Telomerase-related advances in hepatocellular carcinoma:A bibliometric and visual analysis

BACKGROUND As a critical early event in hepatocellular carcinogenesis,telomerase activation might be a promising and critical biomarker for hepatocellular carcinoma(HCC)patients,and its function in the genesis and treatment of HCC has gained much attention over the past two decades.AIM To perform a bibliometric analysis to systematically assess the current state of research on HCC-related telomerase.METHODS The Web of Science Core Collection and PubMed were systematically searched to retrieve publications pertaining to HCC/telomerase limited to“articles”and“reviews”published in English.A total of 873 relevant publications related to HCC and telomerase were identified.We employed the Bibliometrix package in R to extract and analyze the fundamental information of the publications,such as the trends in the publications,citation counts,most prolific or influential writers,and most popular journals;to screen for keywords occurring at high frequency;and to draw collaboration and cluster analysis charts on the basis of coauthorship and co-occurrences.VOSviewer was utilized to compile and visualize the bibliometric data.RESULTS A surge of 51 publications on HCC/telomerase research occurred in 2016,the most productive year from 1996 to 2023,accompanied by the peak citation count recorded in 2016.Up to December 2023,35226 citations were made to all publications,an average of 46.6 citations to each paper.The United States received the most citations(n=13531),followed by China(n=7427)and Japan(n=5754).In terms of national cooperation,China presented the highest centrality,its strongest bonds being to the United States and Japan.Among the 20 academic institutions with the most publications,ten came from China and the rest of Asia,though the University of Paris Cité,Public Assistance-Hospitals of Paris,and the National Institute of Health and Medical Research(INSERM)were the most prolific.As for individual contributions,Hisatomi H,Kaneko S,and Ide T were the three most prolific authors.Kaneko S ranked first by H-index,G-index,and overall publication count,while Zucman-Rossi J ranked first in citation count.The five most popular journals were the World Journal of Gastroenterology,Hepatology,Journal of Hepatology,Oncotarget,and Oncogene,while Nature Genetics,Hepatology,and Nature Reviews Disease Primers had the most citations.We extracted 2293 keywords from the publications,120 of which appeared more than ten times.The most frequent were HCC,telomerase and human telomerase reverse transcriptase(hTERT).Keywords such as mutational landscape,TERT promoter mutations,landscape,risk,and prognosis were among the most common issues in this field in the last three years and may be topics for research in the coming years.CONCLUSION Our bibliometric analysis provides a comprehensive overview of HCC/telomerase research and insights into promising upcoming research.

平胃胶囊对恶变后GES-1细胞氧化应激的抑制作用及机制研究

目的:观察平胃胶囊对亚硝酸胺类化合物N-甲基-N’-硝基-N-亚硝基胍(N-methyl-N’-nitro-N-nitrosoguanidine,MNNG)诱导的胃癌前病变(precancerous lesions of gastric cancer,PLGC)细胞模型的影响,并初步探讨其作用机制。方法:制备空白血清和平胃胶囊含药血清备用;MNNG诱导人胃黏膜上皮细胞系GES-1制备PLGC细胞模型,采用倒置显微镜观察细胞形态,免疫荧光法检测增殖细胞相关抗原Ki67的表达水平,进行模型评价。CCK-8法筛选含药血清最佳干预浓度及时间;采用荧光探针DCFH-DA检测细胞内活性氧(reactive oxygen species,ROS)含量;ELISA检测丙二醛(malondialdehyde,MDA)含量;采用相关试剂盒检测超氧化物歧化酶(superoxide dismutase,SOD)和谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性;采用新型荧光探针JC-10检测细胞线粒体膜电位的变化;采用实时荧光定量PCR检测Ki67和黑色素瘤分化相关基因7(melanoma differentiation-associated gene-7,MDA-7)的mRNA表达水平;采用Western blot法测定Ki67、白细胞介素6(interleukin-6,IL-6)和MDA-7的蛋白表达水平。结果:与正常组相比,模型组和空白血清组ROS和MDA含量显著升高(P<0.01),SOD和GSH-Px的活性显著降低(P<0.01),线粒体膜电位显著下降(P<0.01),Ki67和IL-6蛋白表达显著升高(P<0.01),MDA-7蛋白表达显著下降(P<0.01);与空白血清组相比,模型组ROS和MDA含量,SOD和GSH-Px活性,Ki67和MDA-7 mRNA表达水平,Ki67、IL-6和MDA-7蛋白表达水平,以及线粒体膜电位均无显著差异(P>0.05);与空白血清组相比,平胃胶囊含药血清组中ROS和MDA含量显著降低(P<0.01),SOD和GSH-Px活性显著上升(P<0.05),线粒体膜电位显著升高(P<0.01),Ki67和IL-6蛋白表达水平显著下降(P<0.01),MDA-7的mRNA及蛋白表达水平显著升高(P<0.01)。结论:平胃胶囊可显著减轻MNNG诱导的胃黏膜上皮细胞氧化应激损伤和炎症反应,调控促癌基因和抑癌基因的表达,从而发挥防治PLGC的作用。

