The dysregulation of exosomal microRNAs(miRNAs)plays a crucial role in the development and progression of cancer.This study investigated the role of a newly identified serum exosomal miRNA miR-4256 in gastric cancer(G...The dysregulation of exosomal microRNAs(miRNAs)plays a crucial role in the development and progression of cancer.This study investigated the role of a newly identified serum exosomal miRNA miR-4256 in gastric cancer(GC)and the underlying mechanisms.The differentially expressed miRNAs were firstly identified in serum exosomes of GC patients and healthy individuals using next-generation sequencing and bioinformatics.Next,the expression of serum exosomal miR-4256 was analyzed in GC cells and GC tissues,and the role of miR-4256 in GC was investigated by in vitro and in vivo experiments.Then,the effect of miR-4256 on its downstream target genes HDAC5/p16^(INK4a) was studied in GC cells,and the underlying mechanisms were evaluated using dual luciferase reporter assay and Chromatin Immunoprecipitation(ChIP).Additionally,the role of the miR-4256/HDAC5/p16^(INK4a) axis in GC was studied using in vitro and in vivo experiments.Finally,the upstream regulators SMAD2/p300 that regulate miR-4256 expression and their role in GC were explored using in vitro experiments.miR-4256 was the most significantly upregulated miRNA and was overexpressed in GC cell lines and GC tissues;in vitro and in vivo results showed that miR-4256 promoted GC growth and progression.Mechanistically,miR-4256 enhanced HDAC5 expression by targeting the promoter of the HDAC5 gene in GC cells,and then restrained the expression of p16^(INK4a) through the epigenetic modulation of HDAC5 at the p16INK4a promoter.Furthermore,miR-4256 overexpression was positively regulated by the SMAD2/p300 complex in GC cells.Our data indicate that miR-4256 functions as an oncogene in GC via the SMAD2/miR-4256/HDAC5/p16^(INK4a) axis,which participates in GC progression and provides novel therapeutic and prognostic biomarkers for GC.展开更多
Objective: To evaluate the expression of p16INK4A gene in ovarian cancer and analyze the relation between this alteration and the promoter methylation of p16INK4A DNA. Methods: Seven ovarian cancer cell lines and ei...Objective: To evaluate the expression of p16INK4A gene in ovarian cancer and analyze the relation between this alteration and the promoter methylation of p16INK4A DNA. Methods: Seven ovarian cancer cell lines and eighteen ovarian cancer specimens were selected for the study. Genomic DNA and RNA were extracted from fresh tissues and cell lines, DNA was treated with sodium bisulfite and then analyzed with methylation-specific PCR (MSP) to detect p16INK4A methylation. The expression of p16INK4A mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR). In addition, the proliferation of methylated cell lines before and after treatment of demethylating agent 5-Aza-2'-deoxycytidine (5-ADC) was examined with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay in vivo. Results: Compared with the control, the expression of p16INK4A mRNA decreased significantly or absolutely defaulted in 10 of 18 (55.56%) ovarian cancer specimens and 71.4% (5/7) ovarian cancer cell lines (P〈0.05), and the expression of p16INK4A protein also decreased (P〈0.05). The decrease of p16INK4A was due, in part, to p16INK4A methylation, which was found in the first exon of three cell lines and six ovarian cancer specimens and the rate was 42.86% and 33.33% in ovarian cancer cell lines and specimens respectively. All the methylated cells and tissues showed expression defect of p16INK4A, but the treatment of 5-ADC reactivated the expression of p16INK4A in methylated cells and decreased the proliferation of tumor cells in vitro and in vivo. Conclusion: The expression defect of p16INK4A gene possibly has an important role in the development of ovarian cancer, and this alteration is due, in part, to the methylation of the first exon in p16INK4A.展开更多
INTRODUCTION Hepatocellular carcinoma(HCC)is the mostcommon cause of death from cancer in China.Themechanisms of hepatocarcinogenesis are not yetknown clearly,p16INK4a gene,the multiple tumorsuppressor gene 1(MTS1),en...INTRODUCTION Hepatocellular carcinoma(HCC)is the mostcommon cause of death from cancer in China.Themechanisms of hepatocarcinogenesis are not yetknown clearly,p16INK4a gene,the multiple tumorsuppressor gene 1(MTS1),encodes P16 protein,which acts as an inhibitor by binding directly toCDK4 and CDK6 and preventing its association展开更多
