Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten （PTEN） gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely ...Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten （PTEN） gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely used, greatly simplifies preparation of recombinant adenovirus. Therefore, recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene （Ad-PTEN） was constructed using the AdEasy-1 system and was transfected into HEK293 cells for packaging and amplification. Infection efficiency and expression intensity were observed in primary cultured rat hippocampal neurons infected with Ad-PTEN in vitro. Results revealed a cytopathic effect in green fluorescent protein expression, which increased with prolonged time. After three cycles of amplification, the adenovirus titer was increased to an adequate titer for infecting hippocampal neurons. The entire process typically requires 4-5 weeks for completion. Results suggested that recombinant defective adenovirus vector carrying the PTEN gene was successfully and rapidly constructed using the AdEasy system.展开更多
To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein express...To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein expression in the patients with human colorectal adenomas and adenocarcinomas.Methods The expression of PTEN,HIF-1 alpha gene was detected by using in situ hybridization,and the VEGF expression levels by immunohistochemistry in colorectal adenomas and primary colorectal adenocarcinoma.Results Strong expression of HIF-1 alpha was detectable in the majority of colorectal dadenocarcinoma,particularly surrounding areas of necrosis in adenocarcinoma.PTEN,HIF-1 alpha mRNA and VEGF protein were positive in 51.6%,67.7% and 59.7% respectively in 62 cases of adenocarcinomas,and 77.8%,44.4% and 33.3% respectively in 18 cases of adenomas.The positive rate of VEGF was higher in the patients with colorectal adenocarcinomas than that in those with adenomas,whereas that of PTEN mRNA was contrary.HIF-1 mRNA expression was correlated significantly with lymph node metastasis,liver metastasis,Duke’s stage and recurrence.During colorectal tumor progression,the expression of HIF-1 alpha mRNA was positively correlated with the VEGF protein expression (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=21.84,P<0.01).Conclusion The absence or low expression of PTEN and the increased levels of HIF-1α and VEGF may paly an important role in carcinogenesis and progression of colorectal carcinoma.These results suggest that VEGF upregulated by HIF-1 alpha gene may be involved in angiogenesis of colorectal adenocarcinoma.4 refs,1 tab.展开更多
Although significant progress has been made in the development of novel targeted drugs for the treatment of acute myeloid leukemia(AML)in recent years,chemotherapy still remains the mainstay of treatment and the overa...Although significant progress has been made in the development of novel targeted drugs for the treatment of acute myeloid leukemia(AML)in recent years,chemotherapy still remains the mainstay of treatment and the overall survival is poor in most patients.Here,we demonstrated the antileukemia activity of a novel small molecular compound NL101,which is formed through the modification on bendamustine with a suberanilohydroxamic acid(SAHA)radical.NL101 suppresses the proliferation of myeloid malignancy cells and primary AML cells.It induces DNA damage and caspase 3-mediated apoptosis.A genome-wide clustered regularly interspaced short palindromic repeats(CRISPR)library screen revealed that phosphatase and tensin homologous(PTEN)gene is critical for the regulation of cell survival upon NL101 treatment.The knockout or inhibition of PTEN significantly reduced NL101-induced apoptosis in AML and myelodysplastic syndrome(MDS)cells,accompanied by the activation of protein kinase B(AKT)signaling pathway.The inhibition of mammalian target of rapamycin(mTOR)by rapamycin enhanced the sensitivity of AML cells to NL101-induced cell death.These findings uncover PTEN protein expression as a major determinant of chemosensitivity to NL101 and provide a novel strategy to treat AML with the combination of NL101 and rapamycin.展开更多