山橿中生物碱类成分Laetanine、Launobine对乙酸致GES-1细胞损伤的保护作用及机制

目的利用乙酸建立胃黏膜上皮细胞(GES-1细胞)损伤模型,研究山橿中生物碱类成分Laetanine、Launobine对GES-1细胞损伤的保护作用及机制。方法通过MTT细胞增殖/毒性实验确定Laetanine、Launobine的最佳给药浓度。分别以浓度为0.01%~0.2%的乙酸培养液作用于GES-1细胞,作用时间分别为3、4、5h,筛选最佳造模条件。利用乙酸建立GES-1细胞损伤模型,测定Laetanine、Launobine含药培养基处理后的细胞存活率;Griess法测定细胞上清液中NO的浓度;ELISA法测定各组细胞上清液中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)和前列腺素E2(PGE2)水平;WST-1法检测各实验组超氧化物歧化酶(SOD)抑制率,计算SOD活力值。结果0.1%乙酸溶液处理3h为GES-1细胞损伤的最佳造模条件;与模型组比较,Laetanine、Launobine给药组均能显著升高GES-1细胞存活率(P<0.01);经Laetanine、Launobine处理后,细胞上清液中的NO、TNF-α、IL-6和PGE2水平显著降低,SOD活力显著升高(P<0.01或P<0.05)。结论山橿中生物碱类成分Laetanine和Launobine均能保护乙酸损伤的GES-1细胞,减轻GES-1细胞的受损程度,其作用机制可能与其降低NO、TNF-α、IL-6和PGE2水平,升高SOD水平有关,表明Laetanine和Launobine可能为山橿发挥抗胃溃疡作用的有效成分。

基于gE蛋白的羊伪狂犬病病毒间接ELISA的建立与应用

为建立羊源伪狂犬病病毒(Pseudorabies virus,PRV)抗体的检测方法,从PRV中对gE基因进行克隆,并构建重组载体对gE蛋白进行原核表达,以重组gE蛋白为包被抗原,建立PRV抗体间接ELISA检测方法,并进行临床样本检测。结果显示,重组gE蛋白大小为42 ku,以包涵体形式表达;Western blot检测表明重组蛋白具有良好的反应原性;重组蛋白作为包被抗原的最佳工作浓度为1μg/mL,待检血清100倍稀释,以HRP标记的兔抗山羊IgG 10000倍稀释作为二抗;检测临床样本时判定阴阳性的临界值为0.284;灵敏性试验结果显示,羊PRV阳性血清稀释2048倍时检测结果仍为阳性;批内变异系数(2.45%~5.00%)与批间变异系数(2.55%~7.41%)均小于10%;采用建立的方法检测其他常见羊源病毒阳性血清结果均为阴性;对收集的376份临床羊血清进行检测,PRV阳性率为10.6%。建立的间接ELISA检测方法可用于羊源样本中伪狂犬病病毒抗体的检测,该方法的建立为羊场PRV抗体检测提供了技术支持。

