Mucin1 induced trophoblast dysfunction in gestational diabetes mellitus via Wnt/ß-catenin pathway.

BACKGROUND: To elucidate the role of Mucin1 (MUC1) in the trophoblast function (glucose uptake and apoptosis) of gestational diabetes mellitus (GDM) women through the Wnt/ß-catenin pathway. METHODS: Glucose uptake was analyzed by plasma GLUT1 and GLUT4 levels with ELISA and measured by the expression of GLUT4 and INSR with immunofluorescence and Western blotting. Apoptosis was measured by the expression of Bcl-2 and Caspase3 by Western blotting and flow cytometry. Wnt/ß-catenin signaling measured by Western blotting. In vitro studies were performed using HTR-8/SVneo cells that were cultured and treated with high glucose (HG), sh-MUC1 and FH535 (inhibitor of Wnt/ß-catenin signaling). RESULTS: MUC1 was highly expressed in the placental trophoblasts of GDM, and the Wnt/ß-catenin pathway was activated, along with dysfunction of glucose uptake and apoptosis. MUC1 knockdown resulted in increased invasiveness and decreased apoptosis in trophoblast cells. The initial linkage between MUC1, the Wnt/ß-catenin pathway, and glucose uptake was confirmed by using an HG-exposed HTR-8/SVneo cell model with MUC1 knockdown. MUC1 knockdown inhibited the Wnt/ß-catenin signaling pathway and reversed glucose uptake dysfunction and apoptosis in HG-induced HTR-8/SVneo cells. Meanwhile, inhibition of Wnt/ß-catenin signaling could also reverse the dysfunction of glucose uptake and apoptosis. CONCLUSIONS: In summary, the increased level of MUC1 in GDM could abnormally activate the Wnt/ß-catenin signaling pathway, leading to trophoblast dysfunction, which may impair glucose uptake and induce apoptosis in placental tissues of GDM women.

Prognostic assessment of tumor markers in lung carcinomas

SUMMARY BACKGROUND: Serum tumor markers are molecules that are secreted by tumor cells and may be present in small amounts in the serum of healthy individuals. Their role as prognostic factors in lung cancer remains controversial. OBJECTIVE: To assess the prognostic role of CEA, CA 19-9, CA 15-3, and CA 125 in non-squamous non-small cell lung cancer. PATIENTS AND METHODS: A total of 112 patients with non-squamous non-small cell lung cancer from two Oncology Centers were retrospectively analyzed. Tumor marker levels were measured prior to treatment. Data regarding clinical characteristics and overall survival were collected. RESULTS: Median overall survival of all patients was 15.97 months. Pre-treatment elevations of CA 125 and CA 15-3 were associated with shorter overall survival (p=0.004 and p=0.014, respectively). Single CEA and CA 19-9 elevations were not associated with a worse prognosis. Patients with two or more elevated markers had a statistically significant decrease in overall survival (p=0.008). In the multivariate analysis, smoking status and number of positive tumor markers at diagnosis were independently associated with a worse prognosis. CONCLUSION: High pre-treatment levels of tumor markers were correlated with decreased survival in patients with non-squamous non-small cell lung cancer.

Type I Interferon Dependent hsa-miR-145-5p Downregulation Modulates MUC1 and TLR4 Overexpression in Salivary Glands From Sjögren's Syndrome Patients.

