Oncogenic gene RGC-32 is a direct target of miR-26b and facilitates tongue squamous cell carcinoma aggressiveness through EMT and PI3K/AKT signalling

Smoothened mediates medaka spermatogonia proliferation via Gli1-Rgcc-Cdk1 axis†

The proliferation of spermatogonia directly affects spermatogenesis and male fertility, but its underlying molecular mechanisms are poorly understood. In this study, Smoothened (Smo), the central transducer of Hedgehog signaling pathway, was characterized in medaka (Oryzias latipes), and its role and underlying mechanisms in the proliferation of spermatogonia were investigated. Smo was highly expressed in spermatogonia. In ex vivo testicular organ culture and a spermatogonial cell line (SG3) derived from medaka mature testis, Smo activation promoted spermatogonia proliferation, while its inhibition induced apoptosis. The expression of glioma-associated oncogene homolog 1 (gli1) and regulator of cell cycle (rgcc) was significantly upregulated in SG3 after Smo activation. Furthermore, Gli1 transcriptionally upregulated the expression of rgcc, and Rgcc overexpression rescued cell apoptosis caused by Smo or Gli1 inhibition. Co-immunoprecipitation assay indicated that Rgcc could interact with cyclin-dependent kinase 1 (Cdk1) to regulate the cell cycle of spermatogonia. Collectively, our study firstly reveals that Smo mediates the proliferation of spermatogonia through Gli1-Rgcc-Cdk1 axis. In addition, Smo and Gli1 are necessary of the survival of spermatogonia. This study deepens our understanding of spermatogonia proliferation and survival at the molecular level, and provides insights into male fertility control and reproductive disease treatment.

Nonylphenol Promoted Epithelial-Mesenchymal Transition in Colorectal Cancer Cells by Upregulating the Expression of Regulator of Cell Cycle

Nonylphenol (NP) is a widely used chemical, which has been considered a kind of endocrine-disrupting chemical and is involved in the occurrence and development of many types of cancers. Our recent studies demonstrated that NP exposure is related to colorectal cancer (CRC) progression. In this study, we also found epithelial-mesenchymal transition (EMT) promoted by NP treatment in CRC cells. However, the mechanism of NP on tumor metastasis is still unclear. In this study, we focused on the effect of the regulator of cell cycle (RGCC) induced by NP treatment. The cancer genome atlas (TCGA) analysis suggested that the expression of RGCC increased in CRC tissues, and our clinical samples showed that the expression of RGCC in tumor tissues is positively correlated with the serum level of NP in CRC patients. Further studies revealed that overexpression of RGCC could enhance the NP-induced EMT process in CRC cells and activate ERK signaling pathways. Inhibiting ERK signaling by ERK inhibitors or the knockdown of RGCC could attenuate the NP-induced EMT process. In addition, both RGCC overexpression and NP treatment could activate ERK pathways and attenuate the effect of ERK inhibitors on the EMT process in CRC cells. Altogether, this study demonstrated that NP could induce cell invasion and migration by increasing the expression of RGCC to enhance the EMT process, which might be through the activation of ERK signaling pathways. This finding supported a potential target for studying NP exposure-related colorectal cancers.

Bone Marrow Mesenchymal Stem Cells (BMSC)-Derived MicroRNA-189 Inhibits Glioma Tumorigenesis Through Suppressing Tumor Necrosis Factor-α (TNF-α)-Mediated Nuclear Factor Kappa Light Chain Enhancer of Activated B Cells (NF-κB) Signaling Pathway

This study aims at investigating the mechanism underlying bone marrow mesenchymal stem cells (BMSC) function in glioma. Glioma cells were administered with plasmids loading NF-κB siRNA, microRNA (miRNA)-189 inhibitor, or miR-189 mimics for transfection followed by analysis of miR-189 expression by RT-qPCR, cell apoptosis by flow cytometry, cell proliferation by MTT assay,invasion and migration by Transwell assay, inflammatory factors secretion by ELISA as well as proteins expression by western blot. A mouse model of glioma was established to detect the in vivo effect of BMSCs. miR-189 was lowly expressed in glioma cell lines but enriched in BMSCs. When miR-189 was silenced, cell proliferation, invasion and migration were potentiated and apoptosis was decreased, along with enhancement of N-cadherin, Vimentin, MMP-2 and and MMP-9, and decline in Bax, cleaved casepase-3 and cleaved PARP. Silencing of NF-κB reversed the effect of miR-189 inhibitor on cell progression, accompanied with reduction of inflammatory factors. BMSCs treatment effectively promoted miR-189 expression in glioma and inactivated TNF-α/NF-κB signaling, thereby suppressing tumor growth. In conclusion, miR-189 derived from BMSC inhibits glioma progression through regulation of TNF-α/NF-κB signaling pathway.