Stroma

基质
  • 文章类型: Journal Article
    最近,广泛的良性和恶性原发性间充质肿瘤和脾脏肿瘤样病变被纳入“基质衍生的肿瘤和肿瘤样病变”这一术语。这些包括树突细胞肿瘤,如滤泡树突细胞肉瘤,EBV阳性炎性滤泡树突状细胞肉瘤,和纤维母细胞网状细胞肿瘤;平滑肌和肌纤维母细胞病变,如炎性假瘤,EBV相关的平滑肌肿瘤和未分化的多形性肉瘤以及多种血管和血管间质肿瘤和肿瘤样病变。虽然有些肿瘤和肿瘤样病变是脾脏特有的,其他也可能发生在不同的脾外内脏。这些肿瘤和肿瘤样病变表现出特征性的组织病理学,免疫细胞化学和生物学行为。虽然横断面成像研究允许检测,这些脾病变的分期和有限的特征,组织病理学确认允许最佳管理和监测策略。
    A wide spectrum of benign and malignant primary mesenchymal tumors and tumor-like lesions of the spleen has been recently included under the umbrella term \'stroma-derived\' neoplasms and tumor-like lesions. These include dendritic cell neoplasms such as follicular dendritic cell sarcoma, EBV-positive inflammatory follicular dendritic cell sarcoma, and fibroblastic reticular cell tumor; smooth muscle and myofibroblastic lesions such as inflammatory pseudotumor, EBV-associated smooth muscle tumor and undifferentiated pleomorphic sarcoma as well as a diverse spectrum of vascular and vascular-stromal tumors and tumor-like lesions. While some tumor and tumor-like lesions are unique to the spleen, others may also occur in diverse extra-splenic viscera. These tumors and tumor-like lesions demonstrate characteristic histopathology, immunocytochemistry and biological behavior. While cross-sectional imaging studies allow detection, staging and limited characterization of these splenic lesions, histopathological confirmation permits optimal management and surveillance strategies.
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  • 文章类型: Journal Article
    目的:评估三种新型生物标志物的预后价值,DNA倍性,间质肿瘤分数,和核型分析,在II期结肠癌中寻求更准确的分层。
    方法:本研究共纳入417例具有完整随访信息的患者,并将其分为三个临床风险组。进行IHC检查MSI状态。DNA倍性,使用自动数字成像系统估计基质和核型。Kaplan-Meier存活曲线,Cox比例风险回归模型,并进行相关分析以处理我们的数据。
    结果:在整个II期结肠癌队列中,在单变量分析中,核型和DNA倍体是OS的重要预后因素。核型和DNA倍性的结合表明了优越的OS和DFS。低基质和高基质患者之间的差异不显着。在多变量分析中,证明核型以及核型和DNA倍性的组合是OS的主要促成因素。在低风险组中,我们发现,在单变量和多变量中,核型和DNA倍体的组合作为独立的预后因素具有统计学意义,而在高危人群中,核型。
    结论:我们的研究已证明核型以及DNA倍性和核型的组合是独立的预后指标,从而将核型分析作为预测因子的应用从高风险II期结肠癌扩展到整体风险.
    OBJECTIVE: To assess the prognostic value of three novel biomarkers, DNA ploidy, stroma-tumor fraction, and nucleotyping, seeking for more accurate stratification in stage II colon cancer.
    METHODS: A total of 417 patients with complete follow up information were enrolled in this study and divided into three clinical risk groups. IHC was performed to examine MSI status. DNA ploidy, stroma and nucleotyping were estimated using automated digital imaging system. Kaplan-Meier survival curves, Cox proportional hazards regression models, and correlation analyses were carried out to process our data.
    RESULTS: In the whole cohort of stage II colon cancer, nucleotyping and DNA ploidy were significant prognostic factors on OS in univariate analyses. The combination of nucleotyping and DNA ploidy signified superior OS and DFS. Difference was not significant between low-stroma and high-stroma patients. In multivariable analyses, nucleotyping and the combination of nucleotyping and DNA ploidy were proven the dominant contributory factors for OS. In the low-risk group, we found the combination of nucleotyping and DNA ploidy as the independent prognostic factor statistically significant in both univariate and multivariable, while in the high-risk group, the nucleotyping.
