BACKGROUND: P16 inactivation is frequently accompanied by telomerase reverse transcriptase ( TERT ) amplification in human cancer genomes. P16 inactivation by DNA methylation often occurs automatically during immortalization of normal cells by TERT . However, direct evidence remains to be obtained to support the causal effect of epigenetic changes, such as P16 methylation, on cancer development. This study aimed to provide experimental evidence that P16 methylation directly drives cancer development. METHODS: A zinc finger protein-based P16 -specific DNA methyltransferase (P16-Dnmt) vector containing a "Tet-On" switch was used to induce extensive methylation of P16 CpG islands in normal human fibroblast CCD-18Co cells. Battery assays were used to evaluate cell immortalization and transformation throughout their lifespan. Cell subcloning and DNA barcoding were used to track the diversity of cell evolution. RESULTS: Leaking P16-Dnmt expression (without doxycycline-induction) could specifically inactivate P16 expression by DNA methylation. P16 methylation only promoted proliferation and prolonged lifespan but did not induce immortalization of CCD-18Co cells. Notably, cell immortalization, loss of contact inhibition, and anchorage-independent growth were always prevalent in P16-Dnmt&TERT cells, indicating cell transformation. In contrast, almost all TERT cells died in the replicative crisis. Only a few TERT cells recovered from the crisis, in which spontaneous P16 inactivation by DNA methylation occurred. Furthermore, the subclone formation capacity of P16-Dnmt&TERT cells was two-fold that of TERT cells. DNA barcoding analysis showed that the diversity of the P16-Dnmt&TERT cell population was much greater than that of the TERT cell population. CONCLUSION P16 methylation drives TERT -mediated immortalization and transformation of normal human cells that may contribute to cancer development.
Humans ; Telomerase/genetics* ; DNA Methylation/physiology* ; Fibroblasts/cytology* ; Cyclin-Dependent Kinase Inhibitor p16/metabolism* ; Cell Line ; Cell Transformation, Neoplastic/genetics*

OBJECTIVE: To summarize the clinical characteristics, diagnosis, treatment and prognosis of dyskeratosis congenita (DC) in children, and to provide clinical experience for the diagnosis and treatment of DC. METHODS: The clinical data of children with dyskeratosis congenital admitted to Children's Hospital of Soochow University from May 2016 to May 2024 were retrospectively analyzed. Whole exome sequencing (WES) was performed, the patients were followed up and the related literature was reviewed. RESULTS: A total of 4 patients were enrolled. There were 1 male and 3 females. Two patients had spontaneous TINF2 mutation, one had TERT mutation, and one had DKC1 mutation. All of them had bone marrow hypoplasia. Two patients underwent allogeneic hematopoietic stem cell transplantation, and both had good engraftment. Anti-rejection drugs were stopped, and they survived more than 5 years of follow-up. One patient was followed up in outpatient department, and another patient was scheduled to undergo hematopoietic stem cell transplantation. CONCLUSION The onset of dyskeratosis congenita in children is insidious, so genetic diagnosis is particularly important. c.853_861delGTCATGCTG (p.285-287del) was a new mutation site of TINF2, which expanded the gene mutation spectrum of DC. Hematopoietic stem cell transplantation is an effective treatment for bone marrow failure, and the treatment of other organ complications depends on further genetic exploration.
Humans ; Dyskeratosis Congenita/therapy* ; Hematopoietic Stem Cell Transplantation ; Male ; Mutation ; Female ; Retrospective Studies ; Telomerase/genetics* ; Telomere-Binding Proteins/genetics* ; Child ; Cell Cycle Proteins/genetics* ; Nuclear Proteins/genetics* ; Child, Preschool ; Prognosis ; Exome Sequencing

China is a high-incidence region for gastric cancer globally. The disease is characterized by a high morbidity rate, low early diagnostic rate, and poor long-term outcomes, imposing a significant burden on both patients and society. Therefore, exploring the pathogenesis of gastric cancer, developing novel therapeutic strategies, and identifying new drug targets is of great importance. Telomerase expression is broadly associated with cancer cell targeting, and its up-regulation is one of the key factors driving the initiation and progression of gastric cancer. Additionally, telomerase is intricately involved in the regulation of autophagy and autophagy-associated cell death. While autophagy can induce chemoresistance, excessive autophagy may lead to cell death, which also constitutes one of the mechanisms of chemotherapy. Telomerase not only directly contributes to gastric cancer pathogenesis but also indirectly influences its development and treatment by modulating autophagy and autophagic cell death. Therefore, telomerase holds promise as a novel therapeutic target in gastric cancer.
Humans ; Stomach Neoplasms/genetics* ; Telomerase/genetics* ; Autophagy/physiology*

