to evaluate the antimicrobial activity against Enterococcus faecalis of photodynamic therapy applied before and after reciprocating instrumentation of permanent molars. Apical extrusion of debris can cause flare-ups due to introduction of bacteria into the periapical tissues. Eighteen mesial roots from permanent mandibular molars were selected. The crowns were removed to obtain a standard root length of 15 mm. The included mesial roots had an angulation of 10°-40° and canals with independent foramina. The orifice of each mesiolingual canal was sealed with light-curing resin, and the working length was established visually, 1 mm short of the apical foramen. The roots were rendered impermeable and sterilized, and the mesiobuccal canals were contaminated with a standard strain of E. faecalis for 21 days. Specimens were randomly divided into three groups (n = 6): G1, photodynamic therapy performed before instrumentation and irrigation with 0.9% NaCl (saline) solution; G2, photodynamic therapy performed after instrumentation and irrigation with 0.9% NaCl; and G3 (control), instrumentation and irrigation with 2.5% NaOCl (sodium hypochlorite) solution. Canals were shaped with a WaveOne primary file (25.08) and irrigated with 0.9% NaCl. E. faecalis samples were collected before and after each procedure, and the results were analyzed using descriptive statistics and the Kruskal-Wallis and Wilcoxon tests. Significant reductions in E. faecalis were observed when photodynamic therapy was performed before and after instrumentation of the root canal system (p < 0.05). Reciprocating instrumentation significantly reduced E. faecalis colonies in experimentally contaminated root canal systems (p < 0.05). Photodynamic therapy was effective in removing E. faecalis from the root canal system, whether performed before or after reciprocating instrumentation.

Acceleration Of Wound Healing Ny Photodynamic Therapy

DOEpatents

Hasan, Tayyaba; Hamblin, Michael R.; Trauner, Kenneth

2000-08-22

Disclosed is a method for accelerating wound healing in a mammal. The method includes identifying an unhealed wound site or partially-healed wound site in a mammal; administering a photosensitizer to the mammal; waiting for a time period wherein the photosensitizer reaches an effective tissue concentration at the wound site; and photoactivating the photosensitizer at the wound site. The dose of photodynamic therapy is selected to stimulate the production of one or more growth factor by cells at the wound site, without causing tissue destruction.

Colloidal plasmonic gold nanoparticles and gold nanorings: shape-dependent generation of singlet oxygen and their performance in enhanced photodynamic cancer therapy

PubMed Central

Yang, Yamin; Hu, Yue; Du, Henry; Ren, Lei; Wang, Hongjun

2018-01-01

Introduction In recognition of the potentials of gold nanoparticles (Au NPs) in enhanced photodynamic therapy (PDT) for cancer, it is desirable to further understand the shape-dependent surface plasmonic resonance (SPR) properties of various gold nanostructures and evaluate their performances in PDT. Materials and methods Monodispersed colloidal spherical solid Au NPs were synthesized by UV-assisted reduction using chloroauric acid and sodium citrate, and hollow gold nanorings (Au NRs) with similar outer diameter were synthesized based on sacrificial galvanic replacement method. The enhanced electromagnetic (EM) field distribution and their corresponding efficiency in enhancing singlet oxygen (1O2) generation of both gold nanostructures were investigated based on theoretical simulation and experimental measurements. Their shape-dependent SPR response and resulted cell destruction during cellular PDT in combination with 5-aminolevulinic acid (5-ALA) were further studied under different irradiation conditions. Results With comparable cellular uptake, more elevated formation of 1O2 in 5-ALA-enabled PDT was detected with the presence of Au NRs than that with Au NPs under broadband light irradiation in both cell-free and intracellular conditions. As a result of the unique morphological attributes, exhibiting plasmonic effect of Au NRs was still achievable in the near infrared (NIR) region, which led to an enhanced therapeutic efficacy of PDT under NIR light irradiation. Conclusion Shape-dependent SPR response of colloidal Au NPs and Au NRs and their respective effects in promoting PDT efficiency were demonstrated in present study. Our innovative colloidal Au NRs with interior region accessible to surrounding photosensitizers would serve as efficient enhancers of PDT potentially for deep tumor treatment. PMID:29670350

Ultralow-Power Near Infrared Lamp Light Operable Targeted Organic Nanoparticle Photodynamic Therapy.

PubMed

Huang, Ling; Li, Zhanjun; Zhao, Yang; Zhang, Yuanwei; Wu, Shuang; Zhao, Jianzhang; Han, Gang

2016-11-09

Tissue penetration depth is a major challenge in practical photodynamic therapy (PDT). A biocompatible and highly effective near infrared (NIR)-light-absorbing carbazole-substituted BODIPY (Car-BDP) molecule is reported as a class of imaging-guidable deep-tissue activatable photosensitizers for PDT. Car-BDP possesses an intense, broad NIR absorption band (600-800 nm) with a remarkably high singlet oxygen quantum yield (Φ Δ = 67%). After being encapsulated with biodegradable PLA-PEG-FA polymers, Car-BDP can form uniform and small organic nanoparticles that are water-soluble and tumor-targetable. Rather than using laser light, such nanoparticles offer an unprecedented deep-tissue, tumor targeting photodynamic therapeutic effect by using an exceptionally low-power-density and cost-effective lamp light (12 mW cm -2 ). In addition, these nanoparticles can be simultaneously traced in vivo due to their excellent NIR fluorescence. This study signals a major step forward in photodynamic therapy by developing a new class of NIR-absorbing biocompatible organic nanoparticles for effective targeting and treatment of deep-tissue tumors. This work also provides a potential new platform for precise tumor-targeting theranostics and novel opportunities for future affordable clinical cancer treatment.

Nanoparticle-mediated combination chemotherapy and photodynamic therapy overcomes tumor drug resistance.

PubMed

Khdair, Ayman; Chen, Di; Patil, Yogesh; Ma, Linan; Dou, Q Ping; Shekhar, Malathy P V; Panyam, Jayanth

2010-01-25

Tumor drug resistance significantly limits the success of chemotherapy in the clinic. Tumor cells utilize multiple mechanisms to prevent the accumulation of anticancer drugs at their intracellular site of action. In this study, we investigated the anticancer efficacy of doxorubicin in combination with photodynamic therapy using methylene blue in a drug-resistant mouse tumor model. Surfactant-polymer hybrid nanoparticles formulated using an anionic surfactant, Aerosol-OT (AOT), and a naturally occurring polysaccharide polymer, sodium alginate, were used for synchronized delivery of the two drugs. Balb/c mice bearing syngeneic JC tumors (mammary adenocarcinoma) were used as a drug-resistant tumor model. Nanoparticle-mediated combination therapy significantly inhibited tumor growth and improved animal survival. Nanoparticle-mediated combination treatment resulted in enhanced tumor accumulation of both doxorubicin and methylene blue, significant inhibition of tumor cell proliferation, and increased induction of apoptosis. These data suggest that nanoparticle-mediated combination chemotherapy and photodynamic therapy using doxorubicin and methylene blue has significant therapeutic potential against drug-resistant tumors. Copyright 2009 Elsevier B.V. All rights reserved.

Methyl - aminolevulinic acid photodynamic therapy and topical tretinoin in a patient with vulvar extramammary Paget's disease.

PubMed

Magnano, Michela; Loi, Camilla; Bardazzi, Federico; Burtica, Elena Cleopatra; Patrizi, Annalisa

2013-01-01

Extramammary Paget's disease is a rare neoplasm of apocrine gland-bearing areas of the skin. The most common site of presentation is the vulva. Surgery is the most frequently reported therapy so far; however, it is invasive and it is complicated by a high rate of recurrence. For this reason, several less-invasive treatments have been recently proposed, including photodynamic therapy. We describe in this article the case of an 84-year-old patient with a noninvasive vulvar extramammary Paget's disease successfully treated with methyl-aminolevulinic acid photodynamic therapy associated with topical tretinoin. © 2013 Wiley Periodicals, Inc.

Combination of photodynamic and ultrasonic therapy for treatment of infected wounds in animal model

NASA Astrophysics Data System (ADS)

Menyaev, Yulian A.; Zharov, Vladimir P.

2006-02-01

One of the important problems of modern medicine is treatment of infected wounds. There are many diversified expedients of treatment, but none of them obey the modern physician completely. The aim of this study is to develop and test a new combined method of photodynamic ultrasonic therapy (PDUST) for treatment of infected wounds with focus on experimental trials. PDUST is based on a combination of two methods: photodynamic (PD) therapy (PDT) with photosensitizer and low frequency ultrasonic (US) therapy with antibiotic as tools for treatment of wounds and effectively killing bacteria. The main parameters are: US frequency - 26.5 kHz; US tip elongation - 40+/-20 μm wavelength of light emitting diodes (LED) array - 660+/-10 nm; light intensity on biotissue surface - 1-2 mW/cm2; photosensitizer - an aluminum disulfonated phtalocyanine dissolved in a physiological solution in concentration 10 mg/l. The experiments were carried out with 70 male chinchilla rabbits divided into 7 groups, thus the dynamics of wounds healing were studied in different modes of PDUST. The PD and US methods supplement each other and in conjunction provide additive and especially synergetic effects. The experimental data demonstrated advantages of new technology in comparison with conventional methods in cases of treatment of extended suppurative inflammatory and profound wounds. The more detailed study of PDUST method's mechanism, which is based on low intensity of LED light, PD therapy and US influence is required.

Self-Monitoring Artificial Red Cells with Sufficient Oxygen Supply for Enhanced Photodynamic Therapy

NASA Astrophysics Data System (ADS)

Luo, Zhenyu; Zheng, Mingbin; Zhao, Pengfei; Chen, Ze; Siu, Fungming; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Zheng, Cuifang; Ma, Yifan; Cai, Lintao

2016-03-01

Photodynamic therapy has been increasingly applied in clinical cancer treatments. However, native hypoxic tumoural microenvironment and lacking oxygen supply are the major barriers hindering photodynamic reactions. To solve this problem, we have developed biomimetic artificial red cells by loading complexes of oxygen-carrier (hemoglobin) and photosensitizer (indocyanine green) for boosted photodynamic strategy. Such nanosystem provides a coupling structure with stable self-oxygen supply and acting as an ideal fluorescent/photoacoustic imaging probe, dynamically monitoring the nanoparticle biodistribution and the treatment of PDT. Upon exposure to near-infrared laser, the remote-triggered photosensitizer generates massive cytotoxic reactive oxygen species (ROS) with sufficient oxygen supply. Importantly, hemoglobin is simultaneously oxidized into the more active and resident ferryl-hemoglobin leading to persistent cytotoxicity. ROS and ferryl-hemoglobin synergistically trigger the oxidative damage of xenograft tumour resulting in complete suppression. The artificial red cells with self-monitoring and boosted photodynamic efficacy could serve as a versatile theranostic platform.

Intraperitoneal photodynamic therapy of the rat CC531 adenocarcinoma.

PubMed Central

Veenhuizen, R. B.; Marijnissen, J. P.; Kenemans, P.; Ruevekamp-Helmers, M. C.; 't Mannetje, L. W.; Helmerhorst, T. J.; Stewart, F. A.

1996-01-01

The goal of this study was to investigate the efficacy of photodynamic therapy (PDT) of a single tumour growing intraperitoneally. For this purpose the CC531 colon carcinoma, implanted in an intraperitoneal fat pad of Wag/RijA rats, was treated with intraperitoneal photodynamic therapy (IPPDT) using Photofrin as the photosensitiser. Two illumination techniques have been compared. An invasive illumination technique using Perspex blocks to illuminate 30 cm2 of the lower abdomen gave a significant delay in tumour growth with 25 J cm-2 applied 1 day after Photofrin. A minimally invasive illumination technique using a balloon catheter to illuminate 14 cm2 resulted in an equivalent growth delay with 75 J cm-2. The route of administration of the photosensitiser did not influence regrowth times of the tumour. Mitomycin C (MMC), a bioreductive agent, was used to exploit the known PDT-induced hypoxia. The combination of IPPDT with MMC resulted in an increased tumoricidal effect. In conclusion, IPPDT led to a significant growth delay for a single tumour implanted intraperitoneally and repetition of the PDT treatment was possible using a minimally invasive illumination technique. Repeated treatments resulted in increased tumour response. PMID:8645584

Monitoring photodynamic therapy with photoacoustic microscopy

NASA Astrophysics Data System (ADS)

Shao, Peng; Chapman, David W.; Moore, Ronald B.; Zemp, Roger J.

2015-10-01

We present our work on examining the feasibility of monitoring photodynamic therapy (PDT)-induced vasculature change with acoustic-resolution photoacoustic microscopy (PAM). Verteporfin, an FDA-approved photosensitizer for clinical PDT, was utilized. With a 60-μm-resolution PAM system, we demonstrated the capability of PAM to monitor PDT-induced vasculature variations in a chick chorioallantoic membrane model with topical application and in a rat ear with intravenous injection of the photosensitizer. We also showed oxygen saturation change in target blood vessels due to PDT. Success of the present approach may potentially lead to the application of PAM imaging in evaluating PDT efficacy, guiding treatment, and predicting responders from nonresponders.

SU-E-T-191: First Principle Calculation of Quantum Yield in Photodynamic Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abolfath, R; Guo, F; Chen, Z

Purpose: We present a first-principle method to calculate the spin transfer efficiency in oxygen induced by any photon fields especially in MeV energy range. The optical pumping is mediated through photosensitizers, e.g., porphyrin and/or ensemble of quantum dots. Methods: Under normal conditions, oxygen molecules are in the relatively non-reactive triplet state. In the presence of certain photosensitizer compounds such as porphyrins, electromagnetic radiation of specific wavelengths can excite oxygen to highly reactive singlet state. With selective uptake of photosensitizers by certain malignant cells, photon irradiation of phosensitized tumors can lead to selective killing of cancer cells. This is the basismore » of photodynamic therapy (PDT). Despite several attempts, PDT has not been clinically successful except in limited superficial cancers. Many parameters such as photon energy, conjugation with quantum dots etc. can be potentially combined with PDT in order to extend the role of PDT in cancer management. The key quantity for this optimization is the spin transfer efficiency in oxygen by any photon field. The first principle calculation model presented here, is an attempt to fill this need. We employ stochastic density matrix description of the quantum jumps and the rate equation methods in quantum optics based on Markov/Poisson processes and calculate time evolution of the population of the optically pumped singlet oxygen. Results: The results demonstrate the feasibility of our model in showing the dependence of the optical yield in generating spin-singlet oxygen on the experimental conditions. The adjustable variables can be tuned to maximize the population of the singlet oxygen hence the efficacy of the photodynamic therapy. Conclusion: The present model can be employed to fit and analyze the experimental data and possibly to assist researchers in optimizing the experimental conditions in photodynamic therapy.« less

A multicenter, randomized, vehicle-controlled phase 2 study of blue light photodynamic therapy with aminolevulinic acid HCl 20% topical solution for the treatment of actinic keratoses on the upper extremities: the effect of occlusion during the drug incubation period.

PubMed

Schmieder, George J; Huang, Eugene Y; Jarratt, Michael

2012-12-01

Photodynamic therapy (PDT) with aminolevulinic acid (ALA) has been shown to be safe and effective in the treatment of actinic keratoses (AKs) of the face and scalp. A recent small study has suggested that ALA-PDT can be effective for AKs of the dorsal hands/forearms. However, studies designed to provide sufficient statistical power to test this hypothesis are lacking in the literature. To determine and compare the safety and efficacy of blue light ALA-PDT vs blue light placebo vehicle (VEH) in the treatment of AKs of the upper extremities and to evaluate the effect of occlusion after application of ALA vs VEH. ALA or VEH was applied to both dorsal hands/forearms for the 3-hour incubation period before blue light treatment (10 J/ cm2). One extremity of each subject was covered with occlusive dressing during the incubation period. Treatment was repeated at week 8 if any AK lesions remained. The median AK lesion clearance rate at week 12 was 88.7% for extremities treated with occluded ALA (ALA+OCC), 70.0% for extremities treated with nonoccluded ALA, 16.7% for extremities treated with occluded VEH (VEH+OCC), and 5.6% for extremities treated with nonoccluded VEH (P<.0001). ALA+OCC resulted in a significantly higher clearance rate compared with the nonoccluded extremity at weeks 8 (P=.0006) and 12 (P=.0029). Thirty-four percent (12/35) of extremities treated with ALA+OCC had complete clearance of lesions at week 12 compared with 0% (0/35) of extremities treated with VEH+OCC (P=.0002). The safety pro!le in this study is consistent with previously reported side effects of the therapy. Blue light ALA-PDT following a 3-hour incubation appears efficacious for AK clearance of the upper extremities. Incubation using an occlusive dressing significantly increases the efficacy of the procedure and also increases the incidence and severity of some acute inflammatory side effects of PDT.

ALA-PpIX variability quantitatively imaged in A431 epidermoid tumors using in vivo ultrasound fluorescence tomography and ex vivo assay

NASA Astrophysics Data System (ADS)

DSouza, Alisha V.; Flynn, Brendan P.; Gunn, Jason R.; Samkoe, Kimberley S.; Anand, Sanjay; Maytin, Edward V.; Hasan, Tayyaba; Pogue, Brian W.

2014-03-01

Treatment monitoring of Aminolevunilic-acid (ALA) - Photodynamic Therapy (PDT) of basal-cell carcinoma (BCC) calls for superficial and subsurface imaging techniques. While superficial imagers exist for this purpose, their ability to assess PpIX levels in thick lesions is poor; additionally few treatment centers have the capability to measure ALA-induced PpIX production. An area of active research is to improve treatments to deeper and nodular BCCs, because treatment is least effective in these. The goal of this work was to understand the logistics and technical capabilities to quantify PpIX at depths over 1mm, using a novel hybrid ultrasound-guided, fiber-based fluorescence molecular spectroscopictomography system. This system utilizes a 633nm excitation laser and detection using filtered spectrometers. Source and detection fibers are collinear so that their imaging plane matches that of ultrasound transducer. Validation with phantoms and tumor-simulating fluorescent inclusions in mice showed sensitivity to fluorophore concentrations as low as 0.025μg/ml at 4mm depth from surface, as presented in previous years. Image-guided quantification of ALA-induced PpIX production was completed in subcutaneous xenograft epidermoid cancer tumor model A431 in nude mice. A total of 32 animals were imaged in-vivo, using several time points, including pre-ALA, 4-hours post-ALA, and 24-hours post-ALA administration. On average, PpIX production in tumors increased by over 10-fold, 4-hours post-ALA. Statistical analysis of PpIX fluorescence showed significant difference among all groups; p<0.05. Results were validated by exvivo imaging of resected tumors. Details of imaging, analysis and results will be presented to illustrate variability and the potential for imaging these values at depth.

Systemic photodynamic therapy in folliculitis decalvans.

PubMed

Collier, N J; Allan, D; Diaz Pesantes, F; Sheridan, L; Allan, E

2018-01-01

Folliculitis decalvans (FD) is classified as a primary neutrophilic cicatricial alopecia, and is estimated to account for approximately 10% of all cases of primary cicatricial alopecia. The role of dysfunctional immune activity and the presence of bacteria, particularly Staphylococcus aureus, appear pivotal. We describe a 26-year-old man with a 4-year history of FD that was recalcitrant to numerous systemic and topical therapies, whose disease was virtually cleared during a follow-up of 25 months following a course of treatment with systemic photodynamic therapy (PDT) using ultraviolet light (100-140 J/cm 2 ) with porfimer sodium 1 mg/kg as monotherapy. This is the first report of the use of systemic PDT as a treatment for FD. Systemic PDT has potent antibacterial effects with little or no resistance. In addition, systemic PDT provides local immunomodulation and improved scar healing. Significant adverse effects following systemic PDT with appropriate aftercare are rare. This case demonstrates that systemic PDT is a useful therapy option in the treatment of recalcitrant FD. © 2017 British Association of Dermatologists.

Apoptotic induction by photodynamic therapy using hexaminolevulinate with a literature review

NASA Astrophysics Data System (ADS)

Furre, Ingegerd E.; Nesland, Jahn M.; Peng, Qian

2009-06-01

Since the first report by Agarwal et al in 1991 on apoptotic induction by photodynamic therapy (PDT) with chloroaluminium phthalocyanine a large number of papers have come out to show that PDT can induce cell death through apoptosis. This finding may provide potential clinical impact on, for example, those tumor cells resistant to any cancer therapy. The present paper briefly reviews apoptosis with emphasis on PDT-induced apoptosis with hexaminolevulinate.

Biocompatible 5-Aminolevulinic Acid/Au Nanoparticle-Loaded Ethosomal Vesicles for In Vitro Transdermal Synergistic Photodynamic/Photothermal Therapy of Hypertrophic Scars

NASA Astrophysics Data System (ADS)

Zhang, Zheng; Chen, Yunsheng; Ding, Jiayue; Zhang, Chunlei; Zhang, Amin; He, Dannong; Zhang, Yixin

2017-12-01

Biocompatible 5-aminolevulinic acid/Au nanoparticle-loaded ethosomal vesicle (A/A-ES) is prepared via ultrasonication for synergistic transdermal photodynamic/photothermal therapy (PDT/PTT) of hypertrophic scar (HS). Utilizing ultrasonication, Au nanoparticles (AuNPs) are synthesized and simultaneously loaded in ethosomal vesicles (ES) without any toxic agents, and 5-aminolevulinic acid (ALA) is also loaded in ES with 20% of the entrapment efficiency (EE). The prepared A/A-ES displays strong absorbance in 600-650 nm due to the plasmonic coupling effect between neighboring AuNPs in the same A/A-ES, which can simultaneously stimulate A/A-ES to produce heat and enhance quantum yields of reactive oxygen species (ROS) by using 632 nm laser. In vitro transdermal penetrability study demonstrates that A/A-ES acts as a highly efficient drug carrier to enhance both ALA and AuNPs penetration into HS tissue . Taking human hypertrophic scar fibroblasts (HSF) as therapeutic targets, synergistic PDT/PTT of HS indicates that A/A-ES could enhance quantum yields of ROS by photothermal effect and localized surface plasmon resonance (LSPR) of AuNPs, resulting in a high level of apoptosis or necrosis. In a word, the prepared A/A-ES shows a better synergistic PDT/PTT efficiency for HSF than the individual PDT and PTT, encouraging perspective for treatment of HS.

Polymeric Nanoparticle-Based Photodynamic Therapy for Chronic Periodontitis in Vivo.

PubMed

de Freitas, Laura Marise; Calixto, Giovana Maria Fioramonti; Chorilli, Marlus; Giusti, Juçaíra Stella M; Bagnato, Vanderlei Salvador; Soukos, Nikolaos S; Amiji, Mansoor M; Fontana, Carla Raquel

2016-05-20

Antimicrobial photodynamic therapy (aPDT) is increasingly being explored for treatment of periodontitis. Here, we investigated the effect of aPDT on human dental plaque bacteria in suspensions and biofilms in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles (MB-NP) and red light at 660 nm. The effect of MB-NP-based aPDT was also evaluated in a clinical pilot study with 10 adult human subjects with chronic periodontitis. Dental plaque samples from human subjects were exposed to aPDT-in planktonic and biofilm phases-with MB or MB-NP (25 µg/mL) at 20 J/cm² in vitro. Patients were treated either with ultrasonic scaling and scaling and root planing (US + SRP) or ultrasonic scaling + SRP + aPDT with MB-NP (25 µg/mL and 20 J/cm²) in a split-mouth design. In biofilms, MB-NP eliminated approximately 25% more bacteria than free MB. The clinical study demonstrated the safety of aPDT. Both groups showed similar improvements of clinical parameters one month following treatments. However, at three months ultrasonic SRP + aPDT showed a greater effect (28.82%) on gingival bleeding index (GBI) compared to ultrasonic SRP. The utilization of PLGA nanoparticles encapsulated with MB may be a promising adjunct in antimicrobial periodontal treatment.

Tetraphenylporphyrin derivatives possessing piperidine group as potential agents for photodynamic therapy.

PubMed

Liao, Ping-Yong; Gao, Ying-Hua; Wang, Xin-Rong; Bao, Lei-Lei; Bian, Jun; Hu, Tai-Shan; Zheng, Mei-Zhen; Yan, Yi-Jia; Chen, Zhi-Long

2016-12-01

Photodynamic therapy (PDT) is a noninvasive therapeutic and promising procedure in cancer treatment and has attracted considerable attention in recent years. In the present paper, 2-piperidinetetraphenylporphyrin derivatives (P1-P3) conjugated with different substituents (Cl, Me, MeO group) at phenyl position were synthesized via nucleophilic substitution of 2-nitroporphyrin copper derivatives with piperidine by refluxing under a nitrogen atmosphere and then demetalization. The combination of 1 H NMR, 13 C NMR and HR-MS was used to elucidate the identities of them. Their photophysical and photochemical properties, intracellular localization, cytotoxicity in vitro and in vivo against QBC-939 cells were investigated. They have absorption at wavelength about 650nm. All synthesized photosensitizers showed low dark cytotoxicity and comparable with that of hematoporphyrin monomethyl ether (HMME). And they were more phototoxic than HMME to QBC-939 cells in vitro. In bearing QBC-939 tumor BALB/c nude mice, when it treated with 5mg/kg dose of PS and laser light (650nm, 100J/cm 2 , 180mW/cm 2 ), the growth of tumor was inhibited compared to the control group. Among them, P3 exhibited better photodynamic antitumor efficacy on BALB/c nude mice at lower concentration. These results indicate that P3 is a new potential antitumor photosensitizer in photodynamic therapy and deserves further investigation. Copyright © 2016 Elsevier B.V. All rights reserved.

Photodynamic therapy: a promising alternative in oncology

NASA Astrophysics Data System (ADS)

Nelius, Thomas; de Riese, Werner T. W.; Filleur, Stephanie

2004-07-01

Photodynamic Therapy (PDT) is a treatment modality that is based on the administration of a photosensitizer and the following application of light in a wavelength range matching the absorption spectrum of the photosensitizer. Ideally the photosensitizer retains in the tumor tissue more than in normal tissue and thus allows targeted destruction of cancerous tissue. The use of PDT is slowly being accepted as a standard treatment for certain types of cancer. This includes mainly treatment strategies with only palliative intentions (obstructive esophageal cancer and advanced lung cancer) while for certain malignant conditions new applications exists that are already intended for cure (e.g. early stage of lung cancer). The main advantage of PDT is that the treatment can be repeated multiple times safely without major side effects. PDT can be safely combined with already established treatment options like surgery, chemotherapy or radiotherapy. A disadvantage of PDT is the only localized effect of the therapy, which usually cannot significantly alter the outcome of a systemic disease. In this paper we review the history of PDT as well as current clinical applications in oncology and future directions.

Using Fourier transform infrared spectroscopy to evaluate biological effects induced by photodynamic therapy.

PubMed

Lima, Cassio A; Goulart, Viviane P; Correa, Luciana; Zezell, Denise M

2016-07-01

Vibrational spectroscopic methods associated with multivariate statistical techniques have been succeeded in discriminating skin lesions from normal tissues. However, there is no study exploring the potential of these techniques to assess the alterations promoted by photodynamic effect in tissue. The present study aims to demonstrate the ability of Fourier Transform Infrared (FTIR) spectroscopy on Attenuated total reflection (ATR) sampling mode associated with principal component-linear discriminant analysis (PC-LDA) to evaluate the biochemical changes caused by photodynamic therapy (PDT) in skin neoplastic tissue. Cutaneous neoplastic lesions, precursors of squamous cell carcinoma (SCC), were chemically induced in Swiss mice and submitted to a single session of 5-aminolevulinic acid (ALA)-mediated PDT. Tissue sections with 5 μm thickness were obtained from formalin-fixed paraffin-embedded (FFPE) and processed prior to the histopathological analysis and spectroscopic measurements. Spectra were collected in mid-infrared region using a FTIR spectrometer on ATR sampling mode. Principal Component-Linear Discriminant Analysis (PC-LDA) was applied on preprocessed second derivatives spectra. Biochemical changes were assessed using PCA-loadings and accuracy of classification was obtained from PC-LDA . Sub-bands of Amide I (1,624 and 1,650 cm(-1) ) and Amide II (1,517 cm(-1) ) indicated a protein overexpression in non-treated and post-PDT neoplastic tissue compared with healthy skin, as well as a decrease in collagen fibers (1,204, 1,236, 1,282, and 1,338 cm(-1) ) and glycogen (1,028, 1,082, and 1,151 cm(-1) ) content. Photosensitized neoplastic tissue revealed shifted peak position and decreased β-sheet secondary structure of proteins (1,624 cm(-1) ) amount in comparison to non-treated neoplastic lesions. PC-LDA score plots discriminated non-treated neoplastic skin spectra from post-PDT cutaneous lesions with accuracy of 92.8%, whereas non-treated neoplastic

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy.

PubMed

de Annunzio, Sarah Raquel; de Freitas, Laura Marise; Blanco, Ana Lígia; da Costa, Mardoqueu Martins; Carmona-Vargas, Christian C; de Oliveira, Kleber Thiago; Fontana, Carla Raquel

2018-01-01

Bacterial resistance to available antibiotics nowadays is a global threat leading researchers around the world to study new treatment modalities for infections. Antimicrobial photodynamic therapy (aPDT) has been considered an effective and promising therapeutic alternative in this scenario. Briefly, this therapy is based on the activation of a non-toxic photosensitizing agent, known as photosensitizer (PS), by light at a specific wavelength generating cytotoxic singlet oxygen and free radicals. Virtually all studies related to aPDT involve a huge screening to identify ideal PS concentration and light dose combinations, a laborious and time-consuming process that is hardly disclosed in the literature. Herein, we describe an antimicrobial Photodynamic Therapy (aPDT) study against Enterococcus faecalis and Propionibacterium acnes employing methylene blue, chlorin-e6 or curcumin as PS. Similarities and discrepancies between the two bacterial species were pointed out in an attempt to speed up and facilitate futures studies against those clinical relevant strains. Susceptibility tests were performed by the broth microdilution method. Our results demonstrate that aPDT mediated by the three above-mentioned PS was effective in eliminating both gram-positive bacteria, although P. acnes showed remarkably higher susceptibility to aPDT when compared to E. faecalis. PS uptake assays revealed that P. acnes is 80 times more efficient than E. faecalis in internalizing all three PS molecules. Our results evidence that the cell wall structure is not a limiting feature when predicting bacterial susceptibility to aPDT treatment. Copyright © 2017. Published by Elsevier B.V.

