Photoprotective Effect of the PlantCollaea argentinaagainst Adverse Effects Induced by Photodynamic Therapy

Photodynamic therapy (PDT) is a treatment modality for tumours and other accessible lesions based on the combination of light and a photosensitizer (PS) accumulated in the target tissue. The main disadvantage of PDT is PS retention after treatment during long time periods that conduces to cutaneous damage. It is believed that singlet oxygen is responsible for that skin photosensitization. The aim of this work was to evaluate the photoprotective activity of the methanolic extract of the Argentinian plantCollaea argentinaagainst PDT under several treatments and employing different PSs.C. argentinaexhibited photoprotective activity against aminolevulinic acid- (ALA-) PDT in the LM2 murine adenocarcinoma cell line. The photoprotection was dependant on the extract concentration and the incubation time, being detectable from 40 μg/mL onwards and at least after 3 h exposure of the cells.C. argentinaextract protects these mammalian tumor cells against PDT effects, and it interferes with the oxygen singlet production from PSs during PDT treatment. We propose that it will be a promising agent to protect cells against PDT-induced skin sensitivity.

Download Full-text

Modulation of 5-Aminolevulinic acid mediated photodynamic therapy induced cell death in a human lung adenocarcinoma cell line

Integrative Cancer Science and Therapeutics ◽

10.15761/icst.1000187 ◽

2016 ◽

Vol 3 (3) ◽

pp. 450-459

Author(s):

Teijo MJ ◽

Diez B ◽

Batlle A ◽

Haydée Fukuda

Keyword(s):

Cell Death ◽

Photodynamic Therapy ◽

Lung Adenocarcinoma ◽

Cell Line ◽

Human Lung ◽

Aminolevulinic Acid ◽

Adenocarcinoma Cell Line ◽

Adenocarcinoma Cell ◽

Lung Adenocarcinoma Cell Line ◽

Human Lung Adenocarcinoma Cell

Download Full-text

Influence of light fluence rate on the effects of photodynamic therapy in an orthotopic rat glioma model

Journal of Neurosurgery ◽

10.3171/jns.2006.104.1.109 ◽

2006 ◽

Vol 104 (1) ◽

pp. 109-117 ◽

Cited By ~ 57

Author(s):

Even Angell-Petersen ◽

Signe Spetalen ◽

Steen J. Madsen ◽

Chung-Ho Sun ◽

Qian Peng ◽

...

Keyword(s):

Photodynamic Therapy ◽

Aminolevulinic Acid ◽

Local Treatment ◽

Local Therapy ◽

Target Tissue ◽

Fluence Rate ◽

High Fluence ◽

Tumor Induction ◽

Light Delivery ◽

Significant Prolongation

Object Failure of treatment for high-grade gliomas is usually due to local recurrence at the site of resection, indicating that a more aggressive local therapy could be beneficial. Photodynamic therapy (PDT) is a local treatment involving the administration of a tumor-localizing photosensitizing drug, in this case aminolevulinic acid (ALA). The effect depends on the total light energy delivered to the target tissue, but may also be influenced by the rate of light delivery. Methods In vitro experiments showed that the sensitivity to ALA PDT of BT4C multicellular tumor spheroids depended on the rate of light delivery (fluence rate). The BT4C tumors were established intracranially in BD-IX rats. Microfluorometry of frozen tissue sections showed that photosensitization is produced with better than 200:1 tumor/normal tissue selectivity after ALA injection. Four hours after intraperitoneal ALA injection (125 mg/kg), 26 J of 632 nm light was delivered interstitially over 15 (high fluence rate) or 90 (low fluence rate) minutes. Histological examination of animals treated 14 days after tumor induction demonstrated extensive tumor necrosis after low-fluence-rate PDT, but hardly any necrosis after high-fluence-rate treatment. Neutrophil infiltration in tumor tissue was increased by PDT, but was similar for both treatment regimens. Low-fluence-rate PDT administered 9 days after tumor induction resulted in statistically significant prolongation of survival for treated rats compared with nontreated control animals. Conclusions Treatment with ALA PDT induced pronounced necrosis in tumors only if the light was delivered at a low rate. The treatment prolonged the survival for tumor-bearing animals.

Download Full-text

Photodynamic Therapy in Refractory Mycosis Fungoides: A Prospective, Open-Label Study

Blood ◽

10.1182/blood-2020-141119 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 32-32

Author(s):

Caitlin M Brumfiel ◽

Kevin J Severson ◽

Meera H Patel ◽

Helen J L Cumsky ◽

Brenda F Ginos ◽

...

Keyword(s):

Photodynamic Therapy ◽

Mycosis Fungoides ◽

Blue Light ◽

Ad Hoc ◽

Aminolevulinic Acid ◽

Objective Response ◽

Response Rates ◽

Physician Global Assessment ◽

Target Tissue ◽

Open Label

Background:Case reports suggest photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an effective treatment for refractory mycosis fungoides (MF). No prospective trials have examined the use of ALA-PDT in MF. Objective:We aimed to assess the efficacy of ALA-PDT in refractory MF. Methods:This was a prospective study at Mayo Clinic in Scottsdale, Arizona in patients ≥ 18 years with plaque-stage treatment-refractory MF. Monthly sessions of ALA with blue light PDT were administered for up to six months. Responses were measured by Composite Assessment of Index Lesion Severity (CAILS) and Physician Global Assessment (PGA). Ad hoc analysis with modified CAILS (mCAILS) was performed, eliminating hyperpigmentation from scoring. Results:Eleven patients (30 total lesions) were treated. Six patients completed the trial per protocol. Objective response rates were 36.4% by PGA (10.9-69.2%), 18.2% by CAILS (2.3-51.8%), and 36.4% by mCAILS (10.9-69.2%). Limitations:Five patients did not complete all six PDT cycles per protocol, possibly accounting for reduced efficacy. Conclusion:ALA-PDT with blue light irradiation was moderately effective and well tolerated in refractory plaque stage MF. Lower response rates compared to similar trials may be partially explained by utilization of strict lesional assessment criteria and other variations in methodology. Disclosures Mangold: MiRagen:Research Funding;Sun Pharma:Research Funding;Elorac:Research Funding;Kirin:Membership on an entity's Board of Directors or advisory committees;Solagenix:Research Funding. OffLabel Disclosure: Photodynamic therapy is a two-step therapy in which a drug that acts as a photosensitizer is administered to target a diseased tissue, followed by illumination with visible light to activate the drug and destroy the target tissue. PDT has been used to treat internal cancers as well as treatment of cancer and precancer of the skin.

Download Full-text