Abstract

In order to investigate the relationship between complement component 1q (A, B, C) and prognosis of colorectal cancer, we analyzed C1q (A, B, C) expression, clinical stage and methylation level in colorectal cancer from the Cancer Genome Atlas database and Gene Expression Omnibus database, including the prognosis of colorectal cancer. Complement 1q (A, B, C) were overexpressed (p=6.16e-07, p=4.01e-06 and p=3.28e-08, respectively) and showed low methylation levels (p=2.51e-11, p<1e-12 and p=1.64e-12, respectively) in colorectal cancer as per the cancer genome atlas database. The expression of C1q (A, B, C) were high in tumor tissues than normal tissues as per gene expression omnibus database (p=0.0044, p=8.9e-07 and p=5.2e-07, respectively). Additionally, C1q (A, B, C) and microsatellite instability have statistical significance (p=2.96e-08, p=1.08e-06 and p=4.18e-07, respectively). Finally, high expression of C1q (A, C) denotes poor survival in 5 y (p=0.026 and p=0.041, respectively) while high and low expression of C1q B have no significant difference survival in 5 y (p=0.082). However, the survival time is more than 3000 d and the prognosis of high expression of C1qB is poor. C1q (A, B, C) were overexpressed and showed low methylation levels in colorectal cancer. In addition, close correlation of C1q (A, B, C) with microsatellite instability has been explored and high expression of C1q (A, C) depicted poor survival in 5 y.