Comparative study between the effects of photodynamic therapy and conventional therapy on microbial reduction in ligature-induced peri-implantitis in dogs.

PubMed

Hayek, Ricardo R A; Araújo, Ney S; Gioso, Marco A; Ferreira, Jonathan; Baptista-Sobrinho, Carlos A; Yamada, Aécio M; Ribeiro, Martha S

2005-08-01

Progressive peri-implant bone losses, which are accompanied by inflammatory lesions in the soft tissues, are referred to as peri-implantitis. The aim of this study was to compare the effects of photodynamic therapy (PDT) and conventional technique on microbial reduction in ligature-induced peri-implantitis in dogs. Eighteen third premolars from nine Labrador retriever dogs were extracted and the implants were submerged. After osseointegration, peri-implantitis was induced. After 4 months, ligature was removed and natural bacterial plaque was allowed to form for another 4 months. The animals were then randomly divided into two groups. In the conventional group, they were treated using mucoperiosteal flaps for scaling the implant surface and chlorexidine (conventional) irrigation. In the PDT group, only mucoperiosteal scaling was carried out before photodynamic therapy. Inside the peri-implant pocket, a paste-based azulene photosensitizer was placed and then a GaAlAs low-power laser (lambda=660 nm, P=40 mW, E=7.2 J for 3 minutes) was used. Microbiological samples were obtained before and immediately after treatment. Before treatment, one implant was removed and analyzed by scanning electron microscopy to validate the contamination. The results of this study showed that Prevotella sp., Fusobacterium sp., and S. Beta-haemolyticus were significantly reduced for both groups. After treatment, no significant differences were observed between the groups. These findings suggest that photodynamic therapy is a non-invasive method that could be used to reduce microorganisms in peri-implantitis. J Periodontol 2005;76:1275-1281.

Synthesis, bioanalysis and biodistribution of photosensitizer conjugates for photodynamic therapy

PubMed Central

Denis, Tyler GSt; Hamblin, Michael R

2013-01-01

Photodynamic therapy (PDT) was discovered in 1900 by Raab, and has since emerged as a promising tool for treating diseases characterized by unwanted cells or hyperproliferating tissue (e.g., cancer or infectious disease). PDT consists of the light excitation of a photosensitizer (PS) in the presence of O2 to yield highly reactive oxygen species. In recent years, PDT has been improved by the synthesis of targeted bioconjugates between monoclonal antibodies and PS, and by investigating PS biodistribution and PD. Here, we provide a comprehensive review of major developments in PS-immunoconjugate-based PDT and the bioanalysis of these agents, with a specific emphasis on anticancer and antimicrobial PDT. PMID:23641699

Photodynamic therapy potentiates the paracrine endothelial stimulation by colorectal cancer

NASA Astrophysics Data System (ADS)

Lamberti, María Julia; Florencia Pansa, María; Emanuel Vera, Renzo; Belén Rumie Vittar, Natalia; Rivarola, Viviana Alicia

2014-11-01

Colorectal cancer (CRC) is the third most common cancer and the third leading cause of cancer death worldwide. Recurrence is a major problem and is often the ultimate cause of death. In this context, the tumor microenvironment influences tumor progression and is considered as a new essential feature that clearly impacts on treatment outcome, and must therefore be taken into consideration. Photodynamic therapy (PDT), oxygen, light and drug-dependent, is a novel treatment modality when CRC patients are inoperable. Tumor vasculature and parenchyma cells are both potential targets of PDT damage modulating tumor-stroma interactions. In biological activity assessment in photodynamic research, three-dimensional (3D) cultures are essential to integrate biomechanical, biochemical, and biophysical properties that better predict the outcome of oxygen- and drug-dependent medical therapies. Therefore, the objective of this study was to investigate the antitumor effect of methyl 5-aminolevulinic acid-PDT using a light emitting diode for the treatment of CRC cells in a scenario that mimics targeted tissue complexity, providing a potential bridge for the gap between 2D cultures and animal models. Since photodynamic intervention of the tumor microenvironment can effectively modulate the tumor-stroma interaction, it was proposed to characterize the endothelial response to CRC paracrine communication, if one of these two populations is photosensitized. In conclusion, we demonstrated that the dialogue between endothelial and tumor populations when subjected to lethal PDT conditions induces an increase in angiogenic phenotype, and we think that it should be carefully considered for the development of PDT therapeutic protocols.

Near-infrared-absorbing gold nanopopcorns with iron oxide cluster core for magnetically amplified photothermal and photodynamic cancer therapy.

PubMed

Bhana, Saheel; Lin, Gan; Wang, Lijia; Starring, Hunter; Mishra, Sanjay R; Liu, Gang; Huang, Xiaohua

2015-06-03

We present the synthesis and application of a new type of dual magnetic and plasmonic nanostructures for magnetic-field-guided drug delivery and combined photothermal and photodynamic cancer therapy. Near-infrared-absorbing gold nanopopcorns containing a self-assembled iron oxide cluster core were prepared via a seed-mediated growth method. The hybrid nanostructures are superparamagnetic and show great photothermal conversion efficiency (η=61%) under near-infrared irradiation. Compact and stable nanocomplexes for photothermal-photodynamic therapy were formed by coating the nanoparticles with near-infrared-absorbing photosensitizer silicon 2,3-naphthalocyannie dihydroxide and stabilization with poly(ethylene glycol) linked with 11-mercaptoundecanoic acid. The nanocomplex showed enhanced release and cellular uptake of the photosensitizer with the use of a gradient magnetic field. In vitro studies using two different cell lines showed that the dual mode photothermal and photodynamic therapy with the assistance of magnetic-field-guided drug delivery dramatically improved the therapeutic efficacy of cancer cells as compared to the combination treatment without using a magnetic field and the two treatments alone. The "three-in-one" nanocomplex has the potential to carry therapeutic agents deep into a tumor through magnetic manipulation and to completely eradicate tumors by subsequent photothermal and photodynamic therapies without systemic toxicity.

In vivo 808 nm image-guided photodynamic therapy based on an upconversion theranostic nanoplatform

NASA Astrophysics Data System (ADS)

Liu, Xiaomin; Que, Ivo; Kong, Xianggui; Zhang, Youlin; Tu, Langping; Chang, Yulei; Wang, Tong Tong; Chan, Alan; Löwik, Clemens W. G. M.; Zhang, Hong

2015-09-01

A new strategy for efficient in vivo image-guided photodynamic therapy (PDT) has been demonstrated utilizing a ligand-exchange constructed upconversion-C60 nanophotosensitizer. This theranostic platform is superior to the currently reported nanophotosensitizers in (i) directly bonding photosensitizer C60 to the surface of upconversion nanoparticles (UCNPs) by a smart ligand-exchange strategy, which greatly shortened the energy transfer distance and enhanced the 1O2 production, resulting in the improvement of the therapeutic effect; (ii) realizing in vivo NIR 808 nm image-guided PDT with both excitation (980 nm) and emission (808 nm) light falling in the biological window of tissues, which minimized auto-fluorescence, reduced light scatting and improved the imaging contrast and depth, and thus guaranteed noninvasive diagnostic accuracy. In vivo and ex vivo tests demonstrated its favorable bio-distribution, tumor-selectivity and high therapeutic efficacy. Owing to the effective ligand exchange strategy and the excellent intrinsic photophysical properties of C60, 1O2 production yield was improved, suggesting that a low 980 nm irradiation dosage (351 J cm-2) and a short treatment time (15 min) were sufficient to perform NIR (980 nm) to NIR (808 nm) image-guided PDT. Our work enriches the understanding of UCNP-based PDT nanophotosensitizers and highlights their potential use in future NIR image-guided noninvasive deep cancer therapy.A new strategy for efficient in vivo image-guided photodynamic therapy (PDT) has been demonstrated utilizing a ligand-exchange constructed upconversion-C60 nanophotosensitizer. This theranostic platform is superior to the currently reported nanophotosensitizers in (i) directly bonding photosensitizer C60 to the surface of upconversion nanoparticles (UCNPs) by a smart ligand-exchange strategy, which greatly shortened the energy transfer distance and enhanced the 1O2 production, resulting in the improvement of the therapeutic effect; (ii

Use of photodynamic therapy in the treatment of bovine subclinical mastitis.

PubMed

Moreira, Lívia Helena; de Souza, José Carlos Pereira; de Lima, Carlos José; Salgado, Miguel Angel Castillo; Fernandes, Adriana Barrinha; Andreani, Dora Inés Kozusny; Villaverde, Antonio Balbin; Zângaro, Renato Amaro

2018-03-01

Bovine mastitis is a disease that causes a severe drawback in dairy production. Conventional treatments with antibiotic could leave antibiotic residues in the milk. The aim of this study was to evaluate the effect of photodynamic therapy in the treatment of bovine subclinical mastitis to develop an in vivo therapeutic protocol that could be used in routine farm practice, favoring the early return to production. Forty cows with subclinical mastitis (n = 40) were divided into 4 groups (control, photodynamic therapy - PDT, light irradiation - LED, and photosensitizer - PS). Control group received no treatment, PDT group received application of 1.0 mL of 2.5% toluidine blue photosensitizer followed by LED irradiation at λ = 635 nm, the LED group was treated with LED irradiation alone, and the PS group received only 2.5% toluidine blue dye. LED irradiation was applied to the mammary gland by means of an acrylic light guide coupled to the LED equipment. The PDT and LED groups were irradiated with 200 J/cm 2 at three different positions inside the mammary gland. Milk samples were collected at 0 h, 12 h, 24 h after treatment for microbial identification and total bacterial count. The treatment of the PDT group showed significant difference p < 0.05, characterizing the efficiency of this technique with the reduction of the microorganisms Streptococcus dysgalactiae and coagulase-negative Staphylococcus. Photodynamic therapy was effective when applied in vivo for subclinical bovine mastitis. There was no need to separate the animal from production. Copyright © 2017 Elsevier B.V. All rights reserved.

Photodynamic therapy monitoring with optical coherence angiography

NASA Astrophysics Data System (ADS)

Sirotkina, M. A.; Matveev, L. A.; Shirmanova, M. V.; Zaitsev, V. Y.; Buyanova, N. L.; Elagin, V. V.; Gelikonov, G. V.; Kuznetsov, S. S.; Kiseleva, E. B.; Moiseev, A. A.; Gamayunov, S. V.; Zagaynova, E. V.; Feldchtein, F. I.; Vitkin, A.; Gladkova, N. D.

2017-02-01

Photodynamic therapy (PDT) is a promising modern approach for cancer therapy with low normal tissue toxicity. This study was focused on a vascular-targeting Chlorine E6 mediated PDT. A new angiographic imaging approach known as M-mode-like optical coherence angiography (MML-OCA) was able to sensitively detect PDT-induced microvascular alterations in the mouse ear tumour model CT26. Histological analysis showed that the main mechanisms of vascular PDT was thrombosis of blood vessels and hemorrhage, which agrees with angiographic imaging by MML-OCA. Relationship between MML-OCA-detected early microvascular damage post PDT (within 24 hours) and tumour regression/regrowth was confirmed by histology. The advantages of MML-OCA such as direct image acquisition, fast processing, robust and affordable system opto-electronics, and label-free high contrast 3D visualization of the microvasculature suggest attractive possibilities of this method in practical clinical monitoring of cancer therapies with microvascular involvement.

Platinum(IV) complex-based two-in-one polyprodrug for a combinatorial chemo-photodynamic therapy.

PubMed

Guo, Dongbo; Xu, Shuting; Huang, Yu; Jiang, Huangyong; Yasen, Wumaier; Wang, Nan; Su, Yue; Qian, Jiwen; Li, Jing; Zhang, Chuan; Zhu, Xinyuan

2018-05-30

A combinatorial therapy that utilizes two or more therapeutic modalities is more effective in overcoming the limitations than each individual method used alone. Despite great advances have been achieved, the combination of chemotherapy and photodynamic therapy (PDT) still cannot satisfy the clinic requirements as the antitumor efficacy could be severely affected by tumor-associated hypoxia. Herein, for the first time, we reported a platinum(IV) complex-based polyprodrug that can in situ generate the highly toxic platinum(II) species as chemotherapeutics and simultaneously induce a high level of reactive oxygen species (ROS) in a PDT-like process without the use of photosensitizer and consumption of oxygen. By in situ polymerizing the platinum(IV) complex-based prodrug monomer (PPM) and 2-methacryloyloxy ethyl phosphorylcholine (MPC), nanosized hydrogel-like polyprodrug could be synthesized. Upon being exposed to light, Pt(IV) moieties in this photoactivable polyprodrug were reduced to generate Pt(II) species. At the meantime, a high level of ROS was generated without the presence of endogenous oxygen, which was confirmed by electron spin resonance (ESR) and fluorescence probes. With the unique nanosized architecture and photoresponsive feature, the as-synthesized polyprodrug exhibited the advantages of sustained drug release, long-term circulation, preferable tumor accumulation, and reversing drug resistance by downregulating the expression of multidrug resistance-associated protein 1 (MRP1) in the anticancer treatment. Copyright © 2018. Published by Elsevier Ltd.

Reflectance and fluorescence spectroscopies in photodynamic therapy

NASA Astrophysics Data System (ADS)

Finlay, Jarod C.

In vivo fluorescence spectroscopy during photodynamic therapy (PDT) has the potential to provide information on the distribution and degradation of sensitizers, the formation of fluorescent photoproducts and changes in tissue autofluorescence induced by photodynamic treatment. Reflectance spectroscopy allows quantification of light absorption and scattering in tissue. We present the results of several related studies of fluorescence and reflectance spectroscopy and their applications to photodynamic dosimetry. First, we develop and test an empirical method for the correction of the distortions imposed on fluorescence spectra by absorption and scattering in turbid media. We characterize the irradiance dependence of the in vivo photobleaching of three sensitizers, protoporphyrin IX (PpIX), Photofrin and mTHPC, in a rat skin model. The photobleaching and photoproduct formation of PpIX exhibit irradiance dependence consistent with singlet oxygen (1O2)-mediated bleaching. The bleaching of mTHPC occurs in two phases, only one of which is consistent with a 1O 2-mediated mechanism. Photofrin's bleaching is independent of irradiance, although its photoproduct formation is not. This can be explained by a mixed-mechanism bleaching model. Second, we develop an algorithm for the determination of tissue optical properties using diffuse reflectance spectra measured at a single source-detector separation and demonstrate the recovery of the hemoglobin oxygen dissociation curve from tissue-simulating phantoms containing human erythrocytes. This method is then used to investigate the heterogeneity of oxygenation response in murine tumors induced by carbogen inhalation. We find that while the response varies among animals and within each tumor, the majority of tumors exhibit an increase in blood oxygenation during carbogen breathing. We present a forward-adjoint model of fluorescence propagation that uses the optical property information acquired from reflectance spectroscopy to

ALA-PDT of the normal rat esophagus: efficiency and safety largely depends on the timing of illumination

NASA Astrophysics Data System (ADS)

van den Boogert, Jolanda; de Bruin, Ron W. F.; van Staveren, Hugo J.; Siersema, Peter D.; van Hillegersberg, Richard

1999-02-01

Photodynamic therapy (PDT) is an experimental treatment modality for (pre)malignant oesophageal lesions. 5- Aminolevulinic acid (ALA)-induced, protoporphyrin IX (PpIX)- mediated photo-sensitization could be very useful as ALA- induced porphrin accumulation selectively occurs in the oesophageal epithelium. The present study aimed to optimize the time between illumination and the administration of ALA. 200 mg/kg ALA was given orally to 24 rats (allocated to 6 groups of 4 animals each). Four animals served as controls and received phosphate buffered saline orally. The animals were illuminated at various time-points (either 1, 2, 3, 4, 6, or 12 hours) after ALA administration. Illumination was performed with a cylindrical diffuser placed in a balloon catheter. The device was originally made for percutaneous transluminal coronary angioplasty and consisted of a semi-flexible catheter and an inflatable cylindric optically clear balloon. The diffuser was placed centrally in the catheter. The same illumination parameters (633 nm, 25 J radiant energy/cm diffuser, power output 100 mW/cm diffuser) were used for each animal. During illumination, fluorescence measurements and light dosimetry were performed. The animals were sacrificed at 48 hours after PDT for histological assessment. Highest PpIX fluorescence was found at 2, 3, and 4 hours after ALA administration. Dosimetric measurements showed a 2 - 3 times higher in vivo fluence rate compared to the estimated fluence rate. Histology at 48 hours after PDT showed diffuse epithelial damage at the laser site only in rats illuminated at 2 hours after ALA administration. Illumination at 3, 4, and 6 hours after ALA administration resulted in diffuse epithelial damage in only one of four rats. In none of the rats illuminated at 1 and 12 hours after administration of ALA epithelial damage was found. These results show that illumination at 2 hours after oral ALA administration provides an efficient and safe scheme for ALA-PDT in the

Combination photodynamic therapy of human breast cancer using salicylic acid and methylene blue

NASA Astrophysics Data System (ADS)

Hosseinzadeh, Reza; Khorsandi, Khatereh; Jahanshiri, Maryam

2017-09-01

The objective of this study was to evaluate the effects of combination therapy with methylene blue (MB) assisted photodynamic therapy (PDT) and salicylic acid (SA) as chemo-therapy anticancer agent. The binding of salicylic acid to methylene blue was studied using spectrophotometric method. The results show the 1:2 complex formation between SA and MB. The binding constants and related Gibbs free energies o are obtained (Kb1 = 183.74, Kb2 = 38.13 and ∆ Gb1° = 12.92 kJ·mol- 1, ∆ Gb2° =9.02 kJ·mol- 1). The spectrophotometric results show the improvement in solubilization and reduction prevention for SA and MB in the complex form. These results are in agreements with cellular experiments. The dark toxicity measurements represent the improve efficacy of chemotherapy using combination of SA and MB. The photodynamic therapy results (using red LED as light source (630 nm; power density: 30 mW cm- 2)) show that the cancer cell killing efficiency of MB increases in the combination with SA due to reduction prevention and stabilization of monomeric form of MB.

Lethality In Mice Following Localized Photodynamic Therapy

NASA Astrophysics Data System (ADS)

Ferrario, Angela; Gomer, Charles J.; Murphree, A. L.

1989-06-01

Porphyrin photodynamic therapy directed specifically to the hind leg of various strains of mice was found to induce a high percentage of lethality at dosages which would be required to achieve cures in tumor bearing mice. Toxicity was observed in both pigmented and albino mouse strains. An inverse relationship between light dose rate and lethality was documented. Anti-coagulant drugs and anti-inflammatory agents which inhibit cyclo-oxygenase had protective effects. The response induced by localized PDT appears to mimic that of a classical traumatic shock syndrome and may be limited to PDT in small animals such as mice.

In vitro evaluation of photodynamic therapy using curcumin on Leishmania major and Leishmania braziliensis.

PubMed

Pinto, Juliana Guerra; Fontana, Letícia Correa; de Oliveira, Marco Antonio; Kurachi, Cristina; Raniero, Leandro José; Ferreira-Strixino, Juliana

2016-07-01

Cutaneous leishmaniasis is an infectious disease caused by the Leishmania protozoan. The conventional treatment is long-lasting and aggressive, in addition to causing harmful effect. Photodynamic therapy has emerged as a promising alternative treatment, which allows local administration with fewer side effects. This study investigated the photodynamic activity of curcumin on Leishmania major and Leishmania braziliensis promastigote. Both species were submitted to incubation with curcumin in serial dilutions from 500 μg/ml up to 7.8 μg/ml. Control groups were kept in the dark while PDT groups received a fluency of 10 J/cm(2) at 450 nm. Mitochondrial activity was assessed by MTT assay 18 h after light treatment, and viability was measured by Trypan blue dye exclusion test. Morphological alterations were observed by Giemsa staining. Confocal microscopy showed the uptake of curcumin by both tested Leishmania species. Mitochondrial activity was inconclusive to determine viability; however, Trypan blue test was able to show that curcumin photodynamic treatment had a significant effect on viability of parasites. The morphology of promastigotes was highly affected by the photodynamic therapy. These results indicated that curcumin may be a promising alternative photosensitizer, because it presents no toxicity in the dark; however, further tests in co-culture with macrophages and other species of Leishmania should be conducted to determine better conditions before in vivo tests are performed.

ALA-PDT elicits oxidative damage and apoptosis in UVB-induced premature senescence of human skin fibroblasts.

PubMed

Zhou, Bing-Rong; Zhang, Li-Chao; Permatasari, Felicia; Liu, Juan; Xu, Yang; Luo, Dan

2016-06-01

5-Aminolevulinic acid photodynamic therapy (ALA-PDT) has been used for the treatment of skin photoaging. It can significantly improve the appearance of fine lines, dotted pigmentation, and roughness of photoaged skin. However, the mechanisms by which ALA-PDT yields rejuvenating effects on photoaged skin have not been well elucidated. Thus, in this study we explored the effects of ALA-PDT in photoaged fibroblasts. We established a stress-induced premature senescence (SIPS) model by repeated exposures of human dermal fibroblasts (HDFs) to ultraviolet B (UVB) irradiation. Cells were irradiated by red light laser at 635nm wavelength (50mW/cm(2)). Intracellular protoporphyrin IX (PpIX) was detected by confocal microscopy. Intracellular reactive oxygen species (ROS) level and mitochondrial membrane potential (MMP) change were detected by fluorescence microscopy and flow cytometry. Morphological changes were observed by optical microscopy. Proliferative activity was measured by a cell counting kit-8 (CCK-8). Cell apoptosis was detected by fluorescence microscopy using Hoechst staining and flow cytometry using annexin V/propidium Iodide double staining. Intracellular PpIX fluorescence in UVB-induced premature senescent HDFs (UVB-SIPS-HDFs) reached the highest intensity after incubation with 1.00mmol/L ALA for 6h (P<0.05). Compared with control group, intracellular ROS level, MMP, and apoptotic rate were increased (P<0.05) and proliferative activity was decreased (P<0.05) in UVB-SIPS-HDFs treated with ALA-PDT, which were positively correlated to ALA incubation time and red light laser dose. Our study demonstrated that ALA-PDT elicits oxidative damage and apoptosis in photoaged fibroblasts in vitro, which may be the basis for the rejuvenating effects on photoaged skin. Copyright © 2016 Elsevier B.V. All rights reserved.

Interstitial photodynamic therapy and glioblastoma: light fractionation study on a preclinical model: preliminary results

NASA Astrophysics Data System (ADS)

Leroy, Henri-Arthur; Vermandel, Maximilien; Tétard, Marie-Charlotte; Lejeune, Jean-Paul; Mordon, Serge; Reyns, Nicolas

2015-03-01

Background Glioblastoma is a high-grade cerebral tumor with local recurrence and poor outcome. Photodynamic therapy (PDT) is a local treatment based on the light activation of a photosensitizer (PS) in the presence of oxygen to form cytotoxic species. Fractionation of light delivery may enhance treatment efficiency by restoring tissue oxygenation. Objectives To evaluate the efficiency of light fractionation using MRI imaging, including diffusion and perfusion, compared to histological data. Materials and Methods Thirty-nine "Nude" rats were grafted with human U87 cells into the right putamen. After PS precursor intake (5-ALA), an optic fiber was introduced into the tumor. The rats were randomized in three groups: without illumination, with monofractionated illumination and the third one with multifractionated light. Treatment effects were assessed with early MRI including diffusion and perfusion sequences. The animals were eventually sacrificed to perform brain histology. Results On MRI, we observed elevated diffusion values in the center of the tumor among treated animals, especially in multifractionated group. Perfusion decreased around the treatment site, all the more in the multifractionated group. Histology confirmed our MRI findings, with a more extensive necrosis and associated with a rarified angiogenic network in the treatment area, after multifractionated PDT. However, we observed more surrounding edema and neovascularization in the peripheral ring after multifractionated PDT. Conclusion Fractionated interstitial PDT induced specific tumoral lesions. The multifractionated scheme was more efficient, inducing increased tumoral necrosis, but it also caused significant peripheral edema and neovascularization. Diffusion and perfusion MRI imaging were able to predict the histological lesions.

Performance of a contact textile-based light diffuser for photodynamic therapy.

PubMed

Khan, Tania; Unternährer, Merthan; Buchholz, Julia; Kaser-Hotz, Barbara; Selm, Bärbel; Rothmaier, Markus; Walt, Heinrich

2006-03-01

Medical textiles offer a unique contact opportunity that could provide value-added comfort, reliability, and safety for light or laser-based applications. We investigated a luminous textile diffuser for use in photodynamic therapy. Textile diffusers are produced by an embroidery process. Plastic optical fibers are bent and sewn into textile to release light by macrobending. A reflective backing is incorporated to improve surface homogeneity, intensity, and safety. Clonogenic assay (MCF-7 cells) and trypan blue exclusion (NuTu19 cells) tests were performed in vitro using 0.1μg/ml m-THPC with three textile diffusers and a standard front lens diffuser. Heating effects were studied in solution and on human skin. PDT application in vivo was performed with the textile diffuser on equine sarcoids (three animals, 50mW/cm(2), 10-20J) and eight research animals. Lastly, computer simulations were performed to see how the textile diffuser might work on a curved object. At low fluency rate, there is a trend for the textile diffuser to have lower survival rates than the front lens diffuser for both cell lines. The textile diffuser was observed to retain more heat over a long period (>1min). All animals tolerated the treatments well and showed similar initial reactions. The simulations showed a likely focusing effect in a curved geometry. The initial feasibility and application using a textile-based optical diffuser has been demonstrated. Possibilities that provide additional practical advantages of the textile diffuser are discussed.

Possibility for a full optical determination of photodynamic therapy outcome

NASA Astrophysics Data System (ADS)

Vollet-Filho, J. D.; Menezes, P. F. C.; Moriyama, L. T.; Grecco, C.; Sibata, C.; Allison, R. R.; Castro e Silva, O.; Bagnato, V. S.

2009-05-01

The efficacy of photodynamic therapy (PDT) depends on a variety of parameters: concentration of the photosensitizer at the time of treatment, light wavelength, fluence, fluence rate, availability of oxygen within the illuminated volume, and light distribution in the tissue. Dosimetry in PDT requires the congregation of adequate amounts of light, drug, and tissue oxygen. The adequate dosimetry should be able to predict the extension of the tissue damage. Photosensitizer photobleaching rate depends on the availability of molecular oxygen in the tissue. Based on photosensitizers photobleaching models, high photobleaching has to be associated with high production of singlet oxygen and therefore with higher photodynamic action, resulting in a greater depth of necrosis. The purpose of this work is to show a possible correlation between depth of necrosis and the in vivo photosensitizer (in this case, Photogem®) photodegradation during PDT. Such correlation allows possibilities for the development of a real time evaluation of the photodynamic action during PDT application. Experiments were performed in a range of fluence (0-450 J/cm2) at a constant fluence rate of 250 mW/cm2 and applying different illumination times (0-1800 s) to achieve the desired fluence. A quantity was defined (ψ) as the product of fluorescence ratio (related to the photosensitizer degradation at the surface) and the observed depth of necrosis. The correlation between depth of necrosis and surface fluorescence signal is expressed in ψ and could allow, in principle, a noninvasive monitoring of PDT effects during treatment. High degree of correlation is observed and a simple mathematical model to justify the results is presented.

Photodynamic therapy as a new approach to Trichomonas vaginalis inactivation.

PubMed

Silva Fonseca, Thaisa Helena; Alacoque, Marina; Silva Oliveira, Fabrício Marcus; Soares, Betânia Maria; Leite, Henrique Vitor; Caliari, Marcelo Vidigal; Gomes, Maria Aparecida; Busatti, Haendel

2018-06-01

The emergence of nitroimidazole resistant isolates has been an aggravating factor in the treatment of trichomoniasis, the most common non-viral sexually transmitted disease in the world. This highlights the importance of new technologies that are safe, effective, and have minor side effects or resistance. Hence, we evaluated the effectiveness of photodynamic therapy on the inactivation of Trichomonas vaginalis in vitro. We used methylene blue as a photosensitizing substance, and a light-emitting diode (LED) for irradiation of metronidazole sensitive and resistant strains. Our results showed that only the presence of light did not interfere with parasite growth; however, methylene blue isolated or associated with light inhibited 31.78% ± 7.18 and 80.21% ± 7.11 of the sensitive strain, respectively, and 31.17% ± 4.23 and 91.13% ± 2.31 of the resistant strain, respectively. The high trichomonicidal activity of the photodynamic therapy, associated with low cost and ease of application, signalize its great therapeutic potential not only when conventional treatment fails, but also routinely in women with trichomoniasis. Copyright © 2018 Elsevier B.V. All rights reserved.

Chemotherapy-Induced Macrophage Infiltration into Tumors Enhances Nanographene-Based Photodynamic Therapy.

