BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-posi...BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-positive carrier status or cirrhosis to liver cancer are unknown.The epigenetic modification of DNA hydroxymethylation is critical in tumor development.Further,5-hydroxymethylcytosine(5hmC)is an important base for DNA demethylation and epigenetic regulation.It is also involved in the assembly of chromosomes and the regulation of gene expression.However,the mechanism of action of 5hmC in HBsAgpositive carriers or patients with cirrhosis who develop liver cancer has not been fully elucidated.AIM To investigate the possible epigenetic mechanism of HBsAg-positive carriers and hepatocellular carcinoma(HCC)progression from cirrhosis.METHODS Forty HBsAg-positive carriers,forty patients with liver cirrhosis,and forty patients with liver cancer admitted to the First People's Hospital of Yongkang between March 2020 and November 2021 were selected as participants.Free DNA was extracted using a cf-DNA kit.cfDNA was extracted by 5hmC DNA sequencing for principal component analysis,the expression profiles of the three groups of samples were detected,and the differentially expressed genes(DEGs)modified by hydroxymethylation were screened.Bioinformatic analysis was used to enrich DEGs,such as in biological pathways.RESULTS A total of 16455 hydroxymethylated genes were identified.Sequencing results showed that 32 genes had significant 5hmC modification differences between HBsAg carriers and liver cancer patients,of which 30 were upregulated and 2 downregulated in patients with HCC compared with HBsAg-positive carriers.Significant 5hmC modification differences between liver cirrhosis and liver cancer patients were identified in 20 genes,of which 17 were upregulated and 3 were downregulated in patients with HCC compared with those with cirrhosis.These genes may have potential loci that are undiscovered or unelucidated,which contribute to the development and progression of liver cancer.Analysis of gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes showed that the major signaling pathways involved in the differential genes were biliary secretion and insulin secretion.The analysis of protein interactions showed that the important genes in the protein-protein interaction network were phosphoenolpyruvate carboxykinase and solute carrier family 2.CONCLUSION The occurrence and development of liver cancer involves multiple genes and pathways,which may be potential targets for preventing hepatitis B carriers from developing liver cancer.展开更多
BACKGROUND Most gastric cancer(GC)patients are diagnosed at middle or late stage because the symptoms in early stage are obscure,which causes higher mortality rates of GC.Helicobacter pylori(H.pylori)was identified as...BACKGROUND Most gastric cancer(GC)patients are diagnosed at middle or late stage because the symptoms in early stage are obscure,which causes higher mortality rates of GC.Helicobacter pylori(H.pylori)was identified as a class I carcinogen and leads to aberrant DNA methylation/hydroxymethylation.5-hydroxymethylcytosine(5-hmC)plays complex roles in gene regulation of tumorigenesis and can be considered as an activating epigenetic mark of hydroxymethylation.AIM To explore the association between 5-hmC levels and the progression and prognosis of GC patients with or without H.pylori infection.METHODS A retrospective cohort study was conducted to estimate the predicted value of 5-hmC level in the progression and prognosis of GC patients with different H.pylori infection status.A total of 144 GC patients were recruited.RESULTS The levels of 5-hmC were significantly decreased in tumor tissues(0.076±0.048)compared with the matched control tissues(0.110±0.057,P=0.001).A high level of 5-hmC was an independent significant favorable predictor of overall survival in GC patients(hazard ratio=0.61,95% confidence interval:0.38-0.98,P=0.040),the H.pylori-negative GC subgroup(hazard ratio=0.30,95% confidence interval:0.13-0.68,P=0.004)and the GC patients with TNM stage Ⅰ or Ⅱ(hazard ratio=0.32,95% confidence interval:0.13-0.77,P=0.011).CONCLUSION Increased 5-hmC is a favorable prognostic factor in GC,especially for H.pylori-negative subgroups.展开更多
