BACKGROUND Epidemiological studies have revealed a correlation between Alzheimer’s disease(AD)and type 2 diabetes mellitus(T2D).Insulin resistance in the brain is a common feature in patients with T2D and AD.KAT7 is ...BACKGROUND Epidemiological studies have revealed a correlation between Alzheimer’s disease(AD)and type 2 diabetes mellitus(T2D).Insulin resistance in the brain is a common feature in patients with T2D and AD.KAT7 is a histone acetyltransferase that participates in the modulation of various genes.AIM To determine the effects of KAT7 on insulin patients with AD.METHODS APPswe/PS1-dE9 double-transgenic and db/db mice were used to mimic AD and diabetes,respectively.An in vitro model of AD was established by Aβstimulation.Insulin resistance was induced by chronic stimulation with high insulin levels.The expression of microtubule-associated protein 2(MAP2)was assessed using immunofluorescence.The protein levels of MAP2,Aβ,dual-specificity tyrosine phosphorylation-regulated kinase-1A(DYRK1A),IRS-1,p-AKT,total AKT,p-GSK3β,total GSK3β,DYRK1A,and KAT7 were measured via western blotting.Accumulation of reactive oxygen species(ROS),malondialdehyde(MDA),and SOD activity was measured to determine cellular oxidative stress.Flow cytometry and CCK-8 assay were performed to evaluate neuronal cell death and proliferation,respectively.Relative RNA levels of KAT7 and DYRK1A were examined using quantitative PCR.A chromatin immunoprecipitation assay was conducted to detect H3K14ac in DYRK1A.RESULTS KAT7 expression was suppressed in the AD mice.Overexpression of KAT7 decreased Aβaccumulation and MAP2 expression in AD brains.KAT7 overexpression decreased ROS and MDA levels,elevated SOD activity in brain tissues and neurons,and simultaneously suppressed neuronal apoptosis.KAT7 upregulated levels of p-AKT and p-GSK3βto alleviate insulin resistance,along with elevated expression of DYRK1A.KAT7 depletion suppressed DYRK1A expression and impaired H3K14ac of DYRK1A.HMGN1 overexpression recovered DYRK1A levels and reversed insulin resistance caused by KAT7 depletion.CONCLUSION We determined that KAT7 overexpression recovered insulin sensitivity in AD by recruiting HMGN1 to enhance DYRK1A acetylation.Our findings suggest that KAT7 is a novel and promising therapeutic target for the resistance in AD.展开更多
目的探讨逆转录病毒介导的RNAi对乳腺癌细胞系MCF-7中EphA2表达的影响。方法构建重组的表达EphA2siRNA的逆转录病毒载体,将重组载体和空载体转染入MCF-7细胞中,筛选出稳定转染的单克隆细胞扩大培养,并用Westen blot检测EphA2蛋白的表达...目的探讨逆转录病毒介导的RNAi对乳腺癌细胞系MCF-7中EphA2表达的影响。方法构建重组的表达EphA2siRNA的逆转录病毒载体,将重组载体和空载体转染入MCF-7细胞中,筛选出稳定转染的单克隆细胞扩大培养,并用Westen blot检测EphA2蛋白的表达情况。结果 Western blot分析,与对照空载体及未转染细胞比较,重组逆转录病毒载体转染的MCF-7细胞中EphA2蛋白表达水平明显降低(P<0.05)。结论通过逆转录病毒载体介导的RNAi,能够抑制MCF-7细胞中EphA2的蛋白表达,为观察转染siRNA的逆转录病毒表达载体的乳腺癌细胞恶性生物学行为变化奠定了实验基础,为以EphA2为靶向的乳腺癌的基因治疗提供了新的思路和手段。展开更多
AIM:To examine the expression of downstream of tyrosine kinase(DOK)1-6 genes in normal and breast cancer tissue and correlated this with several clinicopathological and prognostic factors.METHODS:DOK1-6 m RNA extracti...AIM:To examine the expression of downstream of tyrosine kinase(DOK)1-6 genes in normal and breast cancer tissue and correlated this with several clinicopathological and prognostic factors.METHODS:DOK1-6 m RNA extraction and reverse transcription were performed on fresh frozen breast cancer tissue samples(n = 112) and normal background breast tissue(n = 31). Tissues were collected between 1991 and 1996 at two centres and all patients underwent mastectomy and ipsilateral axillary node dissection. All tissues were randomly numbered and the details were only made known after all analyses were completed. Transcript levels of expression were determined using real-time polymerase chain reaction and analyzed against TNM stage, tumour grade and clinical outcome over a 10-year follow-up period.RESULTS:DOK-2 and DOK-6 expression decreased with increasing TNM stage. DOK-6 expression decreased with increasing Nottingham Prognostic Index(NPI) [NPI-1 vs NPI-3(mean copy number 15.4 vs 0.22, 95%CI:2.7-27.6, P = 0.018) and NPI-2 vs NPI-3(mean copy number 7.6 vs 0.22, 95%CI:0.1-14.6, P = 0.048)]. After a median follow up period of 10 years, higherlevels of DOK-2 expression were found among patients who remained disease-free compared to those who developed local or distant recurrence(mean copy number 3.94 vs 0.0000096, 95%CI:1.0-6.85, P = 0.0091), and distant recurrence(mean copy number 3.94 vs 0.0025, 95%CI:1.0-6.84, P = 0.0092). Patients who remained disease-free had higher levels of DOK-6 expression compared to those who died from breast cancer.CONCLUSION:Decreasing expression levels of DOK-2 and DOK-6 with increased breast tumour progression supports the notion that DOK-2 and DOK-6 behave as tumour suppressors in human breast cancer.展开更多
基金Supported by Natural Science Foundation of Shandong Province,No.ZR2020MH147National Natural Science Foundation of China,No.82002343.
