<b>Localization and Efficacy Analysis of the Phototherapeutic Lutetium Texaphyrin (PCI‐0123) in the Murine EMT6 Sarcoma Model</b>

Woodburn, Kathryn W.; Fan, Quli; Miles, Dale; Kessel, David; Luo, Yukun; Young, Stuart W.

doi:10.1111/j.1751-1097.1997.tb08579.x

Cited by 107 publications

(70 citation statements)

References 13 publications

(21 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…MLu (Pharmacyclics, Inc., Sunnyvale, CA) injection was administered intravenously (0.5-2 mg/kg) 3-24 h before light administration (16,24). After the patient was anesthetized, the interstitial CDF were placed in the gland using a template with evenly spaced holes, which was attached to the TRUS unit.…”

Section: Pdt and In Vivo Light Measurementsmentioning

confidence: 99%

Optical Properties of Human Prostate at 732 nm Measured In Vivo during Motexafin Lutetium-Mediated Photodynamic Therapy

Zhu¹,

Dimofte²,

Finlay³

et al. 2004

Photochem Photobiol

View full text Add to dashboard Cite

Characterization of the tissue light penetration in prostate photodynamic therapy (PDT) is important to plan the arrangement and weighting of light sources so that sufficient light fluence is delivered to the treatment volume. The optical properties (absorption [μ a ], transport scattering [ ] and effective attenuation [μ eff ] coefficients) of 13 patients with locally recurrent prostate cancer were measured in situ using interstitial isotropic detectors. Measurements were made at 732 nm before and after motexafin lutetium (MLu)-mediated PDT in four quadrants. Optical properties were derived by applying the diffusion theory to the fluence rates measured at several distances (0.5-5 cm) from a point source. μ a and varied between 0.07 and 1.62 cm −1 (mean 0.37 ± 0.24 cm −1 ) and 1.1 and 44 cm −1 (mean 14 ± 11 cm −1 ), respectively. μ a was proportional to the concentration of MLu measured by an ex vivo fluorescence assay. We have observed, on average, a reduction of the MLu concentration after PDT, presumably due to the PDT consumption of MLu. μ eff varied between 0.91 and 6.7 cm −1 (mean 2.9 ± 0.7 cm −1 ), corresponding to an optical penetration depth (δ = 1/μ eff ) of 0.1-1.1 cm (mean 0.4 ± 0.1 cm). The mean penetration depth at 732 nm in human prostate is at least two times smaller than that found in normal canine prostates, which can be explained by a four times increase of the mean value of in human prostates. The mean light fluence rate per unit source strength at 0.5 cm from a point source was 1.5 ± 1.1 cm −2 , excluding situations when bleeding occurs. The total number of measurements was N = 121 for all mean quantities listed above. This study showed significant inter-and intraprostatic differences in the optical properties, suggesting that a real-time dosimetry measurement and feedback system for monitoring light fluences during treatment should be considered for future PDT studies. ¶ Posted on the website on 9 November 2004.

show abstract

Section: Pdt and In Vivo Light Measurementsmentioning

confidence: 99%

Optical Properties of Human Prostate at 732 nm Measured In Vivo during Motexafin Lutetium-Mediated Photodynamic Therapy

Zhu¹,

Dimofte²,

Finlay³

et al. 2004

Photochem Photobiol

View full text Add to dashboard Cite

show abstract

“…The present study is limited to four compounds: sulfonated chloro-aluminum phthalocyanine (AlPcS n ) [14], benzoporphyrin derivative monoacid ring A (BPD-MA) [15,16], lutetium texaphyrin (Lutex) [17][18][19], and aminolevulinic acid (ALA), a precursor of the endogenous sensitizer protoporphyrin IX (PpIX) [20]. In Table 1 Thursday we present some published results of the PDT efficiency, relative to Photofrin, of these selected sensitizers [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38].…”

Section: Introductionmentioning

confidence: 99%

Photodynamic parameters in the chick chorioallantoic membrane (CAM) bioassay for topically applied photosensitizers

