Background Histone deacetylase inhibitors （HDACIs） have been reported to induce apoptosis in cancer cells. The effects of trichostatin A （TSA） on gastric cancer cells have not been well characterized. This study w...Background Histone deacetylase inhibitors （HDACIs） have been reported to induce apoptosis in cancer cells. The effects of trichostatin A （TSA） on gastric cancer cells have not been well characterized. This study was aimed to explore the effects and mechanisms of TSA on human gastric cancer SGC-7901 cells. Methods The cells were treated with TSA and analyzed by cell proliferation assay, Western blot, TUNEL assay, flow cytometry by fluorescein isothiocyanate （FITC） conjugated with Annexin V and PI staining, immunofluorescence analysis, analysis of subcellular fractionation, gene chips and real time polymerase chain reaction （PCR）. Results TSA could inhibit cell growth and induced apoptosis in gastric cancer SGC-7901 cells through the regulation of apoptosis-related genes, such as Bcl-2, Bax and survivin. Further study indicated that the pan-caspase inhibitor z-VAD-fmk did not inhibit the apoptosis induced by TSA, and we did not observe the cleavage of poly ADP ribose polymerase （PARP） after TSA treatment too. In addition, apoptosis inducing factor （AIF） and EndoG were found to translocate from mitochondria to nucleus in the immunofluorescence assay and the Western analysis of subcellular fractionation confirmed the result of immunofluorescence assay. Conclusions The apoptosis induced by TSA in gastric cancer SGC-7901 cells involves a caspase-independent pathway.展开更多
Insufficient epigenetic reprogramming of donor nuclei is believed to be one of the most important causes of low development efficiency of mammalian somatic cell nuclear transfer （SCNT）. Previous studies have shown t...Insufficient epigenetic reprogramming of donor nuclei is believed to be one of the most important causes of low development efficiency of mammalian somatic cell nuclear transfer （SCNT）. Previous studies have shown that both the in vitro and in vivo development of mouse SCNT embryos could be increased significantly by treat- ment with various histone deacetylase inhibitors （HDACi）, including Trichostatin A, Scriptaid, and m-carboxycin- namic acid bishydroxamide （CBHA）, in which only the effect of CBHA has not yet been tested in other species. In this paper we examine the effect of CBHA treatment on the development of porcine SCNT embryos. We have dis- covered the optimum dosage and time for CBHA treat- ment： incubating SCNT embryos with 2 pmol/L CBHA for 24 h after activation could increase the blastocyst rate from 12.7% to 26.5%. Immunofluorescence results showed that the level of acetylation at histone 3 lysine 9 （AcH3K9）, acetylation at histone 3 lysine 18 （AcH3K18）, and acetylation at histone 4 lysine 16 （AcH4K16） was raised after CBHA treatment. Meanwhile, CBHA treatment improved the expression of development relating genes such as pou5fl, cdx2, and the imprinted genes like igf2. Despite these promising in vitro results and histone reprogramming, the full term development was notsignificantly increased after treatment. In conclusion, CBHA improves the in vitro development of pig SCNT embryos, increases the global histone acetylation and corrects the expression of some developmentally important genes at early stages. As in mouse SCNT, we have shown that nuclear epigenetic reprogramming in pig early SCNT embryos can be modified by CBHA treatment.展开更多
文摘Background Histone deacetylase inhibitors （HDACIs） have been reported to induce apoptosis in cancer cells. The effects of trichostatin A （TSA） on gastric cancer cells have not been well characterized. This study was aimed to explore the effects and mechanisms of TSA on human gastric cancer SGC-7901 cells. Methods The cells were treated with TSA and analyzed by cell proliferation assay, Western blot, TUNEL assay, flow cytometry by fluorescein isothiocyanate （FITC） conjugated with Annexin V and PI staining, immunofluorescence analysis, analysis of subcellular fractionation, gene chips and real time polymerase chain reaction （PCR）. Results TSA could inhibit cell growth and induced apoptosis in gastric cancer SGC-7901 cells through the regulation of apoptosis-related genes, such as Bcl-2, Bax and survivin. Further study indicated that the pan-caspase inhibitor z-VAD-fmk did not inhibit the apoptosis induced by TSA, and we did not observe the cleavage of poly ADP ribose polymerase （PARP） after TSA treatment too. In addition, apoptosis inducing factor （AIF） and EndoG were found to translocate from mitochondria to nucleus in the immunofluorescence assay and the Western analysis of subcellular fractionation confirmed the result of immunofluorescence assay. Conclusions The apoptosis induced by TSA in gastric cancer SGC-7901 cells involves a caspase-independent pathway.
文摘Insufficient epigenetic reprogramming of donor nuclei is believed to be one of the most important causes of low development efficiency of mammalian somatic cell nuclear transfer （SCNT）. Previous studies have shown that both the in vitro and in vivo development of mouse SCNT embryos could be increased significantly by treat- ment with various histone deacetylase inhibitors （HDACi）, including Trichostatin A, Scriptaid, and m-carboxycin- namic acid bishydroxamide （CBHA）, in which only the effect of CBHA has not yet been tested in other species. In this paper we examine the effect of CBHA treatment on the development of porcine SCNT embryos. We have dis- covered the optimum dosage and time for CBHA treat- ment： incubating SCNT embryos with 2 pmol/L CBHA for 24 h after activation could increase the blastocyst rate from 12.7% to 26.5%. Immunofluorescence results showed that the level of acetylation at histone 3 lysine 9 （AcH3K9）, acetylation at histone 3 lysine 18 （AcH3K18）, and acetylation at histone 4 lysine 16 （AcH4K16） was raised after CBHA treatment. Meanwhile, CBHA treatment improved the expression of development relating genes such as pou5fl, cdx2, and the imprinted genes like igf2. Despite these promising in vitro results and histone reprogramming, the full term development was notsignificantly increased after treatment. In conclusion, CBHA improves the in vitro development of pig SCNT embryos, increases the global histone acetylation and corrects the expression of some developmentally important genes at early stages. As in mouse SCNT, we have shown that nuclear epigenetic reprogramming in pig early SCNT embryos can be modified by CBHA treatment.