    CONCLUSIONS: Our study has proven nucleotyping and the combination of DNA ploidy and nucleotyping as independent prognostic indicators, thus expanding the application of nucleotyping as a predictor from high risk stage II colon cancer to whole risks.
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  • 文章类型: Journal Article
    本文通过将口腔器官呈现为整个生物体及其周围环境中的一个整体,为口腔生理学带来了新的视角。而不是将嘴仅仅视为离散函数的集合,这种新颖的方法强调了它作为动态界面的作用,支持身体和外部因素之间的相互作用。作为一个有弹性的生态系统,口腔生态位的平衡是大量相互关联的因素的结果,包括不同口腔结构的异质性,资源的多样性,外部和内部压力以及生物行为者。该手稿旨在加深对口腔内和整个生物体内与年龄相关的变化的理解,与不断发展的老年病学领域保持一致。嘴的战略地位和根本功能使其成为早期预防的宝贵目标,诊断,治疗,甚至逆转整个生物体的衰老效应。认识到口腔的感官知觉能力,元素捕获和信息处理强调了其在持续健康监测中的重要作用。总的来说,这种对口腔生理学的综合理解旨在推进口腔保健的综合方法,并促进更广泛地认识口腔保健对整体福祉的影响。
    This article brings a new perspective on oral physiology by presenting the oral organ as an integrated entity within the entire organism and its surrounding environment. Rather than considering the mouth solely as a collection of discrete functions, this novel approach emphasizes its role as a dynamic interphase, supporting interactions between the body and external factors. As a resilient ecosystem, the equilibrium of mouth ecological niches is the result of a large number of interconnected factors including the heterogeneity of different oral structures, diversity of resources, external and internal pressures and biological actors. The manuscript seeks to deepen the understanding of age-related changes within the oral cavity and throughout the organism, aligning with the evolving field of gerophysiology. The strategic position and fundamental function of the mouth make it an invaluable target for early prevention, diagnosis, treatment, and even reversal of aging effects throughout the entire organism. Recognizing the oral cavity capacity for sensory perception, element capture and information processing underscores its vital role in continuous health monitoring. Overall, this integrated understanding of the oral physiology aims at advancing comprehensive approaches to the oral healthcare and promoting broader awareness of its implications on the overall well-being.
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  • 文章类型: Journal Article
    神经纤维蛋白,由NF1肿瘤抑制基因编码,是RAS途径的主要负调节因子,在各种癌症中经常发生突变。患有I型神经纤维瘤病(NF1)的女性-由种系NF1突变引起的肿瘤易感性综合征-患侵袭性乳腺癌的风险增加,预后较差。NF1突变导致乳腺癌肿瘤发生的机制尚不清楚。因此,这项工作的目的是确定肿瘤形成前的间质改变,这些改变导致NF1乳腺癌患者的风险增加和预后较差.
    为了准确模拟NF1患者的种系单等位基因NF1突变,在出现高渗透性乳腺癌之前,我们使用了Nf1缺陷大鼠模型,该模型具有加速的乳腺发育。
    我们发现,在肿瘤形成之前,Nf1缺陷的大鼠乳腺中胶原蛋白含量增加,这与肿瘤发病年龄有关。此外,基因表达分析显示,大鼠乳腺中缺乏Nf1的成熟脂肪细胞的胶原蛋白表达增加,并转变为成纤维细胞和前脂肪细胞表达谱。在体外分化中也观察到谱系定型的这种改变,然而,流式细胞术分析未显示乳腺脂肪间充质干细胞丰度的变化.
    集体,这项研究揭示了以前未描述的Nf1在乳腺胶原沉积和调节脂肪细胞分化中的作用。除了揭示肿瘤形成的机制,进一步研究肿瘤前乳腺中的脂肪细胞和胶原修饰将为制定NF1患者乳腺癌的早期检测策略奠定基础.
