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
AIM:To develop a prognostic approach for gastrointestinal stromal tumors(GISTs) using a cluster of indicators and follow-up information.METHODS:One hundred and four GISTs that had not been subjected to targeted therap...AIM:To develop a prognostic approach for gastrointestinal stromal tumors(GISTs) using a cluster of indicators and follow-up information.METHODS:One hundred and four GISTs that had not been subjected to targeted therapies were collected and classified by NIH risk assessment and anatomic location.By immunohistochemistry,the expressions of PTEN,Ki-67,CD44s matrix metalloproteinase(MMP)-9 and TIMP-1 were detected on tissue microarray.Univariate and multimarker survival analyses were performed and then a COX hazard proportion model was constructed to evaluate a cluster of predictors of GIST.RESULTS:Our data showed small intestinal GIST are more aggressive than gastric GIST.The NIH risk assessment correlated with disease-free survival foreither gastric GIST or small intestinal GIST.Immunohistochemical analysis revealed that Ki-67 labeling indexes(LIs) < 5% predicted higher disease-specific survival(DSS) in gastric and small intestinal GIST.CD44s positivity and PTEN LIs ≥ 50% correlated with higher DSS in gastric GIST.MMP-9 and TIMP-1 had no correlation with survival.Multimarker analysis revealed that the expression pattern of PTEN LIs ≥ 50% combined with Ki-67 LIs < 5% and CD44s positivity reliably predicted favorable outcomes for gastric GIST(P = 0.009),as did the combination of PTEN LIs ≥ 50% and Ki-67 LIs < 5% for small intestinal GIST(P = 0.011).Authors also found that high NIH risk grade was correlated with DSS in patients with gastric GIST and disease-free survival in patients with small intestinal GIST.CONCLUSION:PTEN LIs ≥ 50%,Ki-67 LIs < 5% and CD44s positivity provides an accurate,favorable prognosis for gastric GIST.PTEN LIs ≥ 50% and Ki-67 LIs < 5% does the same for small intestinal GIST.Ki-67 LIs enhances the NIH assessment.展开更多
AIM:To investigate the effects of small interference RNA(siRNA) targeting of Cdx2 on human gastric cancer MGC-803 cells in vitro and in vivo.METHODS:The recombinant pSilencer 4.1-Cdx2 siRNA plasmids were constructed a...AIM:To investigate the effects of small interference RNA(siRNA) targeting of Cdx2 on human gastric cancer MGC-803 cells in vitro and in vivo.METHODS:The recombinant pSilencer 4.1-Cdx2 siRNA plasmids were constructed and transfected into gastric cancer MGC-803 cells in vitro.The stable transfectants were selected.The effects of Cdx2 siRNA on growth,proliferation,cell cycle,apoptosis,migration and invasiveness of human gastric cancer MGC-803 cells were evaluated and the expression of phosphatase and tensin homolog(PTEN),caspase-9 and caspase-3 was observed in vitro by reverse transcription polymerase chain reaction(RT-PCR) and Western blotting analysis.We also investigated the effect of Cdx2 siRNA on growth of MGC-803 cells in nude mice in vivo.RESULTS:Cdx2 siRNA led to inhibition of endogenous Cdx2 mRNA and protein expression as determined by RT-PCR and Western blotting analysis.Cdx2 siRNA significantly inhibited cell growth and proliferation,blocked entry into the S-phase of the cell cycle,induced cell apoptosis,and reduced the motility and invasion of MGC-803 cells.Cdx2 siRNA also increased PTEN expression,and activated caspase-9 and caspase-3 in MGC-803 cells in vitro.In addition,siRNA targeting of Cdx2 inhibited the growth of MGC-803 cells and promoted tumor cell apoptosis in vivo in nude mice tumor models.CONCLUSION:Cdx2 was involved in regulating progression of human gastric cancer cells MGC-803.Manipulation of Cdx2 expression may be a potential therapeutic strategy for gastric cancer.展开更多
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.
