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71.
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.  相似文献   
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Cutaneous histiocytoses constitute a heterogeneous group of diseases characterised by the cutaneous accumulation of cells with the cytological and phenotypic features of macrophages or dendritic cells. The clinical spectrum ranges from self-resolving, skin-limited conditions to severe, multiorgan disease with a high morbidity rate. Until recently, cutaneous histiocytoses were classified according to the immunophenotype of the pathological cells, with differentiation between Langerhans cell histiocytosis (LCH) [CD1a+, CD207 (langerin)+] and non-Langerhans cell histiocytosis (CD68+, CD163+, CD1a?, CD207?). Over the last 12 years, a number of new pathophysiological findings (in particular, molecular pathology results) regarding histiocytoses have contributed to a new classification based on molecular alterations, as well as on clinical and imaging characteristics and the phenotype. The most frequent entities in children are juvenile xanthogranuloma and LCH.  相似文献   
74.
The formation of the external genitalia is a highly complex developmental process, considering it involves a wide range of cell types and results in sexually dimorphic outcomes. Development is controlled by several secreted signalling factors produced in complex spatiotemporal patterns, including the hedgehog (HH), bone morphogenic protein (BMP), fibroblast growth factor (FGF) and WNT signalling families. Many of these factors act on or are influenced by the actions of the androgen receptor (AR) that is critical to masculinisation. This complexity of expression makes it difficult to conceptualise patterns of potential importance. Mapping expression during key stages of development is needed to develop a comprehensive model of how different cell types interact in formation of external genitalia, and the global regulatory networks at play. This is particularly true in light of the sensitivity of this process to environmental disruption during key stages of development. The goal of this review is to integrate all recent studies on gene expression in early penis development to create a comprehensive spatiotemporal map. This serves as a resource to aid in visualising potentially significant interactions involved in external genital development.  相似文献   
75.
《Clinical breast cancer》2022,22(6):507-514
Breast cancer (BC) is a highly metastatic, pathological cancer that significantly affects women worldwide. The mortality rate of BC is related to its heterogeneity, aggressive phenotype, and metastasis. Recent studies have highlighted that the tumor microenvironment (TME) is critical for the interplay between metastasis mediators in BC. BC stem cells, tumor-derived exosomes, circulatory tumor cells (CTCs), and signaling pathways dynamically remodel the TME and promote metastasis. This review examines the cellular and molecular mechanisms governing the epithelial to mesenchymal transition (EMT) that facilitate metastasis. This review also discusses the role of cancer stem cells (CSCs), tumor-derived exosomes, and CTs in promoting BC metastasis. Furthermore, the review emphasizes major signaling pathways that mediate metastasis in BC. Finally, the interplay among CSCs, exosomes, and CTCs in mediating metastasis have been highlighted. Therefore, understanding the molecular cues that mediate the association of CSCs, exosomes, and CTCs in TME helps to optimize systemic therapy to target metastatic BC.  相似文献   
76.
目的探讨血清同型半胱氨酸(Hcy)、胰岛素样生长因子结合蛋白-1(IGFBP-1)联合检测对多囊卵巢综合征患者孕早期自然流产的预测价值。方法选取2018年3月—2020年5月行促排卵治疗并成功临床妊娠的多囊卵巢综合征165例,检测血清Hcy、IGFBP-1水平。根据孕早期自然流产发生情况分为孕早期自然流产组与未自然流产组,比较两组妊娠前一次促排卵后血清Hcy、IGFBP-1水平;多囊卵巢综合征患者孕早期自然流产的危险因素采用多因素Logistic回归分析,并采用受试者工作特征(ROC)曲线分析血清Hcy、IGFBP-1水平单项及联合检测对多囊卵巢综合征患者孕早期自然流产的预测价值。结果患者妊娠前一次促排卵后血清Hcy水平低于入院时,血清IGFBP-1水平高于入院时(P<0.01);自然流产组妊娠前一次促排卵后血清Hcy水平高于未自然流产组,血清IGFBP-1水平低于未自然流产组(P<0.01)。孕早期自然流产的发生率为28.48%。年龄≥35岁、多囊卵巢综合征分型、空腹胰岛素水平偏高、空腹血糖水平偏高、血清睾酮水平偏高、血清叶酸水平偏低、妊娠前一次促排卵后血清Hcy水平偏高及血清IGFBP-1水平偏低均是多囊卵巢综合征患者孕早期自然流产的危险因素(P<0.01)。妊娠前一次促排卵后血清Hcy水平联合血清IGFBP-1水平预测多囊卵巢综合征患者孕早期自然流产的敏感度、ROC曲线下面积均高于单独预测(P<0.01)。结论多囊卵巢综合征孕早期自然流产患者血清Hcy水平偏高,IGFBP-1水平偏低,二者均与多囊卵巢综合征患者孕早期自然流产密切相关,并对多囊卵巢综合征患者孕早期自然流产的发生具有较好的预测价值,联合检测时的预测效能更高。  相似文献   
77.
