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Boat is mainly composed of hull, ship frame, deck, cabin and ship deck building. When people are designing the boat, one key consideration is the shape of the bow in order to decrease the resistance and fuel-consumption. In this paper, theoretical analysis of resistance to bow and the optimization aimed for lower resistance were produced by using COMSOL Multiphysics 6.0. Firstly, a simple and ordinary model of bow is presented. Then, the mathematical and physical model are established by COMSOL. Afterwards, after I exam whether the computational model is effective enough for the further optimization, the calculating results are worked out and I compare them with the common bow’s experimental data, with the purpose of the optimization, the lower resistance, in different conditions such as different ship speed and draft. The polynomial expression of several important section is used to construct the basic outline of the three-dimensional bow with different width, bow length, angle of bow top and the possible maximum and its position. Then, I choose the bow length, angle of bow top and the possible maximum and its position as the optimization parameter. Finally, I reach the conclusion of a better-performing bow design for newer high-speed boat requirements and future studies are discussed.

Supplementary figures and figure legends Supplementary Figure 1. mTOR inhibitors do not impair homologous recombination repair in non-transformed breast epithelial cells. Supplementary Figure 2. mTOR inhibitors do not affect expression of key HR-related proteins in BRCA-proficient TNBCs. Supplementary Figure 3. Microarray and Ingenuity Pathway Analysis (IPA).

Surface discharge mechanism induced cathode passivation is a critical challenge that blocks the full liberation of the ultrahigh theoretical energy density in aprotic Li-O

Texture evolution of NiTiFe shape memory alloy (SMA) is investigated during plane strain compression based on crystal plasticity finite element method (CPFEM) and electron back-scatter diffraction (EBSD) experiment. The deformation textures of NiTiFe SMA are not influenced very considerably after experiencing recrystalline annealing at 600 °C for 1 h. Based on the results of CPFEM, the main activated slip systems of NiTiFe SMA are 〈100〉/{110} and 〈111〉/{110} ones during plane strain compression. According to the relationship between texture components and activated slip systems put forward in this study, 〈110〉 direction would rotate to rolling direction, whereas 〈100〉 and 〈111〉 directions would rotate to normal direction. These rotations contribute to the formation of γ-fibre texture and α-fibre texture in NiTiFe SMA. The deformation texture components predicted by CPFEM and determined by EBSD were compared with each other in detail. Due to the startup of the pencil glide and multiple slip in the refined microstructure, there are some differences between texture components predicted by CPFEM and texture components determined by EBSD. The deformation heterogeneity is discussed in terms of rotation angle at each integration point in the study.

Background LncRNA LINC00461 has been reported to play crucial regulatory roles in a variety of biological processes, including cell migration, cell invasion and cancer progression. However, its biological role in colorectal cancer (CRC) is completely unknown. The aim of our study was to explore the function of LINC00461 on CRC cells and the underlying mechanism. Materials and methods CRC tumor tissues and cell lines derived from hospital and corporation. The expression level of LINC00461 in CRC tissues and cell lines were analyzed by quantitative real-time PCR (qRT-PCR). The effect of LINC00461 on cell proliferation, colony formation, migration and invasion were detected by CCK-8 assay, colony formation and transwell assay, respectively. In addition, cell apoptosis was analyzed by flow cytometry, and the role of LINC00461 on tumor growth was investigated by tumor xenografts in nude mice. The targets of LINC00461 were predicted by starBase v3.0 and confirmed by a dual-luciferase reporter system. The expression level of transcription factors of nuclear factor I B (NFIB), p21 and CDK2 was determined by Western blot or qRT-PCR. The NFIB expression levels in CRC tissues and mice tumors were analyzed by immunofluorescence assay (IHC). Results We found that the expression of LINC00461 was significantly overexpressed in CRC tissues and different cell lines, and the high level of LINC00461 expression was associated with poor overall survival. Downregulation of LINC00461 expression significantly suppressed the proliferation, migration and invasion of CRC cells and promoted cell apoptosis. We also found that LINC00461 could directly interact with miR-323b-3p. In addition, LINC00461 significantly increased the expression NFIB and CDK2, but, p21 was inhibited. Finally, we found that the growth of tumors in nude mice was suppressed upon LINC00461 deletion. Conclusion We demonstrated that LINC00461 may play an oncogenic role in CRC cells through NFIB signaling pathway by targeting miR-323b-3p. Our report showed that LINC00461 may be a prognostic biomarker and candidate therapeutic target for CRC.