    UNASSIGNED: Neurofibromin, coded by the NF1 tumor suppressor gene, is the main negative regulator of the RAS pathway and is frequently mutated in various cancers. Women with Neurofibromatosis Type I (NF1)-a tumor predisposition syndrome caused by a germline NF1 mutation-have an increased risk of developing aggressive breast cancer with poorer prognosis. The mechanism by which NF1 mutations lead to breast cancer tumorigenesis is not well understood. Therefore, the objective of this work was to identify stromal alterations before tumor formation that result in the increased risk and poorer outcome seen among NF1 patients with breast cancer.
    UNASSIGNED: To accurately model the germline monoallelic NF1 mutations in NF1 patients, we utilized an Nf1-deficient rat model with accelerated mammary development before presenting with highly penetrant breast cancer.
    UNASSIGNED: We identified increased collagen content in Nf1-deficient rat mammary glands before tumor formation that correlated with age of tumor onset. Additionally, gene expression analysis revealed that Nf1-deficient mature adipocytes in the rat mammary gland have increased collagen expression and shifted to a fibroblast and preadipocyte expression profile. This alteration in lineage commitment was also observed with in vitro differentiation, however, flow cytometry analysis did not show a change in mammary adipose-derived mesenchymal stem cell abundance.
    UNASSIGNED: Collectively, this study uncovered the previously undescribed role of Nf1 in mammary collagen deposition and regulating adipocyte differentiation. In addition to unraveling the mechanism of tumor formation, further investigation of adipocytes and collagen modifications in preneoplastic mammary glands will create a foundation for developing early detection strategies of breast cancer among NF1 patients.
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  • 文章类型: Journal Article
    角膜是细胞治疗的理想测试领域。其高度有序的结构,特定的细胞群体被隔离在不同的层中,连同它的可访问性,已经允许开发第一个由欧洲医学机构批准的基于干细胞的疗法。今天,已经提出了不同的技术用于自体和同种异体角膜缘和非角膜缘细胞移植。在Fuchs营养不良中发生的内皮细胞代偿失调的情况下,也尝试了细胞置换:注射培养的同种异体内皮细胞现在处于临床发展的晚期。最近,已经开发出具有出色集成能力和透明度的基质替代品。最后,细胞衍生产品,例如从不同来源获得的外泌体,已对严重角膜疾病的治疗进行了研究,并取得了令人鼓舞的结果。细胞治疗成功率的优化显然需要高质量的培养细胞/产品,但是周围微环境的作用对于移植细胞的植入同样重要,为了维护他们的功能,最终,导致角膜组织完整性和透明度的恢复。
    The cornea is an ideal testing field for cell therapies. Its highly ordered structure, where specific cell populations are sequestered in different layers, together with its accessibility, has allowed the development of the first stem cell-based therapy approved by the European Medicine Agency. Today, different techniques have been proposed for autologous and allogeneic limbal and non-limbal cell transplantation. Cell replacement has also been attempted in cases of endothelial cell decompensation as it occurs in Fuchs dystrophy: injection of cultivated allogeneic endothelial cells is now in advanced phases of clinical development. Recently, stromal substitutes have been developed with excellent integration capability and transparency. Finally, cell-derived products, such as exosomes obtained from different sources, have been investigated for the treatment of severe corneal diseases with encouraging results. Optimization of the success rate of cell therapies obviously requires high-quality cultured cells/products, but the role of the surrounding microenvironment is equally important to allow engraftment of transplanted cells, to preserve their functions and, ultimately, lead to restoration of tissue integrity and transparency of the cornea.
