COL4A1 and hepatocellular carcinoma: According to log2(fold change) > 2 and p < 0.05, ROBO1 [log2(fold change) = 2.21; p < 0.001] and COL4A1 [log2(fold change) = 2.07; p < 0.001] expression levels were elevated in HCC tissues and filtered out for further investigations (Fig. 1C).