Pancreatic cancer is one of the most aggressive cancers with a median survival time of less than 5 months,and conventional chemotherapeutics are the main treatment strategy.Poly(ADP-ribose)polymerase(PARP)inhibitors h...Pancreatic cancer is one of the most aggressive cancers with a median survival time of less than 5 months,and conventional chemotherapeutics are the main treatment strategy.Poly(ADP-ribose)polymerase(PARP)inhibitors have been recently approved for BRCA1/2-mutant pancreatic cancer,opening a new era for targeted therapy for this disease.However,most pancreatic cancer patients carry wild-type BRCA1/2 with resistance to PARP inhibitors.Here,we reported that mammalian target of rapamycin complex 2(mTORC2)kinase is overexpressed in pancreatic cancer tissues and promotes pancreatic cancer cell growth and invasion.Moreover,we found that knockdown of the mTORC2 obligate subunit Rictor sensitized pancreatic cancer cells to the PARP inhibitor olaparib.Mechanistically,we showed that mTORC2 positively regulates homologous recombination(HR)repair by modulating BRCA1 recruitment to DNA double-strand breaks(DSBs).In addition,we confirmed that combination treatment with the mTORC2 inhibitor PP242 and the PARP inhibitor olaparib synergistically inhibited pancreatic cancer growth in vivo.Thus,this study provides a novel target and strategy for optimizing PARP inhibitor efficiency in pancreatic cancers.展开更多
Inhibitor of DNA binding 2(Id2)can promote axonal regeneration after injury of the central nervous system.However,whether Id2 can promote axonal regeneration and functional recovery after peripheral nerve injury is cu...Inhibitor of DNA binding 2(Id2)can promote axonal regeneration after injury of the central nervous system.However,whether Id2 can promote axonal regeneration and functional recovery after peripheral nerve injury is currently unknown.In this study,we established a mouse model of bilateral sciatic nerve crush injury.Two weeks before injury,AAV9-Id2-3×Flag-GFP was injected stereotaxically into the bilateral ventral horn of lumbar spinal cord.Our results showed that Id2 was successfully delivered into spinal cord motor neurons projecting to the sciatic nerve,and the number of regenerated motor axons in the sciatic nerve distal to the crush site was increased at 2 weeks after injury,arriving at the tibial nerve and reinnervating a few endplates in the gastrocnemius muscle.By 1 month after injury,extensive neuromuscular reinnervation occurred.In addition,the amplitude of compound muscle action potentials of the gastrocnemius muscle was markedly recovered,and their latency was shortened.These findings suggest that Id2 can accelerate axonal regeneration,promote neuromuscular reinnervation,and enhance functional improvement following sciatic nerve injury.Therefore,elevating the level of Id2 in adult neurons may present a promising strategy for peripheral nerve repair following injury.The study was approved by the Experimental Animal Ethics Committee of Jinan University(approval No.20160302003)on March 2,2016.展开更多
BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breas...BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer.They are also effective for new and recurrent ovarian cancers that are BRCA-or homologous recombination deficiency(HRD)-positive.However,data on these mutations and PARPi use in the Middle East are limited.AIM To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.METHODS This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations,and 25 of 65 ovarian cancer patients tested for HRD.These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023.Data were summarized using descriptive statistics and compared using counts and percentages.Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.RESULTS Among the 472 breast cancer patients,12.1%underwent BRCA testing,and 38.5%of 65 ovarian cancer patients received HRD testing.Pathogenic mutations were found in 25.6%of the tested patients:26.3%breast cancers had germline BRCA(gBRCA)mutations and 24.0%ovarian cancers showed HRD.Notably,40.0%of gBRCA-positive breast cancers and 66.0%of HRD-positive ovarian cancers were Middle Eastern and Asian patients,respectively.PARPi treatment was used in 5(33.3%)gBRCA-positive breast cancer patients as first-line therapy(n=1;7-months progression-free),for maintenance(n=2;>15-months progression-free),or at later stages due to compliance issues(n=2).Four patients(66.6%)with HRD-positive ovarian cancer received PARPi and all remained progression-free.CONCLUSION Lower testing rates but higher BRCA mutations in breast cancer were found.Ethnicity reflected United Arab Emirates demographics,with breast cancer in Middle Eastern and ovarian cancer in Asian patients.展开更多
目的研究糖基转移酶抑制剂对原代培养大鼠肝细胞损伤中DNA损伤诱导蛋白2(DNA-damage inducible protein 2,DDI2)在mRNA水平表达的影响。方法原位胶原酶灌流法分离纯化大鼠原代肝细胞并培养,并用O-糖基化修饰抑制剂苄基-2-乙酰胺基-2-脱...目的研究糖基转移酶抑制剂对原代培养大鼠肝细胞损伤中DNA损伤诱导蛋白2(DNA-damage inducible protein 2,DDI2)在mRNA水平表达的影响。方法原位胶原酶灌流法分离纯化大鼠原代肝细胞并培养,并用O-糖基化修饰抑制剂苄基-2-乙酰胺基-2-脱氧-α-D-吡喃半乳糖苷(Benzyl-α-GalNAc)及N-糖基化修饰抑制剂衣霉素(tunicamycin,TM)处理细胞,Real time-PCR法测定DDI2 mRNA表达水平。结果衣霉素处理后的原代培养肝细胞DDI2表达上调,而Benzyl-α-GalNAc处理后的原代培养细胞DDI2表达有所下调。结论衣霉素及Benzyl-α-GalNAc在转录水平上分别上调和下调大鼠原代肝细胞DDI2的表达,从而参与肝细胞损伤的调节。展开更多
目的构建转录因子E2-2基因腺病毒载体,观测内皮祖细胞(endothelial progenitor cells,EPCs)过表达E2-2基因对DNA结合抑制因子-1(inhibitor of DNA binding/differentiation,ID1)表达的影响。方法分离、培养并鉴定小鼠骨髓EPCs。RT-PCR...目的构建转录因子E2-2基因腺病毒载体,观测内皮祖细胞(endothelial progenitor cells,EPCs)过表达E2-2基因对DNA结合抑制因子-1(inhibitor of DNA binding/differentiation,ID1)表达的影响。方法分离、培养并鉴定小鼠骨髓EPCs。RT-PCR法扩增E2-2基因CDs全长DNA,克隆入载体pTG19-T后,亚克隆入腺病毒穿梭载体pAdTrack-CMV中,构建pAdTrack/E2-2重组载体,与pAdEasy-1骨架质粒同源重组形成重组病毒pAd/E2-2,经293细胞包装,获具高效感染力的重组pAd/E2-2病毒。将该病毒感染EPCs,倒置显微镜观测经感染的EPCs的GFP表达情况。CCK-8(cell count kit-8)法检测病毒pAd/E2-2对EPCs生长、增殖的影响。RT-PCR、Western blot分别检测经感染的EPCs中E2-2与ID1基因及其编码蛋白的表达情况,并予以定量分析。结果分离、培养并鉴定到小鼠骨髓EPCs。克隆到2013 bp的E2-2基因,并获得高效感染力的重组pAd/E2-2病毒。CCK-8法检测表明,与对照比较,过表达E2-2的EPCs的生长、增殖速度减慢,48h开始变得尤为明显(P<0.01);RT-PCR、Western blot及定量分析结果显示,E2-2能下调ID1的表达,与对照比较,差异具统计学意义(P<0.01)。结论分离、培养并鉴定小鼠骨髓EPCs,克隆出E2-2基因,证实E2-2能明显抑制EPCs的生长、增殖,并能下调ID1基因的表达。展开更多
AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma...AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis.展开更多
目的研究DNA结合抑制物2(inhibitor of DNA binding 2,Id2)在ApcΔ716/+小鼠肠道肿瘤发生中的作用。方法 Id2基因缺失的基因工程小鼠和肠道肿瘤模型ApcΔ716/+小鼠杂交后,统计ApcΔ716/+小鼠与ApcΔ716/+Id2-/-杂交小鼠小肠肠道肿瘤的...目的研究DNA结合抑制物2(inhibitor of DNA binding 2,Id2)在ApcΔ716/+小鼠肠道肿瘤发生中的作用。方法 Id2基因缺失的基因工程小鼠和肠道肿瘤模型ApcΔ716/+小鼠杂交后,统计ApcΔ716/+小鼠与ApcΔ716/+Id2-/-杂交小鼠小肠肠道肿瘤的数目及总负荷,观查其肠道肿瘤发生和发展的变化。结果与ApcΔ716/+Id2野生型小鼠比较,ApcΔ716/+Id2-/-杂交小鼠在4、8、12周龄时肠道肿瘤总数目与不同大小的肠道肿瘤数目明显减少,差异有统计学意义(P均<0.05)。结论 Id2的缺失能抑制ApcΔ716/+小鼠肠道肿瘤的发生,Id2在人类肠道肿瘤中可能发挥着促进肿瘤形成的作用。展开更多
基金This work was supported by the National Natural Science Foundation of China(81572408)the Program of Medical Innovation Team and Leading Medical Talents in Jiangsu Province(2017ZXKJQW09).
文摘Pancreatic cancer is one of the most aggressive cancers with a median survival time of less than 5 months,and conventional chemotherapeutics are the main treatment strategy.Poly(ADP-ribose)polymerase(PARP)inhibitors have been recently approved for BRCA1/2-mutant pancreatic cancer,opening a new era for targeted therapy for this disease.However,most pancreatic cancer patients carry wild-type BRCA1/2 with resistance to PARP inhibitors.Here,we reported that mammalian target of rapamycin complex 2(mTORC2)kinase is overexpressed in pancreatic cancer tissues and promotes pancreatic cancer cell growth and invasion.Moreover,we found that knockdown of the mTORC2 obligate subunit Rictor sensitized pancreatic cancer cells to the PARP inhibitor olaparib.Mechanistically,we showed that mTORC2 positively regulates homologous recombination(HR)repair by modulating BRCA1 recruitment to DNA double-strand breaks(DSBs).In addition,we confirmed that combination treatment with the mTORC2 inhibitor PP242 and the PARP inhibitor olaparib synergistically inhibited pancreatic cancer growth in vivo.Thus,this study provides a novel target and strategy for optimizing PARP inhibitor efficiency in pancreatic cancers.