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  • 文章类型: Journal Article
    自从纳米医学出现以来,医生已经利用这些方法进行预防,检测,和治疗危及生命的疾病,尤其是癌症。纳米颗粒在癌症治疗中表现出显著的疗效,展示纳米技术在靶向药物递送中的主要应用。胰腺癌是人类中最致命的实体瘤。低存活率归因于其高度侵略性,对化学疗法的内在抗性,缺乏成功的治疗方法,由于非特异性症状和缺乏快速诊断策略而导致诊断延迟。尽管面临这些挑战,基于纳米技术的载体方法已成功用于成像和治疗方法。克服胰腺癌的耐药性需要全面了解与该疾病相关的微环境,为创新纳米载体铺平道路。化疗浸润受阻,归因于血管形成不足和致密的肿瘤基质,是纳米技术解决的一个主要障碍。智能交付技术,基于增强的渗透性和保留效应,形成最近开发的抗癌纳米载体的基础。这些进步旨在增强药物在肿瘤部位的积累,为癌症的治疗抗性提供了一个潜在的解决方案。应对胰腺癌治疗的挑战需要创新的疗法,活性纳米载体的出现为增强成果提供了有希望的途径。这篇综述专门探讨了纳米技术在胰腺癌治疗中的最新进展。
    Since the advent of nanomedicine, physicians have harnessed these approaches for the prophylaxis, detection, and therapy of life-threatening diseases, particularly cancer. Nanoparticles have demonstrated notable efficacy in cancer therapy, showcasing the primary application of nanotechnology in targeted drug delivery. Pancreatic cancer stands out as the most lethal solid tumour in humans. The low survival rate is attributed to its highly aggressive nature, intrinsic resistance to chemotherapeutics, and the lack of successful therapies, compounded by delayed diagnosis due to nonspecific symptoms and the absence of rapid diagnostic strategies. Despite these challenges, nanotechnology-based carrier methods have been successfully employed in imaging and therapy approaches. Overcoming drug resistance in pancreatic cancer necessitates a comprehensive understanding of the microenvironment associated with the disease, paving the way for innovative nanocarriers. Hindered chemotherapy infiltration, attributed to inadequate vascularization and a dense tumour stroma, is a major hurdle that nanotechnology addresses. Intelligent delivery techniques, based on the Enhanced Permeability and Retention effect, form the basis of recently developed anticancer nanocarriers. These advancements aim to enhance drug accumulation in tumour locations, offering a potential solution to the treatment-resistant nature of cancer. Addressing the challenges in pancreatic cancer treatment demands innovative therapies, and the emergence of active nanocarriers presents a promising avenue for enhancing outcomes. This review specifically delves into the latest advancements in nanotechnology for the treatment of pancreatic cancer.
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  • 文章类型: Journal Article
    细胞外基质(ECM)由复杂的纤维状蛋白组成,蛋白聚糖,和大分子,由基质产生,免疫,和癌细胞。基质的成分和组织随着肿瘤发展为侵袭性疾病和转移而演变。在许多实体瘤中,已经假设致密性纤维化ECM通过限制药物和免疫细胞的进入来阻碍治疗反应。针对ECM各个组件的干预措施,统称为婚姻,有,然而,揭示了复杂的肿瘤抑制剂,肿瘤启动子,和免疫调节功能,复杂的临床翻译。基质组的不同成分可以决定肿瘤表型和对治疗的反应的程度是深入研究的主题。一个主要目的是在母系中确定治疗机会,这可能支持对现有疗法的更好反应。已经开发了许多可以预测预后的矩阵特征,免疫细胞含量,和免疫疗法反应。在这次审查中,我们将检查与晚期肿瘤和治疗抵抗相关的关键组元。我们在这里主要关注的是针对母系成分,而不是特定的细胞类型,尽管描述了几个例子,其中起源细胞可以显着影响基质成分的肿瘤作用。当我们解开复杂的生化时,生物物理,和与ECM相关的细胞内转导机制,将确定许多治疗机会来改变肿瘤进展和治疗反应。
    The extracellular matrix (ECM) is composed of complex fibrillar proteins, proteoglycans, and macromolecules, generated by stromal, immune, and cancer cells. The components and organisation of the matrix evolves as tumours progress to invasive disease and metastasis. In many solid tumours, dense fibrotic ECM has been hypothesised to impede therapy response by limiting drug and immune cell access. Interventions to target individual components of the ECM, collectively termed the matrisome, have, however, revealed complex tumour-suppressor, tumour-promoter, and immune-modulatory functions, which have complicated clinical translation. The degree to which distinct components of the matrisome can dictate tumour phenotypes and response to therapy is the subject of intense study. A primary aim is to identify therapeutic opportunities within the matrisome, which might support a better response to existing therapies. Many matrix signatures have been developed which can predict prognosis, immune cell content, and immunotherapy responses. In this review, we will examine key components of the matrisome which have been associated with advanced tumours and therapy resistance. We have primarily focussed here on targeting matrisome components, rather than specific cell types, although several examples are described where cells of origin can dramatically affect tumour roles for matrix components. As we unravel the complex biochemical, biophysical, and intracellular transduction mechanisms associated with the ECM, numerous therapeutic opportunities will be identified to modify tumour progression and therapy response.
