大黄酸通过抑制STAT3基因的表达调控骨肉瘤细胞的增殖和凋亡

目的:探讨大黄酸对骨肉瘤细胞增殖和凋亡的影响及潜在的作用机制。方法:以人骨肉瘤MG-63细胞为研究对象，利用CCK-8实验检测大黄酸对MG-63细胞增殖的影响，并计算大黄酸作用48 h的半数抑制浓度（IC50），采用该浓度进行后续的实验。转染STAT3 siRNA至MG-63细胞，qRT-PCR和Western blot检测分别在mRNA和蛋白水平上检测转染效果，采用CCK-8实验、克隆形成实验、流式细胞术验证大黄酸和STAT3 siRNA及其联合作用对MG-63细胞存活率、克隆形成、凋亡能力的影响，Western blot检测各组MG-63细胞中凋亡相关蛋白Bax、Bcl-2、Cleaved Caspase-3的表达情况。结果:大黄酸能够呈浓度依赖性的抑制骨肉瘤MG-63细胞增殖，干预48 h的IC50为46.05 μmol/L。大黄酸或STAT3 siRNA均能降低MG-63细胞中STAT3的表达，抑制MG-63细胞存活率，阻碍细胞克隆形成能力，促进细胞凋亡，上调细胞中Bax和Cleaved Caspase-3的表达，下调Bcl-2的表达；且二者联合效果更显著。结论:大黄酸通过抑制STAT3基因表达抑制骨肉瘤细胞增殖并促进细胞凋亡。     

STAT1 gain-of-function and chronic demodicosis

Heterozygous STAT1 gain-of-function (GOF) mutations result in a combined form of immunodeficiency which is the most common genetic cause of chronic mucocutaneous candidiasis (CMC). We present a pedigree with a GOF mutation in STAT1, manifesting with chronic demodicosis in the form of a facial papulopustular eruption, blepharitis, and chalazion. So far, demodicosis has been described in only one family with STAT1-GOF mutation. We suggest that chronic demodicosis is an under-recognized feature of the immune dysregulation disorder caused by STAT1 gain-of-function mutations.     

Thromboses et thrombopathies dans les syndromes myéloprolifératifs

Myeloproliferative neoplasms are acquired hematological malignancies, mainly affecting the adult and whose morbidity and mortality stems from haemostasis disorders. The most frequently encountered complications include thrombosis, affecting preferentially the arterial territory, but also atypical locations such as splanchnic vein thrombosis. The pathophysiology of these thromboses is complex and involves different actors: blood cells, endothelium and flow conditions. Numerous studies have been conducted to identify risk factors for thrombosis. To date, only two risk factors have been validated through prospective studies (age over 60 years old, history of thrombotic events) and allow classification of patients as “low risk” and “high risk” as the basis for current treatment recommendations. Haemorrhagic manifestations, less frequent than thrombosis, are mainly related to an alteration of primary haemostasis and are therefore manifested by mucocutaneous bleeding. In these patients, platelet dysfunctions and/or acquired Willebrand syndromes can be found. The pathophysiology of thrombosis and platelet dysfunction during myeloproliferative neoplasms remains to date partially unknown. In this review, we offer to focus on physiopathological mechanisms as well as the latest advances in their understanding.     

Epithelial STAT6 O-GlcNAcylation drives a concerted anti-helminth alarmin response dependent on tuft cell hyperplasia and Gasdermin C

1. Download : Download high-res image (137KB)
2. Download : Download full-size image

     

Decoding signaling pathways involved in prolactin-induced neuroprotection: A review

It has been well recognized that prolactin (PRL), a pleiotropic hormone, has many functions in the brain, such as maternal behavior, neurogenesis, and neuronal plasticity, among others. Recently, it has been reported to have a significant role in neuroprotection against excitotoxicity. Glutamate excitotoxicity is a common alteration in many neurological and neurodegenerative diseases, leading to neuronal death. In this sense, several efforts have been made to decrease the progression of these pathologies. Despite various reports of PRL’s neuroprotective effect against excitotoxicity, the signaling pathways that underlie this mechanism remain unclear. This review aims to describe the most recent and relevant studies on the molecular signaling pathways, particularly, PI3K/AKT, NF-κB, and JAK2/STAT5, which are currently under investigation and might be implicated in the molecular mechanisms that explain the PRL effects against excitotoxicity and neuroprotection. Remarkable neuroprotective effects of PRL might be useful in the treatment of some neurological diseases.     

