Aberrant expression

异常表达式
  • 文章类型: Journal Article
    基因错误表达是在通常无活性的情况下基因的异常转录。尽管已知其在特定罕见疾病中的病理后果,我们对其在人类中的广泛流行和机制了解有限。为了解决这个问题,我们分析了来自INTERVAL研究献血者的4,568份全血批量RNA测序样本中的基因错误表达.我们发现,虽然个别错误表达事件很少发生,总的来说,它们存在于几乎所有的样本和三分之一的无活性蛋白质编码基因中。使用2,821个配对的全基因组和RNA测序样本,我们发现,对于罕见的结构变异体,错误表达事件富含顺式.我们建立了推测的机制,通过这些机制,SVs的一个子集导致基因错误表达,包括转录通读,转录融合,和基因倒位。总的来说,我们开发了错误表达作为转录组异常分析的一种类型,并扩展了我们对遗传变异影响基因表达的各种机制的理解。
    Gene misexpression is the aberrant transcription of a gene in a context where it is usually inactive. Despite its known pathological consequences in specific rare diseases, we have a limited understanding of its wider prevalence and mechanisms in humans. To address this, we analyzed gene misexpression in 4,568 whole-blood bulk RNA sequencing samples from INTERVAL study blood donors. We found that while individual misexpression events occur rarely, in aggregate they were found in almost all samples and a third of inactive protein-coding genes. Using 2,821 paired whole-genome and RNA sequencing samples, we identified that misexpression events are enriched in cis for rare structural variants. We established putative mechanisms through which a subset of SVs lead to gene misexpression, including transcriptional readthrough, transcript fusions, and gene inversion. Overall, we develop misexpression as a type of transcriptomic outlier analysis and extend our understanding of the variety of mechanisms by which genetic variants can influence gene expression.
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  • 文章类型: Journal Article
    背景:罕见的致癌驱动事件,特别是影响驱动基因的表达或剪接,被怀疑在很大程度上导致了血液系统恶性肿瘤的巨大异质性。然而,他们的身份仍然具有挑战性。
    方法:要解决此问题,我们收集了迄今为止最大的数据集,对来自3760例患者的24个疾病实体的血液系统恶性肿瘤进行了匹配的全基因组测序和总RNA测序.利用我们的数据集大小,我们专注于发现罕见的监管异常。因此,我们使用工作流程DROP(RNA异常值检测管道)和AbSplice的扩展来调用表达和剪接异常值,一种变异效应预测因子,可识别导致异常剪接的遗传变异。接下来,我们训练了一个整合这些结果的机器学习模型,以优先考虑新的候选疾病特异性驱动基因。
    结果:我们发现了七个异常表达基因的中位数,两个剪接离群基因,和每个样本两个罕见的影响剪接的变体。每个类别都显示出对已经充分表征的驱动基因的显着富集,在超过五个样本的基因中,比值比超过三个。根据保留的数据,我们的综合建模显著优于仅基于基因组数据的建模,并揭示了有前景的新型候选驱动基因.值得注意的是,我们发现低密度脂蛋白受体LRP1B转录物的截短形式在大约一半的毛细胞白血病变体(HCL-V)样品中异常过表达,在较小程度上,密切相关的B细胞肿瘤。这个观察,这在一个独立的队列中得到了证实,提示LRP1B是HCL-V亚类的新标记物,LRP1B在这些稀有实体中的功能作用尚未报道。
    结论:总而言之,我们对24个血液恶性肿瘤实体的表达和剪接异常值的普查以及伴随的计算工作流程构成了独特的资源,可以加深我们对血液肿瘤中罕见致癌事件的理解.
    Rare oncogenic driver events, particularly affecting the expression or splicing of driver genes, are suspected to substantially contribute to the large heterogeneity of hematologic malignancies. However, their identification remains challenging.
    To address this issue, we generated the largest dataset to date of matched whole genome sequencing and total RNA sequencing of hematologic malignancies from 3760 patients spanning 24 disease entities. Taking advantage of our dataset size, we focused on discovering rare regulatory aberrations. Therefore, we called expression and splicing outliers using an extension of the workflow DROP (Detection of RNA Outliers Pipeline) and AbSplice, a variant effect predictor that identifies genetic variants causing aberrant splicing. We next trained a machine learning model integrating these results to prioritize new candidate disease-specific driver genes.
