Background:Alterations in splicing factors contribute to aberrant alternative splicing(AS),which subsequently promotes tumor progression.The splicing factor polypyrimidine tract binding protein 1(PTBP1)has been shown ...Background:Alterations in splicing factors contribute to aberrant alternative splicing(AS),which subsequently promotes tumor progression.The splicing factor polypyrimidine tract binding protein 1(PTBP1)has been shown to facilitate cancer progression by modulating oncogenic variants.However,its specific role and underlying mechanisms in hepatocellular carcinoma(HCC)remain to be elucidated.Methods:PTBP1 expression was evaluated in HCC tissues and cell lines.Subsequently,cells were transfected with vectors designed for PTBP1 overexpression or downregulation.The biological function of PTBP1 was assessed in vitro and in vivo using MTS assays,colony formation assays,transwell assays,xenograft formation,tail vein injection,and orthotopic models.Transcriptome analysis was conducted to elucidate the underlying molecular mechanisms.Results:Our findings demonstrated that PTBP1 exhibited elevated expression in HCC cell lines and tissues.Furthermore,its expression positively correlated with overall and disease-free survival rates,as well as tumor grade and stage.PTBP1 knockdown reduced HCC cell proliferation,migration,and invasion in vitro and suppressed hepatocarcinoma xenograft growth and infiltration in vivo.RNA sequencing(RNA-Seq)analysis identified the AS events associated with PTBP1.PTBP1 functionally enhanced cell proliferation,invasion,and migration by modulating the AS of the microtubule-associated protein tau(MAPT)gene and promoting oncogene expression.Notably,the dysregulation of MAPT splicing coincided with increased PTBP1 expression in HCC.Conclusions:PTBP1-guided AS of the MAPT gene enhances tumorigenicity in HCC through activation of the MAPK/ERK pathways.展开更多
Polypyrimidine tract-binding protein 1(PTBP1)plays an essential role in splicing and is expressed in almost all cell types in humans,unlike the other proteins of the PTBP family.PTBP1 mediates several cellular process...Polypyrimidine tract-binding protein 1(PTBP1)plays an essential role in splicing and is expressed in almost all cell types in humans,unlike the other proteins of the PTBP family.PTBP1 mediates several cellular processes in certain types of cells,including the growth and differentiation of neuronal cells and activation of immune cells.Its function is regulated by various molecules,including micro RNAs(mi RNAs),long non-coding RNAs(lnc RNAs),and RNA-binding proteins.PTBP1 plays roles in various diseases,particularly in some cancers,including colorectal cancer,renal cell cancer,breast cancer,and glioma.In cancers,it acts mainly as a regulator of glycolysis,apoptosis,proliferation,tumorigenesis,invasion,and migration.The role of PTBP1 in cancer has become a popular research topic in recent years,and this research has contributed greatly to the formulation of a useful therapeutic strategy for cancer.In this review,we summarize recent findings related to PTBP1 and discuss how it regulates the development of cancer cells.展开更多
[目的]探讨miR-330-5p/PTBP1/CTTN轴调控结肠癌细胞凋亡的潜在机制。[方法]纳入接受根治性结肠切除术的结肠癌患者113例,分析miR-330-5p在结肠癌组织和癌旁组织中的表达水平以及其对总生存率的影响。[结果]miR-330-5p在结肠癌组织中的...[目的]探讨miR-330-5p/PTBP1/CTTN轴调控结肠癌细胞凋亡的潜在机制。[方法]纳入接受根治性结肠切除术的结肠癌患者113例,分析miR-330-5p在结肠癌组织和癌旁组织中的表达水平以及其对总生存率的影响。[结果]miR-330-5p在结肠癌组织中的表达水平较低(0.48±0.22 vs 0.16±0.09,P<0.05)。miR-330-5p高表达的结肠癌患者具有更高的总生存率。过表达miR-330-5p及敲低PTBP1,HCT116细胞的凋亡水平上升(13.02±2.11 vs 68.41±11.08, 12.84±2.16 vs 59.12±10.53,P<0.05)。过表达miR-330-5p后,HCT116细胞中PTBP1的mRNA水平和蛋白水平均下降(0.39±0.04 vs 0.05±0.01,P<0.05)。敲低CTTN后,HCTT6细胞的凋亡水平显著上升(11.70±2.05 vs 55.73±10.19,P<0.05)。过表达miR-330-5p或PTBP1敲低后,CTTN isoform a的表达水平下降。[结论]miR-330-5p能够靶向降解PTBP1 mRNA,减少PTBP1的表达水平,促进结肠癌细胞凋亡。miR-330-5p/PTBP1轴能够调控CTTN外显子的选择性剪接,抑制CTTN isoform a的表达水平并促进结肠癌细胞凋亡。展开更多
基金supported by the National Natural Science Foundation of China(Nos.81972771,82173062)the Key Areas Project of Education Department of Guangdong Province(No.2021ZDZX2017)+3 种基金the Tertiary Education Scientific Research Project of Guangzhou Municipal Education Bureau(No.202235387)the Guangzhou Science and Technology Project of Guangzhou Municipal Science and Technology Bureau(No.2023A03J0428)the Natural Science Foundation of Guangdong Province,China(No.2024A1515013082)the Guangdong Basic and Applied Basic Research 21 Foundation(No.2021A1515010403).