PubMed

Zhao, Yang; Zhang, Chenran; Gao, Liquan; Yu, Xinhe; Lai, Jianhao; Lu, Dehua; Bao, Rui; Wang, Yanpu; Jia, Bing; Wang, Fan; Liu, Zhaofei

2017-11-01

Increased recruitment of tumor-associated macrophages (TAM) to tumors following chemotherapy promotes tumor resistance and recurrence and correlates with poor prognosis. TAM depletion suppresses tumor growth, but is not highly effective due to the effects of tumorigenic mediators from other stromal sources. Here, we report that adoptive macrophage transfer led to a dramatically enhanced photodynamic therapy (PDT) effect of 2-(1-hexyloxyethyl)-2-devinyl pyropheophor-bide-alpha (HPPH)-coated polyethylene glycosylated nanographene oxide [GO(HPPH)-PEG] by increasing its tumor accumulation. Moreover, tumor treatment with commonly used chemotherapeutic drugs induced an increase in macrophage infiltration into tumors, which also enhanced tumor uptake and the PDT effects of GO(HPPH)-PEG, resulting in tumor eradication. Macrophage recruitment to tumors after chemotherapy was visualized noninvasively by near-infrared fluorescence and single-photon emission CT imaging using F4/80-specific imaging probes. Our results demonstrate that chemotherapy combined with GO(HPPH)-PEG PDT is a promising strategy for the treatment of tumors, especially those resistant to chemotherapy. Furthermore, TAM-targeted molecular imaging could potentially be used to predict the efficacy of combination therapy and select patients who would most benefit from this treatment approach. Cancer Res; 77(21); 6021-32. ©2017 AACR . ©2017 American Association for Cancer Research.

Comparison of 10 efficient protocols for photodynamic therapy of actinic keratosis: How relevant are effective light dose and local damage in predicting the complete response rate at 3 months?

PubMed

Vignion-Dewalle, Anne-Sophie; Baert, Gregory; Thecua, Elise; Lecomte, Fabienne; Vicentini, Claire; Abi-Rached, Henry; Mortier, Laurent; Mordon, Serge

2018-04-18

Topical photodynamic therapy is an established treatment modality for various dermatological conditions, including actinic keratosis. In Europe, the approved protocols for photodynamic therapy of actinic keratosis involve irradiation with either an Aktilite CL 128 lamp or daylight, whereas irradiation with the Blu-U illuminator is approved in the United States. Many other protocols using irradiation by a variety of light sources are also clinically efficient. This paper aims to compare 10 different protocols with clinically proven efficacy for photodynamic therapy of actinic keratosis and the available spectral irradiance of the light source. Effective irradiance, effective light dose, and local damage are compared. We also investigate whether there is an association between the complete response rate at 3 months and the effective light dose or local damage. The effective irradiance, also referred to as protoporphyrin IX-weighted irradiance, is obtained by integrating the spectral irradiance weighted by the normalized absorption spectrum of protoporphyrin IX over the wavelength. Integrating the effective irradiance over the irradiation time yields the effective light dose, which is also known as the protoporphyrin IX-weighted light dose. Local damage, defined as the total cumulative singlet oxygen molecules produced during treatment, is estimated using mathematical modeling of the photodynamic therapy process. This modeling is based on an iterative procedure taking into account the spatial and temporal variations in the protoporphyrin IX absorption spectrum during treatment. The protocol for daylight photodynamic therapy on a clear sunny day, the protocol for daylight photodynamic therapy on an overcast day, the photodynamic therapy protocol for a white LED lamp for operating rooms and the photodynamic therapy protocol for the Blu-U illuminator perform better than the six other protocols-all involving red light illumination-in terms of both effective light dose and

Photodynamic therapy: the role of paraptosis

NASA Astrophysics Data System (ADS)

Kessel, David; Cho, Won-Jin; Kim, Hyeong-Reh

2018-02-01

Apoptosis is a pathway to cell death frequently observed after photodynamic therapy (PDT). Sub-cellular photodamage to mitochondria, lysosomes, the ER, or combinations of these targets, can lead to apoptotic death. We have recently investigated another pathway to cell death after PDT termed `paraptosis'. This is characterized by extensive cytoplasmic vacuolization, does not involve caspase activation or nuclear fragmentation, requires a brief interval of continued protein synthesis and appears to derive from ER stress. Determinants and further characteristics of PDT-derived paraptosis are explored in the A549 non small-cell lung cancer cell line and in cells derived from head and neck cancer tissues. We provide evidence that ER photodamage and JNK pathway activation are involved in PDT-mediated paraptosis.

Bioluminescence-Activated Deep-Tissue Photodynamic Therapy of Cancer

PubMed Central

Kim, Yi Rang; Kim, Seonghoon; Choi, Jin Woo; Choi, Sung Yong; Lee, Sang-Hee; Kim, Homin; Hahn, Sei Kwang; Koh, Gou Young; Yun, Seok Hyun

2015-01-01

Optical energy can trigger a variety of photochemical processes useful for therapies. Owing to the shallow penetration of light in tissues, however, the clinical applications of light-activated therapies have been limited. Bioluminescence resonant energy transfer (BRET) may provide a new way of inducing photochemical activation. Here, we show that efficient bioluminescence energy-induced photodynamic therapy (PDT) of macroscopic tumors and metastases in deep tissue. For monolayer cell culture in vitro incubated with Chlorin e6, BRET energy of about 1 nJ per cell generated as strong cytotoxicity as red laser light irradiation at 2.2 mW/cm2 for 180 s. Regional delivery of bioluminescence agents via draining lymphatic vessels killed tumor cells spread to the sentinel and secondary lymph nodes, reduced distant metastases in the lung and improved animal survival. Our results show the promising potential of novel bioluminescence-activated PDT. PMID:26000054

Graphene quantum dots with nitrogen-doped content dependence for highly efficient dual-modality photodynamic antimicrobial therapy and bioimaging.

PubMed

Kuo, Wen-Shuo; Chen, Hua-Han; Chen, Shih-Yao; Chang, Chia-Yuan; Chen, Pei-Chi; Hou, Yung-I; Shao, Yu-Ting; Kao, Hui-Fang; Lilian Hsu, Chih-Li; Chen, Yi-Chun; Chen, Shean-Jen; Wu, Shang-Rung; Wang, Jiu-Yao

2017-03-01

Reactive oxygen species is the main contributor to photodynamic therapy. The results of this study show that a nitrogen-doped graphene quantum dot, serving as a photosensitizer, was capable of generating a higher amount of reactive oxygen species than a nitrogen-free graphene quantum dot in photodynamic therapy when photoexcited for only 3 min of 670 nm laser exposure (0.1 W cm -2 ), indicating highly improved antimicrobial effects. In addition, we found that higher nitrogen-bonding compositions of graphene quantum dots more efficiently performed photodynamic therapy actions than did the lower compositions that underwent identical treatments. Furthermore, the intrinsically emitted luminescence from nitrogen-doped graphene quantum dots and high photostability simultaneously enabled it to act as a promising contrast probe for tracking and localizing bacteria in biomedical imaging. Thus, the dual modality of nitrogen-doped graphene quantum dots presents possibilities for future clinical applications, and in particular multidrug resistant bacteria. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effectiveness of 5-aminolevulinic acid photodynamic therapy in the treatment of hidradenitis suppurativa: a report of 5 cases.

PubMed

Andino Navarrete, R; Hasson Nisis, A; Parra Cares, J

2014-01-01

Hidradenitis suppurativa has been described as a chronic, recurrent, and disabling inflammatory disease involving the entire hair follicle. Several treatments, including photodynamic therapy, have been used, but the results have been inconsistent and recurrence is high. In this prospective study, we evaluated disease severity, quality of life, and treatment tolerance in 5 patients with moderate to severe hidradenitis suppurativa treated with photodynamic therapy using 5-aminolevulinic acid and a 635-nm light source. Treatment effectiveness was evaluated using the Sartorius severity score, the Dermatology Life Quality Index, and a visual analog scale for pain and disease activity. Significant improvements were observed with all 3 instruments and the effects remained visible at 8 weeks. Our results suggest that photodynamic therapy with 5-aminolevulinic acid and a light wavelength of 635 nm could reduce disease severity and improve quality of life in patients with difficult-to-treat hidradenitis suppurativa. Copyright © 2013 Elsevier España, S.L. y AEDV. All rights reserved.

Plasmonic enhancement of cyanine dyes for near-infrared light-triggered photodynamic/photothermal therapy and fluorescent imaging

NASA Astrophysics Data System (ADS)

Lu, Mindan; Kang, Ning; Chen, Chuan; Yang, Liuqing; Li, Yang; Hong, Minghui; Luo, Xiangang; Ren, Lei; Wang, Xiumin

2017-11-01

Near-infrared (NIR) triggered cyanine dyes have attracted considerable attention in multimodal tumor theranostics. However, NIR cyanine dyes used in tumor treatment often suffer from low fluorescence intensity and weak singlet oxygen generation efficiency, resulting in inadequate diagnostic and therapy efficacy for tumors. It is still a great challenge to improve both the photodynamic therapy (PDT) and fluorescent imaging (FLI) efficacy of cyanine dyes in tumor applications. Herein, a novel multifunctional nanoagent AuNRs@SiO2-IR795 was developed to realize the integrated photothermal/photodynamic therapy (PTT/PDT) and FLI at a very low dosage of IR795 (0.4 μM) based on metal-enhanced fluorescence (MEF) effects. In our design, both the fluorescence intensity and reactive oxygen species of AuNRs@SiO2-IR795 nanocomposites were significantly enhanced up to 51.7 and 6.3 folds compared with free IR795, owing to the localized surface plasmon resonance band of AuNRs overlapping with the absorption or fluorescence emission band of the IR795 dye. Under NIR laser irradiation, the cancer cell inhibition efficiency in vitro with synergetic PDT/PTT was up to 82.3%, compared with 10.3% for free IR795. Moreover, the enhanced fluorescence intensity of our designed nanocomposites was helpful to track their behavior in tumor cells. Therefore, our designed nanoagents highlight the applications of multimodal diagnostics and therapy in tumors based on MEF.

A new optical intra-tissue fiber irradiation ALA-PDT in the treatment of acne vulgaris in rabbit model: improved safety and tolerability.

PubMed

Wang, Qian; Jiang, Can; Liu, Wei; Chen, Jin; Lin, Xinyu; Huang, Xiangning; Duan, Xiling

2017-01-01

Photodynamic therapy with topical aminolevulinic acid (ALA-PDT) has been suggested to be effective in treatment of acne vulgaris. However, adverse events occur during and after treatment. To compare the efficacy and tolerability of optical intra-tissue fiber irradiation (OFI) ALA-PDT versus traditional ALA-PDT in treatment of acne vulgaris in rabbit models. Twenty-five rabbits of clean grade were used. Twenty rabbits were randomly selected to establish acne model and the other five were used as control. Rabbits in model group (40 ears) were further divided into four groups (10 ears/group): I, OFI-ALA-PDT with the head of optical fiber inserted into the target lesion (intra-tissue); II, traditional ALA-PDT group; III, OFI group; IV, blank control group without any treatment. Uncomfortable symptoms, adverse events, and effectiveness rates were recorded on post-treatment day 14, 30, and 45. On post-treatment day 14, the effectiveness rate in OFI-ALA-PDT group was obviously higher than that of the other three groups (P<0.05). However, no improved effects were observed in OFI-ALA-PDT group on day 30 and 45. During the period of treatment, the frequencies of uncomfortable symptoms in ALA-PDT group were obviously higher than those in the other three groups (P<0.05). The adverse event rate in OFI-ALA-PDT group was obviously lower than that of the ALA-PDT group (P<0.05). The unblindness of the study and temporary animal models of acne induced may hamper the assessment and monitoring of the results, and future studies are still needed to clarify it further. The OFI-ALA-PDT group (intra-tissue irradiation) showed no improved efficacy on treating rabbit ear acne but had higher safety and better tolerability.

Photodynamic therapy for endodontic disinfection.

PubMed

Soukos, Nikolaos S; Chen, Peter Shih-Yao; Morris, Jason T; Ruggiero, Karriann; Abernethy, Abraham D; Som, Sovanda; Foschi, Federico; Doucette, Stephanie; Bammann, Lili Luschke; Fontana, Carla Raquel; Doukas, Apostolos G; Stashenko, Philip P

2006-10-01

The aims of this study were to investigate the effects of photodynamic therapy (PDT) on endodontic pathogens in planktonic phase as well as on Enterococcus faecalis biofilms in experimentally infected root canals of extracted teeth. Strains of microorganisms were sensitized with methylene blue (25 microg/ml) for 5 minutes followed by exposure to red light of 665 nm with an energy fluence of 30 J/cm2. Methylene blue fully eliminated all bacterial species with the exception of E. faecalis (53% killing). The same concentration of methylene blue in combination with red light (222 J/cm2) was able to eliminate 97% of E. faecalis biofilm bacteria in root canals using an optical fiber with multiple cylindrical diffusers that uniformly distributed light at 360 degrees. We conclude that PDT may be developed as an adjunctive procedure to kill residual bacteria in the root canal system after standard endodontic treatment.

Determination of fluence rate and temperature distributions in the rat brain; implications for photodynamic therapy.

PubMed

Angell-Petersen, Even; Hirschberg, Henry; Madsen, Steen J

2007-01-01

Light and heat distributions are measured in a rat glioma model used in photodynamic therapy. A fiber delivering 632-nm light is fixed in the brain of anesthetized BDIX rats. Fluence rates are measured using calibrated isotropic probes that are positioned stereotactically. Mathematical models are then used to derive tissue optical properties, enabling calculation of fluence rate distributions for general tumor and light application geometries. The fluence rates in tumor-free brains agree well with the models based on diffusion theory and Monte Carlo simulation. In both cases, the best fit is found for absorption and reduced scattering coefficients of 0.57 and 28 cm(-1), respectively. In brains with implanted BT(4)C tumors, a discrepancy between diffusion and Monte Carlo-derived two-layer models is noted. Both models suggest that tumor tissue has higher absorption and less scattering than normal brain. Temperatures are measured by inserting thermocouples directly into tumor-free brains. A model based on diffusion theory and the bioheat equation is found to be in good agreement with the experimental data and predict a thermal penetration depth of 0.60 cm in normal rat brain. The predicted parameters can be used to estimate the fluences, fluence rates, and temperatures achieved during photodynamic therapy.

Photodynamic therapy with simultaneous suppression of multiple treatment escape pathways (Conference Presentation)

NASA Astrophysics Data System (ADS)

Spring, Bryan Q.; Sears, R. Bryan; Zheng, Lei Z.; Mai, Zhiming; Watanabe, Reika; Sherwood, Margaret E.; Schoenfeld, David A.; Pogue, Brian W.; Pereira, Stephen P.; Villa, Elizabeth; Hasan, Tayyaba

2016-03-01

We introduce photoactivatable multi-inhibitor nanoliposomes (PMILs) for photodynamic tumor cell and microvessel damage in synchrony with photo-initiation of tumor-confined, multikinase inhibitor release. The PMIL is a biodegradable delivery system comprised of a nanoliposome carrying a photoactivable chromophore (benzoporphyrin derivative monoacid A, BPD) in its bilayer. A multikinase inhibitor-loaded PEG-PLGA nanoparticle is encapsulated within the liposome, which acts a barrier to nanoparticle erosion and drug release. Following intravenous PMIL administration, near infrared irradiation of tumors triggers photodynamic therapy and initiates tumor-confined drug release from the nanoparticle. This talk presents promising preclinical data in mouse models of pancreatic cancer utilizing this concept to suppress the VEGF and MET signaling pathways—both critical to cancer progression, metastasis and treatment escape. A single PMIL treatment using low doses of a multikanse inhibitor (cabozantinib, XL184) achieves sustained tumor reduction and suppresses metastatic escape, whereas combination therapy by co-administration of the individual agents has significantly reduced efficacy. The PMIL concept is amenable to a number of molecular inhibitors and offers new prospects for spatiotemporal synchronization of combination therapies whilst reducing systemic drug exposure and associated toxicities.

Anti-angiogenic treatment (Bevacizumab) improves the responsiveness of photodynamic therapy in colorectal cancer.

PubMed

Peng, Cheng-Liang; Lin, Hua-Ching; Chiang, Wei-Lun; Shih, Ying-Hsia; Chiang, Ping-Fang; Luo, Tsai-Yueh; Cheng, Chun-Chia; Shieh, Ming-Jium

2018-06-09

Photodynamic therapy (PDT) is a new treatment utilizing the combined action of photosensitizers and light for the treatment of various cancers. The mechanisms for tumor destruction after PDT include direct tumor cell kill by singlet oxygen species (OS), indirect cell kill via vascular damage, and an elicited immune response. However, it has been reported that many cellular activators, including vascular endothelial growth factor (VEGF), are produced by tumor cells after PDT. In this study, we demonstrate that meta-tetra(hydroxyphenyl) chlorin (mTHPC)-based photodynamic therapy combined with bevacizumab (Avastin™), an anti-VEGF neutralizing monoclonal antibody that blocks the binding of VEGF to its receptor, can enhance the effectiveness of each treatment modality. We evaluated the efficacy of bevacizumab-based anti-angiogenesis in combination with PDT as well as the resulting VEGF levels in a mouse model of human colon cancer. Enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) were performed to assess VEGF concentrations in the various treatment groups, and confocal imaging and high performance liquid chromatography (HPLC) analyses were used to measure the distribution and concentration of mTHPC in tumors. Our results demonstrate that combination of PDT followed by bevacizumab significantly elicits a greater tumor response whereas bevacizumab treatment prior to PDT led to a reduced tumor response. Immunostaining and ELISA analyses revealed a lower expression of VEGF in tumors treated with combination therapy of PDT followed by bevacizumab. However, bevacizumab treatment decreased the accumulation of mTHPC in tumors 24 h after administration, which complemented the results of decreased anti-tumor efficacy of bevacizumab followed by PDT. Copyright © 2018. Published by Elsevier B.V.

[Effect of M007 mediated photodynamic therapy on proliferation of human osteosarcoma MG63 cells in vitro].

PubMed

Zhou, Yu-Kai; Wu, Wen-Zhi; Zhang, Lan; Yang, Chun-Hui; Wang, Yan-Ping

2012-01-01

To investigate the effect of a new photosensitizer, M007 mediated photodynamic therapy on proliferation of human osteosarcoma MG63 cells in vitro. Human osteosarcoma MG63 cells were prepared as 1 x 10(6) /mL single-cell suspension, and 1 mL cells were transferred into 60 mL culture dish, then treated with 5 different gradient dosages (0, 2, 4, 8, 16 micromol/L) of M007 followed by photodynamic therapy or dark reaction for 10 min. The survival rate of the cells and the mode of cell death were detected by flow cytometry with the stain of Annexin V-FITC/PI. The effect on proliferation of survival cells was observed by MTT assay and colony-forming assay. M007 mediated photodynamic therapy induced the inactivation of MG63 human osteosarcoma cells in the way of late apoptosis/necrosis or becoming naked nucleus predominately. More than 90% MG63 cells in M007-PDT group were dead under the treatment of 2-16 micromol/L M007. The survival rates of 4-16 micromol/L M007-PDT group were steadily less than 1%. The optical densities did not increase with extension of culture time in 2-8 micromol/L M007-PDT group (P > 0.05). There were 16 survival alive cells found occasionally in 2 micromol/L M007-PDT group, but no colonies found in other groups. M007 mediated photodynamic therapy totally inactivated human osteosarcoma MG63 cells in vitro with the dosage more than 4 micromol/L.

Photodynamic Therapy for Gynecological Diseases and Breast Cancer

PubMed Central

Shishkova, Natashis; Kuznetsova, Olga; Berezov, Temirbolat

2012-01-01

Photodynamic therapy (PDT) is a minimally invasive and promising new method in cancer treatment. Cytotoxic reactive oxygen species (ROS) are generated by the tissue-localized non-toxic sensitizer upon illumination and in the presence of oxygen. Thus, selective destruction of a targeted tumor may be achieved. Compared with traditional cancer treatment, PDI has advantages including higher selectivity and lower rate of toxicity. The high degree of selectivity of the proposed method was applied to cancer diagnosis using fluorescence. This article reviews previous studies done on PDT treatment and photodetection of cervical intraepithelial neoplasia, vulvar intraepithelial neoplasia, ovarian and breast cancer, and PDT application in treating non-cancer lesions. The article also highlights the clinical responses to PDT, and discusses the possibility of enhancing treatment efficacy by combination with immunotherapy and targeted therapy. PMID:23691448

Intravesical dosimetry applied to laser positioning in photodynamic therapy

NASA Astrophysics Data System (ADS)

Beslon, Guillaume; Ambroise, Philippe; Heit, Bernard; Bremont, Jacques; Guillemin, Francois H.

1996-12-01

Superficial bladder tumor is a challenging indication for photodynamic therapy. Due to lack of specificity of the sensitizers, the light has to be precisely monitored over the bladder surface, illuminated by an isotropic source, to restrict the cytotoxic effect to the tumor without affecting the normal epithelium. In order to assist the surgeon while processing the therapy, an urothelium illumination model is proposed. It is computed through a spline interpolation, on the basis of 12 intravesical sensors. This paper presents the overall system architecture and details the modelization and visualization processes. With this model, the surgeon is able to master the source displacement inside the bladder and to homogenize the tissue exposure.

Overcoming photodynamic resistance and tumor targeting dual-therapy mediated by indocyanine green conjugated gold nanospheres.

PubMed

Li, Wei; Guo, Xiaomeng; Kong, Fenfen; Zhang, Hanbo; Luo, Lihua; Li, Qingpo; Zhu, Chunqi; Yang, Jie; Du, Yongzhong; You, Jian

2017-07-28

Photodynamic therapy (PDT) and photothermal therapy (PTT) have captured much attention due to the great potential to cure malignant tumor. Nevertheless, photodynamic resistance of cancer cells has limited the further efficacy of PDT. Unfortunately, the resistance mechanism and efforts to overcome the resistance still have been rarely reported so far. Here, we report a nanosystem with specific tumor targeting for combined PDT and PTT mediated by near-infrared (NIR) light, which was established by covalently conjugating indocyanine green (ICG) and TNYL peptide onto the surface of hollow gold nanospheres (HAuNS). Our nanosystem (TNYL-ICG-HAuNS) was proved to possess significantly increased light stability, reactive oxygen species (ROS) production and photothermal effect under NIR light irradiation, thus presenting a remarkably enhanced antitumor efficacy. The up-regulation of nuclear factor erythroid 2-related factor 2 (NFE2L2, Nrf2) in cancer cells during PDT induced a significant increase of ABCG2, NQO-1 and HIF-1α expression, causing PDT resistance of the cells. Interestingly, ABCG2 expression could almost keep a normal level in the whole PDT process mediated by TNYL-ICG-HAuNS. After repeated irradiations, TNYL-ICG-HAuNS could still produce almost constant ROS in cells while the Nrf2 expression reduced significantly. Furthermore, PDT resistance induced an obvious decrease of the internalization of free ICG, but didn't influence the cell uptake of TNYL-ICG-HAuNS. Our data explained that TNYL-ICG-HAuNS could overcome the photodynamic resistance of cancer cells, acting as a promising modality for simultaneous photothermal and photodynamic cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Treatment of complicated gangrene using infrared photodynamic therapy

NASA Astrophysics Data System (ADS)

Szabo, Robert

2018-04-01

Antimicrobial photodynamic therapy (aPDT) is one of the treatment options of local infections. Conventional aPDT systems have physical limitations such as low light penetration and the need for long irradiation time to achieve the necessary light dose. With new forming specific complex of methylene blue dye molecules it is possible to reach efficient excitation processes at 810nm. At 810nm, there is increased light penetration depth in comparison to 670nm. This means that we are now able to excite the sensitizer in deeper areas and activate it transgingivally. Purpose Preserving teeth with complicated gangrene is a great challenge if root canal is obstructed. Lacking the possibility to perform the conventional mechanical cleaning of root canals. we have used infrared photodynamic therapy for elimination radicular bacterial infiltration Materials and methods We investigated 14 cases with complicated gangrene and totally or partially obstructed root canal. We deposited the sensitizer - Photolase Photolase GMBH Germany - in the pulp chamber and closed it for a week. This procedure was repeated three times. After the sensitizer penetrated we applied the light. We used G-Box 810 nm laser - Gigaa Laser China - at 0,8W/cm2 , 40s buccal and 40s oral side. Results 6 month later we performed follow-up CBCT. Out of 14 cases significant healing was detected in 10. In 4 cases no change was observable. Discussion and conclusion Infrared aPDT seems effective in eliminating bacterial infiltrations in deeper areas. It can be a minimal invasive method in the case of obstructed root canals.

Influence of protoporphyrin IX loaded phloroglucinol succinic acid dendrimer in photodynamic therapy

NASA Astrophysics Data System (ADS)

Kumar, M. Suresh; Aruna, P.; Ganesan, S.

2018-03-01

One of the major problems reported clinically for photosensitizers (PS) in Photodynamic therapy (PDT) is, the cause of side-effects to normal tissue due to dark toxicity. The usefulness of photosensitizers can be made possible by reducing its dark toxicity nature. In such scenario, biocompatible carriers can be used as a drug delivery system to evade the problems that arises while using free (dark toxic) drugs. So in this study, we have developed a nano drug delivery system called Phloroglucinol Succinic acid (PGSA) dendrimer, entrapped a photosensitizer, protoporphyrin IX (PpIX) inside the system and investigated whether the photodynamic efficacy of the anionic surface charged dendrimer-PpIX nano formulation is enhanced than achieved by the free PpIX in HeLa cancer cell lines. Moreover, the Reactive oxygen species (ROS) production was monitored using 2‧,7‧-dichlorodihydrofluorescein diacetate (H2DCF-DA)- ROS Marker with phase contrast microscopy for the IC50 values of free and dendrimer-PpIX nano formulation. Similarly, the mode of cell death has been confirmed by cell cycle analysis for the same. For the in vitro PDT application, we have used a simple light source (Light Emitting Diode) with a power of 30-50 mW for 20 min irradiation. Hence, in this study we have taken steps to report this anionic drug delivery system is good to consider for the photodynamic therapy applications with the photosensitizer, PpIX which satisfied the prime requirement of PDT.

Endoscopic and Photodynamic Therapy of Cholangiocarcinoma.

PubMed

Meier, Benjamin; Caca, Karel

2016-12-01

Most patients with cholangiocarcinoma (CCA) have unresectable disease. Endoscopic bile duct drainage is one of the major objectives of palliation of obstructive jaundice. Stent implantation using endoscopic retrograde cholangiography is considered to be the standard technique. Unilateral versus bilateral stenting is associated with different advantages and disadvantages; however, a standard approach is still not defined. As there are various kinds of stents, there is an ongoing discussion on which stent to use in which situation. Palliation of obstructive jaundice can be augmented through the use of photodynamic therapy (PDT). Studies have shown a prolonged survival for the combinations of PDT and different stent applications as well as combinations of PDT and additional systemic chemotherapy. More well-designed studies are needed to better evaluate and standardize endoscopic treatment of unresectable CCA.

A supramolecular photosensitizer system based on the host-guest complexation between water-soluble pillar[6]arene and methylene blue for durable photodynamic therapy.

PubMed

Yang, Kui; Wen, Jia; Chao, Shuang; Liu, Jing; Yang, Ke; Pei, Yuxin; Pei, Zhichao

2018-06-05

A supramolecular photosensitizer system WP6-MB was synthesized based on water-soluble pillar[6]arene and the photosensitizer methylene blue (MB) via host-guest interaction. MB can complex with WP6 directly with a high complex constant without further modification. In particular, WP6-MB can reduce the dark toxicity of MB remarkably. Furthermore, it can efficiently overcome photobleaching and extend the time for singlet oxygen production of MB upon light irradiation, which is significant for durable photodynamic therapy.

Somatostatin Analogues for Receptor Targeted Photodynamic Therapy

PubMed Central

Kaščáková, Slávka; Hofland, Leo J.; De Bruijn, Henriette S.; Ye, Yunpeng; Achilefu, Samuel; van der Wansem, Katy; van der Ploeg-van den Heuvel, Angelique; van Koetsveld, Peter M.; Brugts, Michael P.; van der Lelij, Aart-Jan; Sterenborg, Henricus J. C. M.; ten Hagen, Timo L. M.; Robinson, Dominic J.; van Hagen, Martin P.

2014-01-01

Photodynamic therapy (PDT) is an established treatment modality, used mainly for anticancer therapy that relies on the interaction of photosensitizer, light and oxygen. For the treatment of pathologies in certain anatomical sites, improved targeting of the photosensitizer is necessary to prevent damage to healthy tissue. We report on a novel dual approach of targeted PDT (vascular and cellular targeting) utilizing the expression of neuropeptide somatostatin receptor (sst2) on tumor and neovascular-endothelial cells. We synthesized two conjugates containing the somatostatin analogue [Tyr3]-octreotate and Chlorin e6 (Ce6): Ce6-K3-[Tyr3]-octreotate (1) and Ce6-[Tyr3]-octreotate-K3-[Tyr3]-octreotate (2). Investigation of the uptake and photodynamic activity of conjugates in-vitro in human erythroleukemic K562 cells showed that conjugation of [Tyr3]-octreotate with Ce6 in conjugate 1 enhances uptake (by a factor 2) in cells over-expressing sst2 compared to wild-type cells. Co-treatment with excess free Octreotide abrogated the phototoxicity of conjugate 1 indicative of a specific sst2-mediated effect. In contrast conjugate 2 showed no receptor-mediated effect due to its high hydrophobicity. When compared with un-conjugated Ce6, the PDT activity of conjugate 1 was lower. However, it showed higher photostability which may compensate for its lower phototoxicity. Intra-vital fluorescence pharmacokinetic studies of conjugate 1 in rat skin-fold observation chambers transplanted with sst2 + AR42J acinar pancreas tumors showed significantly different uptake profiles compared to free Ce6. Co-treatment with free Octreotide significantly reduced conjugate uptake in tumor tissue (by a factor 4) as well as in the chamber neo-vasculature. These results show that conjugate 1 might have potential as an in-vivo sst2 targeting photosensitizer conjugate. PMID:25111655

Micro-Encapsulated Porphyrins and Phthalocyanines - New Formulations in Photodynamic Therapy

NASA Astrophysics Data System (ADS)

Ion, R. M.