Effect of VEGF,P53 and telomerase on angiogenesis of gastric carcinoma tissue

Objective:To investigate the effect of vascular endothelial growth factor(VEGF),P53 and telomerase on angiogenesis in gastric carcinoma tissue.Methods:A total of 95 surgical resection samples of gastric cancer tissue after pathological diagnosis are collected to observe the VEGF,P53 and telomerase expression using immunohistochemical methods.Relationship between their expression and its influence on angiogenesis in gastric carcinoma tissue were analyzed.Results:Microvascular density(MVD)and the expression of VEGF,P53 and telomerase were positively correlated.Expression of VEGF and P53 protein were related to tumor type and lymph metastasis,and also a correlation was observed between P53 and VEGF.The telomerase expression had no correlation with VEGF,and P53.Conclusions:VEGF angiogenesis has a angiogenesis promoting effect on gastric cancer tissue development and plays an important role in tumor generation and metastasis.Mutant P53 promotes the tumor angiogenesis generation by adjusting VEGF.Telomerase has a certain role in promoting activity of angiogenesis through different way rather than P53.

Testicular expression of survivin and human telomerase reverse transcriptase(hTERT)associated with spermatogenic function in infertile patients

Aim： To characterize the coexpression of survivin, an inhibitor of apoptosis （IAF）, and human telomerase reverse transcriptase （hTERT） in human testes with varying spermatogenic function. Methods： Transcript levels of survivin mRNA and hTERT mRNA were determined in normal testes （n = 11） and testes with defective spermatogenesis （n = 28） using real-time reverse-transcription polymerase chain reaction （RT-PCR）. The histological work-up was performed according to a modified Johnsen score. Results： Expressions of both survivin and hTERT were highest at median levels of 96.8 and 709 in normal spermatogenesis and dropped to 53.3 and 534 in testes with postmeiotic spermatogenic arrest （n = 10）. In severe spermatogenic failure （n = 18）, survivin expression was lacking in most specimens （n = 16）, whereas at least low levels of testicular hTERT expression were largely detectable with a normalized expression of 73 in premeiotic spermatogenic arrest （n = 7） and 45 in patients with Sertoli cell-only syndrome （SCOS） （n = 3）. Both survivin and hTERT expressions increased with a progressing Johnsen score （P for trend = 0.001）. Conclusion： Although both survivin and hTERT are correlated with spermatogenic function, they show different expression patterns in testes of infertile patients. These findings substantiate results from studies in the rodent testis suggesting a predominant expression of survivin in meiotically dividing germ cells. （Asian J Andro12006 Jan; 8： 95-100）

Telomere,telomerase and digestive cancer

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Common telomerase reverse transcriptase promoter mutations in hepatocellular carcinomas from different geographical locations

AIM: To determine the mutation status of human telomerase reverse transcriptase gene(TERT) promoter region in hepatocellular carcinoma(HCC) from different geographical regions.METHODS: We analyzed the genomic DNA sequences of 59 HCC samples comprising 15 cell lines and 44 primary tumors,collected from patients living in Asia,Europe and Africa.We amplified a 474 bp DNA fragment of the promoter region of TERT gene including the 1295228 and 1295250 sequence of chromosome 5 by using PCR.Amplicons were then sequenced by Sanger technique and the sequence data were analyzed with by using DNADynamo software in comparison with wild type TERT gene sequence as a reference.RESULTS: The TERT mutations were found highly frequent in HCC.Eight of the fifteen tested cell lines displayed C228 T mutation,and one had C250 T mutation with a mutation frequency up to 60%.All of the mutations were heterozygous and mutually exclusive.Ten out of forty-four tumors displayed C228 T mutation,and additional five tumors had C250 T mutation providing evidence for mutation frequency of 34% in primary tumors.Considering the geographic origins of HCC tumors tested,TERT promoter mutation frequencies were higher in African(53%),when compared to non-African(24%) tumors(P = 0.056).There was also a weak inverse correlation between TERT promoter mutations and murine double minute 2 single nucleotide polymorphism 309 TG polymorphism(P = 0.058).Mutation frequency was nearly two times higher in established HCC celllines(60%) compared to the primary tumors(34%).CONCLUSION: TERT promoter is one of most frequent mutational targets in liver cancer,and hepatocellular carcinogenesis is highly associated with the loss of telomere-dependent cellular senescence control.

