A CD10-OGP Membrane Peptolytic Signaling Axis in Fibroblasts Regulates Lipid Metabolism of Cancer Stem Cells via SCD1.

Carcinoma-associated fibroblasts (CAFs) consist of heterogeneous subpopulations that play a critical role in the dynamics of the tumor microenvironment. The extracellular signals of CAFs have been attributed to the extracellular matrix, cytokines, cell surface checkpoints, and exosomes. In the present study, it is demonstrated that the CD10 transmembrane hydrolase expressed on a subset of CAFs supports tumor stemness and induces chemoresistance. Mechanistically, CD10 degenerates an antitumoral peptide termed osteogenic growth peptide (OGP). OGP restrains the expression of rate-limiting desaturase SCD1 and inhibits lipid desaturation, which is required for cancer stem cells (CSCs). Targeting CD10 significantly improves the efficacy of chemotherapy in vivo. Clinically, CD10-OGP signals are associated with the response to neoadjuvant chemotherapy in patients with breast cancer. The collective data suggest that a nexus between the niche and lipid metabolism in CSCs is a promising therapeutic target for breast cancer.

Environmental Pollutant Benzo[a]pyrene Upregulated Long Non-coding RNA HZ07 Inhibits Trophoblast Cell Migration by Inactivating PI3K/AKT/MMP2 Signaling Pathway in Recurrent Pregnancy Loss.

Benzo(a)pyrene (BaP) is a ubiquitous environmental endocrine-disrupting chemical that is known to have toxic effects on reproduction. However, the underlying mechanisms describing how BaP and its metabolite benzo[a]pyrene-7, 8-diol-9, 10-epoxide (BPDE) induce recurrent pregnancy loss (RPL) are still largely unclear. In this study, we identified a novel long non-coding RNA (lnc-HZ07, NCBI MT936329) that was upregulated in trophoblast cells after exposure to BPDE, and lnc-HZ07 expression was significantly higher in RPL villous tissues than that in control villous tissues. Knockdown of lnc-HZ07 promoted trophoblast cell migration, whereas overexpression of lnc-HZ07 inhibited trophoblast cell migration. Further study showed that lnc-HZ07 inhibited trophoblast migration by downregulating matrix metalloproteinase 2 (MMP2) expression via dephosphorylation of AKT. These results demonstrated a novel regulatory pathway in which BaP downregulated AKT phosphorylation and inhibited MMP2 expression by upregulating lnc-HZ07, suggesting that lnc-HZ07 could be considered as a potential pathological marker of BaP-induced RPL and therapeutic target for this disease.

LNK promotes granulosa cell apoptosis in PCOS via negatively regulating insulin-stimulated AKT-FOXO3 pathway.

BACKGROUND: Polycystic ovary syndrome (PCOS), which is often accompanied by insulin resistance, is closely related to increased apoptosis of ovarian granulosa cells. LNK is an important regulator of the insulin signaling pathway. When insulin binds to the receptor, the PI3K/AKT/FOXO signaling pathway is activated, and FOXO translocates from the nucleus to the cytoplasm, thereby inhibiting the expression of pro-apoptotic genes. METHODS: Granulosa cells were collected from PCOS patients to investigate the relationship between LNK, cell apoptosis and insulin resistance. KGN cells underwent LNK overexpression/silence and insulin stimulation. The AKT/FOXO3 pathway was studied by western blot and immunofluorescence. LNK knockout mice were used to investigate the effect of LNK on the pathogenesis of PCOS. RESULTS: The level of LNK was higher in PCOS group than control group. LNK was positively correlated with granulosa cell apoptosis and insulin resistance, and negatively correlated with oocyte maturation rate. LNK overexpression in KGN cells inhibited insulin-induced AKT/FOXO3 signaling pathway, causing nucleus translocation of FOXO3 and promoting granulosa cell apoptosis. LNK knockout partially restored estrous cycle and improved glucose metabolism in PCOS mice. CONCLUSIONS: LNK was closely related to insulin resistance and apoptosis of granulosa cells via the AKT/FOXO3 pathway. LNK knockout partially restored estrous cycle and improved glucose metabolism in PCOS mice, suggesting LNK might become a potential biological target for the clinical treatment of PCOS.

Neutrophil and Neutrophil-to-Lymphocyte Ratio as Clinically Predictive Risk Markers for Recurrent Pregnancy Loss.

