No significant correlation was found between MKP-1 expression and clinical characteristics of patients, including age (<65 vs ⩾65 years old), sex, tumour primary site (colon vs rectum), tumour size (T1–2 vs T3–4), nodal status (positive vs negative), cetuximab regimen (irinotecan vs oxaliplatin), number of previously received chemotherapy metastatic lines (<2 vs ⩾2 lines), hepatic, lung, ascites and other metastases (present vs absent for each metastatic site) and metastasectomy. This evidence concerns the gene DUSP1 and neoplasm.