基金Supported by Grants from the National Key Basic Research Program Project of China,No.2004CB518708National BioTech 863 program,No. 2002-BA711 A11
文摘AIM:To develop a prognostic approach for gastrointestinal stromal tumors(GISTs) using a cluster of indicators and follow-up information.METHODS:One hundred and four GISTs that had not been subjected to targeted therapies were collected and classified by NIH risk assessment and anatomic location.By immunohistochemistry,the expressions of PTEN,Ki-67,CD44s matrix metalloproteinase(MMP)-9 and TIMP-1 were detected on tissue microarray.Univariate and multimarker survival analyses were performed and then a COX hazard proportion model was constructed to evaluate a cluster of predictors of GIST.RESULTS:Our data showed small intestinal GIST are more aggressive than gastric GIST.The NIH risk assessment correlated with disease-free survival foreither gastric GIST or small intestinal GIST.Immunohistochemical analysis revealed that Ki-67 labeling indexes(LIs) < 5% predicted higher disease-specific survival(DSS) in gastric and small intestinal GIST.CD44s positivity and PTEN LIs ≥ 50% correlated with higher DSS in gastric GIST.MMP-9 and TIMP-1 had no correlation with survival.Multimarker analysis revealed that the expression pattern of PTEN LIs ≥ 50% combined with Ki-67 LIs < 5% and CD44s positivity reliably predicted favorable outcomes for gastric GIST(P = 0.009),as did the combination of PTEN LIs ≥ 50% and Ki-67 LIs < 5% for small intestinal GIST(P = 0.011).Authors also found that high NIH risk grade was correlated with DSS in patients with gastric GIST and disease-free survival in patients with small intestinal GIST.CONCLUSION:PTEN LIs ≥ 50%,Ki-67 LIs < 5% and CD44s positivity provides an accurate,favorable prognosis for gastric GIST.PTEN LIs ≥ 50% and Ki-67 LIs < 5% does the same for small intestinal GIST.Ki-67 LIs enhances the NIH assessment.
基金Supported by Grants from the Natural Science Foundation of China,No.81060201 and No.81060277the Higher School Specialized Research Foundation for the Doctoral Program of China,No.20114503110002+1 种基金the Postdoctoral Science Foundation of China,No.201003342the Natural Science Foundation of Guangxi,No.2011GXNSFA018273
文摘AIM:To investigate the effects of small interference RNA(siRNA) targeting of Cdx2 on human gastric cancer MGC-803 cells in vitro and in vivo.METHODS:The recombinant pSilencer 4.1-Cdx2 siRNA plasmids were constructed and transfected into gastric cancer MGC-803 cells in vitro.The stable transfectants were selected.The effects of Cdx2 siRNA on growth,proliferation,cell cycle,apoptosis,migration and invasiveness of human gastric cancer MGC-803 cells were evaluated and the expression of phosphatase and tensin homolog(PTEN),caspase-9 and caspase-3 was observed in vitro by reverse transcription polymerase chain reaction(RT-PCR) and Western blotting analysis.We also investigated the effect of Cdx2 siRNA on growth of MGC-803 cells in nude mice in vivo.RESULTS:Cdx2 siRNA led to inhibition of endogenous Cdx2 mRNA and protein expression as determined by RT-PCR and Western blotting analysis.Cdx2 siRNA significantly inhibited cell growth and proliferation,blocked entry into the S-phase of the cell cycle,induced cell apoptosis,and reduced the motility and invasion of MGC-803 cells.Cdx2 siRNA also increased PTEN expression,and activated caspase-9 and caspase-3 in MGC-803 cells in vitro.In addition,siRNA targeting of Cdx2 inhibited the growth of MGC-803 cells and promoted tumor cell apoptosis in vivo in nude mice tumor models.CONCLUSION:Cdx2 was involved in regulating progression of human gastric cancer cells MGC-803.Manipulation of Cdx2 expression may be a potential therapeutic strategy for gastric cancer.
