AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of C...AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of China, these factors are not so important in the etiology of HCC. Therefore, the point mutation of p53 exon7 may also be different than that in HCC-prevalent areas of China. The aim of this study is to investigate the status and carcinogenic role of the point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province, a non-HCC-prevalent area in China. METHODS: PCR PCR-SSCP and PCR-RFLP were applied to analyze the homozygous deletion and point mutation of p53 exon7 in HCC samples from Anhui, which were confirmed by DNA sequencing and Genbank comparison. RESULTS: In the 38 samples of hepatocellular carcinoma, no homozygous deletion of p53 exon7 was detected and point mutations of p53 exon7 were found in 4 cases, which were found to be heterozygous mutation of codon 249 with a mutation rate of 10.53%(4/38). The third base mutation(G-T) of p53 codon 249 was found by DNA sequencing and Genbank comparison. CONCLUSION: The incidence of point mutation of p53 codon 249 is lower in hepatocellular carcinoma and the heterozygous mutation of p53 exon7 found in these patients only indicate that they have genetic susceptibility to HCC. p53 codon 249 is a hotspot of p53 exon7 point mutation, suggesting that the point mutation of p53 exon 7 may not play a major role in the carcinogenesis of HCC in Anhui Province, a non-HCC-prevalent area in China.展开更多
目的:分析BRAF^(V600E)和RAS基因突变在甲状腺乳头状癌(PTC)中的发生情况,研究BRAF^(V600E)和RAS基因突变与PTC各临床病理特征及预后的相关性。方法:通过cBioPortal网站下载整理癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中PT...目的:分析BRAF^(V600E)和RAS基因突变在甲状腺乳头状癌(PTC)中的发生情况,研究BRAF^(V600E)和RAS基因突变与PTC各临床病理特征及预后的相关性。方法:通过cBioPortal网站下载整理癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中PTC的相关信息,选取资料完善的402例PTC样本的基因突变和临床信息进行分析。先单因素分析BRAF^(V600E)和RAS基因突变与临床病理参数的相关性,再对其进行多因素Logistic回归分析。结果:在402例PTC中,BRAF^(V600E)的突变率为48.5%(195/402),RAS基因突变率为10.2%(41/402)。单因素分析显示BRAF^(V600E)突变与患者的年龄、性别无关(P>0.05),与有无淋巴结转移、有无腺外侵犯、分期、复发进展和病理亚型有关(P<0.05);RAS基因突变与患者年龄、性别、分期、复发进展无关(P>0.05),与有无淋巴结转移、有无腺外侵犯和病理亚型有关(P <0.05)。Logistics回归分析显示BRAF^(V600E)基因突变与有无腺外侵犯和PTC的病理亚型有关(P<0.05),RAS基因突变与有无淋巴结转移、有无腺外侵犯和PTC病理亚型有关(P<0.05)。结论:在PTC中,BRAF^(V600E)基因突变率显著高于RAS基因突变率;BRAF^(V600E)和RAS基因突变可作为PTC患者预后的预测因素。展开更多
AIM: To identify the new alternative splicing variants of human CYP2D6 in human extratumoral liver tissue with RT-PCR and sequencing. METHODS: Full length of human CYP2D6 cDNAs was amplificated by reverse transcriptio...AIM: To identify the new alternative splicing variants of human CYP2D6 in human extratumoral liver tissue with RT-PCR and sequencing. METHODS: Full length of human CYP2D6 cDNAs was amplificated by reverse transcription-polymerase chain reaction (RT-PCR) from a human extratumoral liver tissue and cloned into pGEM-T vector. The cDNA was sequenced. Exons from 1 to 4 of human CYP2D6 cDNAs were also amplificated by RT-PCR from extratumoral liver tissues of 17 human hepatocellular carcinomas. Some RT-PCR products were sequenced. Exons 1 to 4 of CYP2D6 gene were amplified by PCR from extratumoral liver tissue DNA. Two PCR products from extratumoral liver tissues expressing skipped mRNA were partially sequenced. RESULTS: One of the CYP2D6 cDNAs had 470 nucleotides from 79 to 548 (3' portion of exons 1 to 5' portion of exon 4), and was skipped. Exons 1 to 4 of CYP2D6 cDNA were assayed with RT-PCR in 17 extratumoral liver tissues. Both wild type and skipped mRNAs were expressed in 4 samples, only wild type mRNA was expressed in 5 samples, and only skipped mRNA was expressed in 8 samples. Two more variants were identified by sequencing the RT-PCR products of exons 1 to 4 of CYP2D6 cDNA. The second variant skipped 411 nucleotides from 175 to 585. This variant was identified in 4 different liver tissues by sequencing the RT-PCR products. We sequenced partially 2 of the PCR products amplified of CYP2D6 exon 1 to exon 4 from extratumoral liver tissue genomic DNA that only expressed skipped mRNA by RT-PCR. No point mutations around exon 1, intron 1, and exon 4, and no deletion in CYP2D6 gene were detected. The third variant was the skipped exon 3, and 153 bp was lost. CONCLUSION: Three new alternative splicing variants of CYP2D6 mRNA have been identified. They may not be caused by gene mutation and may lose CYP2D6 activity and act as a down-regulator of CYP2D6.展开更多
基金the Natural Science Foundation of Anhui Province,No.99044312(WY) and No.9741006(LX)Natural Science Foundation of Anhui Educational Commission,No.JL-97-077(WY).
