N-(2-hydroxypropyl)methacrylamide polymer conjugated pyropheophorbide-a, a promising tumor-targeted theranostic probe for photodynamic therapy and imaging.
Eur J Pharm Biopharm
; 130: 165-176, 2018 Sep.
Article
de En
| MEDLINE
| ID: mdl-29885851
ABSTRACT
Tumor-targeted photodynamic therapy (PDT) using polymeric photosensitizers is a promising therapeutic strategy for cancer treatment. In this study, we synthesized a pHPMA conjugated pyropheophorbide-a (P-PyF) as a cancer theranostic agent for PDT and photodynamic diagnostics (PDD). Pyropheophorbide-a has one carboxyl group which was conjugated to pHPMA via amide bond yielding the intended product with high purity. In aqueous solutions, P-PyF showed a mean particle size of â¼200â¯nm as it forms micelle which exhibited fluorescence quenching and thus very little singlet oxygen (1O2) production. In contrast, upon disruption of micelle strong fluorescence and 1O2 production were observed. In vitro study clearly showed the PDT effect of P-PyF. More potent 1O2 production and PDT effect were observed during irradiation at â¼420â¯nm, the maximal absorbance of pyropheophorbide-a, than irradiation at longer wavelength (i.e., â¼680â¯nm), suggesting selection of proper absorption light is essential for successful PDT. In vivo study showed high tumor accumulation of P-PyF compared with most of normal tissues due to the enhanced permeability and retention (EPR) effect, which resulting in superior antitumor effect under irradiation using normal xenon light source of endoscope, and clear tumor imaging profiles even in the metastatic lung cancer at 28â¯days after administration of P-PyF. On the contrary irradiation using long wavelength (i.e., â¼680â¯nm), the lowest Q-Band, exhibited remarkable tumor imaging effect with little autofluorescence of background. These findings strongly suggested P-PyF may be a potential candidate-drug for PDT/PDD, particularly using two different wavelength for treatment and detection/imaging, respectively.
Mots clés
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Photothérapie dynamique
/
Poly(acides méthacryliques)
/
Chlorophylle
/
Tumeurs du poumon
Type d'étude:
Diagnostic_studies
Limites:
Animals
Langue:
En
Journal:
Eur J Pharm Biopharm
Sujet du journal:
FARMACIA
/
FARMACOLOGIA
Année:
2018
Type de document:
Article