Robust and clinically convenient biomarkers for cancer diagnosis,early detection,and prognosis have great potential to improve patient survival and are the key to precision medicine.The advent of next-generation seque...Robust and clinically convenient biomarkers for cancer diagnosis,early detection,and prognosis have great potential to improve patient survival and are the key to precision medicine.The advent of next-generation sequencing technologies enables a more sensitive and comprehensive profiling of genetic and epigenetic information in tumor-derived materials.Researchers are now able to monitor the dynamics of tumorigenesis in new dimensions,such as using circulating cell-free DNA(cfDNA)and tumor DNA(ctDNA).Mutation-based assays in liquid biopsy cannot always provide consistent results across studies due partly to intra-and inter-tumoral heterogeneity as well as technical limitations.In contrast,epigenetic analysis of patient-derived cfDNA is a promising alternative,especially for early detection and disease surveillance,because epigenetic modifications are tissue-specific and reflect the dynamic process of cancer progression.Therefore,cfDNA-based epigenetic assays are emerging to be a highly sensitive,minimally invasive tool for cancer diagnosis and prognosis with great potential in future precise care of cancer patients.The major obstacle for applying epigenetic analysis of cfDNA,however,has been the lack of enabling techniques with high sensitivity and technical robustness.In this review,we summarized the advances in epigenome-wide profiling of 5-hydroxymethyl-cytosine(5hmC)in cfDNA,focusing on the detection approaches and potential role as biomarkers in different cancer types.展开更多
Background: DNA hydroxymethylation refers to a chemical modification process in which 5-methylcytosine (5mC) is catalyzed to 5-hydroxymethylcytosine (5hmC) by ten-eleven translocation (TET) family proteins. Rec...Background: DNA hydroxymethylation refers to a chemical modification process in which 5-methylcytosine (5mC) is catalyzed to 5-hydroxymethylcytosine (5hmC) by ten-eleven translocation (TET) family proteins. Recent studies have revealed that aberrant TETs expression or 5hmC level may play important roles in the occurrence and development of various pathological and physiological processes including cancer and aging. This study aimed to explore the relation between aberrant DNA hydroxymethylation with skin photoaging and to investigate the levels of TETs, 5mC, and 5hmC expression 24 h after 40 mJ/cm^2 and 80 mJ/cm^2 doses of ultraviolet B (UVB) irradiation to HaCaT cells. Methods: To explore whether aberrant DNA hydroxymethylation is also related to skin photoaging, 40 mJ/cm^2 and 80 mJ/cm^2 doses of UVB were chosen to treat keratinocytes (HaCaT cells). After 24 h of UVB irradiation, 5mC and 5hmC levels were determined by immunohistochemistry (IHC) and immunofluorescence (IF), and at the same time, the expression levels of matrix metalloproteinase 1 (MMP-1) and TETs were assessed by reverse transcription-polymerase chain reaction or Western blot analysis. Results: After 40 mJ/cm^2 and 80 mJ/cm^2 doses of UVB exposure, both IHC and IF results showed that 5hmC levels increased significantly, while the 5mC levels did not exhibit significant changes in HaCaT cells, compared with HaCat cells without UVB exposure. Moreover, compared with HaCat cells without UVB exposure, the levels ofTET1, TET2, and TET3 mRNA and protein expression were significantly upregulated (mRNA: P = 0.0022 and 0.0043 for TET1; all P 〈 0.0001 for TET2; all P = 0.0006 for TET3; protein: P = 0.0012 and 0.0006 tbr TET 1 ; all P = 0.0022 for TET2; and all P = 0.0002 for TET3), and the levels of MMP- 1 mRNA expression increased dose dependently in 40 mJ/cm^2 and 80 mJ/cm^2 UVB-irradiated groups. Conclusion: UVB radiation could cause increased 5hmC and TET expression, which might become a novel biomarker in UVB-related skin aging.展开更多
