Aberrant expression of a five‐microRNA signature in breast carcinoma as a promising biomarker for diagnosis

Abstract

Background Breast cancer (BC) is the most common malignancy among females with dismal quality of life in patients. It has been proven that epigenetic factors, especially microRNAs, are involved in breast carcinogenesis and progression. This study aimed to assess the expression and clinical performances of a five‐microRNA signature (miR‐127‐3p, miR‐133a‐3p, miR‐155‐5p, miR‐199b‐5p, and miR‐342‐5p) in breast cancer and adjacent normal tissues to identify a potential biomarker for BC and investigate the relationship between their expression and clinicopathological features of BC patients as well. Methods In this case‐control investigation, we recruited 50 pairs of tumor and matched non‐tumor surgical specimens from patients diagnosed with BC. Expression levels of miR‐127‐3p, miR‐133a‐3p, miR‐155‐5p, miR‐199b‐5p, and miR‐342‐5p were measured in BC and adjacent normal tissues by RT‐qPCR. Results We found that miR‐127‐3p, miR‐133a‐3p, miR‐199b‐5p, and miR‐342‐5p were significantly down‐regulated, while miR‐155‐5p was significantly up‐regulated in BC tumor tissues compared with the corresponding adjacent normal tissues. The decreased expression of miR‐127‐3p, miR‐133a‐3p, miR‐342‐5p, and up‐regulation of miR‐155‐5p showed a significant correlation with disease stage. We also found a significant down‐regulation of miR‐127‐3p, miR‐199b‐5p, and miR‐342‐5p compared in HER‐2‐negative patients. Our results indicated that miR‐155‐5p had a higher expression level in HER‐2‐positive patients. Receiver operating characteristic (ROC) curve analysis demonstrated that all these five microRNAs can serve as potential biomarkers to distinguish between tumor and non‐tumor breast tissue samples. Conclusions The present findings suggested that dysregulation of this five‐miRNA signature might be considered as a promising and functional biomarker for BC diagnosis.

MiR‐133a‐3p attenuates resistance of non‐small cell lung cancer cells to gefitinib by targeting SPAG5

“…In this study, we successfully established a gefitinib‐resistant cell line (PC9/GR) and found that miR‐133a‐3p was significantly downregulated in the gefitinib‐resistant cell line PC9/GR compared with gefitinib‐sensitive cell line PC9. Previously, miR‐133a‐3p has been reported to be downregulated in many cancers, and low expression of miR‐133a‐3p was associated with tumor recurrence, metastasis, drug resistance, and poor prognosis of cancer patients 32‐34 . Our results also indicate that low expression of miR‐133a‐3p in lung cancer tissues is associated with poor prognosis in patients with lung cancer.…”

“…Previously, miR‐133a‐3p has been reported to be downregulated in many cancers, and low expression of miR‐133a‐3p was associated with tumor recurrence, metastasis, drug resistance, and poor prognosis of cancer patients. 32 , 33 , 34 Our results also indicate that low expression of miR‐133a‐3p in lung cancer tissues is associated with poor prognosis in patients with lung cancer. Thus, we hypothesized that the downregulation of miR‐133a‐3p expression may support the gefitinib resistance in PC9/GR cells.…”

Emerging roles of MiR-133a in human cancers

“…Plenty of efforts have been devoted to evaluating the efficacy of miR-133a as a diagnostic marker. By conducting a case-control investigation in 50 pairs of breast cancer and normal tissues, Bitaraf, A. et al considered miR-133a-3p, along with miR-127-3p, miR-155-5p, miR-199b-5p, and miR-342-5p, were promising biomarkers for BC 76 . MiR-133a-3p was significantly modulated in triple-negative breast cancer (TNBC), suggesting that miR-133a-3p might be a predictor of cancer invasion and prognosis 77 .…”

Validation of the four-miRNA biomarker panel MiCaP for prediction of long-term prostate cancer outcome

“…miR-133a-3p has previously been reported as downregulated in prostate cancer 29 and in other cancer types, including breast 30 , gastric 31 , oesophageal 32 , and colon cancer 33 , suggesting a tumour suppressor function of this miRNA across these cancer types.…”