Osteoporosis is an osteolytic disease that features enhanced osteoclast formation and bone resorption. Identification of agents that can inhibit osteoclast formation and function is important for the treatment of osteoporosis. Dihydroartemisinin is a natural compound used to treat malaria but its role in osteoporosis is not known. Here, we found that dihydroartemisinin can suppress RANKL-induced osteoclastogenesis and bone resorption in a dose-dependent manner. Dihydroartemisinin inhibited the expression of osteoclast marker genes such as cathepsin K, calcitonin receptor, and tartrate-resistant acid phosphatase (TRAcP). Furthermore, dihydroartemisinin inhibited RANKL-induced NF-kB and NFAT activity. In addition, using an in vivo ovariectomized mouse model, we show that dihydroartemisinin is able to reverse the bone loss caused by ovariectomy. Together, this study shows that dihydroartemisinin attenuates bone loss in ovariectomized mice through inhibiting RANKL-induced osteoclast formation and function. This indicates that dihydroartemisinin, the first physiology or medicine nobel prize discovery of China, is a potential treatment option against osteolytic bone disease.

Background: Mdm2 oncogene expression is regulated by p53-dependent and -independent mechanisms. Results: The NFAT1 transcription factor binds to the mdm2 P2 promoter and transactivates mdm2 independent of p53. Conclusion: NFAT1 is a transcriptional activator of the mdm2 oncogene. Significance: The identification of p53-independent control of mdm2 expression by NFAT1 will increase the understanding of the roles of NFAT1 in cancer.

Overexpression of the MDM2 oncogene and mutations in the p53 tumor suppressor commonly occur in hepatocellular carcinoma (HCC) and are associated with increased mortality due to this disease. Inhibiting MDM2 has been demonstrated to be a valid approach for the treatment of HCC. However, most of the MDM2 inhibitors evaluated to date have been designed to block the MDM2 and p53 binding, and have limited efficacy against tumors with mutant or deficient p53. In the present study, we developed a novel MDM2 inhibitor (termed SP141) that has direct effects on MDM2 and exerts anti-HCC activity independent of the p53 status of the cancer cells. We demonstrate that SP141 inhibits cell growth and prevents cell migration and invasion, independent of p53. Mechanistically, SP141 directly binds the MDM2 protein and promotes MDM2 degradation. The inhibition of MDM2 by SP141 also increases the sensitivity of HCC cells to sorafenib. In addition, in orthotopic and patient-derived xenograft models, SP141 inhibits MDM2 expression and suppresses tumor growth and metastasis, without any host toxicity. Furthermore, the inhibition of MDM2 by SP141 is essential for its anti-HCC activities. These results provide support for the further development of SP141 as a lead candidate for the treatment of HCC.

RYBP is a member of the polycomb group (PcG) proteins that typically act as transcriptional repressors via epigenetic modification of chromatin. The present study was designed to investigate the role of RYBP in HCC progression, chemosensitivity, and patient survival, and to explore the underlying molecular mechanism(s). In this study we investigated the expression of RYBP in 400 pairs of human HCC tissues and matched noncancerous samples. The effects of RYBP on HCC tumor growth and metastasis and chemosensitivity were determined both in vitro and in vivo. We herein demonstrate that the RYBP expression in HCC tissue samples was significantly lower than that in matched noncancerous liver tissues. Clinically, the low expression of RYBP was an independent predictor of a poor prognosis in patients with HCC. In in vitro HCC models, enforced RYBP expression inhibited cell growth and invasion, induced apoptosis, and increased the chemosensitivity of the cells, while RYBP knockdown led to the opposite effects. Furthermore, RYBP expression was induced by cisplatin, and adenovirus-mediated RYBP expression inhibited HCC tumor growth and sensitized HCC to conventional chemotherapy in vivo. Our results demonstrate that reactivating RYBP in cancer cells may provide an effective and safe therapeutic approach to HCC therapy.