Background： Apoptosis of endothelial cells （ECs） plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 （PTEN） is...Background： Apoptosis of endothelial cells （ECs） plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 （PTEN） is a viable target in therapeutic approaches to prevent vascular ECs apoptosis. Aberrant miR-106b-5p expression has been reported in the plasma of patients with unstable atherosclerotic plaques. However, the role and underlying mechanism of miR-106-5p in the genesis of atherosclerosis have not been addressed. In this study, we explored the anti-apoptotic role of miR-106-5p by regulating PTEN expression in vascular ECs. Methods： Real-time reverse transcription polymerase chain reaction （RT-PCR） was performed to detect the expression levels of miR-106b-5p in human atherosclerotic plaques and normal vascular tissues. Human umbilical vein endothelial cells （HUVEC） were transfected with miR-106b-5p mimic or negative control mimic, and apoptosis was induced by serum starvation and tumor necrosis factor-α （TN F-α） treat. Western blotting and real-time RT-PCR experiments were used to detect PTEN expression levels and TN F-α-induced apoptosis was evaluated by the activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Results： The expression ofmiR-106b-5p was significantly downregulated in plaques than in normal vascular tissues. TNF-α significantly downregulated miR-106b-5p expression levels and upregulated activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Overexpression ofmiR-106b-5p with miR-106b-5p mimic inhibited PTEN expression and TNF-α-induced apoptosis in HUVEC. Luciferase reporter assays confirmed that miR-106b-5p binds to PTEN mRNA 3＇ untranslated region site, Conclusion： MiR-106b-5p could inhibit the expression of PTEN in vascular ECs, which could block TNF-α-induced activation of caspase-3, thus prevent ECs apoptosis in atherosclerosis diseases.展开更多
人第10号染色体缺失的磷酸酶及张力蛋白同源(phosphatase and tensin homolog deleted on chromosome ten,PTEN)基因作为一种抑癌基因,在调控肿瘤方面的作用广为人知。近年来研究发现,PTEN除了在肿瘤防治上发挥作用外,还能通过抑制炎症...人第10号染色体缺失的磷酸酶及张力蛋白同源(phosphatase and tensin homolog deleted on chromosome ten,PTEN)基因作为一种抑癌基因,在调控肿瘤方面的作用广为人知。近年来研究发现,PTEN除了在肿瘤防治上发挥作用外,还能通过抑制炎症、氧化应激的发展来减缓动脉粥样硬化(atherosclerosis,AS)的进程。同时,PTEN蛋白能够抑制AS中血管平滑肌细胞(vascular smooth muscle cells,VSMCs)的异常增殖,以及调控巨噬细胞极化的方向、改变巨噬细胞表面清道夫受体的类型来抗AS。而PTEN对于血管内皮细胞(vascular endothelial cells,VECs)的调控则具有双重性。文章对PTEN的结构、功能与发挥的调控作用做一简要综述,以期为AS防治的基础研究提供新的思路和靶点。展开更多
目的研究PTEN基因与宫颈癌细胞增殖能力的关系,以探索PTEN基因在宫颈癌发生发展中的可能作用及其机制。方法 Western blot检测PTEN基因在宫颈癌细胞系HeLa、SiHa、C33A和CasKi中的表达。利用脂质体法将人工过表达PTEN载体转染低表达PTE...目的研究PTEN基因与宫颈癌细胞增殖能力的关系,以探索PTEN基因在宫颈癌发生发展中的可能作用及其机制。方法 Western blot检测PTEN基因在宫颈癌细胞系HeLa、SiHa、C33A和CasKi中的表达。利用脂质体法将人工过表达PTEN载体转染低表达PTEN的宫颈癌细胞系HeLa和C33A,通过MTT方法观察转染后PTEN过表达对宫颈癌细胞增殖的影响。采用多功能过程参数分析仪,检测转染PTEN基因后宫颈癌细胞培养基中乳酸、葡萄糖及谷氨酰胺的含量,观察PTEN基因过表达对宫颈癌细胞代谢的影响。Western blot检测PTEN过表达后宫颈癌细胞中丙酮酸激酶(PKM2)、6-磷酸果糖激酶2(PFKFB3)、谷氨酰胺酶(GLS)、AKT和磷酸化的AKT(pAKT)表达情况。结果与正常宫颈上皮细胞相比,PTEN基因在4种宫颈癌细胞系中低表达。与对照组相比,过表达PTEN的HeLa和C33A细胞克隆中,PTEN基因的水平明显升高。细胞计数和MTT法也显示,过表达PTEN能够明显抑制肿瘤细胞的增殖速率(P<0.05);过表达PTEN基因的细胞培养液中葡萄糖及谷氨酰胺含量显著增多,但乳酸含量减少;同时还发现PTEN抑制了AKT的磷酸化水平并使PKM2、PFKFB3及GLS的表达水平降低。结论 PTEN基因可通过AKT途径调节细胞代谢,从而调节宫颈癌细胞的增殖。PTEN基因有可能成为宫颈癌的诊断和治疗的新靶点。展开更多
