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Tumor cells express immune checkpoints to exhaust CD8+ T cells. Irradiation damages tumor cells and augments tumor immunotherapy in clinical applications. However, the radiotherapy-mediated molecular mechanism affecting CD8+ T cell activity remains elusive. We aimed to uncover the mechanism of radiotherapy augmenting cytotoxic CD8+ T cells in non-small-cell lung cancer (NSCLC). EGFR-positive NSCLC cell lines were co-cultured with CD8+ T cells from healthy volunteers. Tumor cell viability and apoptosis were consequently measured. IFNγ was identified secreted by CD8+ T cells and PBMCs. Therefore, RNAseq was used to screen the IFNγ-mediated gene expression in A549 cells. The irradiation effect to IFNγ-mediated gene expression was investigated using qPCR and western blots. We found that the co-culture of tumor cells stimulated the increase of granzyme B and IFNγ in CD8+ T, but A549 exhibited resistance against CD8+ T cytotoxicity compared to HCC827. Irradiation inhibited A549 proliferation and enhanced apoptosis, augmenting PBMCs-mediated cytotoxicity against A549. We found that IFNγ simultaneously increased phosphorylation on STAT1 and STAT3 in EGFR-positive lung cancer, resulting in overexpression of PD-L1 (p &lt, 0.05). In RNAseq analysis, MCL1 was identified and increased by the IFNγ-STAT3 axis (p &lt, 0.05). We demonstrated that irradiation specifically inhibited phosphorylation on STAT1 and STAT3 in IFNγ-treated A549, resulting in reductions of PD-L1 and MCL1 (both p &lt, 0.05). Moreover, knockdowns of STAT3 and MCL1 increased the PBMCs-mediated anti-A549 effect. This study demonstrated that A549 expressed MCL1 to resist CD8+ T cell-mediated tumor apoptosis. In addition, we found that irradiation suppressed IFNγ-mediated STAT3 phosphorylation and PD-L1 and MCL1 expression, revealing a potential mechanism of radiotherapy augmenting immune surveillance.

Gut microbiota are reported to be associated with many diseases, including cancers. Several bacterial taxa have been shown to be associated with cancer development or response to treatment. However, longitudinal microbiota alterations during the development of cancers are relatively unexplored. To better understand how microbiota changes, we profiled the gut microbiota composition from prostate cancer-bearing mice and control mice at five different time points. Distinct gut microbiota differences were found between cancer-bearing mice and control mice. Akkermansiaceae was found to be significantly higher in the first three weeks in cancer-bearing mice, which implies its role in the early stage of cancer colonization. We also found that Bifidobacteriaceae and Enterococcaceae were more abundant in the second and last sampling week, respectively. The increments of Akkermansiaceae, Bifidobacteriaceae and Enterococcaceae were previously found to be associated with responses to immunotherapy, which suggests links between these bacteria families and cancers. Additionally, our function analysis showed that the bacterial taxa carrying steroid biosynthesis and butirosin and neomycin biosynthesis were increased, whereas those carrying naphthalene degradation decreased in cancer-bearing mice. Our work identified the bacteria taxa altered during prostate cancer progression and provided a resource of longitudinal microbiota profiles during cancer development in a mouse model.

Electron transfer coupling is a critical factor in determining electron transfer rates. This coupling strength can be sensitive to details in molecular geometries, especially intermolecular configurations. Thus, studying charge transporting behavior with a full first-principle approach demands a large amount of computation resources in quantum chemistry (QC) calculation. To address this issue, we developed a machine learning (ML) approach to evaluate electronic coupling. A prototypical ML model for an ethylene system was built by kernel ridge regression with Coulomb matrix representation. Since the performance of the ML models highly dependent on their building strategies, we systematically investigated the generality of the ML models, the choice of features and target labels. The best ML model trained with 40 000 samples achieved a mean absolute error of 3.5 meV and greater than 98% accuracy in predicting phases. The distance and orientation dependence of electronic coupling was successfully captured. Bypassing QC calculation, the ML model saved 10-10