    We found a median of seven expression outlier genes, two splicing outlier genes, and two rare splice-affecting variants per sample. Each category showed significant enrichment for already well-characterized driver genes, with odds ratios exceeding three among genes called in more than five samples. On held-out data, our integrative modeling significantly outperformed modeling based solely on genomic data and revealed promising novel candidate driver genes. Remarkably, we found a truncated form of the low density lipoprotein receptor LRP1B transcript to be aberrantly overexpressed in about half of hairy cell leukemia variant (HCL-V) samples and, to a lesser extent, in closely related B-cell neoplasms. This observation, which was confirmed in an independent cohort, suggests LRP1B as a novel marker for a HCL-V subclass and a yet unreported functional role of LRP1B within these rare entities.
    Altogether, our census of expression and splicing outliers for 24 hematologic malignancy entities and the companion computational workflow constitute unique resources to deepen our understanding of rare oncogenic events in hematologic cancers.
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  • 文章类型: Journal Article
    急性髓性白血病(AML)是由获得性致癌突变引起的造血祖细胞肿瘤,阻碍分化,导致骨髓中未成熟髓母细胞的积累。异常表型是其中淋巴相关和其他骨髓谱系标记在成髓细胞中表达或髓样相关标记在成淋巴细胞中表达的现象。
    本研究包括AML的诊断病例,以使用多参数流式细胞术研究异常表达。
    在50个样本量中,有30个病例表达异常CD标记。男性:女性比例为0.76。大多数病例属于年龄>60岁的年龄组。CD7是最常见的异常CD标记。
    在缺乏细胞遗传学等更先进的诊断工具的情况下,免疫表型分型在造血系统恶性肿瘤的诊断和预测预后中具有重要作用。
    UNASSIGNED: Acute myeloid leukaemia (AML) is a tumour of hematopoietic progenitors caused by acquired oncogenic mutations that impede differentiation, leading to the accumulation of immature myeloid blasts in the marrow. Aberrant phenotype is a phenomenon in which lymphoid-associated and other myeloid lineage markers are expressed in myeloblasts or myeloid-associated markers are expressed in lymphoblasts.
    UNASSIGNED: Diagnosed cases of AML were included in this study to study the aberrant expression using multiparametric flow cytometry.
    UNASSIGNED: Out of a sample size of 50, 30 cases expressed aberrant CD markers. Male: Female ratio was 0.76. Majority of cases belonged to the age group >60 years of age. CD 7 was overall the most common aberrant CD marker.
    UNASSIGNED: Immunophenotyping has a significant role in diagnosis and predicting prognosis of hematopoietic malignancies in the absence of more advanced diagnostic tools like cytogenetics.
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  • 文章类型: Journal Article
    卵巢癌是女性生殖体系中最具侵袭性和显著的恶性肿瘤形式之一。由于其转移,它是妇科癌症中死亡的主要原因。由于它缺乏初步的疾病症状,必须开发早期诊断生物标志物,以帮助优化治疗和个性化.在这种情况下,microRNAs,它们是短序列非编码分子,显示出作为高度特异性和敏感性生物标志物的巨大潜力。miRNA已被广泛提倡并证明在癌症的临床管理中起重要作用。尤其是卵巢癌,通过促进癌细胞的发展,入侵,细胞凋亡延迟,上皮-间质转化,癌细胞转移,化学敏感性和耐药性与疾病治疗。这里,我们涵盖了我们目前对最新的基于microRNA的检测卵巢癌的方法的理解,以及当前的诊断和治疗策略,microRNAs作为癌基因或肿瘤抑制基因的作用,以及它们在卵巢癌进展中的意义,预后,和治疗。
    Ovarian cancer is one of the most aggressive and significant malignant tumor forms in the female reproductive system. It is the leading cause of death among gynecological cancers owing to its metastasis. Since its preliminary disease symptoms are lacking, it is imperative to develop early diagnostic biomarkers to aid in treatment optimization and personalization. In this vein, microRNAs, which are short sequence non-coding molecules, displayed great potential as highly specific and sensitive biomarker. miRNAs have been extensively advocated and proven to serve an instrumental part in the clinical management of cancer, especially ovarian cancer, by promoting the cancer cell progression, invasion, delayed apoptosis, epithelial-mesenchymal transition, metastasis of cancer cells, chemosensitivity and resistance and disease therapy. Here, we cover our present comprehension of the most up-to-date microRNA-based approaches to detect ovarian cancer, as well as current diagnostic and treatment strategies, the role of microRNAs as oncogenes or tumor suppressor genes, and their significance in ovarian cancer progression, prognosis, and therapy.