Although DNA 5-hydroxymethylcytosine(5 hmC)is recognized as an important epigenetic mark in cancer,its precise role in lymph node metastasis remains elusive.In this study,we investigated how 5 hmC associates with lymp...Although DNA 5-hydroxymethylcytosine(5 hmC)is recognized as an important epigenetic mark in cancer,its precise role in lymph node metastasis remains elusive.In this study,we investigated how 5 hmC associates with lymph node metastasis in breast cancer.Accompanying with high expression of TET1 and TET2 proteins,large numbers of genes in the metastasis-positive primary tumors exhibit higher 5 hmC levels than those in the metastasis-negative primary tumors.In contrast,the TET protein expression and DNA 5 hmC decrease significantly within the metastatic lesions in the lymph nodes compared to those in their matched primary tumors.Through genomewide analysis of 8 sets of primary tumors,we identified 100 high-confidence metastasis-associated5 hmC signatures,and it is found that increased levels of DNA 5 hmC and gene expression of MAP7 D1 associate with high risk of lymph node metastasis.Furthermore,we demonstrate that MAP7 D1,regulated by TET1,promotes tumor growth and metastasis.In conclusion,the dynamic5 hmC profiles during lymph node metastasis suggest a link between DNA 5 hmC and lymph node metastasis.Meanwhile,the role of MAP7 D1 in breast cancer progression suggests that the metastasis-associated 5 hmC signatures are potential biomarkers to predict the risk for lymph node metastasis,which may serve as diagnostic and therapeutic targets for metastatic breast cancer.展开更多
目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的s...目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的shRNA(shRNA-METTL5)转染TNBC细胞后,用CCK-8、集落形成、伤口愈合以及Transwell实验分别检测细胞增殖活性、迁移与侵袭,Western blot检测Wnt/β-catenin信号关键蛋白的表达。构建异种移植瘤模型,验证敲降METTL5对TNBC细胞在体内生长以及Wnt/β-catenin信号活性的影响。结果METTL5在TNBC肿瘤组织和细胞系中表达上调(P<0.01)。敲降METTL5可抑制TNBC细胞的增殖、迁移和侵袭并降低了Wnt/β-catenin信号分子β-catenin、细胞周期蛋白(Cyclin)D1、基质金属蛋白酶(MMP)-2和MMP-7的表达(均P<0.01)。体内实验显示,敲降METTL5减缓了移植瘤生长和Wnt/β-catenin信号活性。结论敲降METTL5能抑制TNBC细胞的增殖、迁移与侵袭,其作用可能与抑制Wnt/β-catenin信号通路有关。展开更多
目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结...目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结肠癌组织、正常结肠细胞系(NCM460)和结直肠癌细胞系(SW620、HCT116、HT29、Lovo和SW480)中的表达。将SCL6A9过表达质粒及阴性对照(SLC6A9 OE、Vector)转染HT29细胞,将SCL6A9小干扰RNA及阴性对照(SLC6A9 siRNA1#、siRNA2#和Scramble)转染SW620细胞。划痕愈合实验和Transwell实验检测各组细胞的迁移、侵袭能力。Western blot和细胞免疫荧光检测EMT相关蛋白E-cadherin、Vimentin的表达水平。利用CCK-8法和构建裸鼠移植瘤模型检测SLC6A9过表达对结直肠癌细胞5-FU药物敏感性的影响。结果:与正常结肠组织和NCM460细胞相比,SLC6A9在结肠癌组织和结直肠癌细胞系中低表达(均P<0.05)。SLC6A9过表达引起E-cadherin蛋白表达增加,Vimentin蛋白水平降低,抑制结直肠癌细胞的迁移、侵袭(P<0.05)。SLC6A9低表达引起E-cadherin蛋白表达降低,Vimentin蛋白水平增加,促进结直肠癌细胞的迁移、侵袭能力(P<0.05)。SLC6A9过表达提高了5-FU的药物敏感性,并使肿瘤生长缓慢,质量减轻(P<0.05)。而SLC6A9低表达降低了5-FU的药物敏感性(P<0.05)。结论:SLC6A9过表达能够抑制结直肠癌细胞的迁移、侵袭和EMT进程,并增强5-FU对结直肠癌细胞的药物敏感性。展开更多
食品加工过程中的美拉德反应有助于形成一些热诱导毒性产物,包括晚期糖基化终末产物(advanced glycation end products,AGEs)和5-羟甲基糠醛(5-hydroxymethylfurfural,5-HMF)。食源性AGEs在体内的积累和循环与糖尿病并发症的发生有关,...食品加工过程中的美拉德反应有助于形成一些热诱导毒性产物,包括晚期糖基化终末产物(advanced glycation end products,AGEs)和5-羟甲基糠醛(5-hydroxymethylfurfural,5-HMF)。食源性AGEs在体内的积累和循环与糖尿病并发症的发生有关,同时可能诱发氧化应激、炎症和动脉粥样硬化。5-HMF的代谢物5-磺基氧甲基糠醛(5-sulfooxymethylfurfural,5-SMF)有潜在基因毒性和致癌性。如何控制热加工食品中这些危害物的形成已成为食品行业的关注焦点。本文从美拉德反应和焦糖化反应两条途径探究了AGEs和5-HMF的形成机理,并对近5年二者的检测方法进行了综述,阐述了各类方法的优缺点,以期为建立二者的通用检测方法奠定基础。在此基础上,从削减前体物质的供给、阻断中间体的转化,以及去除已经生成的AGEs和5-HMF这3个方面着手,综述了近年来相应所采用的抑制策略,以期为AGEs和5-HMF在食品中的控制及热加工食品质量与安全管理提供理论依据。展开更多
基金Supported by Science and Technology Planning Project of Zhejiang Province,No.LGF20H160001.
