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*

Copy number alteration (CNA) is a significant genetic change in pediatric B-cell acute lymphoblastic leukemia (B-ALL), with CDKN2A/B deletions, PAX5 deletions, and IKZF1 deletions being the most common. Recent studies have increasingly highlighted the potential prognostic significance of these gene deletions and multiple co-deletions in pediatric B-ALL. This paper reviews the main detection methods for CNA, as well as the prognostic characteristics and treatment approaches for common CNA in pediatric B-ALL.
Humans ; DNA Copy Number Variations ; Child ; PAX5 Transcription Factor/genetics* ; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics* ; Cyclin-Dependent Kinase Inhibitor p15/genetics* ; Ikaros Transcription Factor/genetics* ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics* ; Gene Deletion ; Cyclin-Dependent Kinase Inhibitor p16/genetics* ; Prognosis

This paper reports the case of a 10-month-old male infant with Beckwith-Wiedemann syndrome (BWS) who presented with a reducible right inguinal mass and an empty scrotum for 10 months and was admitted for elective surgery. Preoperative ultrasonography revealed a right adrenal mass, which was pathologically diagnosed as ganglioneuroblastoma (GNB) after surgical excision. The patient exhibited characteristic features of BWS, including omphalocele, flame-shaped nevus on the forehead, bilateral earlobe creases, and embryonal tumor. Next-generation sequencing identified a heterozygous mutation in the CDKN1C gene (chr11:2905365), confirming the diagnosis of BWS. Early diagnosis, standardized management, and tumor surveillance are crucial for improving prognosis in children with BWS. Ultrasonography enables early detection of tumors and informs clinical decision-making regarding intervention.
Humans ; Beckwith-Wiedemann Syndrome/genetics* ; Male ; Ganglioneuroblastoma/complications* ; Infant ; Cyclin-Dependent Kinase Inhibitor p57/genetics* ; Mutation

OBJECTIVE: To investigate the relationship between CDKN2A copy number deletion and clinical features of patients with diffuse large B-cell lymphoma (DLBCL) and its prognostic value. METHODS: 155 newly diagnosed DLBCL patients with complete clinical data in the Department of Hematology of People's Hospital of Xinjiang Uygur Autonomous Region from March 2009 to March 2022 were included, formalin-fixed paraffin-embedded tumor tissues were obtained and DNA was extracted from them, and next-generation sequencing technology was applied to target sequencing including 475 lymphoma-related genes, the relationship between CDKN2A copy number deletion and clinical features, high-frequency mutated genes and overall survival (OS) of DLBCL patients were analyzed. RESULTS: CDKN2A copy number deletion was present in 12.9% (20/155) of 155 DLBCL patients, grouped according to the presence or absence of copy number deletion of CDKN2A, and a higher proportion of patients with IPI≥3 were found in the CDKN2A copy number deletion group compared to the group with no CDKN2A copy number deletion (80% vs 51.5%, P =0.015) and were more likely to have bulky disease (20% vs 5.2%, P =0.037). Survival analysis showed that the 5-year OS of patients in the CDKN2A copy number deletion group was significantly lower than that of the non-deletion group (51.3% vs 69.2%, P =0.047). Multivariate Cox analysis showed that IPI score≥3 (P =0.007), TP53 mutation (P =0.009), and CDKN2A copy number deletion (P =0.04) were independent risk factors affecting the OS of DLBCL patients. CONCLUSION CDKN2A copy number deletion is an independent risk factor for OS in DLBCL, and accurate identification of CDKN2A copy number deletion can predict the prognosis of DLBCL patients.
Humans ; Lymphoma, Large B-Cell, Diffuse/genetics* ; Prognosis ; Cyclin-Dependent Kinase Inhibitor p16/genetics* ; DNA Copy Number Variations ; Female ; Male ; Middle Aged ; Gene Deletion ; Adult ; Aged