We aimed at exploring the value of neutrophil and neutrophil-to-lymphocyte ratio (NLR) as predictive risk markers for recurrent pregnancy loss (RPL) by conducting a retrospective case-control study and a systematic review and meta-analysis. This retrospective case-control study was conducted in an academic hospital from January 2012 to June 2018 and 133 cases of women with RPL and 140 control women. In parallel, we conducted a systematic review and meta-analysis on the value of NLR and neutrophil in RPL risk assessment. Neutrophil and NLR were higher in the women with RPL than those in the controls (median [interquartile range]: 4.32 [3.31-6.18] vs. 3.76 [2.78-4.81], p = 0.001; 2.17 [1.47-3.16] vs. 1.74 [1.40-2.34], p = 0.001). After the cut-off value of the neutrophil and NLR was determined to be 6.3 × 109/L and 3.16, the prevalence of RPL became significantly increased in the high-neutrophil and the high-NLR group compared to the low-neutrophil and the low-NLR group (76.3% vs. 44.2%, p < 0.001; 66.6% vs. 44.5%, p < 0.001). Univariate logistic regression analysis indicated that high-neutrophil and high-NLR were risk factors for RPL, with ORs of 4.06 (95% CI: 1.84-8.95) and 2.49 (95% CI: 1.31-4.71), respectively. Multivariate logistic regression analysis indicated that high-neutrophil was a risk factor for RPL, with OR of 4.91 (95% CI: 1.66-14.50). Meta-analysis of 5 case-control studies (including the present study) indicated that increased neutrophil and NLR may be risk factors for RPL, with SMDs of 0.63 (95% CI: 0.45-0.80) and 0.61 (95% CI: 0.39-0.83). Based on current findings and the meta-analysis, this study indicated that neutrophil and NLR might be valuable for predicting RPL; more studies with large sample are needed to verify this conclusion. The mechanism of the association between neutrophil and RPL needs to be explored in further studies.

Immunity and coagulation and fibrinolytic processes may reduce the risk of severe illness in pregnant women with coronavirus disease 2019.

BACKGROUND: There are specific physiological features regarding the immunity and coagulation among pregnant women, which may play important roles in the development of coronavirus disease 2019. OBJECTIVE: This study aimed to determine the key factors associated with the deterioration of patients with coronavirus disease 2019 and the differentiating clinical characteristics of pregnant women with coronavirus disease 2019 to interfere with the progression of coronavirus disease 2019. STUDY DESIGN: A retrospective study of 539 Chinese Han adult patients with coronavirus disease 2019 was conducted, of which 36 cases were pregnant women. In addition, 36 pregnant women without coronavirus disease 2019 were recruited as the control. The characteristics of severe and critical illnesses, which were differentiated from mild and moderate illnesses in patients with coronavirus disease 2019, were analyzed using a machine learning algorithm. In addition, major differences between pregnant women with coronavirus disease 2019 and age-matched nonpregnant women with severe or critical coronavirus disease 2019, paired with pregnant women without coronavirus disease 2019, were explored to identify specific physiological features of pregnant women with coronavirus disease 2019. RESULTS: For the total patient population, the lymphocyte, CD3+, CD4+, CD8+, CD19+, and CD16+CD56+ cell counts were significantly lower, and white blood cell count, neutrophil count, and neutrophil-to-lymphocyte ratio were higher in those with severe or critical illness than those with mild or moderate illness (P<.001). The plasma levels of interleukin-6, interleukin-10, and interleukin-6-to-interleukin-10 ratio were significantly increased in patients with critical illness compared with patients with mild, moderate, and severe illnesses (P<.001). The above immunologic coclusters achieved an area under the receiver operating characteristic curve of 0.801 (95% confidence interval, 0.764-0.838), and its combined model with the coagulation and fibrinolysis indices (prothrombin time, D-dimer) achieved an area under the receiver operating characteristic curve of 0.815 (95% confidence interval, 0.779-0.851) using the random forest regression model to predict severe or critical illness. For pregnant women with coronavirus disease 2019, none had preexisting diseases. Compared with nonpregnant women with mild or moderate coronavirus disease 2019, pregnant women with coronavirus disease 2019 displayed increased white blood cell count, neutrophil count, neutrophil-to-lymphocyte ratio, and levels of D-dimer and fibrinogen, along with decreased lymphocyte and interleukin-4 levels (P<.05). Although they presented similar changes of immunologic markers of lymphocyte; white blood cell count; neutrophil-to-lymphocyte ratio; CD3+, CD4+, CD8+, and CD16+CD56+ cell counts; and interleukin-6-to-interleukin-10 ratio, compared with nonpregnant women with severe or critical coronavirus disease 2019, none of the pregnant women with coronavirus disease 2019 deteriorated into severe or critical illness. There was no significant difference in white blood cell count, lymphocyte count, neutrophil count, neutrophil-to-lymphocyte ratio, immunologic markers, or coagulation and fibrinolysis markers between pregnant women with coronavirus disease 2019 and pregnant women without coronavirus disease 2019. As for the discrepancy of pathophysiological features between pregnant women with coronavirus disease 2019 and nonpregnant women with severe or critical coronavirus disease 2019, the immunologic markers achieved an area under the receiver operating characteristic curve of 0.875 (95% confidence interval, 0.773-0.977), and its combined model with coagulation and fibrinolysis indices achieved an area under the receiver operating characteristic curve of 0.931 (95% confidence interval, 0.850-1.000). CONCLUSION: Immune dysregulation was identified as a crucial feature of patients with coronavirus disease 2019, which developed severe or critical illness, and pregnant women with coronavirus disease 2019 presented with similar immune responses but rarer incidences of severe or critical illness. Immune dysregulation is related to the risks of deterioration into severe or critical illness. The specific coagulation and fibrinolysis systems of pregnancy may reduce the risk of pregnant women with coronavirus disease 2019 without preexisting disease from developing severe illness.

