The roles of Wnt/β-catenin signaling pathway related lncRNAs in cancer

DKK1 inhibits breast cancer cell migration and invasion through suppression of β-catenin/MMP7 signaling pathway

Background

DKK1 has been reported to act as a tumor suppressor in breast cancer. However, the mechanism of DKK1 inhibits breast cancer migration and invasion was still unclear.

Methods

Western blot and real time PCR was used to detect the expression of DKK1, β-catenin and MMP7 in breast cancer cells. Wound scratch assay and transwell assay was employed to examine migration and invasion of breast cancer cell.

Results

DKK1 overexpression dramatically inhibits breast cancer cell migration and invasion. Knockdown of DKK1 promotes migration and invasion of breast cancer cells. DKK1 suppressed breast cancer cell migration and invasion through suppression of β-catenin and MMP7 expression. XAV-939, an inhibitor of β-catenin accumulation could reverse DKK1 silencing-induced MMP7 expression in breast cancer cells. Meanwhile, XAV-939 also could reverse the increase in the cell number invaded through Matrigel when DKK1 was knockdown. Furthermore, depletion of MMP7 also could reverse DKK1 knockdown-induced increase in the cell number invaded through Matrigel.

Conclusions

DKK1 inhibits migration and invasion of breast cancer cell through suppression of β-catenin/MMP7 pathway, our findings offered a potential alternative for breast cancer prevention and treatment.

Long noncoding RNA DLX6-AS1 targets miR-124-3p/CDK4 to accelerate Ewing's sarcoma

Ewing's sarcoma is one of leading cause of malignancy occurred in the children and adolescents worldwide. Given the emerging critical role of long noncoding RNA (lncRNA) in the human cancer, as well as Ewing's sarcoma, we aim to identify the biological role of DLX6-AS1 in the tumorigenesis. Results unveil that DLX6-AS1 expression was increased in the tissue sample and cells. Functionally, the silencing of DLX6-AS1 could repress the proliferation and accelerate the apoptosis of Ewing's sarcoma cells. Mechanically, DLX6-AS1 functioned as the sponge of miR-124-3p, and then miR-124-3p targeted the 3'-UTR of CDK4 mRNA, forming the DLX6-AS1/miR-124-3p/CDK4 regulatory pathway. In conclusion, the critical role of DLX6-AS1 might unveil a potential therapeutic target for Ewing's sarcoma.

Ganoderma lucidum Exerts an Anticancer Effect on Human Osteosarcoma Cells via Suppressing the Wnt/β-Catenin Signaling Pathway

Background: Current treatment of osteosarcoma is limited in part by side effects and low tolerability, problems generally avoided with traditional Chinese medicine. Ganoderma lucidum, a traditional Chinese medicine with antitumor effects, offers a potential alternative, but little is known about its molecular mechanisms in osteosarcoma cells. Objective: To investigate the effect of G lucidum on osteosarcoma cells and its mechanism. Methods: Osteosarcoma MG63 and U2-OS cells were treated with G lucidum, followed by assays for cell proliferation (Cell Counting Kit-8), colony formation, and apoptosis (Alexa Fluor 647-Annexin V/propidium iodide, flow cytometry). Migration and invasion of cells were assessed by wound healing and Transwell invasion assays, and the effect of G lucidum on Wnt/β-catenin signal transduction was studied by real-time quantitative polymerase chain reaction, western blot, and dual-luciferase assay. Results:G lucidum inhibited the proliferation, migration, and invasion, and induced apoptosis of human osteosarcoma MG63 and U2-OS cells. Dual-luciferase assay showed that G lucidum suppressed the transcriptional activity of T-cell factor/lymphocyte enhancer factor in the Wnt/β-catenin signaling pathway. Moreover, G lucidum blocked Wnt/β-catenin signaling by inhibiting the Wnt co-receptor LRP5 and Wnt-related target genes, such as β-catenin, cyclin D1, C-Myc, MMP-2, and MMP-9. At the same time, when Wnt/β-catenin was inhibited, the expression of E-cadherin was upregulated. Conclusions: Our results suggest that G lucidum broadly suppresses osteosarcoma cell growth by inhibiting Wnt/β-catenin signaling.