文摘Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten （PTEN） gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely used, greatly simplifies preparation of recombinant adenovirus. Therefore, recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene （Ad-PTEN） was constructed using the AdEasy-1 system and was transfected into HEK293 cells for packaging and amplification. Infection efficiency and expression intensity were observed in primary cultured rat hippocampal neurons infected with Ad-PTEN in vitro. Results revealed a cytopathic effect in green fluorescent protein expression, which increased with prolonged time. After three cycles of amplification, the adenovirus titer was increased to an adequate titer for infecting hippocampal neurons. The entire process typically requires 4-5 weeks for completion. Results suggested that recombinant defective adenovirus vector carrying the PTEN gene was successfully and rapidly constructed using the AdEasy system.
文摘To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein expression in the patients with human colorectal adenomas and adenocarcinomas.Methods The expression of PTEN,HIF-1 alpha gene was detected by using in situ hybridization,and the VEGF expression levels by immunohistochemistry in colorectal adenomas and primary colorectal adenocarcinoma.Results Strong expression of HIF-1 alpha was detectable in the majority of colorectal dadenocarcinoma,particularly surrounding areas of necrosis in adenocarcinoma.PTEN,HIF-1 alpha mRNA and VEGF protein were positive in 51.6%,67.7% and 59.7% respectively in 62 cases of adenocarcinomas,and 77.8%,44.4% and 33.3% respectively in 18 cases of adenomas.The positive rate of VEGF was higher in the patients with colorectal adenocarcinomas than that in those with adenomas,whereas that of PTEN mRNA was contrary.HIF-1 mRNA expression was correlated significantly with lymph node metastasis,liver metastasis,Duke’s stage and recurrence.During colorectal tumor progression,the expression of HIF-1 alpha mRNA was positively correlated with the VEGF protein expression (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=21.84,P<0.01).Conclusion The absence or low expression of PTEN and the increased levels of HIF-1α and VEGF may paly an important role in carcinogenesis and progression of colorectal carcinoma.These results suggest that VEGF upregulated by HIF-1 alpha gene may be involved in angiogenesis of colorectal adenocarcinoma.4 refs,1 tab.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY21H080005)the National Natural Science Foundation of China(Nos.81572920 and 82100171).
文摘Although significant progress has been made in the development of novel targeted drugs for the treatment of acute myeloid leukemia(AML)in recent years,chemotherapy still remains the mainstay of treatment and the overall survival is poor in most patients.Here,we demonstrated the antileukemia activity of a novel small molecular compound NL101,which is formed through the modification on bendamustine with a suberanilohydroxamic acid(SAHA)radical.NL101 suppresses the proliferation of myeloid malignancy cells and primary AML cells.It induces DNA damage and caspase 3-mediated apoptosis.A genome-wide clustered regularly interspaced short palindromic repeats(CRISPR)library screen revealed that phosphatase and tensin homologous(PTEN)gene is critical for the regulation of cell survival upon NL101 treatment.The knockout or inhibition of PTEN significantly reduced NL101-induced apoptosis in AML and myelodysplastic syndrome(MDS)cells,accompanied by the activation of protein kinase B(AKT)signaling pathway.The inhibition of mammalian target of rapamycin(mTOR)by rapamycin enhanced the sensitivity of AML cells to NL101-induced cell death.These findings uncover PTEN protein expression as a major determinant of chemosensitivity to NL101 and provide a novel strategy to treat AML with the combination of NL101 and rapamycin.
