The carcinoembryonic antigen (CEAs) family consists of a large group of evolutionarily and structurally divergent glycoproteins. The transforming growth factor-b (TGF-b) signaling pathway has been implicated in the stimulation of CEA secretion in TGF-b-sensitive colon cells, thereby possibly modulating cell adhesion and differentiation. However, the specific CEAs targeted by TGF-b signaling or underlying mechanism of the expression of CEAs has not yet been clarified. In this study, we investigated the specific CEAs targeted by the TGF-b signaling pathway. In nine human gastric cancer cell lines examined, TGF-bresponsive cell lines showed positive expression of CEAs. Expression patterns of CEA proteins correlated well with the level of CEA (CEACAM5) and CEACAM6 transcripts in these cell lines, but CEACAM1 expression was not observed in all of these cells. To investigate the role of TGF-b signaling in CEA expression, we selected two TGFb unresponsive gastric cancer cell lines; SNU638 cells that contain a mutation in the TGF-b type II receptor and SNU484 cells that express low to undetectable level of the TGF-b pathway intermediate protein, Smad3. Restoration of TGF-b signaling in these cells induced expression of the CEAs and increased activity of both CEA (CEACAM5) and CEACAM6 promoters. CEA expression was observed in the epithelium of the stomach of wild-type mice, but was markedly decreased in Smad3 null mice. These findings suggest that CEA (CEACAM5) and CEACAM6 are major target genes for Smad3-mediated TGF-b signaling.

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Dermal pericapillary fibrin is a hallmark of venous disease and is thought to play a pathogenic role in the development of ulceration. However, the actual spatial configuration of pericapillary fibrin is unknown, and it remains unclear whether it truly represents a barrier that can impair physiological exchanges between the blood and dermis. Using confocal microscopy on tissue specimens taken from the edges of venous ulcers in six patients, we report a detailed analysis of dermal pericapillary fibrin deposits. Sections were evaluated with an antibody to human fibrinogen/fibrin and viewed, vertically and horizontally, with confocal microscopy. The distribution of fibrin deposition was highly variable and patchy, with areas of great intensity next to others of marginal intensity. Vertical cut sections showed the highest concentration of fluorescent material next to the lumen of dermal capillaries. Horizontal sections showed that maximal fluorescence was distributed at random. Our findings indicate that fibrin deposits in venous ulcers are patchy and discontinuous around dermal vessels. As such, these deposits are unlikely to act as a true and stable anatomic barrier as originally proposed. However, pericapillary fibrin may still act as a physiological barrier under conditions of poor blood flow where even marginal or patchy fibrin deposition might have a greater effect on the exchange of oxygen and other nutrients between blood and dermis.

An FDA-approved, prototypic, living, bilayered skin construct (BSC) has been used for non-healing wounds. Using this particular construct as proof of principle, we hypothesized that an in vitro 'priming' step may enhance its repertoire of expression of key mediators and genes. The priming step used here was incubation in Dulbecco's modified Eagle's medium (DMEM) for 24 h at 37°C and 5% CO , with or without construct meshing. Microarray and ingenuity pathway analysis (IPA) showed that >1000 genes were overexpressed by the priming step, including interleukin 6 (IL-6), which plays important roles in wound healing. Genes highly overexpressed by priming were those involved in epidermal proliferation and migration. Quantitative real-time PCR (qRT-PCR), immunostaining and western blots verified the results. An epiboly assay (epidermal migration over dermis) showed that BSC epiboly was inhibited by IL-6 neutralizing antibody. Back wounds of nude mice were treated with primed or control BSCs for 3 days prior to harvesting; primed BSCs showed a significantly (p = 0.006) greater level of epidermal migration vs unprimed. Our study demonstrates that an in vitro priming step induces wound healing-related genes in the BSC, leading to a construct that could prove more effective in stimulating wound healing. Copyright © 2014 John Wiley & Sons, Ltd.