The effects of exogenous p16^ink4a gene on biological behaviors of human lung cancer cell line with homozygous deletion of p16^ink4a gene were investigated. Exogenous p16^ink4a gene was transfected by lipofectin into ...The effects of exogenous p16^ink4a gene on biological behaviors of human lung cancer cell line with homozygous deletion of p16^ink4a gene were investigated. Exogenous p16^ink4a gene was transfected by lipofectin into human lung cell line A549, in which p16^ink4a gene was homozygously deleted. The expression of p16^ink4a mRNA and protein was detected by RT-PCR and immunocytochemistry, respectively. The changes in the behaviors of the transfected cell lines in vitro and in vivo were observed. In the transfected cell line A549, the exogenous p16^ink4a gene could be stably expressed. The growth of A549 cells transfected with p16^ink4a gene was obviously slowed down. Flow cytometry revealed that transfection of the exogenous p16^ink4a gene resulted in A549 cell lines arrest in G1 phase of cell cycle. The tumorigenicity of these transfected cells in nude mice could be inhibited, and the tumor growth of nude mice was significantly suppressed. It was concluded that exogenous p16^ink4a gene may be stably expressed in human lung cancer cell line A549. The expression of the introduced p16^ink4a could block lung cancer cells to entry into S phase of cell cycle and inhibit tumor malignant growth both in vitro and in vivo.展开更多
目的:通过检测慢性宫颈炎(chronic cervicitis)、宫颈上皮内瘤变(cervical intraepithelial neoplasia,CIN)及宫颈鳞癌(squamous carcinoma of the cervix,SCC)组织中p16INK4A蛋白表达与人乳头瘤病毒(human papillomavirus,HPV)感染的状...目的:通过检测慢性宫颈炎(chronic cervicitis)、宫颈上皮内瘤变(cervical intraepithelial neoplasia,CIN)及宫颈鳞癌(squamous carcinoma of the cervix,SCC)组织中p16INK4A蛋白表达与人乳头瘤病毒(human papillomavirus,HPV)感染的状况,探讨p16INK4A蛋白和HPV感染与宫颈鳞癌发生发展的关系。方法:采用免疫组化PV-9000方法检测114例宫颈组织标本的p16INK4A表达,用核酸分子快速导流杂交基因芯片技术(HybriMax)检测21种HPV DNA。结果:(1)慢性宫颈炎、CINⅠ、CINⅡ、CINⅢ、SCC组织中p16INK4A蛋白表达阳性率分别为0%、45.83%、72.73%、84.00%、91.30%,随着宫颈病变程度加重,p16INK4A蛋白表达阳性率逐渐增高,表达强度增加,差异有统计学意义(P<0.05)。(2)慢性宫颈炎、CINI、CINⅡ、CINⅢ、SCC中HPV感染阳性率分别为20.00%、37.50%、54.55%、56.00%、73.91%,HPV感染在不同宫颈病变组织中差异有统计学意义(P<0.05)。随宫颈病变程度加重,HPV阳性率呈递增趋势,不同病变组织中位于前3位的HPV感染型别分别为:CINⅠ组,HPV16、18、58;CINⅡ~Ⅲ组,HPV16、33、52;宫颈鳞癌组,HPV16、18,52。(3)相关分析结果显示,病变组织中p16INK4A蛋白表达与HPV感染呈正相关(r=0.268,P<0.05)。结论:p16INK4A蛋白表达与宫颈病变程度有关,p16INK4A可能参与了HPV相关的宫颈癌发生。二者联合检测对宫颈癌筛查和预防具有重要意义。展开更多
基金The studies involving human participants were approved by The First Affiliated Hospital of Jinan University Ethics Committee(KY-2021-095)The participants provided their written informed consent to participate in this study+1 种基金Animalinvolved experimental protocols were compliance with guidelines and licensesapproved by the Laboratory Animal Center of Jinan University(20220225-65).
文摘The dysregulation of exosomal microRNAs(miRNAs)plays a crucial role in the development and progression of cancer.This study investigated the role of a newly identified serum exosomal miRNA miR-4256 in gastric cancer(GC)and the underlying mechanisms.The differentially expressed miRNAs were firstly identified in serum exosomes of GC patients and healthy individuals using next-generation sequencing and bioinformatics.Next,the expression of serum exosomal miR-4256 was analyzed in GC cells and GC tissues,and the role of miR-4256 in GC was investigated by in vitro and in vivo experiments.Then,the effect of miR-4256 on its downstream target genes HDAC5/p16^(INK4a) was studied in GC cells,and the underlying mechanisms were evaluated using dual luciferase reporter assay and Chromatin Immunoprecipitation(ChIP).Additionally,the role of the miR-4256/HDAC5/p16^(INK4a) axis in GC was studied using in vitro and in vivo experiments.Finally,the upstream regulators SMAD2/p300 that regulate miR-4256 expression and their role in GC were explored using in vitro experiments.miR-4256 was the most significantly upregulated miRNA and was overexpressed in GC cell lines and GC tissues;in vitro and in vivo results showed that miR-4256 promoted GC growth and progression.Mechanistically,miR-4256 enhanced HDAC5 expression by targeting the promoter of the HDAC5 gene in GC cells,and then restrained the expression of p16^(INK4a) through the epigenetic modulation of HDAC5 at the p16INK4a promoter.Furthermore,miR-4256 overexpression was positively regulated by the SMAD2/p300 complex in GC cells.Our data indicate that miR-4256 functions as an oncogene in GC via the SMAD2/miR-4256/HDAC5/p16^(INK4a) axis,which participates in GC progression and provides novel therapeutic and prognostic biomarkers for GC.
