ABSTRACT
Lead (Pb) is ubiquitous in environment that accumulates in teeth and calcified tissues from where it releases gradually with aging and adversely affects dental health. This study aimed to determine the effect of Pb exposure on odontogenic differentiation potential of isolated human dental pulp stem cells and investigate the possible underlying epigenetic factors. In the absence of Pb exposure, stem cells displayed significant odontogenic markers including elevated Alkaline Phosphatase (ALP) activity, Alizarin red staining intensity, and increased expression of odontogenic DMP1 and DSPP genes. Exposure to 60 µM Pb resulted in reduced ALP activity and calcium deposition. Also, diminished expression of RUNX2, DMP1, and DSPP, as well as Wnt signaling mediators including WNT1, and ß-catenin were detected. The expression of Wnt signaling related microRNAs, miRNA-139-5p and miRNA-142-3p, on the other hand, were shown to have a significant increase. We concluded that Pb could adversely affect the odontogenic differentiation potential of dental pulp stem cell. The underlying mechanism might related to Pb-induced epigenetic dysregulation of WNT1/ß-catenin pathway-related miRNAs leading to down-regulation of Wnt/ß-catenin related odontogenic genes and eventually impaired odontogenic differentiation process.
Subject(s)
Lead , MicroRNAs , Stem Cells , Wnt Signaling Pathway , beta Catenin , Cell Differentiation , Cells, Cultured , Dental Pulp/metabolism , Humans , Lead/adverse effects , MicroRNAs/genetics , MicroRNAs/metabolism , Stem Cells/metabolism , beta Catenin/genetics , beta Catenin/metabolismABSTRACT
Hsa-miRNA-139-5p (miR-139-5p) has recently been discovered having anticancer efficacy in different organs. However, the role of miR-139-5p on lung cancer is still ambiguous. In this study, we investigated the role of miR-139-5p on development of lung cancer. Results indicated miR-139-5p was significantly down-regulated in primary tumor tissues and very low levels were found in a non-small cell lung cancer (NSCLC) cell lines. Ectopic expression of miR-139-5p in NSCLC cell lines significantly suppressed cell growth through inhibition of cyclin D1 and up-regulation of p57(Kip2). In addition, miR-139-5p induced apoptosis, as indicated by up-regulation of key apoptosis gene cleaved caspase-3, and down-regulation of anti-apoptosis gene Bcl2. Moreover, miR-139-5p inhibited cellular metastasis through inhibition of matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene c-Met was revealed to be a putative target of miR-139-5p, which was inversely correlated with miR-139-5p expression. Taken together, our results demonstrated that miR-139-5p plays a pivotal role in lung cancer through inhibiting cell proliferation, metastasis, and promoting apoptosis by targeting oncogenic c-Met.
Subject(s)
Apoptosis/genetics , Cell Proliferation/genetics , Down-Regulation , MicroRNAs/genetics , Proto-Oncogene Proteins c-met/genetics , Animals , Blotting, Western , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cyclin D1/genetics , Cyclin D1/metabolism , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mice, Inbred BALB C , Mice, Nude , Microscopy, Fluorescence , Proto-Oncogene Proteins c-met/metabolism , RNA Interference , Reverse Transcriptase Polymerase Chain Reaction , Survival Analysis , Tumor Burden/genetics , Xenograft Model Antitumor Assays/methodsABSTRACT
OBJECTIVES: MiRNA-139 is located at 11q13.4 and it has anti-oncogenic and antimetastatic activity in humans. However, its role in controlling apoptosis, invasion and metastasis and the development of chemosensitivity to docetaxel in breast cancer cells are not fully understood. The aim of this study was to research the biological function of miR-139-5p and the efficacy of chemosensitivity to docetaxel. METHODS: MiR-139-5p expression in MCF-7, MCF-7/Doc cells and in selected breast cancer tissue samples was confirmed by real-time PCR; cell viability was analyzed by Cell Counting Kit-8 assay; apoptosis and cell cycle were analyzed by flow cytometry; control of metastasis and invasion of breast cancer cells was measured by transwell assay; expression of Notch1 was measured by western blot; a luciferase reporter vector was constructed to identify the miR-139-5p target gene. RESULTS: MiR-139-5p was significantly down-regulated in breast cancer cells. MiR-139-5p inhibits the viability of breast cancer cells. MiR-139-5p induces apoptosis, causes cell cycle arrest in S phase, inhibits migration and invasion in breast cancer cells, however, MiR-139-5p play the opposite role in docetaxel-induced breast cancer cells. CONCLUSIONS: MiR-139-5p not only attenuated the development of breast cancer cells but also mediated drug-resistance by regulating the expression of the downstream target gene Notch1.