基金This work was supported by the National Natural Science Foundation of China,Nos.82071369(to PY)and 81971198(to BZ)Guangdong grant‘Key Technologies for Treatment of Brain Disorders’of China,No.2018B030332001(to LZ and PY)+2 种基金Guangzhou Key Projects of Brain Science and Brain-Like Intelligence Technology,China,No.20200730090(to LZ)the Natural Science Foundation of Beijing of China,No.7192103(to BZ)the Clinical Innovation Research Program of Guangzhou Regenerative Medicine and Health Guangdong Laboratory of China,No.2018GZR0201006(to PY).
文摘Inhibitor of DNA binding 2(Id2)can promote axonal regeneration after injury of the central nervous system.However,whether Id2 can promote axonal regeneration and functional recovery after peripheral nerve injury is currently unknown.In this study,we established a mouse model of bilateral sciatic nerve crush injury.Two weeks before injury,AAV9-Id2-3×Flag-GFP was injected stereotaxically into the bilateral ventral horn of lumbar spinal cord.Our results showed that Id2 was successfully delivered into spinal cord motor neurons projecting to the sciatic nerve,and the number of regenerated motor axons in the sciatic nerve distal to the crush site was increased at 2 weeks after injury,arriving at the tibial nerve and reinnervating a few endplates in the gastrocnemius muscle.By 1 month after injury,extensive neuromuscular reinnervation occurred.In addition,the amplitude of compound muscle action potentials of the gastrocnemius muscle was markedly recovered,and their latency was shortened.These findings suggest that Id2 can accelerate axonal regeneration,promote neuromuscular reinnervation,and enhance functional improvement following sciatic nerve injury.Therefore,elevating the level of Id2 in adult neurons may present a promising strategy for peripheral nerve repair following injury.The study was approved by the Experimental Animal Ethics Committee of Jinan University(approval No.20160302003)on March 2,2016.
文摘BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer.They are also effective for new and recurrent ovarian cancers that are BRCA-or homologous recombination deficiency(HRD)-positive.However,data on these mutations and PARPi use in the Middle East are limited.AIM To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.METHODS This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations,and 25 of 65 ovarian cancer patients tested for HRD.These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023.Data were summarized using descriptive statistics and compared using counts and percentages.Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.RESULTS Among the 472 breast cancer patients,12.1%underwent BRCA testing,and 38.5%of 65 ovarian cancer patients received HRD testing.Pathogenic mutations were found in 25.6%of the tested patients:26.3%breast cancers had germline BRCA(gBRCA)mutations and 24.0%ovarian cancers showed HRD.Notably,40.0%of gBRCA-positive breast cancers and 66.0%of HRD-positive ovarian cancers were Middle Eastern and Asian patients,respectively.PARPi treatment was used in 5(33.3%)gBRCA-positive breast cancer patients as first-line therapy(n=1;7-months progression-free),for maintenance(n=2;>15-months progression-free),or at later stages due to compliance issues(n=2).Four patients(66.6%)with HRD-positive ovarian cancer received PARPi and all remained progression-free.CONCLUSION Lower testing rates but higher BRCA mutations in breast cancer were found.Ethnicity reflected United Arab Emirates demographics,with breast cancer in Middle Eastern and ovarian cancer in Asian patients.
基金Supported by A 2-year grant of the Greek Ministry of Health and Welfare,No.111K/56
文摘AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis.
文摘目的研究DNA结合抑制物2(inhibitor of DNA binding 2,Id2)在ApcΔ716/+小鼠肠道肿瘤发生中的作用。方法 Id2基因缺失的基因工程小鼠和肠道肿瘤模型ApcΔ716/+小鼠杂交后,统计ApcΔ716/+小鼠与ApcΔ716/+Id2-/-杂交小鼠小肠肠道肿瘤的数目及总负荷,观查其肠道肿瘤发生和发展的变化。结果与ApcΔ716/+Id2野生型小鼠比较,ApcΔ716/+Id2-/-杂交小鼠在4、8、12周龄时肠道肿瘤总数目与不同大小的肠道肿瘤数目明显减少,差异有统计学意义(P均<0.05)。结论 Id2的缺失能抑制ApcΔ716/+小鼠肠道肿瘤的发生,Id2在人类肠道肿瘤中可能发挥着促进肿瘤形成的作用。
