1.Research advances in telomere-telomerase in neurodegenerative diseases
Journal of Apoplexy and Nervous Diseases 2024;41(2):169-174
Previous studies mainly used β-amyloid and α-synuclein as the biomarkers for the diagnosis of neurodegenerative diseases. In recent years,studies have shown that telomeres at the end of chromosome can be used as an index to measure the degree of biological aging,and telomere length and telomerase activity may also be used as the blood markers to evaluate the risk,progression,and poor prognosis of neurodegenerative diseases in the elderly;however,there is still a lack of consistency between the research findings in China and globally. Understanding the role of telomere-related biomarkers in age-related diseases can help clinicians learn more about the mechanism of disease development and progression. This article reviews the latest research advances in the telomere-telomerase system in neurodegenerative diseases,in order to introduce the influence of telomere length and telomerase activity on neurodegenerative diseases and their potential mechanisms of action.
Telomere
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Telomerase
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Neurodegenerative Diseases
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Alzheimer Disease
;
Parkinson Disease
2.Lamin B1 regulates the growth of hepatocellular carcinoma cells by influencing telomerase activity.
Ruiguan WANG ; Si CHEN ; Zhijia SUN ; Shikun WANG ; Jie WANG ; Lingmei QIN ; Jiangbo LI
Chinese Journal of Biotechnology 2023;39(4):1609-1620
Lamin B1 (LMNB1) is highly expressed in liver cancer tissues, and its influence and mechanism on the proliferation of hepatocellular carcinoma cells were explored by knocking down the expression of the protein. In liver cancer cells, siRNAs were used to knock down LMNB1. Knockdown effects were detected by Western blotting. Changes in telomerase activity were detected by telomeric repeat amplification protocol assay (TRAP) experiments. Telomere length changes were detected by quantitative real-time polymerase chain reaction (qPCR). CCK8, cloning formation, transwell and wound healing were performed to detect changes in its growth, invasion and migration capabilities. The lentiviral system was used to construct HepG2 cells that steadily knocked down LMNB1. Then the changes of telomere length and telomerase activity were detected, and the cell aging status was detected by SA-β-gal senescence staining. The effects of tumorigenesis were detected by nude mouse subcutaneous tumorigenesis experiments, subsequent histification staining of tumors, SA-β-gal senescence staining, fluorescence <i>in situi> hybridization (FISH) for telomere analysis and other experiments. Finally, the method of biogenesis analysis was used to find the expression of LMNB1 in clinical liver cancer tissues, and its relationship with clinical stages and patient survival. Knockdown of LMNB1 in HepG2 and Hep3B cells significantly reduced telomerase activity, cell proliferation, migration and invasion abilities. Experiments in cells and tumor formation in nude mice had demonstrated that stable knockdown of LMNB1 reduced telomerase activity, shortened telomere length, senesced cells, reduced cell tumorigenicity and KI-67 expression. Bioinformatics analysis showed that LMNB1 was highly expressed in liver cancer tissues and correlated with tumor stage and patient survival. In conclusion, LMNB1 is overexpressed in liver cancer cells, and it is expected to become an indicator for evaluating the clinical prognosis of liver cancer patients and a target for precise treatment.
Animals
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Mice
;
Telomerase/metabolism*
;
Carcinoma, Hepatocellular/genetics*
;
Liver Neoplasms/genetics*
;
Telomere Shortening
;
In Situ Hybridization, Fluorescence
;
Mice, Nude
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Telomere/pathology*
;
Carcinogenesis
3.Genetic Subtypes and Pretreatment Drug Resistance in the Newly Reported Human Immunodeficiency Virus-Infected Men Aged≥50 Years Old in Guangxi.