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  • 文章类型: Journal Article
    目的:单纯从临床和形态学上区分高级别前列腺癌(PCa)与低分化尿路上皮癌(UC)可能具有一定的挑战性。然而,它对预后和治疗选择非常重要。GATA3是证实尿路上皮起源的有用免疫组织化学标记物。然而,最近的工作报告在原发性高级别PCa中具有很强的GATA3免疫表达。这项研究的目的是探索GATA3在转移性PCa中的特异性表达。
    结果:查询了四个大专院校的病理学数据库中的转移性PCa病例。由经验丰富的泌尿生殖道病理学家审查了可用的幻灯片和临床记录。前列腺标志物(PSA,PSAP,进行NKX3.1)和GATA3免疫组织化学。共纳入163例转移性PCa病例。在非区域远处转移的每个病例中至少有一个前列腺标志物是阳性的,确认前列腺起源。在4例(2.5%)中发现GATA3强染色:两个肝脏,一个骨和一个非区域淋巴结转移。所有4名患者在初始诊断时具有5级PCa组。转移性前列腺腺癌是实性的,没有腺体形成(n=3)或仅有局灶性卷曲形成(n=1)。
    结论:据我们所知,这是首次探索GATA3在转移性PCa中表达的特异性研究。尽管很少,高级别PCa中GATA3阳性可能导致误诊,具有临床意义。我们推荐一组免疫组织化学标记,前列腺和尿路上皮,排除UC,无论是在原发肿瘤样本中,还是在未知原发转移的情况下,当怀疑泌尿生殖系统起源时。
    OBJECTIVE: The distinction of high-grade prostate cancer (PCa) from poorly differentiated urothelial carcinoma (UC) can be somewhat challenging on clinical and morphological grounds alone, yet it is of great importance for prognostication and choice of treatment. GATA3 is a useful immunohistochemical marker to confirm urothelial origin. However, recent works report strong GATA3 immunoexpression in primary high-grade PCa. The aim of this study was to explore GATA3 expression specifically in metastatic PCa.
    RESULTS: The pathology databases of four tertiary institutions were queried for cases of metastatic PCa. Available slides and clinical records were reviewed by experienced genitourinary pathologists. Prostatic markers (PSA, PSAP, NKX3.1) and GATA3 immunohistochemistry were performed. A total of 163 metastatic PCa cases were included. At least one prostate marker was positive in each case of non-regional distant metastasis, confirming prostatic origin. GATA3 strong staining was found in four (2.5%) cases: two liver, one bone and one non-regional lymph-node metastases. All four patients had Grade Group 5 PCa at the initial diagnosis. The metastatic prostatic adenocarcinomas were solid, either with no gland formation (n = 3) or with only focal cribriforming (n = 1).
    CONCLUSIONS: To our knowledge, this is the first study exploring GATA3 expression specifically in metastatic PCa. Despite being infrequent, GATA3 positivity in high-grade PCa may lead to misdiagnosis, with clinical implications. We recommend a panel of immunohistochemical markers, both prostatic and urothelial, for ruling out UC, either in primary tumour samples or in the event of metastases of unknown primary, when a genitourinary origin is suspected.
