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71.
Haitao Wang Shanji Nan Ying Wang Chengbi Xu 《Journal of cellular and molecular medicine》2021,25(10):4596-4607
(NK) cells are at the first line of defence against tumours, but their anti-tumour mechanisms are not fully understood. We aimed to investigate the mechanism by which NK cells can mediate immunotherapy against head and neck squamous cell carcinoma (HNSCC). We collected fifty-two pairs of HNSCC tissues and corresponding adjacent normal tissues; analysis by RT-qPCR showed underexpression of CXCL14 in HNSCC tissues. Primary NK cells were then isolated from the peripheral blood of HNSCC patients and healthy donors. CXCL14 was found to be consistently under-expressed in the primary NK cells from the HNSCC patients. However, CXCL14 expression was increased in IL2-activated primary NK cells and NK-92 cells. We next evaluated NK cell migration, IFN-γ and TNF-α expression, cytotoxicity and infiltration in response to CXCL14 overexpression or knockdown using gain- and loss-of-function approach. The results exhibited that CXCL14 overexpression promoted NK cell migration, cytotoxicity and infiltration. Subsequent in vivo experiments revealed that CXCL14 suppressed the growth of HNSCC cells via activation of NK cells. ChIP was applied to study the enrichment of H3K27ac, p300, H3K4me1 and CDX2 in the enhancer region of CXCL14, which showed that CDX2/p300 activated the enhancer of CXCL14 to up-regulate its expression. Rescue experiments demonstrated that CDX2 stimulated NK cell migration, cytotoxicity and infiltration through up-regulating CXCL14. In vivo data further revealed that CDX2 suppressed tumorigenicity of HNSCC cells through enhancement of CXCL14. To conclude, CDX2 promotes CXCL14 expression by activating its enhancer, which promotes NK cell–mediated immunotherapy against HNSCC. 相似文献
72.
Zhuyun Qin Shixuan Shen Kaiyong Qu Yu Nie Haitao Zhang 《Journal of cellular and molecular medicine》2021,25(13):6448-6454
Myocardial ischemia-reperfusion injury (MIRI) with concurrent severe sepsis has led to substantial mortality. Mild hypothermia (MHT) has been proved to have a therapeutic effect in either MIRI or severe sepsis, which suggests it might be beneficial for MIRI complicating severe sepsis. In this study, Sprague-Dawley rats with MIRI complicating severe sepsis were allotted in either MHT (33 ± 0.5°C) group or normothermia (NT, 37 ± 0.5°C) group; as control, rats receiving sham surgery and normal saline were kept at NT. After 2h of temperature maintenance, blood and heart tissue were acquired for detections. Lactate dehydrogenase (LDH) and MB isoenzyme of creatine kinase (CK-MB) in blood, triphenyl tetrazolium chloride and Evans blue staining, hematoxylin and eosin staining for myocardium were employed to detect myocardial damage. Tumor necrosis factor (TNF)-α and caspase-3 was performed by immunohistochemistry to exam myocardial inflammation and apoptosis. Detection of NADPH oxidase (NOX) 2 was for myocardial oxidative stress. In MHT group, systolic blood pressure was improved significantly compared with NT group. Myocardial infarct size, morphological change, LDH and CK-MB levels were attenuated compared to NT group. Moreover, less expressions of TNF-α, caspase-3 and NOX2 in MHT group were presented compared with NT group. MHT showed cardioprotection by improving cardiac dysfunction, reducing myocardial infarct size and attenuating myocardial injury, inflammation, apoptosis and oxidative stress. 相似文献
73.
Shu-Hua Zhang Jiewei Yang Hao Ma Yu Yang Guo-Feng Zhou Xue Zhao Rui Xu Dan Nie Guo-Gang Zhang Jun-Jie Shan Cheng-Bin Cui Chang-Wei Li 《化学与生物多样性》2021,18(5):e2100128
Five new peptaibols, longibramides A–E ( 1 – 5 ) with 11 amino acid residues, were isolated from a fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was isolated from a mushroom Clitocybe nebularis (Batsch) P. Kumm collected from coniferous forest in the subboreal area of northeast China. The structures of longibramides A–E were determined by their spectroscopic data (NMR and MS-MS spectra), their absolute configurations were determined by X-ray diffractions and Marfey's analyses. The X-ray diffractions of longibramides A, B, and the similar CD spectra of A–E showed that they all had α-helix conformations. Longibramides B and E showed moderate cytotoxicities against BV2 and MCF-7 cells and also showed some inhibitory effects against methicillin-resistant Staphylococcus aureus MRSA T144. L-trans-Hyp was not commonly found in natural peptaibols, which was the 6th or 10th amino acid residue in longibramides C–E. The X-ray diffractions of longibramides A and B afforded the accuracy conformations of their secondary structures, which maybe help to interpret the structure-activity relationships of the family of peptaibols in the future. 相似文献
74.
