[Pathomorphosis of transplanted C6 glioma treated with a 1267 nm wavelength laser]

To establish the mechanisms of pathomorphism of grafted C6 glioma (glioblastoma, GB) under the influence of 1267 nm laser therapy using in vivo experiments.

The experiment was performed on 40 Wistar rats with transplanted GB. In the experimental groups, 1 week after tumor transplantation, rats underwent daily laser therapy for 3 weeks. One therapy session lasted 51 minutes (3 laser irradiations for 17 minutes with 5-minute breaks between irradiations), at a dose of 12.6 kJ/cm² laser with a wavelength of 1267 nm. The comparison groups consisted of animals without a tumor and with a tumor, but without LT. Immunohistochemical markers of apoptosis (p53, Bax, Fas receptor), proliferation (Ki67), and autophagolysosome formation (LC3B, clathrin, and caveolin) were used. In statistical analysis, the Shapiro-Wilk test for the normality of the distribution was performed. The averages were compared using the Welch t-test.

The survival rate in the group with transplanted GB after laser therapy compared with the experimental group of animals without LT was 1.8 times higher after a course of LT with a dose of 12.6 kJ/cm² (64% and 34%, respectively). It was found that LT reduces the proliferation of GB cells (Ki67), activates the mitochondrial pathway of apoptosis (Bax and p53) in GB cells, and blocks the formation of autophagolysosomes (LC3B, clathrin, caveolin). Conclusion. Under the action of a laser (1267 nm), pronounced pathomorphosis of transplanted C6 glioma develops, its growth rate decreases, and animal survival increases from 34% to 64%. Thus, GB therapy with a laser with a wavelength of 1267 nm may become a promising therapeutic approach in the development of additional non-invasive GB treatment method.