Two amino acids near the N‐terminus of Cucumber mosaic virus 2b play critical roles in the suppression of RNA silencing and viral infectivity

Cucumber mosaic virus (CMV) 2b suppresses RNA silencing primarily through the binding of double‐stranded RNA (dsRNA) of varying sizes. However, the biologically active form of 2b remains elusive. Here, we demonstrate that the single and double alanine substitution mutants in the N‐terminal 15th leucine and 18th methionine of CMV 2b exhibit drastically attenuated virulence in wild‐type plants, but are efficiently rescued in mutant plants defective in RNA‐dependent RNA polymerase 6 (RDR6) and Dicer‐like 4 (DCL4). Moreover, the transgenic plants of 2b, but not 2blm (L15A/M18A), rescue the high infectivity of CMV‐Δ2b through the suppression of antiviral silencing. L15A, M18A or both weaken 2b suppressor activity on local and systemic transgene silencing. In contrast with the high affinity of 2b to short and long dsRNAs, 2blm is significantly compromised in 21‐bp duplex small interfering RNA (siRNA) binding ability, but maintains a strong affinity for long dsRNAs. In cross‐linking assays, 2b can form dimers, tetramers and oligomers after treatment with glutaraldehyde, whereas 2blm only forms dimers, rather than tetramers and oligomers, in vitro. Together, these findings suggest that L15 and M18 of CMV 2b are required for high affinity to ds‐siRNAs and oligomerization activity, which are essential for the suppression activity of 2b on antiviral silencing.     

CD80、CD86在鼻咽癌中的表达及其临床病理意义

目的:研究CD80、CD86在鼻咽癌中的表达变化及其临床病理意义。方法:选择2014年10月至2018年10月本院接诊的鼻咽癌确诊患者64例纳入研究,依据鼻咽癌复发情况分复发组(n=30)和未复发组(n=34);同期选取正常鼻粘膜活检组织33例作为正常对照组,采用SP免疫组化法检测鼻咽癌患者癌组织或正常鼻粘膜活检组织CD80、CD86蛋白的表达,并经Spearman相关性分析法分析CD80、CD86蛋白表达与鼻咽癌恶化程度的相关性。结果:鼻咽癌的癌组织CD80、CD86蛋白均呈高表达,阳性表达主要定位于细胞膜、细胞质,与肿瘤临床TNM分期、淋巴结转移均显著相关(P0.05)。复发组、未复发组肿瘤组织中的mRNA(ARD1、Ptch1、Survivin)表达显著高于对照组,且复发组高于未复发组,差异有统计学意义(P0.05)。Spearman相关性分析显示CD80、CD86蛋白表达与鼻咽癌细胞侵袭能力呈显著正相关(r=0.403、0.547,P0.05)。结论:鼻咽癌的癌组织内CD80、CD86蛋白均呈高表达,与鼻咽癌的临床分期、淋巴结转移及放疗预后关系密切,可能作鼻咽癌临床诊治及预后评估的重要参考指标。     

Multiomic Metabolic Enrichment Network Analysis Reveals Metabolite–Protein Physical Interaction Subnetworks Altered in Cancer

Metabolism is recognized as an important driver of cancer progression and other complex diseases, but global metabolite profiling remains a challenge. Protein expression profiling is often a poor proxy since existing pathway enrichment models provide an incomplete mapping between the proteome and metabolism. To overcome these gaps, we introduce multiomic metabolic enrichment network analysis (MOMENTA), an integrative multiomic data analysis framework for more accurately deducing metabolic pathway changes from proteomics data alone in a gene set analysis context by leveraging protein interaction networks to extend annotated metabolic models. We apply MOMENTA to proteomic data from diverse cancer cell lines and human tumors to demonstrate its utility at revealing variation in metabolic pathway activity across cancer types, which we verify using independent metabolomics measurements. The novel metabolic networks we uncover in breast cancer and other tumors are linked to clinical outcomes, underscoring the pathophysiological relevance of the findings.     

Apoptosis in anititumor strategies: Modulation of cell cycle or differentiation

There is a strong evidence that administration of antitumor drugs triggers apoptotic death of target cells. A characteristic feature of appotosis is active participation of the affected cell in its demise. Attempts have been made, therefore, to potentiate the cytotoxicity of a variety of agents by modulating the propensity of cells to respond by apoptosis. Several strategies to enhance apoptosis that involve modulation of the cell cycle or differentiation are discussed. Loss of control of the G₁ checkpoint in tumor cells allows one to design treatments that arrest normal cells at the checkpoint and attempt to selectively kill tumor cells with S phase specific drugs. The possibility of a restoration of the apoptosis triggering function of the tumor suppressor gene p53 when the G₁ checkpoint function is abolished is expected to increase tumor cells' sensitivity to S phase poisons. Because induction of apoptosis by many antitumor drugs is cell cycle phase specific, drug combinations that preferentially trigger apoptosis at different phases of the cycle, or recruitment of cells to the sensitive phase, offer another antitumor strategy. There is also evidence that apoptosis is potentiated when cell differentiation is triggered follwing DNA damage. This observation suggests that strategies which combine DNA damaging and differentiating drugs, under conditions where the latter are administered following DNA damage caused by the former, may be successful.     