Treatment with immune checkpoint blockade (ICB) has resulted in durable responses for a subset of patients with cancer, with predictive biomarkers for ICB response originally identified largely in the context of hypermutated cancers. Although recent clinical data have demonstrated clinical responses to ICB in certain patients with non-hypermutated cancers, previously established ICB response biomarkers have failed to accurately identify which of these patients may benefit from ICB. Here, we demonstrate that a replication stress response (RSR) defect gene expression signature, but not other proposed biomarkers, is associated with ICB response in 12 independent non-hypermutated cohorts of patients with cancer across 7 tumor types, including those of the breast, prostate, kidney, and brain. Induction or suppression of RSR deficiencies was sufficient to modulate response to ICB in pre-clinical models of breast and renal cancers. Mechanistically, we find that despite robust activation of checkpoint kinase 1 (Chk1) signaling in RSR-deficient cancer cells, aberrant replication origin firing causes exhaustion of replication protein A, resulting in accumulation of immunostimulatory cytosolic DNA. We further found that deficient RSR coincided with increased intratumoral dendritic cells in both mouse cancer models and human tumors. Together, this work demonstrates the RSR defect gene signature can accurately identify patients who may benefit from ICB across numerous non-hypermutated tumor types, and pharmacological induction of RSR defects may further expand the benefits of ICB to more patients.

Autophagy has an important role in regulating tumor cell survival. However, the roles of autophagy-related genes (ARGs) during colon adenocarcinoma (COAD) progression and their prognostic value have remained elusive. The present study aimed to identify the correlation between ARGs and the progression of COAD, as well as the prognostic significance of ARGs. The transcriptome profiles and the corresponding clinicopathological information of patients with COAD were downloaded from The Cancer Genome Atlas and Genotype-Tissue Expression databases. A list of ARGs was obtained from the Human Autophagy Database and bioinformatics analysis was performed to investigate the functions of these ARGs. Statistical analyses of these genes were performed to identify independent prognostic markers. The selected prognostic markers were then validated in 15 patients with COAD via immunohistochemistry. Differentially expressed ARGs between normal and tumor tissues were identified. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that the differentially expressed ARGs were mainly enriched in toxoplasmosis and pathways in cancer. The ATG4B, DAPK1 and SERPINA1 genes were determined to be associated with COAD progression. In addition, a risk signature was proposed that may serve as an independent prognostic marker. In conclusion, ATG4B, DAPK1 and SERPINA1 are crucial participants in tumorigenesis of COAD. The present study may promote the development of novel treatment strategies for COAD.

Objective:To observe the changes of cytokines in serum of rabbits with acute pulmonary embolism, and to provide scientific basis for clinical treatment of the disease.Methods: The animal models of pulmonary embolism were established in 26 healthy rabbits by autologous thrombus reinfusion and normal saline injection, and the serum levels of cytokines (TNF-α, IL-1β, HGF) in the two groups were monitored by enzyme-linked immunosorbent assay.Results: The expression levels of serum inflammatory cytokines (TNF-α, IL-1β) increased in both groups of rabbits within 1-3 hours of the acute stage of embolism, but the expression levels of serum inflammatory cytokines in experimental group of rabbits with pulmonary embolism caused by thrombosis increased more obviously；There was no significant change in serum HGF of rabbits before and after embolization in group B. The serum HGF content of experimental rabbits at 1h, 3h, 12h, 24h and 48h after embolization was significantly higher than that before embolization.And in the acute stage of embolism (1-12 hours), it showed a gradual upward trend.Conclusion: The expression level of serum growth factor is different in different acute stages of pulmonary embolism. Detecting serum cytokines in rabbits with acute pulmonary embolism is of great reference significance for improving clinical diagnosis.

Nucleotide excision repair (NER) resolves DNA adducts, such as those caused by ultraviolet light. Deficient NER (dNER) results in a higher mutation rate that can predispose to cancer development and premature ageing phenotypes. Here, we used isogenic dNER model cell lines to establish a gene expression signature that can accurately predict functional NER capacity in both cell lines and patient samples. Critically, none of the identified NER deficient cell lines harbored mutations in any NER genes, suggesting that the prevalence of NER defects may currently be underestimated. Identification of compounds that induce the dNER gene expression signature led to the discovery that NER can be functionally impaired by GSK3 inhibition, leading to synergy when combined with cisplatin treatment. Furthermore, we predicted and validated multiple novel drugs that are synthetically lethal with NER defects using the dNER gene signature as a drug discovery platform. Taken together, our work provides a dynamic predictor of NER function that may be applied for therapeutic stratification as well as development of novel biological insights in human tumors.