七星关区耕地土壤Ge地球化学特征及其与作物的吸收关系

掌握耕地土壤Ge含量特征及其与作物的吸收关系,对耕地Ge的开发利用及科学选种具有重要意义。为此,以贵州省七星关区土地质量地球化学调查评价项目数据为基础,统计Ge的地球化学参数,分析该区土壤Ge地球化学特征和作物对Ge的吸收规律。结果显示:七星关区耕地土壤Ge含量在(0.86~2.48)×10^(-6),平均值1.74×10^(-6),与全国土壤Ge背景值相当。通过地统计分析,圈定富Ge耕地面积65853.54 hm^(2),占全区耕地总面积的47.41%,主要分布于研究区西北和西南部。农作物对土壤Ge的生物吸收系数(Ax)均小于1%,均处于极弱摄取水平。采用相关分析等方法讨论耕地土壤富Ge成因及影响作物吸收Ge的环境因子,得出以下结论:①土壤Ge含量主要受成土母质控制,同时受到风化成土过程的影响,并在七星关区耕地有机质含量丰富和偏酸性的土壤背景下,造成土壤Ge富集;②酸性土壤中,作物对土壤Ge的生物吸收系数(Ax)与pH呈弱负相关关系,而在中—碱性土壤中,作物对土壤Ge的生物吸收系数(Ax)与pH呈正相关关系,即偏酸性土壤是导致作物对Ge生物吸收能力低的原因。

Transplantation of human telomerase reverse transcriptase gene-transfected Schwann cells for repairing spinal cord injury

Transfection of the human telomerase reverse transcriptase（h TERT）gene has been shown to increase cell proliferation and enhance tissue repair.In the present study,h TERT was transfected into rat Schwann cells.A rat model of acute spinal cord injury was established by the modified free-falling method.Retrovirus PLXSN was injected at the site of spinal cord injury as a vector to mediate h TERT gene-transfected Schwann cells（1×10^（10）/L;10μL）or Schwann cells（1×10^（10）/L;10μL）without h TERT gene transfection.Between 1 and 4 weeks after model establishment,motor function of the lower limb improved in the h TERT-transfected group compared with the group with non-transfected Schwann cells.Terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling and reverse transcription-polymerase chain reaction results revealed that the number of apoptotic cells,and gene expression of aquaporin 4/9 and matrix metalloproteinase 9/2decreased at the site of injury in both groups;however,the effect improved in the h TERT-transfected group compared with the Schwann cells without h TERT transfection group.Hematoxylin and eosin staining,PKH26 fluorescent labeling,and electrophysiological testing demonstrated that compared with the non-transfected group,spinal cord cavity and motor and sensory evoked potential latencies were reduced,while the number of PKH26-positive cells and the motor and sensory evoked potential amplitude increased at the site of injury in the h TERT-transfected group.These findings suggest that transplantation of h TERT gene-transfected Schwann cells repairs the structure and function of the injured spinal cord.

Expression of Mouse Telomerase Catalytic Subunit mTERT Gene in Testis of SD Rats and Its Significance

To study the expression of mTERT gene in the testis of SD rats and its significance, in situ hybridization (ISH) techniques were used to detect the expression of telomerase gene mTERT mRNA in the testis of SD rats The expression of mTERT was detectable in different-age male SD rats' testis There was a positive correlation between the expression of mTERT and the location of germ cells (spermatogonia, spermatocyte, spermatid) In Sertoli cells, leydig cell and spermatozoa, telomerase mTERT was not detected Type A spermatogonia expressed the highest level of telomerase mTERT mRNA Our results suggest that the expression of mTERT gene in the testis of SD rats is of lifetime and coincide with the telomerase activity

Detection of Telomerase Activity and the Expression of Telomerase Subunits in the Patients with Acute Myelogenous Leukaemia

