Transcranial photosensitiser-free laser treatment of glioblastoma in rat brain

AbstractFor sixty years, laser technologies have undergone a technological revolution and become one of the main tools in biomedicine, particularly in neuroscience, neurodegenerative diseases and brain tumours. Glioblastoma is the most lethal form of brain cancer with very limited treatment options and a poor prognosis. In this study on rats we demonstrate that the glioblastoma (GBM) growth can be suppressed by photosensitiser-free laser-treatment (PS-free-LT) using a quantum-dot based 1267 nm laser diode. This wavelength, highly absorbed by oxygen, is capable of turning triplet oxygen to singlet form. Applying the 1267nm laser irradiation for a 4 week course with a total dose of 12.7 kJ/cm2firmly suppresses GBM growth and increases the survival rate from 34% up to 64%, presumably via the LT-activated apoptosis, inhibition of proliferation of the tumour cells, reduction of the intracranial pressure and stimulation of the lymphatic drainage and clearing functions. The PS-free-LT is promising breakthrough technology when developed and clinically approved becomes a successful non- or minimally-invasive therapy for superficial GBMs in infants as well as in adult patients with high photosensitive or an allergic reaction to PSs.