During gestation, Toxoplasma gondii infection produces a series of complications including stillbirths, abortions, and congenital malformations. The inhibitory receptor, LILRB4, which is mainly expressed by professional antigen-presenting cells (especially macrophages and dendritic cells) may plays an important immune-regulatory role at the maternal–fetal interface. To assess the role of LILRB4 during T. gondii infection, LILRB4−/− and T. gondii infected pregnant mouse models were established. Further, human primary-decidual macrophages were treated with anti-LILRB4 neutralizing antibody and then infected with T. gondii. These in vivo and in vitro models were used to explore the role of LILRB4 in T. gondii-mediated abnormal pregnancy outcomes. The results showed that abnormal pregnancy outcomes were more prevalent in LILRB4−/− infected pregnant mice than in wild-type infected pregnant mice. In subsequent experiments, expression levels of LILRB4, M1, and M2 membrane functional molecules, arginine metabolic enzymes, and related cytokines were assessed in uninfected, infected, LILRB4 neutralized infected and LILRB4−/− infected models. The results demonstrated T. gondii infection to downregulate LILRB4 on decidual macrophages, which strengthened M1 activation functions and weakened M2 tolerance functions by changing M1 and M2 membrane molecule expression, synthesis of arginine metabolic enzymes, and cytokine secretion profiles. These changes contributed to abnormal pregnancy outcomes. The results of this study provide not only a deeper understanding of the immune mechanisms operational during abnormal pregnancy, induced by T. gondii infection, but also identify potential avenues for therapeutic and preventive treatment of congenital toxoplasmosis.

Resveratrol is a common, naturally occurring polyphenol confirmed with inhibited the cellular effects of carcinogenesis. However, the molecular mechanism underlying resveratrol's action against hepatocellular carcinoma (HCC) is still unclear. In addition, MARCH1 promotes the initiation and progression of HCC, but it is unclear whether resveratrol exerts antitumor efforts by regulating MARCH1 expression. This study determined the molecular mechanisms underlying the antitumor effects of resveratrol in HCC. Resveratrol induced apoptosis and inhibited the proliferation, migration, and invasion of HCC cell lines (HepG2 and Hep3B). In addition, it inhibited MARCH1 and phospho-protein kinase B (p-AKT) expression but upregulated the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) dose-dependently both in vitro and in vivo. MARCH1 knockdown by small interfering RNA (siRNA) also increased PTEN expression. Meanwhile, MK2206 (an AKT inhibitor) and bisperoxovanadium (BPV; a PTEN inhibitor) combined with resveratrol decreased MARCH1 expression more than the single-treatment HCC group. These results suggested that resveratrol affects the biological characteristics of HCC via downregulation of MARCH1 expression.

Background: The role of IGF binding protein 2 (IGFBP2) in cancer development is intriguing. Previously we identified IGFBP2 as an extrinsic factor that supports the activity of hematopoietic stem cells (HSCs). Methods and results: Here we investigated the role of IGFBP2 in in human leukemia cells and in the retroviral AML1-ETO9a transplantation acute myeloid leukemia (AML) mouse model. Results: IGFBP2 is highly expressed in certain human AML and acute lymphoblastic leukemia (ALL) cells. Inhibition of expression of endogenous IGFBP2 in human leukemia cells led to elevated apoptosis and decreased migration and, consistently, to decreased activation of AKT and other signaling molecules. We also studied the effects of IGFBP2 knockout in the retroviral AML1-ETO9a transplantation AML mouse model. The deletion of IGFBP2 in donor AML cells significantly decreased leukemia development in transplanted mice. Lack of IGFBP2 resulted in upregulation of PTEN expression and downregulation of AKT activation, in the mouse AML cells. The treatment of IGFBP2 deficient AML cells with a PTEN inhibitor restored the wild-type colony forming ability. The deletion of IGFBP2 also led to decreased AML infiltration into peripheral organs and tissues, suggesting that IGFBP2 is required for the migration of AML cells out of bone marrow. Conclusion: IGFBP2 is a critical cell-autonomous factor that promotes the survival and migration of acute leukemia cells.

