Study of some microRNA on chromosome 19 (C19MC) in serum and breast cancer tissue

Abstract Background Breast cancer (BC) is the most prevalent cancer among females worldwide. Many studies suggest that certain RNAs play a role in carcinogenesis. The primate-specific microRNA gene cluster on chromosome 19 q27.3 region (C19MC) could regulate tumor cell proliferation, migration, and invasion. Objective In this study, we compared the expression of miRNAs of the C19MC cluster in breast cancer tumor and non-tumor samples, as well as in the serum of BC-affected and healthy individuals. Methods Peripheral blood was collected from 100 people with BC and 100 healthy individuals, and breast cancer samples of tumor and margin tissue were collected. After RNA extraction, cDNA was synthesized using RT-PCR. The expression of C19MC, including miR-515-1, miR-515-2, miR-516-A1, miR-516-A2, miR-516-B1, miR-516-B2, miR-517-A, miR-517-B, miR-517-C, and miR-518-A1, in the control-patient serum and tissue of BC and tumor margin were investigated using real-time PCR. Statistical analyses and ROC curves were generated using GraphPad Prism software (v8.04), and a p-value of 0.05 was considered significant. Results Our findings show that high expression of all C19MC miRNAs mentioned, except miR-517-B and miR-517-C, tightly correlates with BC and can be utilized as noticeable non-invasive tumor markers. Conclusion Our data support a general effect of C19MC miRNAs on BC detection and highlight the potential role of several C19MC members in this process.