We observed that the expression level of miR-145 was positively correlated with the tumor differentiation (P = 0.015), lymph node status (P = 0.007), distant metastasis (P = 0.008), and TNM stage (P = 0.033).
Furthermore, miR-143 and miR-145 suppressed tumor sphere formation and expression of CSC markers and 'stemness' factors including CD133, CD44, Oct4, c-Myc and Klf4 in PC-3 cells.
In situ hybridization was used to evaluate miR-143 and miR-145 expression in tumor epithelial cells and stromal cells in the primary tumors and lymph nodes.
This is mediated through a downregulation of type 2 cytokines in myeloid cells and an increase in IFNγ-producing cytotoxic CD8 T lymphocytes. miR-130a- and miR-145-targeted molecular networks including TGFβ and IGF1R pathways were correlated with higher tumor stages in cancer patients.
In line with the tumor suppressive functions in vitro, the expression of miR-143 and miR-145 was lower in malignant compared to benign breast tissue, and lower in the more aggressive tumors with higher tumor grade, loss of ER and the basal-like phenotype.
MiR-145 is a tumor suppressor which directly targets p70S6K1 for inhibiting its expression in pancreatic adenocarcinoma, providing new therapeutic scheme.
Finally, we demonstrate that expression of miR-145 in esophageal adenocarcinoma cell line (SK-GT-4) enhances tumor growth and metastasis in a NOD/SCID xenograft model.
More importantly, in a peritoneal mouse tumor model, the systemic administration of the R11-SSPEI/FAM-miR-145 complex leads to the delivery of miR-145 into the tumors, dramatically inhibiting tumor growth and prolonged survival time.
Together, these results suggest that miR-145 is a novel target of PPARγ, acts as a tumor suppressor in CRC cell lines and is a key regulator of intestinal cell differentiation by directly targeting SOX9, a marker of undifferentiated progenitors in the colonic crypts.
The Rho-associated protein kinase (ROCK1) has been found to act as key regulator of actin cytoskeleton reorganization, a process closely associated with cancer cell invasion. microRNA-145 (miRNA-145) has been recently shown to act as a suppressor in several types of tumor, including glioma.
High expression level of miR-21 in the serum was correlated with tumor size, grade of differentiation, invasion, metastasis and clinical stage, and low expression level of miR-145 in the serum was correlated with tumor size, grade of differentiation, invasion, metastasis and clinical stage.
Thus, this study identified GBC patient subgroups and provides new mechanistic insights in the tumor suppressive function of miR-145-5p leading to activation of STAT1 signaling.
These findings indicate that microRNA-145-5p functions as a novel tumor suppressor through targeting RAB18, suggesting that microRNA-145-5p might be a potential new therapeutic molecule for the treatment of hepatocellular carcinoma.
MicroRNAs (miRNAs) are a group of small, noncoding, regulatory RNAs with important roles in regulating gene expression. miR-145 is reported to be a key tumor suppressor miRNA (tsmiR) that controls important oncogenes, such as MYC and RAS.