SOX6 represses tumor growth of clear cell renal cell carcinoma by HMG domain-dependent regulation of Wnt/β-catenin signaling

Sex-determining region Y box (SOXs) are expressed in various cells and control cell fate and differentiation in a multitude of physiologic processes. SOX6, a main representative of SOXs, is involved in the regulation of carcinogenesis in various human malignancies. However, the role of SOX6 in clear cell renal cell carcinoma (ccRCC) remains unclear. In this study, SOX6 expression in ccRCC and its clinical significance were investigated. In vitro and in vivo assays were used to explore the tumor-related function and the underlying molecular mechanism of SOX6 in ccRCC. We confirmed that SOX6 was frequently downregulated in ccRCC tissues and cell lines. Besides, downregulation of SOX6 was significantly associated with larger tumor sizes, advanced tumor stage, higher Fuhrman grades, and its expression could act as an independent prognostic factor for ccRCC (hazards ratio = 0.590, P = .026). Gain/loss-of-function experiments demonstrated that SOX6 could remarkably inhibit tumor cell growth and foci formation in vitro and xenograft tumorigenesis in vivo, respectively. Mechanistically, SOX6 could influence cell cycle by regulating the G1/the S phase transition and had an inhibitory effect on Wnt/β-catenin signaling as well as its target genes, c-Myc and cyclin D1. Interesting, the tumor-suppressive function of SOX6 was proved to be dependent on its specific high-mobility-group (HMG) domain. In general, our findings indicated that SOX6 was a novel tumor suppressor and prognostic biomarker in ccRCC. SOX6 could inhibit tumor growth by negatively regulating the Wnt/β-catenin signaling pathway in an HMG domain-dependent manner in ccRCC, which might provide a novel therapeutic approach for ccRCC.     

Notch1 contributes to TNF-α-induced proliferation and migration of airway smooth muscle cells through regulation of the Hes1/PTEN axis

Notch1 has been implicated in asthma pathogenesis. However, the function of Notch1 in regulating airway smooth muscle (ASM) cell proliferation and migration during airway remodeling of asthma remains unknown. Using an in vitro model induced by tumor necrosis factor (TNF)-α, we reported in this study that Notch1 participated in TNF-α-induced proliferation and migration of ASM cells. Our results demonstrated that Notch1 expression was significantly upregulated in ASM cells exposed to TNF-α. Notch1 inhibition significantly repressed TNF-α-induced ASM cell proliferation and migration, while Notch1 overexpression promoted the opposite effect. Moreover, Notch1 inhibition downregulated the expression of Notch-1 intracellular domain (NICD) and Hes1, while upregulated PTEN expression in TNF-α-exposed cells. Notably, Hes1 overexpression partially reversed the Notch1-inhibition-mediated inhibitory effect on TNF-α-induced ASM cell proliferation and migration. In addition, the promoting effect of Notch1 inhibition on PTEN expression was markedly abrogated by Hes1 overexpression. Overall, these findings demonstrated that Notch1 inhibition repressed TNF-α-induced ASM cell proliferation and migration by modulating the Hes1/PTEN signaling axis, a finding that highlights the involvement of Notch1/Hes1/PTEN in regulating airway remodeling of asthma.     