Telomerase activity and the expression of telomerase subunits (for example, telomerase reverse transcriptase and telomerase associated protein 1 and telomerase RNA component) of peripheral white blood cells were detected in the patients with acute myelogenous leukaemia (AML) and the correlation between telomerase activity and the expression of telomerase subunits was observed. In 94 peripheral white blood cells from 18 healthy volunteers and 76 patients with AML, including 31 AML at initial presentation, 24 at relapse and 21 at complete remission, the telomerase activity and telomerase subunits mRNA or RNA were detected by PCR ELISA and RT PCR respectively. The results showed that the positive rate of telomerase from patients with AML at initial presentation, at relapse and at complete remission was 74.1 %, 79.2 % and 4.8 % respectively. The positive rate of telomerase reverse transcriptase mRNA from healthy volunteers, AML at initial presentation, AML at relapse and AML at complete remission was 5.6 %, 80.6 %, 83.3 % and 9.5 % respectively. The positive rate of telomerase associated protein 1 mRNA and telomerase RNA component in all samples were 100 %. It was suggested that the up regulation of telomerase activity and the expression of telomerase reverse transcriptase is correlated closely with the occurrence and relapse of AML, so telomerase activity and the expression of telomerase reverse transcriptase may be used to estimate the curative effect and predict relapse of AML. Moreover, the up regulation of telomerase activity is correlated with the expression of telomerase reverse transcriptase significantly.

TELOMERASE ACTIVITY DURING 7,12-DIMETHYLBENZ [a] ANTHRACENE-INDUCED HAMSTER BUCCAL POUCH CARCINOGENESIS

Objective: To investigate the roles of telomerase activity (TA) in relation to hamster buccal pouch tumor progression. Methods: male hamster were treated three times weekly with 0.5% of 7, 12-dimethyl-benzanthracene (DMBA) over a IS weeks experimental period. Hamsters were sacrificed at 3, 6, 9, 12 and 15 weeks after treatment. Telomerase activity of hamster buccal pouch tissue were measured along with the analyses of the formation of DMBA-induced hamster buccal pouch tumors. Results: DMBA-induced squamous cell carcinomas were found at the 6th week after dosing. Telomerase activity elevation began at the 3rd week and was increasing to a plateau at the 12th week. Conclusion: Our results show that telomerase activity in the target tissue may be detected at the early stage of the DMBA-induced hamster buccal pouch tumor formation and suggests that telomerase activity may be used as a biomarker for an early clinical detection of buccal pouch cancer.

TELOMERASE: A NOVEL TARGET OF ANTITUMOR AGENTS

Telomerase activity was found to be high in various human cancers, but absent in most normal tissues. Its expression pattern made it a novel target for antitumor agents. Several strategies against telomerase were presented in this review. Targeting the telomerase RNA component by oligonucleotide/ribozyme was considered to be one of the most hopeful approaches. Some progresses were made in this area, such as the use of PANs and 2–5A antisense compounds. The relationships among telomerase activity and cell differentiation, signal transduction, oncogene, tumor suppressor gene as well as cell cycle modulation also provided a series of valuable ideas in designing anti-telomerase drugs for cancer therapy. In conclusion, although there is still a long way in understanding the mechanism and regulation of telomerase, the advance of studies on telomerase has allowed the development of numerous strategies for the treatment of cancer.

MicroRNA-mediated NBS1 Gene Silence and Its Effects on Telomerase Activation in Hela Cells

Objective： To research the silence of NBS1 after transfection microRNA expressing eukaryotic recombinants and the changes of telomerase activation in telomerase-positive cell line Hela. Methods： According to the sequence of NBS1 mRNA, the NBS1 pre-microRNA was designed and synthesized, then cloned into the GFP reporter pcDNA6.2-GW/EmGFP-miR vector and transfected into Hela cells. The integrity of the insert fragment was verified through colony PCR and sequencing analysis. The NBS1 gene expression of NBS1 microRNA recombinants was detected by Real-Time PCR and western blot. Telomerase activity in Hela cells was assayed by TRAP-PCR-EB. Results： Sequences of insert fragment in microRNA expressing recombinants were correct. The NBS1 gene expression was decreased, and the telomerase activation of Hela cell reduced. Conclusion： NBS1 microRNA inhibits NBS1 gene expression, and depresses telomerase activation of Hela cells. This confirms that there is relevance between NBS 1 gene and telomerase activity.