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  • 文章类型: Journal Article
    耐药性是有效癌症治疗的主要问题,基质构成了肿瘤块的重要部分,但传统的药物筛选仅涉及癌细胞。癌相关成纤维细胞(CAFs)是肿瘤基质的主要成分,其分泌蛋白可能影响癌细胞的功能。大多数分泌组研究仅比较不同的癌症或CAF细胞系。这里,我们提供了来自结直肠的CAFs和KRAS突变癌细胞系之间的分泌蛋白谱的直接表征,肺,和使用多重质谱的胰腺组织。2573个分泌蛋白被注释,差异分析强调了未研究的富含CAF的分泌蛋白,包括Wnt家族成员5B(WNT5B),除了已建立的CAF标记,如胶原蛋白。通过评估CAF分泌蛋白对97种抗癌药物反应的影响来探索CAF分泌蛋白的功能作用,因为基质细胞可能会引起不同的癌症药物反应。在单独使用癌细胞的常规药物筛查中可能会遗漏。CAF分泌蛋白对每个癌细胞系产生特定的影响,这突出了癌症治疗的复杂性和挑战,以及考虑基质元素的重要性。
    Resistance is a major problem with effective cancer treatment and the stroma forms a significant portion of the tumor mass but traditional drug screens involve cancer cells alone. Cancer-associated fibroblasts (CAFs) are a major tumor stroma component and its secreted proteins may influence the function of cancer cells. The majority of secretome studies compare different cancer or CAF cell lines exclusively. Here, we present the direct characterization of the secreted protein profiles between CAFs and KRAS mutant-cancer cell lines from colorectal, lung, and pancreatic tissues using multiplexed mass spectrometry. 2573 secreted proteins were annotated, and differential analysis highlighted understudied CAF-enriched secreted proteins, including Wnt family member 5B (WNT5B), in addition to established CAF markers, such as collagens. The functional role of CAF secreted proteins was explored by assessing its effect on the response to 97 anticancer drugs since stromal cells may cause a differing cancer drug response, which may be missed on routine drug screening using cancer cells alone. CAF secreted proteins caused specific effects on each of the cancer cell lines, which highlights the complexity and challenges in cancer treatment and so the importance to consider stromal elements.
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  • 文章类型: Journal Article
    肿瘤微环境(TME)给细胞带来了挑战,例如pH值可变,缺氧,和自由基,触发影响癌症进展的应激反应。在这项研究中,我们检查了四种乳腺癌的应激反应情况,胰腺,子房,和前列腺-跨越五种途径:热休克,氧化应激,缺氧,DNA损伤,和展开的蛋白质压力。采用实验和计算相结合的方法,我们创建了一个跨不同类型癌症的应激反应图集。我们发现应激反应在TME内变化,并且在癌细胞附近特别活跃。专注于我们发现的非免疫基质,跨肿瘤类型,NRF2和氧化应激反应在免疫调节性癌症相关成纤维细胞和独特的癌症相关周细胞亚群中明显激活。因此,我们的研究提供了癌症中应激反应的相互作用组,提供了在肿瘤内交叉生存途径的方法,推进癌症治疗。
    The tumor microenvironment (TME) presents cells with challenges such as variable pH, hypoxia, and free radicals, triggering stress responses that affect cancer progression. In this study, we examine the stress response landscape in four carcinomas-breast, pancreas, ovary, and prostate-across five pathways: heat shock, oxidative stress, hypoxia, DNA damage, and unfolded protein stress. Using a combination of experimental and computational methods, we create an atlas of stress responses across various types of carcinomas. We find that stress responses vary within the TME and are especially active near cancer cells. Focusing on the non-immune stroma we find, across tumor types, that NRF2 and the oxidative stress response are distinctly activated in immune-regulatory cancer-associated fibroblasts and in a unique subset of cancer-associated pericytes. Our study thus provides an interactome of stress responses in cancer, offering ways to intersect survival pathways within the tumor, and advance cancer therapy.
