Circulating MiR-126 as a potential biomarker in Egyptian colorectal cancer patients: A case-control study

Abstract

Background: Globally, colorectal cancer (CRC) is among the most prevalent malignant tumors. It is characterized by unlimited proliferation, invasion, and metastasis. MicroRNA-126 (miR-126) has been shown in many studies to play a significant role in CRC, but data regarding its role in CRC Egyptian patients are limited.

Objectives: This case-control study aimed to investigate the miR-126 as a potential marker in CRC Egyptian patients and to correlate its expression levels with CRC tumor, node, metastasis (TNM) stage, distant metastasis, and tumor size.

Methods: The study included 50 adult Egyptian participants (30 patients with CRC, 10 patients with colorectal adenoma as a pathological control, and 10 healthy controls). MiR-126 expression levels were detected using Real-Time Quantitative PCR (qPCR) along with the endogenous reference gene hsa-miR-103a in all participants.

Results: MiR-126 expression was significantly decreased in CRC patients than both control groups. It was associated with advanced TNM stage (p = 0.001) and distant metastasis (p = 0.002). However, it was not correlated with tumor size (p = 0.980), carcinoembryonic antigen (CEA) (p = 0.397), and cancer antigen 19-9 (CA19-9) (p = 0.236). The best cut-off point of miR-126 to discriminate CRC from both controls was 0.7 and to discriminate metastatic CRC from non-metastatic CRC was 0.3.

Conclusions: Our results suggest that miR-126 could be used as an early marker for CRC detection among Egyptian patients and a good prognostic indicator associated with metastasis.

Keywords: Colorectal cancer; Egyptian; MiR-126; metastasis; prognosis; tumor size.

Figure 1.

Comparison of (a) CEA levels (ng/mL), (b) CA19-9 levels (U/mL) and (c) miR-126 expression levels between the three studied groups. (a) p-value = 0.002. (b) p-value = 0.001. (c) p-value = 0.001.

Figure 2.

Comparison of (a) CEA levels (ng/mL), (b) CA19-9 levels (U/mL) and (c) miR-126 expression levels among the CRC patients according to the TNM stage; early stages (I + II), late stages (III + IV). (a) p-value = 0.001. (b) p-value < 0.001. (c) p-value = 0.001.

Figure 3.

Comparison of (a) CEA levels (ng/mL), (b) CA19-9 levels (U/mL) and (c) miR-126 expression levels among the CRC patients according to the presence of distant metastasis. (a) p-value = 0.002. (b) p-value = 0.035. (c) p-value = 0.002.

Figure 4.

ROC curve for miR-126 for discriminating between (a) CRC patients and all controls (pathological + healthy), (b) CRC patients and pathological controls, (c) CRC patients and healthy controls, and (d) CRC patients with metastasis and CRC patients without metastasis.