Combination of telomerase antisense oligonucleotides simultaneously targeting hTR and hTERT produces synergism of inhibition of telomerase activity and growth in human colon cancer cell line

AIM: To investigate synergism of inhibition of telomerase activity and proliferation of human colon cancer cells by combination of telomerase antisense oligonucleotides (ASODNs) simultaneously targeting human telomerase RNA (hTR) and human telomerase reverse transcriptase (hTERT)in vitro.METHODS: ASODN of hTR and ASODN of hTERT were transfected into human colon cancer SW480 cells by liposomal transfection reagents. Telomerase activity of SW480 cells was examined using telomeric repeat amplification protocol (TRAP)-enzyme-linked immunosorbent assay (PCR-ELISA). Proliferation activity of SW480 cells was tested by methyl thiazolyl tetrazolium assay. Apoptosis and cell cycle were analyzed by flow cytometry.RESULTS: The telomerase activity and cell survival rate in SW480 cells transfected with 0.2 μmol/L of ASODN of hTR or ASODN of hTERT for 24-72 h were significantly decreased in a time-dependent manner compared with those after treatment with sense oligonucleotides and untreated (telomerase activity: 24 h, 73%, 74% vs 99%,98%; 48 h, 61%, 55% vs 98%, 99%; 72 h, 41%, 37% vs 99%, 97%; P＜0.01; cell survival rate: 24 h, 88%, 86%vs94%, 98%; 48 h, 49%, 47% vs94%, 97%; 72 h, 44%,42% vs 92%, 96%; P＜0.01). Moreover, the telomerase activity and the cell survival rate in SW480 cells treated by the combination of telomerase anti-hTR and anti-hTERT were more significantly suppressed than single anti-hTR or anti-hTERT (telomerase activity: 24 h, 59% vs 73%,74%; 48 h, 43% vs61%, 55%; 72 h, 18% vs41%, 37%;P＜0.01; cell survival rate: 24 h, 64% vs88%, 86%; 48 h,37% vs49%, 47%; 72 h, 25% vs44%, 42%; P＜0.01).Meanwhile, the apoptosis rates in the combination group were markedly increased compared with those in the single group (24 h, 18.0% vs 7.2%, 7.4%; 48 h, 23.0%vs 13.0%, 14.0%; 72 h, 28.6% vs13.2%, 13.75; P＜0.01).Cells in combination group were arrested at G0/G1 phase.CONCLUSION: Telomerase anti-hRT and anti-hTERT suppress telomerase activity, and inhibit growth of human colon cancer cells probably via induction of apoptosis and retardation of cell cycle. Additionally, combined use of telomerase ASODNs targeting both hTR and hTERT yields synergistic action selective for human colon cancer.

The Effect of Nano-apatite on the Expression of Telomerase Gene of Human Hepatocellular Carcinoma Cells

To investigate the effect of nano-apatite on the expression of the telomerase gene of human hepatocellular carcinoma cell lines and further explore the mechanism of the nano-apatite inhibiting cancer cells. Using the hybridization in situ method to detect the expression of the telomerase gene of human hepatocellular carcinoma cells treated with the nano-apatite for 4 h at 37 ℃ . The hybridization in situ showed that the cytoplasm of the positive cells was stained in nigger- brown. The positive cell rate of the control group was 88.49% , the cisplatin group was 25.6% , the nano-apatite group was 63.6% . The activity of telomerase gene was both obviously dedined comparing with the control group and the difference had significance （ p 〈 0. 05, p 〈 0.01 ）. The nanoapatite obviously inhabit the expression of the telomerase gene of human hepatocellular carcinoma cells.

Immortalization of human umbilical vein endothelial cells with telomerase reverse transcriptase and simian virus 40 large T antigen

Objective: To establish normally conditionally-immortalized human umbilical vein endothelial cells (HUVECs) by ectopic expression of the human telomerase catalytic enzyme (hTERT) and simian virus 40 large T (SV40 LT) antigen. Methods:Primary HUVECs were transfected with recombinant retrovirus containing hTERT or SV40 LT respectively. Subsequently drug resistant cell clones were screened and expanded for further studies. Endothelial cell biomarkers were confirmed by examination.Results: The morphological phenotype of the transfected cells was similar to the non-transfected cells. Von Willebrand factor,hTERT and SV40 LT could be detected in transfected HUVECs. Moreover, higher telomerase activity in transfected cells was maintained for over 50 population doublings compared with only low level of endogenous telomerase transiently at early population doublings in primary HUVECs. When exposed to TNF-α (tumor necrosis factor-α), the expression of E-selectin in transfected cells was significantly up-regulated, but no alteration of endothelial lipase was found. Conclusion: Ectopic coexpression of hTERT and SV40 LT can effectively immortalize HUVECs without tumorigenicity in vitro. Immortalized HUVECs may be an ideal target of further molecular function studies.

