Can hidradenitis suppurativa patients classify their lesions by means of a digital lesion identification scheme?

BACKGROUND AND OBJECTIVES: Hidradenitis suppurativa (HS) differs widely with respect to its clinical presentation. Literature imposes different phenotypes potentially implying different treatment modalities. The aim of this study is to develop a validated scheme that enables HS patients to identify their own lesion types. PATIENTS AND METHODS: The developed schemes for physicians and patients were implemented in a specific software. Upon patient consent, the physician used the software to document the lesions identified. Patients subsequently logged into the patient-version of the software from the convenience of their home and selected the lesions they identified on themselves. Afterwards the correlation between professionals and patients was tested. RESULTS: For seven lesion types, correlation coefficients were statistically significant. A large/strong correlation between patients and physicians was found for the draining fistulas (0.59) and double-ended comedones (0.50). For five other lesion types, correlation was medium/moderate, namely the inflammatory nodule (0.37), abscess (0.30), accordion like-/ bridged scar (0.45), epidermal cyst (0.33) and pilonidal sinus (0.39). CONCLUSIONS: HS-patients demonstrate high willingness to share their experiences and data. Therefore, a self-assessment scheme, as the developed LISAI, can be a valuable tool to enrich patient surveys with the identification of lesion types, for instance as a basis for phenotyping.

Adaptive mechanoproperties mediated by the formin FMN1 characterize glioblastoma fitness for invasion.

Glioblastoma are heterogeneous tumors composed of highly invasive and highly proliferative clones. Heterogeneity in invasiveness could emerge from discrete biophysical properties linked to specific molecular expression. We identified clones of patient-derived glioma propagating cells that were either highly proliferative or highly invasive and compared their cellular architecture, migratory, and biophysical properties. We discovered that invasiveness was linked to cellular fitness. The most invasive cells were stiffer, developed higher mechanical forces on the substrate, and moved stochastically. The mechano-chemical-induced expression of the formin FMN1 conferred invasive strength that was confirmed in patient samples. Moreover, FMN1 expression was also linked to motility in other cancer and normal cell lines, and its ectopic expression increased fitness parameters. Mechanistically, FMN1 acts from the microtubule lattice and promotes a robust mechanical cohesion, leading to highly invasive motility.

The Amot/integrin protein complex transmits mechanical forces required for vascular expansion.

Vascular development is a complex multistep process involving the coordination of cellular functions such as migration, proliferation, and differentiation. How mechanical forces generated by cells and transmission of these physical forces control vascular development is poorly understood. Using an endothelial-specific genetic model in mice, we show that deletion of the scaffold protein Angiomotin (Amot) inhibits migration and expansion of the physiological and pathological vascular network. We further show that Amot is required for tip cell migration and the extension of cellular filopodia. Exploiting in vivo and in vitro molecular approaches, we show that Amot binds Talin and is essential for relaying forces between fibronectin and the cytoskeleton. Finally, we provide evidence that Amot is an important component of the endothelial integrin adhesome and propose that Amot integrates spatial cues from the extracellular matrix to form a functional vascular network.

RhoA knockout fibroblasts lose tumor-inhibitory capacity in vitro and promote tumor growth in vivo.

Fibroblasts are a main player in the tumor-inhibitory microenvironment. Upon tumor initiation and progression, fibroblasts can lose their tumor-inhibitory capacity and promote tumor growth. The molecular mechanisms that underlie this switch have not been defined completely. Previously, we identified four proteins overexpressed in cancer-associated fibroblasts and linked to Rho GTPase signaling. Here, we show that knocking out the Ras homolog family member A (RhoA) gene in normal fibroblasts decreased their tumor-inhibitory capacity, as judged by neighbor suppression in vitro and accompanied by promotion of tumor growth in vivo. This also induced PC3 cancer cell motility and increased colony size in 2D cultures. RhoA knockout in fibroblasts induced vimentin intermediate filament reorganization, accompanied by reduced contractile force and increased stiffness of cells. There was also loss of wide F-actin stress fibers and large focal adhesions. In addition, we observed a significant loss of α-smooth muscle actin, which indicates a difference between RhoA knockout fibroblasts and classic cancer-associated fibroblasts. In 3D collagen matrix, RhoA knockout reduced fibroblast branching and meshwork formation and resulted in more compactly clustered tumor-cell colonies in coculture with PC3 cells, which might boost tumor stem-like properties. Coculturing RhoA knockout fibroblasts and PC3 cells induced expression of proinflammatory genes in both. Inflammatory mediators may induce tumor cell stemness. Network enrichment analysis of transcriptomic changes, however, revealed that the Rho signaling pathway per se was significantly triggered only after coculturing with tumor cells. Taken together, our findings in vivo and in vitro indicate that Rho signaling governs the inhibitory effects by fibroblasts on tumor-cell growth.

HEK293-based production platform for γ-retroviral (self-inactivating) vectors: application for safe and efficient transfer of COL7A1 cDNA.

The clinical application of self-inactivating (SIN) retroviral vectors requires an efficient vector production technology. To enable production of γ-retroviral SIN vectors from stable producer cells, new targetable HEK293-based producer clones were selected, providing amphotropic, GALV, or RD114 pseudotyping. Viral vector expression constructs can reliably be inserted at a predefined genomic locus via Flp-recombinase-mediated cassette exchange. Introduction of a clean-up step, mediated by Cre-recombinase, allows the removal of residual sequences that were required for targeting and selection, but were dispensable for the final producer clones and eliminated homology-driven recombination between the tagging and the therapeutic vector. The system was used to establish GALV and RD114 pseudotyping producer cells (HG- and HR820) for a clinically relevant long terminal repeat-driven therapeutic vector, designed for the transfer of a recombinant TCR that delivered titers in the range of 2×10(7) infectious particles (IP)/ml. Production capacity of the amphotropic producer cell (HA820) was challenged by a therapeutic SIN vector transferring the large COL7A1 cDNA. The final producer clone delivered a titer of 4×10(6) IP/ml and the vector containing supernatant was used directly to functionally restore primary fibroblasts and keratinocytes isolated from recessive dystrophic epidermolysis bullosa patients. Thus, the combinatorial approach (fc-technology) to generate producer cells for therapeutic γ-retroviral (SIN) vectors is feasible, is highly efficient, and allows their safe production and application in clinical trials.