Natural Coevolution of Tumor and Immunoenvironment in Glioblastoma.

Isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM) has a dismal prognosis. A better understanding of tumor evolution holds the key to developing more effective treatment. Here we study GBM\u27s natural evolutionary trajectory by using rare multifocal samples. We sequenced 61,062 single cells from eight multifocal IDH wild-type primary GBMs and defined a natural evolution signature (NES) of the tumor. We show that the NES significantly associates with the activation of transcription factors that regulate brain development, including MYBL2 and FOSL2. Hypoxia is involved in inducing NES transition potentially via activation of the HIF1A-FOSL2 axis. High-NES tumor cells could recruit and polarize bone marrow-derived macrophages through activation of the FOSL2-ANXA1-FPR1/3 axis. These polarized macrophages can efficiently suppress T-cell activity and accelerate NES transition in tumor cells. Moreover, the polarized macrophages could upregulate CCL2 to induce tumor cell migration. SIGNIFICANCE: GBM progression could be induced by hypoxia via the HIF1A-FOSL2 axis. Tumor-derived ANXA1 is associated with recruitment and polarization of bone marrow-derived macrophages to suppress the immunoenvironment. The polarized macrophages promote tumor cell NES transition and migration. This article is highlighted in the In This Issue feature, p. 2711

A macrophage-pericyte axis directs tissue restoration via amphiregulin-induced transforming growth factor beta activation

The epidermal growth factor receptor ligand Amphiregulin has a well-documented role in the restoration of tissue homeostasis after injury; however, the mechanism by which Amphiregulin contributes to wound repair remains unknown. Here we show that Amphiregulin functioned by releasing bioactive transforming growth factor beta (TGF-β) from latent complexes via integrin-αV activation. Using acute injury models in two different tissues, we found that by inducing TGF-β activation on mesenchymal stromal cells (pericytes), Amphiregulin induced their differentiation into myofibroblasts, thereby selectively contributing to the restoration of vascular barrier function within injured tissue. Furthermore, we identified macrophages as a critical source of Amphiregulin, revealing a direct effector mechanism by which these cells contribute to tissue restoration after acute injury. Combined, these observations expose a so far under-appreciated mechanism of how cells of the immune system selectively control the differentiation of tissue progenitor cells during tissue repair and inflammation

The Importance of and a Method for Including Transfection Efficiency Into Real-Time PCR Data Analyses

ABSTRACT: The polymerase chain reaction (PCR) is widely used to ascertain absolute or relative changes in the expression levels of specific genes as a function of cell type or in response to changes in environmental stimuli. Real-time PCR is an advance which allows for the analysis of gene expression over a wide range of initial cDNA concentrations, where the cDNA is the product of reverse transcriptase reactions applied to RNA samples. With the advent and advances in gene delivery technologies, it is now common for the cellular responses under scrutiny to be initiated via the expression of an exogenously delivered gene. When transfection (or transduction) is a part of the procedure used to prepare cell samples for real-time PCR, it is necessary to take the efficiency of gene delivery into account. Here a robust mathematical model for such analyses is derived, and validated with theoretical and experimental support. Comparison to existing analysis methods is presented to demonstrate the high significance of noting transfection, loading, and primer PCR efficiencies when processing PCR data

Microscopic study on the carrier distribution in optoelectronic device structures: Experiment and modeling

Scanning capacitance microscopy(SCM) and scanning spreading resistance microscopy(SSRM) both are capable of mapping the2-demensional carrier distribution in semiconductor device structures, which is essential in determining their electrical and optoelectronic performances. In this work, cross-sectional SCM1,2 is used to study the InGaAs/InP P-i-N junctions prepared by area-selective p-type diffusion. The diffusion lengths in the depth as well as the lateral directions are obtained for junctions under different window sizes in mask, which imply that narrow windows may result in shallow p-n junctions. The analysis is beneficial to design and fabricate focal plane array of near infrared photodetectors with high duty-cycle and quantum efficiency. On the other hand, SSRM provides unparalleled spatial resolution(<10 nm) in electrical characterization3 that is demanded for studying low-dimensional structures. However, to derive the carrier density from the measured local conductance in individual quantum structures, reliable model for SSRM is necessary but still not well established. Based on the carrier concentration related transport mechanisms, i.e. thermionic emission and thermionic field emission4,5, we developed a numerical model for the tip-sample Schottky contact4. The calculation is confronted with SSRM study on the dose-calibrated quantum wells(QWs).?2011 SPIE-OSA-IEEE