Interleukin 37 Expression was Negatively Associated with Pathological Grading in Human Gliomas
Abstract Background: Little is known about the roles of interleukin 37 (IL-37), a newly identified cytokine, in the pathogenesis of cancer. In this study, we aimed to determine the expression of IL-37 in gliomas with different pathological grades and evaluated its effects on survival. Methods: Ninety-five participants with different pathological grades of glioma were included in this study, which were classified into grade I-II (n=27), grade III (n=30), and grade IV (n=38). Ten normal brain tissues that were resected for intracranial decompression after traumatic brain injuries served as control group. The expression of IL-37 mRNA and protein in glioma tissues was determined using Real-time PCR and immunohistochemical techniques. The association between IL-37 expression and various clinicopathologic factors was evaluated. Results: IL-37 mRNA was expressed in normal tissues and tumor tissues, and the expression of IL-37 in tumor tissues were significantly higher than normal brain tissue (p<0.05). IL-37 expression showed decline with the increase of grade level. The expression of IL-37 was significantly lower in glioma tissues of a high malignancy compared with the glioma tissues of a low malignancy. Patients with low IL-37 expression showed a shorter survival time. Conclusions: Low IL-37 expression was negatively correlated with pathological grade, rather than pathological type. Low IL-37 was positively correlated with survival time. Thus, IL-37 maybe plays an inhibitory role in glioma progression.