Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma

Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expression of focal adhesion kinase(FAK),which increases the risk of metastasis and recurrence.Nevertheless,the efficacy of FAK phosphorylation inhibitors is currently limited.Thus,investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis.This study examined the correlation between FAK expression and the prognosis of HCC.Additionally,we explored the impact of FAK degradation on HCC metastasis through wound healing experiments,transwell invasion experiments,and a xenograft tumor model.The expression of proteins related to epithelial-mesenchymal transition(EMT)was measured to elucidate the underlying mechanisms.The results showed that FAK PROTAC can degrade FAK,inhibit the migration and invasion of HCC cells in vitro,and notably decrease the lung metastasis of HCC in vivo.Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited.Consequently,degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis,holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs.

Chaperone-mediated autophagy targeting chimeras (CMATAC) forthe degradation of ERα in breast cancer

Estrogen receptor alpha(ERα/ESR1)is overexpressed in over half of all breast cancers and is considered a valuable therapeutic target in ERαpositive breast cancer.Here,we designed a membrane-permeant Chaperonemediated Autophagy Targeting Chimeras(CMATAC)peptide to knockdown endogenous ERαprotein through chaperone-mediated autophagy.The peptide contains a cell membrane-penetrating peptide(TAT)that allows the peptide to by-pass the plasma membrane,anαI peptide as a protein-binding peptide(PBD)that binds specifically to ERα,and CMA-targeting peptide(CTM)that targeting chaperone-mediated autophagy.We validated that ERαtargeting peptide was able to target and degrade ERαto reduce the viability of ERαpositive breast cancer cells.Taken together,our studies provided a new method to reduce the level of intracellular ERαprotein via CMATAC,and thus may provide a new strategy for the treatment of ERαpositive breast cancer.

The Potential of Rat Inner Cell Mass and Fetal Neural Stem Cells to Generate Chimeras

The rat chimera is an important animal model for the study of complex human diseases. In the present study we evaluated the chimeric potential of rat inner cell masses （ICMs） and fetal neural stem （FNS） cells. In result, three rat chimeras were produced by day 5 （D5） Sprague-Dawley （SD） blastocysts injected with ICMs derived from day 6 （D6） and D5 Dark Agouti （DA） blastocysts; four rat chimeras had been generated by D5 DA blastocyst injected with D5 SD ICMs. For the requirement of gene modification, cultured rat inner cell mass cells were assessed to produce chimeras, but no chimeras were generated from injected embryos. The potential to generate chimeras from rFNS and transfected rFNS cells were tested, but no chimeric pups were produced. Only 2 of 41 fetuses derived from D5 DA blastocyst injection with SD LacZ transfected rFNS cells showed very low number of LacZ positive cells in the section. These results indicate that DA and SD rat ICMs arc able to contribute to chimeras, but their potential decreases significantly after culture in vitro （P〈0.05）, and rFNS cells only have the potential to contribute to early fetal development.

Production of chicken chimeras by fusing blastodermal cells with electroporation

Aim: To establish techniques for producing somatic and germline chimeric chicken by transferring blastodermal cellsfused with electroporation. Methods: Stage-X blastodermal cells isolated from freshly laid fertile unincubated whiteLeghorn and Rhode Island red chicken eggs were fused with electroporation. The treated cell suspension was transferredto the recovery medium (DMEM containing 10% FBS) and was injected into the subgenninal cavity of recipient unin-cubated embryos (stage X). Results: Of 177 recipient embryos injected with the fusing blastodermal cells, 6(3.4 %) survived to hatching. Somatic chimerism was examined in the melanocyte of the feather. The presence offeathers originating from the donor cell was observed in 1 bird (16.7%) out of the 6 hatched birds. After 21 days ofincubation two birds out of five embryos were subjected to polymerase chain reaction (PCR) analysis for W-chromo-some-specific DNA for each tissue. One bird possessed W-chromosome-specific DNA in the stomach, and the other ex-hibited the same DNA in the left and right gonads and other tissues, but not the stomach. Conclusion: Recipientembryo having electrofused blastodennal cells yields somatic and germline chimeric chickens more successfully.(Asian J Androl 2000 Dec; 2: 271-275)

Establishment of Embryonic Stem Cell Lines from C57BL/6J Mice and Generation of Chimeras

Four embryonic stem (ES) cell lines, designated CE1, CE2, CE3 and CE4, were isolated from C57BL/6J blastocysts. The ratio of normal diploid composition of these cell lines is above 70%. To examine the differentiation potential of the ES cells, the CE2 cells were injected subcutaneously into syngenic mice, and many kinds of differentiated cells were observed on the sections of the teratoma derived from this ES cell line. On the other hand, to test the chimeric ability of the ES cells, the CE2 cells were microinjected into the blastocysts of ICR mice, and a chimera was obtained among living pups. These results show that CE2 ES cells are pluripotent stem cells, which can differentiate into many kinds of cell types, and can be used as a cell system for further research.