Ning-Ye FANG ; Wen-Cui WEI ; Jian-Jun LI ; Ping CEN ; Xian-Xiang FENG ; Dong YANG ; Kai-Ling TANG ; Shu-Jia LIANG ; Yu-Lan SHAO ; Hua-Xiang LU ; He JIANG ; Qin MENG ; Shuai-Feng LIU ; Qiu-Ying ZHU ; Huan-Huan CHEN ; Guang-Hua LAN ; Shi-Xiong YANG ; Li-Fang ZHOU ; Jing-Lin MO ; Xian-Min GE
Acta Academiae Medicinae Sinicae 2023;45(3):399-404
Objective To analyze the genetic subtypes of human immunodeficiency virus (HIV) and the prevalence of pretreatment drug resistance in the newly reported HIV-infected men in Guangxi. Methods The stratified random sampling method was employed to select the newly reported HIV-infected men aged≥50 years old in 14 cities of Guangxi from January to June in 2020.The pol gene of HIV-1 was amplified by nested reverse transcription polymerase chain reaction and then sequenced.The mutation sites associated with drug resistance and the degree of drug resistance were then analyzed. Results A total of 615 HIV-infected men were included in the study.The genetic subtypes of CRF01_AE,CRF07_BC,and CRF08_BC accounted for 57.4% (353/615),17.1% (105/615),and 22.4% (138/615),respectively.The mutations associated with the resistance to nucleoside reverse transcriptase inhibitors (NRTI),non-nucleoside reverse transcriptase inhibitors (NNRTI),and protease inhibitors occurred in 8 (1.3%),18 (2.9%),and 0 patients,respectively.M184V (0.7%) and K103N (1.8%) were the mutations with the highest occurrence rates for the resistance to NRTIs and NNRTIs,respectively.Twenty-two (3.6%) patients were resistant to at least one type of inhibitors.Specifically,4 (0.7%),14 (2.3%),4 (0.7%),and 0 patients were resistant to NRTIs,NNRTIs,both NRTIs and NNRTIs,and protease inhibitors,respectively.The pretreatment resistance to NNRTIs had much higher frequency than that to NRTIs (2.9% <i>vs.i>1.3%;<i>χ2i>=3.929,<i>Pi>=0.047).The prevalence of pretreatment resistance to lamivudine,zidovudine,tenofovir,abacavir,rilpivirine,efavirenz,nevirapine,and lopinavir/ritonavir was 0.8%, 0.3%, 0.7%, 1.0%, 1.3%, 2.8%, 2.9%, and 0, respectively. Conclusions CRF01_AE,CRF07_BC,and CRF08_BC are the three major strains of HIV-infected men≥50 years old newly reported in Guangxi,2020,and the pretreatment drug resistance demonstrates low prevalence.
Male
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Humans
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Middle Aged
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Reverse Transcriptase Inhibitors/therapeutic use*
;
HIV Infections/drug therapy*
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Drug Resistance, Viral/genetics*
;
China/epidemiology*
;
Mutation
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HIV-1/genetics*
;
Protease Inhibitors/therapeutic use*
;
Genotype
4.Pathological features and clinicopathological significance of TERT promoter mutation in breast fibroepithelial tumors without definite diagnosis.
Ji Gang WANG ; Yan Jiao HU ; Jing Jing GUAN ; Hong Yun LIU ; Zhong Jun BI ; Long Xiao ZHANG ; Yi Xuan LIU ; Xiao Ming XING
Chinese Journal of Pathology 2023;52(2):153-159
Objective: To investigate the pathological features and the clinicopathological significance of TERT detection in those tumors that were difficult to diagnosis. Methods: A total of 93 cases of fibroepithelial tumors without definite diagnosis were collected from the Affiliated Hospital of Qigndao University between 2013 and 2021. The clinical details such as patients' age and tumor size were collected. All slides were re-reviewed and the pathologic parameters, including stromal cellularity, stromal cell atypia, stromal cell mitoses, and stromal overgrowth were re-interpreted. Sanger sequencing was used to detect TERT promoter status, and immunohistochemistry was performed to detect TERT protein expression. The relationship between TERT promoter mutation as well as protein expression levels and the clinicopathological parameters were also analyzed. Results: The patients' ages ranged from 30 to 71 years (mean of 46 years); the tumor size ranged from 1.2 to 8.0 cm (mean 3.8 cm). These tumors showed the following morphologic features: leafy structures in the background of fibroadenoma, or moderately to severely abundant stromal cells. The interpretations of tumor border status were ambiguous in some cases. The incidence of TERT promoter mutation was high in patients of age≥50 years, tumor size≥4 cm, and stromal overgrowth at ×4 or ×10 objective, and these clinicopathologic features were in favor of diagnosis of phyllodes tumors. TERT protein expression levels was not associated with the above clinicopathologic parameters and its promoter mutation status. Conclusions: The diagnostic difficulty for the breast fibroepithelial tumors is due to the difficulty in recognition of the leafy structures or in those cases with abundant stromal cells. A comprehensive evaluation combined with morphologic characteristics and molecular parameters such as TERT promoter may be helpful for the correct diagnosis and better evaluating recurrence risk.
