scholarly journals The relationship between protoporphyrin IX photobleaching during real-time dermatological methyl-aminolevulinate photodynamic therapy (MAL-PDT) and subsequent clinical outcome

2010 ◽  
Vol 42 (7) ◽  
pp. 613-619 ◽  
Author(s):  
Jessica S. Tyrrell ◽  
Sandra M. Campbell ◽  
Alison Curnow
Cancers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 72 ◽  
Author(s):  
Jessica Tyrrell ◽  
Cheryl Paterson ◽  
Alison Curnow

Photodynamic therapy (PDT) is a light activated drug therapy that can be used to treat a number of dermatological cancers and precancers. Improvement of efficacy is required to widen its application. Clinical protoporphyrin IX (PpIX) fluorescence data were obtained using a pre-validated, non-invasive imaging system during routine methyl aminolevulinate (MAL)-PDT treatment of 172 patients with licensed dermatological indications (37.2% actinic keratosis, 27.3% superficial basal cell carcinoma and 35.5% Bowen’s disease). Linear and logistic regressions were employed to model any relationships between variables that may have affected PpIX accumulation and/or PpIX photobleaching during irradiation and thus clinical outcome at three months. Patient age was found to be associated with lower PpIX accumulation/photobleaching, however only a reduction in PpIX photobleaching appeared to consistently adversely affect treatment efficacy. Clinical clearance was reduced in lesions located on the limbs, hands and feet with lower PpIX accumulation and subsequent photobleaching adversely affecting the outcome achieved. If air cooling pain relief was employed during light irradiation, PpIX photobleaching was lower and this resulted in an approximate three-fold reduction in the likelihood of achieving clinical clearance. PpIX photobleaching during the first treatment was concluded to be an excellent predictor of clinical outcome across all lesion types.


2019 ◽  
Vol 20 (5) ◽  
pp. 1229 ◽  
Author(s):  
Marta Mascaraque ◽  
Pablo Delgado-Wicke ◽  
Alejandra Damian ◽  
Silvia Lucena ◽  
Elisa Carrasco ◽  
...  

Photodynamic therapy (PDT) constitutes a cancer treatment modality based on the administration of a photosensitizer, which accumulates in tumor cells. The subsequent irradiation of the tumoral area triggers the formation of reactive oxygen species responsible for cancer cell death. One of the compounds approved in clinical practice is methyl-aminolevulinate (MAL), a protoporphyrin IX (PpIX) precursor intermediate of heme synthesis. We have identified the mitotic catastrophe (MC) process after MAL-PDT in HeLa human carcinoma cells. The fluorescence microscopy revealed that PpIX was located mainly at plasma membrane and lysosomes of HeLa cells, although some fluorescence was also detected at endoplasmic reticulum and Golgi apparatus. Cell blockage at metaphase-anaphase transition was observed 24 h after PDT by phase contrast microscopy and flow cytometry. Mitotic apparatus components evaluation by immunofluorescence and Western blot indicated: multipolar spindles and disorganized chromosomes in the equatorial plate accompanied with dispersion of centromeres and alterations in aurora kinase proteins. The mitotic blockage induced by MAL-PDT resembled that induced by two compounds used in chemotherapy, taxol and nocodazole, both targeting microtubules. The alterations in tumoral cells provided evidence of MC induced by MAL-PDT, resolving mainly by apoptosis, directly or through the formation of multinucleate cells.


2012 ◽  
Vol 17 (11) ◽  
pp. 115007 ◽  
Author(s):  
Filippo Piffaretti ◽  
Anna Maria Novello ◽  
Rajendran Senthil Kumar ◽  
Eddy Forte ◽  
Cédric Paulou ◽  
...  

2016 ◽  
Vol 5 (2) ◽  
Author(s):  
Sergey Gamayunov ◽  
Ilya Turchin ◽  
Ilya Fiks ◽  
Kseniya Korchagina ◽  
Mikhail Kleshnin ◽  
...  

AbstractPhotodynamic therapy (PDT) has been successfully used in clinical practice for decades; however, clinical outcome data are not always consistent resulting in a great necessity for real-time monitoring to predict the therapy outcome.In a retrospective clinical study, 402 patients with non-melanoma skin malignancies were enrolled who underwent PDT treatment and fluorescence real-time imaging. The photosensitizer used was a chlorine e6 derivative (FotoditazinBaseline


Dermatology ◽  
2013 ◽  
Vol 227 (3) ◽  
pp. 214-225 ◽  
Author(s):  
Filippo Piffaretti ◽  
Matthieu Zellweger ◽  
Behrooz Kasraee ◽  
Jérôme Barge ◽  
Denis Salomon ◽  
...  

2021 ◽  
Vol 14 (4) ◽  
pp. 333
Author(s):  
Hans Christian Wulf ◽  
Ida M. Heerfordt ◽  
Peter Alshede Philipsen

Photodynamic therapy (PDT) with methyl aminolevulinate (MAL) is a popular treatment for actinic keratoses (AK), and several PDT treatment modalities with similar cure rates are in use. The effect relies on the activation of protoporphyrin IX (PpIX) in premalignant cells. This study aimed to measure PpIX during each treatment modality to determine the minimal PpIX activation and shortest exposure time for optimal cure rate. In four different treatment modalities, we established the PpIX formation up to three hours after MAL application without illumination and measured the speed of PpIX photoactivation during 9 min of red light (37 J/cm2). The level of PpIX three hours after MAL application was set to 100 PpIX units. In comparison, 85 PpIX units were formed during daylight PDT, 57 PpIX units during pulse PDT, and 52 PpIX units without any curettage prior to MAL. The activation of 50 PpIX units should, therefore, be enough to obtain a full effect on AK. Further, red light illumination may be shortened from 9 min to 1–2 min. The results indicate that PDT can be performed successfully with half the illumination time used in daylight PDT today and with one fourth of the illumination time used in classical PDT.


Sign in / Sign up

Export Citation Format

Share Document