Environmental Pollutant Benzo[a]pyrene Induces Recurrent Pregnancy Loss through Promoting Apoptosis and Suppressing Migration of Extravillous Trophoblast.

METHODS: The implantation sites, fetus resorption, and abnormal fetuses were studied in pregnant mice treated with different doses of BaP by oral gavage from day 1 to day 10 of gestation. Additionally, apoptosis and related signaling pathway, and the migration and invasion of trophoblasts, were assessed before and after exposure of BPDE in Swan 71 trophoblast cell. Besides, the migration and invasion, and its related signaling pathway, were assessed in villi obtained from women. RESULTS: We observed a concentration-dependent incidence of abnormal murine fetuses, beginning with 0.1 mg/kg BaP; with a BaP concentration of 2 mg/kg, no fetuses developed. Correspondingly, a BPDE concentration-dependent apoptosis of human trophoblasts. Beginning with 0.5 µM BPDE exposure, Bax/Caspase-3 were increased and Bcl-2 decreased. Furthermore, BPDE also inhibited, in a dose-dependent manner, the migration of villous explants from elective abortion women, consistent with the reduced migration of villous explants from women with recurrent pregnancy loss (RPL), and reduced the cell immigration in Swan 71 trophoblasts, in a dose-dependent manner measured by transwell assays. CONCLUSIONS: Our study results provide mechanistic insight to the effect of BPDE on trophoblast dysfunction through enhanced cell apoptosis and inhibited migration, providing further experimental evidence to the causative links between BaP exposure and PRL.

LNK deficiency decreases obesity-induced insulin resistance by regulating GLUT4 through the PI3K-Akt-AS160 pathway in adipose tissue.

In recent years, LNK, an adapter protein, has been found to be associated with metabolic diseases, including hypertension and diabetes. We found that the expression of LNK in human adipose tissue was positively correlated with serum glucose and insulin in obese people. We examined the role of LNK in insulin resistance and systemic energy metabolism using LNK-deficient mice (LNK-/-). With consumption of a high-fat diet, wild type (WT) mice accumulated more intrahepatic triglyceride, higher serum triglyceride (TG), free fatty acid (FFA) and high sensitivity C-reactive protein (hsCRP) compared with LNK-/- mice. However, there was no significant difference between LNK-/- and WT mice under normal chow diet. Meanwhile, glucose transporter 4 (GLUT4) expression in adipose tissue and insulin-stimulated glucose uptake in adipocytes were increased in LNK-/- mice. LNK-/- adipose tissue showed activated reactivity for IRS1/PI3K/Akt/AS160 signaling, and administration of a PI3K inhibitor impaired glucose uptake. In conclusion, LNK plays a pivotal role in adipose glucose transport by regulating insulin-mediated IRS1/PI3K/Akt/AS160 signaling.

AMPK-dependent regulation of GLP1 expression in L-like cells.

This study examined whether AMPK, an evolutionarily conserved sensor of cellular energy status, determines the production of glucagon-like peptide-1 (GLP1). A negative relation existed between phosphorylation of AMPKα and the expression and secretion of GLP1 during changes in energy status in STC-1 cells, an L-like cell line. High concentration of glucose (25 mmol/L) decreased AMPKα phosphorylation, whereas it stimulated the expression and secretion of GLP1 relative to 5.6 mmol/L glucose. Serum starvation upregulated AMPKα phosphorylation, whereas it reduced GLP1 production significantly. Stimulation of AMPK phosphorylation by AICAR and overexpression of wild-type AMPKα1, constitutively active AMPKα1 plasmids, or AMPKα1 lentivirus particles suppressed proglucagon mRNA and protein contents in STC-1 cells. Inactivation of AMPK by Compound C, AMPKα1 siRNA or kinase-inactive AMPKα1 mutant increased the expression and secretion of GLP1. Our results suggest that AMPKα1 may link energy supply with the production of GLP1 in L-like cells.

Ghrelin regulates GLP-1 production through mTOR signaling in L cells.

Glucagon-like peptide (GLP-1), an intestinal incretin produced in L-cells and released in response to meal intake, functions to promote insulin secretion and to decrease plasma glucose. Ghrelin is an orexigenic hormone critical for glucose homeostasis. The molecular mechanism by which ghrelin alters GLP-1 production remains largely unknown. Here we showed that ghrelin attenuates GLP-1 production through mTOR signaling. In GHSR1a null mice, ileal mTOR signaling, proglucagon and circulating GLP-1 were significantly increased. Antagonism of the GHSR1a by D-Lys-3-GHRP-6 increased GLP-1 synthesis and release in STC-1 cells. Treatment of STC-1 cells with ghrelin decreased the production of GLP-1. This effect was associated with a significant inhibition of mTOR signaling. Overexpression of ghrelin inhibited proglucagon promoter activity and GLP-1 production. Inhibition of mTOR activity by mTOR siRNA blocked D-Lys-3-GHRP-6 induced GLP-1 production in STC-1 cells. Our results suggest that mTOR signaling mediates the inhibitory effect of ghrelin on GLP-1 production.