Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy ...Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy targets are not well understood.Methods:We conducted a systematic analysis using TCGA Pan-Cancer Atlas data and Gene Set Cancer Analysis results to examine the expression profiles of 15 DNA polymerases(POLYs)and their clinical correlations.We also evaluated the prognostic value of POLYs by analyzing their expression levels in relation to overall survival time(OS)using Kaplan-Meier survival curves.Additionally,we investigated the correlations between POLY expression and immune cells,DNA damage repair(DDR)pathways,and ubiquitination.Drug sensitivity analysis was performed to assess the relationship between POLY expression and drug response.Results:Our analysis revealed that 14 out of 15 POLYs exhibited significantly distinct expression patterns between tumor and normal samples across most cancer types,except for DNA nucleotidylexotransferase(DNTT).Specifically,POLD1 and POLE showed elevated expression in almost all cancers,while POLQ exhibited high expression levels in all cancer types.Some POLYs showed heightened expression in specific cancer subtypes,while others exhibited low expression.Kaplan-Meier survival curves demonstrated significant prognostic value of POLYs in multiple cancers,including PAAD,KIRC,and ACC.Cox analysis further validated these findings.Alteration patterns of POLYs varied significantly among different cancer types and were associated with poorer survival outcomes.Significant correlations were observed between the expression of POLY members and immune cells,DDR pathways,and ubiquitination.Drug sensitivity analysis indicated an inverse relationship between POLY expression and drug response.Conclusion:Our comprehensive study highlights the significant role of POLYs in cancer development and identifies them as promising prognostic and immunological biomarkers for various cancer types.Additionally,targeting POLYs therapeutically holds promise for tumor immunotherapy.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
Background: While sunscreen has been accepted as a mainline defence against photodamage from ultraviolet, visible light and near-infrared radiation, there appears to be a lack of research into photorepair. The concept...Background: While sunscreen has been accepted as a mainline defence against photodamage from ultraviolet, visible light and near-infrared radiation, there appears to be a lack of research into photorepair. The concept of protecting the skin during the day and repairing cellular damage at night is intuitive, yet specific strategies revolving around combinations of proven reparative active ingredients remain unelucidated. Purpose: To investigate the efficacy of a solar repair Formulation following ultraviolet and environmental exposure in order to improve overall skin health and appearance through three hypotheses: The Formulation increases expression of DNA repair mechanisms markers;The Formulation enhances overall skin appearance through reducing signs of inflammation, elevating hydration, reinforcing skin firmness and amplifying radiance;In-Vivo efficacy test results are aligned with measured gene expression changes. Methods: The Formulation (#6NIC1.V1.1-1) was tested for: In-vitro LDH cytotoxicity activity, In-vitro qPCR gene expression with and without ultraviolet exposure on a reconstructed 3-dimensional skin model, and In-Vivo efficacy study on a panel of 22 participants objectively and subjectively. Results: Skin radiance, firmness, hydration, redness, and inflammation are significantly improved after In-Vivo skin exposure to the Formulation and environmental challenges such as ultraviolet radiation. These outcomes were confirmed by in-vitro genetic testing on a reconstructed human skin model. Conclusion: The studies allowed us to identify and group results in four main skin functions that were significantly enhanced following the application of the Formulation: firmness, hydration, radiance and soothing.展开更多
For first-line non-small-cell lung cancer(NSCLC) therapy,detecting mutation status of the epidermal growth factor receptor(EGFR) gene constitutes a prudent test to identify patients who are most likely to benefit ...For first-line non-small-cell lung cancer(NSCLC) therapy,detecting mutation status of the epidermal growth factor receptor(EGFR) gene constitutes a prudent test to identify patients who are most likely to benefit from EGFR-tyrosine kinase inhibitor(TKI) therapy.Now,the material for detecting EGFR gene mutation status mainly comes from formalin-fixed and paraffin-embedded(FFPE) tissues.DNA extraction from FFPE and the amplification of EGFR gene by polymerase chain reaction(PCR) are two key steps for detecting EGFR gene mutation.We showed a simple method of DNA extraction from FFPE tissues for the effective