BackgroundStudies have been shown that miR-125a plays an important role in carcinogenesis, however, the role of miR-125a in hepatocellular carcinoma (HCC) remains elusive.Methodology/PrincipalReal time-PCR (qRT-PCR) was performed to test the significance of miR-125a in HCC. Ectopic expression of miR-125a was used to test the influences of miR-125a on proliferation and metastasis of HCC cells in vitro and in vivo. Predicted target genes of miR-125a were determined by dual-luciferase reporting, qRT-PCR, and western blot (WB) analyses. Then immunohistochemical staining (IHC) was used to detect the expression of target genes, and the correlations and prognostic values of miR-125a and its target genes were also investigated.Conclusions/SignificanceDecreased miR-125a was observed in both HCC tissues and cell lines, and associated with patients’ aggressive pathologic features. Up-regulating miR-125a significantly inhibited the malignant phenotypes by repressing the expression of matrix metalloproteinase 11 (MMP11) and vascular endothelial growth factor A (VEGF-A) both in vitro and in vivo. Furthermore, miR-125a expression was inversely correlated with both MMP11 and VEGF-A expression in HCC tissues. Inhibiting miR-125a could increase both MMP11 and VEGF-A expression, and RNA interference targeting MMP11 or VEGF-A mRNA could rescue the loss of miR-125a functions. MiR-125a inhibits the proliferation and metastasis of HCC by targeting MMP11 and VEGF-A. Up-regulation of miR-125a might be a promising approach and a prognostic marker for HCC.

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Cancer stem cells (CSCs), or tumor initiating cells, are a subpopulation of cancer cells with self-renewal and differentiation properties. However, there has been no direct observation of the properties of gastric CSCs in vitro. Here we describe a vincristine (VCR)-preconditioning approach to obtain cancer stem-like cells (CSLCs) from the gastric cancer cell line SGC7901. The CSLCs displayed mesenchymal characteristics, including the up-regulated mesenchymal markers Snail, Twist, and vimentin, and the down-regulated epithelial marker E-cadherin. Using a Matrigel-based differentiation assay, CSLCs formed 2D tube-like and 3D complex lumen-like structures, which resembled differentiated gastric crypts. The characteristic of cellular differentiation was also found by transmission electron microscopy and up-regulation of gastrointestinal genes CDX2 and SOX2. We further showed that CSLCs could self-renew through significant asymmetric division compared with parent cells by tracing PKH-26, BrdU, and EDU label-retaining cells. In addition, these CSLCs also increased expression of CD44, CD90, and CXCR4 at the mRNA level, which was identified as novel targets. Furthermore, drug sensitivity assays and xenograft experiments demonstrated that the cells developed multi-drug resistance (MDR) and significant tumorigenicity in vivo. In summary, gastric CSCs were identified from VCR-preconditioned SGC7901 cell line, characterized by high tumorigenicity and the capacity for self-renewal and differentiation.

Gankyrin, a small and highly conserved protein which is identical to the p28 gene product, was found to be related with the malignant phenotypes in liver and esophageal carcinoma. However, the roles of gankyrin in colorectal carcinoma (CRC) are still unknown. In the present study, the gankyrin mRNA and protein expression in human CRC cell lines and clinical tissue samples were evaluated and correlated with clinicopathological features. Possible mechanisms by which gankyrin regulates the malignant phenotype of CRC cells were also investigated. The results demonstrated that gankyrin was obviously overexpressed in CRC tissues and cell lines compared to controls, and gankyrin expression was correlated with TNM stages and metastasis of CRC. Overexpression of gankyrin by PhkitNeo-hGankyrin plasmid transfected into Lovo cells could promote the cell proliferation and tumorigenicity. This finding was further strengthened by experiments that suppressing gankyrin expression by siRNA exerted the opposite effects on CRC cells SW620. In addition, our present study showed that the co-expression of cyclinD1 and beta-catenin were positive correlation with the alteration of gankyrin expression. This data suggested that gankyrin played significant roles in the pathogenesis of human CRC, and might be an important therapeutic target for CRC.