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  • 文章类型: Journal Article
    背景:胰腺导管腺癌(PDAC)对抗肿瘤药物的反应较差。化合物的临床前成功和临床失败之间的差异一直是PDAC研究中的持续挑战和主要障碍。
    目的:研究肿瘤微环境(TME)组成与吉西他滨代谢酶(GME)表达的关系。
    方法:GME的mRNA表达和蛋白质水平(胞质5'-核苷酸酶1A;NT5C1A,胞苷脱氨酶;CDA,脱氧胞苷激酶;DCK),吉西他滨转运体(ENT1,ENT2,RRM1,RRM2)和基质成分(透明质酸,podoplanin,马森三色,picrosirius)通过qRT-PCR和免疫组织化学在鼠LSL-KrasG12D/+中进行评估;LSL-Trp53R172H/+;Pdx-1-Cre(KPC),原位移植小鼠(OTM),人原发性切除的PDAC组织(hPRT),相应的患者源性异种移植(PDX)小鼠,和KPC-SPARC-/-小鼠。在PDAC细胞系中分析GME的mRNA表达(Panc-1,MIAPaCa,BXPC3和L3.6)通过qRT-PCR在胶原蛋白或胰腺星状细胞(PSC)条件培养基上孵育后。
    结果:与OTM相比,内源性KPC肿瘤表现出明显更高的GME水平。然而,GME水平在hPRT和相应的PDX小鼠之间没有差异。使用KendallsTau相关系数,除了PDX小鼠中的NT5C1A和透明质酸之外,我们没有显示GME与TME成分的显着相关性(p=0.029)。GME在体内SPARC耗竭后没有显著改变,并且在用PSC条件培养基处理或在体外胶原铺板培养皿上孵育后。
    结论:我们的发现表明GME的表达与基质成分的沉积无关。KPC小鼠最适于研究基质组成,而PDX小鼠维持相应hPRT的GME表达,并且可能最适于药代动力学研究。
    Pancreatic ductal adenocarcinoma (PDAC) poorly responds to antineoplastic agents. Discrepancies between preclinical success and clinical failure of compounds has been a continuous challenge and major obstacle in PDAC research.
    To investigate the association of the tumor microenvironment (TME) composition and gemcitabine metabolizing enzyme (GME) expression in vitro and several in vivo models.
    mRNA expression and protein levels of GME (cytosolic 5\'-nucleotidase 1 A; NT5C1A, cytidine deaminase; CDA, deoxycytidine kinase; DCK), gemcitabine transporters (ENT1, ENT2, RRM1, RRM2) and stromal components (hyaluroninc acid, podoplanin, masson trichrome, picrosirius) were assessed by qRT-PCR and immunohistochemistry in murine LSL-KrasG12D/+;LSL-Trp53R172 H/+; Pdx-1-Cre (KPC), orthotopically transplanted mice (OTM), human primary resected PDAC tissue (hPRT), corresponding patient-derived xenograft (PDX) mice, and KPC-SPARC-/- mice. mRNA expression of GME was analyzed in PDAC cell lines (Panc-1, MIA PaCa, BXPC3 and L3.6) upon incubation on collagen or pancreatic stellate cell (PSC) conditioned media by qRT-PCR.
    Endogenous KPC tumors exhibited significantly higher levels of GME compared to OTM. However, GME levels did not differ between hPRT and corresponding PDX mice. Using Kendalls Tau correlation coefficient we did not show a significant correlation of GME and components of the TME except for NT5C1A and hyaluronic acid in PDX mice (p=0.029). GME were not significantly altered upon SPARC depletion in vivo, and upon treatment with PSC-conditioned media or incubation on collagen plated dishes in vitro.
    Our findings suggest that the expression of GME is independent from the deposition of stromal components. KPC mice are most appropriate to study stromal composition whereas PDX mice maintain GME expression of the corresponding hPRT and could be best suited for pharmacokinetic studies.
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