Objective: To investigate the clinical significance of serum let-7a-5p and miR-21-5p in the diagnosis of breast cancer.
Methods: We examined 32 healthy people and 30 patients with benign breast lesions as controls and 90 breast cancer patients as study subjects. The expression of let-7a-5p and miR-21-5p were detected in all subjects' samples, and Cel-miR-39-3p was used as a spike-in reference. Serum miRNAs were extracted by the TRIzol method, and reverse transcription was performed with specific primers for let-7a-5p, miR-21-5p and Cel-miR-39-3p, and 2-μL reverse transcription products were used as PCR templates. A SLAN-96P fluorescent quantitative PCR instrument was used for quantitative PCR detection.
Results: (1) The serum levels of carcinoembryonic antigen (CEA)and carbohydrate antigen 15-3 (CA15-3) in the breast cancer group were higher than those in the healthy controls and patients with benign breast lesions; (2) The expression level of let-7a-5p in the serum of the breast cancer group was lower than that in the healthy control group (P<0.05), but there was no significant difference compared to the breast benign lesion group (P>0.05); (3) The serum expression level of miR-21-5p in the breast cancer group was lower than that in the healthy control group (P<0.05) but was not significantly different from that in the patients with benign breast lesions (P>0.05).
Conclusion: Reduced expression of Let-7a-5p and miR-21-5p levels is of little value for early diagnosis of breast cancer; however reduced expression of Let-7a-5p and miRNA-21-5p may serve as non-invasive biomarkers for the diagnosis of breast cancer metastasis, and combination of these markers with CEA and CA15-3 can help to distinguish benign breast lesions from breast cancer.
Keywords: Cel-miR-39-3p; Fluorescence quantitative PCR; Serum miRNAs; let-7a-5p; miR-21-5p.
© 2019 by the Association of Clinical Scientists, Inc.