Using poly(3-hexylthiophene) (P3HT) as a model conjugated polymer and atomistic molecular dynamics simulations with carefully verified force fields, we performed in-depth investigations of solvation shell properties of P3HT chains (15 repeating units per chain) in two representative groups of non-polar (or aprotic) organic solvents (better solvents: ortho-dichlorobenzene, bromobenzene, and chlorobenzene; poorer solvents: chloroform, para-xylene, and toluene). We demonstrated that solvation shell relaxation properties in P3HT solutions dictate the formation of regular π-π associations and, hence, crystallinity through the initial chain association and subsequent chain sliding. In contrast, the mean features of polymer-solvent interactions, including solvation free energy and radial distribution function, present little or no difference for all solvent media investigated. Better-solvent media were revealed to bear relatively large values of the first solvation shell relaxation time (τ1 ≫ 100 ps) as well as larger ratios of relaxation times for the first two solvation shells (τ1/τ2 > 2), and vice versa for poorer-solvent media (τ1 ≪ 100 ps and τ1/τ2 < 2). The linear hexyl side-chain unit was noted to substantially enlarge both quantities while notably reducing the solvation free energy as well. As discussed herein, these findings shed new light on the mechanistic features by which solvent quality impacts the degree of π-π association crucial for modern applications with crystalline conjugated polymers.

Background Tumor cells progress to evade immunological attacks and prohibit activity of CD8+ T cells. Irradiation damages tumor cells and augments tumor immunotherapy in clinical application. However, the detail mechanism remains elusive. We aimed to uncover the mechanism of irradiation augmenting cytotoxic CD8+ T cells to suppress tumor progression in non-small-cell lung cancer (NSCLC). Methods EGFR-positive NSCLC cell lines were co-cultured with isolated PBMCs from healthy volunteers, cell viability and apoptosis were measured. RNAseq was used to screen the IFNγ-mediated gene expression in A549 cells. Irradiation was used to augment PBMCs-mediated anti-tumor effect and the irradiation effect to IFNγ-mediated gene expression was investigated using qPCR and Western blots. Results Co-culture of tumor cells stimulates increase of granzyme B and IFNγ in CD8+ T, but A549 exhibits resistance against CD8+ T cytotoxicity. Irradiation inhibits A549 proliferation and enhances apoptosis, augmenting PBMCs-mediated cytotoxicity against A549. IFNγ simultaneously increased phosphorylation on STAT1 and STAT3 in EGFR-positive lung cancer, resulting in overexpression of PD-L1. In RNAseq analysis, MCL1 was identified and increased by IFNγ-STAT3 axis in A549 cells, we found that irradiation specifically inhibits phosphorylation on STAT1 and STAT3 in IFNr-treated A549, resulting in reductions of PD-L1 and MCL1. Moreover, knockdowns of STAT3 and MCL1 increased PBMCs against irradiated A549 cells. Conclusion This study demonstrated that A549 expressed MCL1 against CD8+ T cell-mediated apoptosis. In addition, we found that irradiation suppressed STAT3 phosphorylation and IFNγ-mediated PD-L1 and MCL1 expression, revealing a potential mechanism of irradiation augmenting immune surveillance.

Two hole-transporting materials (HTMs) based on carbohelicene cores, CH1 and CH2, are developed and used in fabricating efficient and stable perovskite solar cells (PSCs). Owing to the rigid conformation of the helicene core, both compounds possess unique CH-π interactions in the crystalline packing pattern and good phase stability, which are distinct from the π-π intermolecular interactions of conventional planar and spiro-type molecules. PSCs based on CH1 and CH2 as HTMs deliver excellent device efficiencies of 19.36 and 18.71%, respectively, outperforming the control device fabricated with spiro-OMeTAD (18.45%). Furthermore, both PSCs exhibit better ambient stability, with 90% of initial performance retained after aging with a 50-60% relative humidity at 25 °C for 500 h. Due to the low production cost of both compounds, these newly designed carbohelicene-type HTMs have the potential for the future commercialization of PSCs.

