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BackgroundThe telomerase catalytic subunit hTERT is a critical oncogenic driver in nasopharyngeal carcinoma (NPC). The specific role of aloe-emodin (AE) in regulating hTERT in NPC has not been systematically investigated. The regulatory network involving hTERT and its upstream transcription factors, c-Myc and E2F1, offers a promising therapeutic avenue.MethodsBioinformatics was used to analyze hTERT expression and its prognostic significance in head and neck squamous cell carcinoma and nasopharyngeal carcinoma. Molecular docking simulations were conducted to investigate the potential interaction between AE and hTERT. hTERT expression was assessed in normal nasal epithelial cells and NPC cell lines. Effects of AE on hTERT, c-Myc, and E2F1 were measured using qRT-PCR and Western blotting. Telomerase activity was evaluated through TRAP-qPCR and PAGE. hTERT was knocked down using siRNA. Cell proliferation, migration, and invasion were analyzed using CCK-8, EdU, colony formation, and Transwell assays. ROS levels were quantified using DCFH-DA staining. In vivo, a subcutaneous xenograft model was established to assess AE’s anti-tumor efficacy alone and with shRNA-mediated hTERT knockdown. Organ toxicity was evaluated by H&E staining. Tumor tissues were analyzed by immunohistochemistry for hTERT, c-Myc, E2F1, Ki-67, and Cleaved Caspase-3.ResultsBioinformatics analysis revealed elevated hTERT expression in HNSC tissues and NPC cell lines Molecular docking predicted a potential interaction between AE and the catalytic pocket of hTERT. In vitro, AE treatment decreased c-Myc, increased E2F1, and reduced hTERT transcription. AE also reduced telomerase activity, increased ROS levels, and suppressed proliferation, migration, and invasion in NPC cells. In vivo, AE showed anti-tumor activity. Combined with hTERT knockdown, AE produced synergistic tumor suppression and enhanced modulation of the c-Myc/E2F1/hTERT axis and oxidative stress. Immunohistochemistry revealed suppressed proliferation and increased apoptosis in tumor tissues of the combination group. No significant organ toxicity was observed.ConclusionThis study presents the first systematic validation of AE’s anti-NPC effects. These include hTERT suppression, modulation of the c-Myc/E2F1 network, and induction of oxidative stress. These findings suggest a potential therapeutic target and strategy for NPC. The results support the clinical translation of AE.

Telomerase is a reverse transcriptase that maintains telomeres length, compensating for the attrition of chromosomal ends that occurs during each replication cycle. Telomerase is expressed in germ cells and stem cells, whereas it is virtually undetectable in adult somatic cells. On the other hand, telomerase is broadly expressed in the majority of human tumors playing a crucial role in the replicative behavior and immortality of cancer cells. Several studies have demonstrated that telomerase-derived peptides are able to bind to HLA (human leukocyte antigen) class I and class II molecules and effectively activate both CD8+ and CD4+ T cells subsets. Due to its broad and selective expression in cancer cells and its significant immunogenicity, telomerase is considered an ideal universal tumor-associated antigen, and consequently, a very attractive target for anti-cancer immunotherapy. To date, different telomerase targeting immunotherapies have been studied in pre-clinical and clinical settings, these approaches include peptide vaccination and cell-based vaccination. The objective of this review paper is to discuss the role of human telomerase in cancer immunotherapy analyzing recent developments and future perspectives in this field.

Although three-dimensional (3D) co-culture of gingival keratinocytes and fibroblasts-populated collagen gel can mimic 3D structure of in vivo tissue, the uncontrolled contraction of collagen gel restricts its application in clinical and experimental practices. We here established a stable 3D gingival tissue equivalent (GTE) using hTERT-immortalized gingival fibroblasts (hGFBs)-populated collagen gel directly crosslinked with genipin/cytochalasin D and seeding hTERT-immortalized gingival keratinocytes (TIGKs) on the upper surface for a 2-week air–liquid interface co-culture. MTT assay was used to measure the cell viability of GTEs. GTE size was monitored following culture period, and the contraction was analyzed. Immunohistochemical assay was used to analyze GTE structure. qRT-PCR was conducted to examine the mRNA expression of keratinocyte-specific genes. Fifty µM genipin (G50) or combination (G + C) of G50 and 100 nM cytochalasin D significantly inhibited GTE contraction. Additionally, a higher cell viability appeared in GTEs crosslinked with G50 or G + C. GTEs crosslinked with genipin/cytochalasin D showed a distinct multilayered stratified epithelium that expressed keratinocyte-specific genes similar to native gingiva. Collagen directly crosslinked with G50 or G + C significantly reduced GTE contraction without damaging the epithelium. In summary, the TIGKs and hGFBs can successfully form organotypic multilayered cultures, which can be a valuable tool in the research regarding periodontal disease as well as oral mucosa disease. We conclude that genipin is a promising crosslinker with the ability to reduce collagen contraction while maintaining normal cell function in collagen-based oral tissue engineering.

