Discovery of novel exceptionally potent and orally active c-MET PROTACs for the treatment of tumors with MET alterations

Various c-mesenchymal-to-epithelial transition (c-MET) inhibitors are effective in the treatment of non-small cell lung cancer; however, the inevitable drug resistance remains a challenge, limiting their clinical efficacy. Therefore, novel strategies targeting c-MET are urgently required. Herein, through rational structure optimization, we obtained novel exceptionally potent and orally active c-MET proteolysis targeting chimeras (PROTACs) namely D10 and D15 based on thalidomide and tepotinib. D10 and D15 inhibited cell growth with low nanomolar IC50 values and achieved picomolar DC50 values and >99% of maximum degradation (Dmax) in EBC-1 and Hs746T cells. Mechanistically, D10 and D15 dramatically induced cell apoptosis, G1 cell cycle arrest and inhibited cell migration and invasion. Notably, intraperitoneal administration of D10 and D15 significantly inhibited tumor growth in the EBC-1 xenograft model and oral administration of D15 induced approximately complete tumor suppression in the Hs746T xenograft model with well-tolerated dose-schedules. Furthermore, D10 and D15 exerted significant anti-tumor effect in cells with c-METY1230H and c-METD1228N mutations, which are resistant to tepotinib in clinic. These findings demonstrated that D10 and D15 could serve as candidates for the treatment of tumors with MET alterations.

Preparation of 4-sulfonylcalix6arene-modified cotton for uranium contamination removal / 中国辐射卫生

Objective To prepare 4-sulfonylcalix[6]arene-modified cotton fibers for adsorption and removal of uranium based on the specific complexation of calix[6]arene with uranium (VI). Methods Chemical grafting was used for the modification of cotton, which reacted with α-bromoisobutyryl bromide, glycidyl methacrylate, and 4-sulfonylcalix[6]arene. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (FTIR) were used to characterize the structure of 4-sulfonylcalix[6]arene-modified cotton (Cotton S-C[6]a). A Franz diffusion cell was used to simulate uranium-contaminated skin. Laser fluorimetry was used to determine the uranium content. Results SEM, XPS, and FTIR showed that cotton fibers were successfully grafted with 4-sulfonylcalix[6]arene. The optimal conditions of Cotton S-C[6]a for the adsorption of uranium (VI) was pH 4.0, duration of 20 min, and 20 mg of adsorbent. The adsorption process fitted well with pseudo-secondary-order kinetics. The uranium removal efficiency of Cotton S-C[6]a was up to 78.46% in aqueous solution and 81.72% on skin. Conclusion The synthesized Cotton S-C[6]a is highly efficient in the removal of uranium (VI) in solution and on contaminated skin.

Role of complement in radiation-induced lung injury / 中国辐射卫生

@#<b>Objective</b> To investigate the role of complement in radiation-induced lung injury in mice after chest irradiation with ⁶⁰Co γ-rays at a single dose of 20 Gy. <b>Methods</b> C57BL/6 mice underwent chest irradiation with ⁶⁰Co γ-rays at a single dose of 20 Gy, followed by observation for the inflammatory reaction of the lung tissue in the early stage (within 15 d) and pulmonary fibrosis in the later stage (30 and 180 d). Enzyme-linked immunosorbent assay was used to measure the levels of C2, C3a, C4, and C5b-9 in the lung tissues at 1, 3, 7, 15, 30, and 180 d after irradiation. The expression of complement mRNA in BEAS-2B cells after irradiation was determined using RT-PCR. <b>Results</b> Radiation-induced lung injury in micepresented as inflammatory response in the early stage and fibrosis in the late stage. Complement C2, C4, and C5b-9 complexes were increased in the early period (3 or 7 d) after irradiation (<i>P</i> < 0.05), which might be associated with the inflammatory response induced by irradiation. During 3 to 180 d, complement C3a was significantly higher in the irradiated mice than in the control mice, suggesting a close relationship between C3a and radiation-induced lung injury. The irradiated cells showed increased mRNA expression of C2 and C3, with no changes in the mRNA levels of C4 and C5. <b>Conclusion</b> Different complement proteins have varying responses to radiation-induced lung injury, among which C3a is closely related to radiation-induced lung injury, suggesting that regulating C3a and its receptors may be a new way to prevent and treat radiation-induced lung injury.

