Finally, circulating exosomal miR-221-3p levels also have biological function in promoting HLECs sprouting in vitro and are closely associated with tumor miR-221-3p expression, lymphatic VASH1 expression, lymphangiogenesis, and LN metastasis in CSCC patients.
Analysis of microRNA expression dataset for human primary and metastatic PCa samples and control normal adjacent benign prostate revealed miR-221-5p to be significantly downregulated in PCa compared to normal prostate tissue and in metastasis compared to primary PCa.
MiR-221 may be involved in PTC cell invasion and metastasis by targeting RECK, indicating that the miR-221/RECK pathway could be studied further as a potential new diagnostic or prognostic biomarker for PTC.
Compared with BCa patients with low expression of miRNA-221-5p, those with high expression had a higher incidence of lymph node metastasis and distant metastasis.
An analysis of the prognostic value of the 29 miRNAs identified miR-221/miR-222 to be significantly associated with time to metastasis in both cohorts.
MicroRNAs (miRNAs/miRs) serve important roles in tumor development, progression and metastasis. miR-221 has been reported to modulate proliferation, apoptosis, cell cycle distribution and cell migration in a variety of cancers.
The receiver-operating characteristic (ROC) curves and the area under the ROC curve (AUC) suggested that the diagnostic efficacy for distant metastasis of miR-221-3p is better than CA19-9 (AUC: 0.689 vs. 0.587).
In addition, significant associations between up-regulated miR-221 and down-regulated Apaf-1 expressions and clinical stage and lymph node (LN) metastasis (P< 0.001 for each) were found.
In this article, high expression of miRNA-221 (miR-221) in exosomes of the peripheral blood was determined to be positively correlated with the poor clinical prognosis of GC, especially with respect to tumor, node, and metastases stage.
Additionally, the serum level of miR-221 in osteosarcoma patients with positive distance metastasis (P=0.01) and advanced clinical stage (P=0.006) was significantly higher than those without distance metastasis and with early clinical stage.
The RCC patients with metastasis at diagnosis also presented higher circulating expression levels of miR-221 than patients with no metastasis (2(-ΔΔCt) = 10.9, P = 0.001).
We provide insight into the behavior of miR-221 in colorectal cancer (CRC) metastasis by showing that miR-221 is significantly upregulated in metastatic CRC cell lines and tissues. miR-221 overexpression enhances, whereas miR-221 depletion reduces CRC cell migration and invasion in vitro and metastasis in vivo.
These findings indicate that miR-221 may promote trastuzumab resistance and metastasis of HER2-positive breast cancers by targeting PTEN, suggesting its role as a potential biomarker for progression and poor prognosis, and as a novel target for trastuzumab-combined treatment of breast cancers.
SW620 cells transfected with miR-221* or miR-224 mimics had reduced migration and motility in vitro and formed smaller tumors with fewer metastases in mice compared with control SW620 cells.
Furthermore, PCa patients with high plasma miR-221 concentrations had significant correlation with distant metastasis (P=0.041), and non-resectable status (P=0.021).
Both of p21(WAF1/Cip1)and TGF-β1's expression correlated with tumor differentiations. miR-221's upregulation and p27(Kip1)'s downregulation were significantly associated with tumor stages and metastasis.