Alternative RNA splicing impacts the majority (>90%) of eukaryotic multi-exon genes, expanding the coding capacity and regulating the abundance of gene isoforms. Telomerase (hTERT) is a key example of a gene that is alternatively spliced during human fetal development and becomes dysregulated in nearly all cancers. Approximately 90% of human tumors use telomerase to synthesize de novo telomere repeats and obtain telomere-dependent cellular immortality. Paradigm shifting data indicates that hTERT alternative splicing, in addition to transcription, plays an important role in the regulation of active telomerase in cells. Our group and others are pursuing the basic science studies to progress this emerging area of telomerase biology. Recent evidence demonstrates that switching splicing of hTERT from the telomerase activity producing full-length hTERT isoform to alternatively spliced, non-coding isoforms may be a novel telomerase inhibition strategy to prevent cancer growth and survival. Thus, the goals of this review are to detail the general roles of telomerase in cancer development, explore the emerging regulatory mechanisms of alternative RNA splicing of the hTERT gene in various somatic and cancer cell types, define the known and potential roles of hTERT splice isoforms in cancer cell biology, and provide insight into new treatment strategies targeting hTERT in telomerase-positive cancers.

Most somatic human cells lack telomerase activity because they do not express the telomerase reverse transcriptase (hTERT) gene. Conversely, most cancer cells express hTERT and are telomerase positive For most tumors it is not clear whether hTERT expression is due to their origin from telomerase positive stem cells or to reactivation of the gene during tumorigenesis. Telomerase negative cells lack detectable cytoplasmic and nuclear hTERT transcripts; in telomerase positive cells 0.2 to 6 mRNA molecules/cell can be detected. This suggests that expression is regulated by changes in the rate of hTERT gene transcription. In tumor cell lines hTERT expression behaves like a recessive trait, indicating that lack of expression in normal cells is due to one or several repressors. Studies with monochromosomal hybrids indicate that several chromosomes may code for such repressors. A number of transcription factors, tumor suppressors, cell cycle inhibitors, cell fate determining molecules, hormone receptors and viral proteins have been implicated in the control of hTERT expression; but these studies have not yet provided a clear explanation for the tumor specific expression of the hTERT gene, and the cis-acting elements which are the targets of repression in normal cells still have to be identified.

Telomerase, an enzyme responsible for the synthesis of telomeres, is activated in many cancer cells and is involved in the maintenance of telomeres. The activity of telomerase allows cancer cells to replicate and proliferate in an uncontrolled manner, to infiltrate tissue, and to metastasize to distant organs. Studies to date have examined the mechanisms involved in the survival of cancer cells as targets for cancer therapeutics. These efforts led to the development of telomerase inhibitors as anticancer drugs, drugs targeting telomere DNA, viral vectors carrying a promoter for human telomerase reverse transcriptase (hTERT) genome, and immunotherapy targeting hTERT. Among these novel therapeutics, this review focuses on immunotherapy targeting hTERT and discusses the current evidence and future perspectives.

Alzheimer’s disease is a progressive neurodegenerative disorder that affects memory and cognitive abilities, affecting millions of people around the world. Current treatments focus on the management of symptoms, as no effective therapy has been approved to modify the underlying disease process. Gene therapy is a promising approach that can offer disease-modifying treatment for AD, targeting various aspects of the pathophysiology of the disease. This review presents a comprehensive overview of the current state of gene therapy research for AD, with a specific focus on clinical trials and preclinical studies that have used nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), apolipoprotein E2 (APOE2), and human telomerase reverse transcriptase (hTERT) as therapeutic gene therapy approaches. These gene targets have shown potential to alleviate the neuropathology of AD in animal studies and have demonstrated feasibility and safety in non-human primates. Despite the failure of the NGF gene therapy approach in clinical trials, we have reviewed and highlighted the reported findings and evaluations from the trials. Furthermore, the review included the conclusions of postmortem brain tissue analysis of AD patients who received NGF gene therapy. The goal is to learn from the failed trials and improve the approach in the future. Although gene therapy shows promise, it faces several challenges and limitations, including optimizing gene delivery methods, enhancing safety and efficacy profiles, and determining long-term results. This review contributes to the growing body of literature on innovative treatments for AD and highlights the need for more research and development to advance gene therapy as a viable treatment option for AD.

