Figure 3.
COL5A2 gene and protein expressions are prognostic markers of CRC. (A) Kaplan-Meier analysis of the overall survival (OS) and disease free survival (DFS) of CRC patients based on COL5A2 gene expression using Smith Colorectal dataset (GSE17536) from Oncomine database.27 The low or high expression of COL5A2 was defined as lower-than the median (≤ median) or higher-than the median (> median). The case numbers of each group are indicated in the blankets. The p value was calculated using the Log-rank (Mantel-Cox) test. (B) COL5A2 protein expression was analysed in CRC using two commercial TMAs containing 180 CRC and paired normal tissues. The “full tissue spot”, the “stromal” region and the “epithelial” region were defined manually and the staining intensities were calculated automatically using the Positive Pixel Count algorithm v9.1 with Aperio ImageScope. The Positivity value was used to represent the expression level of COL5A2 protein. The optimal cutoff to dichotomize the cases was determined dynamically using X-title v3.6.1.17