Caudatin suppresses adipogenesis in 3T3-L1 adipocytes and reduces body weight gain in high-fat diet-fed mice through activation of hedgehog signaling.

BACKGROUND: The regulative effects of caudatin, a C-21 steroid that is identified from Cynanchum bungee roots, on adipogenesis and obesity have not been studied. Many studies have demonstrated that the activation of hedgehog (Hh) signaling can help prevent obesity. Therefore, we hypothesized that caudatin can inhibit adipogenesis and obesity via activating the Hh signaling pathway. METHODS: To investigate the effects of caudatin on adipogenesis in 3T3-L1 preadipocytes and high-fat diet induced obesity in C57BL/6 mice, in vitro and in vivo experiments were performed. For in vitro evaluation, Oil red O staining were used to represent lipid accumulation in differentiated 3T3-L1 adipocytes. For in vivo assessment, male 5 week-old C57BL/6 mice were fed with standard chow diet, high-fat diet (HFD), HFD with 25 mg/kg caudatin, HFD with 1mg/kg purmorpharmine for 10 weeks, respectively. Hh signaling and key adipogenic marker involved in adipogenesis were evaluated by real-time PCR and western blot. The adipocyte size of white adopose tissue and lipid storage of liver were visualized by hematoxylin and eosin staining. In addition, the expression of Gli1 and peroxisome proliferator-activated receptor γ (PPARγ) in white adipose tissue were investigated by immunohistochemistry staining. RESULTS: Caudatin suppressed the accumulation of lipid droplets and downregulated the expression of key adipogenic factors, i.e., peroxisome proliferator-activated receptor γ PPARγ and CCAAT-enhancer binding protein α (C/EBPα), through activating Hh signaling in differentiated 3T3-L1 cells. Furthermore, caudatin and the Hh activator purmorpharmine significantly decreased body weight gain and white adipose tissue (WAT) weight in HFD-induced mice and affected adipogenic markers and Hh signaling mediators in WAT, which were in line with the in vitro experimental results. CONCLUSION: To our best knowledge, it is the first report to demonstrate that caudatin downregulated adipocyte differentiation and suppressed HFD-induced body weight gain through activating the Hh signaling pathway, suggesting that caudatin can potentially counteract obesity.

Garcinone C suppresses colon tumorigenesis through the Gli1-dependent hedgehog signaling pathway.

BACKGROUND: Although garcinone C, a natural xanthone derivative identified in the pericarp of Garcinia mangostana, has been demonstrated to exert different health beneficial activities in oxidative stress and ß-amyloid aggregation, the role of garcinone C in colon tumorigenesis has not been investigated. In addition, aberrant Hedgehog (Hh) signaling activation is associated with tumorigenesis including colon cancer. Here, we hypothesized that garcinone C can prevent colon tumorigenesis through regulating the Hh signaling pathway. METHOD: Colony formation assay and flow cytometry were used to evaluate the effect of garcinone C on the proliferation and cell cycle progression of colon cancer cells. Protein expression of cell cycle related markers and Hh/Gli1 signaling mediators were determined. The regulatory effect of orally administered garcinone C on the Hh/Gli1 signaling pathway and colon tumorigenesis was evaluated in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colon cancer animal model. RESULTS: Garcinone C suppressed the proliferation of colon cancer cells, induced G0/G1 cell cycle arrest, as well as regulated the expression of cell cycle-related markers such as cyclin D1, cyclin E, CDK6, and p21. Garcinone C inhibited the expression of Gli1, a key mediator of Hedgehog signaling, and protein kinase B (AKT) phosphorylation in Smo-independent colon cancer cells. In the AOM/DSS-induced colon tumorigenesis model, garcinone C significantly inhibited tumor development, regulated the expression of cell cycle markers and Gli1, and reduced AKT phosphorylation in colon tumor tissues, which is consistent with our in vitro results. CONCLUSION: Garcinone C can suppress colon tumorigenesis in vitro and in vivo through Gli1-dependent non-canonical Hedgehog signaling, suggesting that it may serve as a potent chemopreventive agent against colon tumorigenesis.