Humans
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Adult
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Middle Aged
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Aged
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Female
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Neoplasms, Fibroepithelial/pathology*
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Phyllodes Tumor/genetics*
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Stromal Cells
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Fibroadenoma/pathology*
;
Breast Neoplasms/pathology*
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Mutation
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Telomerase/genetics*
5.HIV-1 Subtype Diversity and Factors Affecting Drug Resistance among Patients with Virologic Failure in Antiretroviral Therapy in Hainan Province, China, 2014-2020.
De E YU ; Yu Jun XU ; Mu LI ; Yuan YANG ; Hua Yue LIANG ; Shan Mei ZHONG ; Cai QIN ; Ya Nan LAN ; Da Wei LI ; Ji Peng YU ; Yuan PANG ; Xue Qiu QIN ; Hao LIANG ; Kao Kao ZHU ; Li YE ; Bing Yu LIANG
Biomedical and Environmental Sciences 2023;36(9):800-813
OBJECTIVE:
This study aimed to determine the HIV-1 subtype distribution and HIV drug resistance (HIVDR) in patients with ART failure from 2014 to 2020 in Hainan, China.
METHODS:
A 7-year cross-sectional study was conducted among HIV/AIDS patients with ART failure in Hainan. We used online subtyping tools and the maximum likelihood phylogenetic tree to confirm the HIV subtypes with <i>poli> sequences. Drug resistance mutations (DRMs) were analyzed using the Stanford University HIV Drug Resistance Database.
RESULTS:
A total of 307 HIV-infected patients with ART failure were included, and 241 available <i>poli> sequences were obtained. Among 241 patients, CRF01_AE accounted for 68.88%, followed by CRF07_BC (17.00%) and eight other subtypes (14.12%). The overall prevalence of HIVDR was 61.41%, and the HIVDR against non-nucleoside reverse transcriptase inhibitors (NNRTIs), nucleotide reverse transcriptase inhibitors (NRTIs), and protease inhibitors (PIs) were 59.75%, 45.64%, and 2.49%, respectively. Unemployed patients, hypoimmunity or opportunistic infections in individuals, and samples from 2017 to 2020 increased the odd ratios of HIVDR. Also, HIVDR was less likely to affect female patients. The common DRMs to NNRTIs were K103N (21.99%) and Y181C (20.33%), and M184V (28.21%) and K65R (19.09%) were the main DRMs against NRTIs.
CONCLUSION
The present study highlights the HIV-1 subtype diversity in Hainan and the importance of HIVDR surveillance over a long period.
Humans
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Reverse Transcriptase Inhibitors/therapeutic use*
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HIV-1/genetics*
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Cross-Sectional Studies
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Phylogeny
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Anti-HIV Agents/therapeutic use*
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Drug Resistance, Viral/genetics*
;
HIV Infections/epidemiology*
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Mutation
;
China/epidemiology*
;
Prevalence
;
Genotype
6.Significance of TERT promoter mutation in differential diagnosis of non-invasive inverted urothelial lesions of bladder.
