MicroRNA-93-5p increases multidrug resistance in human colorectal carcinoma cells by downregulating cyclin dependent kinase inhibitor 1A gene expression.

Multidrug resistance (MDR) impedes successful chemotherapy in colorectal carcinoma (CRC) and emerging evidence suggests that microRNAs (miRs) are involved in the development of MDR. In the present study, the role of miR-93-5p in the modulation of drug resistance in CRC was investigated using HCT-8 and MDR HCT-8/vincristine (VCR) cell lines. The results demonstrated upregulated expression of miR-93-5p and MDR protein 1 (MDR1) in HCT-8/VCR cells, compared with the parental HCT-8 cells. Furthermore, cyclin-dependent kinase inhibitor 1A (CDKN1A) was identified as a potential target of miR-93-5p using miR target analysis tools, including PicTar, TargetScan and miRanda. In addition, inhibition of miR-93-5p expression in HCT-8/VCR cells markedly downregulated MDR1 gene expression, upregulated CDKN1A gene expression and induced cell cycle arrest in G1. Conversely, the overexpression of miR-93-5p in HCT-8/VCR cells upregulated MDR1 gene expression, downregulated CDKN1A gene expression and promoted G1/S transition. Furthermore, the in vitro drug sensitivity assay performed suggested that downregulation of miR-93-5p enhanced the sensitivity of HCT-8/VCR cells to VCR, while the upregulation of miR-93-5p decreased the sensitivity of HCT-8 cells to VCR. In conclusion, the results of the present study suggest that miR-93-5p serves a role in the development of MDR through downregulating CDKN1A gene expression in CRC.

Transcriptome analysis of early organogenesis in human embryos.

Genome-wide expression analysis of embryonic development provides information that is useful in a variety of contexts. Here, we report transcriptome profiles of human early embryos covering development during the first third of organogenesis. We identified two major categories of genes, displaying gradually reduced or gradually increased expression patterns across this developmental window. The decreasing group appeared to include stemness-specific and differentiation-specific genes important for the initiation of organogenesis, whereas the increasing group appeared to be largely differentiation related and indicative of diverse organ formation. Based on these findings, we devised a putative molecular network that may provide a framework for the regulation of early human organogenesis. Our results represent a significant step in characterization of early human embryogenesis and provide a resource for understanding human development and for stem cell engineering.