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  • 文章类型: Case Reports
    原发性中枢神经系统(PCNS)结外NK/T细胞淋巴瘤,鼻型(ENKTCL),是一种极为罕见的肿瘤.据我们所知,文献中只有27例和1例报告的异常CD20表达。在这里,我们介绍了第二例PCNSENKTCL,其中CD20表达异常的43岁中国女性。病人出现了震颤,右上肢无力,和一个缓慢的反应。磁共振成像显示多发性脑损伤。组织学检查显示,中等大小的多形性淋巴细胞呈弥散分布,并具有血管中心生长。肿瘤细胞表达CD2,CD3,CD56,T细胞胞内抗原-1,颗粒酶B,和EB病毒编码的RNA(EBER),具有额外的部分和弱CD20和CD30表达。尽管有证实的病理诊断,病人拒绝治疗并出院,最终死于疾病。在文献综述中,临床,免疫组织化学,EBER,治疗,并总结了PCNSENKTCL的预后特征。尽管PCNSENKTCT极为罕见,它确实会发生,并且应始终包括在鉴别诊断中。CD20表达应该用相关标记进行常规评估。病例的积累对于制定针对这种罕见且侵袭性恶性肿瘤的有效治疗策略至关重要。
    Primary central nervous system (PCNS) extranodal NK/T-cell lymphoma, nasal type (ENKTCL), is an exceedingly rare tumor. To the best of our knowledge, only 27 cases and only one reported aberrant CD20 expression have been documented in the literature. Here we present a second case of PCNS ENKTCL with aberrant CD20 expression in a 43-year-old immunocompetent Chinese female. The patient presented with tremors, weakness in the right upper limb, and a slow reaction. Magnetic resonance imaging revealed multiple brain lesions. A histological examination revealed a diffuse distribution of intermediate-sized pleomorphic lymphocytes with angiocentric growth. The tumor cells expressed CD2, CD3, CD56, T-cell intracellular antigen-1, granzyme B, and Epstein-Barr virus-encoded RNAs (EBERs), with additional partial and weak CD20 and CD30 expression. Despite a confirmatory pathological diagnosis, the patient refused treatment and was discharged, ultimately dying from the disease. In the literature review, the clinical, immunohistochemical, EBERs, treatment, and prognostic features of PCNS ENKTCL were summarized. Although PCNS ENKTCT is extremely rare, it does occur and should always be included in differential diagnoses. CD20 expression should be evaluated routinely with relevant markers. The accumulation of cases is crucial for developing an effective treatment strategy for this rare and aggressive malignancy.
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  • 文章类型: Case Reports
    背景:马拉克斑病是一种罕见的泌尿生殖道炎症性疾病。迄今为止,还没有关于表达间变性淋巴瘤激酶(ALK)的malakopakia的报道。这里,我们通过免疫组织化学方法介绍了一例ALK异常表达的ma斑,并讨论了其临床意义。
    方法:一名65岁的中国女性,有糖尿病史,肝脏和肾脏有实体肿块,结肠粘膜表面有升高的病变。行右肾切除术和部分肝切除术。微观上,可见细胞间粘附不良的组织细胞片,胞内和胞外间质中都存在米氏-古特曼体。CD10-,CD68-,和CD163阳性细胞存在,米迦勒-古特曼尸体被阿尔辛蓝染色证实,高碘酸希夫(PAS),高碘酸-希夫与淀粉酶,冯·科萨,还有普鲁士蓝.在细胞的细胞质和细胞核中观察到异常的ALK1和ALK(D5F3)表达。然而,通过荧光原位杂交或全外显子组下一代测序未检测到ALK基因突变。NGS揭示了9个体细胞基因突变:GOT1L1,GLIS2,SPOUT1,TMEM97,MUC3A,NSD2、SFXN5、ADAD1和RAD50。本研究中检测到的体细胞基因突变的意义尚不清楚,现有的科学研究无法阐明它们与马斑病之间的关系。免疫组化病理诊断为真斑病,ALK异常表达。根据药敏分析结果,开始使用亚胺培南和万古霉素抗生素,患者随后出院。在30个月的随访期间,她没有出现不适。
    结论:这是首例ALK异常表达的malakopakia病例,应与ALK阳性组织细胞增生症鉴别,避免误诊。
    BACKGROUND: Malakoplakia is a rare inflammatory disease of the urogenital tract. There have been no reports of malakoplakia expressing anaplastic lymphoma kinase (ALK) to date. Here, we present one case of malakoplakia with aberrant ALK expression by immunohistochemistry and discuss the clinical significance.