amplification of EGFR gene.Extracting DNA from the FFPE tissues of NSCLC patients with 1% Triton X-100(pH=10.0) was performed by heating at 95 °C for 30 min.Meanwhile,a commercial kit was used to extract DNA from the same FFPE tissues of NSCLC patients for comparison.DNA extracted products were used as template for amplifying the exons 18,19,20 and 21 of EGFR by PCR for different amplified fragments.Results show that DNA fragment size extracted from FFPE tissues with 1% Triton X was about 250―500 base pairs(bp).However,DNA fragment size extracted from FFPE tissues via commercial kit was about from several hundreds to several thousands bp.The DNA yield extracted from FFPE tissues with 1% Triton X was larger than that via commercial kit.For about 500 bp fragment,four exons of EGFR could not be amplified more efficiently from extracted DNA with 1% Triton X than with commercial kit.However,for about 200 bp fragment.This simple and non-laborious protocol could successfully be used to extract DNA from FFPE tissue for the amplification of EGFR gene by PCR,further screening of EGFR gene mutation and facilitating the molecular analysis of a large number of FFPE tissues from NSCLC patients.展开更多
AIM: To look for a rapid low-cost technique for the detection of HBV variants.METHODS: Two patients who underwent orthotopic liver transplantation (OLT) for HBV infection were treated with lamivudine (100 mg daily) an...AIM: To look for a rapid low-cost technique for the detection of HBV variants.METHODS: Two patients who underwent orthotopic liver transplantation (OLT) for HBV infection were treated with lamivudine (100 mg daily) and HBV infection recurred in the grafted livers. The patients were monitored intensively for liver enzymes, hepatitis B surface antigen (HBsAg) and HBV DNA in serum. Liver biopsy was performed regularly. HBV DNA in a conserved polymerase domain (the YMDD locus) was amplified from serum of each patient by PCR and sequenced. HBV genotypes were analyzed by restriction fragment length polymorphism (RFLP) of the PCR products generated from a fragment of the polymerase gene.RESULTS: YMDD wild-type HBV was detected in one patient by PCR-RFLP and DNA sequencing 19 mo after OLT, and YIDD mutant-type HBV in the other patient, 16 mo after OLT.CONCLUSION: PCR-RFLP assay is an accurate and simple method for genotyping lamivudine-resistant HBV variants.展开更多
A simple method for constructing polymerized genes using only restriction enzymes and commercially available cloning systems was established. In this system, gel isolations or purifications of target genes after restr...A simple method for constructing polymerized genes using only restriction enzymes and commercially available cloning systems was established. In this system, gel isolations or purifications of target genes after restriction enzyme digestions or PCR amplifications, which often cause errors and mutations in the target gene sequence, are not necessary. To verify the usefulness of this method, one, two, four, eight, and sixteen tandem-repeats of the Green Fluorescent Protein (GFP) expression gene in Escherichia coli were sequentially constructed. Efficacies of the GFP gene expression of those plasmids in E. coli showed an increasing trend in accordance with the copy numbers of the gene. On SDS polyacrylamide gel electrophoresis with Coomassie blue staining, no expressed protein could be seen in E. coli cells harboring plasmids that contained one or two copies of the gene. However, expressed protein bands in E. coli cells were clearly detected with 4 copies of the gene. In quantitative analyses involving green fluorescence intensities per culture volume, the expression level in E. coli with 16 copies of the gene was 36.3-fold higher than that in E. coli with one copy at 22 hours after induction.展开更多
Objective To explore the toxicological mechanism of hydroquinone in human bronchial epithelial cells and to investigate whether DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone. M...Objective To explore the toxicological mechanism of hydroquinone in human bronchial epithelial cells and to investigate whether DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone. Methods DNA polymerase beta knock-down cell line was established via RNA interference as an experimental group. Normal human bronchial epithelial cells and cells transfected with the empty vector of pEGFP-C1 were used as controls. Cells were treated with different concentrations of hydroquinone (ranged from 10 μmol/L to 120 μmol/L) for 4 hours. MTT assay and Comet assay [single-cell gel electrophoresis (SCGE)] were performed respectively to detect the toxicity of hydroquinone. Results assay showed that DNA polymerase beta knock-down cells treated with different concentrations of hydroquinone had a lower absorbance value at 490 nm than the control cells in a dose-dependant manner. Comet assay revealed that different concentrations of hydroquinone caused more severe DNA damage in DNA polymerase beta knock-down cell line than in control cells and there was no significant difference in the two control groups. Conclusions Hydroquinone has significant toxicity to human bronchial epithelial cells and causes DNA damage. DNA polymerase beta knock-down cell line appears more sensitive to hydroquinone than the control cells. The results suggest that DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone.展开更多
