GUCA2A and neoplasm: • GUCA2A was identified as a hubgene in CRC.• GUCA2A expression was significantly correlated with the OS of CRC patients.• qPCR analysis showed that GUCA2A expression in tumor and metastatic tissues was significantly low compared with adjacent normal tissues.• GUCA2A has a potential diagnostic value for CRC patients with 80.6% sensitivity and 83.5% AUC.