Sjögren's syndrome (SS) is an autoimmune disease that mainly affects salivary glands (SG) and is characterized by overactivation of the type I interferon (IFN) pathway. Type I IFNs can decrease the levels of hsa-miR-145-5p, a miRNA with anti-inflammatory roles that is downregulated in SG from SS-patients. Two relevant targets of hsa-miR-145-5p, mucin 1 (MUC1) and toll-like receptor 4 (TLR4) are overexpressed in SS-patients and contribute to SG inflammation and dysfunction. This study aimed to evaluate if hsa-miR-145-5p modulates MUC1 and TLR4 overexpression in SG from SS-patients in a type I IFN dependent manner. Labial SG (LSG) biopsies from 9 SS-patients and 6 controls were analyzed. We determined hsa-miR-145-5p levels by TaqMan assays and the mRNA levels of MUC1, TLR4, IFN-α, IFN-ß, and IFN-stimulated genes (MX1, IFIT1, IFI44, and IFI44L) by real time-PCR. We also performed in vitro assays using type I IFNs and chemically synthesized hsa-miR-145-5p mimics and inhibitors. We validated the decreased hsa-miR-145-5p levels in LSG from SS-patients, which inversely correlated with the type I IFN score, mRNA levels of IFN-ß, MUC1, TLR4, and clinical parameters of SS-patients (Ro/La autoantibodies and focus score). IFN-α or IFN-ß stimulation downregulated hsa-miR-145-5p and increased MUC1 and TLR4 mRNA levels. Hsa-miR-145-5p overexpression decreased MUC1 and TLR4 mRNA levels, while transfection with a hsa-miR-145-5p inhibitor increased mRNA levels. Our findings show that type I IFNs decrease hsa-miR-145-5p expression leading to upregulation of MUC1 and TLR4. Together, this suggests that type I interferon-dependent hsa-miR-145-5p downregulation contributes to the perpetuation of inflammation in LSG from SS-patients.

Annexin A1/Formyl Peptide Receptor Pathway Controls Uterine Receptivity to the Blastocyst.

Embryo implantation into the uterine wall is a highly modulated, complex process. We previously demonstrated that Annexin A1 (AnxA1), which is a protein secreted by epithelial and inflammatory cells in the uterine microenvironment, controls embryo implantation in vivo. Here, we decipher the effects of recombinant AnxA1 in this phenomenon by using human trophoblast cell (BeWo) spheroids and uterine epithelial cells (Ishikawa; IK). AnxA1-treated IK cells demonstrated greater levels of spheroid adherence and upregulation of the tight junction molecules claudin-1 and zona occludens-1, as well as the glycoprotein mucin-1 (Muc-1). The latter effect of AnxA1 was not mediated through IL-6 secreted from IK cells, a known inducer of Muc-1 expression. Rather, these effects of AnxA1 involved activation of the formyl peptide receptors FPR1 and FPR2, as pharmacological blockade of FPR1 or FPR1/FPR2 abrogated such responses. The downstream actions of AnxA1 were mediated through the ERK1/2 phosphorylation pathway and F-actin polymerization in IK cells, as blockade of ERK1/2 phosphorylation reversed AnxA1-induced Muc-1 and claudin-1 expression. Moreover, FPR2 activation by AnxA1 induced vascular endothelial growth factor (VEGF) secretion by IK cells, and the supernatant of AnxA1-treated IK cells evoked angiogenesis in vitro. In conclusion, these data highlight the role of the AnxA1/FPR1/FPR2 pathway in uterine epithelial control of blastocyst implantation.

High-resolution structure of intramolecularly proteolyzed human mucin-1 SEA domain.

SEA domains are ubiquitous in large proteins associated with highly glycosylated environments. Certain SEA domains undergo intramolecular proteolysis involving a nucleophilic attack of a serine hydroxyl group on the preceding glycine carbonyl. The mucin-1 (MUC1) SEA domain has been extensively investigated as a model of intramolecular proteolysis. Since neither a general base, a general acid, nor an oxyanion hole could be identified in MUC1 SEA, it has been suggested that proteolysis is accelerated by a non-planarity of the scissile peptide bond imposed by protein folding. A reactant distorted peptide bond has been also invoked to explain the autoproteolysis of several unrelated proteins. However, the only evidence of peptide distortion in MUC1 SEA stems from molecular dynamic simulations of the reactant modeled upon a single NMR structure of the cleaved product. We report the first high-resolution X-ray structure of cleaved MUC1 SEA. Structural comparison with uncleaved SEA domains suggests that the number of residues evolutionarily inserted in the cleaved loop of MUC1 SEA precludes the formation of a properly hydrogen-bonded beta turn. By sequence analysis, we show that this conformational frustration is shared by all known cleaved SEA domains. In addition, alternative conformations of the uncleaved precursor could be modeled in which the scissile peptide bond is planar. The implications of these structures for autoproteolysis are discussed in the light of the previous research on autoproteolysis.