Controlling chaos and supressing chimeras in a fractional-order discrete phase-locked loop using impulse control

A fractional-order difference equation model of a third-order discrete phase-locked loop(FODPLL) is discussed and the dynamical behavior of the model is demonstrated using bifurcation plots and a basin of attraction. We show a narrow region of loop gain where the FODPLL exhibits quasi-periodic oscillations, which were not identified in the integer-order model. We propose a simple impulse control algorithm to suppress chaos and discuss the effect of the control step. A network of FODPLL oscillators is constructed and investigated for synchronization behavior. We show the existence of chimera states while transiting from an asynchronous to a synchronous state. The same impulse control method is applied to a lattice array of FODPLL, and the chimera states are then synchronized using the impulse control algorithm. We show that the lower control steps can achieve better control over the higher control steps.

“Rigid-elastic chimera” pore skeleton model and overpressure porosity measurement method for shale: A case study of the deep overpressure siliceous shale of Silurian Longmaxi Formation in southern Sichuan Basin, SW China

Based on analysis of pore features and pore skeleton composition of shale,a“rigid elastic chimeric”pore skeleton model of shale gas reservoir was built.Pore deformation mechanisms leading to increase of shale porosity due to the pore skeleton deformation under overpressure were sorted out through analysis of stress on the shale pore and skeleton.After reviewing the difficulties and defects of existent porosity measurement methods,a dynamic deformed porosity measurement method was worked out and used to measure the porosity of overpressure Silurian Longmaxi Formation shale under real formation conditions in southern Sichuan Basin.The results show:(1)The shale reservoir is a mixture of inorganic rock particles and organic matter,which contains inorganic pores supported by rigid skeleton particles and organic pores supported by elastic-plastic particles,and thus has a special“rigid elastic chimeric”pore structure.(2)Under the action of formation overpressure,the inorganic pores have tiny changes that can be assumed that they don’t change in porosity,while the organic pores may have large deformation due to skeleton compression,leading to the increase of radius,connectivity and ultimately porosity of these pores.(3)The“dynamic”deformation porosity measurement method combining high injection pressure helium porosity measurement and kerosene porosity measurement method under ultra-high variable pressure can accurately measure porosity of unconnected micro-pores under normal pressure conditions,and also the porosity increment caused by plastic skeleton compression deformation.(4)The pore deformation mechanism of shale may result in the"abnormal"phenomenon that the shale under formation conditions has higher porosity than that under normal pressure,so the overpressure shale reservoir is not necessarily“ultra-low in porosity”,and can have porosity over 10%.Application of this method in Well L210 in southern Sichuan has confirmed its practicality and reliability.

45,X/47,XYY性发育异常一例并文献复习

45,X/47,XYY性发育异常是一种由于罕见的染色体异常导致的性发育异常疾病。报告1例收治的45,X/47,XYY嵌合型性发育异常患者,该患者主因原发性闭经并出现男性化表现就诊,具有特纳综合征(Turner syndrome,Turner综合征)的表现,腹腔镜探查显示一侧性腺为条索状,另一侧外观睾丸样,病理为卵睾型性腺,手术切除双侧附件并予人工周期治疗,有月经来潮。结合本例及检索到的文献报道的女性表型中因原发性闭经就诊的病例共11例,对该病的临床表现、诊断及治疗方式进行总结。女性表型45,X/47,XYY性发育异常患者临床表现多样,以Turner综合征表现合并男性化表现多见,应尽早发现并切除发育不良的性腺,防止性腺肿瘤的发生和男性化表现出现。术后进行长期激素替代治疗,同时注重患者精神心理的疏导。

1例错误否定父权的嵌合体STR分析

随着科学技术的不断发展,亲子鉴定中的嵌合体案例逐渐被发现。亲子鉴定目前通常是在现场采取血样,也有少数机构采取口腔拭子进行STR分型检测。在排除医源性人造异源嵌合体和检材被污染风险因素后,当不同基因座出现多个等位基因异常情况时,往往会考虑被检者为先天嵌合体。但是,如果嵌合体的血液中只存在一种细胞群的时候,血样常染色体STR分型不会出现异常,很容易得出错误的鉴定结论,直接排除亲缘关系。本文所分析案例,就属此类非常罕见的情况。