基金This research was funded by the National Natural Science Foundation of China (NSFC)
文摘Background： Apoptosis of endothelial cells （ECs） plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 （PTEN） is a viable target in therapeutic approaches to prevent vascular ECs apoptosis. Aberrant miR-106b-5p expression has been reported in the plasma of patients with unstable atherosclerotic plaques. However, the role and underlying mechanism of miR-106-5p in the genesis of atherosclerosis have not been addressed. In this study, we explored the anti-apoptotic role of miR-106-5p by regulating PTEN expression in vascular ECs. Methods： Real-time reverse transcription polymerase chain reaction （RT-PCR） was performed to detect the expression levels of miR-106b-5p in human atherosclerotic plaques and normal vascular tissues. Human umbilical vein endothelial cells （HUVEC） were transfected with miR-106b-5p mimic or negative control mimic, and apoptosis was induced by serum starvation and tumor necrosis factor-α （TN F-α） treat. Western blotting and real-time RT-PCR experiments were used to detect PTEN expression levels and TN F-α-induced apoptosis was evaluated by the activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Results： The expression ofmiR-106b-5p was significantly downregulated in plaques than in normal vascular tissues. TNF-α significantly downregulated miR-106b-5p expression levels and upregulated activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Overexpression ofmiR-106b-5p with miR-106b-5p mimic inhibited PTEN expression and TNF-α-induced apoptosis in HUVEC. Luciferase reporter assays confirmed that miR-106b-5p binds to PTEN mRNA 3＇ untranslated region site, Conclusion： MiR-106b-5p could inhibit the expression of PTEN in vascular ECs, which could block TNF-α-induced activation of caspase-3, thus prevent ECs apoptosis in atherosclerosis diseases.
文摘目的研究PTEN基因与宫颈癌细胞增殖能力的关系,以探索PTEN基因在宫颈癌发生发展中的可能作用及其机制。方法 Western blot检测PTEN基因在宫颈癌细胞系HeLa、SiHa、C33A和CasKi中的表达。利用脂质体法将人工过表达PTEN载体转染低表达PTEN的宫颈癌细胞系HeLa和C33A,通过MTT方法观察转染后PTEN过表达对宫颈癌细胞增殖的影响。采用多功能过程参数分析仪,检测转染PTEN基因后宫颈癌细胞培养基中乳酸、葡萄糖及谷氨酰胺的含量,观察PTEN基因过表达对宫颈癌细胞代谢的影响。Western blot检测PTEN过表达后宫颈癌细胞中丙酮酸激酶(PKM2)、6-磷酸果糖激酶2(PFKFB3)、谷氨酰胺酶(GLS)、AKT和磷酸化的AKT(pAKT)表达情况。结果与正常宫颈上皮细胞相比,PTEN基因在4种宫颈癌细胞系中低表达。与对照组相比,过表达PTEN的HeLa和C33A细胞克隆中,PTEN基因的水平明显升高。细胞计数和MTT法也显示,过表达PTEN能够明显抑制肿瘤细胞的增殖速率(P<0.05);过表达PTEN基因的细胞培养液中葡萄糖及谷氨酰胺含量显著增多,但乳酸含量减少;同时还发现PTEN抑制了AKT的磷酸化水平并使PKM2、PFKFB3及GLS的表达水平降低。结论 PTEN基因可通过AKT途径调节细胞代谢,从而调节宫颈癌细胞的增殖。PTEN基因有可能成为宫颈癌的诊断和治疗的新靶点。