Antigen presentation and T cell activation by dendritic cells in radiation damage / 中国辐射卫生

@#<b>Objective</b> To explore dendritic cells (DCs)-mediated antigen presentation for radiation-injured cells by using the <i>in vitro</i> cell co-culture technology to simulate the <i>in vivo </i>microenvironment of the lung tissue. <b>Methods</b> ⁶⁰Co γ-irradiated mouse lung epithelial cells (MLE-12) were cultured with bone marrow-derived DCs and/or splenic T lymphocytes for 48 hours. Flow cytometry was used to measure the expression levels of costimulatory molecules (CD80/86) and antigenic peptide recognition complexes (the major histocompatibility complex [MHC] class Ⅰ/Ⅱ) on DCs and T cell activation markers (CD69/28/152) as well as the numbers of CD4⁺ and CD8⁺ T cells. <b>Results</b> ⁶⁰Co γ irradiation significantly increased the apoptosis rate of MLE-12 cells in a dose-dependent manner, and significantly stimulated the expression of CD80/86 and MHC Ⅱ on DCs, without direct activation of T cells. After γ (6 Gy)-irradiated MLE-12 cells were co-cultured with DCs and T lymphocytes for 48 h, there were significant increases in the expression of CD69 and CD28 on T cells, the numbers of CD4⁺ and CD8⁺ T cells, and the expression of CD86 and MHC I on DCs, as compared with the control groups. <b>Conclusion</b> Radiation-injured cells can stimulate antigen presentation by DCs and activate T cells.

Interfering with glutathione S-transferase P1 induces lung cell damage under irradiation conditions / 中华放射肿瘤学杂志

Objective To investigate the association and mechanism between glutathione S-transferase P1(GSTP1) and radiation-induced lung injury.Methods Two effective GSTP1 siRNAs were designed and synthesized.The normal lung epithelial cell line BEAS-2B cells were transfected with GSTP1 siRNA (experimental group,siRNA-1,siRNA-2) and negative control siRNA (negative control group,NC).Western blot was performed to detect the expression levels of GSTP1 protein and EMT-related proteins.CDNB was adopted to evaluate the activity of GSTs.DCFH-DA probe was used for incubation.Flow cytometry was conducted to detect the median fluorescence intensity (MFI) and cellular apoptosis.Annexin-v/PI staining was utilized for incubation.MTT assay was performed to measure the proliferation of BEAS-2B,and the growth curve was drawn based on the results.Results After radiation,compared with the NC group,the ROS level and MFI were significantly higher in experimental group (6774.66±399.60 vs.8759.00±256.96 vs.9967.67±735.11,P＜0.05).In the experimental group,the percentage of cellular apoptosis was remarkably higher than that in the NC group (12.3± 1.16 vs.17.38± 1.65 vs.22.88± 1.20,P＜0.05).MTT assay demonstrated that the OD values in the experimental group were significantly lower than that in the NC group everyday.Further more,the level of EMT process is higher in the experimental group.Conclusions Interfering with the GSTP1 expression in lung epithelial cells can increase the intracellular ROS level,increase the percentage of cellular apoptosis,and reduce the cell proliferation rate following γ-radiation.Besides,it can also promote the epithelial mesenchymal transition in lung epithelial cells.The down-regulation of GSTP1 protein expression level probably aggravates the radiationinduced lung cell injury and promotes the epithelial mesenchymal transition.

Roles of PIF1 helicase in cell cycle arrest induced by ionizing radiation / 军事医学

Objective To observe the effect of PIF1 knockdown on cell growth and cell cycle arrest induced by ionizing radiation.Methods HeLa cell lines that consistently down-regulated PIF1 were prepared by the lentivirus granules interfering technology and confirmed by real-time PCR and Western blotting.The effect of down-regulation of PIF1 on cell growth and cell cycle arrest induced by ionizing radiation was evaluated by cell counting and flow cytometry.Results HeLa cell lines consistently down-regulating PIF1 were established.The growth of HeLa that down-regulated PIF1 was inhibited greatly after 4 Gy of γ-ray irradiation.There was little cell proliferation until the 5th day post 4 Gy γ-ray.Moreover, the S phase block and G2/M phase block of PIF1 knock-downed cell lines were significantly delayed after 8 Gy γ-ray irradiation.Conclusion Knockdown of PIF1 can significantly enhance the radiation sensitivity and delayes the S phase block and G 2 /M phase block induced by ionizing radiation.

