Serum Level and Tumor Tissue Expression of Ribonucleotide-Diphosphate Reductase Subunit M2 B: A Potential Biomarker for Colorectal Cancer
Abstract Background: This study aimed to investigate whether serum level and tissue expression of Ribonucleotide-diphosphate Reductase subunit M2 B (RRM2B) could be recognized as reliable biomarkers for colorectal cancer (CRC) progression and metastasis.Methods and Results: This descriptive-analytic cohort study was conducted on 50 newly diagnosed CRC patients (stage II, III) and 50 healthy individuals. The new cases had not received any therapeutic intervention and underwent surgery immediately after the initial diagnosis. Tumorous tissues and marginal healthy tissues as control were excised to determine the mRNA tissue expression of RRM2B by Real-Time PCR. Serum RRM2B protein was measured using an ELISA method once in the control group and in the patients before, one, and three months after surgery. The tumor metastasis node (TMN) classification system and liver metastasis were evaluated in CRC patients. The mean RRM2B gene expression in tumor tissue was 51% lower than adjacent normal tissue (P < 0.001). We did not find a significant relationship between serum level of RRM2B and tumor staging and metastasis in patients before surgery (P = 0.373, P = 0.189), one month after surgery (P = 0.960, P = 0.088), and three months after surgery (P = 0.407, P = 0.724). RRM2B expression in tumor tissue was not associated with tumor staging and metastasis (P = 0.254, P = 0.721)Conclusion: Our study indicates the first time evidence that RRM2B may serve as a potential biomarker for CRC.