Liver cancer is a very common and significant health problem. Therefore, powerful molecular targeting agents are urgently needed. Previously, we demonstrated that secalonic acid-F (SAF) suppresses the growth of hepatocellular carcinoma (HCC) cells (HepG2), but the other anticancer biological functions and the underlying mechanism of SAF on HCC are unknown. In this study, we found that SAF, which was isolated from a fungal strain in our lab identified as Aspergillus aculeatus, could inhibit the progression of hepatocellular carcinoma by targeting MARCH1, which regulates the PI3K/AKT/β-catenin and antiapoptotic Mcl-1/Bcl-2 signaling cascades. First, we confirmed that SAF reduced the proliferation and colony formation of HCC cell lines (HepG2 and Hep3B), promoted cell apoptosis, and inhibited the cell cycle in HepG2 and Hep3B cells in a dose-dependent manner. In addition, the migration and invasion of HepG2 and Hep3B cells treated with SAF were significantly suppressed. Western blot analysis showed that the level of MARCH1 was downregulated by pretreatment with SAF through the regulation of the PI3K/AKT/β-catenin signaling pathways. Moreover, knockdown of MARCH1 by small interfering RNAs (siRNAs) targeting MARCH1 also suppressed the proliferation, colony formation, migration, and invasion as well as increased the apoptotic rate of HepG2 and Hep3B cells. These data confirmed that the downregulation of MARCH1 could inhibit the progression of hepatocellular carcinoma and that the mechanism may be via PI3K/AKT/β-catenin inactivation as well as the downregulation of the antiapoptotic Mcl-1/Bcl-2. In vivo, the downregulation of MARCH1 by treatment with SAF markedly inhibited tumor growth, suggesting that SAF partly blocks MARCH1 and further regulates the PI3K/AKT/β-catenin and antiapoptosis Mcl-1/Bcl-2 signaling cascade in the HCC nude mouse model. Additionally, the apparent diffusion coefficient (ADC) values, derived from magnetic resonance imaging (MRI), were increased in tumors after SAF treatment in a mouse model. Taken together, our findings suggest that MARCH1 is a potential molecular target for HCC treatment and that SAF is a promising agent targeting MARCH1 to treat liver cancer patients.

Membrane‐associated RING‐CH‐1 (MARCH1) is a membrane‐anchored E3 ubiquitin ligase that is involved in a variety of cellular processes. MARCH1 was aberrantly expressed as a tumour promoter in ovarian cancer, but the signalling about the molecular mechanism has not yet been fully illuminated. Here, we first determined that MARCH1 was obviously highly expressed in human hepatocellular carcinoma samples and cells. In addition, our findings demonstrated that the proliferation, migration and invasion of hepatocellular carcinoma were suppressed, but the apoptosis was increased, as a result of MARCH1 knockdown by either siRNA targeting MARCH1 or pirarubicin treatment. Conversely, the proliferation, migration and invasion of hepatocellular carcinoma were obviously accelerated, and the apoptosis was decreased, by transfecting the MARCH1 plasmid to make MARCH1 overexpressed. Moreover, in vivo, the results exhibited a significant inhibition of the growth of hepatocellular carcinoma in nude mice, which were given an intra‐tumour injection of siRNA targeting MARCH1. Furthermore, our study concluded that MARCH1 functions as a tumour promoter, and its role was up‐regulated the PI3K‐AKT‐β‐catenin pathways both in vitro and in vivo. In summary, our work determined that MARCH1 has an important role in the development and progression of hepatocellular carcinoma and may be used as a novel potential molecular therapeutic target in the future treatment of hepatocellular carcinoma.

Toxoplasma gondii (T. gondii) is a ubiquitous intracellular protozoan parasite that causes adverse pregnancy outcomes. Its infection downregulates the Treg cell population and TGF-β level, which may contribute to adverse pregnancy outcomes. TGF-β plays a critical role in Treg cell development, but whether TGF-β treatment can affect the number and function of Treg cells and hence alleviate adverse pregnancy outcomes caused by T. gondii infection remains elusive. In this study, T. gondii-infected pregnant mice were treated with TGF-β or TGF-β-neutralizing antibody. The pregnancy outcomes were observed on gestational day 14. The numbers of Treg cells and pSmad3, PD-1, and CTLA-4 expression of Treg cells were analyzed by flow cytometry. Histological changes were assessed using HE staining, while IL-10 and TNF-α levels were measured using ELISA. The results indicated that TGF-β treatment improved the T. gondii-induced adverse pregnancy outcomes, with alleviation of hemorrhage, restoration of uterine spiral arteries of the placenta, and increased Treg cell numbers; meanwhile, TGF-β neutralization resulted in more serious adverse pregnancy outcomes, with serious hemorrhage, more dilated uterine spiral arteries, and decreased Treg cell numbers. pSmad3 expression in CD4+ cells and CTLA-4 and PD-1 levels on Treg cells were upregulated by TGF-β treatment, but downregulated by TGF-β neutralization. The ratio of IL-10/TNF-α also increased after TGF-β treatment, but decreased after TGF-β neutralization. Our data indicate that TGF-β treatment could improve adverse pregnancy outcomes caused by T. gondii infection by upregulating Treg cell differentiation and function via the TGF-β/Smad3 signaling pathway, but not the proliferation of Treg cells.