基金This work was supported by grant from the National Natural Science Foundation of China (No. 30070786)as well as Scientific and Technological Development Plan of Hubei Province of China
文摘Objective: To evaluate the expression of p16INK4A gene in ovarian cancer and analyze the relation between this alteration and the promoter methylation of p16INK4A DNA. Methods: Seven ovarian cancer cell lines and eighteen ovarian cancer specimens were selected for the study. Genomic DNA and RNA were extracted from fresh tissues and cell lines, DNA was treated with sodium bisulfite and then analyzed with methylation-specific PCR (MSP) to detect p16INK4A methylation. The expression of p16INK4A mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR). In addition, the proliferation of methylated cell lines before and after treatment of demethylating agent 5-Aza-2'-deoxycytidine (5-ADC) was examined with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay in vivo. Results: Compared with the control, the expression of p16INK4A mRNA decreased significantly or absolutely defaulted in 10 of 18 (55.56%) ovarian cancer specimens and 71.4% (5/7) ovarian cancer cell lines (P〈0.05), and the expression of p16INK4A protein also decreased (P〈0.05). The decrease of p16INK4A was due, in part, to p16INK4A methylation, which was found in the first exon of three cell lines and six ovarian cancer specimens and the rate was 42.86% and 33.33% in ovarian cancer cell lines and specimens respectively. All the methylated cells and tissues showed expression defect of p16INK4A, but the treatment of 5-ADC reactivated the expression of p16INK4A in methylated cells and decreased the proliferation of tumor cells in vitro and in vivo. Conclusion: The expression defect of p16INK4A gene possibly has an important role in the development of ovarian cancer, and this alteration is due, in part, to the methylation of the first exon in p16INK4A.
基金the National Natural Science Foundation of China,No.39670702
文摘INTRODUCTION Hepatocellular carcinoma(HCC)is the mostcommon cause of death from cancer in China.Themechanisms of hepatocarcinogenesis are not yetknown clearly,p16INK4a gene,the multiple tumorsuppressor gene 1(MTS1),encodes P16 protein,which acts as an inhibitor by binding directly toCDK4 and CDK6 and preventing its association
基金This project was supported by a grant from the Science Research Foundation of Hubei Province, China (No. 98J102).
文摘The effects of exogenous p16^ink4a gene on biological behaviors of human lung cancer cell line with homozygous deletion of p16^ink4a gene were investigated. Exogenous p16^ink4a gene was transfected by lipofectin into human lung cell line A549, in which p16^ink4a gene was homozygously deleted. The expression of p16^ink4a mRNA and protein was detected by RT-PCR and immunocytochemistry, respectively. The changes in the behaviors of the transfected cell lines in vitro and in vivo were observed. In the transfected cell line A549, the exogenous p16^ink4a gene could be stably expressed. The growth of A549 cells transfected with p16^ink4a gene was obviously slowed down. Flow cytometry revealed that transfection of the exogenous p16^ink4a gene resulted in A549 cell lines arrest in G1 phase of cell cycle. The tumorigenicity of these transfected cells in nude mice could be inhibited, and the tumor growth of nude mice was significantly suppressed. It was concluded that exogenous p16^ink4a gene may be stably expressed in human lung cancer cell line A549. The expression of the introduced p16^ink4a could block lung cancer cells to entry into S phase of cell cycle and inhibit tumor malignant growth both in vitro and in vivo.
文摘目的:通过检测慢性宫颈炎(chronic cervicitis)、宫颈上皮内瘤变(cervical intraepithelial neoplasia,CIN)及宫颈鳞癌(squamous carcinoma of the cervix,SCC)组织中p16INK4A蛋白表达与人乳头瘤病毒(human papillomavirus,HPV)感染的状况,探讨p16INK4A蛋白和HPV感染与宫颈鳞癌发生发展的关系。方法:采用免疫组化PV-9000方法检测114例宫颈组织标本的p16INK4A表达,用核酸分子快速导流杂交基因芯片技术(HybriMax)检测21种HPV DNA。结果:(1)慢性宫颈炎、CINⅠ、CINⅡ、CINⅢ、SCC组织中p16INK4A蛋白表达阳性率分别为0%、45.83%、72.73%、84.00%、91.30%,随着宫颈病变程度加重,p16INK4A蛋白表达阳性率逐渐增高,表达强度增加,差异有统计学意义(P<0.05)。(2)慢性宫颈炎、CINI、CINⅡ、CINⅢ、SCC中HPV感染阳性率分别为20.00%、37.50%、54.55%、56.00%、73.91%,HPV感染在不同宫颈病变组织中差异有统计学意义(P<0.05)。随宫颈病变程度加重,HPV阳性率呈递增趋势,不同病变组织中位于前3位的HPV感染型别分别为:CINⅠ组,HPV16、18、58;CINⅡ~Ⅲ组,HPV16、33、52;宫颈鳞癌组,HPV16、18,52。(3)相关分析结果显示,病变组织中p16INK4A蛋白表达与HPV感染呈正相关(r=0.268,P<0.05)。结论:p16INK4A蛋白表达与宫颈病变程度有关,p16INK4A可能参与了HPV相关的宫颈癌发生。二者联合检测对宫颈癌筛查和预防具有重要意义。