Furthermore, comparison of NOD1 levels between primary tumour tissues from patients with CRC‐LM and tumour tissues from patients with CRC‐NLM, revealed that NOD1 upregulation was more pronounced in primary tumour tissues from patients with CRC‐LM (Figure 6g), implying that high levels of NOD1 may contribute to tumour metastasis in the liver. Here, NOD1 is linked to neoplasm.