Nie Hongtao Zheng Mengge Wang Zhengxing Xu Qiaoyue Yin Zhihui Zhang Yanming Yan Xiwu 《Functional & integrative genomics》2021,21(3-4):341-353
Functional & Integrative Genomics - Growth is one of the most important traits of aquaculture breeding programs. Understanding the mechanisms underlying growth differences between individuals... 相似文献
75.
Non-small cell lung cancer (NSCLC) is the main reason of cancer linked mortality and around 80% of cases diagnosed in advanced stage. Therefore current study designed to evaluate the deregulation of miRNA-194 and miRNA-192 in different body fluid of Non small cell lung cancer participants. Present study recruited newly diagnosed histopathologically confirmed. It was observed that the 40% NSCLC participants showed elevated miR-194 expression and 60% NSCLC participants showed reduced miR-194 expression in serum sample while in Bronchial wash, only 20% NSCLC participants showed elevated miR-194 expression while 80% showed reduced miR-194 expression (p = 0.003). It was found that the 54% NSCLC participants showed elevated miR-192 expression and 55% NSCLC participants showed reduced miR-192 expression in serum sample while In Bronchial wash sample, only 25% NSCLC participants showed high miR-192 expression while 75% showed low miR-192 expression (P = 0.0004). Expression of miR-194 was significantly associated with TNM stages (p < 0.0001, p < 0.0001), distant organ metastases (p < 0.0001, p < 0.0001), pathological grade (p = 0.0009, p = 0.0005) among serum sample and bronchial wash sample. Same observation was found with expression of miR-192 and it was significantly associated with TNM stages (p < 0.0001, p < 0.0001), distant organ metastases (p < 0.0001, p < 0.0001), pathological grade (p = 0.006, p = 0.001) among serum sample and bronchial wash sample. It was observed that the NSCLC participants who had high serum based miR-194 expression showed 22 months of overall median survival while low expression of serum based miR-194 expression showed 18 months of overall median survival. Present study suggests that decreased expression of miR-194 and miR-192 was significantly associated with different clinical features of NSCLC cases. However, significantly higher number of NSCLC cases showed low expression of miR-194 and miR-192 in bronchial lavage sample. Decreased poor overall survival was found to be associated with bronchial wash sample with respect to low miR-194 and miR-192 expression while NSCLC participants showed better overall survival with high miR-194 and miR-192 expression. This suggested decreased expression of miR-192 and miR-194 expression could be the potential prognostic marker among NSCLC participants. 相似文献
76.
Cancer cell spheroids have been shown to be more physiologically relevant to native tumor tissue than monolayer 2D culture cells. Due to enhanced intercellular communications among cells in spheroids, spheroid secreted exosomes which account for transcellular transportation should exceed those from 2D cell culture and may display a different expression pattern of miRNA or protein. To test this, we employed a widely used pancreatic cancer cell line, PANC-1, to create 3D spheroids and compared exosomes generated by both 2D cell culture and 3D PANC-1 spheroids. We further measured and compared exosomal miRNA and GPC-1 protein expression with qRT-PCR and enzyme-linked immunosorbent assay, respectively. It showed that PANC-1 cells cultured in 3D spheroids can produce significantly more exosomes than PANC-1 2D cells and exosomal miRNA and GPC-1 expression derived from spheroids show more features relevant to the progression of pancreatic cancer. These findings point to the potential importance of using spheroids as in vitro model to study cancer development and progression. 相似文献
77.