BackgroundSubarachnoid hemorrhage (SAH) is a cerebrovascular disease associated with high morbidity and mortality. CXCR4 provides a neuroprotective effect, which can alleviate brain injury and inflammation induced by stroke. The purpose of this study was to evaluate the anti-inflammatory effects and mechanisms of CXCR4 after SAH. Methods: SAH was induced via endovascular perforation. 185 male Sprague-Dawley rats were used. Recombinant human cysteine-X-cysteine chemokine ligand 12 (rh-CXCL-12) was administered intranasally at 1 h after SAH induction. To investigate the underlying mechanism, the inhibitors of CXCR4 and P13K, AMD3100 and LY294002, respectively, were administered intraperitoneally at 1 h before SAH. The short- and long-term neurobehavior were assessed, followed by performing western blot and immunofluorescence staining. ResultsWestern blotting suggested that the expressions of endogenous CXCL-12 and CXCR4 were increased, and peaked at 24 h following SAH. Immunofluorescence staining showed that CXCR4 was expressed on microglia. Rh-CXCL-12 treatment reduced the number of M1 macrophages and improved the short- and long-term neurological deficits after SAH. Meanwhile, rh-CXCL-12 treatment increased the levels of CXCL-12, CXCR4, PI3K, and p-Akt, and reduced the levels of IL-1β, IL-6, and TNF-α. Moreover, the administration of AMD3100 and LY294002 abolished the post-SAH neurobehavioral and neuroinflammatory improvements of CXCL-12 and its regulation of PI3K and p-Akt protein levels.Conclusions The CXCR4/PI3K/Akt signaling pathway may be involved in CXCL-12-mediated reduction of post-SAH neuroinflammation. Early administration of CXCL-12 may be a preventive and therapeutic strategy against delayed brain injury after SAH.

Purpose — To explore the immune rejection of xenotransplantation of bone fracture hematoma cells in rabbits. Way — Lan Tu was used as the donor for allogeneic transplantation of fracture hematoma cells. Twelve New Zealand white rabbits were selected to establish the fracture model. The fracture hematoma cells of Lan Tu were transplanted to the broken end of the experimental group of New Zealand white rabbits, while the rabbits in the control group were not transplanted with allogeneic fracture hematoma cells. To observe the expression level of allogeneic fracture hematoma cells in the fracture site, and to analyze the rejection caused by xenotransplantation by observing the number of macrophages in the fracture model section and lymphoid follicles in the recipient spleen. Result — On the 7th and 12th day after transplantation, the hematoma cells in the fractured end of rabbits in the experimental group showed a decreasing trend, but their survival still met the needs of treatment. The results of immunohistochemical examination on the fractured bone tissue and spleen of the two groups of rabbits showed that there was no significant difference between the macrophage content in the fractured bone tissue and the lymphocyte follicular count in the spleen tissue of the two groups of rabbits in different transplantation time (P > 0.05). Conclusion — Using allogeneic hematoma cell transplantation to treat fractures will not cause excessive rejection of receptors, which is worthy of further clinical discussion and provides a favorable scientific reference for its application in clinical treatment of fractures.

In order to study the accelerated aging law of nitrate ester plasticized polyether (NEPE) propellants, the mechanical properties, weight loss, adhesive network structure fracture, and stability of NEPE propellants during storage were analyzed. The results show that the maximum tensile strength σm shows good change law with the increase of storage time, and the failure of NEPE propellants is mainly strength failure. The content of the stabilizer decreased with the increase of storage time. With the prolongation of storage time, the weight loss ratio increases gradually with good regularity. The decomposition of the components in the propellant leads to the degradation of the polyethylene glycol (PEG) network structure. The thermal decomposition of the nitrate plasticizer in NEPE propellants will occur, and the products will cause the adhesive network structure to decompose and break the chain, leading to the destruction of the matrix structure. The thermal decomposition of the propellant has temperature-increasing rate dependency.

The effect of plane strain compression and subsequent recrystallization annealing on microstructures and phase transformation of NiTiFe shape memory alloy (SMA) is investigated. Inhomogeneous plastic deformation at various deformation degrees occurs in NiTiFe SMA during plane strain compression. Nanocrystalline phase and amorphous phase increase as the deformation degree increases. B2 austenite, B19′ martensite, nanocrystalline and amorphous phases coexist in the NiTiFe samples subjected to large plastic strain. The static recrystallization mechanisms depend on the microstructures of the deformed NiTiFe samples. The static recrystallization mechanisms deal with nucleation and growth of the recrystallized grains, growth of nanocrystalline phase and crystallization of amorphous phase. Grain size, subgrain boundaries, geometrically necessary dislocation density and Schmid factor are captured on the basis of electron backscattered diffraction data. The process of recrystallization annealing cannot eliminate the deformation texture completely. The slip direction [110] is the most favorable slip direction in the recrystallized NiTiFe sample. Plane strain compression along with subsequent recrystallization annealing changes the phase transformation path of as-rolled NiTiFe SMA, and it results in the decreasing martensite transformation start temperature. The three annealed NiTiFe samples exhibit the similar phase transformation behavior since complete recrystallization annealing leads to the similar microstructures.