Hammer‐Wilson

Akian

Espinoza

et al. 1999

Journal of Photochemistry and Photobiology B: Biology

View full text Add to dashboard Cite

“…32 The PS lutetium texaphyrin also accumulates preferentially in lysosomes in EMT6 murine mammary sarcoma cells. 33 Intracellular tracking of Photofrin and N-monoaspartyl chlorin e6 has revealed that the former enters the cell by diffusion and localizes in mitochondria, while the latter is endocytosed and then localized in lysosomes. 20 Incubation of bladder carcinoma cells with chlorin e6 leads to localization of the latter in the plasma membrane and other peripheral cell membranes, 34 whereas lysyl chlorin p6 is largely found in endosomes.…”

Section: Subcellular Distribution Of Photosensitizers In Vitromentioning

confidence: 99%

Targeted intracellular delivery of photosensitizers to enhance photodynamic efficiency

Jans²,

2000

View full text Add to dashboard Cite

IntroductionPhotodynamic therapy (PDT) is a relatively new cytotoxic treatment, predominantly used in anticancer approaches, that depends on the retention of photosensitizers (PS) in tumour cells and their activation within the tumour through irradiation with light of the appropriate wavelength. Photoactivated PS generate reactive oxygen species (singlet oxygen, 1 O 2 , and free radicals, such as ·OH, HO· 2 and ·O 2 -) which are able to damage cellular structures, meaning that PDT is particularly attractive as an alternative means to kill drug-and radioresistant tumour cells.1,2 Normal cells, however, are also able to accumulate PS and be damaged by them, so that prolonged skin photosensitization, light-sensitivity of the eye and other side-effects have proved to be severe limitations of PDT. When photoactivated, PS inflict damage on many types of biomolecules without any specificity, their action being mediated largely via the reactive oxygen species mentioned, none of which travel more than several tens of nanometers before reacting with a biomolecule. Keeping in mind that cell dimensions are of the order of micrometres or tens of micrometres, it is clear that the intracellular action of PS is restricted to the site of their subcellular location and the surrounding radius of not more than 40 nm.3-5 That uneven intracellular distribution of PS can lead to differences in toxicity has been shown using laser microbeam irradiation. 6In contrast to cell membranes and other cytoplasmic organelles, the cell nucleus 7-9 is known to be a very sensitive target for reactive oxygen species. In order to reduce the dose of PS administered to patients and hence minimize the harmful side-effects of PDT, new approaches have been devised to increase the effectiveness of tumour-cell killing through targeted delivery of PS to hypersensitive subcellular sites. These approaches are the focus of the present review. Subcellular distribution of photosensitizersInsomuch as most mammalian cells span tens of micrometres, it is clear that PS efficiency will depend not only on the relative distribution of PS between the tumour and surrounding tissues and between malignant and normal cells, but also on the intracellular distribution of the PS. Furthermore, membranes divide the interior of the eucaryotic cell into compartments that differ markedly in their sensitivity to reactions induced by PS-generated reactive oxygen species, in the ability of damaged molecules to be replaced/recycled and in the extent to which such damage affects cell viability and/or the capability of the cell to divide. It is noteworthy that preferential PS accumulation in tumours is itself not a guarantee of selective photoinduced tumour damage and successful PDT. In experiments on rats with gliosarcoma 9L, 10 for example, it has been found that despite a 13-fold higher accumulation of the PS Photofrin in the tumour compared with Summary Photodynamic therapy (PDT) is a novel treatment, used mainly for anticancer therapy, that depends on the retention of photosensitizer...

show abstract

Localization and Efficacy Analysis of the Phototherapeutic Lutetium Texaphyrin (PCI‐0123) in the Murine EMT6 Sarcoma Model

Cited by 107 publications

References 13 publications

Optical Properties of Human Prostate at 732 nm Measured In Vivo during Motexafin Lutetium-Mediated Photodynamic Therapy

Optical Properties of Human Prostate at 732 nm Measured In Vivo during Motexafin Lutetium-Mediated Photodynamic Therapy

Photodynamic parameters in the chick chorioallantoic membrane (CAM) bioassay for topically applied photosensitizers

Targeted intracellular delivery of photosensitizers to enhance photodynamic efficiency

Contact Info

Product

Resources

About