ALBERT

Description: It is possible that fluorous compounds could be utilized as directing forces in crystal engineering for applications in materials chemistry or catalysis. Although numerous fluorous compounds have been used for various applications, their structures in the solid state remains a lively matter for debate. The reaction of 4-[(2,2,2-trifluoroethoxy)methyl]pyridine with HX(X= I or Cl) yielded new fluorous ponytailed pyridinium halide salts, namely 4-[(2,2,2-trifluoroethoxy)methyl]pyridinium iodide, C8H9F3NO+·I−, (1), and 4-[(2,2,2-trifluoroethoxy)methyl]pyridinium chloride, C8H9F3NO+·Cl−, (2), which were characterized by IR spectroscopy, multinuclei (1H,13C and19F) NMR spectroscopy and single-crystal X-ray diffraction. Structure analysis showed that there are two types of hydrogen bonds, namely N—H...Xand C—H...X. The iodide anion in salt (1) is hydrogen bonded to three 4-[(2,2,2-trifluoroethoxy)methyl]pyridinium cations in the crystal packing, while the chloride ion in salt (2) is involved in six hydrogen bonds to five 4-[(2,2,2-trifluoroethoxy)methyl]pyridinium cations, which is attributed to the smaller size and reduced polarizability of the chloride ion compared to the iodide ion. In the IR spectra, the pyridinium N—H stretching band for salt (1) exhibited a blue shift compared with that of salt (2).

Description: 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 〈 0.05). In RNAseq analysis, MCL1 was identified and increased by the IFNγ-STAT3 axis (p 〈 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 〈 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.