Three different NiTi-based alloys, whose nominal compositions were Ni50Ti50, Ni49Ti49Fe2, Ni45Ti51.8Fe3.2 (mole fraction, %), respectively, were used in the current research to understand the influence of Fe addition on phase transformation behavior in NiTi shape memory alloy (SMA). The microstructure and phase transformation behavior of the alloys were investigated by optical microscopy (OM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis. The results show that the matrix of the Ni50Ti50 alloy consists of both B19′ (martensite) phase and B2 (austenite) phase. Moreover, the substructures of twins could be observed in the B19′ phase. However, the ternary alloys of NiTiFe exhibit B2 phase in the microstructures. Such microstructures were also characterized by large presence of Ti2Ni precipitates dispersed homogenously in the matrix of the two kinds of alloys. The addition of Fe to the NiTi SMA results in the decrease in phase transformation temperatures in the ternary alloys. Based on mechanism analysis, it can be concluded that this phenomenon is primarily attributed to atom relaxation of the distorted lattice induced by Ni-antisite defects and Fe substitutions during phase transformation, which enables stabilization of B2 phase during phase transformation.

Based on equiatomic nickel and titanium, three kinds of NiTiFe alloys with a nominal chemical composition of Ni49Ti49Fe2, Ni48Ti48Fe4 and Ni47Ti47Fe6 (at.%), respectively, have been designed to investigate the influence of the addition of Fe element on phase transformation, microstructure and mechanical property of equiatomic NiTi shape memory alloy. The microstructures of three kinds of NiTiFe alloys are characterized by the equiaxed grains instead of the dendrites. Consequently, some Ti2Ni precipitates are found to distribute in the grains interior and at the grain boundaries. The content of Fe element has an important influence on mechanical property of NiTiFe alloy. With increasing content of Fe element, the strength of NiTiFe alloy increases substantially, but the plasticity decreases sharply. It can be concluded that precipitation strengthening and solution strengthening play a significant role in enhancing the strength of NiTiFe alloy. In the case of three NiTiFe alloys, neither martensitic transformation nor reverse transformation can be observed in the range from −150 to 150 °C. On the one hand, the phase transformation temperature is probably out of the scope of the present experimental temperature. On the other hand, the addition of Fe element probably suppresses first-order martensitic transformation or reverse transformation, and consequently the second-order-like phase transformation from an incommensurate stage to a commensurate stage can probably take place.

Crystal plastic finite element method (CPFEM) is used to simulate microstructural evolution, texture evolution and macroscopic stress-strain response of polycrystalline NiTiFe shape memory alloy (SMA) with B2 austenite phase during compression deformation. A novel two-dimensional polycrystalline finite element model based on electron back-scattered diffraction (EBSD) experiment data is developed to represent virtual grain structures of polycrystalline NiTiFe SMA. In the present study, CPFEM plays a significant role in predicting texture evolution and macroscopic stress-strain response of NiTiFe SMA during compression deformation. The simulated results are in good agreement with the experimental ones. It can be concluded that intragranular and intergranular strain heterogeneities are of great importance in guaranteeing plastic deformation compatibility of NiTiFe SMA. CPFEM is able to capture the evolution of grain boundaries with various misorientation angles for NiTiFe SMA subjected to the various compression deformation degrees. During uniaxial compression of NiTiFe SMA, the microstructure evolves into high-energy substructure and consequently the well-defined subgrains are formed. Furthermore, the grain boundaries and the subgrain boundaries are approximately aligned with the direction in which metal flows.

Deficient DNA mismatch repair (dMMR) induces a hypermutator phenotype that can lead to tumorigenesis; however, the functional impact of the high mutation burden resulting from this phenotype remains poorly explored. Here, we demonstrate that dMMR-induced destabilizing mutations lead to proteome instability in dMMR tumors, resulting in an abundance of misfolded protein aggregates. To compensate, dMMR cells utilize a Nedd8-mediated degradation pathway to facilitate clearance of misfolded proteins. Blockade of this Nedd8 clearance pathway with MLN4924 causes accumulation of misfolded protein aggregates, ultimately inducing immunogenic cell death in dMMR cancer cells. To leverage this immunogenic cell death, we combined MLN4924 treatment with PD1 inhibition and found the combination was synergistic, significantly improving efficacy over either treatment alone.

Three novel NiTiNb shape memory alloys, which possess a nominal chemical composition of Ni50−x/2-Ti50−x/2-Nb x (at.%) where x stands for 2, 4 and 6, respectively, were designed in order to investigate the influence of the addition of Nb on phase transformation, microstructure and mechanical properties of equiatomic NiTi shape memory alloy. All the three NiTiNb shape memory alloys contain B2 austenite phase, B19′ martensite phase and β-Nb precipitate phase. Martensite type II twin can be observed in the case of Ni49Ti49Nb2 alloy. In the case of Ni48Ti48Nb4 alloy, there exists a boundary between Ti2Ni precipitate phase and β-Nb precipitate phase. As for Ni47Ti47Nb6 alloy, it can be observed that there exists an orientation relationship of $$ [01\bar{1}]_{{\upbeta{\text{ - Nb}}}} //[01\bar{1}]_{\text{B2}} $$ between β-Nb precipitate phase and B2 austenite matrix. The increase in Nb content contributes to enhancing the yield stress of NiTiNb shape memory alloy, but it leads to the decrease in compression fracture stress. The addition of Nb to equiatomic NiTi shape memory alloy does not have a significant influence on the transformation hysteresis of the alloy, which is attributed to the fact that NiTiNb shape memory alloy is not subjected to plastic deformation and hence β-Nb precipitate phase is unable to relax the elastic strain in the martensite interface.