One of the basic questions in the aging field is whether there is a fundamental difference between the aging of lower invertebrates and mammals. A major difference between the lower invertebrates and mammals is the abundancy of noncoding RNAs, most of which are not conserved. We have previously identified a noncoding RNA Terc-53 that is derived from the RNA component of telomerase Terc. To study its physiological functions, we generated two transgenic mouse models overexpressing the RNA in wild-type and early-aging Terc-/- backgrounds. Terc-53 mice showed age-related cognition decline and shortened life span, even though no developmental defects or physiological abnormality at an early age was observed, indicating its involvement in normal aging of mammals. Subsequent mechanistic study identified hyaluronan-mediated motility receptor (Hmmr) as the main effector of Terc-53. Terc-53 mediates the degradation of Hmmr, leading to an increase of inflammation in the affected tissues, accelerating organismal aging. adeno-associated virus delivered supplementation of Hmmr in the hippocampus reversed the cognition decline in Terc-53 transgenic mice. Neither Terc-53 nor Hmmr has homologs in C. elegans. Neither do arthropods express hyaluronan. These findings demonstrate the complexity of aging in mammals and open new paths for exploring noncoding RNA and Hmmr as means of treating age-related physical debilities and improving healthspan.
Animals ; Mice ; RNA, Untranslated/metabolism* ; Aging/genetics* ; Mice, Transgenic ; Telomerase/metabolism* ; RNA/genetics* ; Hippocampus/metabolism* ; Humans ; Mice, Inbred C57BL

Conventional cancer therapies, such as radiotherapy and chemotherapy, often damage normal cells and may induce new tumors. Oncolytic viruses (OVs) selectively target tumor cells while sparing normal cells. Most OVs used in clinical trials have been genetically engineered to enhance their ability to target tumor cells and activate immune responses. To develop a specific OV-based approach for treating cervical cancer, this study constructed an oncolytic adenovirus that delivered a base editor targeting oncogenes to achieve efficient killing of tumor cells through inhibiting tumor growth and directly lysing tumor cells. We utilized the human telomerase reverse transcriptase (TERT) promoter to drive the expression of adenovirus early region 1A (E1A) and successfully constructed the P-hTERT-E1A-GFP vector, which was validated for its activity in cervical cancer cells. Given the critical role of the MYC oncogene in the research of oncology, identifying efficient editing sites for the MYC oncogene is a key step in this study.Three MYC-targeting gRNAs were engineered and co-delivered with ABE8e base editor plasmids into HEK293T cells. Following puromycin selection, Sanger sequencing demonstrated differential editing efficiencies: MYC-1 (43%), MYC-2 (25%), and MYC-3 (35%), identifying MYC-1 as the most efficient editing locus. By constructing the P-ABEs-hTERT-E1A-GFP and P-MYC gRNA-hTERT-E1A-GFP vectors, we successfully packaged the virus and confirmed its specificity and efficacy. The experimental results demonstrate that this novel oncolytic adenovirus effectively inhibits the growth of HeLa cells in vitro, providing new experimental evidence and potential strategies for treating cervical cancer based on the HeLa cell model.
Humans ; Uterine Cervical Neoplasms/pathology* ; Oncolytic Viruses/genetics* ; Female ; HEK293 Cells ; Oncolytic Virotherapy/methods* ; Adenoviridae/genetics* ; Gene Editing/methods* ; Telomerase/genetics* ; Adenovirus E1A Proteins/genetics* ; Genetic Vectors/genetics* ; HeLa Cells

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 ; Adult ; Middle Aged ; Aged ; Female ; Neoplasms, Fibroepithelial/pathology* ; Phyllodes Tumor/genetics* ; Stromal Cells ; Fibroadenoma/pathology* ; Breast Neoplasms/pathology* ; Mutation ; Telomerase/genetics*

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 in situ 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 ; Mice ; Telomerase/metabolism* ; Carcinoma, Hepatocellular/genetics* ; Liver Neoplasms/genetics* ; Telomere Shortening ; In Situ Hybridization, Fluorescence ; Mice, Nude ; Telomere/pathology* ; Carcinogenesis

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 (P>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 (P<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 ; Urinary Bladder Neoplasms/genetics* ; Carcinoma, Transitional Cell/pathology* ; Urinary Bladder/pathology* ; Diagnosis, Differential ; Retrospective Studies ; Mutation ; Cystitis/genetics* ; Neoplasms, Glandular and Epithelial/diagnosis* ; Papilloma/diagnosis* ; Telomerase/genetics*

OBJECTIVE: To investigate the cytotoxic effect and its mechanism of the micromolecule compound on the leukemia cells. METHODS: The cytotoxic effects of 28 Nilotinib derivatives on K562, KA, KG, HA and 32D cell lines were detected by MTT assays, and the compound Nilo 22 was screen out. Cell apoptosis and cell cycle on leukemia cells were detected by flow cytometry. The effect of compound screened out on leukemogenesis potential of MLL-AF9 leukemia mice GFP RESULTS: Nilo 22 serves as the most outstanding candidate out of 28 Nilotinib derivatives, which impairs leukemia cell lines, but spares normal hematopoietic cell line. Comparing with Nilotinib, Nilo 22 could induce the apoptosis of GFP CONCLUSION Nilo 22 shows a significant cytotoxic effect on mice and human leukemia cells, especially for drug resistance cells. Nilo 22 is a promising anti-leukemia agent to solve the common clinical problems of drug resistance and relapse of leukemia.
Animals ; Apoptosis/drug effects* ; Cell Cycle/drug effects* ; Cell Line, Tumor ; Humans ; Leukemia ; Mice ; Myeloid-Lymphoid Leukemia Protein/genetics* ; Telomerase/metabolism* ; Telomere/metabolism*

Adult ; China ; Dimethoate/analogs & derivatives* ; Farmers/statistics & numerical data* ; Female ; Humans ; Male ; Middle Aged ; Occupational Exposure ; Pesticides/adverse effects* ; Polymorphism, Single Nucleotide ; Telomerase/genetics* ; Telomere/physiology*