The assessment of tumor vascularization degree for predicting the effectiveness of plasmon photothermal and photodynamic therapy
Alla Bucharskaya, Saratov State Medical University , Russia
Gаlina Maslyakova, Saratov State Medical University , Russia
Marina Chekhonatskaya, Saratov State Medical University, Russia
Pakhomy Svetlana, Saratov State Medical University, Russia
Mudrak Dmitry, Saratov State Medical University, Russia
Nikita Navolokin, Saratov State Medical University , Russia
Georgy Terentyuk, Research National Saratov State University, Saratov State Medical University, Russia
Ekaterina Borisova, Institute of Electronics, Bulgarian Academy of Sciences, Bulgaria
Boris Khlebtsov, Institute of Biochemistry and Physiology of Plants and Microorganisms, RAS, Russia
Nikolai Khlebtsov, Institute of Biochemistry and Physiology of Plants and Microorganisms, RAS, Russia
Vadim Genin, Research National Saratov State University, Russia
Alexey Bashkatov, Research National Saratov State University , Russia
Elina Genina, Research National Saratov State University, Russia
Valery Tuchin, Research National Saratov State University, Russia
Abstract
The aim of research was to assess the vascularization degree of tumor to predict the efficiency of plasmonic photothermal therapy (PPT) and photodynamic therapy (PDT) in tumor-bearing rats. Before any treatment, 3D Doppler ultrasound imaging was used for assessment of the vascularization degree of transplanted rat cholangiocarcinoma. For PPT, the gold nanorods with aspect ratio of 4:1, functionalized with thiolated polyethylene glycol, were used. After multiple fractional intravenous (IV) injections in rats with cholangiocarcinoma, the tumours were irradiated through the skin by an 808-nm NIR diode laser at a power density of 2.3 W/cm2 for 15 min. For PDT, galactose – Lu-phthalocyanine, as a photosensitizer, was applied by intratumoural injection, in a dose of 2 mg/kg. Then, tumors were irradiated through the skin by 670 nm-diode laser source with power density 200 mW/cm2 applied for 1000 sec in three non-overlapping zones covering whole tumour surface to obtain a total irradiation dose of 200 J/cm2 for each lesion. The withdrawal of the animals from the experiment and sampling of tissues for morphological study were performed before and 72 hrs after PPT and PDT. The vascular microdensity in tumors was assessed on histological sections as vessel counts or vessel area per unit of assessed tumor area. It was shown that efficiency of PPT and PDT therapy was mostly due by sufficient tumor accumulation of photothermosensitizers, therefore preliminary assessment of tumor vascularization degree is necessary before starting a therapy.
Speaker
Alla Bucharskaya
Saratov State Medical University
Russia
Discussion
Ask question