Cancer remains a leading global cause of death, with conventional treatments often limited by toxicity and recurrence. Recent advances in gene therapy and nanodrug delivery offer new avenues for precision oncology. Human telomerase reverse transcriptase (hTERT) and glutathione peroxidase 4 (GPX4) are overexpressed in many cancers and linked to apoptosis and ferroptosis, respectively. Here, we developed a manganese dioxide nanosheet (MnO2-NS) probe co-loaded with antisense oligonucleotides targeting hTERT and GPX4 mRNA to synergistically down-regulate both genes and induce dual cell death pathways. The probe, assembled via adsorption of fluorescently labeled antisense strands, showed controllable release in the presence of glutathione (GSH). Cellular uptake and antisense release were confirmed in multiple cancer cell lines. The MnO2-NS probe significantly suppressed cell proliferation, outperforming single-target or carrier-only controls. Molecular analyses confirmed reduced hTERT and GPX4 expression, along with GSH depletion, ROS accumulation, and elevated lipid peroxidation—collectively promoting enhanced cancer cell death. In summary, this MnO2-NS-based co-delivery system enables synergistic gene silencing and GSH depletion, enhancing antitumor efficacy and providing a promising strategy for multifunctional nanotherapy.

Bladder cancer (BC) has a 70% telomerase reverse transcriptase (TERT or hTERT in humans) promoter mutation prevalence, commonly at −124 base pairs, and this is associated with increased hTERT expression and poor patient prognosis. We inserted a green fluorescent protein (GFP) tag in the mutant hTERT promoter allele to create BC cells expressing an hTERT-GFP fusion protein. These cells were used in a fluorescence-activated cell sorting–based pooled CRISPR-Cas9 Kinome knockout genetic screen to identify tripartite motif containing 28 (TRIM28) and TRIM24 as regulators of hTERT expression. TRIM28 activates, while TRIM24 suppresses, hTERT transcription from the mutated promoter allele. TRIM28 is recruited to the mutant promoter where it interacts with TRIM24, which inhibits its activity. Phosphorylation of TRIM28 through the mTOR complex 1 (mTORC1) releases it from TRIM24 and induces hTERT transcription. TRIM28 expression promotes in vitro and in vivo BC cell growth and stratifies BC patient outcome. mTORC1 inhibition with rapamycin analog Ridaforolimus suppresses TRIM28 phosphorylation, hTERT expression, and cell viability. This study may lead to hTERT-directed cancer therapies with reduced effects on normal progenitor cells.

Extracellular Vesicles (EVs) from Mesenchymal Stromal Cells (MSCs) are promising cell‐free therapeutics due to their ability to modulate immune responses, promote tissue repair and replicate many benefits of their parental cells. However, developing standardised, clinically translatable MSC‐EV preparations remains difficult because of biological and technical variability. Factors such as cell source, donor differences, passage number and culture conditions affect EV yield and function, while enrichment methods, purity and media composition further complicate interpretation of EV‐specific effects. Although prior studies have explored isolation methods and serum contaminants, the impact of different collection media on EV bioactivity is poorly understood. Here, we used hTERT‐immortalised MSCs, which preserve the therapeutic properties of primary MSCs, to minimise cellular variability. EVs were collected in four different xeno‐free media, enriched via Tangential Flow Filtration (TFF) and assessed in terms of their anti‐inflammatory, anti‐fibrotic, gap closure and proliferative potential compared with unconditioned, TFF processed collection media. Our results demonstrate that collection media significantly affect MSC‐EV biological and functional properties, highlighting the need to carefully select media for standardised EV production. This study advances standardisation in EV research and supports the development of consistent, clinically relevant MSC‐EV products.