Role of Hes1 in malignant transformation of human bronchial epithelial cells induced by tobacco / 中国病理生理杂志

AIM: To investigate the role of transcription factor hairy and enhancer of split 1 (Hes1) in the malignant transformation of human bronchial epithelial cell line BEP2D induced by tobacco.METHODS: The BEP2D cells were chronically exposed to cigarette smoke condensate (CSC) at 1 cigarette per L until the 70th generation.The phenotype of malignant transformation of the cells induced by CSC was detected by soft agar clony formation assay.RT-PCR and Western blot were used to determined the expression of Hes1 at mRNA and protein levels in each generation of the cells.The proliferation and apoptosis of the BEP2D cells exposed to CSC were analyzed with the methods of MTT assay, flow cytometry and cell colony formation assay after treatment with Notch pathway bloker DAPT or liposome transfection with Hes1-siRNA.The expression of Hes1 in the peripheral small airway tissues of the smoking rats was evaluated by immunohistochemical staining.The expression of Hes1 in non-small-cell lung cancer and normal airway tissues was also detected by the methods of immunohistochemistry and RT-PCR.RESULTS: The BEP2D cells in the 70th generation had a malignant transformation phenotype.The expression of Hes1 in the BEP2D cells exposed to CSC for different time showed an increa-sing trend.DAPT and liposome transfection with Hes1-siRNA down-regulated the expression of Hes1, inhibited the cell proliferation and induced cell apoptosis.The expression of Hes1 in the airway mucosa of the rats exposed to cigarette smoke for 1 month and 6 months was significantly higher than that in control group.Cigarette smoking induced the expression of Hes1 in lung cancer and normal airway tissues.CONCLUSION: Hes1 may be involved in smoking-induced lung cancer by promoting the imbalance between apoptosis and proliferation.

The eukaryotic expression,intracellular location and functions of human CAP1 / 西安交通大学学报(医学版)

Objective To construct the recombinant eukaryotic expression plasmids of human adenylyl cyclase-associated protein 1 (CAP1)and to explore its intracellular location and functions.Methods By using Hela cDNA as the template,the cDNAs encoding CAP1 was amplified by PCR and inserted into pCMV-Myc vector to construct the recombinant plasmid.The recombinant plasmid was transfected into 293 cells using lipofectamine 2000.The protein expression and the intracellular location of the inserted gene were confirmed by Western blotting and immunofluorescence,respectively.Scratch-repair experiment was used to detect the cancer cells’ migration ability.Results The recombinant eukaryotic expression plasmid of human CAP1 was successfully constructed and transfected into eukaryote cells.The recombinant plasmid was successfully expressed in eukaryote cells.CAP1 was located in the cytoplasm.The results of scratch-repair experiment showed that the overexpression of CAP1 could significantly inhibit the cells’ migration.Conclusion CAP1 recombinant plasmid was successfully expressed in eukaryotic cells.CAP1 protein was located in the cytoplasm.The overexpression of CAP1 inhibited cell migration. The present study provides important experimental evidence for further study on CAP1.

Effects of moxa smoke with different concentrations on expression of SOD and MDA in lung and serum of rats / 中国针灸

<p><b>OBJECTIVE</b>To observe the effects of intervention of moxa smoke with different concentrations on superoxide dismutase (SOD) and malondialdehyde (MDA) in serum and lung of male rats, so as to explore the safety concentration of moxa smoke.</p><p><b>METHODS</b>A total of 32 Wistar male rats were randomly divided into a control group, a low-concentration group, a moderate-concentration group and a high-concentration group, 8 rats in each one. All the rats were exposed in the full-automatic toxicant exposure cabinet, and the overshadow of moxa smoke was set at 0%, 10%, 40% and 70%, respectively. Each rat was exposed for 20 min per day. After 26 weeks, the activities of SOD and content of MDA in serum, lung organ and bronchoalveolar lavage fluid were tested.</p><p><b>RESULTS</b>Compared with the control group, the activities of serum SOD in the high-concentration group were reduced (P< 0. 05), but those in the low-concentration group and moderate-concentration group were not significantly different (both P>0. 05). Compared with the control group, the content of serum MDA in the low-concentration group, moderate-concentration group and high-concentration group was increased insignificantly (all P>0. 05). There were no significant differences regarding activities of SOD and content of MDA in lung organ and bronchoalveolar lavage fluid among each moxa smoke group (all P>0. 05).</p><p><b>CONCLUSION</b>There is no obvious toxic reaction in the low-concentration group and moderate-concentration group; in the high-concentration group the antioxidant ability is damaged due to long-term exposure.</p>