ß-Thujaplicin inhibits basal-like mammary tumor growth by regulating glycogen synthase kinase-3ß/ß-catenin signaling.

ß-Thujaplicin, a natural monoterpenoid, has been demonstrated to exert health beneficial activities in chronic diseases. However, it has not been studied in regulating estrogen receptor (ER) negative breast cancer. Here, we investigated the effect of ß-thujaplicin on inhibiting ER-negative basal-like breast cancer and the underlying mechanism of action using an in vitro and in vivo xenograft animal model. ß-Thujaplicin induced G0/G1 phase cell cycle arrest and regulated cell cycle mediators, cyclin D1, cyclin E, and cyclin-dependent kinase 4 (CDK 4), leading to the inhibition of the proliferation of ER-negative basal-like MCF10DCIS.com human breast cancer cells. It also modulated the phosphorylation of protein kinase B (AKT) and glycogen synthase kinase (GSK-3ß) and the protein level of ß-catenin. In an MCF10DCIS.com xenograft animal model, ß-thujaplicin significantly inhibited tumor growth, reduced tumor weight, and regulated the expression of cell cycle proteins, phosphorylation of AKT and GSK-3ß, and protein level of ß-catenin in the tumor tissues. These results demonstrate that ß-thujaplicin can suppress basal-like mammary tumor growth by regulating GSK-3ß/ß-catenin signaling, suggesting that ß-thujaplicin may be a potent chemopreventive agent against the basal-like subtype of breast cancer.

Promising preclinical platform for evaluation of immuno-oncology drugs using Hu-PBL-NSG lung cancer models.

BACKGROUND: With the advance of immunotherapy, treatment of non-small-cell lung cancer (NSCLC) has revolutionized by having anti-PD-1 therapy in front-line setting. In this era of cancer immunotherapy, humanized mouse models which recapitulate human immune system, are needed for predicting immunotherapy response in patients. We established a Hu-PBL-NSG mouse model which can be used as a preclinical testing platform for assessing efficacy of different immunotherapeutic agents. MATERIALS AND METHODS: Hu-PBL-NSG mouse model was established by engrafting human peripheral blood mononuclear cells (PBMCs) into NOD/scid/IL-2Rγ-/- (NSG) mice. Cytokine array was performed to assess serological similarity between patient and the Hu-PBL-NSG mouse, and microscopic immune cell infiltration was observed in various organs mouse model. Human anti-PD-1 therapy was treated for assessing drug efficacy in patient-derived tumor. RESULTS: hCD3+hCD45+ T-cells and antigen presenting cells (dendritic cells, macrophages, and MDSC) increased in the serum of Hu-PBL-NSG mouse 24 h after the transfusion of human PBMCs, and CD3 + T cells were observed in lung, liver, kidney, spleen sections. Cytokine arrays of human and Hu-PBL-NSG mouse revealed high similarity of Th1, Th2, Th17-related cytokines. A tumor xenograft was engrafted from an EML4-ALK patient, and Hu-PBL-NSG mouse was sacrificed for histological analyses. hCD3+ T cells were infiltrated within the tumor, and CD11c + cells, which represent antigen-presenting capability, were seen in spleen, lung, liver and kidney. When anti-PD-1 Ab was treated intraperitoneally, xenograft tumor showed significant reduction in volume after day 6, and increased expression of immune response-related genes on microarray analysis in the tumor. Mostly IFN-gamma and its related gene sets were significantly changed (FDR < 0.25, GSEA). CONCLUSION: Hu-PBL-NSG mouse model which highly resembles human immune system was successfully established. This model could be a strong preclinical model for testing efficacy of immunotherapeutic agents, and also for pursuing novel immunotherapy treatment strategies in advanced NSCLC.