C1QC and neoplasm: C1q, the first recognition subcomponent of the complement classical pathway, includes three chains (C1qA, C1qB, and C1qC) and has been proved to highly expressed in multiple tumors, including prostate (44), and mesothelioma (45) as well as gliomas (46).In our study, the expression of C1QA were significantly correlated with ESCC patients’ survival and upregulated in tumor samples.