沉默己糖激酶结构域蛋白1表达对胃癌细胞增殖、侵袭、转移和上皮间充质转化的影响

目的探讨己糖激酶结构域蛋白1(HKDC1)成为胃癌潜在治疗靶点的可能性。方法用脂质体法向胃癌细胞NCI-N87,BGC-823和HGC-27转染沉默HKDC1表达的小干扰RNA(siRNA)(siRNA-1和siRNA-2),同时设阴性对照siRNA(siRNA-NC)组,分别获得NCI-N87-siRNA-NC,NCI-N87-siRNA-1和NCI-N87-siRNA-2细胞,BGC-823-siRNA-NC,BGC-823-siRNA-1和BGC-823-siRNA-2细胞,HGC-27-siRNA-NC,HGC-27-siRNA-1和HGC-27-siRNA-2细胞,用Western印迹法检测siRNA对HKDC1表达的抑制效果,并计算抑制率。将上述细胞接种入96孔板,孵育72 h后,磺酰罗丹明B(SRB)染色法检测细胞存活,计算细胞存活率。将上述细胞分别接种入无基质胶和铺有基质胶的Transwell小室,24 h后计数小室下室细胞数,分别检测细胞迁移和侵袭能力。收集上述细胞提取蛋白质,用Western印迹法检测上皮间充质转化相关蛋白E-钙黏蛋白、N-钙黏蛋白和Snail的表达。结果分别转染siRNA-1和siRNA-2,对NCIN87-siRNA-1和NCI-N87-siRNA-2细胞HKDC1表达的抑制率分别为(20.5±0.1)%和(48.6±0.1)%,对BGC-823-siRNA-1和BGC-823-siRNA-2细胞的抑制率分别为(56.5±0.1)%和(58.9±0.1)%,对HGC-27-siRNA-1和HGC-27-siRNA-2细胞的抑制率分别为(63.5±0.1)%和(85.9±0.1)%。与对应的阴性对照组细胞相比,NCI-N87-siRNA-1和NCI-N87-siRNA-2细胞的存活率分别为(68.2±2.5)%和(70.4±2.1)%(P<0.01),BGC-823-siRNA-1和BGC-823-siRNA-2细胞的存活率分别为(77.0±0.1)%和(73.7±0.1)%(P<0.05),HGC-27-siRNA-1和HGC-27-siRNA-2细胞的存活率分别为(63.2±0.6)%和(70.4±0.1)%(P<0.01,P<0.05)。NCI-N87-siRNA-NC,NCI-N87-siRNA-1和NCI-N87-siRNA-2细胞的迁移数分别为488±43,319±27和262±37(P<0.01),侵袭数分别为143±8,68±2和30±2(P<0.01);BGC-823-siRNA-NC,BGC-823-siRNA-1和BGC-823-siRNA-2细胞的迁移数分别为1131±69,830±159和579±57(P<0.01),侵袭数分别为1127±113,781±97和565±96(P<0.01);HGC-27-siRNA-NC,HGC-27-siRNA-1和HGC-27-siRNA-2细胞的迁移数分别为453±36,190±25和57±16(P<0.01),侵袭数分别为645±53,462±62和264±47(P<0.01)。与对应阴性对照组相比,3种细胞HKDC1 siRNA-1和HKDC1 siRNA-2组细胞内E-钙黏蛋白的表达显著升高(P<0.05),N-钙黏蛋白和Snail的表达显著下降(P<0.05)。结论沉默HKDC1表达可抑制胃癌细胞增殖、侵袭和转移,并抑制上皮间充质转化。     

A Hodge Decomposition Method for Dynamic Ginzburg–Landau Equations in Nonsmooth Domains — A Second Approach

In a general polygonal domain, possibly nonconvex and multi-connected (with holes), the time-dependent Ginzburg–Landau equation is reformulated into a new system of equations. The magnetic field $B$:=∇×A is introduced as an unknown solution in the new system, while the magnetic potential A is solved implicitly through its Hodge decomposition into divergence-free part, curl-free and harmonic parts, separately. Global well-posedness of the new system and its equivalence to the original problem are proved. A linearized and decoupled Galerkin finite element method is proposed for solving the new system. The convergence of numerical solutions is proved based on a compactness argument by utilizing the maximal $L^p$-regularity of the discretized equations. Compared with the Hodge decomposition method proposed in [27]_,the new method has the advantage of approximating the magnetic field B directly and converging for initial conditions that are incompatible with the external magnetic field. Several numerical examples are provided to illustrate the efficiency of the proposed numerical method in both simply connected and multi-connected nonsmooth domains. We observe that even in simply connected domains, the new method is superior to the method in [27] for approximating the magnetic field.     