    METHODS: A 65-year-old Chinese woman with a history of diabetes presented with solid masses in the liver and kidney and elevated lesions on the mucosal surface of the colon. Right nephrectomy and partial liver resection were performed. Microscopically, sheets of histiocytes with poor intercellular adhesion were seen, with Michaelis-Gutmann bodies present in both the intracellular and extracellular interstitium. CD10-, CD68-, and CD163-positive cells were present, with Michaelis-Gutmann bodies confirmed by staining with Alcian blue, periodic acid-Schiff (PAS), periodic acid-Schiff with diastase, Von Kossa, and Prussian blue. Aberrant ALK1 and ALK (D5F3) expression was observed in the cytoplasm and nucleus of cells. However, ALK gene mutation was not detected by fluorescence in situ hybridization or whole exome next-generation sequencing. NGS revealed nine individual somatic gene mutations: GOT1L1, GLIS2, SPOUT1, TMEM97, MUC3A, NSD2, SFXN5, ADAD1 and RAD50. The significance of the somatic gene mutations detected in this study is not clear, and the relationship between them and malakoplakia cannot be clarified by existing scientific studies. The pathological diagnosis was malakoplakia with aberrant ALK expression by immunohistochemistry. The antibiotics imipenem and vancomycin were started based on the results of drug sensitivity analysis and the patient was subsequently discharged. She experienced no discomfort during 30 months of follow-up.
    CONCLUSIONS: This is the first reported case of malakoplakia with aberrant ALK expression, it should be differentiated from ALK-positive histiocytosis to avoid misdiagnosis.
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  • 文章类型: Journal Article
    紧密连接(TJ)是上皮细胞和内皮细胞中细胞-细胞粘附机制的最顶端成分,它们在稳态中起着至关重要的作用。最近的研究表明,在各种类型的癌症中经常观察到紧密连接蛋白(TJP)的异常表达。在这里,我们回顾了TJPs的癌症相关异常表达,重点是跨膜型TJPs,包括claudins。交界粘附分子-A(JAM-A),和闭塞蛋白。一些跨膜型TJPs在肿瘤早期上调,并且在去分化过程中持续表达。TJPs的异常表达有助于增殖,入侵,和癌细胞的信号失调。除了它们的表达水平增加之外,它们的定位从TJ限制模式改变为分布在整个细胞膜上,使它们适合作为治疗目标。跨膜型TJPs的胞外结构域可以通过靶向药物不仅从管腔侧(顶端侧)而且从细胞外基质侧(基底侧)接近,包括血管.异常表达的TJP是癌症的潜在有用的诊断标志物以及治疗靶标。
    Tight junctions (TJs) are the most apical components of the cell-cell adhesion machinery in epithelial and endothelial cells and they play essential roles in homeostasis. Recent studies have revealed that aberrant expression of tight junction proteins (TJPs) is frequently observed in various type of cancers. Here we review cancer-associated aberrant expression of TJPs with focus on transmembrane-type TJPs including claudins, junctional adhesion molecule-A (JAM-A), and occludin. Some transmembrane-type TJPs are upregulated at the early neoplastic stage and their expression persists during dedifferentiation. Aberrant expression of TJPs contributes to proliferation, invasion, and dysregulated signaling of cancer cells. In addition to an increase in their expression level, their localization is altered from a TJ-restricted pattern to distribution throughout the whole cell membrane, making them suitable as therapeutic targets. Extracellular domains of transmembrane-type TJPs can be approached by target drugs not only from the lumen side (apical side) but also from the extracellular matrix side (basal side), including blood vessels. Aberrantly expressed TJPs are potential useful diagnostic markers as well as therapeutic targets for cancers.