Contrasting mesoscale aggregate features of a promising conjugated polymer, poly(2,5-bis(3-tetradecylthiophene-2-yl)thieno[3,2-b]thiophenes) (pBTTT-C14), that result from the use of two slightly different aromatic solvents, i.e., toluene and chlorobenzene, for a range of dilute solutions (0.5–1.2 mg/mL) are systematically explored using depolarized dynamic light scattering (DDLS), dynamic/static light scattering (DLS/SLS), small-angle X-ray scattering (SAXS), and scanning transmission electron/scanning electron/transmission electron microscopy (STEM/SEM/TEM) analysis schemes. The central findings are as follows: (1) DDLS and all EM features reveal that whereas pBTTT-C14 aggregate clusters fostered in toluene (a poorer solvent) are moderately anisotropic (cylindrical; aspect ratio ∼3) in shape, they are nearly isotropic (spherical) in chlorobenzene (a better solvent), with mean sizes in the range of a few hundred nanometers. (2) Combined DDLS/DLS/SLS/SAXS analyses indicate that the aggregate clusters in bo...

BACKGROUND Mutations in the human telomerase reverse transcriptase (TERT) promoter contribute to increased TERT activity. The purpose of the present study was to assess the prevalence of TERT promoter mutations in oral cavity squamous cell carcinoma (SCC). METHODS Total DNA was extracted from 201 oral cavity SCC tumors and adjacent normal tissues. Primers were used to amplify the sequence region containing 2 TERT promoter mutations (C228T and C250T) that were then sequenced using the Sanger method. RESULTS Sequencing revealed that 52.5% (104/201) and 12.9% (26/201) of oral cavity SCC tumor tissues and 6.0% (12/201) and 2.5% (5/201) of adjacent normal tissues contained C228T and C250T mutations, respectively. In addition, the C228T mutation was significantly associated with betel nut chewing. CONCLUSION Our results show that mutations in the TERT promoter occur in patients with oral cavity SCC at a high frequency. This suggests that somatic TERT promoter mutations could play a vital role in the pathogenesis and progression of oral cavity SCC. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1131-1137, 2017.

Epidermal growth factor receptor (EGFR) and activin A are both overexpressed in oral cavity squamous cell carcinoma (OSCC). We evaluated their clinical correlation and activin A-mediated EGFR regulation in this study. Overexpression of both transcripts/proteins indicated a poorer prognosis in OSCC patients. Knockdown of endogenous INHBA repressed the expression of EGFR and inhibited activin A-mediated canonical Smads, noncanonical phosphorylation of AKT (ser473) (p-AKT ser473) and SP1. Inhibition of PI3K signaling via its inhibitor attenuated p-AKT ser473 and in turn reduced SP1 and EGFR expression in the presence of recombinant activin A (rActivin A) in OSCC cells, as revealed via a luciferase assay and western blotting. However, canonical Smad signaling repressed the EGFR promoter, as revealed by a luciferase assay. The transcription factor SP1, its coactivator CBP/p300, and Smad proteins were recruited to the EGFR proximal promoter following rActivin A treatment, as revealed by chromatin immunoprecipitation (ChIP). Smad2/3/4 dramatically outcompeted SP1 binding to the EGFR proximal promoter following mithramycin A treatment. Activin A activates the PI3K and Smad pathways to compete for binding to overlapping SP1 consensus sequences on the EGFR proximal promoter. Nevertheless, canonical p-Smad2 was largely repressed in OSCC tumor tissues, suggesting that the activin A-mediated noncanonical pathway is essential for the carcinogenesis of OSCC.

