PI 3-Kinase and the Histone Methyl-Transferase KMT2D Collaborate to Induce Arp2/3-Dependent Migration of Mammary Epithelial Cells.

Breast cancer develops upon sequential acquisition of driver mutations in mammary epithelial cells; however, how these mutations collaborate to transform normal cells remains unclear in most cases. We aimed to reconstitute this process in a particular case. To this end, we combined the activated form of the PI 3-kinase harboring the H1047R mutation with the inactivation of the histone lysine methyl-transferase KMT2D in the non-tumorigenic human mammary epithelial cell line MCF10A. We found that PI 3-kinase activation promoted cell-cycle progression, especially when growth signals were limiting, as well as cell migration, both in a collective monolayer and as single cells. Furthermore, we showed that KMT2D inactivation had relatively little influence on these processes, except for single-cell migration, which KMT2D inactivation promoted in synergy with PI 3-kinase activation. The combination of these two genetic alterations induced expression of the ARPC5L gene that encodes a subunit of the Arp2/3 complex. ARPC5L depletion fully abolished the enhanced migration persistence exhibited by double-mutant cells. Our reconstitution approach in MCF10A has thus revealed both the cell function and the single-cell migration, and the underlying Arp2/3-dependent mechanism, which are synergistically regulated when KMT2D inactivation is combined with the activation of the PI 3-kinase.

Mouth opening in systemic sclerosis: A longitudinal analysis from the French National Cohort Study.

BACKGROUND: Few studies have evaluated mouth opening (MO) in systemic sclerosis (SSc). None have studied MO trajectories. OBJECTIVE: To study MO trajectories in SSc. METHODS: This multicentre study included patients enrolled in the French national SSc cohort with at least one MO assessment, described patients based on MO baseline measure, modeled MO trajectories, and associated MO measures with SSc prognosis. RESULTS: We included 1101 patients. Baseline MO was associated with disease severity. On Kaplan-Meier analysis, MO < 30 mm was associated with worse 30-year-survival (p<0.01) and risk of pulmonary arterial hypertension (p<0.05). Individual MO trajectories were heterogenous among patients. The best model of MO trajectories according to latent-process mixed modeling showed that 88.8% patients had a stable MO trajectory and clustered patients into 3 groups that predicted SSc survival (p<0.05) and interstitial lung disease (ILD) occurrence (p<0.05). The model highlighted a cluster of 9.5% patients with diffuse cutaneous SSc (dcSSc) (p<0.05) and high but decreasing MO over 1 year (p<0.0001) who were at increased risk of poor survival and ILD. CONCLUSION: MO, which is a simple and reliable measure, could be used to predict disease severity and survival in SSc. Although MO remained stable in most SSc patients, dcSSc patients with high but decreasing MO were at risk of poor survival and ILD. This article is protected by copyright. All rights reserved.

Focal field analysis of highly multi-mode fiber beams based on modal decomposition.

In this work, a numerical modal decomposition approach is applied to model the optical field of laser light after propagating through a highly multi-mode fiber. The algorithm for the decomposition is based on the reconstruction of measured intensity profiles along the laser beam caustic with consideration of intermodal degrees of coherence derived from spectral analysis. To enhance the accuracy of the model, different approaches and strategies are applied and discussed. The presented decomposition into a set of linearly polarized modes enables both the wave-optical simulation of radiation transport by highly multi-mode fibers and, additionally, the analysis of free-space propagation with arbitrarily modified complex amplitude distributions.