As one of the most powerful tools in biomedical research,DNA sequencing not only has been improving its productivity at an exponential growth rate but has also been evolving into a new layout of technological territor...As one of the most powerful tools in biomedical research,DNA sequencing not only has been improving its productivity at an exponential growth rate but has also been evolving into a new layout of technological territories toward engineering and physical disciplines over the past three decades.In this technical review,we look into technical characteristics of the next-generation sequencers and provide insights into their future development and applications.We envisage that some of the emerging platforms are capable of supporting the USD1000 genome and USD100 genome goals if given a few years for technical maturation.We also suggest that scientists from China should play an active role in this campaign that will have a profound impact on both scientific research and societal healthcare systems.展开更多
AIM: To discuss the possible effect of PTEN gene mutations on occurrence and development of gastric cancer. METHODS: Fifty-three gastric cancer specimens were selected to probe PTEN gene mutations in genome of gastric...AIM: To discuss the possible effect of PTEN gene mutations on occurrence and development of gastric cancer. METHODS: Fifty-three gastric cancer specimens were selected to probe PTEN gene mutations in genome of gastric cancer and paracancerous tissues using PCR-SSCP-DNA sequencing method based on microdissection and to observe the protein expression by immunohistochemistry technique. RESULTS: PCR-SSCP-DNA sequencing indicated that 4 kinds of mutation sites were found in 5 of 53 gastric cancer specimens. One kind of mutation was found in exons. AA-TCC mutation was located at 40bp upstream of 3’ lateral exon 7 (115946 AA-TCC). Such mutations led to terminator formation in the 297th codon of the PTEN gene. The other 3 kinds of mutation were found in introns,including a G-C point mutation at 91 bp upstream of 5’ lateral exon 5(90896 G-C),a T-G point mutation at 24 bp upstream of 5’ lateral exon 5 (90963 T-G),and a single base A mutation at 7 bp upstream of 5’ lateral exon 5 (90980 A del). The PTEN protein expression in gastric cancer and paracancerous tissues detected using immunohistochemistry technique indicated that the total positive rate of PTEN protein expression was 66% in gastric cancer tissue,which was significantly lower than that (100%) in paracancerous tissues (P < 0.005). CONCLUSION: PTEN gene mutation and expression may play an important role in the occurrence and development of gastric cancer.展开更多
基金supported by the Chinese Academy of Sciences Scientific Research Equipment (Grant No YZ200823)
文摘As one of the most powerful tools in biomedical research,DNA sequencing not only has been improving its productivity at an exponential growth rate but has also been evolving into a new layout of technological territories toward engineering and physical disciplines over the past three decades.In this technical review,we look into technical characteristics of the next-generation sequencers and provide insights into their future development and applications.We envisage that some of the emerging platforms are capable of supporting the USD1000 genome and USD100 genome goals if given a few years for technical maturation.We also suggest that scientists from China should play an active role in this campaign that will have a profound impact on both scientific research and societal healthcare systems.
基金Zabei Medical Science and Technology Foundation of Shanghai,No.grant 200701
文摘AIM: To discuss the possible effect of PTEN gene mutations on occurrence and development of gastric cancer. METHODS: Fifty-three gastric cancer specimens were selected to probe PTEN gene mutations in genome of gastric cancer and paracancerous tissues using PCR-SSCP-DNA sequencing method based on microdissection and to observe the protein expression by immunohistochemistry technique. RESULTS: PCR-SSCP-DNA sequencing indicated that 4 kinds of mutation sites were found in 5 of 53 gastric cancer specimens. One kind of mutation was found in exons. AA-TCC mutation was located at 40bp upstream of 3’ lateral exon 7 (115946 AA-TCC). Such mutations led to terminator formation in the 297th codon of the PTEN gene. The other 3 kinds of mutation were found in introns,including a G-C point mutation at 91 bp upstream of 5’ lateral exon 5(90896 G-C),a T-G point mutation at 24 bp upstream of 5’ lateral exon 5 (90963 T-G),and a single base A mutation at 7 bp upstream of 5’ lateral exon 5 (90980 A del). The PTEN protein expression in gastric cancer and paracancerous tissues detected using immunohistochemistry technique indicated that the total positive rate of PTEN protein expression was 66% in gastric cancer tissue,which was significantly lower than that (100%) in paracancerous tissues (P < 0.005). CONCLUSION: PTEN gene mutation and expression may play an important role in the occurrence and development of gastric cancer.