Study of the expressions of p53 and bcl-2 genes, the telomerase activity and apoptosis in GIST patients

AIM: To explore the relationship between clinicobiological behavior and the expression levels of telomerase activity, apoptosis, p53 gene and bcl-2 gene in gastrointestinal stromal tumors (GISTs). METHODS: The intensity of telomerase activity, apoptosis, p 53 and bcl -2 expression in GISTs were detected by telomeric repeat amplification protocol, in situ end-labeling technique, and immunohistochemistry, respectively. RESULTS: The positive rates of telomerase activity of malignant GIST, potential malignant GIST and benign GIST were 85% (17/20), 22.8% (2/9) and 0 (0/9), respectively. The apoptosis indices of malignant GIST, potential malignant GIST, and benign GIST were 11.7 ± 5.4, 30.2 ± 5.6 and 45.2 ± 7.2, respectively. The intensity of telomerase activity and apoptosis were related to the biological characteristics of GISTs (85% vs 22.8%, 0, 0; P < 0.01 or 11.7 ± 5.4 vs 30.2 ± 5.6, 45.2 ± 7.2, 72.1 ± 9.3; P < 0.05). The intensity of telomerase activity was negatively correlated with cellular apoptosis (22.9 ± 8.4 vs 9.5 ± 5.7, P < 0.01). The intensity of telomerase activity was positively correlated with p53, bcl-2 expression (40.0% vs 78.9%, 40.0% vs 84.2%; P < 0.05). CONCLUSION: The detection of telomerase activity, apoptosis and its control genes in GIST will be helpful for the discrimination of the malignant and benign GIST and evaluation of the prognosis.

Value of endoscopic methylene blue and Lugol's iodine double staining and detection of GST-n and telomerase in the early diagnosis of esophageal carcinoma

AIM: To explore the expressions of GST-n and telomerase activity in esophageal carcinoma and premalignant lesions and to investigate the value of endoscopic methylene blue(MB) and Lugol's iodine double staining.METHODS: Seventy-two patients with esophagopathy were sprayed endoscopically with MB and Lugol's iodine in proper order and the areas stained blue and brown,and the area between the blue and brown stains were obtained. Depending on the pattern of mucosal staining,biopsy specimen was obtained. GST-n and telomerase activity in specimens were examined by immunohistochemistry and PCR-based silver staining telomeric repeat amplification protocol, respectively.RESULTS: After MB and Lugol's iodine staining, the area between both the colors was obtained in 64 of the 72patients and the areas were stained blue and brown in all of the 72 patients. Association test of two simultaneous ordinal categorical data showed a correlation between the esophageal mucosal staining and the esophageal histology(P＜0.005). The expression of GST-n and telomerase activity in esophageal carcinoma and premalignant lesions increased. The expression of GST-n and telomerase activity in dysplasia and carcinoma was significantly higher than that in normal epithelium (P＜0.005). The expression in hyperplasia was slightly higher than that in normal epithelium.With the lesions progressing from low- to moderate- to high-grade dysplasia, the positive rate increased (P＜0.025).Expression of GST-n was correlated with that of telomerase activity in dysplasia and carcinoma ((ψ) = 0.4831, P＜0.005;(ψ) = 0.3031, P＜0.025, respectively); but there was no correlation between them in normal epithelium and hyperplasia.CONCLUSION: The expression of GST-n and telomerase may be an early event in the carcinogenesis of esophagus.They may play an induced and synergistic role with each other in the carcinogenesis of esophagus. Endoscopic MB and Lugol's iodine double staining and detection of GST-n and telomerase activity may contribute to the early diagnosis of esophageal carcinoma.