Based on ternary Ni45Ti51.8Fe3.2 (at %) shape memory alloy (SMA), Nb and Ta elements are added to an NiTiFe SMA by replacing Ni element, and consequently quaternary Ni44Ti51.8Fe3.2Nb1 and Ni44Ti51.8Fe3.2Ta1 (at %) SMAs are fabricated. The microstructure, mechanical property, and phase transformation of NiTiFeNb and NiTiFeTa SMAs are further investigated. Ti2Ni and β-Nb phases can be observed in NiTiFeNb SMA, whereas Ti2Ni and Ni3Ti phases can be captured in NiTiFeTa SMA. As compared to NiTiFe SMA, quaternary NiTiFeNb and NiTiFeTa SMAs possess the higher strength, since solution strengthening plays a considerable role. NiTiFeNb and NiTiFeTa SMAs exhibit a one-step transformation from B2 austenite to B19’ martensite during cooling, but they experience a two-step transformation of B19’-R-B2 during heating.

DNA double-strand breaks (DSBs) serve as obligatory intermediates for Ig heavy chain (Igh) class switch recombination (CSR). The mechanisms by which DSBs are resolved to promote long-range DNA end-joining while suppressing genomic instability inherently associated with DSBs are yet to be fully elucidated. Here, we use a targeted short-hairpin RNA screen in a B-cell lymphoma line to identify the BRCT-domain protein BRIT1 as an effector of CSR. We show that conditional genetic deletion of BRIT1 in mice leads to a marked increase in unrepaired Igh breaks and a significant reduction in CSR in ex vivo activated splenic B cells. We find that the C-terminal tandem BRCT domains of BRIT1 facilitate its interaction with phosphorylated H2AX and that BRIT1 is recruited to the Igh locus in an activation-induced cytidine deaminase (AID) and H2AX-dependent fashion. Finally, we demonstrate that depletion of another BRCT-domain protein, MDC1, in BRIT1-deleted B cells increases the severity of CSR defect over what is observed upon loss of either protein alone. Our results identify BRIT1 as a factor in CSR and demonstrate that multiple BRCT-domain proteins contribute to optimal resolution of AID-induced DSBs.

Based on the local canning compression, severe plastic deformation (SPD) is able to lead to the almost complete amorphous nickel-titanium shape memory alloy (NiTi SMA), in which a small amount of retained nanocrystalline phase is embedded in the amorphous matrix. Crystallization of amorphous NiTi alloy annealed at 573, 723 and 873 K was investigated, respectively. The crystallization kinetics of the amorphous NiTi alloy can be mathematically described by the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation. NiTi SMA with a complete nanocrystalline phase is obtained in the case of annealing at 573 K and 723 K, where martensite phase transformation is suppressed due to the constraint of the grain boundaries. Crystallization of amorphous NiTi alloy at 873 K leads to the coarse-grained NiTi sample, where (001) martensite compound twin is observed at room temperature. It can be found that the martensitic twins preferentially nucleate at the grain boundary and they grow up towards the two different grains. SPD based on the local canning compression and subsequent annealing provides a new approach to obtain the nanocrystalline NiTi SMA.

As-received nickel–titanium (NiTi) shape memory alloy with a nominal composition of Ni50.9Ti49.1 (mole fraction, %) was subjected to solution treatment at 1123 K for 2 h and subsequent aging for 2 h at 573 K, 723 K and 873 K, respectively. The influence of solution treatment and aging on microstructural evolution and mechanical behavior of NiTi alloy was systematically investigated by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM) and compression test. Solution treatment contributes to eliminating the Ti2Ni phase in the as-received NiTi sample, in which the TiC phase is unable to be removed. Solution treatment leads to ordered domain of atomic arrangement in NiTi alloy. In all the aged NiTi samples, the Ni4Ti3 precipitates, the R phase and the B2 austenite coexist in the NiTi matrix at room temperature, while the martensitic twins can be observed in the NiTi samples aged at 873 K. In the NiTi samples aged at 573 and 723 K, the fine and dense Ni4Ti3 precipitates distribute uniformly in the NiTi matrix, and thus they are coherent with the B2 matrix. However, in the NiTi sample aged at 873 K, the Ni4Ti3 precipitates exhibit the very inhomogeneous size, and they are coherent, semi-coherent and incoherent with the B2 matrix. In the case of aging at 723 K, the NiTi sample exhibits the maximum yield strength, where the fine and homogeneous Ni4Ti3 precipitates act as the effective obstacles against the dislocation motion, which results in the maximum critical resolved shear stress for dislocation slip.