Y H ZHANG ; J J XIE ; J G WANG ; Y WANG ; X H ZHAN ; J GAO ; H Y HE
Chinese Journal of Pathology 2023;52(12):1216-1222
Objective: To investigate the gene mutation of telomerase reverse transcriptase (TERT) promoter in inverted urothelial lesions of the bladder and its significance in differential diagnosis. Methods: From March 2016 to February 2022, a total of 32 patients with inverted urothelial lesions diagnosed in Department of Pathology at Qingdao Chengyang People's Hospital and 24 patients at the Affiliated Hospital of Qingdao University were collected, including 7 cases of florid glandular cystitis, 13 cases of inverted urothelial papilloma, 8 cases of inverted urothelial neoplasm with low malignant potential, 17 cases of low-grade non-invasive inverted urothelial carcinoma, 5 cases of high-grade non-invasive inverted urothelial carcinoma, and 6 cases of nested subtype of urothelial carcinoma were retrospectively analyzed for their clinical data and histopathological features. TERT promoter mutations were analyzed by Sanger sequencing in all the cases. Results: No mutations in the TERT promoter were found in the florid glandular cystitis and inverted urothelial papilloma. The mutation rates of the TERT promoter in inverted urothelial neoplasm with low malignant potential, low grade non-invasive inverter urothelial carcinoma, high grade non-invasive inverted urothelial carcinoma and nested subtype urothelial carcinoma were 1/8, 8/17, 2/5 and 6/6, respectively. There was no significant difference in the mutation rate of TERT promoter among inverted urothelial neoplasm with low malignant potential, low-grade non-invasive inverted urothelial carcinoma, and high-grade non-invasive inverted urothelial carcinoma (<i>Pi>>0.05). All 6 cases of nested subtype of urothelial carcinoma were found to harbor the mutation, which was significantly different from inverted urothelial neoplasm with low malignant potential and non-invasive inverted urothelial carcinoma (<i>Pi><0.05). In terms of mutation pattern, 13/17 of TERT promoter mutations were C228T, 4/17 were C250T. Conclusions: The morphology combined with TERT promoter mutation detection is helpful for the differential diagnosis of bladder non-invasive inverted urothelial lesions.
Humans
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Urinary Bladder Neoplasms/genetics*
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Carcinoma, Transitional Cell/pathology*
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Urinary Bladder/pathology*
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Diagnosis, Differential
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Retrospective Studies
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Mutation
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Cystitis/genetics*
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Neoplasms, Glandular and Epithelial/diagnosis*
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Papilloma/diagnosis*
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Telomerase/genetics*
7.Role of brain and muscle ARNT-like protein 1 in the rat periodontitis-induced liver injury model.
Xiao Meng LIU ; Niu Ben CAO ; Yu DENG ; Yu Bo HOU ; Xin Chan LIU ; Hao Nan MA ; Wei Xian YU
Chinese Journal of Stomatology 2022;57(10):1048-1056
Objective: Brain and muscle ARNT-like protein 1 (BMAL1) is a core component of hepatocyte molecular clock and plays an important role in the regulation of other related rhythmic genes in the body through a transcriptional-translational feedback loop in molecular circadian oscillations. Therefore, the aim of this study was to investigate the role of BMAL1 in the rat periodontitis-induced liver injury. Methods: Twelve male Wistar rats were divided into the control group and the periodontitis group according to the random number table method. The rats in the control group were untreated. The periodontitis models were established by ligating the necks of the bilateral maxillary first molars in the periodontitis group rats. After 8 weeks, periodontal clinical indexes of rats in both groups were examined and executed. Micro-CT scans of the maxilla were performed and levels of the alveolar bone resorption were analyzed. Pathological changes in periodontal and liver tissue of