The ability to correlate fullerene solubility with experimentally or computationally accessible parameters can significantly facilitate nanotechnology nowadays for a wide range of applications, while providing crucial insight into optimum design of future fullerene species. To date, there has been no single relationship that satisfactorily describes the existing data clearly manifesting the effects of solvent species, system temperature, and isomer. Using atomistic molecular dynamics simulations on two standard fullerene species, C60 and PCBM ([6,6]-phenyl-C61-butyric acid methyl ester), in a representative series of organic solvent media (i.e., chloroform, toluene, chlorobenzene, 1,3-dichlorobenzene, and 1,2-dichlorobenzene), we show that a single time constant characterizing the dynamic stability of a tiny (angstrom-sized) solvation shell encompassing the fullerene particle can be utilized to effectively capture the known trends of fullerene solubility as reported in the literature. The underlying physics differs substantially between the two fullerene species, however. Although C60 was previously shown to be dictated by a diffusion-limited aggregation mechanism, the side-chain-substituted PCBM is demonstrated herein to proceed with an analogous reaction-limited aggregation with the "reaction rate" set by the fullerene rotational diffusivity in the medium. The present results suggest that dynamic quantities-in contrast to the more often employed, static ones-may provide an excellent means to characterize the complex (entropic and enthalpic) interplay between fullerene species and the solvent medium, shed light on the factors determining the solvent quality of a nanoparticle solution, and, in particular, offer a practical pathway to foreseeing optimum fullerene design and fullerene-solvent interactions.

For π-conjugated polymers, the notion of spectroscopic units or "chromophores" provides illuminating insights into the experimentally observed absorption/emission spectra and the mechanisms of energy/charge transfer. To date, however, no statistical analysis has revealed a direct correspondence between chromophoric and conformational properties-with the latter being fundamental to polymer semiconductors. Herein, we propose a "persistence length" calculation to re-evaluate chain conformation over a full conjugation length. The mesoscale condensed systems of MEH-PPV and MEH-PPV/C60 hybrid (system size ∼10 × 10 × 10 nm3) are utilized as two prototypical model systems, along with a full range of segmental lengths (2-20-mer) and five lowest singlet excited states to hint at the generality of the features presented. We demonstrate, for the first time, that two properly re-defined conformational factors that characterize chain folding and planarity, respectively, capture excellently the population distribution of chromophores in both systems investigated. In contrast, the conventional strategy of utilizing two adjacent monomer units to characterize (local) chain conformation results in only an inconspicuous correlation between the two, as previously reported. It is further shown that chain folding-and not chain planarity-is more relevant in capturing the associated oscillator strength for the first excited state, where the transient dipole moments are known to align with the chain conformation, although the corresponding excitation energy and exciton size seem relatively unaffected. The observed effects of C60 on the MEH-PPV adsorption spectra also agree with recent experimental trends. Overall, the present findings are expected to aid future multiscale computer simulations and spectroscopy-data interpretations for polymer semiconductors and their hybrid systems.

The notion of (static) solvation shells has recently proved fruitful in revealing key molecular factors that dictate the solubility and aggregation properties of fullerene species in polar or ionic solvent media. Using molecular dynamics schemes with carefully evaluated force fields, we have scrutinized both the static and the dynamic features of the solvation shells of single C60 particle for three nonpolar organic solvents (i.e., chloroform, toluene, and chlorobenzene) and a range of system temperatures (i.e., T = 250-330 K). The central findings have been that, while the static structures of the solvation shell remain, in general, insensitive to the effects of changing solvent type or system temperature, the dynamic behavior of solvent molecules within the shell exhibits prominent dependence on both factors. Detailed analyses led us to propose the notion of dynamically stable solvation shell, effectiveness of which can be characterized by a new physical parameter defined as the ratio of two fundamental time constants representing, respectively, the solvent relaxation (or residence) time within the first solvation shell and the characteristic time required for the fullerene particle to diffuse a distance comparable to the shell thickness. We show that, for the five (two from the literature) different solvent media and the range of system temperatures examined herein, this parameter bears a value around unity and, in particular, correlates intimately with known trends of solubility for C60 solutions. We also provide evidence revealing that, in addition to fullerene-solvent interactions, solvent-solvent interactions play an important role, too, in shaping the dynamic solvation shell, as implied by recent experimental trends.