Downregulation of APRIN expression increases cancer cell proliferation via an interleukin-6/STAT3/cyclin D axis

APRIN is a putative tumor suppressor whose expression is low in a variety of cancer cells. While decreased expression of APRIN leads to increased cell proliferation, unfavorable diagnosis or metastases in various cancer types, there is limited knowledge on the cellular mechanism of APRIN in cellular responses. The effect of APRIN depletion on cancer cell proliferation was examined in the present study, and the IL-6/STAT3/cyclin D axis was identified as a novel regulatory mechanism. Stable depletion of APRIN in cancer cells resulted in increased cell proliferation. Cytokine array analysis of the cells revealed that downregulation of APRIN induced secretion of interleukin-6 (IL-6) with corresponding activation of STAT3, a downstream intracellular mediator. Levels of cyclin D1 were increased in cells with APRIN depletion and cyclin D1 expression was associated with increased STAT3 binding on cyclin D1 promoter sequence; assessed by chromatin immunoprecipitation assay. The addition of an IL-6 neutralizing antibody P620 to the cell culture attenuated STAT3 activation and cyclin D1 expression in APRIN-depleted cells with corresponding decrease in cell proliferation. These experiments suggest that APRIN regulates cancer cell proliferation via an IL-6/STAT3/cyclin D axis and that targeting this axis in APRIN-associated cancer might provide a novel therapeutic approach.     

Targeting autophagy in colorectal cancer: An update on pharmacological small-molecule compounds

Autophagy, an evolutionarily highly conserved cellular degradation process, plays the Janus role (either cytoprotective or death-promoting) in colorectal cancer, so the targeting of several key autophagic pathways with small-molecule compounds may be a new therapeutic strategy. In this review, we discuss autophagy-associated cell death pathways and key cytoprotective autophagy pathways in colorectal cancer. Moreover, we summarize a series of small-molecule compounds that have the potential to modulate autophagy-associated cell death or cytoprotective autophagy for therapeutic purposes. Taken together, these findings demonstrate the Janus role of autophagy in colorectal cancer, and shed new light on the exploitation of a growing number of small-molecule compounds to target autophagy in future cancer drug discovery.     

Effect of Diacerein on HOTAIR/IL-6/STAT3, Wnt/β-Catenin and TLR-4/NF-κB/TNF-α axes in colon carcinogenesis

Colorectal cancer (CRC) is a common malignancy with high mortality and poor prognosis. Diacerein (DIA) is an anti-inflammatory used for treatment of osteoarthritis. We delineated some underlying molecular mechanisms of DIA’s anti-carcinogenic effect in CRC using in vivo and in vitro models. Human Caco-2 cells were treated with DIA followed by MTT and Annexin V assays and CRC was experimentally induced using 1,2-dimethylhydrazine. DIA (50 mg/kg/day, orally) was administrated for 8 weeks. The MTT assay confirmed cytotoxic effect of DIA in vitro and Annexin V confirmed its apoptotic effect. DIA resulted in regression of tumour lesions with reduced colonic TLR4, NF-κB and TNF-α protein levels and down-regulated VEGF expression, confirming anti-angiogenic impact. DIA triggered caspase-3 expression and regulated Wnt/β-Catenin pathway, by apparently interrupting the IL-6/STAT3/ lncRNA HOTAIR axis. In conclusion, DIA disrupted IL-6/STAT3/ lncRNA HOTAIR axis which could offer an effective therapeutic strategy for the management of CRC.     

骨髓增殖性肿瘤研究进展:JAK2 V617F基因突变发现后10年

结合大量的临床实践和近10年来对骨髓增殖性肿瘤(MPN)[骨髓增殖性疾病(MPD)]在JAK2 V617F基因突变等分子水平的大量研究,更加深了对MPN(MPD)的分子发病机制和临床价值的认识.研究者们探讨了JAK2 V617F基因突变如何促进MPN(MPD)发病的机制,分析了JAK2 V617F基因突变的分子机制和JAK2 V617F基因突变如何引起MPN(MPD)不同临床表型,以及MPN(MPD)基因组突变图谱及其生物学意义,指出了MPN(MPD)病理克隆的复杂性.JAK2 V617F基因突变在研究和诊治MPN(MPD)的过程中发挥着重大作用,其促使MPN(MPD)的研究和应用深入到基因/分子水平,治疗更趋于靶向性,更加精确,特别是使那些常规检验无法明确诊断的患者获得了及时诊治,避免了合并疾病的发生.MPN(MPD)的防治焦点是及时诊治,预防并避免血栓/出血性并发症的发生.推荐首选干扰素α(IFN-α)治疗,对于年龄大于60岁的患者,羟基脲是可以采用的.MPN(MPD)患者的预后大多数良好,发生恶变的风险不高,这是反复建议对中国MPD患者避免使用MPN称谓的主要理由.