rats in two groups were detected by HE and oil red O staining. Biochemical kits were used to detect glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), total cholesterol (TC) and triglycerides (TG) in serum. The gene and protein expression levels of BMAL1, nuclear factor kappa-B (NF-κB) and tumor necrosis factor-α (TNF-α) in liver tissue were measured by real time fluorescent quantitative-PCR (qRT-PCR), immunohistochemistry (IHC) and Western blotting (WB) assays. Apoptosis was detected in liver tissues by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) kit staining. Results: The results of HE staining of maxillary first molars and micro-CT results of maxillary bones showed that alveolar bone resorption was significant in the periodontitis group of rats. The liver histopathology results showed infiltrated inflammatory cells in the liver tissue, disorganized liver cords and a large number of lipid droplets formed in the hepatocytes of the periodontitis group compared with the control group. The results of serum biochemical assay showed that the levels of GOT [(62.77±2.59) U/L], GPT [(47.54±1.04) U/L], TC [(3.19±0.23) mmol/L] and TG [(1.11±0.09) mmol/L] in the serum of rats with periodontitis were significantly higher than that in the control group respectively [GOT: (38.66±2.47) U/L, GPT: (31.48±1.57) U/L, TC: (1.60±0.05) mmol/L and TG: (0.61±0.09) mmol/L](<i>P=i>0.003, <i>P=i>0.001, <i>P=i>0.002, <i>P=i>0.038). qRT-PCR results showed that the mRNA expression level of BMAL1 was significantly decreased in liver tissue of the periodontitis group [(0.60±0.04)%] compared to the control group [(1.01±0.07)%] (<i>t=i>4.80, <i>P=i>0.009), while the mRNA expression levels of NF-κB and TNF-α [(1.62±0.12)%, (2.69±0.16)%] were significantly increased compared to the control group [(1.00±0.03)%, (1.03±0.16)%] (<i>P=i>0.008, <i>P=i>0.002); IHC results showed that the protein expression level of BMAL1 in liver tissue of the periodontitis group (averaged optical density, AOD) (11.58±2.15) was down-regulated compared to the control group (AOD) (22.66±1.67) (<i>P=i>0.015), while NF-κB and TNF-α (AOD) (31.77±2.69, 24.31±2.32) were up-regulated compared to the control group (AOD) (19.40±1.82, 11.92±0.94) (<i>P=i>0.019, <i>P=i>0.008). WB results showed that the protein expression level of BMAL1 in liver tissue was down-regulated in the periodontitis group [(0.63±0.10)%] compared to the control group [(1.00±0.06)%] (<i>t=i>3.19, <i>P=i>0.033), while NF-κB and TNF-α [(1.61±0.12)%, (2.82±0.23)%] were up-regulated compared to the control group [(1.00±0.12)%, (1.00±0.11)%] (<i>P=i>0.022, <i>P=i>0.002). TUNEL staining showed increased apoptotic cells in the liver tissue of the periodontitis group of rats compared to the control group. Conclusions: Periodontitis may induce liver injury by down-regulating the BMAL1 expression levels in liver tissue, which in turn activates NF-κB signaling molecules, leading to the elevated levels of inflammation and apoptosis in rat liver.
Animals
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Male
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Rats
;
Alanine Transaminase/metabolism*
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ARNTL Transcription Factors/metabolism*
;
Aspartate Aminotransferases/metabolism*
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Biotin/metabolism*
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Bone Resorption
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Brain
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Chemical and Drug Induced Liver Injury, Chronic
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Cholesterol
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DNA Nucleotidylexotransferase/metabolism*
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Muscles/metabolism*
;
NF-kappa B/metabolism*
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Periodontitis
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Rats, Wistar
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RNA, Messenger/metabolism*
;
Triglycerides
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Tumor Necrosis Factor-alpha/metabolism*
8.Characterization of a family B DNA polymerase from <i>Thermococcus eurythermalisi> A501 and its application in PCR.