文摘AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of China, these factors are not so important in the etiology of HCC. Therefore, the point mutation of p53 exon7 may also be different than that in HCC-prevalent areas of China. The aim of this study is to investigate the status and carcinogenic role of the point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province, a non-HCC-prevalent area in China. METHODS: PCR PCR-SSCP and PCR-RFLP were applied to analyze the homozygous deletion and point mutation of p53 exon7 in HCC samples from Anhui, which were confirmed by DNA sequencing and Genbank comparison. RESULTS: In the 38 samples of hepatocellular carcinoma, no homozygous deletion of p53 exon7 was detected and point mutations of p53 exon7 were found in 4 cases, which were found to be heterozygous mutation of codon 249 with a mutation rate of 10.53%(4/38). The third base mutation(G-T) of p53 codon 249 was found by DNA sequencing and Genbank comparison. CONCLUSION: The incidence of point mutation of p53 codon 249 is lower in hepatocellular carcinoma and the heterozygous mutation of p53 exon7 found in these patients only indicate that they have genetic susceptibility to HCC. p53 codon 249 is a hotspot of p53 exon7 point mutation, suggesting that the point mutation of p53 exon 7 may not play a major role in the carcinogenesis of HCC in Anhui Province, a non-HCC-prevalent area in China.
文摘目的:分析BRAF^(V600E)和RAS基因突变在甲状腺乳头状癌(PTC)中的发生情况,研究BRAF^(V600E)和RAS基因突变与PTC各临床病理特征及预后的相关性。方法:通过cBioPortal网站下载整理癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中PTC的相关信息,选取资料完善的402例PTC样本的基因突变和临床信息进行分析。先单因素分析BRAF^(V600E)和RAS基因突变与临床病理参数的相关性,再对其进行多因素Logistic回归分析。结果:在402例PTC中,BRAF^(V600E)的突变率为48.5%(195/402),RAS基因突变率为10.2%(41/402)。单因素分析显示BRAF^(V600E)突变与患者的年龄、性别无关(P>0.05),与有无淋巴结转移、有无腺外侵犯、分期、复发进展和病理亚型有关(P<0.05);RAS基因突变与患者年龄、性别、分期、复发进展无关(P>0.05),与有无淋巴结转移、有无腺外侵犯和病理亚型有关(P <0.05)。Logistics回归分析显示BRAF^(V600E)基因突变与有无腺外侵犯和PTC的病理亚型有关(P<0.05),RAS基因突变与有无淋巴结转移、有无腺外侵犯和PTC病理亚型有关(P<0.05)。结论:在PTC中,BRAF^(V600E)基因突变率显著高于RAS基因突变率;BRAF^(V600E)和RAS基因突变可作为PTC患者预后的预测因素。
基金Supported by the National Key Basic Research and Development Program of China,No.2002CB512901National Natural Science Foundation of China,No.39770868 and Natural Science Foundation of Zhejiang Province,No.397490
文摘AIM: To identify the new alternative splicing variants of human CYP2D6 in human extratumoral liver tissue with RT-PCR and sequencing. METHODS: Full length of human CYP2D6 cDNAs was amplificated by reverse transcription-polymerase chain reaction (RT-PCR) from a human extratumoral liver tissue and cloned into pGEM-T vector. The cDNA was sequenced. Exons from 1 to 4 of human CYP2D6 cDNAs were also amplificated by RT-PCR from extratumoral liver tissues of 17 human hepatocellular carcinomas. Some RT-PCR products were sequenced. Exons 1 to 4 of CYP2D6 gene were amplified by PCR from extratumoral liver tissue DNA. Two PCR products from extratumoral liver tissues expressing skipped mRNA were partially sequenced. RESULTS: One of the CYP2D6 cDNAs had 470 nucleotides from 79 to 548 (3' portion of exons 1 to 5' portion of exon 4), and was skipped. Exons 1 to 4 of CYP2D6 cDNA were assayed with RT-PCR in 17 extratumoral liver tissues. Both wild type and skipped mRNAs were expressed in 4 samples, only wild type mRNA was expressed in 5 samples, and only skipped mRNA was expressed in 8 samples. Two more variants were identified by sequencing the RT-PCR products of exons 1 to 4 of CYP2D6 cDNA. The second variant skipped 411 nucleotides from 175 to 585. This variant was identified in 4 different liver tissues by sequencing the RT-PCR products. We sequenced partially 2 of the PCR products amplified of CYP2D6 exon 1 to exon 4 from extratumoral liver tissue genomic DNA that only expressed skipped mRNA by RT-PCR. No point mutations around exon 1, intron 1, and exon 4, and no deletion in CYP2D6 gene were detected. The third variant was the skipped exon 3, and 153 bp was lost. CONCLUSION: Three new alternative splicing variants of CYP2D6 mRNA have been identified. They may not be caused by gene mutation and may lose CYP2D6 activity and act as a down-regulator of CYP2D6.