AIM: To observe the variation of DNA polymerase β (polβ)in esophageal carcinoma.METHODS: Thirty specimens containing adjacent normal epithelial tissues were collected from patients in Linzhou region (a high risk are...AIM: To observe the variation of DNA polymerase β (polβ)in esophageal carcinoma.METHODS: Thirty specimens containing adjacent normal epithelial tissues were collected from patients in Linzhou region (a high risk area for esophageal squamous carcinoma) and 25 specimens were from a non-high risk area. Total RNA was extracted from the samples and reverse transcription polymerase chain reaction (RT-PCR) was performed. PCR products were cloned and sequenced to investigate the polβ gene with DNASIS and OMIGA. Statistical significance was evaluated using the x2 test.RESULTS: High-incidence area group: polβ gene variation was detected in 13 of 30 esophageal carcinoma tissue specimens, and only one variation was found in 30corresponding adjacent normal tissue specimens. Non high-incidence area group: polβ gene variation was detected in 5 of 25 esophageal carcinoma tissue specimens,and no variation was found in 25 corresponding adjacent normal tissue specimens. The incidence of polβ gene variation observed in the high-incidence area group was significantly higher than in the non-high incidence area group. Two mutation hot spots (454-466 and 648-670 nt)and a 58 bp deletion (177-234 nt) were found.CONCLUSION: Variations of polβ perform different functions between the high-incidence areas and the other areas, and may play a more important role in the high-incidence areas.展开更多
在他们描述脱氧核糖核酸双螺旋,沃森和克里克的结构写了什么可以是在科学文学的最大的保守的陈述之一的精液的出版,也就是那“这没疏忽特定的配对我们立即要求了为遗传物质建议可能的拷贝机制。“半个世纪以后,我们更充分欣赏它是与...在他们描述脱氧核糖核酸双螺旋,沃森和克里克的结构写了什么可以是在科学文学的最大的保守的陈述之一的精液的出版,也就是那“这没疏忽特定的配对我们立即要求了为遗传物质建议可能的拷贝机制。“半个世纪以后,我们更充分欣赏它是与精确性复制 60 亿核苷酸的巨大的挑战需要稳定地在许多代上维持人的染色体的。这挑战也许比大 50 年以前被认识到,因为随后的研究表明了染色体能被在脱氧核糖核酸而且由现在质问到复制的正常脱氧核糖核酸的各种各样的顺序主题产生潜在地细胞毒素、诱变的损害的一个大数字和变化的环境压力使动摇不仅。向染色体稳定性的许多决定因素的更好的理解,这章考察 undamaged 和损坏脱氧核糖核酸与被拷贝的忠实,与真核细胞的 B 家庭和 Y 家庭 DNA 的一个焦点,并且考虑这忠实怎么被完成。展开更多
基金supported by the project of funds by the Consultation of Provincial Department and University for S&T Innovation granted by Hebei Provincial Department of Science and Technology and Hebei Medical University(2020TXZH04).
文摘Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy targets are not well understood.Methods:We conducted a systematic analysis using TCGA Pan-Cancer Atlas data and Gene Set Cancer Analysis results to examine the expression profiles of 15 DNA polymerases(POLYs)and their clinical correlations.We also evaluated the prognostic value of POLYs by analyzing their expression levels in relation to overall survival time(OS)using Kaplan-Meier survival curves.Additionally,we investigated the correlations between POLY expression and immune cells,DNA damage repair(DDR)pathways,and ubiquitination.Drug sensitivity analysis was performed to assess the relationship between POLY expression and drug response.Results:Our analysis revealed that 14 out of 15 POLYs exhibited significantly distinct expression patterns between tumor and normal samples across most cancer types,except for DNA nucleotidylexotransferase(DNTT).Specifically,POLD1 and POLE showed elevated expression in almost all cancers,while POLQ exhibited high expression levels in all cancer types.Some POLYs showed heightened expression in specific cancer subtypes,while others exhibited low expression.Kaplan-Meier survival curves demonstrated significant prognostic value of POLYs in multiple cancers,including PAAD,KIRC,and ACC.Cox analysis further validated these findings.Alteration patterns of POLYs varied significantly among different cancer types and were associated with poorer survival outcomes.Significant correlations were observed between the expression of POLY members and immune cells,DDR pathways,and ubiquitination.Drug sensitivity analysis indicated an inverse relationship between POLY expression and drug response.Conclusion:Our comprehensive study highlights the significant role of POLYs in cancer development and identifies them as promising prognostic and immunological biomarkers for various cancer types.Additionally,targeting POLYs therapeutically holds promise for tumor immunotherapy.
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.