Clearance of insoluble depleted uranium particles in lungs by citric acid and ambroxol / 军事医学

Objective To investigate the effect of citric acid and ambroxol on clearing insoluble particles of depleted uranium in rat lungs by establishing a tracheal perfusion model.Methods One hundred and fifty male Wistar rats were randomly divided into model exposure group, normal control group(NC group), depleted uranium exposure group(DU), citric acid treatment group( CA) , ambroxol treatment group( AM) and citric acid+ambroxol treatment group( CA+AM) . The rats were sacrificed on 7, 15 and 30 days.Uranium content in the lungs was detected by microwave digestion method, pathological changes in the lungs were observed, and inflammatory factors of lung homogenates were detected.Results Compared to DU control group, the intrapulmonary uranium deposit amount in experimental groups was significantly reduced on 7 and 15 days (P<0.05).HE stained lung tissue showed that the pathological changes in treatment groups were less significant than in DU control group.The level of IL-1α,IL-1β,and IL-2 was significantly lower than in DU control, but the level of MCP-1 and MIP-1 was observably higher.Conclusion Citric acid and ambroxol can evidently improve the clear-ance of lung uranium and reduce damnification of lung tissues.Drug treatment can reduce the level of pulmonary inflamma-tory cytokines alleviate the chronic inflammation in the lungs, and enhance the capacity of macrophage to recruitment.

Research of herb components on scavenging harmful components and reducing cytotoxicity of cigarette smoke / 中国中药杂志

<p><b>OBJECTIVE</b>To study the in vitro effect of herb components on scavenging harmful components of cigarette smoke such as radicals, polycyclic aromatic hydrocarbons, nitrosamines in vitro, and its reducing effect on cytotoxicity of cigarette smoke.</p><p><b>METHOD</b>spectrophotometry was used to examine the scavenging effect of herb components on DPPH free radicals, superoxide anion radical, and hydroxyl radical, and the results were compared with the anti-oxidation of ascorbic acid. Fluorescence spectroscopy was used to examine the scavenging effect of herb components on polycyclic aromatic hydrocarbons. UV spectrophotometry was used to examine the scavenging effect of herb components on volatile nitrosamines. MTT assay was used to examine cytotoxicity of cigarette smoke.</p><p><b>RESULT</b>All the herb components showed a certain scavenging effect on DPPH free radicals, superoxide anion radical, hydroxyl radical, polycyclic aromatic hydrocarbons and volatile nitrosamines, espacially the ginkgo biloba extract (GBE), flavonoids of glycyrrhiza, procyanidine, total saponins in ophiopogonin, total saponins of astragalus and epimediun flavonoids. After these six herb components were added to cigarette, the cytotoxicity of cigarette smoke on BEP2D cells was remarkably reduced, by increasing cell survival fraction (SF, %) and mean lethal dose (DML).</p><p><b>CONCLUSION</b>The herb components can scavenge harmful components of cigarette smoke such as radicals, polycyclic aromatic hydrocarbons and nitrosamines, which reduce the damage of cigarette smoke on human being.</p>

Effect of S-band microwave long-term intermittent irradiation on endocrine fuction in rats / 中华放射医学与防护杂志