2017-06-01

Photodynamic therapy (PDT), as an innovative method for cancer tretament is based on a concerted action of some drugs, called sensitizers, which generate reactive oxygen species via a photochemical mechanism, leading to cellular necrosis or apoptosis. The present work aims at loading some sensitizers, as porphyrins (P) and phthalocyanines (Pc) into alginate particles. Particles were prepared by dropping alginate into an aqueous solution containing P or Pc and CaCl2, which allows the formation of particles through ionic crosslinking. It was obtained P or Pc loaded alginate beads with an average diameter of about 100 μm. For these systems, this paper analyses the spectroscopic properties, encapsulation into microcapsules, controlled releasing action and their photosensitizer capacity (singlet oxygen generation).

The apoptosis induced by HMME-based photodynamic therapy in rabbit vascular smooth muscle cells

NASA Astrophysics Data System (ADS)

Yin, Huijuan; Li, Xiaoyuan; Lin, Hong; Liu, Jianzhong; Yu, Hongkui

2007-02-01

Objective To study the effects of HMME-based photodynamic therapy on proliferation and apoptosis of rabbit vascular smooth muscle cells(VSMCs). Method The cytotoxic effect of HMME-PDT on rabbit vascular smooth muscle cells was studied by means of Trypan Blue assay, HMME at 10μg/ml concentration and the light dose at 2.4~4.8 J/cm2 were selected in the studies. The morphological character 24h post-PDT was investigated by HE Staining. Annexin V and propidium iodide (PI) binding assays were performed to analyze the characteristics of cell death after HMME-PDT. Furthermore, The intracellular distributions of the HMME were measured by the confocal laser scanning microscope. Result It was showed the photocytotoxity to VSMC cells was dose related by Trypan Blue assay. Histology observing suggests HMME-PDT could induce cell death through apoptosis or necrosis, and the apoptosic rate was up to 50.5% by AnnexinV /PI assay. Moreover, the fluorescence images of HMME intracellular localization demonstrated that the HMME diffused into the mitochondria. Conclusion HMME-PDT could significantly inhibite VSMC proliferation and induce apoptosis.

Feasibility of Raman spectroscopy in vitro after 5-ALA-based fluorescence diagnosis in the bladder

NASA Astrophysics Data System (ADS)

Grimbergen, M. C. M.; van Swol, C. F. P.; van Moorselaar, R. J. A.; Mahadevan-Jansen, A.,; Stone, N.

2006-02-01

Photodynamic diagnosis (PDD) has become popular in bladder cancer detection. Several studies have however shown an increased false positive biopsies rate under PDD guidance compared to conventional cystoscopy. Raman spectroscopy is an optical technique that utilizes molecular specific, inelastic scattering of light photons to interrogate biological tissues, which can successfully differentiate epithelial neoplasia from normal tissue and inflammations in vitro. This investigation was performed to show the feasibility of NIR Raman spectroscopy in vitro on biopsies obtained under guidance of 5-ALA induced PPIX fluorescence imaging. Raman spectra of a PPIX solution was measured to obtain a characteristic signature for the photosensitzer without contributions from tissue constituents. Biopsies were obtained from patients with known bladder cancer instilled with 50ml, 5mg 5-ALA two hours prior to trans-urethral resection of tumor (TURT). Additional biopsies were obtained at a fluorescent and non-fluorescent area, snap-frozen in liquid nitrogen and stored at -80 °C. Each biopsy was thawed before measurements (10sec integration time) with a confocal Raman system (Renishaw Gloucestershire, UK). The 830 nm excitation (300mW) source is focused on the tissue by a 20X ultra-long-working-distance objective. Differences in fluorescence background between the two groups were removed by means of a special developed fluorescence subtraction algorithm. Raman spectra from ALA biopsies showed different fluorescence background which can be effectively removed by a fluorescence subtraction algorithm. This investigation shows that the interaction of the ALA induced PPIX with Raman spectroscopy in bladder samples. Combination of these techniques in-vivo may lead to a viable method of optical biopsies in bladder cancer detection.

In vivo 808 nm image-guided photodynamic therapy based on an upconversion theranostic nanoplatform.

PubMed

Liu, Xiaomin; Que, Ivo; Kong, Xianggui; Zhang, Youlin; Tu, Langping; Chang, Yulei; Wang, Tong Tong; Chan, Alan; Löwik, Clemens W G M; Zhang, Hong

2015-09-28

A new strategy for efficient in vivo image-guided photodynamic therapy (PDT) has been demonstrated utilizing a ligand-exchange constructed upconversion-C60 nanophotosensitizer. This theranostic platform is superior to the currently reported nanophotosensitizers in (i) directly bonding photosensitizer C60 to the surface of upconversion nanoparticles (UCNPs) by a smart ligand-exchange strategy, which greatly shortened the energy transfer distance and enhanced the (1)O2 production, resulting in the improvement of the therapeutic effect; (ii) realizing in vivo NIR 808 nm image-guided PDT with both excitation (980 nm) and emission (808 nm) light falling in the biological window of tissues, which minimized auto-fluorescence, reduced light scatting and improved the imaging contrast and depth, and thus guaranteed noninvasive diagnostic accuracy. In vivo and ex vivo tests demonstrated its favorable bio-distribution, tumor-selectivity and high therapeutic efficacy. Owing to the effective ligand exchange strategy and the excellent intrinsic photophysical properties of C60, (1)O2 production yield was improved, suggesting that a low 980 nm irradiation dosage (351 J cm(-2)) and a short treatment time (15 min) were sufficient to perform NIR (980 nm) to NIR (808 nm) image-guided PDT. Our work enriches the understanding of UCNP-based PDT nanophotosensitizers and highlights their potential use in future NIR image-guided noninvasive deep cancer therapy.

The cost-utility of photodynamic therapy in eyes with neovascular macular degeneration--a value-based reappraisal with 5-year data.

PubMed

Brown, Gary C; Brown, Melissa M; Campanella, Joseph; Beauchamp, George R

2005-10-01

To assess the value conferred by photodynamic therapy (PDT) and the cost-utility of PDT for the treatment of classic, subfoveal choroidal neovascularization associated with age-related macular degeneration (ARMD). Average cost-utility analysis utilizing clinical trial data, patient-based time tradeoff utility preferences, and a third party insurer cost perspective. Five-year visual acuity data from the TAP (Treatment of Age-related Macular Degeneration With Photodynamic Therapy) Investigation were modeled into a 12-year, value-based, reference case, cost-utility model utilizing year 2004 Medicare costs and an outcome of dollar/QALY (dollars/quality-adjusted life-year). Discounting of outcomes and costs using net present value analysis with a 3% annual rate was performed as recommended by the Panel for Cost-Effectiveness in Health and Medicine. PDT with verteporfin (Visudyne) dye for classic subfoveal choroidal neovascularization confers an 8.1% quality of life (value) improvement over the 12-year life expectancy of the reference case, while during the last 8 years the value improvement is 9.5%. The average cost-utility of the intervention is dollar 31,103/QALY (quality-adjusted life-year). Extensive one-way sensitivity analysis values range from dollar 20,736/QALY if treatment efficacy is increased by 50% to dollar 62,207 if treatment efficacy is decreased by 50%, indicating robustness of the model. PDT using verteporfin dye to treat classic subfoveal choroidal neovascularization is a very cost-effective treatment by conventional standards. The marked improvement in cost-effectiveness compared with a previous report results from the facts that the treatment benefit increasingly accrues during 5 years of follow-up while the number of yearly treatments diminishes markedly during that time.

Can nanotechnology potentiate photodynamic therapy?

PubMed Central

Huang, Ying-Ying; Sharma, Sulbha K.; Dai, Tianhong; Chung, Hoon; Yaroslavsky, Anastasia; Garcia-Diaz, Maria; Chang, Julie; Chiang, Long Y.

2015-01-01

Photodynamic therapy (PDT) uses the combination of non-toxic dyes and harmless visible light to produce reactive oxygen species that can kill cancer cells and infectious microorganisms. Due to the tendency of most photosensitizers (PS) to be poorly soluble and to form nonphotoactive aggregates, drug-delivery vehicles have become of high importance. The nanotechnology revolution has provided many examples of nanoscale drug-delivery platforms that have been applied to PDT. These include liposomes, lipoplexes, nanoemulsions, micelles, polymer nanoparticles (degradable and nondegradable), and silica nanoparticles. In some cases (fullerenes and quantum dots), the actual nanoparticle itself is the PS. Targeting ligands such as antibodies and peptides can be used to increase specificity. Gold and silver nanoparticles can provide plasmonic enhancement of PDT. Two-photon excitation or optical upconversion can be used instead of one-photon excitation to increase tissue penetration at longer wavelengths. Finally, after sections on in vivo studies and nanotoxicology, we attempt to answer the title question, “can nano-technology potentiate PDT?” PMID:26361572

Results of photodynamic therapy in the combined treatment of choroidal metastasis

NASA Astrophysics Data System (ADS)

Likhvantseva, Vera G.; Osipova, Ekaterina V.; Petrenko, Mikhail V.; Merzlyakova, Oksana Y.; Kuzmin, Sergey G.; Vorozhtsov, Georgy N.

2007-07-01

Choroidal metastasis (CM) are more and more spreading type of eye's neoplasma. The frequency of CM is increasing with prolonging of cancer patients' life. And it makes worse the quality of their life because blindness. Photodynamic therapy (PDT) is very delicate modality, which can be used for this purpose. The aim of this work was to open the possibility and to determine the efficacy of photodynamic therapy (PDT) in the treatment of patients with CM. PDT was performed simultaneously with standard chemotherapy in 8 oncological patients with CM. We used photosensitizer Photosens in doses of 0.3 mg/kg and light doses 150 J/cm2 (675 nm). PDT was performed in the some stances. Its are ranged from 7 to 10. Complete tumor regression was achieved in 6 cases. The high retina ablation was developed in one case. And in one case effect was not complete: tumor size reduced from 5 mm to 3 mm of thickness. We didn't notice any recurrence for 6-18 months follow-up. PDT is modality that could to be used in the in the combined treatment of the CM.

Predictive model for photodynamic therapy with gold nanoparticles as vehicle for the photosensitizer delivery

NASA Astrophysics Data System (ADS)

Salas-García, I.; Fanjul-Vélez, F.; Ortega-Quijano, N.; Arce-Diego, J. L.

2013-06-01

Photodynamic Therapy offers multiple advantages to treat nonmelanoma skin cancer compared to conventional treatment techniques such as surgery, radiotherapy or chemotherapy. Among these advantages are particularly relevant its noninvasive nature, the use of non ionizing radiation and its high selectivity. However the therapeutic efficiency of the current clinical protocol is not complete in all the patients and depends on the type of pathology. Emerging strategies to overcome its current shortcomings include the use of nanostructures that can act as carriers for conventional photosensitizers and improve the treatment selectivity and provide a controlled release of the photoactive agent. In this work, a model for photodynamic therapy combined with gold nanocarriers for a photosensitizer commonly used in dermatology is presented and applied to a basal cell carcinoma in order to predict the cytotoxic agent spatial and temporal evolution.

Structural and functional imaging for vascular targeted photodynamic therapy

NASA Astrophysics Data System (ADS)

Li, Buhong; Gu, Ying; Wilson, Brian C.

2017-02-01

Vascular targeted photodynamic therapy (V-PDT) has been widely used for the prevention or treatment of vascular-related diseases, such as localized prostate cancer, wet age-related macular degeneration, port wine stains, esophageal varices and bleeding gastrointestinal mucosal lesions. In this study, the fundamental mechanisms of vascular responses during and after V-PDT will be introduced. Based on the V-PDT treatment of blood vessels in dorsal skinfold window chamber model, the structural and functional imaging, which including white light microscopy, laser speckle imaging, singlet oxygen luminescence imaging, and fluorescence imaging for evaluating vascular damage will be presented, respectively. The results indicate that vessel constriction and blood flow dynamics could be considered as the crucial biomarkers for quantitative evaluation of vascular damage. In addition, future perspectives of non-invasive optical imaging for evaluating vascular damage of V-PDT will be discussed.

Photodynamic therapy with topical photosensitizers in mucosal and semimucosal areas: review from a dermatologic perspective.

PubMed

Grandi, Vieri; Sessa, Maurizio; Pisano, Luigi; Rossi, Riccardo; Galvan, Arturo; Gattai, Riccardo; Mori, Moira; Tiradritti, Luana; Bacci, Stefano; Zuccati, Giuliano; Cappugi, Pietro; Pimpinelli, Nicola

2018-04-15

Photodynamic Therapy is a procedure based on the interaction between a Photo Sensitizer, a light source with a specific wavelength and oxygen. Aim of this Review is to provide a brief and updated analysis of scientific reports of the use of PDT with topical PS in the management of oncological, infectious, and inflammatory disorders involving mucosal and semimucosal areas, with a specific focus on diseases of dermatologic interest. Copyright © 2018. Published by Elsevier B.V.

CT contrast predicts pancreatic cancer treatment response to verteporfin-based photodynamic therapy

NASA Astrophysics Data System (ADS)

Jermyn, Michael; Davis, Scott C.; Dehghani, Hamid; Huggett, Matthew T.; Hasan, Tayyaba; Pereira, Stephen P.; Bown, Stephen G.; Pogue, Brian W.

2014-04-01

The goal of this study was to determine dominant factors affecting treatment response in pancreatic cancer photodynamic therapy (PDT), based on clinically available information in the VERTPAC-01 trial. This trial investigated the safety and efficacy of verteporfin PDT in 15 patients with locally advanced pancreatic adenocarcinoma. CT scans before and after contrast enhancement from the 15 patients in the VERTPAC-01 trial were used to determine venous-phase blood contrast enhancement and this was correlated with necrotic volume determined from post-treatment CT scans, along with estimation of optical absorption in the pancreas for use in light modeling of the PDT treatment. Energy threshold contours yielded estimates for necrotic volume based on this light modeling. Both contrast-derived venous blood content and necrotic volume from light modeling yielded strong correlations with observed necrotic volume (R2 = 0.85 and 0.91, respectively). These correlations were much stronger than those obtained by correlating energy delivered versus necrotic volume in the VERTPAC-01 study and in retrospective analysis from a prior clinical study. This demonstrates that contrast CT can provide key surrogate dosimetry information to assess treatment response. It also implies that light attenuation is likely the dominant factor in the VERTPAC treatment response, as opposed to other factors such as drug distribution. This study is the first to show that contrast CT provides needed surrogate dosimetry information to predict treatment response in a manner which uses standard-of-care clinical images, rather than invasive dosimetry methods.

Photodynamic therapy as a novel treatment for halitosis in adolescents: study protocol for a randomized controlled trial.

PubMed

Lopes, Rubia Garcia; de Godoy, Camila Haddad Leal; Deana, Alessandro Melo; de Santi, Maria Eugenia Simões Onofre; Prates, Renato Araujo; França, Cristiane Miranda; Fernandes, Kristianne Porta Santos; Mesquita-Ferrari, Raquel Agnelli; Bussadori, Sandra Kalil

2014-11-14

Halitosis is a common problem that affects a large portion of the population worldwide. The origin of this condition is oral in 90% and systemic in 10% of cases. The unpleasant odor is mainly the result of volatile sulfur compounds produced by Gram-negative bacteria. However, it has recently been found that anaerobic Gram-positive bacteria also produce hydrogen sulfide (H2S) in the presence of amino acids, such as cysteine. Light, both with and without the use of chemical agents, has been used to induce therapeutic and antimicrobial effects. In photodynamic therapy, the antimicrobial effect is confined to areas covered by photosensitizing dye. The aim of the present study is to evaluate the antimicrobial effect of photodynamic therapy on halitosis in adolescents through the analysis of volatile sulfur compounds measured using gas chromatography and microbiological analysis of coated tongue. A quantitative clinical trial will be carried out involving 60 adolescents randomly divided into the following groups: group 1 will receive treatment with a tongue scraper, group 2 will receive photodynamic therapy applied to the posterior two-thirds of the dorsum of the tongue, and group 3 will receive combined treatment (tongue scraper and photodynamic therapy). Gas chromatography (OralChromaTM) and microbiological analysis will be used for the diagnosis of halitosis at the beginning of the study. Post-treatment evaluations will be conducted at one hour and 24 hours after treatment. The statistical analysis will include the Shapiro-Wilk test for the determination of the distribution of the data. If normal distribution is demonstrated, analysis of variance followed by Tukey's test will be used to compare groups. The Kruskal-Wallis test followed by the Student-Newman-Keuls test will be used for data with non-normal distribution. Either the paired t-test or the Wilcoxon test will be used to compare data before and after treatment, depending on the distribution of the data. The

Engineering a Cell-surface Aptamer Circuit for Targeted and Amplified Photodynamic Cancer Therapy

PubMed Central

Han, Da; Zhu, Guizhi; Wu, Cuichen; Zhu, Zhi; Chen, Tao; Zhang, Xiaobing

2013-01-01

Photodynamic therapy (PDT) is one of the most promising and noninvasive methods for clinical treatment of different malignant diseases. Here, we present a novel strategy of designing an aptamer-based DNA nanocircuit capable of the selective recognition of cancer cells, controllable activation of photosensitizer and amplification of photodynamic therapeutic effect. The aptamers can selectively recognize target cancer cells and bind to the specific proteins on cell membranes. Then the overhanging catalyst sequence on aptamer can trigger a toehold-mediated catalytic strand displacement to activate photosensitizer and achieve amplified therapeutic effect. The specific binding-induced activation allows the DNA circuit to distinguish diseased cells from healthy cells, reducing damage to nearby healthy cells. Moreover, the catalytic amplification reaction will only take place close to the target cancer cells, resulting in a high local concentration of singlet oxygen to selectively kill the target cells. The principle employed in this study demonstrated the feasibility of assembling a DNA circuit on cell membranes and could further broaden the utility of DNA circuits for applications in biology, biotechnology, and biomedicine. PMID:23397942

Photodynamic therapy in dermatology: past, present, and future

NASA Astrophysics Data System (ADS)

Darlenski, Razvigor; Fluhr, Joachim W.

2013-06-01

Photodynamic therapy (PDT) is a noninvasive therapeutic method first introduced in the field of dermatology. It is mainly used for the treatment of precancerous and superficial malignant skin tumors. Today PDT finds new applications not only for nononcologic dermatoses but also in the field of other medical specialties such as otorhinolaryngology, ophthalmology, neurology, gastroenterology, and urology. We are witnessing a broadening of the spectrum of skin diseases that are treated by PDT. Since its introduction, PDT protocol has evolved significantly in terms of increasing method efficacy and patient safety. In this era of evidence-based medicine, it is expected that much effort will be put into creating a worldwide accepted consensus on PDT. A review on the current knowledge of PDT is given, and the historical basis of the method's evolution since its introduction in the 1900s is presented. At the end, future challenges of PDT are focused on discussing gaps that exist for research in the field.

Macrophage-directed immunotherapy as adjuvant to photodynamic therapy of cancer.

PubMed

Korbelik, M; Naraparaju, V R; Yamamoto, N

1997-01-01

The effect of Photofrin-based photodynamic therapy (PDT) and adjuvant treatment with serum vitamin D3-binding protein-derived macrophage-activating factor (DBPMAF) was examined using a mouse SCCVII tumour model (squamous cell carcinoma). The results show that DBPMAF can markedly enhance the curative effect of PDT. The most effective DBPMAF therapy consisted of a combination of intraperitoneal and peritumoral injections (50 and 0.5 ng kg-1 respectively) administered on days 0, 4, 8 and 12 after PDT. Used with a PDT treatment curative to 25% of the treated tumours, this DBPMAF regimen boosted the cures to 100%. The DBPMAF therapy alone showed no notable effect on the growth of SCCVII tumour. The PDT-induced immunosuppression, assessed by the evaluation of delayed-type contact hypersensitivity response in treated mice, was greatly reduced with the combined DBPMAF treatment. These observations suggest that the activation of macrophages in PDT-treated mice by adjuvant immunotherapy has a synergistic effect on tumour cures. As PDT not only reduces tumour burden but also induces inflammation, it is proposed that recruitment of the activated macrophages to the inflamed tumour lesions is the major factor for the complete eradication of tumours.

Macrophage-directed immunotherapy as adjuvant to photodynamic therapy of cancer.

PubMed Central

Korbelik, M.; Naraparaju, V. R.; Yamamoto, N.

1997-01-01

The effect of Photofrin-based photodynamic therapy (PDT) and adjuvant treatment with serum vitamin D3-binding protein-derived macrophage-activating factor (DBPMAF) was examined using a mouse SCCVII tumour model (squamous cell carcinoma). The results show that DBPMAF can markedly enhance the curative effect of PDT. The most effective DBPMAF therapy consisted of a combination of intraperitoneal and peritumoral injections (50 and 0.5 ng kg-1 respectively) administered on days 0, 4, 8 and 12 after PDT. Used with a PDT treatment curative to 25% of the treated tumours, this DBPMAF regimen boosted the cures to 100%. The DBPMAF therapy alone showed no notable effect on the growth of SCCVII tumour. The PDT-induced immunosuppression, assessed by the evaluation of delayed-type contact hypersensitivity response in treated mice, was greatly reduced with the combined DBPMAF treatment. These observations suggest that the activation of macrophages in PDT-treated mice by adjuvant immunotherapy has a synergistic effect on tumour cures. As PDT not only reduces tumour burden but also induces inflammation, it is proposed that recruitment of the activated macrophages to the inflamed tumour lesions is the major factor for the complete eradication of tumours. PMID:9010027

Preparation of fluorescent mesoporous hollow silica-fullerene nanoparticles via selective etching for combined chemotherapy and photodynamic therapy

NASA Astrophysics Data System (ADS)

Yang, Yannan; Yu, Meihua; Song, Hao; Wang, Yue; Yu, Chengzhong

2015-07-01

Well-dispersed mesoporous hollow silica-fullerene nanoparticles with particle sizes of ~50 nm have been successfully prepared by incorporating fullerene molecules into the silica framework followed by a selective etching method. The fabricated fluorescent silica-fullerene composite with high porosity demonstrates excellent performance in combined chemo/photodynamic therapy.Well-dispersed mesoporous hollow silica-fullerene nanoparticles with particle sizes of ~50 nm have been successfully prepared by incorporating fullerene molecules into the silica framework followed by a selective etching method. The fabricated fluorescent silica-fullerene composite with high porosity demonstrates excellent performance in combined chemo/photodynamic therapy. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02769a

Fluorescence Imaging Assisted Photodynamic Therapy Using Photosensitizer-Linked Gold Quantum Clusters.

PubMed

Nair, Lakshmi V; Nazeer, Shaiju S; Jayasree, Ramapurath S; Ajayaghosh, Ayyappanpillai

2015-06-23

Fluorescence imaging assisted photodynamic therapy (PDT) is a viable two-in-one clinical tool for cancer treatment and follow-up. While the surface plasmon effect of gold nanorods and nanoparticles has been effective for cancer therapy, their emission properties when compared to gold nanoclusters are weak for fluorescence imaging guided PDT. In order to address the above issues, we have synthesized a near-infrared-emitting gold quantum cluster capped with lipoic acid (L-AuC with (Au)18(L)14) based nanoplatform with excellent tumor reduction property by incorporating a tumor-targeting agent (folic acid) and a photosensitizer (protoporphyrin IX), for selective PDT. The synthesized quantum cluster based photosensitizer PFL-AuC showed 80% triplet quantum yield when compared to that of the photosensitizer alone (63%). PFL-AuC having 60 μg (0.136 mM) of protoporphyrin IX was sufficient to kill 50% of the tumor cell population. Effective destruction of tumor cells was evident from the histopathology and fluorescence imaging, which confirm the in vivo PDT efficacy of PFL-AuC.

Positive response of a recurrent keloid scar to topical methyl aminolevulinate-photodynamic therapy.

PubMed

Nie, Zhuxiang; Bayat, Ardeshir; Behzad, Farhad; Rhodes, Lesley E

2010-12-01

A 36-year-old Caucasian female of Iranian origin presented with a persistently raised dermal lesion under her chin, confirmed histologically to be a keloid scar. There was a 4-year history of a negative response to a range of conventional treatments including topical silicone gel sheets, steroid creams, steroid injections and surgical excision. In view of treatment failure and an in vitro study indicating a positive effect of photodynamic therapy (PDT)on keloid fibroblasts, we treated our patient's lesion with five sessions of methyl aminolevulinate photodynamic therapy (MAL-PDT) over a period of 5 months. Following this treatment regime, her keloid scar had considerably reduced in size and become flattened.The surface of the keloid also became smooth, with attenuation in erythema at the margin as well as an improvement in the colour of the scar, which was better matched to the surrounding skin. There was no recurrence at 1-year follow-up and this treatment resulted in an overall acceptable cosmetic outcome. This case report presents PDT as a potential treatment option for persistent keloid lesions unresponsive to conventional scar modulation therapies and suggests a need for further research in this area.

Endoscopic and Photodynamic Therapy of Cholangiocarcinoma

PubMed Central

Meier, Benjamin; Caca, Karel

2016-01-01

Background Most patients with cholangiocarcinoma (CCA) have unresectable disease. Endoscopic bile duct drainage is one of the major objectives of palliation of obstructive jaundice. Methods/Results Stent implantation using endoscopic retrograde cholangiography is considered to be the standard technique. Unilateral versus bilateral stenting is associated with different advantages and disadvantages; however, a standard approach is still not defined. As there are various kinds of stents, there is an ongoing discussion on which stent to use in which situation. Palliation of obstructive jaundice can be augmented through the use of photodynamic therapy (PDT). Studies have shown a prolonged survival for the combinations of PDT and different stent applications as well as combinations of PDT and additional systemic chemotherapy. Conclusion More well-designed studies are needed to better evaluate and standardize endoscopic treatment of unresectable CCA. PMID:28229075

Initiation of Autophagy by Photodynamic Therapy

PubMed Central

Kessel, David; Oleinick, Nancy L.

2010-01-01

Photodynamic therapy (PDT) involves the irradiation of photosensitized cells with light. Depending on localization of the photosensitizing agent, the process can induce photodamage to the endoplasmic reticulum (ER), mitochondria, plasma membrane, and/or lysosomes. When ER or mitochondria are targeted, antiapoptotic proteins of the Bcl-2 family are especially sensitive to photodamage. Both apoptosis and autophagy can occur after PDT, autophagy being associated with enhanced survival at low levels of photodamage to some cells. Autophagy can become a cell-death pathway if apoptosis is inhibited or when cells attempt to recycle damaged constituents beyond their capacity for recovery. While techniques associated with characterization of autophagy are generally applicable, PDT introduces additional factors related to unknown sites of photodamage that may alter autophagic pathways. This chapter discusses issues that may arise in assessing autophagy after cellular photodamage. PMID:19216899

Photodynamic therapy of locally advanced basal cell skin cancer

NASA Astrophysics Data System (ADS)

Riabov, Mikhail V.; Stranadko, Evgeny P.

2005-08-01

The treatment of locally spread basal-cell skin cancer is very difficult and often complicated with local recurrence. Traditional techniques are sometimes insufficient for this pathology, especially for recurrent tumors. In the State Research Center for Laser Medicine photodynamic therapy had been used for treatment of 103 patients with locally spread basal-cell skin cancer, including 64 with recurrent tumors. Therapeutic effect has been achieved in all cases, including complete tumor resorption in 67% of patients. Presented paper contains analysis of immediate and long-term follow-up results.

Potentiation of the photodynamic action of hypericin.

PubMed

Saw, Constance Lay Lay; Heng, Paul Wan Sia; Olivo, Malini

2008-01-01

Hypericin (HY) is an interesting photosensitizer with dark activity and photodynamic therapy (PDT) effects via p53-independent pathway. In photodynamic diagnosis (PDD) of bladder cancer using HY, very high sensitivity and specificity were reported, in comparison with its counterpart, 5-aminolevulinic acid (5-ALA). HY was tested for the detection of human gastric cancer. It was also studied for treating some cancers and age-related macular degeneration and showed some promising findings. Several strategies to enhance the efficacy of HY-PDD and HY-PDT are reviewed. Using fractionated light dosing, fractionated drug dosing, hyperthermia, adjuvants such as oxygen carrier/antiangiogenesis, chemical modifications, and formulation approaches to enhance the PDT effects of HY are topics of this review. Despite cutting-edge technology approach such as preparing transferring-mediated targeting HY liposomes and nanoparticles of HY, such preparations did not always offer the desired enhanced treatment effects. It turns out that simple solutions of HY, especially those prepared without using plasma protein, were more successful in enhancing the delivery of HY for in vitro and in vivo systems. Thus, the HY-PDT with these formulations performed better. It is anticipated that HY-PDD and HY-PDT can be enhanced and optimized with the right combination of light dosimetry and drug dose in an effective formulation containing a suitable adjuvant. Hyperoxygenation and hyperthermia can also be used to further enhance the efficacy of HY-PDT.