基于Chimera网格的固定床反应器内局部流动模拟

采用基于三维Chimera网格的有限体积方法对球形颗粒随机填充的固定床内部小Reynolds数(9～50)下的局部流动进行了数值模拟。为了考察固定床内局部流动特点,本文模拟的固定床反应器的填充颗粒的数目较大,分别为120和500,直径比(固定床内径与填充颗粒直径之比)分别为7和10。由于计算量巨大,采用了基于PVM的分布式并行计算。模拟结果提供了固定床内局部流动的详细流场信息,显示了流动的不均匀性、壁面效应和沟流的存在。为固定床内进一步的流动与传热及反应耦合研究奠定了基础。

介绍一款优秀的分子图形软件Chimera

为提高信息技术在化学科研教育中的应用,介绍了一款名为UCSF chimera的优秀的分子图形软件,其自由的可视化功能及其他附属工具使用方便,在生物、医药、化学的科研、教育等方面都有着广泛的用途。

FOXN1基因敲除兔嵌合体的建立

目的建立F0代FOXN1基因敲除兔嵌合体,以探究普通饲养环境免疫缺陷兔活体保种的方法。方法首先,利用CRISPR/Cas9技术,将构建好的sgRNA和Cas9蛋白注入兔二细胞期胚胎的一个细胞中,以获得FOXN1基因编辑嵌合体胚胎。然后,胚胎移植至代孕母兔。最后,通过PCR技术以及Sanger测序方法鉴定F0代仔兔基因型,并观察其在普通饲养环境生长发育的情况。结果PCR结合Sanger测序结果表明FOXN1基因敲除兔嵌合体构建成功。经观察,嵌合体在普通环境下生长发育良好,无免疫缺陷表型。结论本研究初步建立了在普通环境下可正常生长发育的FOXN1基因敲除兔嵌合体,为后续进一步繁育FOXN1免疫缺陷兔奠定了研究基础。

新型BTK PROTAC降解剂的设计合成及活性评价

目的设计合成系列以伊布替尼类似物为布鲁顿酪氨酸激酶(bruton′s tyrosine kinase,BTK)激酶配体的蛋白降解靶向嵌合体(proteolysis targeting chimeras,PROTAC)降解剂,并初步评价其体外活性。方法以3-(4-苯氧基苯基)-1H-吡唑并[3,4-d]嘧啶-4-胺为起始原料,通过取代、还原胺化、脱保护和水解等反应合成一系列新型PROTAC;通过MTS法和蛋白免疫印迹法(Western-blot)分别测定目标化合物对OCI-LY10细胞的增殖抑制能力和BTK降解活性;通过分子对接考察分子配体与BTK蛋白的结合模式。结果共合成了14个BTK PROTAC降解剂,大部分化合物都具有一定的体外活性,其中化合物15a表现出了较好的细胞增殖抑制活性(IC_(50)=7.15 nmol·L^(-1))和BTK降解活性(DC_(50)<10 nmol·L^(-1))。结论合成了结构新颖、活性较好的BTK PROTAC降解剂,对其构效关系进行了初步探索,可为BTK PROTAC降解剂的进一步研究提供参考。

45,X/46,XY染色体嵌合型不育症一例

45,X/46,XY染色体嵌合是临床上比较少见的疾病,具有这种嵌合核型的患者可表现为男性或者女性外观,临床特征相似于特纳综合征(Turner syndrome,Turner综合征),但症状轻于Turner综合征。报告1例因不育就诊的男性表型患者,经G显带染色体核型分析和全基因组拷贝数变异(copy number variation,CNV)技术分析患者外周血提取的DNA,染色体核型诊断为45,X/46,XY嵌合型,外周血淋巴细胞染色体核型共分析50个染色体核型,核型诊断结果为45,X[27]/46,XY[23],全基因组CNV检测结果为-(mosaic)(Y)(64%),Y染色体微缺失检测结果为未见明显异常。45,X/46,XY染色体嵌合型男性表型案例较少,本例患者身材矮小,生殖器畸形,是临床表型较轻的男性表型患者。

