Interleukin-25 is involved in cutaneous T-cell lymphoma progression by establishing a T helper 2-dominant microenvironment

BACKGROUND

Interleukin (IL)-25 is a member of the IL-17 family, which can promote and augment T-helper (Th) type 2 responses. The expression of IL-25 and its cognate receptor, IL-25 receptor (IL-25R), is upregulated and correlated with disease activity in Th2-associated diseases.

OBJECTIVES

To examine the expression and function of IL-25 in cutaneous T-cell lymphoma (CTCL).

METHODS

Expression and location of IL-25 in lesional skin was investigated with immunohistochemistry. The effect of various cytokines on IL-25 production from normal human epidermal keratinocytes was assessed by quantitative reverse-transcription real-time polymerase chain reaction. Serum IL-25 levels were measured by enzyme-linked immunosorbent assay. The direct effect of IL-25 on tumour cells was also examined using CTCL cell lines and peripheral blood mononuclear cells in patients with Sézary syndrome.

RESULTS

IL-25 expression was increased in epidermal keratinocytes in lesional skin of CTCL. Th2 cytokines, IL-4 and IL-13, and periostin induced IL-25 expression by normal human epidermal keratinocytes. Serum IL-25 levels were increased in patients with advanced CTCL and correlated with serum lactate dehydrogenase levels. MyLa cells expressed IL-25R and its expression was augmented by stimulation with IL-25. IL-25 enhanced IL-13 production from MyLa cells via phosphorylation of signal transducer and activator of transcription 6. Peripheral blood mononuclear cells from one patient with Sézary syndrome expressed IL-25R and showed increase of IL-13 production by IL-25.

CONCLUSIONS

Th2 cytokines highly expressed in CTCL lesional skin induce IL-25 production by epidermal keratinocytes, which may, in turn, lead to formation of a Th2-dominant microenvironment through the direct induction of IL-13 by tumour cells.

Fibroblast growth factor 13 regulates glioma cell invasion and is important for bevacizumab-induced glioma invasion

Glioblastoma has the poorest prognosis, and is characterized by excessive invasion and angiogenesis. To determine the invasive mechanisms, we previously used two glioma cell lines (J3T-1 and J3T-2) with different invasive phenotypes. The J3T-1 showed abundant angiogenesis and tumor cell invasion around neovasculature, while J3T-2 showed diffuse cell infiltration into surrounding healthy parenchyma. Microarray analyses were used to identify invasion-related genes in J3T-2 cells, and the expressed genes and their intracellular and intratumoral distribution patterns were evaluated in J3T-2 cell lines, human glioma cell lines, human glioblastoma stem cells and human glioblastoma specimens. To determine the role of the invasion-related genes, invasive activities were evaluated in vitro and in vivo. Fibroblast growth factor 13 (FGF13) was overexpressed in J3T-2 cells compared to J3T-1 cells, and in human glioma cell lines, human glioblastoma stem cells and human glioblastoma specimens, when compared to that of normal human astrocytes. Immunohistochemical staining and the RNA-seq (sequencing) data from the IVY Glioblastoma Atlas Project showed FGF13 expression in glioma cells in the invasive edges of tumor specimens. Also, the intracellular distribution was mainly in the cytoplasm of tumor cells and colocalized with tubulin. Overexpression of FGF13 stabilized tubulin dynamics in vitro and knockdown of FGF13 decreased glioma invasion both in vitro and in vivo and prolonged overall survival of several xenograft models. FGF13 was negatively regulated by hypoxic condition. Silencing of FGF13 also decreased in vivo bevacizumab-induced glioma invasion. In conclusion, FGF13 regulated glioma cell invasion and bevacizumab-induced glioma invasion, and could be a novel target for glioma treatment.

Quantitative analysis of the effect of pulsatile flow on vascular resistance

'Pulsatile flow' has been reported to reduce vascular resistance. In this study, the effect of pulsatile flow was assessed quantitatively, using perfusion of canine hindlimb. The perfusion circuit consisted of roller-type pulsatile pump (Cobe Inc., Stockert pump) and bubble oxygenator (Shiley Inc., S-070/s). Each flow curve was quantified with the mean flow rate (F) and pulse power index (PPI). PPI is derived by Fourier transformation of the flow curve and represents the degree of 'pulsation'. Vascular resistance was determined during perfusion with varied flow rate and PPI. The regression formula between vascular resistance (VR) and two parameters was obtained as follows:

VR(F,PPI) = 41600x(F-1.37) -0.95+913 - PPIx{(3.99x(F-1.33)-040_0.69}

where VR is measured in mmHg. min-1.kg.ml-1; F represents ml.min-1.kg -1 (range from 2.8 to 17.1); and PPI is dimensionless (range from 2.8 to 215.7).

Using this formula, vascular resistance at a fixed flow rate and wave form can be predicted. When the flow rate is 6.27 ml.min-1.kg-1 and the PPI is 1466, (measured values under perfusion with own beating heart) the vascular resistance perfused by own beating heart is obtained. The results indicate that the pulsation of own beating heart contributes to a reduction in vascular resistance to 80%. It is also shown that the value of PPI which is necessary to reduce the vascular resistance to 80% is more than 1300 under the normal flow rate range.

Theory of Floquet band formation and local pseudospin textures in pump-probe photoemission of graphene

Ultrafast materials science promises optical control of physical properties of solids. Continuous-wave circularly polarized laser driving was predicted to induce a light-matter coupled state with an energy gap and a quantum Hall effect, coined Floquet topological insulator. Whereas the envisioned Floquet topological insulator requires high-frequency pumping to obtain well-separated Floquet bands, a follow-up question regards the creation of Floquet-like states in graphene with realistic low-frequency laser pulses. Here we predict that short optical pulses attainable in experiments can lead to local spectral gaps and novel pseudospin textures in graphene. Pump-probe photoemission spectroscopy can track these states by measuring sizeable energy gaps and Floquet band formation on femtosecond time scales. Analysing band crossings and pseudospin textures near the Dirac points, we identify new states with optically induced nontrivial changes of sublattice mixing that leads to Berry curvature corrections of electrical transport and magnetization.