Background The novel coronavirus disease (2019-nCoV) has been affecting global health since the end of 2019 and there is no sign that the epidemic is abating . The major issue for controlling the infectious is lacking efficient prevention and therapeutic approaches. Chloroquine (CQ) and Hydroxychloroquine (HCQ) have been reported to treat the disease, but the underlying mechanism remains controversial. Purpose The objective of this study is to investigate whether CQ and HCQ could be ACE2 blockers and used to inhibit 2019-nCoV virus infection. Methods In our study, we used CCK-8 staining, flow cytometry and immunofluorescent staining to evaluate the toxicity and autophagy of CQ and HCQ, respectively, on ACE2 high-expressing HEK293T cells (ACE2 h cells). We further analyzed the binding character of CQ and HCQ to ACE2 by molecular docking and surface plasmon resonance (SPR) assays, 2019-nCoV spike pseudotyped virus was also used to observe the viropexis effect of CQ and HCQ in ACE2 h cells. Results Results showed that HCQ is slightly more toxic to ACE2 h cells than CQ. Both CQ and HCQ could bind to ACE2 with K D = (7.31 ± 0.62) e −7 M and (4.82 ± 0.87) e −7 M, respectively. They exhibit equivalent suppression effect for the entrance of 2019-nCoV spike pseudotyped virus into ACE2 h cells. Conclusions CQ and HCQ both inhibit the entrance 2019-nCoV into cells by blocking the binding of the virus with ACE2. Our findings provide novel insights into the molecular mechanism of CQ and HCQ treatment effect on virus infection.

Chlorogenic acid (CGA), which is a natural compound found in various plants, has been reported to exert notable anti‑inflammatory activities. The present study investigated the effects and underlying mechanism of CGA on interleukin (IL)‑1β‑induced osteoarthritis (OA) chondrocytes. An in vitro OA‑like chondrocyte model was established using IL‑1β‑stimulated human SW‑1353 chondrocytes. Cell viability was assessed using an MTT assay. Nitric oxide (NO) and IL‑6 production were evaluated by Griess reaction and ELISA, respectively. The expression levels of inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2), cyclooxygenase 2 (COX‑2), collagen II, matrix metalloproteinase (MMP)‑13, p65 nuclear factor (NF)‑κB and inhibitor‑κBα were detected by western blot analysis. The results indicated that CGA reversed IL‑1β‑induced increases in iNOS/NO, IL‑6, MMP‑13 and COX‑2/PGE2 production, and reversed the IL‑1β‑mediated downregulation of collagen II. In addition, the data suggested that CGA was capable of inhibiting the IL‑1β‑induced inflammatory response, at least partially via the NF‑κB signaling pathway. In conclusion, CGA may be considered a suitable candidate agent in the treatment of OA.

Epithelial–mesenchymal transition (EMT) plays a crucial role in hepatocellular carcinoma (HCC) progression. Hypoxia and excessive transforming growth factor-β (TGF-β) have been identified as inducers and target for EMT in HCC. Here, we show hypoxia inducible factor-1α (HIF-1α) and TGF-β form a feed-forward loop to induce EMT in HCC cells. Further mechanistic study indicates under both hypoxia and TGF-β stimulation, Smad and PI3K-AKT pathways are activated. We show sanguinarine, a natural benzophenanthridine alkaloid, impairs the proliferation of nine kinds of HCC cell lines and the colony formation of HCC cells. In hypoxic and TGF-β cell models, sanguinarine inhibits HIF-1α signaling and the expression of EMT markers, translocation of Snail and activation of both Smad and PI3K-AKT pathways. Sanguinarine could also inhibit TGF-β-induced cell migration in HCC cells. In vivo studies reveal that the administration of sanguinarine inhibits tumor growth and HIF-1α signaling, inhibits the expression changes of EMT markers as well as Smad and PI3K-AKT pathway proteins. Our findings suggest that sanguinarine is a promising candidate targeting HIF-1α/TGF-β signaling to improve the treatment for HCC patients.

Colorectal cancer represents the fourth commonest malignancy, and constitutes a major cause of significant morbidity and mortality among other diseases. However, the chemical therapy is still under development. Angiogenesis plays an important role in colon cancer development. We developed HMQ18–22 (a novel analog of taspine) with the aim to target angiogenesis. We found that HMQ18–22 significantly reduced angiogenesis of chicken chorioallantoic membrane (CAM) and mouse colon tissue, and inhibited cell migration and tube formation as well. Then, we verified the interaction between HMQ18–22 and VEGFR2 by AlphaScreen P-VEGFR assay, screened the targets on angiogenesis by VEGF Phospho Antibody Array, validated the target by western blot and RNAi in lovo cells. We found HMQ18–22 could decrease phosphorylation of VEGFR2(Tyr1214), VEGFR1(Tyr1333), Akt(Tyr326), protein kinase Cα (PKCα) (Tyr657) and phospholipase-Cγ-1 (PLCγ-1) (Tyr771). Most importantly, HMQ18–22 inhibited proliferation of lovo cell and tumor growth in a human colon tumor xenografted model of athymic mice. Compared with normal lovo cells proliferation, the inhibition on proliferation of knockdown cells (VEGFR2, VEGFR1, Akt, PKCα and PLCγ-1) by HMQ18–22 decreased. These results suggested that HMQ18–22 is a novel angiogenesis inhibitor and can be a useful therapeutic candidate for colon cancer intervention.

Hepatocellular carcinoma (HCC) is a biologically complex disease. Combination chemotherapy is a good strategy after surgery treatment. In this study, we report that berberine combined with HMQ1611 (BCH) had a good synergistic effect on the HCC. Our findings concluded that BCH showed good inhibition on the HCC proliferation and colony formation, which attributed to cell cycle arrest by BCH at G1 phase through impairing the expression of cyclinD1, cyclinE, and cdc2 and downregulated the phosphorylation of Akt, mTOR, and ERK. Moreover, BCH negatively regulated Wnt signaling pathway by upregulating the Axin and inhibiting the nuclear translocation of β‐catenin. BCH suppressed the phosphorylation of LRP5/6, GSK3β, the expression of Wnt5a, Frizzled8, CK1, and APC, as well as the nucleus protein included MMP2, MMP3, MMP9, and c‐myc. The above data of Wnt signaling regulators contributed to inhibition by BCH on cell migration. In vivo studies, BCH significantly suppressed the growth of SMMC‐7721 xenograft tumors through downregulating Ki67 and β‐catenin, as well as upregulating Axin and p‐β‐catenin. In conclusion, the results revealed that BCH exhibited potential antitumor activities against human liver cancer in vitro and in vivo, and the potential mechanism underlying these activities depended on the inhibition of the Wnt/β‐catenin signaling pathway.