新型布鲁顿氏酪氨酸激酶蛋白水解靶向嵌合体(BTK PROTAC)的设计合成及活性评价

目的 设计合成新型布鲁顿氏酪氨酸激酶蛋白水解靶向嵌合体(BTK PROTAC),并在体外评估这些分子对BTK蛋白的降解活性。方法 以Nurix Therapeutics公司临床化合物NX-5948为先导化合物,分析其与靶蛋白的相互作用,通过引入并环代替吡嗪胺的骨架跃迁思路对其进行结构改造,成功合成了一系列新型BTK PROTACs,通过时间分辨荧光共振能量转移技术(TR-FRET)、MTS法和蛋白质免疫印迹法分别测定目标化合物的激酶活性、细胞增殖抑制活性和BTK蛋白降解活性。结果 共合成6个目标化合物(化合物B~G),活性测试结果显示,大部分化合物都具有优异的细胞增殖抑制活性和BTK降解活性,其中化合物B表现出较优的BTK蛋白降解能力,其半数最大降解浓度(DC_(50))值约为0.1 nmol·L^(-1)。结论 基于NX-5948,通过骨架跃迁的方法设计合成了一类新颖的BTK PROTAC化合物,进行了构效关系的初步探索,可为BTK PROTAC降解剂的进一步研究提供参考。

小分子药物筛选技术研究现状及其应用进展

小分子药物筛选技术伴随着药物的发现正在不断更新和拓展,药物筛选技术的创新可以提高研发效率和成功率、缩短研发周期、降低成本。从基于已知活性化合物和高通量筛选等传统筛选技术,到基于结构的药物发现、基于片段的药物发现、DNA编码化合物库、蛋白降解靶向联合体等新技术,小分子药物筛选技术在不断拓宽小分子药物的市场潜力。该文将介绍目前小分子药物筛选技术整体现状,系统综述各技术及其优劣势,为小分子药物筛选新技术的发展提供重要参考。

基于PROTAC技术的EGFR降解剂的合成

表皮生长因子受体(EGFR)是治疗非小细胞肺癌(NSCLC)的有效靶点,但获得性耐药极大地限制了EGFR小分子抑制剂的临床疗效。PROTAC技术有望通过蛋白降解克服耐药性问题。基于PROTAC技术设计并合成了6个靶向EGFR的降解剂,并进行了药理活性评价。Western blot测试结果显示化合物Ⅶ能有效地诱导EGFR^(del19/T790M/C797S)和EGFR^(L858R/T790M/C797S)突变蛋白的降解,细胞增殖抑制活性测试显示化合物Ⅶ能抑制Ba/F3-EGFR^(del19/T790M/C797S)和Ba/F3-EGFR^(L858R/T790M/C797S)细胞的增殖,半抑制浓度(IC_(50))值分别为8.072 nmol/L和7.675 nmol/L。

An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

In this paper,an intelligent control method applying on numerical virtual flight is proposed.The proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application prospect.Firstly,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is constructed.In order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried out.The simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight simulation.Secondly,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy respectively.The intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight parameters.Compared with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability error.The intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

Development of PROTACS degrading KRAS and SOS1

The Kirsten rat sarcoma virus—son of sevenless 1(KRAS-SOS1)axis drives tumor growth preferentially in pancreatic,colon,and lung cancer.Now,KRAS G12C mutated tumors can be successfully treated with inhibitors that covalently block the cysteine of the switch II binding pocket of KRAS.However,the range of other KRAS mutations is not amenable to treatment and the G12C-directed agents Sotorasib and Adragrasib show a response rate of only approximately 40%,lasting for a mean period of 8 months.One approach to increase the efficacy of inhibitors is their inclusion into proteolysis-targeting chimeras(PROTACs),which degrade the proteins of interest and exhibit much higher antitumor activity through multiple cycles of activity.Accordingly,PROTACs have been developed based on KRAS-or SOS1-directed inhibitors coupled to either von Hippel-Lindau(VHL)or Cereblon(CRBN)ligands that invoke the proteasomal degradation.Several of these PROTACs show increased activity in vitro and in vivo compared to their cognate inhibitors but their toxicity in normal tissues is not clear.The CRBN PROTACs containing thalidomide derivatives cannot be tested in experimental animals.Resistance to such PROTACS arises through downregulation or inactivation of CRBN or factors of the functional VHL E3 ubiquitin ligase.Although highly active KRAS and SOS1 PROTACs have been formulated their clinical application remains difficult.

填充床流动求解与基于Chimera网格的分布式并行计算

填充床是一种常见的化学和生化反应器。由于内部结构的复杂性,填充床的局部流动求解一直是个颇有挑战性的问题。传统的填充床数值模拟是在CFD软件Fluent的平台上,采用非结构化网格求解。采用非结构网格求解存在网格生成困难,网格数目过多以及计算时间长等问题。Chimera网格的应用大大减少了填充床网格的数目及网格生成的难度。PVM分布式并行计算与Chimera网格的结合,使填充床的求解效率得到很大的提高。通过对两种方法在计算使用时间、内存使用量及计算结果的具体比较,阐述了Chimera网格结合PVM分布式并行计算在填充床流动求解中的优势。