文摘BACKGROUND The relationship between hepatitis B surface antigen(HBsAg)-positive carrier status and liver cancer has been extensively studied.However,the epigenetic changes that occur during progression from HBsAg-positive carrier status or cirrhosis to liver cancer are unknown.The epigenetic modification of DNA hydroxymethylation is critical in tumor development.Further,5-hydroxymethylcytosine(5hmC)is an important base for DNA demethylation and epigenetic regulation.It is also involved in the assembly of chromosomes and the regulation of gene expression.However,the mechanism of action of 5hmC in HBsAgpositive carriers or patients with cirrhosis who develop liver cancer has not been fully elucidated.AIM To investigate the possible epigenetic mechanism of HBsAg-positive carriers and hepatocellular carcinoma(HCC)progression from cirrhosis.METHODS Forty HBsAg-positive carriers,forty patients with liver cirrhosis,and forty patients with liver cancer admitted to the First People's Hospital of Yongkang between March 2020 and November 2021 were selected as participants.Free DNA was extracted using a cf-DNA kit.cfDNA was extracted by 5hmC DNA sequencing for principal component analysis,the expression profiles of the three groups of samples were detected,and the differentially expressed genes(DEGs)modified by hydroxymethylation were screened.Bioinformatic analysis was used to enrich DEGs,such as in biological pathways.RESULTS A total of 16455 hydroxymethylated genes were identified.Sequencing results showed that 32 genes had significant 5hmC modification differences between HBsAg carriers and liver cancer patients,of which 30 were upregulated and 2 downregulated in patients with HCC compared with HBsAg-positive carriers.Significant 5hmC modification differences between liver cirrhosis and liver cancer patients were identified in 20 genes,of which 17 were upregulated and 3 were downregulated in patients with HCC compared with those with cirrhosis.These genes may have potential loci that are undiscovered or unelucidated,which contribute to the development and progression of liver cancer.Analysis of gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes showed that the major signaling pathways involved in the differential genes were biliary secretion and insulin secretion.The analysis of protein interactions showed that the important genes in the protein-protein interaction network were phosphoenolpyruvate carboxykinase and solute carrier family 2.CONCLUSION The occurrence and development of liver cancer involves multiple genes and pathways,which may be potential targets for preventing hepatitis B carriers from developing liver cancer.
基金Supported by National Natural Science Foundation of China,No.81874279Scientific and Technological Development Program of Jilin Province,No.20190201093JC and No.20200201326JC+1 种基金Jilin Province Department of Finance,No.JLSWSRCZX2020-010Youth Development Fund from First Hospital of Jilin University,No.JDYY11202021.
文摘BACKGROUND Most gastric cancer(GC)patients are diagnosed at middle or late stage because the symptoms in early stage are obscure,which causes higher mortality rates of GC.Helicobacter pylori(H.pylori)was identified as a class I carcinogen and leads to aberrant DNA methylation/hydroxymethylation.5-hydroxymethylcytosine(5-hmC)plays complex roles in gene regulation of tumorigenesis and can be considered as an activating epigenetic mark of hydroxymethylation.AIM To explore the association between 5-hmC levels and the progression and prognosis of GC patients with or without H.pylori infection.METHODS A retrospective cohort study was conducted to estimate the predicted value of 5-hmC level in the progression and prognosis of GC patients with different H.pylori infection status.A total of 144 GC patients were recruited.RESULTS The levels of 5-hmC were significantly decreased in tumor tissues(0.076±0.048)compared with the matched control tissues(0.110±0.057,P=0.001).A high level of 5-hmC was an independent significant favorable predictor of overall survival in GC patients(hazard ratio=0.61,95% confidence interval:0.38-0.98,P=0.040),the H.pylori-negative GC subgroup(hazard ratio=0.30,95% confidence interval:0.13-0.68,P=0.004)and the GC patients with TNM stage Ⅰ or Ⅱ(hazard ratio=0.32,95% confidence interval:0.13-0.77,P=0.011).CONCLUSION Increased 5-hmC is a favorable prognostic factor in GC,especially for H.pylori-negative subgroups.
