The Predictive Value of hsa_circ_0001313 (circCCDC66) in Egyptian Rectal Cancer Patients: A New Era in Precision Medicine

Abstract Introduction The involvement of circular RNAs (circRNAs) in cancer research has been emphasized in recent years due to evidence of their involvement in malignancy pathogenesis. Yet, the involvement of circRNAs in the resistance to cancer treatment remains to be clarified. Circular RNA 0001313 (circ_0001313) has a distinct expression in different cancers, and it is overexpressed in rectal cancer; hence, it could be a promising non-invasive stable biomarker and a therapeutic target for rectal cancer. Yet, its predictive role has not been studied in Egyptian rectal cancer patients. Objective To study the predictive value of circulating circ_0001313 (circ_CCDCC6) in assessing the response to neoadjuvant chemoradiotherapy (nCRT) in patients with rectal cancer and its relation to radiological and pathological response. Materials and Methods The present study included 50 patients with locally advanced rectal cancer and 20 healthy subjects as controls. The analysis of the relative circ_CCDCC6 expression was performed using the real-time quantitative polymerase chain reaction (qPCR) method. Results The circ_CCDCC6 was found to be significantly more expressed in rectal cancer patients compared with controls (p < 0.001). Moreover, its expression level was significantly higher in nonresponders to nCRT compared with responders (p < 0.001). Furthermore, a receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive performance of circulating circ_0001313; its sensitivity in predicting the response to treatment was of 93.33%, and its specificity was of 91.43%. Conclusion Significant up-regulation of circ_0001313 in rectal cancer suggests a potential oncogenic role, and higher expression of circ_0001313 among nonresponders suggests that it could be a predictor of the response to nCRT.