As a new attempt, local canning compression was applied in order to implement large plastic deformation of nickel-titanium shape memory alloy (NiTi SMA) at room temperature. The plastic mechanics of local canning compression of NiTi SMA was analyzed according to the slab method as the well as plastic yield criterion. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM) were used to study the microstructural evolution as well as deformation behavior of NiTi samples under local canning compression. Increasing the hydrostatic pressure with the increase in the outer diameters of the steel cans is responsible for suppressing the initiation and growth of the micro-cracks, which contributes to enhancing the plasticity of NiTi SMA and avoiding the occurrence of brittle fracture. Plastic deformation of NiTi SMA under a three-dimensional compressive stress state meets von-Mises yield criterion at the true strains ranging from about 0.15 to 0.50, while in the case of larger plastic strain, von-Mises yield criterion is unable to be met since the amorphous phase arises in the deformed NiTi sample.

In humans, the gene encoding the BRCA1 C terminus-repeat inhibitor of human telomerase expression 1 (BRIT1) protein is located on chromosome 8p23.1, a region implicated in the development of several malignancies, including breast cancer. Previous studies by our group and others suggested that BRIT1 might function as a novel tumor suppressor. Thus, identifying the molecular mechanisms that underlie BRIT1's tumor suppressive function is important to understand cancer etiology and to identify effective therapeutic strategies for BRIT1-deficient tumors. We thus investigated the role of BRIT1 as a tumor suppressor in breast cancer by using genetic approaches. We discovered that BRIT1 functions as a post-transcriptional regulator of p53 expression. BRIT1 regulates p53 protein stability through blocking murine double minute 2-mediated p53 ubiquitination. To fully demonstrate the role of BRIT1 as a tumor suppressor, we depleted BRIT1 in normal breast epithelial cells. We found that knockdown of BRIT1 caused the oncogenic transformation of normal mammary epithelial cells. Furthermore, ectopic expression of BRIT1 effectively suppressed breast cancer cell proliferation and colony formation in vitro and tumor growth in vivo. Taken together, our study provides new insights into the biological functions of BRIT1 as a tumor suppressor in human breast cancer.

As a severe plastic deformation (SPD) technique, local canning compression provides a novel approach to produce bulk amorphous and nanocrystalline nickel–titanium shape memory alloy (NiTi SMA). From the macroscale, mesoscale and microscale viewpoint, physical mechanism of inhomogeneous plastic deformation of NiTi alloy under local canning compression is investigated by means of optical microscopy, transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Inhomogeneous plastic deformation of NiTi alloy leads to coexistence of amorphous phase, nanocrystalline phase, B2 austenite and B19′ martensite. The interaction between the dislocations and the grain boundaries lays the profound foundation for guaranteeing the continuity and the compatibility between the grains in a polycrystalline NiTi sample subjected to inhomogeneous plastic deformation. Deformation twinning and dislocation slip are the two important deformation modes in plastic deformation of NiTi alloy under local canning compression. Based on the statistically stored dislocation and the geometrically necessary dislocation, the mechanism of the critical dislocation density plays a predominant role in the occurrence of the amorphous phase in the deformed NiTi sample. When the deformation temperature is higher than a critical temperature, the amorphous phase is not able to occur in the NiTi sample subjected to SPD.

As a new method for severe plastic deformation (SPD), local canning compression was applied in order to fabricate amorphous and nanocrystalline nickel–titanium shape memory alloys (NiTi SMA) at room temperature. Transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) were used for understanding microstructural evolution as well as deformation mechanism of NiTi SMA under local canning compression. Deformation mechanism of NiTi alloy under local canning compression involves stress-induced martensite transformation, deformation twinning, dislocation slip, nanocrystallization and amorphization. The (001) martensite compound twins, the stacking faults, primary deformation bands, secondary deformation bands and amorphous bands are observed in the NiTi sample subjected to SPD. The (001) martensite compound twins belong to the deformation twins and thus lead to mechanical stabilization of stress-induced martensite. Deformation twinning and dislocation slip are of great importance in amorphization and nanocrystallization of NiTi SMA subjected to SPD based on local canning compression.

Dynamic recrystallization (DRX) occurs in NiTi alloy during compression deformation at the strain rates of 0.001–1 s −1 and at the temperatures of 800–1000 °C. Cellular automaton (CA) model is used for understanding physical mechanism of DRX of NiTi alloy so that the microstructural evolution, the dislocation density, the flow stress and the grain size are simulated and predicted. The recrystallized grains firstly nucleate at the grain boundaries of the grains in the initial microstructure, where the dislocation density reaches the critical value. DRX is characterized by repeated nucleation and finite growth of the recrystallized grains. The dislocation density decreases with the increase in the deformation temperature, but increases with the increase in the strain rate. The fluctuation of the simulated stress–strain curve is almost the same as the fluctuation of the dislocation density, which is responsible for the competition between hardening and softening. The recrystallized grain size increases with the increase in the deformation temperature, but decreases with the increase in the strain rate. In the case of a given temperature and a given strain rate, the grain size in the initial microstructures has almost no influence on the grain size in the resultant DRX microstructures.

Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer with poor prognosis and is enriched in cancer stem cells (CSCs). However, it is not completely understood how the CSCs were maintained in TNBC. In this study, by analyzing The Cancer Genome Atlas (TCGA) provisional datasets and several small-size breast datasets, we found that cadherins (CDHs) 2, 4, 6, and 17 were frequently amplified/overexpressed in 47% of TNBC while E-cadherin (CDH1) was downregulated/mutated at 10%. The alterations of CDH2/4/6/17 were strongly associated with the elevated levels of several stem cell-related transcription factors (SC-TFs) including FOXM1, MCM2, WWTR1, SNAI1, and SOX9. CDH2/4/6/17-enriched genes including FOXM1 and MCM2 were also clustered and regulated by NFY (nuclear transcription factor Y) and/or EVI1/MECOM. Meanwhile, these SC-TFs including NFYA were upregulated in TNBC cells, but they were downregulated in luminal type of cells. Furthermore, small compounds might be predicted via the Connectivity Map analysis to target TNBC with the alterations of CDH2/4/6/17 and SC-TFs. Together with the important role of these SC-TFs in the stem cell regulation, our data provide novel insights into the maintenance of CSCs in TNBC and the discovery of these SC-TFs associated with the alterations of CDH2/4/6/17 has an implication in targeted therapy of TNBC.

More aggressive and therapy-resistant oestrogen receptor (ER)-positive breast cancers remain a great clinical challenge. Here our integrative genomic analysis identifies tousled-like kinase 2 (TLK2) as a candidate kinase target frequently amplified in ∼10.5% of ER-positive breast tumours. The resulting overexpression of TLK2 is more significant in aggressive and advanced tumours, and correlates with worse clinical outcome regardless of endocrine therapy. Ectopic expression of TLK2 leads to enhanced aggressiveness in breast cancer cells, which may involve the EGFR/SRC/FAK signalling. Conversely, TLK2 inhibition selectively inhibits the growth of TLK2-high breast cancer cells, downregulates ERα, BCL2 and SKP2, impairs G1/S cell cycle progression, induces apoptosis and significantly improves progression-free survival in vivo. We identify two potential TLK2 inhibitors that could serve as backbones for future drug development. Together, amplification of the cell cycle kinase TLK2 presents an attractive genomic target for aggressive ER-positive breast cancers., Luminal B oestrogen receptor positive breast cancers are generally aggressive tumors with poor outcomes. Here, the authors show that the kinase TLK2 is amplified and overexpressed in these tumors and correlates with reduced survival, TLK2 inhibition induces apoptosis in vitro and improves survival in mice.

Estrogen receptor α (ERα) is a master driver of a vast majority of breast cancers. Breast cancer cells often develop resistance to endocrine therapy via restoration of the ERα activity through survival pathways. Thus identifying the epigenetic activator of ERα that can be targeted to block ERα gene expression is a critical topic of endocrine therapy. Here, integrative genomic analysis identified MYST3 as a potential oncogene target that is frequently amplified in breast cancer. MYST3 is involved in histone acetylation via its histone acetyltransferase domain (HAT) and, as a result, activates gene expression by altering chromatin structure. We found that MYST3 was amplified in 11% and/or overexpressed in 15% of breast tumors, and overexpression of MYST3 correlated with worse clinical outcome in estrogen receptor+ (ER+) breast cancers. Interestingly, MYST3 depletion drastically inhibited proliferation in MYST3-high, ER+ breast cancer cells, but not in benign breast epithelial cells or in MYST3-low breast cancer cells. Importantly, we discovered that knocking down MYST3 resulted in profound reduction of ERα expression, while ectopic expression of MYST3 had the reversed effect. Chromatin immunoprecipitation revealed that MYST3 binds to the proximal promoter region of ERα gene, and inactivating mutations in its HAT domain abolished its ability to regulate ERα, suggesting MYST3 functioning as a histone acetyltransferase that activates ERα promoter. Furthermore, MYST3 inhibition with inducible MYST3 shRNAs potently attenuated breast tumor growth in mice. Together, this study identifies the first histone acetyltransferase that activates ERα expression which may be potentially targeted to block ERα at transcriptional level.

