Wogonoside inhibits TNF receptor-associated factor 6 (TRAF6) mediated-tumor microenvironment and prognosis of pancreatic cancer.

BACKGROUND: Pancreatic cancer (PC) is one of the worst prognostic cancers. Here, we probed the anti-cancer activity of wogonoside (Wog), a flavonoid isolated from Scutellaria baicalensis Georgi, on PC, as well as potential molecular mechanism. METHODS: Following Wog stimulation, the viability, proliferation, apoptosis, stem cell-like transition, and mesenchymal transition were detected in PC cells. Bioinformatics analysis was used to identify possible signaling pathways involved in the anti-PC activity of Wog. Tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) was overexpressed and TRAF6 activator IL-1ß was used in PC cells to confirm whether Wog exerted anti-PC activity via modulating TRAF6. In vivo, an experiment was conducted to further confirm our supposition. RESULTS: Wog inhibited PC cell proliferation, promoted cell apoptosis, limited PC cell stem cell-like transition and mesenchymal transition. TNF signaling pathway was activated in PC. Besides, Wog inactivated TRAF6/nuclear factor-kappa B (NF-κB)/p65 pathway in PC cells. TRAF6, vascular cell adhesion molecule-1 (VCAM1), CD44, and matrix metalloproteinase 14 (MMP14) expressions were upregulated in PC tissues and negatively correlated with PC survival and prognosis. Finally, Wog suppressed TRAF6 overexpression-induced PC cell stem cell-like transition and mesenchymal transition in vitro and tumor growth in vivo. CONCLUSIONS: Wog exerted anti-cancer activity on PC and suppressed the TRAF6 mediated-tumor microenvironment of PC, thereby regulating PC's prognosis.

TGF-ß sensu stricto signaling regulates skeletal morphogenesis in the sea urchin embryo.

Cell-cell signaling plays a prominent role in the formation of the embryonic skeleton of sea urchins, but the mechanisms are poorly understood. In the present study, we uncover an essential role for TGF-ß sensu stricto signaling in this process. We show that TgfbrtII, a type II receptor dedicated to signaling through TGF-ß sensu stricto, is expressed selectively in skeletogenic primary mesenchyme cells (PMCs) during skeleton formation. Morpholino (MO) knockdowns and studies with a specific TgfbrtII inhibitor (ITD-1) in both S. purpuratus and Lytechinus variegatus embryos show that this receptor is required for biomineral deposition. We provide pharmacological evidence that Alk4/5/7 is the cognate TGF-ß type I receptor that pairs with TgfbrtII and show by inhibitor treatments of isolated micromeres cultured in vitro that both Alk4/5/7 and TgfbrtII function cell-autonomously in PMCs. Gene expression and gene knockdown studies suggest that TGF-ß sensu stricto may be the ligand that interacts with TgfbrtII and support the view that this TGF-ß superfamily ligand provides an essential, permissive cue for skeletogenesis, although it is unlikely to provide spatial patterning information. Taken together, our findings reveal that this model morphogenetic process involves an even more diverse suite of cell signaling pathways than previously appreciated and show that PMCs integrate a complex set of both generalized and spatially localized cues in assembling the endoskeleton.

Signal-dependent regulation of the sea urchin skeletogenic gene regulatory network.

The endoskeleton of the sea urchin embryo is produced by primary mesenchyme cells (PMCs). Maternal inputs activate a complex gene regulatory network (GRN) in the PMC lineage in a cell-autonomous fashion during early development, initially creating a uniform population of prospective skeleton-forming cells. Previous studies showed that at post-blastula stages of development, several effector genes in the network exhibit non-uniform patterns of expression, suggesting that their regulation becomes subject to local, extrinsic cues. Other studies have identified the VEGF and MAPK pathways as regulators of PMC migration, gene expression, and biomineralization. In this study, we used whole mount in situ hybridization (WMISH) to examine the spatial expression patterns of 39 PMC-specific/enriched mRNAs in Strongylocentrotus purpuratus embryos at the late gastrula, early prism and pluteus stages. We found that all 39 mRNAs (including several regulatory genes) showed non-uniform patterns of expression within the PMC syncytium, revealing a global shift in the regulation of the skeletogenic GRN from a cell-autonomous to a signal-dependent mode. In general, localized regions of elevated gene expression corresponded to sites of rapid biomineral deposition. We used a VEGFR inhibitor (axitinib) and a MEK inhibitor (U0126) to show that VEGF signaling and the MAPK pathway are essential for maintaining high levels of gene expression in PMCs at the tips of rods that extend from the ventral region of the embryo. These inhibitors affected gene expression in the PMCs in similar ways, suggesting that VEGF acts via the MAPK pathway. In contrast, axitinib and U0126 did not affect the localized expression of genes in PMCs at the tips of the body rods, which form on the dorsal side of the embryo. Our results therefore indicate that multiple signaling pathways regulate the skeletogenic GRN during late stages of embryogenesis-VEGF/MAPK signaling on the ventral side and a separate, unidentified pathway on the dorsal side. These two signaling pathways appear to be activated sequentially (ventral followed by dorsal) and many effector genes are subject to regulation by both pathways.