Site fidelity refers to the restriction of dispersal distance of an animal and its tendency to return to a stationary site. To our knowledge, the homing ability of freshwater turtles and their fidelity is reportedly very low in Asia. We examined mark–recapture data spanning a 4‐year period in Diaoluoshan National Nature Reserve, Hainan Province, China, to investigate the site fidelity and homing behavior of big‐headed turtles Platysternon megacephalum. A total of 11 big‐headed turtles were captured, and all individuals were used in this mark–recapture study. The site fidelity results showed that the adult big‐headed turtles (n = 4) had a 71.43% recapture rate in the original site after their release at the same site, whereas the juveniles (n = 1) showed lower recapture rates (0%). Moreover, the homing behavior results showed that the adults (n = 5) had an 83.33% homing rate after displacement. Adult big‐headed turtles were able to return to their initial capture sites (home) from 150 to 2,400 m away and precisely to their home sites from either upstream or downstream of their capture sites or even from other streams. However, none of the juveniles (n = 4) returned home, despite only being displaced 25–150 m away. These results indicated that the adult big‐headed turtles showed high fidelity to their home site and strong homing ability. In contrast, the juvenile turtles may show an opposite trend but further research is needed. 相似文献
78.
Ji-Hong Hu Jing-Jing Nie Zhen-Xiang Gao Qing-Hua Weng Zhen-He Wang Chuan-Bao Li 《Free radical research》2013,47(9):961-969
AbstractEmerging evidence suggests that microbial pathogens may induce oxidative stress in infected hosts. The aim of the present study was to investigate the relationship between changes in oxidative stress and intestinal infection with and without antibiotic treatment in animal models. Sprague-Dawley (SD) rats were divided into three groups: rats infected with Salmonella enterica serovar Enteritidis (S. enteritidis), rats infected with S. enteritidis followed by norfloxacin treatment, and the control group. To evaluate oxidative stress changes, levels of 8-oxo-7,8-dihydroguanosine (8-oxo-Gsn) and 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxo-dGsn), which represented oxidative damage to RNA and DNA, respectively, were analysed in urine and tissue samples. In urine, the level of 8-oxo-Gsn increased significantly after oral exposure to S. enteritidis (p?≤?0.001) and returned to baseline after recovery. Notably, norfloxacin treatment decreased the level of 8-oxo-Gsn in urine significantly (p?=?0.001). Changes of 8-oxo-Gsn measured in tissues from the small intestine, colon, liver and spleen were consistent with 8-oxo-Gsn measured in urine. Our study suggested that 8-oxo-Gsn in urine may serve as a highly sensitive biomarker for evaluating the severity of S. enteritidis infection and the effectiveness of antibiotic treatment against infection. 相似文献
79.
Thirteen species of Pyrrhalta Joannis, 1865 with black elytron are reviewed. A key to species, photographs of aedeagus and habitus are provided. Pyrrhalta qianana
sp. n. is described from Guizhou, China. Pyrrhalta martensi Medvedev & Sprecher-Uebersax, 1999 is newly recorded from China (Tibet). 相似文献
80.
Lei Li Den-bang Chen Chao Lin Kang Cao Yang Wan Xin-yu Zhao Chun-lai Nie Zhu Yuan Yu-quan Wei 《Apoptosis : an international journal on programmed cell death》2013,18(4):467-479
PNAS-4, a novel pro-apoptotic gene, was activated during the early response to DNA damage. Previous studies have shown that hPNAS-4 can inhibit tumor growth when over-expressed in ovarian cancer cells. However, the underlying action mechanism remains elusive. In this work, we found that hPNAS-4 expression was significantly increased in SKOV3 cells when exposed to cisplatin, methyl methanesulfonate or mitomycin C, and that its overexpression could induce proliferation inhibition, S phase arrest and apoptosis in A2780s and SKOV3 ovarian cancer cells. The S phase arrest caused by hPNAS-4 was associated with up-regulation of p21. p21 is p53-dispensable and correlates with activation of ERK, and activation of the Cdc25A-Cdk2-Cyclin E/Cyclin A pathway, while the pro-apoptotic effects of hPNAS-4 were mediated by activation of caspase-9 and -3 other than caspase-8, and accompanied by release of AIF, Smac and cytochrome c into the cytosol. Taken together, these data suggest a new mechanism by which hPNAS-4 inhibits proliferation of ovarian cancer cells by inducing S phase arrest and apoptosis via activation of Cdc25A-Cdk2-Cyclin E/Cyclin A axis and mitochondrial dysfunction-mediated caspase-dependent and -independent apoptotic pathways. To our knowledge, we provide the first molecular evidence for the potential application of hPNAS-4 as a novel target in ovarian cancer gene therapy. 相似文献