文摘Background:Alterations in splicing factors contribute to aberrant alternative splicing(AS),which subsequently promotes tumor progression.The splicing factor polypyrimidine tract binding protein 1(PTBP1)has been shown to facilitate cancer progression by modulating oncogenic variants.However,its specific role and underlying mechanisms in hepatocellular carcinoma(HCC)remain to be elucidated.Methods:PTBP1 expression was evaluated in HCC tissues and cell lines.Subsequently,cells were transfected with vectors designed for PTBP1 overexpression or downregulation.The biological function of PTBP1 was assessed in vitro and in vivo using MTS assays,colony formation assays,transwell assays,xenograft formation,tail vein injection,and orthotopic models.Transcriptome analysis was conducted to elucidate the underlying molecular mechanisms.Results:Our findings demonstrated that PTBP1 exhibited elevated expression in HCC cell lines and tissues.Furthermore,its expression positively correlated with overall and disease-free survival rates,as well as tumor grade and stage.PTBP1 knockdown reduced HCC cell proliferation,migration,and invasion in vitro and suppressed hepatocarcinoma xenograft growth and infiltration in vivo.RNA sequencing(RNA-Seq)analysis identified the AS events associated with PTBP1.PTBP1 functionally enhanced cell proliferation,invasion,and migration by modulating the AS of the microtubule-associated protein tau(MAPT)gene and promoting oncogene expression.Notably,the dysregulation of MAPT splicing coincided with increased PTBP1 expression in HCC.Conclusions:PTBP1-guided AS of the MAPT gene enhances tumorigenicity in HCC through activation of the MAPK/ERK pathways.
基金Project supported by the National Natural Science Foundation of China(Nos.81773179,81272972,and 81472355)the Program for New Century Excellent Talents in University(No.NCET-10-0790)+2 种基金the Hunan Provincial Science and Technology Department(Nos.2016JC 2049 and 2014FJ6006)the Hunan Provincial Natural Science Foundation of China(No.2016JJ2172)the Undergraduate Training Programs for Innovation and Entrepreneurship(Nos.201810533368,GS201910533474,and GS201910533236),China.
文摘Polypyrimidine tract-binding protein 1(PTBP1)plays an essential role in splicing and is expressed in almost all cell types in humans,unlike the other proteins of the PTBP family.PTBP1 mediates several cellular processes in certain types of cells,including the growth and differentiation of neuronal cells and activation of immune cells.Its function is regulated by various molecules,including micro RNAs(mi RNAs),long non-coding RNAs(lnc RNAs),and RNA-binding proteins.PTBP1 plays roles in various diseases,particularly in some cancers,including colorectal cancer,renal cell cancer,breast cancer,and glioma.In cancers,it acts mainly as a regulator of glycolysis,apoptosis,proliferation,tumorigenesis,invasion,and migration.The role of PTBP1 in cancer has become a popular research topic in recent years,and this research has contributed greatly to the formulation of a useful therapeutic strategy for cancer.In this review,we summarize recent findings related to PTBP1 and discuss how it regulates the development of cancer cells.
文摘[目的]探讨miR-330-5p/PTBP1/CTTN轴调控结肠癌细胞凋亡的潜在机制。[方法]纳入接受根治性结肠切除术的结肠癌患者113例,分析miR-330-5p在结肠癌组织和癌旁组织中的表达水平以及其对总生存率的影响。[结果]miR-330-5p在结肠癌组织中的表达水平较低(0.48±0.22 vs 0.16±0.09,P<0.05)。miR-330-5p高表达的结肠癌患者具有更高的总生存率。过表达miR-330-5p及敲低PTBP1,HCT116细胞的凋亡水平上升(13.02±2.11 vs 68.41±11.08, 12.84±2.16 vs 59.12±10.53,P<0.05)。过表达miR-330-5p后,HCT116细胞中PTBP1的mRNA水平和蛋白水平均下降(0.39±0.04 vs 0.05±0.01,P<0.05)。敲低CTTN后,HCTT6细胞的凋亡水平显著上升(11.70±2.05 vs 55.73±10.19,P<0.05)。过表达miR-330-5p或PTBP1敲低后,CTTN isoform a的表达水平下降。[结论]miR-330-5p能够靶向降解PTBP1 mRNA,减少PTBP1的表达水平,促进结肠癌细胞凋亡。miR-330-5p/PTBP1轴能够调控CTTN外显子的选择性剪接,抑制CTTN isoform a的表达水平并促进结肠癌细胞凋亡。