Objective To observe the effect of S-band micro-wave long-term intermittent irradiation on endocrine function in rats.Methods A total of 192 rats (male and female) were randomly divided into the sham-irradiation (normal control) groups and the irradiation groups.The irradiation groups were exposed with micro-wave at 3 dosages of 4,10 and 20 mW/cm2 for 6 min twice a week for 12 weeks,while no administration was given to control group.The endocrine parameters in blood serum were examined by radioimmunoassay at 4,8,12 week during irradiation and 4 week post-irradiation.Results After the irradiation of S-band microwave,parts of the endocrine parameters changed.T3 in famale rats decreased at first and then increased,especially in 10 mW/cm2 group at 8 and 12 week,20 mW/cm2 group at 4 and 12week(t =-2.586,-2.642,-5.075,-4.365,P <0.05).FT3 in famale rats had the similar trend asT3,significantly lower in 4 and 10 mW/cm2 groups than that in the control group at 4 week (t = 2.275,2.510,P <0.05),then increased,especially in three irradiation groups at 12 week (t =-2.636,-2.851,-5.240,P < 0.05).TSH decreased at 4 week,especially in 10 mW/cm2 group (t = 2.300,P < 0.05) ; and then increased in the irradiation groups at 20 mW/cm2 at 8 and 12 week (t =-2.838,-3.651,P <0.05).COR and ACTH in male rats showed changes in volatility,in which the 4,10 and 20 mW/cm2 groups at 8 week increased significantly (t =-2.772,-2.234,-2.505,P < 0.05),while 20 mW/cm2 group at 12 week decreased significantly (t=3.067,P < 0.05).E2 in female rats was slightly lower in irradiation groups at 4 week than the control group,then increased,especially in 10 mW/cm2 group at 8 week,three irradiation groups at 12 week (t =-2.322,-3.179,-2.655,-4.716,P < 0.05),and returned to the normal at 4 week post-irradiation,significantly lower in 4 mW/cm2 group than that in the control group (t = 2.250,P < 0.05).T in male rats increased first and then decreased,especially in 10 mW/cm2 group at 8 week(t =-2.435,P < 0.05).After exposure the above indexes restored to some extent.Conclusions The long-term intermittent irradiation of S-band microwave can cause adverse effects on the endocrine function of rats.

Effect of the phagocytosis function on NR8383 ceil exposed to cigarette smoke extracts / 中华微生物学和免疫学杂志

Objective To investigate the phagocytosis function of cigarette smoke extracts (CSE)on the NR8383 cells. Methods The concentration of CSE and the optimal time was defined by cell counting kit-8 assay, Annexin V/PI cell apoptosis assay and CFSE cell proliferation assay. The cell was gained after exposed to the different concentration of CSE for 24 h and mixed with fluorescein-labeled Escherichia coli in 37℃ for 2 h. The fluorescence intensity was used to assay the phagocytosis function of NR8383 cells.Results The phagocytosis function of NR8383 cells may be changed by the concentration of CSE. In the concentration of 100 μg/ml, the phagocytosis function of NR8383 was enhanced 0.5 times than the normal cell when NR8383 cell was exposed to CSE, and the specific activity is the highest. When NR8383 cells were exposed to CSE and LPS, the phagocytosis function of NR8383 cells was enhanced 2 times than the normal cell. In the concentration of 200 μg/ml, the phagocytosis function of NR8383 cells was damaged, the rate of apoptosis is the 54. 1%. Conclusion Low concentration of CSE enhanced the phagocytosis function of NR8383 cells, but high concentration of CSE damaged the phagocytosis function of NR8383 cells. This study reveals a new role of CSE as an activator of macrophage function.

Oxidative damage of BEAS-2B cells induced by depleted uranium and protection by DMSO / 中华放射医学与防护杂志

Objective To observe the oxidative damage in human bronchial epithelial cells(BEAS-2B) induced by depleted uranium(DU)and protection of DMSO.Methods The measurement of extracellular superoxide anions(O2-·)was based on the reduction of ferricytochrome C.Quantitative analysis of extracellular hydrogen peroxides(H2O2)was used by the horseradish peroxidase-dependent oxidation of phenol red.The determination of extracellular hydroxyl radicals(·OH)was based on discoloration of safranine T.Ethidium bromide and 2,7'-dichlorofluorescein,fluorescent products of the membrane-permeable dyes-hydroethineand 2,7'-dichloroflurescin diacetate were used to monitor the intracellular production of O2-·and H2O2 by fluorometric method.The enzyme activity of SOD and GSH were measured by chemiluminescence and spectrophotometric method,respectively.Results The ROS production,including H2O2,O2-·and·OH,increased remarkably which induced by DU in BEAs-2B cells.The enzyme activity of SOD and GSH was descended remarkedly.These changes could be effectively inhibited by 0.5% of DMSO.Conclusions DU causes oxidative damage to BEAS-2B cells.Through removing active oxygen,DMSO can inhibit oxidative damage of DU.