文摘Background: While sunscreen has been accepted as a mainline defence against photodamage from ultraviolet, visible light and near-infrared radiation, there appears to be a lack of research into photorepair. The concept of protecting the skin during the day and repairing cellular damage at night is intuitive, yet specific strategies revolving around combinations of proven reparative active ingredients remain unelucidated. Purpose: To investigate the efficacy of a solar repair Formulation following ultraviolet and environmental exposure in order to improve overall skin health and appearance through three hypotheses: The Formulation increases expression of DNA repair mechanisms markers;The Formulation enhances overall skin appearance through reducing signs of inflammation, elevating hydration, reinforcing skin firmness and amplifying radiance;In-Vivo efficacy test results are aligned with measured gene expression changes. Methods: The Formulation (#6NIC1.V1.1-1) was tested for: In-vitro LDH cytotoxicity activity, In-vitro qPCR gene expression with and without ultraviolet exposure on a reconstructed 3-dimensional skin model, and In-Vivo efficacy study on a panel of 22 participants objectively and subjectively. Results: Skin radiance, firmness, hydration, redness, and inflammation are significantly improved after In-Vivo skin exposure to the Formulation and environmental challenges such as ultraviolet radiation. These outcomes were confirmed by in-vitro genetic testing on a reconstructed human skin model. Conclusion: The studies allowed us to identify and group results in four main skin functions that were significantly enhanced following the application of the Formulation: firmness, hydration, radiance and soothing.
基金Supported by the Jilin Science & Technology Development Plan,China(No.201201060)the Scientific Research Foundation of Jilin Province,China(No.20100942)+1 种基金the Fund of Developing and Reforming Community of Jilin Province,China(No.2010-1928)the Health Scientific Research Foundation of Jilin Province,China(Nos.2009z081,2010Z083)
文摘For first-line non-small-cell lung cancer(NSCLC) therapy,detecting mutation status of the epidermal growth factor receptor(EGFR) gene constitutes a prudent test to identify patients who are most likely to benefit from EGFR-tyrosine kinase inhibitor(TKI) therapy.Now,the material for detecting EGFR gene mutation status mainly comes from formalin-fixed and paraffin-embedded(FFPE) tissues.DNA extraction from FFPE and the amplification of EGFR gene by polymerase chain reaction(PCR) are two key steps for detecting EGFR gene mutation.We showed a simple method of DNA extraction from FFPE tissues for the effective amplification of EGFR gene.Extracting DNA from the FFPE tissues of NSCLC patients with 1% Triton X-100(pH=10.0) was performed by heating at 95 °C for 30 min.Meanwhile,a commercial kit was used to extract DNA from the same FFPE tissues of NSCLC patients for comparison.DNA extracted products were used as template for amplifying the exons 18,19,20 and 21 of EGFR by PCR for different amplified fragments.Results show that DNA fragment size extracted from FFPE tissues with 1% Triton X was about 250―500 base pairs(bp).However,DNA fragment size extracted from FFPE tissues via commercial kit was about from several hundreds to several thousands bp.The DNA yield extracted from FFPE tissues with 1% Triton X was larger than that via commercial kit.For about 500 bp fragment,four exons of EGFR could not be amplified more efficiently from extracted DNA with 1% Triton X than with commercial kit.However,for about 200 bp fragment.This simple and non-laborious protocol could successfully be used to extract DNA from FFPE tissue for the amplification of EGFR gene by PCR,further screening of EGFR gene mutation and facilitating the molecular analysis of a large number of FFPE tissues from NSCLC patients.
基金Supported by the National Natural Science Foundation of China, No. 30170363 the Major Science and Technology Program of Ministry of Education, No. 01003 the Major State Basic Research Development Program of China, No. 2002CB513100 the National Key Technology Research and Development Program of China during the 10~(th) Five-Year Plan Period, No. 2001BA703B05
文摘AIM: To look for a rapid low-cost technique for the detection of HBV variants.METHODS: Two patients who underwent orthotopic liver transplantation (OLT) for HBV infection were treated with lamivudine (100 mg daily) and HBV infection recurred in the grafted livers. The patients were monitored intensively for liver enzymes, hepatitis B surface antigen (HBsAg) and HBV DNA in serum. Liver biopsy was performed regularly. HBV DNA in a conserved polymerase domain (the YMDD locus) was amplified from serum of each patient by PCR and sequenced. HBV genotypes were analyzed by restriction fragment length polymorphism (RFLP) of the PCR products generated from a fragment of the polymerase gene.RESULTS: YMDD wild-type HBV was detected in one patient by PCR-RFLP and DNA sequencing 19 mo after OLT, and YIDD mutant-type HBV in the other patient, 16 mo after OLT.CONCLUSION: PCR-RFLP assay is an accurate and simple method for genotyping lamivudine-resistant HBV variants.