文摘BACKGROUND Epidemiological studies have revealed a correlation between Alzheimer’s disease(AD)and type 2 diabetes mellitus(T2D).Insulin resistance in the brain is a common feature in patients with T2D and AD.KAT7 is a histone acetyltransferase that participates in the modulation of various genes.AIM To determine the effects of KAT7 on insulin patients with AD.METHODS APPswe/PS1-dE9 double-transgenic and db/db mice were used to mimic AD and diabetes,respectively.An in vitro model of AD was established by Aβstimulation.Insulin resistance was induced by chronic stimulation with high insulin levels.The expression of microtubule-associated protein 2(MAP2)was assessed using immunofluorescence.The protein levels of MAP2,Aβ,dual-specificity tyrosine phosphorylation-regulated kinase-1A(DYRK1A),IRS-1,p-AKT,total AKT,p-GSK3β,total GSK3β,DYRK1A,and KAT7 were measured via western blotting.Accumulation of reactive oxygen species(ROS),malondialdehyde(MDA),and SOD activity was measured to determine cellular oxidative stress.Flow cytometry and CCK-8 assay were performed to evaluate neuronal cell death and proliferation,respectively.Relative RNA levels of KAT7 and DYRK1A were examined using quantitative PCR.A chromatin immunoprecipitation assay was conducted to detect H3K14ac in DYRK1A.RESULTS KAT7 expression was suppressed in the AD mice.Overexpression of KAT7 decreased Aβaccumulation and MAP2 expression in AD brains.KAT7 overexpression decreased ROS and MDA levels,elevated SOD activity in brain tissues and neurons,and simultaneously suppressed neuronal apoptosis.KAT7 upregulated levels of p-AKT and p-GSK3βto alleviate insulin resistance,along with elevated expression of DYRK1A.KAT7 depletion suppressed DYRK1A expression and impaired H3K14ac of DYRK1A.HMGN1 overexpression recovered DYRK1A levels and reversed insulin resistance caused by KAT7 depletion.CONCLUSION We determined that KAT7 overexpression recovered insulin sensitivity in AD by recruiting HMGN1 to enhance DYRK1A acetylation.Our findings suggest that KAT7 is a novel and promising therapeutic target for the resistance in AD.
文摘目的探讨逆转录病毒介导的RNAi对乳腺癌细胞系MCF-7中EphA2表达的影响。方法构建重组的表达EphA2siRNA的逆转录病毒载体,将重组载体和空载体转染入MCF-7细胞中,筛选出稳定转染的单克隆细胞扩大培养,并用Westen blot检测EphA2蛋白的表达情况。结果 Western blot分析,与对照空载体及未转染细胞比较,重组逆转录病毒载体转染的MCF-7细胞中EphA2蛋白表达水平明显降低(P<0.05)。结论通过逆转录病毒载体介导的RNAi,能够抑制MCF-7细胞中EphA2的蛋白表达,为观察转染siRNA的逆转录病毒表达载体的乳腺癌细胞恶性生物学行为变化奠定了实验基础,为以EphA2为靶向的乳腺癌的基因治疗提供了新的思路和手段。
文摘AIM:To examine the expression of downstream of tyrosine kinase(DOK)1-6 genes in normal and breast cancer tissue and correlated this with several clinicopathological and prognostic factors.METHODS:DOK1-6 m RNA extraction and reverse transcription were performed on fresh frozen breast cancer tissue samples(n = 112) and normal background breast tissue(n = 31). Tissues were collected between 1991 and 1996 at two centres and all patients underwent mastectomy and ipsilateral axillary node dissection. All tissues were randomly numbered and the details were only made known after all analyses were completed. Transcript levels of expression were determined using real-time polymerase chain reaction and analyzed against TNM stage, tumour grade and clinical outcome over a 10-year follow-up period.RESULTS:DOK-2 and DOK-6 expression decreased with increasing TNM stage. DOK-6 expression decreased with increasing Nottingham Prognostic Index(NPI) [NPI-1 vs NPI-3(mean copy number 15.4 vs 0.22, 95%CI:2.7-27.6, P = 0.018) and NPI-2 vs NPI-3(mean copy number 7.6 vs 0.22, 95%CI:0.1-14.6, P = 0.048)]. After a median follow up period of 10 years, higherlevels of DOK-2 expression were found among patients who remained disease-free compared to those who developed local or distant recurrence(mean copy number 3.94 vs 0.0000096, 95%CI:1.0-6.85, P = 0.0091), and distant recurrence(mean copy number 3.94 vs 0.0025, 95%CI:1.0-6.84, P = 0.0092). Patients who remained disease-free had higher levels of DOK-6 expression compared to those who died from breast cancer.CONCLUSION:Decreasing expression levels of DOK-2 and DOK-6 with increased breast tumour progression supports the notion that DOK-2 and DOK-6 behave as tumour suppressors in human breast cancer.
