In addition, statistical analysis showed that miR-21 and miR-155 RNAs are significantly detected in the plasma of BC patients compared to healthy specimens (P < 0.05).
The mRNA and protein levels of CADM1 showed opposite expression patterns to that of miR-155-3p expression detected, and miR-155-3p could negatively regulate CADM1 expression in breast cancer MCF-7 cells.
Patients with breast cancer with increased miRNA-21 and miRNA-155 and decreased miRNA-126 expressions had significantly worse disease-free survival, while only miRNA-21 and miRNA-126 showed poor OS (P< 0.005).
In conclusion, detection of the miRNA-17-5p, miR-155 and miRNA-222 expression levels in serum samples is significant promising molecular markers for early breast cancer diagnosis.
In summary, we have demonstrated that the transfer of miR-155 from exosomes acts as an oncogenic signal reprograming systemic energy metabolism and leading to cancer-associated cachexia in breast cancer.
In the present study, we have evaluated the expression of 6 circulating miRNAs, (miR-16, miR-21, miR-23α, miR-146α, miR-155 and miR-181α), in operable BCa patients, with non-metastatic, invasive ductal carcinoma, not receiving neoadjuvant chemotherapy.
This method has been applied also for the determination of miR-155 in the human breast carcinoma MCF-7 cells and normal human embryonic kidney cell line (HEK 293).
Soft agar colony formation assay and tumor xenografts showed inhibition of miR-155 could significantly reduce proliferation of cancer cells in vivo and vitro, which confirmed that miR-155 is an effective therapeutic target of breast cancer.
Through the conditional expression of microRNA-155 in breast cancer models, we identify and validate IKKε (IKBKE) as a downstream target and an essential effector of Pax-5-mediated suppression of NF-κB signaling.
By virtue of these advantages, the PA nanoprobes may provide a powerful platform for in situ detection of miR-155 and thus real-time monitoring of tumorigenesis and drug response in breast cancer.
The developed biosensor not only was capable to identification of fully matched versus one-base mismatch miRNA-155 sequence, but also it could detect target miRNA-155 in spiked real human serum and extracts from human breast cancer cell-line samples.
Certain well-known oncogenes (MYC and HGF), cytokines (CSF2, IFNG and IL5) and microRNAs (miR-21, miR-155-5p and let-7) may participate in the ILF2 expression network in breast cancer.
Wound fluids affect miR-21, miR-155 and miR-221 expression in breast cancer cell lines, and this effect is partially abrogated by intraoperative radiation therapy treatment.
As a result, the relatively larger (<100 nm) particles precipitated by PEG5k clearly exhibited the greatest amount of epithelial cell adhesion molecule (EpCAM), from both breast cancer (MCF-7) and colon cancer (HCT116) cells, and a larger quantity of microRNA (miRNA) specific to breast cancer cells (miRNA155 for MCF-7) seemed to be contained in the PEG-precipitated particles.