Tumor-suppressive effects of psoriasin (S100A7) are mediated through the β-catenin/T cell factor 4 protein pathway in estrogen receptor-positive breast cancer cells

Psoriasin (S100A7) is expressed in several epithelial malignancies including breast cancer. Although S100A7 is associated with the worst prognosis in estrogen receptor α-negative (ERα(-)) invasive breast cancers, its role in ERα-positive (ERα(+)) breast cancers is relatively unknown. We investigated the significance of S100A7 in ERα(+) breast cancer cells and observed that S100A7 overexpression in ERα(+) breast cancer cells, MCF7 and T47D, exhibited decreased migration, proliferation, and wound healing. These results were confirmed in vivo in nude mouse model system. Mice injected with S100A7-overexpressing MCF7 cells showed significant reduction in tumor size compared with mice injected with vector control cells. Further mechanistic studies revealed that S100A7 mediates the tumor-suppressive effects via a coordinated regulation of the β-catenin/TCF4 pathway and an enhanced interaction of β-catenin and E-cadherin in S100A7-overexpressing ERα(+) breast cancer cells. We observed down-regulation of β-catenin, p-GSK3β, TCF4, cyclin D1, and c-myc in S100A7-overexpressing ERα(+) breast cancer cells. In addition, we observed increased expression of GSK3β. Treatment with GSK3β inhibitor CHIR 99021 increased the expression of β-catenin and its downstream target c-myc in S100A7-overexpressing cells. Tumors derived from mice injected with S100A7-overexpressing MCF7 cells also showed reduced activation of the β-catenin/TCF4 pathway. Therefore, our studies reveal for the first time that S100A7-overexpressing ERα(+) breast cancer cells exhibit tumor suppressor capabilities through down-modulation of the β-catenin/TCF4 pathway both in vitro and in vivo. Because S100A7 has been shown to enhance tumorigenicity in ERα(-) cells, our studies suggest that S100A7 may possess differential activities in ERα(+) compared with ERα(-) cells.     

康力欣胶囊联合FOLFOX4方案对中晚期胃癌患者免疫功能、生活质量和血清肿瘤标志物的影响

目的:观察康力欣胶囊联合奥沙利铂、亚叶酸钙、5-氟尿嘧啶(FOLFOX4)方案对中晚期胃癌患者免疫功能、生活质量和血清肿瘤标志物的影响。方法:前瞻性选取2018年7月~2021年1月期间来我院接受治疗的胃癌患者80例,根据抽签分为对照组和观察组两组,各为40例。对照组接受FOLFOX4方案治疗,观察组接受康力欣胶囊联合FOLFOX4方案治疗,以3周为1个疗程,治疗2个疗程。观察两组治疗2个疗程后的疗效、生活质量以及治疗期间不良反应状况,对比两组治疗前、治疗2个疗程后的肿瘤标志物和免疫功能指标变化情况。结果:观察组治疗2个疗程后的总有效率高于对照组(P<0.05)。治疗2个疗程后,观察组的肿瘤相关物质群(TSGF)、糖类抗原-199(CA-199)、癌胚抗原(CEA)低于对照组(P<0.05)。治疗2个疗程后,观察组的CD3;、CD4;、自然杀伤细胞(NK)、CD4;/CD8;高于对照组,CD8;低于对照组(P<0.05)。治疗2个疗程后,观察组的生活质量总改善率、卡氏评分(KPS)评分高于对照组(P<0.05)。两组不良反应发生率组间对比无统计学差异(P>0.05)。结论:中晚期胃癌患者采用康力欣胶囊联合FOLFOX4方案治疗,在阻止疾病进展、改善生活质量、提高免疫功能方面均效果确切,优于单纯化疗效果。     