Impact of the PPAR-γ2 Pro12Ala Polymorphism and ACE Inhibitor Therapy on New-Onset Microalbuminuria in Type 2 Diabetes: Evidence From BENEDICT

PubMed Central

De Cosmo, Salvatore; Motterlini, Nicola; Prudente, Sabrina; Pellegrini, Fabio; Trevisan, Roberto; Bossi, Antonio; Remuzzi, Giuseppe; Trischitta, Vincenzo; Ruggenenti, Piero

2009-01-01

OBJECTIVE Cross-sectional studies found less microalbuminuria in type 2 diabetic patients with the Ala12 allele of the peroxisome proliferator–activated receptor-γ2 (PPAR-γ2) Pro12Ala polymorphism. We prospectively evaluated the association between Pro12Ala polymorphism (rs1801282) and new-onset microalbuminuria. RESEARCH DESIGN AND METHODS Pro12Ala polymorphism was genotyped by TaqMan-based assay in genomic DNA of 1,119 consenting patients from BErgamo NEphrologic DIabetic Complications Trial (BENEDICT)—a prospective, randomized trial evaluating ACE inhibition effect on new-onset microalbuminuria (albuminuria 20–200 μg/min in at least two of three consecutive overnight urine collections in two consecutive visits) in hypertensive type 2 diabetes with albuminuria <20 μg/min at inclusion. RESULTS Baseline characteristics of Ala (Ala/Ala or Ala/Pro) carriers and Pro/Pro homozygotes were similar, with a nonsignificant trend to lower albuminuria (P = 0.1107) in the 177 Ala carriers. Over a median (interquartile range) of 44.0 (17.1–51.9) months, 7 (4%) Ala carriers and 86 (9.1%) Pro/Pro homozygotes developed microalbuminuria (hazard ratio [HR] 0.45 [95% CI 0.21–0.97]; P = 0.042). Final albuminuria was significantly lower in Ala carriers than Pro/Pro homozygotes (7.3 ± 9.1 vs. 10.5 ± 24.9 μg/min, respectively), even after adjustment for baseline albuminuria (P = 0.048). Baseline and follow-up blood pressure and metabolic control were similar in both groups. Incidence of microalbuminuria was significantly decreased by ACE versus non-ACE inhibitor therapy in Pro/Pro homozygotes (6.3 vs. 11.9%, respectively, HR 0.46 [0.29–0.72]; P < 0.001). CONCLUSIONS In type 2 diabetes, the Ala allele protects from worsening albuminuria and new-onset microalbuminuria, and ACE inhibition blunts the excess risk of microalbuminuria associated with the Pro/Pro genotype. Evaluating Pro12Ala polymorphism may help identifying patients at risk who may benefit the most from

Photodynamic Effect of Ni Nanotubes on an HeLa Cell Line

PubMed Central

Hammad Aziz, Muhammad; Fakhar-e-Alam, M.; Fatima, Mahvish; Shaheen, Fozia; Iqbal, Seemab; Atif, M.; Talha, Muhammad; Mansoor Ali, Syed; Afzal, Muhammad; Majid, Abdul; Shelih Al.Harbi, Thamir; Ismail, Muhammad; Wang, Zhiming M.; AlSalhi, M. S.; Alahmed, Z. A.

2016-01-01

Nickel nanomaterials are promising in the biomedical field, especially in cancer diagnostics and targeted therapy, due to their distinctive chemical and physical properties. In this experiment, the toxicity of nickel nanotubes (Ni NTs) were tested in an in vitro cervical cancer model (HeLa cell line) to optimize the parameters of photodynamic therapy (PDT) for their greatest effectiveness. Ni NTs were synthesized by electrodeposition. Morphological analysis and magnetic behavior were examined using a Scanning electron microscope (SEM), an energy dispersive X-ray analysis (EDAX) and a vibrating sample magnetometer (VSM) analysis. Phototoxic and cytotoxic effects of nanomaterials were studied using the Ni NTs alone as well as in conjugation with aminolevulinic acid (5-ALA); this was performed both in the dark and under laser exposure. Toxic effects on the HeLa cell model were evaluated by a neutral red assay (NRA) and by detection of intracellular reactive oxygen species (ROS) production. Furthermore, 10–200 nM of Ni NTs was prepared in solution form and applied to HeLa cells in 96-well plates. Maximum toxicity of Ni NTs complexed with 5-ALA was observed at 100 J/cm2 and 200 nM. Up to 65–68% loss in cell viability was observed. Statistical analysis was performed on the experimental results to confirm the worth and clarity of results, with p-values = 0.003 and 0.000, respectively. Current results pave the way for a more rational strategy to overcome the problem of drug bioavailability in nanoparticulate targeted cancer therapy, which plays a dynamic role in clinical practice. PMID:26990435

Photodynamic therapy on the normal rabbit larynx with phthalocyanine and 5-aminolaevulinic acid induced protoporphyrin IX photosensitisation.

PubMed Central

Kleemann, D.; MacRobert, A. J.; Mentzel, T.; Speight, P. M.; Bown, S. G.

1996-01-01

Photodynamic therapy (PDT) is a promising technique for the treatment of small tumours in organs where it is essential to minimise damage to immediately adjacent normal tissue as PDT damage to many tissues heals by regeneration rather than scarring. As preservation of function is one of the main aims of treating laryngeal tumours, this project studied the effects of PDT on the normal rabbit larynx with two photosensitisers, endogenous protoporphyrin IX (PPIX) induced by the administration of 5-aminolaevulinic acid (ALA) and disulphonated aluminium phthalocyanine (AIS2Pc). The main aims of the study were to examine the distribution of protoporphyrin IX and AIS2Pc by fluorescence microscopy in the different regions of the larnyx and to assess the nature and subsequent healing of PDT damage. Peak levels of PPIX were found 0.5-4 h after administration of ALA (depending on dose) with highest levels in the epithelium of the mucosa. With 100 mg kg-1, PDT necrosis was limited to the mucosa, whereas with 200 mg kg-1 necrosis extended to the muscle. With 1 mg kg-1 AIS2Pc, 1 h after administration, the drug was mainly in the submucosa and muscle, whereas after 24 h, it was predominantly in the mucosa. PDT at 1 h caused deep necrosis whereas at 24 h it was limited to the mucosa. All mucosal necrosis healed by regeneration whereas deeper effects left some fibrosis. No damage to cartilage was seen in any of the animals studied. The results of this study have shown that both photosensitisers are suitable for treating mucosal lesions of the larynx, but that for both it is important to optimise the drug dose and time interval between drug and light to avoid unacceptable changes in normal areas. Images Figure 2 Figure 3 Figure 5 Figure 6 Figure 7 Figure 8 PMID:8679457

Optical and photoacoustic dual-modality imaging guided synergistic photodynamic/photothermal therapies

NASA Astrophysics Data System (ADS)

Yan, Xuefeng; Hu, Hao; Lin, Jing; Jin, Albert J.; Niu, Gang; Zhang, Shaoliang; Huang, Peng; Shen, Baozhong; Chen, Xiaoyuan

2015-01-01

Phototherapies such as photodynamic therapy (PDT) and photothermal therapy (PTT), due to their specific spatiotemporal selectivity and minimal invasiveness, have been widely investigated as alternative treatments of malignant diseases. Graphene and its derivatives not only have been used as carriers to deliver photosensitizers for PDT, but also as photothermal conversion agents (PTCAs) for PTT. Herein, we strategically designed and produced a novel photo-theranostic platform based on sinoporphyrin sodium (DVDMS) photosensitizer-loaded PEGylated graphene oxide (GO-PEG-DVDMS) for enhanced fluorescence/photoacoustic (PA) dual-modal imaging and combined PDT and PTT. The GO-PEG carrier drastically improves the fluorescence of loaded DVDMS via intramolecular charge transfer. Concurrently, DVDMS significantly enhances the near-infrared (NIR) absorption of GO for improved PA imaging and PTT. The cancer theranostic capability of the as-prepared GO-PEG-DVDMS was carefully investigated both in vitro and in vivo. This novel theranostics is well suited for fluorescence/PA dual-modal imaging and synergistic PDT/PTT.

Photodynamic therapy versus ultrasonic irrigation: interaction with endodontic microbial biofilm, an ex vivo study.

PubMed

Muhammad, Omid H; Chevalier, Marlene; Rocca, Jean-Paul; Brulat-Bouchard, Nathalie; Medioni, Etienne

2014-06-01

Photodynamic therapy was introduced as an adjuvant to conventional chemo-mechanical debridement during endodontic treatment to overcome the persistence of biofilms. The aim of this study was to evaluate the ability of photodynamic therapy (PDT) to disrupt an experimental microbial biofilm inside the root canal in a clinically applicable working time. Thirty extracted teeth were prepared and then divided in three groups. All samples were infected with an artificially formed biofilm made of Enterococcus faecalis, Streptococcus salivarius, Porphyromonas gingivalis and Prevotella intermedia bacteria. First group was treated with Aseptim Plus® photo-activated (LED) disinfection system, second group by a 650 nm Diode Laser and Toluidine blue as photosensitizer, and the third group, as control group, by ultrasonic irrigation (PUI) using EDTA 17% and NaOCl 2.6% solutions. The working time for all three groups was fixed at 3 min. Presence or absence of biofilm was assessed by aerobic and anaerobic cultures. There was no statistically significant difference between results obtained from groups treated by Aseptim Plus® and Diode Laser (P<0.6267). In cultures of both groups there was a maximal bacterial growth. The group that was treated by ultrasonic irrigation and NaOCl and EDTA solutions had the best results (P<0.0001): there was a statistically significant reduction of bacterial load and destruction of microbial biofilm. Under the condition of this study, Photodynamic therapy could not disrupt endodontic artificial microbial biofilm and could not inhibit bacterial growth in a clinically favorable working time. Copyright © 2014 Elsevier B.V. All rights reserved.

Intense pulse light and 5-ALA PDT: phototoxic effects in vitro depend on the spectral overlap with protoporphyrine IX but do not match cut-off filter notations.

PubMed

Maisch, Tim; Moor, Anne C E; Regensburger, Johannes; Ortland, Christoph; Szeimies, Rolf-Markus; Bäumler, Wolfgang

2011-02-01

Successful photodynamic therapy (PDT) requires a light source by which light is absorbed by the photosensitizer. Such absorption is achieved by adapting the emission spectrum of the lamp to the absorption-spectrum of the photosensitizer. Intense pulsed light sources (IPLs) are widely used in dermatology, but a standardized protocol for IPL-PDT is not available. Five different IPLs were chosen to evaluate their efficacy for PDT in vitro and the possibility for developing a standard protocol for PDT. Emission-spectra of IPLs were measured with an optical spectrograph and compared with the absorption spectrum of protoporphyrine IX (PpIX). Keratinocytes were incubated with 5-ALA and illuminated with the IPLs. Cell viability was determined for radiant exposures ranging from 0 to 504 J/cm(2) and pulse durations from 8 to 100 milliseconds. A standard LED light source was used as a reference. Cell viability is less effectively reduced by 5-ALA-PDT with IPLs than by a LED light source. Radiant exposures of the five IPLs ranged between 80 and 311 J/cm(2) to achieve the EC(50) value. This value correlated with the spectral overlap of the respective IPL and the absorption-spectrum of PpIX but not with the cut-off filter notations supplied by the manufacturer. All IPLs assessed emit different spectra because of different filter technologies. Different radiant exposures (J/cm(2) ) were necessary to achieve a photodynamic effect with 5-ALA in vitro depending on these spectra similar to the photodynamic effect of the standard LED light source. IPLs may be applicable in clinical PDT but radiant exposure protocols must be separately evaluated for each single IPL despite similar cut-off filter specifications. Such protocols are highly important for clinical practice to avoid a potential mismatch of excitation wavelengths and to prevent photothermal side effects when light intensities of up to hundreds of W/cm(2) are applied. Copyright © 2011 Wiley-Liss, Inc.

Photodynamic therapy of Cervical Intraepithelial Neoplasia (CIN) high grade

NASA Astrophysics Data System (ADS)

Carbinatto, Fernanda M.; Inada, Natalia M.; Lombardi, Welington; da Silva, Eduardo V.; Belotto, Renata; Kurachi, Cristina; Bagnato, Vanderlei S.

2016-02-01

Cervical intraepithelial neoplasia (CIN) is the precursor of invasive cervical cancer and associated with human papillomavirus (HPV) infection. Photodynamic therapy (PDT) is a technique that has been used for the treatment of tumors. PDT is based on the accumulation of a photosensitizer in target cells that will generate cytotoxic reactive oxygen species upon illumination, inducing the death of abnormal tissue and PDT with less damaging to normal tissues than surgery, radiation, or chemotherapy and seems to be a promising alternative procedure for CIN treatment. The CIN high grades (II and III) presents potential indications for PDT due the success of PDT for CIN low grade treatment. The patients with CIN high grade that were treated with new clinic protocol shows lesion regression to CIN low grade 60 days after the treatment. The new clinical protocol using for treatment of CIN high grade shows great potential to become a public health technique.

Functional manganese dioxide nanosheet for targeted photodynamic therapy and bioimaging in vitro and in vivo

NASA Astrophysics Data System (ADS)

Kim, Seongchan; Ahn, Seong Min; Lee, Ji-Seon; Kim, Tae Shik; Min, Dal-Hee

2017-06-01

Photodynamic therapy (PDT) has been widely studied as a promising non-invasive therapeutic strategy for the treatment of cancer. However, the poor solubility of photosensitizer (PS) in aqueous solution and inefficient cell-penetrating capability have limited the target-specific PDT. Herein, we develop a novel targeted photodynamic therapeutic and bioimaging system based on folic acid (FA)-conjugated MnO2 (FA-MnO2) nanosheet as a new carrier of PS, zinc phthalocyanine (ZnPc). ZnPc loaded FA-MnO2 nanosheet (FA-MnO2/ZnPc) complex is successfully formed by electrostatic interaction and coordination. We find that FA-MnO2/ZnPc complex exhibits excellent targeted delivery of ZnPc into folate receptor positive cancer cells and the ZnPc is released out from the complex via endogenous glutathione (GSH) stimulus, facilitating simultaneous bioimaging and targeted PDT by singlet oxygen (SO) generation upon light irradiation, showing high efficacy with only one tenth of conventional PS dosage in vitro and in vivo.

Current Concepts in Gastrointestinal Photodynamic Therapy

PubMed Central

Webber, John; Herman, Mark; Kessel, David; Fromm, David

1999-01-01

Objective To review current concepts of photodynamic therapy (PDT) applied to the treatment of tumors of the gastrointestinal tract. Summary Background Data PDT initially involves the uptake or production of a photosensitive compound by tumor cells. Subsequent activation of the photoreactive compound by a specific wavelength of light results in cell death, either directly or as a result of vascular compromise and/or apoptosis. Methods The authors selectively review current concepts relating to photosensitization, photoactivation, time of PDT application, tissue selectivity, sites of photodynamic action, PDT effects on normal tissue, limitations of PDT, toxicity of photosensitizers, application of principles of PDT to tumor detection, and current applications of PDT to tumors of the gastrointestinal tract. Results PDT is clearly effective for small cancers, but it is not yet clear in which cases such treatment is more effective than other currently acceptable approaches. The major side effect of PDT is cutaneous photosensitization. The major limitation of PDT is depth of tumor kill. As data from current and future clinical trials become available, a clearer perspective of where PDT fits in the treatment of cancers will be gained. Many issues regarding pharmacokinetic data of photosensitizers, newer technology involved in light sources, optimal treatment regimens that take advantage of the pharmacophysiology of photoablation, and light dosimetry still require solution. One can foresee application of differing sensitizers and light sources depending on the specific clinical situation. As technologic advances occur, interstitial PDT may have significant application. Conclusions PDT has a potentially important role either as a primary or adjuvant mode of treatment of tumors of the gastrointestinal tract. PMID:10400031

A laser unit for photodynamic therapy and robot-assisted microsurgery in dentistry

NASA Astrophysics Data System (ADS)

Chunikhin, A. A.; Bazikyan, E. A.; Pikhtin, N. A.

2017-06-01

Results are presented of photochemical experiments with an IR-laser unit for microsurgery and photodynamic therapy in dentistry. The efficiency of direct generation of singlet oxygen in model organic media in the continuous-wave and pulsed nanosecond modes is examined. The unit can serve both as an independent instrument and as a part of a complex for robot-assisted surgery and dentistry.

Mitochondria-targeting for improved photodynamic therapy

NASA Astrophysics Data System (ADS)

Ngen, Ethel J.

Photodynamic therapy (PDT) is an emerging cancer therapeutic modality, with great potential to selectively treat surface cancers, thus minimizing systemic side effects. In this dissertation, two approaches to deliver photosensitizers to mitochondria were investigated: 1) Reducing photosensitizer sizes to improve endocytosis and lysosomal localization. Upon irradiation the photosensitizers would then produce singlet oxygen which could rupture the lysosomal membrane releasing the lysosomally trapped photosensitizers to the cytosol, from where they could relocalize to mitochondria by passive diffusion (photochemical internalization). 2) Using delocalized lipophilic cationic dyes (DLCs) to exploit membrane potential differences between the cytoplasm and mitochondria in delivering photosensitizers to mitochondria. To investigate the effects of steric hindrance on mitochondrial localization and photodynamic response, a series of eight thiaporphyrins were studied. Two new thiaporphyrin analogues 6 and 8 with reduced steric hindrance at the 10- and 15- meso positions were studied in comparison to 5,20-diphenyl-10,15-bis[4 (carboxymethyleneoxy)-phenyl]-21,23-dithiaporphyrin 1, previously validated as a potential second generation photosensitizer. Although 6 showed an extraordinarily high uptake (7.6 times higher than 1), it was less potent than 1 (IC 50 = 0.18 muM versus 0.13 muM) even though they both showed similar sub-cellular localization patterns. This low potency was attributed to its high aggregation tendency in aqueous media (4 times higher than 1), which might have affected its ability to generate singlet oxygen in vitro . 8 on the other hand showed an even lower potency than 6 (2.28 vs 0.18 muM). However this was attributed to its low cellular uptake (20 times less than 6) and inefficient generation of singlet oxygen. Overall, although the structural modifications did improve the cellular uptake of 6, 6 was still less potent than the lead photosensitizers 1. Thus

DNA Duplex-Based Photodynamic Molecular Beacon for Targeted Killing of Retinoblastoma Cell.

PubMed

Wei, Yanchun; Lu, Cuixia; Chen, Qun; Xing, Da

2016-11-01

Retinoblastoma (RB) is the most common primary intraocular malignancy of infancy. An alternative RB treatment protocol is proposed and tested. It is based on a photodynamic therapy (PDT) with a designed molecular beacon that specifically targets the murine double minute x (MDMX) high-expressed RB cells. A MDMX mRNA triggered photodynamic molecular beacon is designed by binding a photosensitizer molecule (pyropheophorbide-a, or PPa) and a black hole quencher-3 (BHQ3) through a complementary oligonucleotide sequence. Cells with and without MDMX high-expression are incubated with the beacon and then irradiated with a laser. The fluorescence and reactive oxygen species are detected in solution to verify the specific activation of PPa by the perfectly matched DNA targets. The cell viabilities are evaluated with CCK-8 and flow cytometry assay. The fluorescence and photo-cytoxicity of PPa is recovered and significantly higher in the MDMX high-expressed Y79 and WERI-Rb1 cells, compared to that with the MDMX low-expressed cells. The synthesized beacon exhibits high PDT efficiency toward MDMX high-expressed RB cells. The data suggest that the designed beacon may provide a potential alternative for RB therapy and secures the ground for future investigation.

In Vitro Antimicrobial Photodynamic Therapy Against Trichophyton mentagrophytes Using New Methylene Blue as the Photosensitizer.

PubMed

López-Chicón, P; Gulías, Ò; Nonell, S; Agut, M

2016-11-01

Antimicrobial photodynamic therapy combines the use of a photosensitizing drug with light and oxygen to eradicate pathogens. Trichophyton mentagrophytes is a dermatophytic fungus able to invade the skin and keratinized tissues. We have investigated the use of new methylene blue as the photosensitizing agent for antimicrobial photodynamic therapy to produce the in vitro inactivation of T mentagrophytes. A full factorial design was employed to optimize the parameters for photoinactivation of the dermatophyte. The parameters studied were new methylene blue concentration, contact time between the photosensitizing agent and the fungus prior to light treatment, and the fluence of red light (wavelength, 620-645nm) applied. The minimum concentration of new methylene blue necessary to induce the death of all T. mentagrophytes cells in the initial suspension (approximate concentration, 10 6 colony forming units per milliliter) was 50μM for a fluence of 81J/cm 2 after a contact time of 10minutes with the photosensitizing-agent. Increasing the concentration to 100μM allowed the fluence to be decreased to 9J/cm 2 . Comparison of our data with other published data shows that the susceptibility of T. mentagrophytes to antimicrobial photodynamic therapy with new methylene blue is strain-dependent. New methylene blue is a photosensitizing agent that should be considered for the treatment of fungal skin infections caused by this dermatophyte. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

Activation of photodynamic therapy in vitro with Cerenkov luminescence generated from Yttrium-90 (Conference Presentation)

NASA Astrophysics Data System (ADS)

Hartl, Brad A.; Hirschberg, Henry; Marcu, Laura; Cherry, Simon R.

2016-03-01

Translation of photodynamic therapy to the clinical setting has primarily been limited to easily accessible and/or superficial diseases where traditional light delivery can be performed noninvasively. Cerenkov luminescence, as generated from medically relevant radionuclides, has been suggested as a means to deliver light to deeper tissues noninvasively in order to overcome this depth limitation. We report on the use of Cerenkov luminescence generated from Yttrium-90 as a means to active the photodynamic therapy process in monolayer tumor cell cultures. The current study investigates the utility of Cerenkov luminescence for activating both the clinically relevant aminolevulinic acid at 1.0 mM and also the more efficient photosensitizer TPPS2a at 1.2 µM. Cells were incubated with aminolevulinic acid for 6 hours prior to radionuclide addition, as well as additional daily treatments for three days. TPPS2a was delivered as a single treatment with an 18 hour incubation time before radionuclide addition. Experiments were completed for both C6 glioma cells and MDA-MB-231 breast tumor cells. Although aminolevulinic acid proved ineffective for generating a therapeutic effect at any activity for either cell line, TPPS2a produced at least a 20% therapeutic effect at activities ranging from 6 to 60 µCi/well for the C6 cell line. Current results demonstrate that it may be possible to generate a therapeutic effect in vivo using Cerenkov luminescence to activate the photodynamic therapy process with clinically relevant photosensitizers.

Amplifying the red-emission of upconverting nanoparticles for biocompatible clinically used prodrug-induced photodynamic therapy.

PubMed

Punjabi, Amol; Wu, Xiang; Tokatli-Apollon, Amira; El-Rifai, Mahmoud; Lee, Hyungseok; Zhang, Yuanwei; Wang, Chao; Liu, Zhuang; Chan, Emory M; Duan, Chunying; Han, Gang

2014-10-28

A class of biocompatible upconverting nanoparticles (UCNPs) with largely amplified red-emissions was developed. The optimal UCNP shows a high absolute upconversion quantum yield of 3.2% in red-emission, which is 15-fold stronger than the known optimal β-phase core/shell UCNPs. When conjugated to aminolevulinic acid, a clinically used photodynamic therapy (PDT) prodrug, significant PDT effect in tumor was demonstrated in a deep-tissue (>1.2 cm) setting in vivo at a biocompatible laser power density. Furthermore, we show that our UCNP-PDT system with NIR irradiation outperforms clinically used red light irradiation in a deep tumor setting in vivo. This study marks a major step forward in photodynamic therapy utilizing UCNPs to effectively access deep-set tumors. It also provides an opportunity for the wide application of upconverting red radiation in photonics and biophotonics.

MS2 bacteriophage as a delivery vessel of porphyrins for photodynamic therapy

NASA Astrophysics Data System (ADS)

Cohen, Brian A.; Kaloyeros, Alain E.; Bergkvist, Magnus

2011-02-01

Challenges associated with photodynamic therapy (PDT) include the packaging and site-specific delivery of therapeutic agents to the tissue of interest. Nanoscale encapsulation of PDT agents inside targeted virus capsids is a novel concept for packaging and site-specific targeting. The icosahedral MS2 bacteriophage is one potential candidate for such a packaging-system. MS2 has a porous capsid with an exterior diameter of ~28 nm where the pores allow small molecules access to the capsid interior. Furthermore, MS2 presents suitable residues on the exterior capsid for conjugation of targeting ligands. Initial work by the present investigators has successfully demonstrated RNA-based self-packaging of a heterocyclic PDT agent (meso-tetrakis(para-N-trimethylanilinium)porphine, TMAP) into the MS2 capsid. Packaging photoactive compounds in confined spaces could result in energy transfer between the molecules upon photoactivation, which could in turn reduce the production of radical oxygen species (ROS). ROS are key components in photodynamic therapy, and a reduced production could negatively impact the efficacy of PDT treatment. Here, findings are presented from an investigation of ROS generation of TMAP encapsulated within the MS2 capsid compared to free TMAP in solution. Monitoring of ROS production upon photoactivation via a specific singlet oxygen assay revealed the impact on ROS generation between packaged porphyrins as compared to free porphyrin in an aqueous solution. Follow on work will study the ability of MS2-packaged porphyrins to generate ROS in vitro and subsequent cytotoxic effects on cells in culture.

Photodynamic Therapy for Malignant Brain Tumors.

PubMed

Akimoto, Jiro

2016-01-01

Photodynamic therapy (PDT) using talaporfin sodium together with a semiconductor laser was approved in Japan in October 2003 as a less invasive therapy for early-stage lung cancer. The author believes that the principle of PDT would be applicable for controlling the invading front of malignant brain tumors and verified its efficacy through experiments using glioma cell lines and glioma xenograft models. An investigator-initiated clinical study was jointly conducted with Tokyo Women's Medical University with the support of the Japan Medical Association. Patient enrollment was started in May 2009 and a total of 27 patients were enrolled by March 2012. Of 22 patients included in efficacy analysis, 13 patients with newly diagnosed glioblastoma showed progression-free survival of 12 months, progression-free survival at the site of laser irradiation of 20 months, 1-year survival of 100%, and overall survival of 24.8 months. In addition, the safety analysis of the 27 patients showed that adverse events directly related to PDT were mild. PDT was approved in Japan for health insurance coverage as a new intraoperative therapy with the indication for malignant brain tumors in September 2013. Currently, the post-marketing investigation in the accumulated patients has been conducted, and the preparation of guidelines, holding training courses, and dissemination of information on the safe implementation of PDT using web sites and videos, have been promoted. PDT is expected to be a breakthrough for the treatment of malignant glioma as a tumor cell-selective less invasive therapy for the infiltrated functional brain area.

Combination of hyperthermia and photodynamic therapy on mesenchymal stem cell line treated with chloroaluminum phthalocyanine magnetic-nanoemulsion

NASA Astrophysics Data System (ADS)

de Paula, Leonardo B.; Primo, Fernando L.; Pinto, Marcelo R.; Morais, Paulo C.; Tedesco, Antonio C.

2015-04-01

The present study reports on the preparation and the cell viability assay of two nanoemulsions loaded with magnetic nanoparticle and chloroaluminum phthalocyanine. The preparations contain equal amount of chloroaluminum phthalocyanine (0.05 mg/mL) but different contents of magnetic nanoparticle (0.15×1013 or 1.50×1013 particle/mL). The human bone marrow mesenchymal stem cell line was used as the model to assess the cell viability and this type of cell can be used as a model to mimic cancer stem cells. The cell viability assays were performed in isolated as well as under combined magnetic hyperthermia and photodynamic therapy treatments. We found from the cell viability assay that under the hyperthermia treatment (1 MHz and 40 Oe magnetic field amplitude) the cell viability reduction was about 10%, regardless the magnetic nanoparticle content within the magnetic nanoparticle/chloroaluminum phthalocyanine formulation. However, cell viability reduction of about 50% and 60% were found while applying the photodynamic therapy treatment using the magnetic nanoparticle/chloroaluminum phthalocyanine formulation containing 0.15×1013 or 1.50×1013 magnetic particle/mL, respectively. Finally, an average reduction in cell viability of about 66% was found while combining the hyperthermia and photodynamic therapy treatments.

Comparing clinical effects of photodynamic therapy as a novel method with topical corticosteroid for treatment of Oral Lichen Planus.

PubMed

Bakhtiari, Sedigheh; Azari-Marhabi, Saranaz; Mojahedi, Seyyed Masoud; Namdari, Mahshid; Rankohi, Zahra Elmi; Jafari, Soudeh

2017-12-01

Oral lichen planus is an autoimmune disorder with several challenges in treatment. Photodynamic therapy has been proposed as a new treatment option for the disease. The present study compared the clinical effects of photodynamic therapy to dexamethasone mouthwash in the treatment of oral lichen planus lesions. In this randomized clinical trial, 30 patients with oral lichen planus were included.15 patients were treated with 5% methylene blue mediated photodynamic therapy using Fotosan device for 30s (630nm wavelength and 7.2-14.4J/cm 2 dose) for 4 sessions in the days 1, 4, 7, 14. In another group, the treatment was done on 15 patients by 0.5mg tab dexamethasone solution in 5cc water, rinsed 4 times in a day within two weeks. The sign score, symptoms scores (pain), clinical severity and treatment efficacy were measured at the days 15, 30, 60, 90 after beginning of the treatment. The results were subjected to Mann-whitney U test in both groups. No significant difference existed between the two modalities regarding the treatment efficacy index, sign score, symptom score and clinical severity on the 15, 30, 60 and 90 post-treatment days. Decreases in patient's symptoms were statistically significant in both groups. Photodynamic therapy was as effective as the dexamethasone mouth wash in the treatment of oral lichen planus. It could be used as a safe modality in the treatment of oral lichen planus lesions without identified side effects. Copyright © 2017 Elsevier B.V. All rights reserved.