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  • 文章类型: Journal Article
    Paxillin是一种多结构域衔接蛋白。作为局灶性粘连(FA)的重要成员和调节细胞运动的参与者,paxillin在神经系统发育等生理过程中起着重要作用,胚胎发育,和血管发育。然而,越来越多的证据表明,paxillin在许多癌症中异常表达。许多学者也认识到paxillin的异常表达与预后有关,转移,入侵,生存,血管生成,和其他方面的恶性肿瘤,表明paxillin可能是一个潜在的癌症治疗靶点。因此,研究paxillin的异常表达如何影响肿瘤发生和转移过程,将有助于开发更有效的抗肿瘤药物。在这里,我们综述了paxillin的结构及其在肿瘤中的功能和表达,特别关注Paxillin对肿瘤的多方面影响,肿瘤发生和发展的机制,及其在肿瘤治疗中的潜在作用。我们也希望为临床预后和开发新的肿瘤治疗靶点提供参考。
    Paxillin is a multi-domain adaptor protein. As an important member of focal adhesion (FA) and a participant in regulating cell movement, paxillin plays an important role in physiological processes such as nervous system development, embryonic development, and vascular development. However, increasing evidence suggests that paxillin is aberrantly expressed in many cancers. Many scholars have also recognized that the abnormal expression of paxillin is related to the prognosis, metastases, invasion, survival, angiogenesis, and other aspects of malignant tumors, suggesting that paxillin may be a potential cancer therapeutic target. Therefore, the study of how aberrant paxillin expression affects the process of tumorigenesis and metastasis will help to develop more efficacious antitumor drugs. Herein, we review the structure of paxillin and its function and expression in tumors, paying special attention to the multifaceted effects of paxillin on tumors, the mechanism of tumorigenesis and progression, and its potential role in tumor therapy. We also hope to provide a reference for the clinical prognosis and development of new tumor therapeutic targets.
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  • 文章类型: Review
    新出现的证据表明,N6甲基腺苷(m6A)修饰,典型的RNA甲基化修饰,控制修饰转录本的命运,并参与各种人类疾病的发病机理,如代谢紊乱,肾病理学,骨关节炎和恶性肿瘤。长链非编码RNA(lncRNA),长度>200nt的转录本,还表明通过参与表观遗传修饰等过程参与各种疾病,转录交替和翻译后调控。最近的研究表明,lncRNAs被m6A广泛修饰,在与许多疾病相关的各种细胞过程中发挥关键作用,尤其是人类癌症。本综述首先检查了lncRNAs的m6A修饰的功能,包括改变lncRNA结构,介导转录调控,影响mRNA前体剪接,和调节lncRNA稳定性和翻译。此外,总结了m6A修饰的lncRNAs在癌症中的调控机制,并介绍了用于识别lncRNAs上m6A位点的最新检测方法和预测工具。此外,讨论了该领域潜在未来方向的观点,包括更精确的检测方法,lncRNAs编码的微肽在癌症中的作用,m6A修饰的lncRNAs与肿瘤微环境之间的关系,和m6A修饰的lncRNAs作为人类癌症的潜在生物标志物和治疗靶标。
    Emerging evidence has suggested that N6‑methyladenosine (m6A) modification, a typical RNA methylation modification, controls the fate of modified transcripts and is involved in the pathogenesis of various human diseases, such as metabolic disorders, nephropathology, osteoarthritis and malignant tumours. Long noncoding RNAs (lncRNAs), transcripts of >200 nt in length, have also been indicated to be involved in various diseases by participating in processes such as epigenetic modifications, transcriptional alternations and posttranslational regulation. Recent studies revealed that lncRNAs were widely modified by m6A, which has a critical role in various cellular processes that are associated with numerous disorders, particularly human cancers. The present review first examined functions of m6A modification of lncRNAs, including changing the lncRNA structure, mediating transcriptional regulation, affecting mRNA precursor splicing, and regulating lncRNA stability and translation. Furthermore, the regulatory mechanisms of m6A‑modified lncRNAs in cancers were summarized and the up‑to‑date detection methods and prediction tools for identifying m6A sites on lncRNAs were presented. In addition, viewpoints on potential future directions in the field were discussed, including more accurate detection methods, roles of lncRNAs‑encoded micropeptides in cancers, the relationship between m6A‑modified lncRNAs and the tumour microenvironment, and m6A‑modified lncRNAs as potential biomarkers and therapeutic targets in human cancer.
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