Establishment And Verification Of In Site Reproducible Xenograft Model Of Spinal Glioma

Intramedullary spinal cord glioma is a disease that occupied 2%to 4%of all primary central nervous system tumor,with low morbidity and high mortality and disability.However,even though the prognosis of spinal glioma is poor,with current treatment guidelines aiming at intracranial tumor so far,there are no unified treatment guideline to spinal gliomas,which causes the situation of diverse treatment strategy and effect in different units.Furthermore,limited capacity of the spinal canal is one of the reasons why prognosis of spinal glioma is poor.It is difficult for spinal canal space to compensate for tumor growth,resulting in severe compressive symptom and rapid aggravation.However,recently,literatures have confirmed that the tumor genetic inducers involved in spinal glioma were not same as those in intracranial glioma,therefore,molecular mechanisms were different between them.It is indispensable to study the molecular mechanism of spinal glioma and search for molecular targets of therapy.However,there is still lack of effective animal models of spinal tumors,which limits the researching progress in this field to some extent.Aiming to establish an experimental animal model for further research and verify its stability and replicability.Firstly,three strains of mice were dissected and their spinal cords were taken out for measurement to determine the best puncture point.And to determine the appropriate dose of xenograft,24 mice of C57BL were selected and randomly divided into 4 groups with 6 cases in each group.The experimental group was injected with 1μL,2μL or 3 μL GL261 cell lines.The mice were observed at regular intervals and their function were evaluated according to the BBB scale.When the BBB score was 5 points or less,their spinal cord tissues with tumors were taken out for histological examination.After that,18 mice were randomly divided into 3 groups with 6 mice in each group,and 2 strains of human source primary spinal glioma cells were used to verify the replicability of the model.Through anatomical experiment,we found that the cervical lamina of mice was thinner than that of thoracic or lumbar lamina,and the intervertebral space was much wider and the adhesion muscles are more easily separated.The volume of spinal cord is relatively larger at the plane of the line between the midpoints of scapulae.According to the result of spinal cord sections,the best puncture point we identified was located on 0.9mm sideward of posterior median line at the level of the line between midpoints of scapulae,with the depth of 0.9mm.In the xenograft experiment of C57BL,we found that the transient motor function injury observed was mild in the 2μL group and its tumorigenesis time approached to that in the 3μL group.Histological examination showed that tumor cells were successfully implanted in the white matter of spinal cord.In the xenograft experiment of nude mice,the implanted tumor tissue retained the pathological characteristics of their original tumor.This study established a tumorigenesis method for the spinal glioma,providing a stable and reliable animal model for further study on its molecular research and targeted therapy.