``Smart'' theranostic lanthanide nanoprobes with simultaneous up-conversion fluorescence and tunable T1-T2 magnetic resonance imaging contrast and near-infrared activated photodynamic therapy

NASA Astrophysics Data System (ADS)

Zhang, Yan; Das, Gautom Kumar; Vijayaragavan, Vimalan; Xu, Qing Chi; Padmanabhan, Parasuraman; Bhakoo, Kishore K.; Tamil Selvan, Subramanian; Tan, Timothy Thatt Yang

2014-10-01

The current work reports a type of ``smart'' lanthanide-based theranostic nanoprobe, NaDyF4:Yb3+/NaGdF4:Yb3+,Er3+, which is able to circumvent the up-converting poisoning effect of Dy3+ ions to give efficient near infrared (980 nm) triggered up-conversion fluorescence, and offers not only excellent dark T2-weighted MR contrast but also tunable bright and T1-weighted MR contrast properties. Due to the efficient up-converted energy transfer from the nanocrystals to chlorin e6 (Ce6) photosensitizers loaded onto the nanocrystals, cytotoxic singlet oxygen was generated and photodynamic therapy was demonstrated. Therefore, the current multifunctional nanocrystals could be potentially useful in various image-guided diagnoses where bright or dark MRI contrast could be selectively tuned to optimize image quality, but also as an efficient and more penetrative near-infrared activated photodynamic therapy agent.The current work reports a type of ``smart'' lanthanide-based theranostic nanoprobe, NaDyF4:Yb3+/NaGdF4:Yb3+,Er3+, which is able to circumvent the up-converting poisoning effect of Dy3+ ions to give efficient near infrared (980 nm) triggered up-conversion fluorescence, and offers not only excellent dark T2-weighted MR contrast but also tunable bright and T1-weighted MR contrast properties. Due to the efficient up-converted energy transfer from the nanocrystals to chlorin e6 (Ce6) photosensitizers loaded onto the nanocrystals, cytotoxic singlet oxygen was generated and photodynamic therapy was demonstrated. Therefore, the current multifunctional nanocrystals could be potentially useful in various image-guided diagnoses where bright or dark MRI contrast could be selectively tuned to optimize image quality, but also as an efficient and more penetrative near-infrared activated photodynamic therapy agent. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr01717j

Advance in Photosensitizers and Light Delivery for Photodynamic Therapy

PubMed Central

Yoon, Il; Li, Jia Zhu

2013-01-01

The brief history of photodynamic therapy (PDT) research has been focused on photosensitizers (PSs) and light delivery was introduced recently. The appropriate PSs were developed from the first generation PS Photofrin (QLT) to the second (chlorins or bacteriochlorins derivatives) and third (conjugated PSs on carrier) generations PSs to overcome undesired disadvantages, and to increase selective tumor accumulation and excellent targeting. For the synthesis of new chlorin PSs chlorophyll a is isolated from natural plants or algae, and converted to methyl pheophorbide a (MPa) as an important starting material for further synthesis. MPa has various active functional groups easily modified for the preparation of different kinds of PSs, such as methyl pyropheophorbide a, purpurin-18, purpurinimide, and chlorin e6 derivatives. Combination therapy, such as chemotherapy and photothermal therapy with PDT, is shortly described here. Advanced light delivery system is shown to establish successful clinical applications of PDT. Phtodynamic efficiency of the PSs with light delivery was investigated in vitro and/or in vivo. PMID:23423543

Electroporation enhances antimicrobial photodynamic therapy mediated by the hydrophobic photosensitizer, hypericin, Electroporation enhances antimicrobial photodynamic inactivation

PubMed Central

de Melo, Wanessa de Cássia Martins Antunes; Lee, Alexander N; Perussi, Janice Rodrigues; Hamblin, Michael R.

2013-01-01

The effective transport of photosensitizers (PS) across the membrane and the intracellular accumulation of PS are the most crucial elements in antimicrobial photodynamic therapy (aPDT). However, due to the morphological complexity of Gram-negative bacteria the penetration of PS is limited, especially hydrophobic PS. Electroporation (EP) could increase the effectiveness of aPDT, by promoting the formation of transient pores that enhance the permeability of the bacterial membrane to PS. In this study we evaluated the combination of aPDT mediated by the hydrophobic PS, hypericin and EP (aPDT/EP) against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. These bacteria were exposed to light (590 nm) in the presence of hypericin (4µM), following electroporation. The results showed that aPDT/EP inactivated 3.67 logs more E. coli and 2.65 logs more S. aureus than aPDT alone. Based on these results we suggest that EP can potentiate the aPDT effect. PMID:24284122

cRGD Peptide-Conjugated Pyropheophorbide-a Photosensitizers for Tumor Targeting in Photodynamic Therapy.

PubMed

Li, Wenjing; Tan, Sihai; Xing, Yutong; Liu, Qian; Li, Shuang; Chen, Qingle; Yu, Min; Wang, Fengwei; Hong, Zhangyong

2018-04-02

Pyropheophorbide-a (Pyro) is a highly promising photosensitizer for tumor photodynamic therapy (PDT), although its very limited tumor-accumulation ability seriously restricts its clinical applications. A higher accumulation of photosensitizers is very important for the treatment of deeply seated and larger tumors. The conjugation of Pyro with tumor-homing peptide ligands could be a very useful strategy to optimize the physical properties of Pyro. Herein, we reported our studies on the conjugation of Pyro with a cyclic cRGDfK (cRGD) peptide, an integrin binding sequence, to develop highly tumor-specific photosensitizers for PDT application. To further reduce the nonspecific uptake and, thus, reduce the background distribution of the conjugates in normal tissues, we opted to add a highly hydrophilic polyethylene glycol (PEG) chain and an extra strongly hydrophilic carboxylic acid group as the linker to avoid the direct connection of the strongly hydrophobic Pyro macrocycle and cRGD ligand. We reported here the synthesis and characterization of these conjugates, and the influence of the hydrophilic modification on the biological function of the conjugates was carefully studied. The tumor-accumulation ability and photodynamic-induced cell-killing ability of these conjugates were evaluated through both in vitro cell-based experiment and in vivo distribution and tumor therapy experiments with tumor-bearing mice. Thus, the synthesized conjugate significantly improved the tumor enrichment and tumor selectivity of Pyro, as well as abolished the xenograft tumors in the murine model through a one-time PDT treatment.

Application of photodynamic therapy, laser therapy, and a cellulose membrane for calcaneal pressure ulcer treatment in a diabetic patient: A case report.

PubMed

Rosa, Luciano Pereira; da Silva, Francine Cristina; Vieira, Regiane Lima; Tanajura, Beatriz Rocha; da Silva Gusmão, Alana Gonçalves; de Oliveira, Janeide Muritiba; Dos Santos, Nathalia Aparecida Campanário; Bagnato, Vanderlei Salvador

2017-09-01

Diabetes mellitus is a metabolic disorder in which a person has high blood glucose levels due to inadequate insulin production by the pancreas. Wounds in these individuals cannot heal properly over time due to circulatory changes that hinder and stagnate the healing process. We report the case of an 82-year-old female type 2 diabetes mellitus carrier, presenting to clinical-dermatological examination pressure ulcer (PU) in the right calcaneus region. The patient was treated with photodynamic therapy using curcumin and blue light-emitting diodes (LEDs), laser therapy, and the application of a cellulose membrane in order to promote ulcer decontamination by local action, accelerate wound healing, and maintain favorable conditions of asepsis and moisture, respectively. The ulcer healing occurred after 30days of treatment and total epithelialization was observed. From the results obtained in this case report, we conclude that the combination of photodynamic therapy, laser therapy, and coating with a cellulose membrane is a promising treatment for the healing of PU in diabetic patients. Copyright © 2017 Elsevier B.V. All rights reserved.

In vivo relaxation time measurements on a murine tumor model--prolongation of T1 after photodynamic therapy.

PubMed

Liu, Y H; Hawk, R M; Ramaprasad, S

1995-01-01

RIF tumors implanted on mice feet were investigated for changes in relaxation times (T1 and T2) after photodynamic therapy (PDT). Photodynamic therapy was performed using Photofrin II as the photosensitizer and laser light at 630 nm. A home-built proton solenoid coil in the balanced configuration was used to accommodate the tumors, and the relaxation times were measured before, immediately after, and up to several hours after therapy. Several control experiments were performed untreated tumors, tumors treated with Photofrin II alone, or tumors treated with laser light alone. Significant increases in T1s of water protons were observed after PDT treatment. In all experiments, 31P spectra were recorded before and after the therapy to study the tumor status and to confirm the onset of PDT. These studies show significant prolongation of T1s after the PDT treatment. The spin-spin relaxation measurements, on the other hand, did not show such prolongation in T2 values after PDT treatment.

Physiological considerations acting on triplet oxygen for explicit dosimetry in photodynamic therapy.

PubMed

Sánchez, Víctor; Romero, María Paulina; Pratavieira, Sebastião; Costa, César

2017-09-01

The aims of this study were to determine the spatial and temporal theoretical distribution of the concentrations of Protoporphyrin IX, 3 O 2 and doses of 1 O 2 . The type II mechanism and explicit dosimetry in photodynamic therapy were used. Furthermore, the mechanism of respiration and cellular metabolism acting on 3 O 2 were taken into account. The dermis was considered as an absorbing and a scattering medium. An analytical solution was used for light diffusion in the skin. The photophysical, photochemical and biological effects caused by PDT with the initial irradiances of 20, 60 and 150mW/cm 2 were studied for a time of exposure of 20min and a maximum depth of 0.5cm. We found that the initial irradiance triples its value in 0.02cm and that almost 100% of PpIX is part of the dynamics of reactions in photodynamic therapy. Additionally, with about 40μMof 3 O 2 there is a balance between the consumed and supplied oxygen. Finally, we determined that with 60mW/cm 2 , the highest dose of 1 O 2 is obtained. Copyright © 2017 Elsevier B.V. All rights reserved.

Photodynamic therapy: a review of applications in neurooncology and neuropathology

NASA Astrophysics Data System (ADS)

Uzdensky, Anatoly B.; Berezhnaya, Elena; Kovaleva, Vera; Neginskaya, Marya; Rudkovskii, Mikhail; Sharifulina, Svetlana

2015-06-01

Photodynamic therapy (PDT) effect is a promising adjuvant modality for diagnosis and treatment of brain cancer. It is of importance that the bright fluorescence of most photosensitizers provides visualization of brain tumors. This is successfully used for fluorescence-guided tumor resection according to the principle "to see and to treat." Non-oncologic application of PDT effect for induction of photothrombotic infarct of the brain tissue is a well-controlled and reproducible stroke model, in which a local brain lesion is produced in the predetermined brain area. Since normal neurons and glial cells may also be damaged by PDT and this can lead to unwanted neurological consequences, PDT effects on normal neurons and glial cells should be comprehensively studied. We overviewed the current literature data on the PDT effect on a range of signaling and epigenetic proteins that control various cell functions, survival, necrosis, and apoptosis. We hypothesize that using cell-specific inhibitors or activators of some signaling proteins, one can selectively protect normal neurons and glia, and simultaneously exacerbate photodynamic damage of malignant gliomas.

Oncologic photodynamic diagnosis and therapy: confocal Raman/fluorescence imaging of metal phthalocyanines in human breast cancer tissue in vitro.

PubMed

Abramczyk, Halina; Brozek-Pluska, Beata; Surmacki, Jakub; Musial, Jacek; Kordek, Radzislaw

2014-11-07

Raman microspectroscopy and confocal Raman imaging combined with confocal fluorescence were used to study the distribution and aggregation of aluminum tetrasulfonated phthalocyanine (AlPcS4) in noncancerous and cancerous breast tissues. The results demonstrate the ability of Raman spectroscopy to distinguish between noncancerous and cancerous human breast tissue and to identify differences in the distribution and aggregation of aluminum phthalocyanine, which is a potential photosensitizer in photodynamic therapy (PDT), photodynamic diagnosis (PDD) and photoimmunotherapy (PIT) of cancer. We have observed that the distribution of aluminum tetrasulfonated phthalocyanine confined in cancerous tissue is markedly different from that in noncancerous tissue. We have concluded that Raman imaging can be treated as a new and powerful technique useful in cancer photodynamic therapy, increasing our understanding of the mechanisms and efficiency of photosensitizers by better monitoring localization in cancer cells as well as the clinical assessment of the therapeutic effects of PDT and PIT.

Photodynamic antimicrobial therapy to inhibit pseudomonas aeruginosa of corneal isolates (Conference Presentation)

NASA Astrophysics Data System (ADS)

Durkee, Heather A.; Relhan, Nidhi; Arboleda, Alejandro; Halili, Francisco; De Freitas, Carolina; Alawa, Karam; Aguilar, Mariela C.; Amescua, Guillermo; Miller, Darlene; Parel, Jean-Marie

2016-03-01

Keratitis associated with Pseudomonas aeruginosa is difficult to manage. Treatment includes antibiotic eye drops, however, some strains of Pseudomonas aeruginosa are resistant. Current research efforts are focused on finding alternative and adjunct therapies to treat multi-drug resistant bacteria. One promising alternate technique is photodynamic therapy (PDT). The purpose of this study was to evaluate the effect of riboflavin- and rose bengal-mediated PDT on Pseudomonas aeruginosa keratitis isolates in vitro. Two isolates (S+U- and S-U+) of Pseudomonas aeruginosa were derived from keratitis patients and exposed to five experimental groups: (1) Control (dark, UV-A irradiation, 525nm irradiation); (2) 0.1% riboflavin (dark, UV-A irradiation); and (3) 0.1% rose bengal, (4) 0.05% rose bengal and (5) 0.01% rose bengal (dark, 525nm irradiation). Three days after treatment, in dark conditions of all concentration of riboflavin and rose bengal showed no inhibition in both S+U- and S-U+ strains of Pseudomonas aeruginosa. In 0.1% and 0.05% rose bengal irradiated groups, for both S+U- and S-U+ strains, there was complete inhibition of bacterial growth in the central 50mm zone corresponding to the diameter of the green light source. These in vitro results suggest that rose bengal photodynamic therapy may be an effective adjunct treatment for Pseudomonas aeruginosa keratitis.

Regulation of miRNA Expression by Low-Level Laser Therapy (LLLT) and Photodynamic Therapy (PDT)

PubMed Central

Kushibiki, Toshihiro; Hirasawa, Takeshi; Okawa, Shinpei; Ishihara, Miya

2013-01-01

Applications of laser therapy, including low-level laser therapy (LLLT), phototherapy and photodynamic therapy (PDT), have been proven to be beneficial and relatively less invasive therapeutic modalities for numerous diseases and disease conditions. Using specific types of laser irradiation, specific cellular activities can be induced. Because multiple cellular signaling cascades are simultaneously activated in cells exposed to lasers, understanding the molecular responses within cells will aid in the development of laser therapies. In order to understand in detail the molecular mechanisms of LLLT and PDT-related responses, it will be useful to characterize the specific expression of miRNAs and proteins. Such analyses will provide an important source for new applications of laser therapy, as well as for the development of individualized treatments. Although several miRNAs should be up- or down-regulated upon stimulation by LLLT, phototherapy and PDT, very few published studies address the effect of laser therapy on miRNA expression. In this review, we focus on LLLT, phototherapy and PDT as representative laser therapies and discuss the effects of these therapies on miRNA expression. PMID:23807510

Regulation of miRNA expression by low-level laser therapy (LLLT) and photodynamic therapy (PDT).

PubMed

Kushibiki, Toshihiro; Hirasawa, Takeshi; Okawa, Shinpei; Ishihara, Miya

2013-06-27

Applications of laser therapy, including low-level laser therapy (LLLT), phototherapy and photodynamic therapy (PDT), have been proven to be beneficial and relatively less invasive therapeutic modalities for numerous diseases and disease conditions. Using specific types of laser irradiation, specific cellular activities can be induced. Because multiple cellular signaling cascades are simultaneously activated in cells exposed to lasers, understanding the molecular responses within cells will aid in the development of laser therapies. In order to understand in detail the molecular mechanisms of LLLT and PDT-related responses, it will be useful to characterize the specific expression of miRNAs and proteins. Such analyses will provide an important source for new applications of laser therapy, as well as for the development of individualized treatments. Although several miRNAs should be up- or down-regulated upon stimulation by LLLT, phototherapy and PDT, very few published studies address the effect of laser therapy on miRNA expression. In this review, we focus on LLLT, phototherapy and PDT as representative laser therapies and discuss the effects of these therapies on miRNA expression.

Synthesis and in vitro photodynamic therapy of chlorin derivative 131-ortho-trifluoromethyl-phenylhydrazone modified pyropheophorbide-a.

PubMed

Cheng, Jianjun; Li, Wenting; Tan, Guanghui; Wang, Zhiqiang; Li, Shuying; Jin, Yingxue

2017-03-01

Photodynamic therapy (PDT) is entering the mainstream of the cancer treatments recently. Pyropheophorbide-a (Pa), as a degradation product of chlorophyll-a, has been shown to be a potent photosensitizer in photodynamic therapy. In this paper, we investigated the in vitro photodynamic therapy of 13 1 -ortho-trifluoromethyl-phenylhydrazone modified pyropheophorbide-a (PHPa) against human HeLa cervical cancer cell line, together with ultraviolet-visible spectra, fluorescence emission spectra, stability in various solvents, and single oxygen quantum yield. The results indicated that PHPa not only showed a greater molar extinction coefficient reached 4.55×10 4  Lmol -1 cm -1 , the long absorption wavelength (681nm) as we expected that makes it potential in deep tumor treatment, but also showed better stability in near neutral phosphate buffers (pH 7.4) and culture medium, as well as higher single oxygen quantum yield (Ф D =40.5%) in DMF solutions. Moreover, cell experiments suggested that PHPa could be uptaken by HeLa cells successfully, and has low dark toxicity without irradiation, but remarkable photo-cytotoxicity (IC 50 , 1.92±0.59μM) that the inhibition rate of HeLa cells could increase up 91.4% at 30μM of PHPa after irradiation. In addition, morphological changes of HeLa cells further demonstrated that PHPa can induce damage and apoptotic cell death. Furthermore, the mechanism of photochemical processes was investigated by using specific quenching agent sodium azide (SA) and D-mannitol (DM), respectively, which showed the formation of singlet oxygen (Type II reaction mechanism) may play a predominant role, Type I and Type II photodynamic reactions could occur simultaneously in this PHPa mediated PDT process. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Acridine Orange as a Novel Photosensitizer for Photodynamic Therapy in Glioblastoma.

PubMed

Osman, Hany; Elsahy, Deena; Saadatzadeh, M Reza; Pollok, Karen E; Yocom, Steven; Hattab, Eyas M; Georges, Joseph; Cohen-Gadol, Aaron A

2018-06-01

Photodynamic therapy combines the effects of a chemical agent with the physical energy from light or radiation to result in lysis of cells. Acridine orange (AO) is a molecule with fluorescence properties that has been demonstrated to possess photosensitizing properties. The objective of this study was to investigate the photodynamic effect of AO on glioblastoma cell viability and growth. Glioblastoma cells (N = 8000 cells/well at 0 hours) were exposed to AO followed by white unfiltered light-emitting diode light. Cultures were exposed to either 10 or 30 minutes of light. The cell number per well was determined at 0, 24, 48, and 72 hours after exposure. A dramatic cytocidal effect of AO after exposure to 10 minutes of white light was observed. There was almost complete eradication of glioblastoma cells over a 72-hour period. Although AO or light alone exhibited some effect on cell growth, it was not as pronounced as the combination of AO and light. This is the first study to our knowledge to demonstrate the photodynamic effect of AO in glioblastoma cells. These data support the need for further studies to characterize and evaluate whether this striking cytotoxic effect can be achieved in vivo. The combination of AO and exposure to white unfiltered light-emitting diode light may have potential future applications in management of glioblastoma. Copyright © 2018 Elsevier Inc. All rights reserved.

Porphyrin-based polysilsesquioxane nanoparticles to improve photodynamic therapy for cancer treatment

NASA Astrophysics Data System (ADS)

Vivero-Escoto, Juan L.; DeCillis, Daniel; Fritts, Laura; Vega, Daniel L.

2014-03-01

Photodynamic therapy (PDT) has emerged as an alternative approach to chemotherapy and radiotherapy for cancer treatment. The photosensitizer (PS) is perhaps the most critical component of PDT, and continues to be an area of intense scientific research. Traditionally, PS molecules (e.g. porphyrins) have dominated the field. Nevertheless, these PS agents have several disadvantages, with low water solubility, poor light absorption and reduced selectivity for targeted tissues being some of the main drawbacks. Polysilsesquioxane (PSilQ) nanoparticles are crosslinked homopolymers formed by the condensation of functionalized trialkoxysilanes or bis(trialkoxysilanes). We believe that PSilQ particles provide an interesting platform for developing PS nanocarriers. Several advantages can be foreseen by using this platform such as carrying a large payload of PS molecules; their surface and composition can be tailored to develop multifunctional systems (e.g. target-specific); and due to their small size, nanoparticles can penetrate deep into tissues and be readily internalized by cells. In this work, PSilQ nanoparticles with a high payload of photosensitizers were synthesized, characterized, and applied in vitro. The network of this nanomaterial is formed by protoporphyrin IX (PpIX) molecules chemically connected via a redox-responsive linker. Under reducing environment such as the one found in cancer cells the nanoparticles can be degraded to efficiently release single photosensitizers in the cytoplasm. The phototoxicity of this porphyrin-based PSilQ nanomaterial was successfully demonstrated in vitro using human cervical (HeLa) cancer cells. We envision that this platform can be further functionalized with polyethylene glycol (PEG) and targeting ligands to improve its biocompatibility and target specificity.

Three-dimensional illumination procedure for photodynamic therapy of dermatology

NASA Astrophysics Data System (ADS)

Hu, Xiao-ming; Zhang, Feng-juan; Dong, Fei; Zhou, Ya

2014-09-01

Light dosimetry is an important parameter that affects the efficacy of photodynamic therapy (PDT). However, the irregular morphologies of lesions complicate lesion segmentation and light irradiance adjustment. Therefore, this study developed an illumination demo system comprising a camera, a digital projector, and a computing unit to solve these problems. A three-dimensional model of a lesion was reconstructed using the developed system. Hierarchical segmentation was achieved with the superpixel algorithm. The expected light dosimetry on the targeted lesion was achieved with the proposed illumination procedure. Accurate control and optimization of light delivery can improve the efficacy of PDT.

Antimicrobial Photodynamic Therapy to Kill Gram-negative Bacteria

PubMed Central

Sperandio, Felipe F; Huang, Ying-Ying; Hamblin, Michael R

2013-01-01

Antimicrobial photodynamic therapy (PDT) or photodynamic inactivation (PDI) is a new promising strategy to eradicate pathogenic microorganisms such as Gram-positive and Gram-negative bacteria, yeasts and fungi. The search for new approaches that can kill bacteria but do not induce the appearance of undesired drug-resistant strains suggests that PDT may have advantages over traditional antibiotic therapy. PDT is a non-thermal photochemical reaction that involves the simultaneous presence of visible light, oxygen and a dye or photosensitizer (PS). Several PS have been studied for their ability to bind to bacteria and efficiently generate reactive oxygen species (ROS) upon photostimulation. ROS are formed through type I or II mechanisms and may inactivate several classes of microbial cells including Gram-negative bacteria such as Pseudomonas aeruginosa, which are typically characterized by an impermeable outer cell membrane that contains endotoxins and blocks antibiotics, dyes, and detergents, protecting the sensitive inner membrane and cell wall. This review covers significant peer-reviewed articles together with US and World patents that were filed within the past few years and that relate to the eradication of Gram-negative bacteria via PDI or PDT. It is organized mainly according to the nature of the PS involved and includes natural or synthetic food dyes; cationic dyes such as methylene blue and toluidine blue; tetrapyrrole derivatives such as phthalocyanines, chlorins, porphyrins, chlorophyll and bacteriochlorophyll derivatives; functionalized fullerenes; nanoparticles combined with different PS; other formulations designed to target PS to bacteria; photoactive materials and surfaces; conjugates between PS and polycationic polymers or antibodies; and permeabilizing agents such as EDTA, PMNP and CaCl2. The present review also covers the different laboratory animal models normally used to treat Gram-negative bacterial infections with antimicrobial PDT. PMID

Vaginal Speculum For Photodynamic Therapy And Method Of Using The Same

DOEpatents

Tadir, Yona; Berns, Michael W.; Monk, Brad J.; Profeta, Glen; Tromberg, Bruce J.

1995-10-17

An improved vaginal speculum for photodynamic therapy of intraepithelial tissue and in particular vaginal, cervical and vulvar neoplasia utilizes a precisely and accurately positionable optic fiber through which a predetermined dose of light in the range of 620 to 700 nanometers is delivered over a controlled area which has been previously treated with photodynamic therapeutic substances. In particular, the neoplastic area has been treated with hematoporphyrin derivatives and other photosensitizers which are selectively taken into the cancerous tissue. Exposure to the appropriate wavelength laser light photoactivates the absorbed hematoporphyrins causing the release of singlet oxygen which internally oxidizes and ultimately causes cell death. The fiber optic tip from which the laser light is transmitted is precisely positioned within the body cavity at a predetermined distance from the intraepithelial neoplasia in order to obtain the appropriate spot size and location to minimize damage to healthy tissue and maximize damage to the selectively impregnated cancerous tissue.

TOPICAL REVIEW: The physics, biophysics and technology of photodynamic therapy

NASA Astrophysics Data System (ADS)

Wilson, Brian C.; Patterson, Michael S.

2008-05-01

Photodynamic therapy (PDT) uses light-activated drugs to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections. This paper reviews the current status of PDT with an emphasis on the contributions of physics, biophysics and technology, and the challenges remaining in the optimization and adoption of this treatment modality. A theme of the review is the complexity of PDT dosimetry due to the dynamic nature of the three essential components—light, photosensitizer and oxygen. Considerable progress has been made in understanding the problem and in developing instruments to measure all three, so that optimization of individual PDT treatments is becoming a feasible target. The final section of the review introduces some new frontiers of research including low dose rate (metronomic) PDT, two-photon PDT, activatable PDT molecular beacons and nanoparticle-based PDT.

Physical and mathematical modeling of antimicrobial photodynamic therapy

NASA Astrophysics Data System (ADS)

Bürgermeister, Lisa; López, Fernando Romero; Schulz, Wolfgang

2014-07-01

Antimicrobial photodynamic therapy (aPDT) is a promising method to treat local bacterial infections. The therapy is painless and does not cause bacterial resistances. However, there are gaps in understanding the dynamics of the processes, especially in periodontal treatment. This work describes the advances in fundamental physical and mathematical modeling of aPDT used for interpretation of experimental evidence. The result is a two-dimensional model of aPDT in a dental pocket phantom model. In this model, the propagation of laser light and the kinetics of the chemical reactions are described as coupled processes. The laser light induces the chemical processes depending on its intensity. As a consequence of the chemical processes, the local optical properties and distribution of laser light change as well as the reaction rates. The mathematical description of these coupled processes will help to develop treatment protocols and is the first step toward an inline feedback system for aPDT users.

Targeted photodynamic therapy for infected wounds in mice

NASA Astrophysics Data System (ADS)

Hamblin, Michael R.; O'Donnell, David A.; Zahra, Touqir; Contag, Christopher H.; McManus, Albert T.; Hasan, Tayyaba

2002-06-01

Although many workers have used photodynamic therapy to kill bacteria in vitro, the use of this approach has seldom been reported in vivo in animal models of infection. We report on the use of a targeted polycationic photosensitizer conjugate between poly-L-lysine and chlorin(e6) that can penetrate the Gram (-) outer membrane together with red laser light to kill Escherichia coli and Pseudomonas aeruginosa infecting excisional wounds in mice. We used genetically engineered luminescent bacteria that allowed the infection to be imaged in mouse wounds using a sensitive CCD camera. Wounds were infected with 5x106 bacteria, followed by application of the conjugate in solution and illumination. There was a light-dose dependent loss of luminescence as measured by image analysis in the wound treated with conjugate and light, not seen in control wounds. This strain of E coli is non-invasive and the infection in untreated wounds spontaneously resolved in a few days and all wounds healed equally well showing the photodynamic treatment did not damage the host tissue. P aeruginosa is highly invasive and mice with untreated or control wounds all died while 90% of PDT treated mice survived. PDT may have a role to play in the rapid treatment of infected wounds in view of the worldwide rise in antibiotic resistance.

Two-step irradiance schedule versus single-dose tramadol sustained-release tablets for pain control during topical 5-aminolevulinic acid-photodynamic therapy of condyloma acuminatum in Chinese patients: a randomized comparative study.