Effective Two-Level Domain Decomposition Preconditioners for Elastic Crack Problems Modeled by Extended Finite Element Method

In this paper, we propose some effective one- and two-level domain decomposition preconditioners for elastic crack problems modeled by extended finite element method. To construct the preconditioners, the physical domain is decomposed into the "crack tip" subdomain, which contains all the degrees of freedom (dofs) of the branch enrichment functions, and the "regular" subdomains, which contain the standard dofs and the dofs of the Heaviside enrichment function. In the one-level additive Schwarz and restricted additive Schwarz preconditioners, the "crack tip" subproblem is solved directly and the "regular" subproblems are solved by some inexact solvers, such as ILU. In the two-level domain decomposition preconditioners, traditional interpolations between the coarse and the fine meshes destroy the good convergence property. Therefore, we propose an unconventional approach in which the coarse mesh is exactly the same as the fine mesh along the crack line, and adopt the technique of a non-matching grid interpolation between the fine and the coarse meshes. Numerical experiments demonstrate the effectiveness of the two-level domain decomposition preconditioners applied to elastic crack problems.     

HBeAg阳性慢性乙型肝炎患者HBV前C/BCP突变/准种与HBeAg和HBV DNA的关系

目的探讨HBeAg阳性慢性乙型肝炎（eP-CHB）HBV前C/BCP突变/准种及其与HBeAg、HBV DNA水平的关系。 方法采用断面研究对2016年1月至2018年12月就诊于首都医科大学附属北京佑安医院的220例eP-CHB患者进行前C/BCP突变检测，其中24例患者进行前C/BCP区扩增、克隆，同步检测血清HBeAg和HBV DNA水平，分析前C/BCP突变/准种的发生情况及其与HBeAg和HBV DNA水平的关系。 结果220例eP-CHB患者中，HBV前C/BCP总突变率为70.0%（154/220），前C/BCP共同突变率为18.2%（40/220），前C突变率为30.9%（68/220），BCP突变率为57.3%（126/220）。HBV DNA≥ 5 lgIU/ml患者上述4种突变检出率均高于HBV DNA< 5 lgIU/ml者，其中前C/BCP总突变和BCP突变患者差异有统计学意义（χ² = 5.809、P = 0.016，χ² = 5.081、P = 0.024）。HBeAg水平越低（< 500 COI、500～1 000 COI和> 1 000 COI共3组患者比较），以上4种突变检出率越高，差异有统计学意义（χ² = 31.738、17.291、16.263、22.164，P均< 0.001）。HBV DNA≥ 5 lgIU/ml患者中，HBeAg水平越低，以上4种突变检出率越高，差异亦均有统计学意义（χ² = 40.503、19.654、16.727、29.119，P < 0.001）。准种检测中，前C区高突变组患者HBeAg水平低于低突变组，差异有统计学意义（t = 2.230、P = 0.017），前C、BCP高突变组与低突变组间HBV DNA水平差异无统计学意义（t = 0.624、P = 0.462，t = 0.893、P = 0.317）。 结论eP-CHB患者中仍存在广泛的前C/BCP突变。高HBV DNA、低HBeAg表达者，前C和BCP突变的发生率较高；前C区突变株在准种中比率高者更影响HBeAg的表达。推测前C/BCP突变可能是eP-CHB出现低HBeAg、高HBV DNA，并导致抗病毒治疗停药后易复发的原因。     

Membrane-associated mucins of the ocular surface: New genes,new protein functions and new biological roles in human and mouse

The mucosal glycocalyx of the ocular surface constitutes the point of interaction between the tear film and the apical epithelial cells. Membrane-associated mucins (MAMs) are the defining molecules of the glycocalyx in all mucosal epithelia. Long recognized for their biophysical properties of hydration, lubrication, anti-adhesion and repulsion, MAMs maintain the wet ocular surface, lubricate the blink, stabilize the tear film and create a physical barrier to the outside world. However, it is increasingly appreciated that MAMs also function as cell surface receptors that transduce information from the outside to the inside of the cell. A number of excellent review articles have provided perspective on the field as it has progressed since 1987, when molecular cloning of the first MAM was reported. The current article provides an update for the ocular surface, placing it into the broad context of findings made in other organ systems, and including new genes, new protein functions and new biological roles. We discuss the epithelial tissue-equivalent with mucosal differentiation, the key model system making these advances possible. In addition, we make the first systematic comparison of MAMs in human and mouse, establishing the basis for using knockout mice for investigations with the complexity of an in vivo system. Lastly, we discuss findings from human genetics/genomics, which are providing clues to new MAM roles previously unimagined. Taken together, this information allows us to generate hypotheses for the next stage of investigation to expand our knowledge of MAM function in intracellular signaling and roles unique to the ocular surface.