Atomistic molecular dynamics (AMD) simulations are utilized to simultaneously explore the detailed pair interactions, interfacial microstructure, and nanoscale (phase-separated) morphology of a series of thermally annealed C60-MEH-PPV (monomer and oligomer) (poly(2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene)) hybrids. The present study provides essential details for understanding fundamental particle interactions that regulate the microscopic (structural and morphological) features of a standard polymer-fullerene material, paving the way to the eventual goal of capturing the photovoltaic physics of similar hybrid systems widely viewed as a potential alternative to the conventional (inorganic) semiconducting materials. Specifically, we show that two dominant interfacial pair C60-MEH-PPV-mer configurations—denoted as “face-on” or “side-on” motif—can thus be identified. These two motifs seem to be rather universal, and are shown to be dictated by many-body energetic forces in a condensed phase, as they display clear independence on the effects of system temperature, blending ratio, and chain connectivity. Importantly, the pair configurations (which should embed precise information on separation distance and mutual alignment) so unraveled provide an unambiguous first step toward resolving quantum-mechanic properties relevant to the photovoltaic performance of a hybrid material. Although the simulation length scale is limited for one to unequivocally reveal bulk phase behavior, the results on nanoscale phase morphologies are in accord with recent experimental trends regarding the effects of polymer molecular weight and blending ratio. Future outlooks of utilizing the established molecular system for predicting light adsorption and interfacial charge behavior are remarked.

Summary1. Paper electrophoresis provides a simple reproducible method for the study of serum (plasma) lipoproteins. Characteristic species lipoprotein patterns were demonstrated in normal man, monkey, dog and rabbit. 2. This method combined with chemical determinations of serum (plasma) lipids permits detailed investigations of normal and abnormal lipid metabolic states. 3. Elevation of serum (plasma) lipid fractions induced in these species by various experimental procedures were accompanied by a lowering of α lipoprotein and varying degrees of elevation of the β + O fraction.

Starch electrophoresis was employed for the study of the lipoprotein patterns in inborn errors of lipid metabolism. Idiopathic hyperlipemia was characterized by marked increases of cholesterol and phospholipid in the alpha-2-lipoprotein fraction of the serum whereas idiopathic hypercholesteremia showed an increase of these lipids in the beta-lipoprotein fraction. The cholesterol and phospholipid contents in the alpha-1-lipoprotein fractions were diminished in both metabolic errors.

Histochemical and chemical studies of the acid mucopolysaccharide content of the aorta were made in rabbits fed cholesterol for up to seven months. Colloidal iron staining suggested an increase in acid mucopolysaccharide content of the aortas with mild atheromatous lesions but not when severe lesions were present. Chemical determination, however, revealed no increase in the concentration of acid mucopolysaccharide in early lesions, but did reveal a significant increase in the more severely atheromatous aortas of rabbits fed cholesterol for 6 months or more.

SummaryCortisone administration to dogs is followed by a selective rise in plasma alpha-2 globulin and fall in beta globulin which is independent of any associated lipid changes; this shift in globulin distribution has not been observed in humans or rabbits receiving cortisone.

Cortisone has a retarding effect on atherogenesis in cholesterol-fed rabbits, despite higher plasma cholesterol levels. This effect of cortisone is prevented by administration of hyaluronidase. The latter intensifies atherosclerosis and deposition of cholesterol in the liver.

A FAULT of lipid metabolism has been implicated in the genesis of atherosclerosis in man and in experimental animals. Since the production of atherosclerotic lesions in rabbits with hypercholesteremia induced by cholesterol feeding, 1 this substance has been considered of prime significance in atherogenesis. More recently, variations in the ratios of lipid fractions such as the cholesterol: phospholipid and the alpha: beta lipoprotein ratios have been advanced as possible determining factors. 2 At the present time, study of the physical and physicochemical state of serum lipids is receiving considerable emphasis. In several reports Gofman and his co-workers 3 have related certain lipoproteins of specific densities, as differentiated in the ultracentrifuge, to the atherosclerotic process. In addition, a difference has also been reported in the clearing effect of heparin on the blood serum of men with atherosclerosis as compared with normal subjects. 4 Other workers impute a relationship between large fat particles (chylomicrons) and atherogenesis. 5