《Vaccine》2022,40(12):1872-1878
BackgroundThe MenB-FHbp vaccine (Trumenba®) is licensed in various countries for the prevention of meningococcal serogroup B disease in individuals ≥ 10 years of age. The clinical development program included 11 completed trials where, in each trial, MenB-FHbp had an acceptable safety profile after a primary vaccination series was administered to individuals 10–65 years of age. However, the detection of potential rare events was limited because of individual clinical trial size. The current safety analysis evaluates pooled reactogenicity and other adverse events (AEs) reported in these trials to identify new safety signals not detectable in individual trials.MethodsEleven trials contributed safety data, of which 10 recorded local and systemic reactogenicity events; 8 of the trials were controlled, and reactogenicity data were pooled for 7 of these 8 trials. Additional AE evaluations included immediate AEs (IAEs), medically attended AEs (MAEs), serious AEs (SAEs), newly diagnosed chronic medical conditions (NDCMCs), and autoimmune or neuroinflammatory conditions.ResultsLocal and systemic reactions were more frequent in the MenB-FHbp group (n = 15,294) compared with controls (n = 5509), although most reactions were transient and mild to moderate in severity. Frequencies of IAEs, SAEs, MAEs, NDCMCs, and autoimmune or neuroinflammatory conditions were similar between the MenB-FHbp and control groups.ConclusionsMenB-FHbp demonstrated a favorable safety and tolerability profile in the clinical development program of > 15,000 vaccine recipients ≥ 10 years of age. No new safety signals were identified in the pooled analysis compared with data from the individual trials. Continued postmarketing safety surveillance is important for the identification of rare events.Clinicaltrials.gov: NCT01299480; NCT000808028; NCT00879814; NCT00780806; NCT01352845; NCT01352793; NCT01461993; NCT01323270; NCT01830855; NCT01461980; NCT01768117.  相似文献   
78.
目的探讨解偶联蛋白1(UCP1)基因多态性与2型糖尿病(T2DM)心脑血管并发症的相关性。方法选取2019年7月—2020年7月住院治疗的T2DM 440例,根据有无心脑血管并发症分为观察组(T2DM合并心脑血管并发症)221例和对照组(单纯T2DM)219例。比较两组一般资料,UCP1在rs45539933、rs10011540及rs1800592位点的基因型分布与等位基因频率;通过多因素Logistic回归分析评估T2DM发生心脑血管事件的危险因素。结果观察组病程长于对照组,糖化血红蛋白水平高于对照组,而血清高密度脂蛋白胆固醇水平低于对照组(P<0.01)。观察组C/C基因型分布及C碱基频率均高于对照组(P<0.05)。C/C基因型是T2DM患者发生心脑血管并发症的危险因素(P<0.05)。结论UCP1基因多态性与T2DM心脑血管并发症的发生显著相关。  相似文献   
79.
Inside and outside the brain, accumulation of amyloid fibrils plays key roles in the pathogenesis of fatal age-related diseases such as Alzheimer’s and Parkinson’s diseases and wild-type transthyretin amyloidosis. Although the incidence of all amyloidoses increases with age, for some types of amyloidosis aging is known as the main direct risk factor, and these types are typically diseases of elderly people. More than 10 different precursor proteins are known to cause age-associated amyloidosis; these proteins include amyloid β protein, α-synuclein, transthyretin, islet amyloid polypeptide, atrial natriuretic factor, and the newly discovered epidermal growth factor-containing fibulin-like extracellular matrix protein 1. Except for intracerebral amyloidoses, most age-related amyloidoses have been little studied. Indeed, in view of the increasing life expectancy in our societies, understanding how aging is involved in the process of amyloid fibril accumulation and the effects of amyloid deposits on the aging body is extremely important. In this review, we summarize current knowledge about the nature of amyloid precursor proteins, the prevalence, clinical manifestations, and pathogenesis of amyloidosis, and recent advances in our understanding of age-related amyloidoses outside the brain.  相似文献   
80.
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