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The acquisition of chemoresistance remains a major cause of cancer mortality due to the limited accessibility of targeted or immune therapies. However, given that severe alterations of molecular features during epithelial‐to‐mesenchymal transition (EMT) lead to acquired chemoresistance, emerging studies have focused on identifying targetable drivers associated with acquired chemoresistance. Particularly, AXL, a key receptor tyrosine kinase that confers resistance against targets and chemotherapeutics, is highly expressed in mesenchymal cancer cells. However, the underlying mechanism of AXL induction in mesenchymal cancer cells is poorly understood. Our study revealed that the YAP signature, which was highly enriched in mesenchymal‐type lung cancer, was closely correlated to AXL expression in 181 lung cancer cell lines. Moreover, using isogenic lung cancer cell pairs, we also found that doxorubicin treatment induced YAP nuclear translocation in mesenchymal‐type lung cancer cells to induce AXL expression. Additionally, the concurrent activation of TGFβ signaling coordinated YAP‐dependent AXL expression through SMAD4. These data suggest that crosstalk between YAP and the TGFβ/SMAD axis upon treatment with chemotherapeutics might be a promising target to improve chemosensitivity in mesenchymal‐type lung cancer.

Abbreviations

AUC
area under the curve
AXL
AXL receptor tyrosine kinase
BCL2
B‐cell lymphoma 2
CTD2
cancer target discovery and development
CTGF
connective tissue growth factor
DEG
differentially expressed genes
DOXO
doxorubicin
EMT
epithelial–mesenchymal transition
Eto
etoposide
FDA
Food and Drug Administration
ITGB3
integrin beta‐3
MAPK
mitogen‐activated protein kinase
MMP2
matrix metalloproteinase‐2
MMP9
matrix metalloproteinase‐9
mRNA
messenger RNA
NF‐κB
nuclear factor kappa‐light‐chain‐enhancer of activated B cells
SBE
SMAD binding element
SERPINE1
serpin family E member 1
siRNA
small interfering RNA
ssGSEA
single‐sample gene set enrichment analysis
TCGA
The Cancer Genome Atlas
TGFβ
transforming growth factor beta
YAP
Yes‐associated protein
YAP8SA
mutants of inhibitory phosphorylation site at eight serine to Alanine of YAP
ZEB1
zinc finger E‐box binding homeobox 1
ZEB2
zinc finger E‐box‐binding homeobox 2
  相似文献   
34.
《Journal of vascular surgery》2020,71(6):1921-1929
ObjectiveIdentifying biomarkers for abdominal aortic aneurysms (AAA) could prove beneficial in prognosis of AAA and thus the selection for treatment. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein that is highly expressed in aorta. MFAP4 is involved in several tissue remodeling-related diseases. We aimed to investigate the potential role of plasma MFAP4 (pMFAP4) as a biomarker of AAA.MethodsPlasma samples and data were obtained for 504 male AAA patients and 188 controls in the Viborg Vascular (VIVA) screening trial. The pMFAP4 levels were measured by Alphalisa. The Mann-Whitney U test assessed differences in pMFAP4 levels between the presence and absence of different exposures of interest. The correlation between pMFAP4 and aorta growth rate were investigated through spearman's correlation analysis. Immunohistochemistry and multiple logistic regression adjusted for potential confounders assessed the association between pMFAP4 and AAA. Multiple linear regression assessed the correlation between pMFAP4 and aorta growth rate. Cox regression and competing risk regression were used to investigate the correlation between AAA patients with upper tertile pMFAP4 and the risk of undergoing later surgical repair.ResultsA significant negative correlation between pMFAP4 and aorta growth rate was observed using spearman's correlation analysis (ρ = −0.14; P = .0074). However, this finding did not reach significance when applying multiple linear regression. A tendency of decreased pMFAP4 was observed in AAA using immunohistochemistry. Competing risk regression adjusted for potential confounders indicated that patients with upper tertile pMFAP4 had a hazard ratio of 0.51 (P = .001) for risk of undergoing later surgical repair.ConclusionsHigh levels of pMFAP4 are associated with a decreased likelihood of receiving surgical repair in AAA. This observation warrants confirmation in an independent cohort.  相似文献   
35.

Purpose

Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.

Methods and Materials

First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.

Results

The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.

