Characterization of TGF-ß signaling in a human organotypic skin model reveals that loss of TGF-ßRII induces invasive tissue growth.

Transforming growth factor-ß (TGF-ß) signaling regulates various aspects of cell growth and differentiation and is often dysregulated in human cancers. We combined genetic engineering of a human organotypic three-dimensional (3D) skin model with global quantitative proteomics and phosphoproteomics to dissect the importance of essential components of the TGF-ß signaling pathway, including the ligands TGF-ß1, TGF-ß2, and TGF-ß3, the receptor TGF-ßRII, and the intracellular effector SMAD4. Consistent with the antiproliferative effects of TGF-ß signaling, the loss of TGF-ß1 or SMAD4 promoted cell cycling and delayed epidermal differentiation. The loss of TGF-ßRII, which abrogates both SMAD4-dependent and SMAD4-independent downstream signaling, more strongly affected cell proliferation and differentiation than did loss of SMAD4, and it induced invasive growth. TGF-ßRII knockout reduced cell-matrix interactions, and the production of matrix proteins increased the production of cancer-associated cell-cell adhesion proteins and proinflammatory mediators and increased mitogen-activated protein kinase (MAPK) signaling. Inhibiting the activation of the ERK and p38 MAPK pathways blocked the development of the invasive phenotype upon the loss of TGF-ßRII. This study provides a framework for exploring TGF-ß signaling pathways in human epithelial tissue homeostasis and transformation using genetic engineering, 3D tissue models, and high-throughput quantitative proteomics and phosphoproteomics.

A human antithrombin isoform dampens inflammatory responses and protects from organ damage during bacterial infection.

Severe infectious diseases are often characterized by an overwhelming and unbalanced systemic immune response to microbial infections. Human antithrombin (hAT) is a crucial coagulation inhibitor with anti-inflammatory activities. Here we identify three hAT-binding proteins (CD13, CD300f and LRP-1) on human monocytes that are involved in blocking the activity of nuclear factor-κB. We found that the modulating effect is primarily restricted to the less abundant ß-isoform (hßAT) of hAT that lacks N-glycosylation at position 135. Individuals with a mutation at this position have increased production of hßAT and analysis of their blood, which was stimulated ex vivo with lipopolysaccharide, showed a decreased inflammatory response. Similar findings were recorded when heterozygotic mice expressing hAT or hßAT were challenged with lipopolysaccharide or infected with Escherichia coli bacteria. Our results finally demonstrate that in a lethal E. coli infection model, survival rates increased when mice were treated with hßAT one hour and five hours after infection. The treatment also resulted in a reduction of the inflammatory response and less severe organ damage.

Rho GTPases and cancer.

Rho GTPases are a family of small GTPases, which play an important role in the regulation of the actin cytoskeleton. Not surprisingly, Rho GTPases are crucial for cell migration and therefore highly important for cancer cell invasion and the formation of metastases. In addition, Rho GTPases are involved in growth and survival of tumor cells, in the interaction of tumor cells with their environment, and they are vital for the cancer supporting functions of the tumor stroma. Recent research has significantly improved our understanding of the regulation of Rho GTPase activity, the specificity of Rho GTPases, and their function in tumor stem cells and tumor stroma. This review summarizes these novel findings and tries to define challenging questions for future research.

The presence of transurethral cystometry catheter and type of stress test affect the measurement of abdominal leak point pressure (ALPP) in women with stress urinary incontinence (SUI).

AIMS: Abdominal leak point pressure (ALPP) measurements in female SUI may show variability because of the variations in measurement protocols. The aim of this study is to investigate the effect of cystometry catheter on ALPP measurement and compare the sensitivity of Valsalva and cough maneuvers in demonstrating urinary leakage in women complaining of SUI. METHODS: In this prospective study, 194 female patients complaining of SUI underwent urodynamic studies using a 8-fr urethral cystometry and 10-fr rectal catheter. At the cystometric capacity, Valsalva and then cough ALPP was measured in semi-supine position. The same procedure was repeated after removing the cystometry catheter. The results were analyzed with Chi-square and student's t-test where appropriate. RESULTS: In the whole study group, more patients lost urine when coughing than with Valsalva (122 vs. 93, P = 0.0013). One hundred thirty-seven (71%) women revealed a positive stress test both with and without catheter where the presence of the catheter was associated with significantly higher cough and Valsalva ALPP. In this subgroup of 137 patients, cough-induced ALPP values were significantly higher than Valsalva ALPP. Another 29 (15%) women leaked only after the removal of the catheter. Urine leakage could not be demonstrated in the rest of 28 patients (14%) with any maneuver even without catheter in the semi-supine position. CONCLUSION: Cough-induced stress test is significantly more sensitive than Valsalva to demonstrate urinary leakage. Cystometry catheter significantly increases cough and Valsalva ALPP whereas stress test can be false negative due obstructive effect of cystometry catheter in a group of patients. Stress test may be negative in the semi-supine position in about 14% of women complaining of SUI.