文摘A simple method for constructing polymerized genes using only restriction enzymes and commercially available cloning systems was established. In this system, gel isolations or purifications of target genes after restriction enzyme digestions or PCR amplifications, which often cause errors and mutations in the target gene sequence, are not necessary. To verify the usefulness of this method, one, two, four, eight, and sixteen tandem-repeats of the Green Fluorescent Protein (GFP) expression gene in Escherichia coli were sequentially constructed. Efficacies of the GFP gene expression of those plasmids in E. coli showed an increasing trend in accordance with the copy numbers of the gene. On SDS polyacrylamide gel electrophoresis with Coomassie blue staining, no expressed protein could be seen in E. coli cells harboring plasmids that contained one or two copies of the gene. However, expressed protein bands in E. coli cells were clearly detected with 4 copies of the gene. In quantitative analyses involving green fluorescence intensities per culture volume, the expression level in E. coli with 16 copies of the gene was 36.3-fold higher than that in E. coli with one copy at 22 hours after induction.
基金This work was supported by a grant from the Major State Basic Research Development Program of China (No. 2002CB512904, 2002CB512903).
文摘Objective To explore the toxicological mechanism of hydroquinone in human bronchial epithelial cells and to investigate whether DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone. Methods DNA polymerase beta knock-down cell line was established via RNA interference as an experimental group. Normal human bronchial epithelial cells and cells transfected with the empty vector of pEGFP-C1 were used as controls. Cells were treated with different concentrations of hydroquinone (ranged from 10 μmol/L to 120 μmol/L) for 4 hours. MTT assay and Comet assay [single-cell gel electrophoresis (SCGE)] were performed respectively to detect the toxicity of hydroquinone. Results assay showed that DNA polymerase beta knock-down cells treated with different concentrations of hydroquinone had a lower absorbance value at 490 nm than the control cells in a dose-dependant manner. Comet assay revealed that different concentrations of hydroquinone caused more severe DNA damage in DNA polymerase beta knock-down cell line than in control cells and there was no significant difference in the two control groups. Conclusions Hydroquinone has significant toxicity to human bronchial epithelial cells and causes DNA damage. DNA polymerase beta knock-down cell line appears more sensitive to hydroquinone than the control cells. The results suggest that DNA polymerase beta is involved in protecting cells from damage caused by hydroquinone.
基金Supported by the National Natural Science Foundation of China,No. 39870287
文摘AIM: To observe the variation of DNA polymerase β (polβ)in esophageal carcinoma.METHODS: Thirty specimens containing adjacent normal epithelial tissues were collected from patients in Linzhou region (a high risk area for esophageal squamous carcinoma) and 25 specimens were from a non-high risk area. Total RNA was extracted from the samples and reverse transcription polymerase chain reaction (RT-PCR) was performed. PCR products were cloned and sequenced to investigate the polβ gene with DNASIS and OMIGA. Statistical significance was evaluated using the x2 test.RESULTS: High-incidence area group: polβ gene variation was detected in 13 of 30 esophageal carcinoma tissue specimens, and only one variation was found in 30corresponding adjacent normal tissue specimens. Non high-incidence area group: polβ gene variation was detected in 5 of 25 esophageal carcinoma tissue specimens,and no variation was found in 25 corresponding adjacent normal tissue specimens. The incidence of polβ gene variation observed in the high-incidence area group was significantly higher than in the non-high incidence area group. Two mutation hot spots (454-466 and 648-670 nt)and a 58 bp deletion (177-234 nt) were found.CONCLUSION: Variations of polβ perform different functions between the high-incidence areas and the other areas, and may play a more important role in the high-incidence areas.
文摘在他们描述脱氧核糖核酸双螺旋,沃森和克里克的结构写了什么可以是在科学文学的最大的保守的陈述之一的精液的出版,也就是那“这没疏忽特定的配对我们立即要求了为遗传物质建议可能的拷贝机制。“半个世纪以后,我们更充分欣赏它是与精确性复制 60 亿核苷酸的巨大的挑战需要稳定地在许多代上维持人的染色体的。这挑战也许比大 50 年以前被认识到,因为随后的研究表明了染色体能被在脱氧核糖核酸而且由现在质问到复制的正常脱氧核糖核酸的各种各样的顺序主题产生潜在地细胞毒素、诱变的损害的一个大数字和变化的环境压力使动摇不仅。向染色体稳定性的许多决定因素的更好的理解,这章考察 undamaged 和损坏脱氧核糖核酸与被拷贝的忠实,与真核细胞的 B 家庭和 Y 家庭 DNA 的一个焦点,并且考虑这忠实怎么被完成。