基金This work was partly supported by a grant from the National Institutes of Health P30 C060553 Career Development Fund(to W.Z.)
文摘Robust and clinically convenient biomarkers for cancer diagnosis,early detection,and prognosis have great potential to improve patient survival and are the key to precision medicine.The advent of next-generation sequencing technologies enables a more sensitive and comprehensive profiling of genetic and epigenetic information in tumor-derived materials.Researchers are now able to monitor the dynamics of tumorigenesis in new dimensions,such as using circulating cell-free DNA(cfDNA)and tumor DNA(ctDNA).Mutation-based assays in liquid biopsy cannot always provide consistent results across studies due partly to intra-and inter-tumoral heterogeneity as well as technical limitations.In contrast,epigenetic analysis of patient-derived cfDNA is a promising alternative,especially for early detection and disease surveillance,because epigenetic modifications are tissue-specific and reflect the dynamic process of cancer progression.Therefore,cfDNA-based epigenetic assays are emerging to be a highly sensitive,minimally invasive tool for cancer diagnosis and prognosis with great potential in future precise care of cancer patients.The major obstacle for applying epigenetic analysis of cfDNA,however,has been the lack of enabling techniques with high sensitivity and technical robustness.In this review,we summarized the advances in epigenome-wide profiling of 5-hydroxymethyl-cytosine(5hmC)in cfDNA,focusing on the detection approaches and potential role as biomarkers in different cancer types.
文摘Background: DNA hydroxymethylation refers to a chemical modification process in which 5-methylcytosine (5mC) is catalyzed to 5-hydroxymethylcytosine (5hmC) by ten-eleven translocation (TET) family proteins. Recent studies have revealed that aberrant TETs expression or 5hmC level may play important roles in the occurrence and development of various pathological and physiological processes including cancer and aging. This study aimed to explore the relation between aberrant DNA hydroxymethylation with skin photoaging and to investigate the levels of TETs, 5mC, and 5hmC expression 24 h after 40 mJ/cm^2 and 80 mJ/cm^2 doses of ultraviolet B (UVB) irradiation to HaCaT cells. Methods: To explore whether aberrant DNA hydroxymethylation is also related to skin photoaging, 40 mJ/cm^2 and 80 mJ/cm^2 doses of UVB were chosen to treat keratinocytes (HaCaT cells). After 24 h of UVB irradiation, 5mC and 5hmC levels were determined by immunohistochemistry (IHC) and immunofluorescence (IF), and at the same time, the expression levels of matrix metalloproteinase 1 (MMP-1) and TETs were assessed by reverse transcription-polymerase chain reaction or Western blot analysis. Results: After 40 mJ/cm^2 and 80 mJ/cm^2 doses of UVB exposure, both IHC and IF results showed that 5hmC levels increased significantly, while the 5mC levels did not exhibit significant changes in HaCaT cells, compared with HaCat cells without UVB exposure. Moreover, compared with HaCat cells without UVB exposure, the levels ofTET1, TET2, and TET3 mRNA and protein expression were significantly upregulated (mRNA: P = 0.0022 and 0.0043 for TET1; all P 〈 0.0001 for TET2; all P = 0.0006 for TET3; protein: P = 0.0012 and 0.0006 tbr TET 1 ; all P = 0.0022 for TET2; and all P = 0.0002 for TET3), and the levels of MMP- 1 mRNA expression increased dose dependently in 40 mJ/cm^2 and 80 mJ/cm^2 UVB-irradiated groups. Conclusion: UVB radiation could cause increased 5hmC and TET expression, which might become a novel biomarker in UVB-related skin aging.