PubMed

Mchepange, Uwesu O; Huang, Chun-Yan; Sun, Yi; Tu, Ya-Ting; Tao, Juan

2014-07-01

Photodynamic therapy with 5-aminolevulinic acid (ALA-PDT) offers promising results for the treatment of condyloma acuminatum. However, patients have to dwell with pain to benefit from this otherwise effective and safe "off-label" treatment modality. Several techniques have been explored to control ALA-PDT-induced pain, but the desperate search for a universally accepted method is still ongoing. This study compares the two-step irradiance approach with single-dose administration of 100 mg tramadol sustained-release tablets for pain induced by ALA-PDT of condyloma acuminatum in Chinese patients. Adult Chinese patients with condyloma acuminatum were enrolled in a randomized comparative study. Pain levels were compared using the Numeric Rating Scale (NRS) at pre-defined assessment points during and after irradiation. The pain was dominated by characteristics such as burning and pricking and was almost always local and superficial. The median pain scores were lower in the two-step irradiance group at 1 minute (U = 621.5, P = 0.002) but higher at 20 minutes (U = 585.5, P = 0.002). The median pain scores between the two groups did not differ significantly at other assessment points. The pain was moderate in both groups and peaked earlier in the analgesics group (median: 5 minutes) but later in the two-step irradiance group (median: 15 minutes). The pain was generally mild. The median pain scores were equal at each assessment point, except at 3 hours where the median was lower in the analgesics group (1.0) as compared with the two-step irradiance group (2.0) (U = 725.0, P = 0.056). Pain in the two-step irradiance protocol is irradiance-dependent. The two-step irradiance approach produces significant benefits over analgesics during the initial stages of therapy but analgesics offer significant benefits thereafter. There are potential benefits of combining the two approaches in minimizing ALA-PDT-induced pain. © 2014 Wiley Periodicals

Decreased metastatic phenotype in cells resistant to Aminolevulinic acid-Photodynamic therapy

PubMed Central

Casas, Adriana; Di Venosa, Gabriela; Vanzulli, Silvia; Perotti, Christian; Mamome, Leandro; Rodriguez, Lorena; Simian, Marina; Juarranz, Angeles; Pontiggia, Osvaldo; Hasan, Tayyaba; Batlle, Alcira

2008-01-01

Photodynamic therapy (PDT) is a novel cancer treatment utilising a photosensitiser, visible light and oxygen. PDT often leaves a significant number of surviving tumour cells. In a previous work, we isolated and studied two PDT resistant clones derived from the mammary adenocarcinoma LM3 line (Int. J. Oncol. 29 (2006) 397–405). The isolated Clon 4 and Clon 8 exhibited a more fibroblastic, dendritic pattern and were larger than the parentals. In the present work we studied the metastatic potential of the two clones in comparison with LM3. We found that 100 % of LM3 invaded Matrigel, whereas only 19 ± 6 % and 24 ± 7 % of Clon 4 and Clon 8 cells invaded. In addition, 100% of LM3 cells migrated towards a chemotactic stimulus whereas 38 ± 8 % and 73 ± 10 % of Clones 4 and 8 respectively were able to migrate. In vivo, 100% of the LM3 injected mice developed spontaneous lung metastasis, whereas none of the Clon 8 did, and only one of the mice injected with Clon 4 did. No differences were found in the proteolytic enzyme profiles among the cells. Anchorage-dependent adhesion was also impaired in vivo in the resistant clones, evidenced by the lower tumour take, latency time and growth rates, although both clones showed in vitro higher binding to collagen I without overexpression of β1 integrin. This is the first work where the metastatic potential of cells surviving to PDT has been studied. PDT strongly affects the invasive phenotype of these cells, probably related to a higher binding to collagen. These findings may be crucial for the outcome of ALA-PDT of metastatic tumours, although further studies are needed to extrapolate the results to the clinic employing another photosensitisers and cell types. PMID:18662847

Light distribution in the endometrium during photodynamic therapy

NASA Astrophysics Data System (ADS)

Madsen, Sten; Svaasand, Lars O.; Fehr, Mathias K.; Tadir, Yona; Ngo, Phat; Tromberg, Bruce J.

1995-01-01

Hysterectomy is the most common major operation performed in the United States with dysfunctional uterine bleeding being a major indication. Endometrial destruction by photodynamic therapy (PDT) has been suggested as a possible alternative to invasive surgical procedures for abnormal uterine bleeding due to benign changes. Effective destruction of the endometrium during PDT requires a sufficient amount of light to be delivered to the entire endometrium in a reasonable time. To satisfy these criteria, we have developed a trifurcated optical applicator consisting of three cylindrical diffusing fibers. The applicator was inserted into freshly excised, intact human uteri and the optical distribution was measured with an isotropic fiber probe at various locations in the uterus. The results were in good agreement with the predictions of a mathematical model based on diffusion theory. The results indicate that irradiation of the endometrium by the trifurcated applicator can destroy tissue to a depth of 4 mm given an optical power of 100 mW per cm of diffusing tip (100 mW/cm) for an exposure time of less than 20 minutes.

Preparation and characterization of bioadhesive system containing hypericin for local photodynamic therapy.

PubMed

Borghi-Pangoni, Fernanda Belincanta; Junqueira, Mariana Volpato; de Souza Ferreira, Sabrina Barbosa; Silva, Larissa Lachi; Rabello, Bruno Ribeiro; de Castro, Lidiane Vizioli; Baesso, Mauro Luciano; Diniz, Andréa; Caetano, Wilker; Bruschi, Marcos Luciano

2017-09-01

Hypericin (Hyp) is a natural photoactive pigment utilized in the treatment of different types of cancer and antimicrobial inactivation using photodynamic therapy (PDT). Hyp is poorly soluble in water leading to problems of administration, getting close contact with the site, and bio-availability. Therefore, this study aimed to develop bioadhesive thermoresponsive system containing Hyp for local PDT. Carbomer 934P, poloxamer 407, and Hyp were used to prepare the thermoresponsive bioadhesive formulations. They were characterized for sol-gel transition temperature, mechanical, mucoadhesive, rheological (continuous flow and oscillatory) and dielectric properties, syringeability, in vitro Hyp release kinetics, ex vivo permeability, and photodynamic activity. The formulations displayed suitable gelation temperature and rheological characteristics. The compressional, mechanical and mucoadhesive properties, as well the syringeability showed the easiness of administration and the permanence of the system adhered to the mucosa or skin. The dielectric analysis helped to understand the Hyp availability, and its release presented an anomalous behavior. The system did not permeate the pig skin nor rat intestine and showed good biological photodynamic activity. Therefore, data obtained from the bioadhesive system indicate a potentially useful role as a platform for local hypericin delivery in PDT, suggesting it is worthy of in vivo evaluation. Copyright © 2017 Elsevier B.V. All rights reserved.

Amplifying the Red-Emission of Upconverting Nanoparticles for Biocompatible Clinically Used Prodrug-Induced Photodynamic Therapy

DOE PAGES

Punjabi, Amol; Wu, Xiang; Tokatli-Apollon, Amira; ...

2014-09-25

A class of biocompatible upconverting nanoparticles (UCNPs) with largely amplified red-emissions was developed. The optimal UCNP shows a high absolute upconversion quantum yield of 3.2% in red-emission, which is 15-fold stronger than the known optimal β-phase core/shell UCNPs. When conjugated to aminolevulinic acid, a clinically used photodynamic therapy (PDT) prodrug, significant PDT effect in tumor was demonstrated in a deep-tissue (>1.2 cm) setting in vivo at a biocompatible laser power density. Furthermore, we show that our UCNP–PDT system with NIR irradiation outperforms clinically used red light irradiation in a deep tumor setting in vivo. This study marks a major stepmore » forward in photodynamic therapy utilizing UCNPs to effectively access deep-set tumors.Lastly, it also provides an opportunity for the wide application of upconverting red radiation in photonics and biophotonics.« less

Amplifying the Red-Emission of Upconverting Nanoparticles for Biocompatible Clinically Used Prodrug-Induced Photodynamic Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Punjabi, Amol; Wu, Xiang; Tokatli-Apollon, Amira

A class of biocompatible upconverting nanoparticles (UCNPs) with largely amplified red-emissions was developed. The optimal UCNP shows a high absolute upconversion quantum yield of 3.2% in red-emission, which is 15-fold stronger than the known optimal β-phase core/shell UCNPs. When conjugated to aminolevulinic acid, a clinically used photodynamic therapy (PDT) prodrug, significant PDT effect in tumor was demonstrated in a deep-tissue (>1.2 cm) setting in vivo at a biocompatible laser power density. Furthermore, we show that our UCNP–PDT system with NIR irradiation outperforms clinically used red light irradiation in a deep tumor setting in vivo. This study marks a major stepmore » forward in photodynamic therapy utilizing UCNPs to effectively access deep-set tumors.Lastly, it also provides an opportunity for the wide application of upconverting red radiation in photonics and biophotonics.« less

Phthalocyanines And Their Sulfonated Derivatives As Photosensitizers In Photodynamic Therapy.

NASA Astrophysics Data System (ADS)

Riesz, Peter; Krishna, C. Murali

1988-02-01

Photodynamic therapy (PDT) of human tumors with hematoporphyrin derivative (HpD) has achieved encouraging results. However, HpD is a complex mixture whose composition varies in different preparations and with time of storage. The future promise of PDT for cancer treatment depends on the development of new chemically defined sensitizers which absorb more strongly than HpD in the 600-800 nm region. A shift to higher wavelengths is desirable since it allows increased light penetration in human tissues. In vivo, these sensitizers should be non-toxic, localize selectively in tumors and generate cytotoxic species upon illumination with a high quantum yield. These damaging species may be singlet oxygen (1O2) produced by the transfer of energy from the triplet state of the sensitizer to oxygen (Type II) or superoxide anion radicals formed by electron transfer to oxygen or substrate radicals generated by electron or hydrogen transfer directly from the sensitizer (Type I). The recent work of several groups indicating that phthalocyanines and their water soluble derivatives are promising candidates for PDT is reviewed. The photophysics, photochemistry, photosensitized killing of cultured mammalian cells and the use for in vivo photodynamic therapy of phthalocyanines is outlined. Our studies of the post-illumination photohemolysis of human red blood cells as a model system for membrane photomodification sensitized by phthalocyanine sulfonates are consistent with the predominant role of 1O2 as the damaging species.

Fluorescence intensity and bright spot analyses using a confocal microscope for photodynamic diagnosis of brain tumors.

PubMed

Yoneyama, Takeshi; Watanabe, Tetsuyo; Kagawa, Hiroyuki; Hayashi, Yutaka; Nakada, Mitsutoshi

2017-03-01

In photodynamic diagnosis using 5-aminolevulinic acid (5-ALA), discrimination between the tumor and normal tissue is very important for a precise resection. However, it is difficult to distinguish between infiltrating tumor and normal regions in the boundary area. In this study, fluorescent intensity and bright spot analyses using a confocal microscope is proposed for the precise discrimination between infiltrating tumor and normal regions. From the 5-ALA-resected brain tumor tissue, the red fluorescent and marginal regions were sliced for observation under a confocal microscope. Hematoxylin and eosin (H&E) staining were performed on serial slices of the same tissue. According to the pathological inspection of the H&E slides, the tumor and infiltrating and normal regions on confocal microscopy images were investigated. From the fluorescent intensity of the image pixels, a histogram of pixel number with the same fluorescent intensity was obtained. The fluorescent bright spot sizes and total number were compared between the marginal and normal regions. The fluorescence intensity distribution and average intensity in the tumor were different from those in the normal region. The probability of a difference from the dark enhanced the difference between the tumor and the normal region. The bright spot size and number in the infiltrating tumor were different from those in the normal region. Fluorescence intensity analysis is useful to distinguish a tumor region, and a bright spot analysis is useful to distinguish between infiltrating tumor and normal regions. These methods will be important for the precise resection or photodynamic therapy of brain tumors. Copyright © 2016 Elsevier B.V. All rights reserved.

Photodynamic therapy of advanced malignant tumors

NASA Astrophysics Data System (ADS)

Wang, Lian-xing; Dai, Lu-pin; Lu, Wen-qin

1993-03-01

Forty patients with advanced tumors were treated by photodynamic therapy (PDT) from May 1991 to August 1991 in our hospital with age ranges from 30 to 81 years old. The pathological diagnosis shows that 13 had tumors in the colon, 3 in the stomach, 2 in the oesophageal, 2 in the palatum, 1 in the cervix, and 19 others with malignant cancers of the skin. The histology was as follows: squamous cell in 20, adenocarcinoma in 19, melanocarcinoma in 1. By TNM classification there were no cases of T1, 5 cases of T2, and 35 cases of T2 - T3. All patients were stage IV. The overall effective rate was 85%, our experience is that the PDT is suitable for the patients with advanced tumor, especially those whose tumor recurrences are hard to treat after conventional treatment (surgery, radiotherapy, chemotherapy). The PDT appears to be a new and promising possibility to treat advanced tumors and to improve the patients' survival rates.

PHOTODYNAMIC THERAPY OF CANCER: AN UPDATE

PubMed Central

Agostinis, Patrizia; Berg, Kristian; Cengel, Keith A.; Foster, Thomas H.; Girotti, Albert W.; Gollnick, Sandra O.; Hahn, Stephen M.; Hamblin, Michael R.; Juzeniene, Asta; Kessel, David; Korbelik, Mladen; Moan, Johan; Mroz, Pawel; Nowis, Dominika; Piette, Jacques; Wilson, Brian C.; Golab, Jakub

2011-01-01

Photodynamic therapy (PDT) is a clinically approved, minimally invasive therapeutic procedure that can exert a selective cytotoxic activity toward malignant cells. The procedure involves administration of a photosensitizing agent followed by irradiation at a wavelength corresponding to an absorbance band of the sensitizer. In the presence of oxygen, a series of events lead to direct tumor cell death, damage to the microvasculature and induction of a local inflammatory reaction. Clinical studies revealed that PDT can be curative particularly in early-stage tumors. It can prolong survival in inoperable cancers and significantly improve quality of life. Minimal normal tissue toxicity, negligible systemic effects, greatly reduced long-term morbidity, lack of intrinsic or acquired resistance mechanisms, and excellent cosmetic as well as organ function-sparing effects of this treatment make it a valuable therapeutic option for combination treatments. With a number of recent technological improvements, PDT has the potential to become integrated into the mainstream of cancer treatment. PMID:21617154

Progress in the development of photodynamic-therapy-generated cancer vaccines

NASA Astrophysics Data System (ADS)

Korbelik, Mladen; Sun, Jinghai

2003-07-01

Upon giving an outline on vaccines in general, their history and priorities for future development, this paper gives a brief summary of the advances in the generation of cancer vaccines from the first attempts made over 100 years ago to those currently evaluted in clinical trials. This is followed by discussing hte intitial achievements in the investigation of cancer vaccines generated by photodynamic therapy (PDT). Recent contributions from our research to the understanding of how PDT-generated cancer vaccines work and their advantages compared to other types of cancer vaccines are discussed.

Spatially resolved frequency domain phosphorescence lifetime-based oxygen sensing for photodynamic therapy

NASA Astrophysics Data System (ADS)

Lai, Benjamin; Gurari, Mark; Wee, Wallace; Lilge, Lothar

2008-06-01

Photodynamic Therapy (PDT) is a minimally invasive treatment that uses a photosensitive drug into convert triplet state oxygen (3O2) to singlet oxygen (1O2) to destroy malignant tissue. A fiber-optic system based on frequency domain detection of phosphorescence quenching by 3O2 is described which optically measures the distribution of 3O2 in the treatment volume during PDT to permit adjustments of treatment parameters to improve outcome. A specially designed fiber optic probe containing phosphorescent sensors embedded along its length permit spatially resolved measurements. Each sensor is composed of a phosphorescent metalloporphyrin compound that emits a characteristic spectrum. Four candidate sensors with high absorption at the excitation wavelength of 405nm and emission in the 650nm to 700nm region are considered. The dependence of phosphorescence lifetime (τ) on 3O2 concentration is described by the linearized Stern-Volmer relationship as being inversely proportional. Determination of τ, and hence 3O2 concentration, is accomplished in the frequency domain by means of phase-modulation detection of the phosphorescence signal due to an amplitude modulated excitation. The τ's of each sensor are recovered by performing global non-linear least squares fit on the measured phase and modulation index over a range of frequencies and wavelengths. With the τ of each sensor known, the oxygen concentration at each sensor's location can be determined with the Stern-Volmer relationship.

Two-Step Irradiance Treatment Can Achieve Excellent Pain Control During Red Light 5-Aminolevulinic Acid Photodynamic Therapy for Actinic Keratoses.

PubMed

Paragh, Gyorgy; Zeitouni, Nathalie C

2018-03-01

To evaluate the ability of two-step irradiance to maintain pain control during red light 5-aminolevulinic acid (ALA) photodynamic therapy (PDT) for actinic keratoses (AK) and assess factors influencing pain. PDT provides excellent clinical and cosmetic results in the treatment AK and early basal cell carcinomas (BCC). Widespread use of PDT is limited, in part, by pain. A two-step irradiance method for PDT has previously been shown to significantly reduce PDT-associated pain during the treatment of BCC, but the ability of this method to limit pain during the treatment of AKs has not been reported. We performed a retrospective chart review to assess the level of pain during AK treatment by red light PDT (n = 99). Natural density filter was used to reduce the irradiance of the light source and initially 10 J/cm 2 dose was delivered at 35 mW/cm 2 and then, 65 J/cm 2 dose was delivered at 70 mW/cm 2 . Pain level was measured using a 10-point visual analog scale at three points during the procedure. Pain was low to moderate in most patients (mean ± standard error of the mean pain score: 2.35 ± 0.19). Higher pain was seen midprocedure versus at the beginning (p < 0.0001) and at the end (p = 0.003) of PDT. There was no significant difference in pain perception between genders and different treatment areas. Our results provide evidence that red light ALA PDT of AKs is very well tolerated with the two-step irradiance protocol.

[Physical treatment methods for acne. Light, laser, photodynamic therapy and peeling].

PubMed

Borelli, C; Korting, H C

2010-02-01

The medical treatment of acne is generally sufficient to meet the expectations of acne patients. However, in a number of situations additional therapeutic approaches may be advisable. There are a wide variety of useful physical methods. They range from electromagnetic waves, usually light, to peeling and manual therapy. Phototherapy of acne includes not just visible light but also laser and flash lamp therapy. The present review provides an overview on the evidence. Visible light, in particular blue light, provides an effective option for treatment of inflammatory acne. Photodynamic therapy also is efficacious; however, it should not be used because of an unfavorable risk-benefit ratio. UV treatment of acne is obsolete. Newer studies on the use of a variety of laser systems and flash lamps have demonstrated in part rewarding results.

Target cell specific antibody-based photosensitizers for photodynamic therapy

NASA Astrophysics Data System (ADS)

Rosenblum, Lauren T.; Mitsunaga, Makoto; Kakareka, John W.; Morgan, Nicole Y.; Pohida, Thomas J.; Choyke, Peter L.; Kobayashi, Hisataka

2011-03-01

In photodynamic therapy (PDT), localized monochromatic light is used to activate targeted photosensitizers (PS) to induce cellular damage through the generation of cytotoxic species such as singlet oxygen. While first-generation PS passively targeted malignancies, a variety of targeting mechanisms have since been studied, including specifically activatable agents. Antibody internalization has previously been employed as a fluorescence activation system and could potentially enable similar activation of PS. TAMRA, Rhodamine-B and Rhodamine-6G were conjugated to trastuzumab (brand name Herceptin), a humanized monoclonal antibody with specificity for the human epidermal growth factor receptor 2 (HER2), to create quenched PS (Tra-TAM, Tra-RhoB, and Tra-Rho6G). Specific PDT with Tra-TAM and Tra-Rho6G, which formed covalently bound H-dimers, was demonstrated in HER2+ cells: Minimal cell death (<6%) was observed in all treatments of the HER2- cell line (BALB/3T3) and in treatments the HER2+ cell line (3T3/HER2) with light or trastuzumab only. There was significant light-induced cell death in HER2 expressing cells using Tra-TAM (3% dead without light, 20% at 50 J/cm2, 46% at 100 J/cm2) and Tra-Rho6G (5% dead without light, 22% at 50 J/cm2, 46% at 100 J/cm2). No efficacy was observed in treatment with Tra-RhoB, which was also non-specifically taken up by BALB/3T3 cells and which had weaker PS-antibody interactions (as demonstrated by visualization of protein and fluorescence on SDS-PAGE).

Clinical potential for vitamin D as a neoadjuvant for photodynamic therapy of nonmelanoma skin cancer

NASA Astrophysics Data System (ADS)

Maytin, Edward V.; Anand, Sanjay; Rollakanti, Kishore

2015-03-01

Nonmelanoma skin cancer (NMSC), comprising basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), is the most common form of human cancer worldwide. Effective therapies include surgical excision, cryotherapy, and ionizing radiation, but all of these cause scarring. ALA-based PDT is a non-scarring modality used routinely for NMSC in Europe but not in the USA, primarily due to lingering uncertainties about efficacy. We have identified three agents (methotrexate, 5-fluorouracil, and vitamin D) that can be used as neoadjuvants, i.e., can be given as a pretreatment prior to ALA-PDT, to improve the efficacy of tumor killing in mouse models of NMSC. Vitamin D (VD3) is the most recent neoadjuvant on this list. In this presentation we make the case that VD3 may be superior to the other agents to improve results of ALA-PDT skin cancer treatment. The active form of VD3 (calcitriol) is available topically as a pharmaceutical grade cream or ointment (FDA-approved for psoriasis), and works well for boosting ALA-PDT tumor treatment in mouse models. For deep tumors not reachable by a topical route, calcitriol can be given systemically and is very effective, but carries a risk of causing hypercalcemia as a side effect. To circumvent this risk, we have conducted experiments with the natural dietary form of VD3 (cholecalciferol), and showed that this improves ALA-PDT efficacy almost to the same extent as calcitriol. Because cholecalciferol does not increase serum calcium levels, this represents a potentially extremely safe approach. Data in mouse models of BCC and SCC will be presented.

Photodynamic hyperthermal chemotherapy with indocyanine green: a novel cancer therapy for 16 cases of malignant soft tissue sarcoma

PubMed Central

Onoyama, Masaki; Tsuka, Takeshi; Imagawa, Tomohiro; Osaki, Tomohiro; Minami, Saburo; Azuma, Kazuo; Kawashima, Kazuhiko; Ishi, Hiroshi; Takayama, Takahiro; Ogawa, Nobuhiko

2014-01-01

Sixteen cases of malignant soft tissue sarcoma (STS; 10 canines and six felines) were treated with a novel triple therapy that combined photodynamic therapy, hyperthermia using indocyanine green with a broadband light source, and local chemotherapy after surgical tumor resection. This triple therapy was called photodynamic hyperthermal chemotherapy (PHCT). In all cases, the surgical margin was insufficient. In one feline case, PHCT was performed without surgical resection. PHCT was performed over an interval of 1 to 2 weeks and was repeated three to 21 times. No severe side effects, including severe skin burns, necrosis, or skin suture rupture, were observed in any of the animals. No disease recurrence was observed in seven out of 10 (70.0%) dogs and three out of six (50.0%) cats over the follow-up periods ranging from 238 to 1901 days. These results suggest that PHCT decreases the risk of STS recurrence. PHCT should therefore be considered an adjuvant therapy for treating companion animals with STS in veterinary medicine. PMID:24136207

Cancer treatment by photodynamic therapy combined with NK-cell-line-based adoptive immunotherapy

NASA Astrophysics Data System (ADS)

Korbelik, Mladen; Sun, Jinghai

1998-05-01

Treatment of solid cancers by photodynamic therapy (PDT) triggers a strong acute inflammatory reaction localized to the illuminated malignant tissue. This event is regulated by a massive release of various potent mediators which have a profound effect not only on local host cell populations, but also attract different types of immune cells to the treated tumor. Phagocytosis of PDT-damaged cancerous cells by antigen presenting cells, such as activated tumor associated macrophages, enables the recognition of even poorly immunogenic tumors by specific immune effector cells and the generation of immune memory populations. Because of its inflammatory/immune character, PDT is exceptionally responsive to adjuvant treatments with various types of immunotherapy. Combining PDT with immuneactivators, such as cytokines or other specific or non-specific immune agents, rendered marked improvements in tumor cures with various cancer models. Another clinically attractive strategy is adoptive immunotherapy, and the prospects of its use in conjunction with PDT are outlined.

Uniform irradiation of irregularly shaped cavities for photodynamic therapy.

PubMed

Rem, A I; van Gemert, M J; van der Meulen, F W; Gijsbers, G H; Beek, J F

1997-03-01

It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow 'integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a cubical box, a sphere, a cylinder and a 'bottle-neck' geometry have been investigated experimentally and the results have been compared with computed light distributions obtained using the 'radiosity method'. A high reflection coefficient of the mould and the best uniform direct irradiance possible on the inside of the mould were found to be important determinants for achieving a uniform light distribution.

Lutetium(III) acetate phthalocyanines for photodynamic therapy applications: Synthesis and photophysicochemical properties.

PubMed

Mantareva, Vanya; Durmuş, Mahmut; Aliosman, Meliha; Stoineva, Ivanka; Angelov, Ivan

2016-06-01

The development of new water-soluble photosensitizers for photodynamic therapy (PDT) applications is a very active research topic. Efforts have been made to obtain the far-red absorbing phthalocyanine complexes with molecular design that facilitates the uptake and selectivity for a high PDT efficiency. The monomolecular lutetium(III) acetate phthalocyanines (LuPcs) substituted with methylpyridyloxy groups at non-peripheral (5) and peripheral (6) positions were synthesized by following the modification of the well-known synthetical routes. The photo-physicochemical properties of the both quaternized LuPcs were evaluated by the steady-state and time-resolved spectroscopy. The photochemical technique was applied to study the generation of the singlet oxygen. Two water-soluble and cationic LuPcs were synthesized and chemically characterized. The photo-physicochemical properties of absorption (675 and 685nm) and the red shifted fluorescence (704 and 721nm) as well as the fluorescence lifetimes (2.24 and 3.27ns) were studied. The promising values of singlet oxygen quantum yields (0.32 for 5 and 0.35 for 6) were determined. Lutetium(III) acetate phthalocyanine complexes were synthesized and evaluated with physicochemical properties suitable for future photodynamic therapy applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Device for fluorescent control and photodynamic therapy of age-related macula degeneration

NASA Astrophysics Data System (ADS)

Loschenov, Victor B.; Meerovich, Gennadii A.; Budzinskaya, M. V.; Ermakova, N. A.; Shevchik, S. A.; Kharnas, Sergey S.

2004-07-01

Age-related macula degeneration (AMD) is a wide spread disease the appearance of which leads to poor eyesight and blindness. A method of treatment is not determined until today. Traditional methods, such as laser coagulation and surgical operations are rather traumatic for eye and often bring to complications. That's why recently a photodynamic method of AMD treatment is studied. Based on photodynamic occlusion of choroidal neovascularization (CNV) with minimal injury to overlying neurosensory retina what increases the efficiency.

Wavelength-dependent in-vitro and in-vivo photodynamic effects after sensitization with 5-aminolevulinic acid induced protoporphyrin IX

NASA Astrophysics Data System (ADS)

Szeimies, Rolf-Markus; Abels, Christoph; Fritsch, Clemens; Steinbach, Pia; Baeumler, Wolfgang; Messmann, Helmut; Goetz, Alwin E.; Goerz, Guenter; Landthaler, Michael

1996-01-01

Photodynamic therapy (PDT) with topically applied 5-aminolevulinic acid (ALA) is of growing interest, in particular in dermatology. Due to the fact that PDT with intravenously administered Photofrin is the only clinically approved sensitizer so far and is performed at a wavelength of 630 nm, this wavelength is also used in most experimental and clinical trials with ALA. In this study influence of irradiation with coherent light from a tunable dye laser at different wavelengths ranging from 625 to 649 nm was investigated. In in vitro experiments HaCaT immortalized human keratinocytes were sensitized with 30 (mu) g/ml ALA for 24 hrs. By determination of cell viability with the MTT test, best cell-killing effects were observed following irradiation at 635 nm. In an in vivo setting using an amelanotic melanoma (A-Mel-3) grown subcutaneously in Syrian Golden hamsters, these results were confirmed: tumor growth determined by measuring tumor volume increase after 28 days was less pronounced in animals treated with 100 mg/kg ALA i.v. and irradiated 2.5 hrs. later at 635 nm, as compared to animals receiving an equal dose and irradiated at 630 nm. This observation in vitro is probably due to large amounts of photosensitizing protoporphyrin IX (PP) localized in cell membranes which is visualized by confocal laser scanning microscopy (CLSM) and determined by HPLC analysis. These results suggest that in ALA-PDT when a coherent light source is used probably better results are achieved irradiating at 635 nm.

Two-photon excitation of porphyrin-functionalized porous silicon nanoparticles for photodynamic therapy.

PubMed

Secret, Emilie; Maynadier, Marie; Gallud, Audrey; Chaix, Arnaud; Bouffard, Elise; Gary-Bobo, Magali; Marcotte, Nathalie; Mongin, Olivier; El Cheikh, Khaled; Hugues, Vincent; Auffan, Mélanie; Frochot, Céline; Morère, Alain; Maillard, Philippe; Blanchard-Desce, Mireille; Sailor, Michael J; Garcia, Marcel; Durand, Jean-Olivier; Cunin, Frédérique

2014-12-03

Porous silicon nanoparticles (pSiNPs) act as a sensitizer for the 2-photon excitation of a pendant porphyrin using NIR laser light, for imaging and photodynamic therapy. Mannose-functionalized pSiNPs can be vectorized to MCF-7 human breast cancer cells through a mannose receptor-mediated endocytosis mechanism to provide a 3-fold enhancement of the 2-photon PDT effect. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sonodynamic therapy using water-dispersed TiO2-polyethylene glycol compound on glioma cells: comparison of cytotoxic mechanism with photodynamic therapy.

PubMed

Yamaguchi, Shigeru; Kobayashi, Hiroyuki; Narita, Takuhito; Kanehira, Koki; Sonezaki, Shuji; Kudo, Nobuki; Kubota, Yoshinobu; Terasaka, Shunsuke; Houkin, Kiyohiro

2011-09-01

Sonodynamic therapy is expected to be a novel therapeutic strategy for malignant gliomas. The titanium dioxide (TiO(2)) nanoparticle, a photosensitizer, can be activated by ultrasound. In this study, by using water-dispersed TiO(2) nanoparticles, an in vitro comparison was made between the photodynamic and sonodynamic damages on U251 human glioblastoma cell lines. Water-dispersed TiO(2) nanoparticles were constructed by the adsorption of chemically modified polyethylene glycole (PEG) on the TiO(2) surface (TiO(2)/PEG). To evaluate cytotoxicity, U251 monolayer cells were incubated in culture medium including 100 μg/ml of TiO(2)/PEG for 3h and subsequently irradiated by ultraviolet light (5.0 mW/cm(2)) or 1.0MHz ultrasound (1.0 W/cm(2)). Cell survival was estimated by MTT assay 24h after irradiation. In the presence of TiO(2)/PEG, the photodynamic cytotoxic effect was not observed after 20 min of an ultraviolet light exposure, while the sonodynamic cytotoxicity effect was almost proportional to the time of sonication. In addition, photodynamic cytotoxicity of TiO(2)/PEG was almost completely inhibited by radical scavenger, while suppression of the sonodynamic cytotoxic effect was not significant. Results of various fluorescent stains showed that ultrasound-treated cells lost their viability immediately after irradiation, and cell membranes were especially damaged in comparison with ultraviolet-treated cells. These findings showed a potential application of TiO(2)/PEG to sonodynamic therapy as a new treatment of malignant gliomas and suggested that the mechanism of TiO(2)/PEG mediated sonodynamic cytotoxicity differs from that of photodynamic cytotoxicity. Copyright © 2011 Elsevier B.V. All rights reserved.

