Abstract 45P
Background
Breast cancer (BC) is one of the most common cancer types reported worldwide. Benign breast tumours such as fibroadenomas (FBA) share certain features with cancerous cells and constitute major proportion of reported cases of breast-associated malignancies yet the in-depth molecular mechanisms contributing to benign tumours remains least explored. Dysregulation of microRNAs (miRNAs) is shown to play an important role in pathogenesis of BC however, the information on expression patterns and involvement of miRNAs in benign tumours of breast remains largely unknown. The present study aimed at performing comparative expression profiling of a panel of miRNAs (miR-21, -155, -221) that are known to exhibit oncogenic, tumour-suppressor, proliferation and immunogenic properties in a well-established breast tissue cohort of type; benign, malignant and non-cancerous (paired adjacent).
Methods
The study cohort comprised of 121 participants (pre-operative/treatment-naive BC (n) = 69; FBA (n) = 52). The expression levels of selected miRNAs were measured via qPCR. Receiver operating characteristic curve analysis was performed to determine the diagnostic potential of miRNAs.
Results
The expression level of all three miRNAs, miR-21, -155 and -221 was significantly upregulated in BC vs. adjacent non-tumour tissues (P < 0.05). In FBA vs. adjacent non-tumour tissues, only miR-21 was significantly upregulated (P=0.027). Both miR-155 and miR-221 were significantly upregulated in BC vs. FBA (P< 0.01 and < 0.005) exhibiting tumour-specific expression pattern. Furthermore, miR-155, and miR-221 but not miR-21 were able to differentiate BC patients from FBA with an AUC of 0.979 (sensitivity (SN): 94.74%; specificity (SP): 100%) and 0.707 (SN: 94.74%; SP: 100%) respectively.
Conclusions
miR-21, -155, and -221 panel have the potential to serve as malignancy specific-markers in breast tumours. It is expected that the findings of present study will help in understanding role of miRNAs information and progression of benign and malignant breast tumours. Further studies are underway to determine non-invasive biomarker potential of these miRNAs in discriminating early-stage BC and FBA patients.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Nida Matloob.
Funding
COMSATS University Islamabad (CUI).
Disclosure
All authors have declared no conflicts of interest.