基金supported by the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(Grant Nos.2016ZX310182-2 and 2016ZX310176-6 to NY)the Medical Epigenetics Research Center,Chinese Academy of Medical Sciences(Grant Nos.2017PT31035 and 2018PT31035 to NY)the National Natural Science Foundation of China(Grant No.81773163 to JF)
文摘Although DNA 5-hydroxymethylcytosine(5 hmC)is recognized as an important epigenetic mark in cancer,its precise role in lymph node metastasis remains elusive.In this study,we investigated how 5 hmC associates with lymph node metastasis in breast cancer.Accompanying with high expression of TET1 and TET2 proteins,large numbers of genes in the metastasis-positive primary tumors exhibit higher 5 hmC levels than those in the metastasis-negative primary tumors.In contrast,the TET protein expression and DNA 5 hmC decrease significantly within the metastatic lesions in the lymph nodes compared to those in their matched primary tumors.Through genomewide analysis of 8 sets of primary tumors,we identified 100 high-confidence metastasis-associated5 hmC signatures,and it is found that increased levels of DNA 5 hmC and gene expression of MAP7 D1 associate with high risk of lymph node metastasis.Furthermore,we demonstrate that MAP7 D1,regulated by TET1,promotes tumor growth and metastasis.In conclusion,the dynamic5 hmC profiles during lymph node metastasis suggest a link between DNA 5 hmC and lymph node metastasis.Meanwhile,the role of MAP7 D1 in breast cancer progression suggests that the metastasis-associated 5 hmC signatures are potential biomarkers to predict the risk for lymph node metastasis,which may serve as diagnostic and therapeutic targets for metastatic breast cancer.
文摘目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结肠癌组织、正常结肠细胞系(NCM460)和结直肠癌细胞系(SW620、HCT116、HT29、Lovo和SW480)中的表达。将SCL6A9过表达质粒及阴性对照(SLC6A9 OE、Vector)转染HT29细胞,将SCL6A9小干扰RNA及阴性对照(SLC6A9 siRNA1#、siRNA2#和Scramble)转染SW620细胞。划痕愈合实验和Transwell实验检测各组细胞的迁移、侵袭能力。Western blot和细胞免疫荧光检测EMT相关蛋白E-cadherin、Vimentin的表达水平。利用CCK-8法和构建裸鼠移植瘤模型检测SLC6A9过表达对结直肠癌细胞5-FU药物敏感性的影响。结果:与正常结肠组织和NCM460细胞相比,SLC6A9在结肠癌组织和结直肠癌细胞系中低表达(均P<0.05)。SLC6A9过表达引起E-cadherin蛋白表达增加,Vimentin蛋白水平降低,抑制结直肠癌细胞的迁移、侵袭(P<0.05)。SLC6A9低表达引起E-cadherin蛋白表达降低,Vimentin蛋白水平增加,促进结直肠癌细胞的迁移、侵袭能力(P<0.05)。SLC6A9过表达提高了5-FU的药物敏感性,并使肿瘤生长缓慢,质量减轻(P<0.05)。而SLC6A9低表达降低了5-FU的药物敏感性(P<0.05)。结论:SLC6A9过表达能够抑制结直肠癌细胞的迁移、侵袭和EMT进程,并增强5-FU对结直肠癌细胞的药物敏感性。
文摘食品加工过程中的美拉德反应有助于形成一些热诱导毒性产物,包括晚期糖基化终末产物(advanced glycation end products,AGEs)和5-羟甲基糠醛(5-hydroxymethylfurfural,5-HMF)。食源性AGEs在体内的积累和循环与糖尿病并发症的发生有关,同时可能诱发氧化应激、炎症和动脉粥样硬化。5-HMF的代谢物5-磺基氧甲基糠醛(5-sulfooxymethylfurfural,5-SMF)有潜在基因毒性和致癌性。如何控制热加工食品中这些危害物的形成已成为食品行业的关注焦点。本文从美拉德反应和焦糖化反应两条途径探究了AGEs和5-HMF的形成机理,并对近5年二者的检测方法进行了综述,阐述了各类方法的优缺点,以期为建立二者的通用检测方法奠定基础。在此基础上,从削减前体物质的供给、阻断中间体的转化,以及去除已经生成的AGEs和5-HMF这3个方面着手,综述了近年来相应所采用的抑制策略,以期为AGEs和5-HMF在食品中的控制及热加工食品质量与安全管理提供理论依据。