GIS-based accident location and analysis system (GIS-ALAS) : project report : phase I

DOT National Transportation Integrated Search

1998-04-06

This report summarizes progress made in Phase I of the geographic information system (GIS) based Accident Location and Analysis System (GIS-ALAS). The GIS-ALAS project builds on PC-ALAS, a locationally-referenced highway crash database query system d...

Intravenous Single-Dose Toxicity of Redaporfin-Based Photodynamic Therapy in Rodents

PubMed Central

Rocha, Luis B.; Schaberle, Fábio; Dąbrowski, Janusz M.; Simões, Sérgio; Arnaut, Luis G.

2015-01-01

We assessed the tolerability and safety in rodents of a single intravenous (i.v.) dose of redaporfin, a novel photosensitizer for Photodynamic Therapy (PDT) of cancer. Two approaches were used to evaluate acute toxicity: (i) a dose escalation study in BALB/c mice to evaluate the maximum tolerated dose of redaporfin; and (ii) a safety toxicology study in Wistar rats, of a single dose of redaporfin, with or without illumination, to evaluate possible signs of systemic toxicity. Redaporfin formulation was well tolerated by mice, with no signs of adverse reactions up to 75 mg/kg. In rats, there were no relevant changes, except for a significant, but transient, increase in the blood serum markers for hepatic function and muscle integrity, and also on neutrophil counts, observed after the application of light. The overall results showed that redaporfin-PDT is very well tolerated. No abnormalities were observed, including reactions at the injection site or skin phototoxicity, although the animals were maintained in normal indoor lighting. Redaporfin also showed a high efficacy in the treatment of male BALB/c mice with subcutaneously implanted colon (CT26) tumours. Vascular-PDT with 1.5 mg/kg redaporfin and a light dose of 74 J/cm2 led to the complete tumour regression in 83% of the mice. PMID:26670231

Resistance of Nonmelanoma Skin Cancer to Nonsurgical Treatments. Part II: Photodynamic Therapy, Vismodegib, Cetuximab, Intralesional Methotrexate, and Radiotherapy.

PubMed

Gracia-Cazaña, T; Salazar, N; Zamarrón, A; Mascaraque, M; Lucena, S R; Juarranz, Á

2016-11-01

A wide range of treatments is now available for nonmelanoma skin cancer, including 5-fluorouracil, ingenol mebutate, imiquimod, diclofenac, photodynamic therapy, methotrexate, cetuximab, vismodegib, and radiotherapy. All are associated with high clinical and histologic response rates. However, some tumors do not respond due to resistance, which may be primary or acquired. Study of the resistance processes is a broad area of research that aims to increase our understanding of the nature of each tumor and the biologic features that make it resistant, as well as to facilitate the design of new therapies directed against these tumors. In this second article, having covered the topical treatments of nonmelanoma skin cancer, we review resistance to other nonsurgical treatments, such as monoclonal antibodies against basal and squamous cell carcinomas, intralesional chemotherapy, photodynamic therapy, and radiotherapy. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

Photodynamic therapy for port wine stains

NASA Astrophysics Data System (ADS)

Li, Junheng

1998-08-01

Therapies for port wine stains including conventional laser irradiation usually cause unacceptable scarring or obtain poor effect. Pulsed dye laser has better approach, but only few patients obtain complete fading after multiple laser treatment. Because port wine stain is a congenital vasculopathy consisting of an abnormal network of capillaries in the upper dermis with an overlying normal epidermis and the researchers found that tumor blood vessels were occluded accompanying the necrosis of the tumor after PDT. It is though to be the effect primarily by thrombus formation in vessels and shut down of the blood supply to the tumor as well as direct tumor cells kill. The author and his colleagues started a series of animal and clinical studies since 1991 about photodynamic therapy for port wine stains and they established the method of PDT for PWS. An experimental study showed that Hpd appeared rapidly within the human vascular endothelial cells in culture fluid. Animal study using chicken combs as PWS models treated by PDT revealed the possibility of selective destruction of the malformative vasculature in PWS. The clinical studies of over 1700 cases proved that PWS can be cured without scar formation by PDT because there is no thermal effect involved. No relapse was found within a maximum follow-up of seven years. The differences and mechanism between the treatments of PDT and conventional lasers are discussed.

Phage Therapy and Photodynamic Therapy: Low Environmental Impact Approaches to Inactivate Microorganisms in Fish Farming Plants

PubMed Central

Almeida, Adelaide; Cunha, Ângela; Gomes, Newton C.M.; Alves, Eliana; Costa, Liliana; Faustino, Maria A.F.

2009-01-01

Owing to the increasing importance of aquaculture to compensate for the progressive worldwide reduction of natural fish and to the fact that several fish farming plants often suffer from heavy financial losses due to the development of infections caused by microbial pathogens, including multidrug resistant bacteria, more environmentally-friendly strategies to control fish infections are urgently needed to make the aquaculture industry more sustainable. The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy. PMID:19841715

Optoacoustic imaging of tissue blanching during photodynamic therapy of esophageal cancer

NASA Astrophysics Data System (ADS)

Jacques, Steven L.; Viator, John A.; Paltauf, Guenther

2000-05-01

Esophageal cancer patients often present a highly inflamed esophagus at the time of treatment by photodynamic therapy. Immediately after treatment, the inflamed vessels have been shut down and the esophagus presents a white surface. Optoacoustic imaging via an optical fiber device can provide a depth profile of the blanching of inflammation. Such a profile may be an indicator of the depth of treatment achieved by the PDT. Our progress toward developing this diagnostic for use in our clinical PDT treatments of esophageal cancer patients is presented.

Verteporfin: a milestone in opthalmology and photodynamic therapy.

PubMed

Brown, S B; Mellish, K J

2001-02-01

During the past year, a photosensitiser named benzoporphyrin derivative (BPD) has been approved in 26 countries under the generic name verteporfin (Visudynetrade mark, Novartis), for the treatment of patients with a certain type of the wet form of age-related macular degeneration (AMD) by photodynamic therapy (PDT). AMD is the leading cause of blindness in the developed world, with approximately half a million new cases of the wet form per year. The approval of Visudynetrade mark therapy represents a major milestone in ophthalmology since AMD was previously untreatable by any modality which would preserve existing vision. It was also a milestone in the development of PDT, not only because it represented the first breakthrough in the use of PDT to treat an otherwise untreatable condition, but also because it represented the first mass market for a PDT treatment where prospects of a substantial financial return on many years of investment appear to be likely. In this article, we look at the background to the development of BPD, primarily for its use in AMD, but also in other applications.

TREATMENT OF EXUDATIVE AGE-RELATED MACULAR DEGENERATION WITH RANIBIZUMAB COMBINED WITH KETOROLAC EYEDROPS OR PHOTODYNAMIC THERAPY.

PubMed

Semeraro, Francesco; Russo, Andrea; Delcassi, Luisa; Romano, Mario R; Rinaldi, Michele; Chiosi, Flavia; Costagliola, Ciro

2015-08-01

To evaluate whether ketorolac eyedrops plus intravitreal ranibizumab (IVR) or verteporfin photodynamic therapy plus IVR provides additional benefit over IVR monotherapy for treatment of choroidal neovascularization in age-related macular degeneration. This was a prospective, randomized, pilot study in 75 patients with naive choroidal neovascularization. Patients were randomized 1:1:1 into 3 groups: ranibizumab monotherapy (RM), ranibizumab plus ketorolac, or ranibizumab plus loading-phase reduced-fluence verteporfin photodynamic therapy (RV) groups. At 12 months, all groups showed significant improvement in both best-corrected visual acuity and central retinal thickness. The mean best-corrected visual acuity change from baseline to 12 months was -0.14 ± 0.52 logMAR (20/73 ± 20/29), -0.25 ± 0.60 logMAR (20/46 ± 20/27), and -0.10 ± 0.30 (20/97 ± 20/40) logMAR in RM, ranibizumab plus ketorolac, and RV groups, respectively. The mean central retinal thickness change from baseline to 12 months was -125 ± 15 μm, -141 ± 21 μm, and -130 ± 15 μm in RM, ranibizumab plus ketorolac, and RV groups, respectively. Both ranibizumab plus ketorolac and RV groups required fewer IVR treatments than RM. Compared with RM and ranibizumab plus verteporfin photodynamic therapy, the combination of 0.45% ketorolac eyedrops 3 times a day and ranibizumab in patients with choroidal neovascularization provided superior best-corrected visual acuity and central retinal thickness outcomes. Both combination regimens required fewer IVR injections than RM during the 12-month follow-up period.

Zinc phthalocyanine-loaded PLGA biodegradable nanoparticles for photodynamic therapy in tumor-bearing mice.

PubMed

Fadel, Maha; Kassab, Kawser; Fadeel, Doa Abdel

2010-03-01

Nanoparticles formulated from the biodegradable copolymer poly(lactic-coglycolic acid) (PLGA) were investigated as a drug delivery system to enhance tissue uptake, permeation, and targeting of zinc(II) phthalocyanine (ZnPc) for photodynamic therapy. Three ZnPc nanoparticle formulations were prepared using a solvent emulsion evaporation method and the influence of sonication time on nanoparticle shape, encapsulation and size distribution, in vitro release, and in vivo photodynamic efficiency in tumor-bearing mice were studied. Sonication time did not affect the process yield or encapsulation efficiency, but did affect significantly the particle size. Sonication for 20 min reduced the mean particle size to 374.3 nm and the in vitro release studies demonstrated a controlled release profile of ZnPc. Tumor-bearing mice injected with ZnPc nanoparticles exhibited significantly smaller mean tumor volume, increased tumor growth delay and longer survival compared with the control group and the group injected with free ZnPc during the time course of the experiment. Histopathological examination of tumor from animals treated with PLGA ZnPc showed regression of tumor cells, in contrast to those obtained from animals treated with free ZnPc. The results indicate that ZnPc encapsulated in PLGA nanoparticles is a successful delivery system for improving photodynamic activity in the target tissue.

Stimuli-responsive magnetic nanoparticles for tumor-targeted bimodal imaging and photodynamic/hyperthermia combination therapy

NASA Astrophysics Data System (ADS)

Kim, Kyoung Sub; Kim, Jiyoung; Lee, Joo Young; Matsuda, Shofu; Hideshima, Sho; Mori, Yasurou; Osaka, Tetsuya; Na, Kun

2016-06-01

Despite magnetic nanoparticles having shown great potential in cancer treatment, tremendous challenges related to diagnostic sensitivity and treatment efficacy for clinical application remain. Herein, we designed optimized multifunctional magnetite nanoparticles (AHP@MNPs), composed of Fe3O4 nanoparticles and photosensitizer conjugated hyaluronic acid (AHP), to achieve enhanced tumor diagnosis and therapy. Fe3O4 nanoparticles (MNPs) were synthesized by a facile hydrolysis method. MNPs have higher biocompatibility, controllable particle sizes, and desirable magnetic properties. The fabricated AHP@MNPs have enhanced water solubility (average size: 108.13 +/- 1.08 nm), heat generation properties, and singlet oxygen generation properties upon magnetic and laser irradiation. The AHP@MNPs can target tumors via CD44 receptor-mediated endocytosis, which have enhanced tumor therapeutic effects through photodynamic/hyperthermia-combined treatment without any drugs. We successfully detected tumors implanted in mice via magnetic resonance imaging and optical imaging. Furthermore, we demonstrated the photodynamic/hyperthermia-combined therapeutic efficacy of AHP@MNPs with synergistically enhanced efficacy against cancer.Despite magnetic nanoparticles having shown great potential in cancer treatment, tremendous challenges related to diagnostic sensitivity and treatment efficacy for clinical application remain. Herein, we designed optimized multifunctional magnetite nanoparticles (AHP@MNPs), composed of Fe3O4 nanoparticles and photosensitizer conjugated hyaluronic acid (AHP), to achieve enhanced tumor diagnosis and therapy. Fe3O4 nanoparticles (MNPs) were synthesized by a facile hydrolysis method. MNPs have higher biocompatibility, controllable particle sizes, and desirable magnetic properties. The fabricated AHP@MNPs have enhanced water solubility (average size: 108.13 +/- 1.08 nm), heat generation properties, and singlet oxygen generation properties upon magnetic and laser

Magnetic iron oxide modified pyropheophorbide-a fluorescence nanoparticles as photosensitizers for photodynamic therapy against ovarian cancer (SKOV-3) cells.

PubMed

Tan, Guanghui; Li, Wenting; Cheng, Jianjun; Wang, Zhiqiang; Wei, Shuquan; Jin, Yingxue; Guo, Changhong; Qu, Fengyu

2016-11-30

Magnetic iron oxide modified pyropheophorbide-a fluorescence nanoparticles, Fe 3 O 4 @SiO 2 @APTES@PPa (FSAP), were designed as magnetically targeted photodynamic antineoplastic agents and prepared through continuous covalent chemical modification on the surface of Fe 3 O 4 nanoparticles. The properties of the intermediates and the final product were comprehensively characterized by transmission electron microscopy, powder X-ray diffraction analysis, Fourier transform infrared spectroscopy, vibrating sample magnetometry, zeta potential measurement, ultraviolet-visible absorption spectroscopy, fluorescence emission spectroscopy, and thermogravimetric analysis. In this work, we demonstrated the in vitro photodynamic therapy (PDT) of FSAP against ovarian cancer (SKOV-3) cells, which indicated that FSAP could be taken up successfully and showed low dark toxicity without irradiation, but remarkable phototoxicity after irradiation. Meanwhile, FSAP had showed good biocompatibility and low dark toxicity against normal cells in the biological experiments on mouse normal fibroblast cell lines (L929 cells). In addition, in the photochemical process of FSAP mediated photodynamic therapy, the Type-II photo-oxygenation process (generated singlet oxygen) played an important role in the induction of cell damage.

Photodynamic therapy using chlorophyll-a in the treatment of acne vulgaris: a randomized, single-blind, split-face study.

PubMed

Song, Byong Han; Lee, Dong Hun; Kim, Byung Chul; Ku, Sang Hyeon; Park, Eun Joo; Kwon, In Ho; Kim, Kwang Ho; Kim, Kwang Joong

2014-10-01

Chlorophyll-a is a novel photosensitizer recently tested for the treatment of acne vulgaris. We sought to evaluate the clinical efficacy and safety of chlorophyll-a photodynamic therapy used for acne treatment. Subjects with acne on both sides of the face were included. Eight treatment sessions were performed over a 4-week duration. Half of the face was irradiated using a blue and red light-emitting diode after topical application of chlorophyll-lipoid complex. The other half underwent only light-emitting diode phototherapy. The lesion counts and acne severity were assessed by a blinded examiner. Sebum secretion, safety, and histologic changes were also evaluated. In total, 24 subjects completed the study. Facial acne improved on both treated sides. On the chlorophyll-a photodynamic therapy-treated side, there were significant reductions in acne lesion counts, acne severity grades, and sebum levels compared with the side treated with light-emitting diode phototherapy alone. The side effects were tolerable in all the cases. All the subjects were of Asian descent with darker skin types, which may limit the generalizability of the study. A chlorophyll-a arm alone is absent, as is a no-treatment arm. We suggest that chlorophyll-a photodynamic therapy for the treatment of acne vulgaris can be effective and safe with minimal side effects. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Virus Capsids as Targeted Nanoscale Delivery Vessels of Photoactive Compounds for Site-Specific Photodynamic Therapy

NASA Astrophysics Data System (ADS)

Cohen, Brian A.

The research presented in this work details the use of a viral capsid as an addressable delivery vessel of photoactive compounds for use in photodynamic therapy. Photodynamic therapy is a treatment that involves the interaction of light with a photosensitizing molecule to create singlet oxygen, a reactive oxygen species. Overproduction of singlet oxygen in cells can cause oxidative damage leading to cytotoxicity and eventually cell death. Challenges with the current generation of FDA-approved photosensitizers for photodynamic therapy primarily stem from their lack of tissue specificity. This work describes the packaging of photoactive cationic porphyrins inside the MS2 bacteriophage capsid, followed by external modification of the capsid with cancer cell-targeting G-quadruplex DNA aptamers to generate a tumor-specific photosensitizing agent. First, a cationic porphyrin is loaded into the capsids via nucleotide-driven packaging, a process that involves charge interaction between the porphyrin and the RNA inside the capsid. Results show that over 250 porphyrin molecules associate with the RNA within each MS2 capsid. Removal of RNA from the capsid severely inhibits the packaging of the cationic porphyrins. Porphyrin-virus constructs were then shown to photogenerate singlet oxygen, and cytotoxicity in non-targeted photodynamic treatment experiments. Next, each porphyrin-loaded capsid is externally modified with approximately 60 targeting DNA aptamers by employing a heterobifunctional crosslinking agent. The targeting aptamer is known to bind the protein nucleolin, a ubiquitous protein that is overexpressed on the cell surface by many cancer cell types. MCF-7 human breast carcinoma cells and MCF-10A human mammary epithelial cells were selected as an in vitro model for breast cancer and normal tissue, respectively. Fluorescently tagged virus-aptamer constructs are shown to selectively target MCF-7 cells versus MCF-10A cells. Finally, results are shown in which porphyrin

Nanoscale metal-organic frameworks for photodynamic therapy and cancer immunotherapy (Conference Presentation)

NASA Astrophysics Data System (ADS)

Lin, Wenbin

2017-02-01

Photodynamic therapy (PDT) is an effective anticancer procedure that relies on tumor localization of a photosensitizer followed by light activation to generate cytotoxic reactive oxygen species. We recently reported the rational design of a Hf-porphyrin nanoscale metal-organic framework, DBP-UiO, as an exceptionally effective photosensitizer for PDT of resistant head and neck cancer. DBP-UiO efficiently generates singlet oxygen owing to site isolation of porphyrin ligands, enhanced intersystem crossing by heavy Hf centers, and facile singlet oxygen diffusion through porous DBP-UiO nanoplates. Consequently, DBP-UiO displayed greatly enhanced PDT efficacy both in vitro and in vivo, leading to complete tumor eradication in half of the mice receiving a single DBP-UiO dose and a single light exposure. The photophysical properties of DBP-UiO are however not optimum with the lowest energy absorption at 634 nm and a relatively small extinction coefficient of 2200 M-1·cm-1. We recently designed a chlorin-based NMOF, DBC-UiO, with much improved photophysical properties and PDT efficacy in two colon cancer mouse models. Reduction of the DBP ligands in DBP-UiO to the DBC ligands in DBC-UiO led to a 13 nm red-shift and an 11-fold extinction coefficient increase of the lowest energy Q-band. While inheriting the crystallinity, stability, porosity, and nanoplate morphology of DBP-UiO, DBC-UiO sensitizes more efficient singlet oxygen generation and exhibits much enhanced photodynamic therapy (PDT) efficacy on two colon cancer mouse models as a result of its improved photophysical properties. Both apoptosis and immunogenic cell death contributed to cancer cell-killing in DBC-UiO induced PDT. Our work has thus demonstrated that NMOFs represent a new class of highly potent PDT agents and hold great promise in treating resistant cancers in the clinic.

Phosphorus dendrimers and photodynamic therapy. Spectroscopic studies on two dendrimer-photosensitizer complexes: Cationic phosphorus dendrimer with rose bengal and anionic phosphorus dendrimer with methylene blue.

PubMed

Dabrzalska, Monika; Zablocka, Maria; Mignani, Serge; Majoral, Jean Pierre; Klajnert-Maculewicz, Barbara

2015-08-15

Dendrimers due to their unique architecture may play an important role in drug delivery systems including chemotherapy, gene therapy and recently, photodynamic therapy as well. We investigated two dendrimer-photosensitizer systems in context of potential use of these systems in photodynamic therapy. The mixtures of an anionic phosphorus dendrimer of the second generation and methylene blue were studied by UV-vis spectroscopy while that of a cationic phosphorus dendrimer (third generation) and rose bengal were investigated by spectrofluorimetric methods. Spectroscopic analysis of these two systems revealed the formation of dendrimer-photosensitizer complexes via electrostatic interactions as well as π stacking. The stoichiometry of the rose bengal-cationic dendrimer complex was estimated to be 7:1 and 9:1 for the methylene blue-anionic dendrimer complex. The results suggest that these polyanionic or polycationic phosphorus dendrimers can be promising candidates as carriers in photodynamic therapy. Copyright © 2015 Elsevier B.V. All rights reserved.

Photodynamic therapy of cancer with the photosensitizer PHOTOGEM

NASA Astrophysics Data System (ADS)

Sokolov, Victor V.; Chissov, Valery I.; Filonenko, E. V.; Sukhin, Garry M.; Yakubovskaya, Raisa I.; Belous, T. A.; Zharkova, Natalia N.; Kozlov, Dmitrij N.; Smirnov, V. V.

1995-01-01

The first clinical trials of photodynamic therapy (PDT) in Russia were started in P. A. Hertzen Moscow Research Oncology Institute in October of 1992. Up to now, 61 patients with primary or recurrent malignant tumors of the larynx (3), trachea (1), bronchus (11), nose (1), mouth (3), esophagus (12), vagina and uterine cervix (3), bladder (2), skin (6), and cutaneous and subcutaneous metastases of breast cancer and melanomas (6) have been treated by PDT with the photosensitizer Photogem. At least partial tumor response was observed in all of the cases, but complete remission indicating no evident tumors has been reached in 51% of the cases. Among 29 patients with early and first stage cancer 14 patients had multifocal tumors. Complete remission of tumors in this group reached 86%.

Novel Methods to Incorporate Photosensitizers Into Nanocarriers for Cancer Treatment by Photodynamic Therapy

PubMed Central

Wang, Shouyan; Fan, Wenzhe; Kim, Gwangseong; Hah, Hoe Jin; Lee, Yong-Eun Koo; Kopelman, Raoul; Ethirajan, Manivannan; Gupta, Anurag; Goswami, Lalit N.; Pera, Paula; Morgan, Janet; Pandey, Ravindra K.

2013-01-01

Objective A hydrophobic photosensitizer, 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a (HPPH), was loaded into nontoxic biodegradable amine functionalized polyacrylamide (AFPAA) nanoparticles using three different methods (encapsulation, conjugation, and post-loading), forming a stable aqueous dispersion. Each formulation was characterized for physicochemical properties as well as for photodynamic performance so as to determine the most effective nanocarrier formulation containing HPPH for photodynamic therapy (PDT). Materials and Methods HPPH or HPPH-linked acrylamide was added into monomer mixture and polymerized in a microemulsion for encapsulation and conjugation, respectively. For post-loading, HPPH was added to an aqueous suspension of pre-formed nanoparticles. Those nanoparticles were tested for optical characteristics, dye loading, dye leaching, particle size, singlet oxygen production, dark toxicity, in vitro photodynamic cell killing, whole body fluorescence imaging and in vivo PDT. Results HPPH was successfully encapsulated, conjugated or post-loaded into the AFPAA nanoparticles. The resultant nanoparticles were spherical with a mean diameter of 29 ± 3 nm. The HPPH remained intact after entrapment and the HPPH leaching out of nanoparticles was negligible for all three formulations. The highest singlet oxygen production was achieved by the post-loaded formulation, which caused the highest phototoxicity in in vitro assays. No dark toxicity was observed. Post-loaded HPPH AFPAA nanoparticles were localized to tumors in a mouse colon carcinoma model, enabling fluorescence imaging, and producing a similar photodynamic tumor response to that of free HPPH in equivalent dose. Conclusions Post-loading is the promising method for loading nanoparticles with hydrophobic photosensitizers to achieve effective in vitro and in vivo PDT. Lasers Surg. Med. 43:686–695, 2011. PMID:22057496

5-Aminolevulinic Acid-Squalene Nanoassemblies for Tumor Photodetection and Therapy: In Vitro Studies

NASA Astrophysics Data System (ADS)

Babič, Andrej; Herceg, V.; Bastien, E.; Lassalle, H.-P.; Bezdetnaya, L.; Lange, Norbert

2018-01-01

Protoporphyrin IX (PpIX) as natural photosensitizer derived from administration of 5-aminolevulinic acid (5-ALA) has found clinical use for photodiagnosis and photodynamic therapy of several cancers. However, broader use of 5-ALA in oncology is hampered by its charge and polarity that result in its reduced capacity for passing biological barriers and reaching the tumor tissue. Advanced drug delivery platforms are needed to improve the biodistribution of 5-ALA. Here, we report a new approach for the delivery of 5-ALA. Squalenoylation strategy was used to covalently conjugate 5-ALA to squalene, a natural precursor of cholesterol. 5-ALA-SQ nanoassemblies were formed by self-assembly in water. The nanoassemblies were monodisperse with average size of 70 nm, polydispersity index of 0.12, and ζ-potential of + 36 mV. They showed good stability over several weeks. The drug loading of 5-ALA was very high at 26%. In human prostate cancer cells PC3 and human glioblastoma cells U87MG, PpIX production was monitored in vitro upon the incubation with nanoassemblies. They were more efficient in generating PpIX-induced fluorescence in cancer cells compared to 5-ALA-Hex at 1.0 to 3.3 mM at short and long incubation times. Compared to 5-ALA, they showed superior fluorescence performance at 4 h which was diminished at 24 h. 5-ALA-SQ presents a novel nano-delivery platform with great potential for the systemic administration of 5-ALA.

Interstitial photodynamic therapy in combination with Cetuximab for recurrent head and neck squamous cell carcinoma

NASA Astrophysics Data System (ADS)

Rigual, Nestor; Dildeep, Ambujakshan; Shafirstein, Gal

2013-03-01

Background and Purpose: Combination therapy of interstitial photodynamic therapy (iPDT) with Cetuximab to attain symptomatic control of recurrent head and neck cancer. Methods: Two patients with Unresectable recurrent Head and Neck SCC were treated with iPDT alone and iPDT and cetuximab. Treatments were administered in an outpatient setting. A single dose of Photofrin at 2 mg per kilogram of body weight was administered intravenously two days prior to laser illumination. The iPDT was accomplished by delivering 630-nm laser light through two laser fibers with 2.5 and 5 cm long diffusive ends. Light irradiance of 400 mW/cm for 250 seconds was used to deliver a total of 100 J/cm, during the iPDT. Light applications were conducted, twice, at 3-4 days interval. One of the patients was treated with cetuximab along with iPDT. Results: Near total resolution of tumor was observed in the patient treated with iPDT and cetuximab, and partial resolution was seen in the patient treated with iPDT alone. Conclusion: Interstitial photodynamic therapy may be used to treat patients with recurrent unresectable head and neck cancer. The combination of iPDT with Cetuximab has the potential to improve tumor response in the patient population for whom there is no effective therapies. This observation merits further studies.

Encapsulation of curcumin in polymeric nanoparticles for antimicrobial Photodynamic Therapy

PubMed Central

Trigo Gutierrez, Jeffersson Krishan; Zanatta, Gabriela Cristina; Ortega, Ana Laura Mira; Balastegui, Maria Isabella Cuba; Sanitá, Paula Volpato; Pavarina, Ana Cláudia; Barbugli, Paula Aboud

2017-01-01

Curcumin (CUR) has been used as photosensitizer in antimicrobial Photodynamic Therapy (aPDT). However its poor water solubility, instability, and scarce bioavalibility hinder its in vivo application. The aim of this study was to synthesize curcumin in polymeric nanoparticles (NP) and to evaluate their antimicrobial photodynamic effect and cytoxicity. CUR in anionic and cationic NP was synthesized using polylactic acid and dextran sulfate by the nanoprecipitation method. For cationic NP, cetyltrimethylammonium bromide was added. CUR-NP were characterized by physicochemical properties, photodegradation, encapsulation efficiency and release of curcumin from nanoparticles. CUR-NP was compared with free CUR in 10% dimethyl sulfoxide (DMSO) as a photosensitizer for aPDT against planktonic and biofilms (mono-, dual- and triple-species) cultures of Streptococcus mutans, Candida albicans and Methicillin-Resistant Staphylococcus aureus. The cytotoxicity effect of formulations was evaluated on keratinocytes. Data were analysed by parametric (ANOVA) and non-parametric (Kruskal-Wallis) tests (α = 0.05). CUR-NP showed alteration in the physicochemical properties along time, photodegradation similar to free curcumin, encapsulation efficiency up to 67%, and 96% of release after 48h. After aPDT planktonic cultures showed reductions from 0.78 log10 to complete eradication, while biofilms showed no antimicrobial effect or reductions up to 4.44 log10. Anionic CUR-NP showed reduced photoinactivation of biofilms. Cationic CUR-NP showed microbicidal effect even in absence of light. Anionic formulations showed no cytotoxic effect compared with free CUR and cationic CUR-NP and NP. The synthesized formulations improved the water solubility of CUR, showed higher antimicrobial photodynamic effect for planktonic cultures than for biofilms, and the encapsulation of CUR in anionic NP reduced the cytotoxicity of 10% DMSO used for free CUR. PMID:29107978

Switching From Conventional Photodynamic Therapy to Daylight Photodynamic Therapy For Actinic Keratoses: Systematic Review and Meta-analysis.