Comparison of Suspension Array and EnzymE-Linked Immunosorbent Assay Methods for Detection of Three Kinds of Veterinary Drug Residues / 分析化学

A novel suspension array technology was established for the detection of three kinds of veterinary drug residues: chloramphenicol, clenbuterol and 17-β-estradiol. The three conjugates in which veterinary drugs coupled with BSA were immobilized on the solid carrier of the suspension microarray-polystyrene fluorescent microspheres/beads as detective probes. Indirect competitive technology was employed. Competitive reactions between the veterinary drugs in the aqueous phase and the veterinary drugs-BSA conjugates on the beads for coupling with their complimentary specific biotinylated monoclonal antibodies were carried out. And then, straptavidin-phycoerythrin was added for coupling and the fluorescent signals were captured. Afterwards the detective standard curves were plotted. The regular ELISA standard curves of the three veterinary drugs were also plotted. Comparison between suspension array and regular enzymE-linked immunosorbent assay(ELISA) was in the respects of the detective technology, the detection limits, the detective ranges, the samples detection and the multi-analysis. Suspension array technology is distinct advantageous except for specificity. There was well consistent performance between the two methods. The high-throughput suspension array provides a novel method for multi-analysis of veterinary drugs with simple operation, sensitive, rapid and low costing.

Distribution of uranium in rata inhaled with depleted uranium aerosols / 中华放射医学与防护杂志

Objective To investigate the distribution of uranium in rats after inhalation with depleted uranium aerosols. Methods The depleted uranium aerosols were inhaled by Wistar rats. At 30, 90, 180, 270, 360, and 540 d after inhalation, the rata were sacrificed and tissue samples were collected. The contents of uranium in lung, kidney, liver, heart, brain, thighbone, spleen and thymus were measured by laser time-dependent spectroscopy analysis. Resulits The uranium contents of lung increased in the high-dosc and low-dose groups [(499833.3 ± 14214.8) ng/g and (25 424.0 ± 6193.4)ng/g, respectively] after inhalation, and significantly differed from the control (28.8 ± 13.9)ng/g, (P < 0.05).At 30 d after inhalation, the contents of uranium in lung, kidney and thighbone were higher than those of control, and then decreased time-dependently. At 60 d, the contents of uranium in liver, heart, brain, spleen and thymus were higher than those of control. Curve of the eontenta were biphasie, whieh went up first, reached at peak value and then went down. The contents of uranium were high in lung, thighbone, brain and thymus. Conclusions After inhalation of depleted uranium aerosols, lung and thighbone are the primary reservoirs for uranium redistributed, and accumulations in brain and thymus suggest other two organs for unanticipated injury by depleted uranium.

Antagonism of DMSO against Genotoxicity of Cooking Oil Fume Condensate to BEAS-2B Cell / 环境与健康杂志

Objective To study the antagonism of DMSO against the toxicity of cooking oil fume condensation to BEAS-2B cell.Methods The comet assay,micronucleus test and multinucleated cells test were used to research the genotoxicity induced by cooking oil fume condensation(COFC)and the antagonism of DMSO.Results COFC induced DNA broken,the tail area,rate of comet occurrence,tail length,tail moment,olive tailmoment increased significantly,the frequencies of micronucleus and multinucleated cells were significantly increased and the damage of cells could be inhibited effectively by DMSO.Conclusion The antagonistic effects of DMSO on the toxicity of COFC was significant in BEAS-2B cell.

STUDY ON LIVER PROTECTION, TUMOR INHIBITION AND IMMUNE REGULATION OF NANO RED ELEMENTAL SELENIUM / 营养学报

Objective: To study the effects of nano red elemental selenium on liver protection, tumor inhibition and immune regulation. [WT5FZ]Methods: [WT5BZ]Models of acute liver injury induced by CCl 4, S 180 tumor growth and immune regulation were used. Results: Nano red elemental selenium could increase blood and liver Se contents, inhibit the increase of liver MDA and serum AST induced by CCl 4, decrease tumor weight and increase phagocytic ratio and NK cell activity in S 180 bearing mice, increase immune activities in normal mice. All these improvements were statistically significant (P