Conclusions

The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target.  相似文献   
36.
目的:探讨血清糖类抗原125(carbohydrate antigen 125,CA125)、人附睾蛋白4(human epididymis protein 4,HE4)、中性粒细胞与淋巴细胞比值(neutrophil-lymphocyte ratio,NLR)联合检测在子宫内膜癌诊断中的作用。方法:选取42例子宫内膜癌患者、50例子宫内膜良性疾病患者和50例健康体检人群。采用SYSMEX XN550全自动血液分析仪计数术前外周血中性粒细胞和淋巴细胞,计算NLR;采用Maglumi4000全自动化学发光仪检测术前血清CA125、HE4水平。采用ROC曲线分析CA125、HE4、NLR和三者联合指标在诊断子宫内膜癌中的作用。结果:外周血NLR在健康组、良性组和子宫内膜癌组中逐渐增高,且差异有统计学意义(P<0.05);子宫内膜癌组HE4表达量显著高于良性组与健康组(P<0.05),而良性组与健康组之间差异无统计学意义(P>0.05);CA125表达量在三组中差异无统计学意义(P>0.05)。CA125、HE4、NLR及三者联合标记物的AUC分别为0.530、0.733、0.795、0.823,当分别取它们的临界值时,特异性分别为70.8%、85.1%、61.7%、83.0%,敏感性分别为40.0%、63.3%、86.7%、73.3%。单项指标NLR的敏感性最高,HE4的特异性最高,联合指标的特异性和敏感性都很高。结论:术前血清CA125、HE4和NLR联合检测具有较高的特异性和敏感性,联合检测可以互为补充,提高子宫内膜癌的诊断准确率,对子宫内膜癌的诊断具有指导意义。  相似文献   
37.
A growing body of data suggests that therapies based on Toll-like receptors (TLR) targeting, in particular TLR4, holds promise in curing autoimmune and inflammatory pathologies still lacking specific treatment, included several rare diseases. While TLR4 activators (agonists) have already found successful clinical application as vaccine adjuvants, the use of TLR4 blockers (antagonists) as antisepsis agents or as agents against inflammatory diseases (including arthritis, multiple sclerosis, neuroinflammations) and cancer is still at a preclinical phase of development. This minireview focuses on recent achievements on the development of TLR4 modulators based on lipid A structure simplification, in particular on compounds having disaccharide or monosaccharide structures. As the TLR4 activity of natural TLR4 ligands (lipopolysaccharide, LPS and its biologically active part, the lipid A) depends on both the structure of endotoxin aggregates in solution and on single-molecule interaction with MD-2 and CD14 receptors, the rational design of TLR4 modulators should in principle take into account both these factors. In the light of the most recent advances in the field, in this minireview we discuss the structure–activity relationship in simplified lipid A analogs, with cationic or anionic amphiphilic structures.  相似文献   
38.
背景与目的:在前列腺癌标准化疗方案中,多西他赛(docetaxel,DTX)引起的化疗耐药是引起患者死亡的重要原因之一,然而DTX引起的化疗耐药相关机制尚未知。探讨前列腺癌DTX耐药的作用机制。方法:收集2016年6月—2019年6月在武汉市第三医院进行化疗的40例患者,包括20例DTX耐药和20例DTX敏感患者。人前列腺癌细胞系PC-3在一系列逐渐增加的DTX浓度梯度处理下形成耐药株PC-3/DTX。采用实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)检测miR-503和TLR4 mRNA的表达,采用蛋白质印迹法(Western blot)检测TLR4蛋白的水平,采用双荧光素酶报告基因检测miR-503和TLR4的相互作用,采用四甲基偶氮唑蓝(methyl thiazolyl tetrazolium,MTT)法检测细胞活力,采用流式细胞术检测细胞凋亡。结果:前列腺癌耐药患者组织和耐药细胞系中miR-503的表达较敏感组显著降低(P=0.013),而TLR4显著增加(P=0.005 6)。过表达miR-503显著抑制耐药细胞的增殖,促进凋亡,同时抑制耐药相关蛋白MDR-1的表达,而过表达TLR4则促进细胞的增殖,抑制凋亡,促进耐药相关蛋白MDR-1的表达。结论:miR-503通过靶向调控TLR4的表达影响前列腺癌的DTX耐药。  相似文献   
39.
Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders, including Huntington disease [caused by expanded CAG repeats (CAGr) in the HTT gene], and amyotrophic lateral sclerosis [ALS, possibly caused by expanded GGGGCC repeats (G4C2r) in the C9ORF72 gene], of which the molecular mechanisms remain unclear. Here, we demonstrated that lowering the Drosophila homologue of tau protein (dtau) significantly rescued in vivo neurodegeneration, motor performance impairments, and the shortened life-span in Drosophila expressing expanded CAGr or expanded G4C2r. Expression of human tau (htau4R) restored the disease-related phenotypes that had been mitigated by the loss of dtau, suggesting an evolutionarily-conserved role of tau in neurodegeneration. We further revealed that G4C2r expression increased tau accumulation by inhibiting autophagosome–lysosome fusion, possibly due to lowering the level of BAG3, a regulator of autophagy and tau. Taken together, our results reveal a novel mechanism by which expanded G4C2r causes neurodegeneration via an evolutionarily-conserved mechanism. Our findings provide novel autophagy-related mechanistic insights into C9ORF72-ALS and possible entry points to disease treatment.Electronic supplementary materialThe online version of this article (10.1007/s12264-020-00518-2) contains supplementary material, which is available to authorized users.  相似文献   
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