TGM2对胃癌细胞BGC-823增殖、迁移和侵袭能力的影响

目的:转谷氨酰胺酶-2(transglutaminase-2,TGM2)是一种多功能的蛋白,在乳腺癌,胰腺癌,黑色素瘤和前列腺癌等肿瘤中高表达,而且和肿瘤的增殖和转移密切相关。本研究旨在探索TGM2对胃癌细胞BGC-823的增殖、迁移和侵袭能力的影响。方法:q RT-PCR、蛋白质印迹及免疫组化检测TGM2在胃癌细胞及组织中的表达情况;慢病毒转染胃癌细胞BGC-823以干扰TGM2的表达,荧光显微镜下观察转染效率,蛋白质印迹检测TGM2表达干扰效果;CCK-8法检测TGM2下调对BGC-823增殖能力的影响;Transwell法检测TGM2下调对BGC-823的迁移和侵袭能力影响;蛋白质印迹检测TGM2下调对转移和凋亡相关蛋白表达的影响。结果:TGM2在胃癌细胞和组织中均高表达,P0.01(q RT-PCR),P0.001(免疫组化);转染慢病毒后,荧光显微镜下观察结果显示转染效率超过90%,蛋白质印迹结果显示实验组sh TGM2-1的干扰效果最好,TGM2明显下调,差异具有统计学意义,P0.0001;CCK-8结果表明TGM2下调后,从细胞铺板第2d开始,实验组(sh TGM2-1)的细胞增殖倍数明显下降,P0.05(2d),P0.01(3d),P0.001(4d),P0.01(5d);Transwell结果显示,TGM2下调后,BGC-823的迁移和侵袭能力明显减弱,P0.001(迁移),P0.01(侵袭);蛋白质印迹结果显示,TGM2下调后,NF-κB和Bcl-2表达下调,而Bax表达上调,P0.05(NF-κB)、P0.001(Bcl-2)和P0.0001(Bax)。结论:TGM2下调能抑制胃癌细胞BGC-823的增殖、迁移和侵袭能力,并和NF-κB、Bcl-2的下调以及和Bax的表达水平上调有关,为胃癌的临床治疗提供了新靶点。     

特罗凯靶向治疗联合培美曲塞和顺铂对非小细胞肺癌患者血清肿瘤标志物、免疫球蛋白和T淋巴细胞亚群的影响

摘要 目的：探讨特罗凯靶向治疗联合培美曲塞和顺铂对非小细胞肺癌（NSCLC）患者血清肿瘤标志物、免疫球蛋白和T淋巴细胞亚群的影响。方法：选取2018年2月~2020年2月期间我院接收的NSCLC患者80例,采用抽签法分为对照组、观察组两组,各40例。对照组给予培美曲塞和顺铂化疗方案治疗,观察组在对照组基础上联合特罗凯靶向治疗,对比两组总有效率、血清肿瘤标志物、免疫球蛋白、T淋巴细胞亚群及不良反应发生率。结果：对比两组不良反应无差异（P>0.05）。治疗3个疗程后,对照组、观察组的临床总有效率分别为37.50%、60.00%,观察组的总有效率高于对照组（P<0.05）。治疗3个疗程,观察组CD3⁺、CD4⁺、CD4⁺/CD8⁺高于对照组,CD8⁺低于对照组（P<0.05）。治疗3个疗程,观察组免疫球蛋白G（IgG）、免疫球蛋白A（IgA）、免疫球蛋白M（IgM）高于对照组（P<0.05）。治疗3个疗程,观察组细胞角蛋白19片段（CYFRA21-1）、糖类抗原50（CA50）、癌胚抗原（CEA）低于对照组（P<0.05）。结论：特罗凯靶向治疗联合培美曲塞和顺铂治疗NSCLC患者,疗效较好,可能与该方案可降低患者血清肿瘤标志物含量、调节免疫应答等因素有关。     

Chemopreventive and Antioxidant Activity of the Chamazulene‐Rich Essential Oil Obtained from Artemisia arborescens L. Growing on the Isle of La Maddalena,Sardinia, Italy

The essential oils of Artemisia arborescens growing in Sardinia (Italy), collected during three plant growth stages, i.e., from the vegetative stage to post‐blooming time, were characterized. Moreover, the in vitro antiproliferative and antioxidant activities of the oil isolated from aerial parts collected in February were evaluated. The essential oils belonged to the β‐thujone/chamazulene chemotype, notably with the highest amount of chamazulene (ca. 52%) ever detected up to now in the genus Artemisia and, in general, in essential oils. Quantitative variations in the oil composition were observed as the plant passes from the vegetative to the blooming stage. The oil was tested for its potential tumor cell growth‐inhibitory effect on T98G, MDA‐MB 435S, A375, and HCT116 human cell lines, using the MTT (=3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) assay. The highest activity was observed on A375 and HCT116 cell lines, with IC₅₀ values of 14 μg/ml. Moreover, the in vitro antioxidant and free radical‐scavenging assays revealed the oil to be an effective scavenger of the ABTS radical cation, with an activity comparable to that of Trolox^®. These results support the use of A. arborescens oil for the treatment of inflamed skin conditions. Finally, the composition of the polar fraction of the A. arborescens aerial parts was also examined, and the main component detected was 5‐O‐caffeoylquinic acid, which was identified for the first time in this plant.