Expression of MiR-335 and its target metalloproteinase genes: clinical significance in breast cancer

Background: Early diagnosis of breast cancer decreases mortality rate; therefore, novel diagnostic methods are urgently required. In this study, authors aimed to investigate the role of serum-derived miR-335 in breast cancer, and the expression of matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9) and evaluating their feasibility and clinical utility as biomarkers for the early detection of breast cancer. Materials and methods: Blood samples were collected from a total of 210 individuals who were enrolled in this study. The participants were divided into newly diagnosed breast cancer patients (n = 115), patients with benign breast lesions (n =55) and healthy individuals as control group (n =40). The expression profile of miR-335, MMP2 and MMP9 were determined using quantitative polymerase chain reaction (qPCR). Results: MiR 335 expression level was down-regulated in primary breast cancer group as compared to benign breast group and healthy individuals with 98% and 94.9% sensitivity and specificity, respectively. MMP2 and MMP9 showed significantly higher expression levels in breast cancer group as compared to both benign and healthy group and reporting 92.7% and 93% sensitivity, respectively. The relations between investigated markers and pathologic types, staging, grading, and lymph node involvement were significant with these factors. Expression level of miR-335 was decreased with increased MMP2 and MMP9 at significant level. Conclusion: MiR-335, MMP2, and MMP9 can be used as diagnostic markers in breast cancer.

Automated summary

This study investigated the role of miR-335 in breast cancer and evaluated the feasibility and clinical utility of MMP2 and MMP9 as biomarkers for early detection of breast cancer. The results showed down-regulated expression of miR-335 and up-regulated expression of MMP2 and MMP9 in breast cancer, suggesting their potential as diagnostic markers for the early detection of breast cancer.