Mammalian cells are frequently at risk of DNA damage from multiple sources. Accordingly, cells have evolved the DNA damage response (DDR) pathways to monitor the integrity of their genome. Conceptually, DDR pathways contain three major components (some with overlapping functions): sensors, signal transducers, and effectors. At the level of sensors, ATM (ataxia telangiectasia mutated) and ATR (ATM-Rad3-related) are proximal kinases that act as the core sensors of and are central to the entire DDR. These two kinases function to detect various forms of damaged DNA and trigger DNA damage response cascades. If cells harbor DDR defects and fail to repair the damaged DNA, it would cause genomic instability and, as a result, lead to cellular transformation. Indeed, deficiencies of DDR frequently occur in human cancers. Interestingly, this property of cancer also provides a great opportunity for cancer therapy. For example, by using a synthetic lethality model to search for the effective drugs, ChK1 inhibitors have been shown to selectively target the tumor cells with p53 mutations. In addition, the inhibitors of poly(ADP-ribose) polymerase (PARP-1) showed selectively killing effects on the cells with defects of homologous recombination (HR), particularly in the context of BRCA1/2 mutations. Since Brit1 is a key regulator in DDR and HR repair, we believe that we can develop a similar strategy to target cancers with Brit1 deficiency. Currently, we are conducting a high-throughput screening to identify novel compounds that specifically target the Brit1-deficient cancer which will lead to development of effective personalized drugs to cure cancer in clinic.

Microcephalin/MCPH1 is one of the causative genes responsible for the autosomal recessive disorder primary microcephaly. Patients with this disease present with mental retardation and dramatic reduction in head size, and cells derived from these patients contain abnormally condensed chromosomes. MCPH1 contains an N-terminal BRCT and tandem C-terminal BRCT domains. More recently, MCPH1 has been implicated in the cellular response to DNA damage; however, the exact mechanism remains unclear. Here, we report the identification Condensin II as a major MCPH1-interacting protein. MCPH1 and Condensin II interact in vivo, mediated by the CAPG2 subunit of Condensin II binding to a middle domain (residues 376-485) of MCPH1. Interestingly, while Condensin II is not required for the IR-induced G2/M checkpoint, Condensin II-depleted cells have a defect in HR repair, which is also present in MCPH1-/-MEFs. Moreover, the Condensin II binding region of MCPH1 is also required for HR function. Collectively, we have identified a novel function of MCPH1 to modulate HR repair through Condensin II, and thereby maintain genome integrity.

E-cadherin mediates calcium-dependent cell-cell adhesion between epithelial cells. The ectodomain of human E-cadherin contains four potential N-glycosylation sites at Asn residues 554, 566, 618, and 633. In this study, the role of N-glycosylation in E-cadherin-mediated cell-cell adhesion was investigated by site-directed mutagenesis. In MDA-MB-435 cells, all four potential N-glycosylation sites of human E-cadherin were N-glycosylated. Removal of N-glycan at Asn-633 dramatically affected E-cadherin stability. In contrast, mutant E-cadherin lacking the other three N-glycans showed similar protein stability in comparison with wild-type E-cadherin. Moreover, N-glycans at Asn-554 and Asn-566 were found to affect E-cadherin-mediated calcium-dependent cell-cell adhesion, and removal of either of the two N-glycans caused a significant decrease in calcium-dependent cell-cell adhesion accompanied with elevated cell migration. Analysis of the composition of adherens junctions (AJs) revealed that removal of N-glycans on E-cadherin resulted in elevated tyrosine phosphorylation level of beta-catenin and reduced beta- and alpha-catenins at AJs. These findings demonstrate that N-glycosylation may affect the adhesive function of E-cadherin through modifying the composition of AJs.

DNA methylation, which affects gene expression and chromatin stability, is catalyzed by DNA methyltransferases (DNMTs) of which DNMT1 possesses most abundant activity. PI3K/PKB pathway is an important pathway involved in cell proliferation, viability, and metabolism and often disrupted in cancer. Here we investigated the impact of PKB on DNMT1 and DNA methylation. Positive correlation between PKB-Ser473-phosphorylation and DNMT1 protein level in 17 human cell lines (p

We present here an effective technique for the large-scale separation and identification of N-linked glycoproteins from Chang liver cells, the human normal liver cells. To enrich N-linked glycoproteins from the whole cells, a procedure containing the lysis of human liver cells, the solubilization of total proteins, lectin affinity chromatography including Concanavalin A and wheat germ agglutinin was established. Furthermore, captured N-linked glycoproteins were separated by 2-DE, and identified by MS and database searching. Finally, we found 63 N-glycoproteins in Chang liver cells. In addition, using the above method, we identified 7 remarkably up-regulated glycoproteins from MHCC97-H cells, highly metastatic liver cancer cells, compared to Chang liver cells. These up-regulated glycoproteins were associated with liver cancer and might be used as biomarkers for tumor diagnosis. Results showed that we established a high-throughput proteomic analysis for separating N-linked glycoproteins from human liver cells. This strategy greatly improved the glycoprotein analysis method associated with proteome-wide glycosylation changes related to liver cancer. Our work was part of the HUPO Human Liver Proteome Project (HLPP) studies and was supported by CHINA HUPO.