C1QA and central nervous system cancer: From the analysis performed on several datasets such as Sun's, French's, TCGA's, Rickman's, Bredel 2's, and Liang's, a significantly higher mRNA expression levels for C1qA, C1qB, and C1qC chains were detected in gliomas (different histotypes and grades) as compared to normal brain tissue (Figure 1, P < 0.05; Table 2).