Chinese Journal of Biotechnology 2022;38(2):807-819
DNA polymerases are widely used in PCR and play important roles in life science research and related fields. Development of high-performance DNA polymerases is of great commercial interest as the current commercial DNA polymerases could not fully satisfy the requirements of scientific research. In this study, we cloned and expressed a family B DNA polymerase (NCBI accession number TEU_RS04875) from <i>Thermococcus eurythermalisi> A501, characterized its enzymatic property and evaluated its application in PCR. The recombinant Teu-PolB was expressed in <i>E. colii> and purified with affinity chromatography and ion-exchange chromatography. The enzymatic properties of Teu-PolB were characterized using fluorescence-labeled oligonucleotides as substrates. The application potential of Teu-PolB in PCR was evaluated using the phage λ genomic DNA as a template. Teu-PolB has DNA polymerase and 3'→5' exonuclease activities, and is highly thermostable with a half-life of 2 h at 98 ℃. The most suitable PCR buffer is consisted of 50 mmol/L Tris-HCl pH 8.0, 2.5 mmol/L MgCl2, 60 mmol/L KCl, 10 mmol/L (NH4)2SO4, 0.015% Triton X-100 and 0.01% BSA, and the optimal extension temperature is 68 ℃. Under the optimized conditions, a 4 kb target fragment was successfully amplified with an extension rate of 2 kb/min. The yield of the Teu-PolB amplified-DNA was lower than that of <i>Taqi> DNA polymerase, but its extension rate and fidelity was higher than that of <i>Taqi> and <i>Pfui> DNA polymerases. The biochemical properties of Teu-PolB demonstrate that this enzyme can be used in PCR amplification with high thermostability, good salt tolerance, high extension rate and high fidelity.
DNA-Directed DNA Polymerase/genetics*
;
Escherichia coli/genetics*
;
Polymerase Chain Reaction/methods*
;
Temperature
;
Thermococcus/genetics*
9.The E248R protein of African swine fever virus inhibits the cGAS-STING-mediated innate immunity.
Yinguang LIU ; Wenping YANG ; Yuan WEN ; Qingli NIU ; Jifei YANG ; Guiquan GUAN ; Hong YIN ; Haixue ZHENG ; Dan LI ; Zhijie LIU
Chinese Journal of Biotechnology 2022;38(5):1837-1846
We researched the mechanism of African swine fever virus (ASFV) protein E248R in regulating the cGAS-STING pathway. First, we verified via the dual-luciferase reporter assay system that E248R protein inhibited the secretion of IFN-β induced by cGAS-STING or HT-DNA in a dose-dependent manner. The relative quantitative PCR analysis indicated that the overexpression of E248R inhibited HT-DNA-induced transcription of <i>IFN-b1i>, <i>RANTESi>, <i>IL-6i>, and <i>TNF-αi> in PK-15 cells. Next, we found that E248R interacted with STING by co-immunoprecipitation assay and laser confocal microscopy. Finally, we demonstrated that E248R inhibited the expression of STING protein by using Western blotting. We demonstrated for the first time that the E248R protein of ASFV suppressed the host innate immune response via inhibiting STING expression. The results are pivotal in extending the understanding of the ASFV immune escape and can guide the design of vaccines against ASFV.
African Swine Fever Virus/genetics*
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Animals
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DNA
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Immunity, Innate
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Nucleotidyltransferases/metabolism*
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Signal Transduction
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Swine
10.Upregulation of h-TERT and Ki-67 in ectopic endometrium is associated with recurrence of endometriosis.
Jie LUO ; Zhimin SONG ; Tao ZHANG ; Ketan CHU ; Jingyi LI ; Jianhong ZHOU ; Jun LIN
Journal of Zhejiang University. Science. B 2022;23(2):158-163
At present, endometriosis remains a worldwide health burden, with the main symptoms of dysmenorrhea, chronic pelvic pain, and infertility, markedly reducing the quality of life (de Ziegler et al., 2010). Although there is no proof that the disease is associated with high mortality, this disorder can significantly contribute to the deterioration of women's general well-being (McPeak et al., 2018). The main current treatment for endometriosis is surgery to remove endometriotic lesions; however, the recurrence rate following surgical treatment is as high as 21.5% at two years and 40.0%-50.0% at five years post-surgery (Koga et al., 2015). To prevent recurrence, adjuvant treatment with drugs after surgery is recommended to prolong relapse-free intervals. However, it is inconvenient for patients to continuously use such medications in terms of adverse effects and cost (Turk, 2002).
Endometriosis/pathology*
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Endometrium/pathology*
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Female
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Humans
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Ki-67 Antigen/metabolism*
;
Quality of Life
;
Recurrence
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Telomerase/metabolism*
;
Up-Regulation

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