Intrahepatic cholangiocarcinoma (ICC) is a malignant tumor derived from bile duct epithelium. Its characteristics include an insidious onset and frequent recurrence or metastasis after surgery. Current chemotherapies and molecular target therapies provide only modest survival benefits to patients with ICC. Anlotinib is a novel multi-target tyrosine kinase inhibitor that has good antitumor effects in a variety of solid tumors. However, there are few studies of anlotinib-associated mechanisms and use as a treatment in ICC. In this study using in vitro experiments, we found that anlotinib had significant effects on proliferation inhibition, migration and invasion restraint, and cell-cycle arrestment. Anlotinib treatment affected induction of apoptosis and the mesenchymal-epithelial transition. Patient-derived xenograft models generated directly from patients with ICC revealed that anlotinib treatment dramatically hindered in vivo tumor growth. We also examined anlotinib's mechanism of action using transcriptional profiling. We found that anlotinib treatment might mainly inhibit tumor cell proliferation and invasion and promote apoptosis via cell-cycle arrestment by inactivating the VEGF/PI3K/AKT signaling pathway, as evidenced by significantly decreased phosphorylation levels of these kinases. The activation of vascular endothelial growth factor receptor 2 (VEGFR2) can subsequently activate PI3K/AKT signaling. We identified VEGRF2 as the main target of anlotinib. High VEGFR2 expression might serve as a promising indicator when used to predict a favorable therapeutic response. Taken together, these results indicated that anlotinib had excellent antitumor activity in ICC, mainly via inhibiting the phosphorylation level of VEGFR2 and subsequent inactivation of PIK3/AKT signaling. This work provides evidence and a rationale for using anlotinib to treat patients with ICC in the future.

Osteoarthritis (OA) is a degenerative illness that greatly impacts the life quality of patients. Currently, the therapeutic approaches for OA are very limited in clinical. The extracellular vesicles (EVs) derived from different mesenchymal stem cells displayed a prominent therapeutic effect on OA. But most EVs have limited resources and the risks of host rejection, immunological response, and etc. Human umbilical cord mesenchymal stem cells (hUCMSCs) hold the advantages of easy availability, minimal immune rejection, and excellent immunomodulatory effects, although hUCMSCs-EVs have seldom been applied in OA. Herein, we investigated the potential immunomodulatory and anti-inflammatory effects of hUCMSCs-EVs on the treatment of OA. In our results, the treatment of hUCMSCs-EVs promoted the polarization of M2-type macrophages and the expression of anti-inflammation-related cytokines (IL-10). Notably, the supernate of M2 macrophages induced by hUCMSCs-EVs inhibited the level of inflammation-associated factors in OA chondrocytes caused by IL-1β. Further, injection of hUCMSCs-EVs in the articular lumen ameliorated progression of OA and exerted chondroprotective potential based on the OA joint model created by the surgical transection of the anterior cruciate ligament (ACLT). In addition, we found five highly enriched miRNAs in hUCMSCs-EVs, including has-miR-122-5p, has-miR-148a-3p, has-miR-486-5p, has-miR-let-7a-5p, and has-miR-100-5p by High-throughput sequencing of miRNAs, with targeted genes mainly enriched in the PI3K-Akt signaling pathway. Furthermore, we also detected the protein abundance of hUCMSCs-EVs using liquidation chromatography with tandem quadrupole mass spectrometry (LC–MS/MS) analysis. Thus, our study indicates that hUCMSCs-EVs can alleviate cartilage degradation during the OA progression, mechanically may through delivering key proteins and modulating the PI3K-Akt signaling pathway mediated by miRNAs to promote polarization of M2 macrophage, exhibiting potent immunomodulatory potential. The current findings suggest that hUCMSCs-EVs might serve as a new reagent for the therapy of OA. Graphical Abstract

Highlights • CD13 expression is higher in more metastatic HCC samples and its overexpression predicts worse prognosis in HCC patients. • CD13 regulates HCC cell proliferation, invasion, primary tumor growth and sorafenib resistance. • CD13-HDAC5-LSD1-NF-#x003BA;B signaling axis is a newly identified signaling axis in HCC. • CD13 inhibitor Ubenimex restored sorafenib sensitivity in HCC.

Over-production and activation of osteoclasts is a common feature of osteolytic conditions such as osteoporosis, tumor-associated osteolysis, and inflammatory bone erosion. Cyanidin Chloride, a subclass of anthocyanin, displays antioxidant and anti-carcinogenesis properties, but its role in osteoclastic bone resorption and osteoporosis is not well understood. In this study, we showed that Cyanidin Chloride inhibits osteoclast formation, hydroxyapatite resorption, and receptor activator of NF-κB ligand (RANKL)-induced osteoclast marker gene expression; including ctr, ctsk, and trap. Further investigation revealed that Cyanidin Chloride inhibits RANKL-induced NF-κB activation, suppresses the degradation of IκB-α and attenuates the phosphorylation of extracellular signal-regulated kinases (ERK). In addition, Cyanidin Chloride abrogated RANKL-induced calcium oscillations, the activation of nuclear factor of activated T cells calcineurin-dependent 1 (NFATc1), and the expression of c-Fos. Further, we showed that Cyanidin Chloride protects against ovariectomy-induced bone loss in vivo. Together our findings suggest that Cyanidin Chloride is capable of inhibiting osteoclast formation, hydroxyapatite resorption and RANKL-induced signal pathways in vitro and OVX-induced bone loss in vivo, and thus might have therapeutic potential for osteolytic diseases.