OBJECTIVE: To investigate the effects and mechanisms of hydroxysafflor yellow A (HSYA) on replicative senescence in human umbilical cord mesenchymal stem cells (hUC-MSCs). METHODS: hUC-MSCs were cultured to construct a replicative senescence model through continuous amplification in vitro. Cells at passage 2 served as the control group, while cells at passage 10 were designated as the senescence group. The senescent cells were cultured in a culture medium containing HSYA. Cell viability was detected by the CCK-8 assay, and cell confluence was analyzed using the Incucyte S3 live-cell analysis system. The optimal concentration and time point were determined and utilized for subsequent experiments. Senescent cells were pretreated with 0.01 mg/ml HSYA, and the proportion of senescence-associated β-galactosidase (SA-β-gal) positive cells was detected to assess the senescence state. The relative telomere length was detected by qPCR. Reactive oxygen species (ROS) levels were measured using the fluorescent probe DCFH-DA. Mitochondrial membrane potential was assessed by JC-1 staining. The expression of p53, p16, p21, OCT4, and SOX2 genes was detected by qPCR. The expression of p16, p53, OCT4, and SOX2 proteins was analyzed by Western blot. RESULTS: HSYA significantly decreased the SA-β-gal positive staining rate, inhibited telomere attrition, reduced the ROS accumulation, increased mitochondrial membrane potential in senescent cells. Additionally, HSYA downregulated the expression of p53 and p16, and upregulated the expression of OCT4. HSYA decreased p16 protein level and increased OCT4 and SOX2 protein levels. CONCLUSION HSYA may ameliorate replicative senescence in hUC-MSCs by modulating the p53 and p16 signaling pathways and suppressing oxidative stress.
Humans ; Mesenchymal Stem Cells/drug effects* ; Cellular Senescence/drug effects* ; Chalcone/pharmacology* ; Oxidative Stress/drug effects* ; Quinones/pharmacology* ; Umbilical Cord/cytology* ; Reactive Oxygen Species/metabolism* ; Cells, Cultured ; Cyclin-Dependent Kinase Inhibitor p16/metabolism* ; Tumor Suppressor Protein p53/metabolism* ; Membrane Potential, Mitochondrial ; Cell Proliferation

OBJECTIVES: To investigate the expression of CDKN3 in gastric cancer and its impact on prognosis of gastric cancer patients. METHODS: We analyzed CDKN3 expression in clinical specimens from 114 gastric cancer patients and assessed its association with 5-year postoperative survival of the patients. GO and KEGG enrichment analyses were used to predict the biological function and possible mechanism of CDKN3. The effects of lentivirus-mediated CDKN3 knockdown on biological behaviors of gastric cancer cells were evaluated using Transwell assay, CCK-8 assay, TUNEL staining, flow cytometry, and Western blotting. RESULTS: CDKN3 expression was significantly higher in gastric cancer tissues than in the adjacent tissues with significant correlations with CEA level, CA19-9 level, and T and N staging (P<0.05). High CDKN3 expression was an independent risk factor affecting 5-year postoperative survival of the patients and predictive for long-term prognosis (P<0.01). Enrichment analyses suggested a probable association of CDKN3 with apoptosis. In MGC-803 cells, CDKN3 knockdown significantly lowered migration and invasion capacities of the cells, while CDKN3 overexpression produced the opposite effects. TUNEL staining revealed a significantly lower level of cell apoptosis in gastric cancer tissues than in adjacent tissues (P<0.01). CDKN3 knockdown obviously inhibited proliferation and increased apoptosis of MGC-803 cells. CDKN3 overexpression down-regulated the expressions of p53, p21 and Bax and up-regulated the expressions of p-p65 and Bcl-2. CONCLUSIONS CDKN3 is highly expressed in gastric cancer tissues and affects patient prognosis. CDKN3 overexpression promotes proliferation, invasion and migration and suppressed apoptosis of gastric cancer cells possibly through the p53/NF-κB signaling pathway.
Humans ; Stomach Neoplasms/pathology* ; Apoptosis ; Signal Transduction ; Tumor Suppressor Protein p53/metabolism* ; Cell Movement ; Cell Line, Tumor ; NF-kappa B/metabolism* ; Prognosis ; Cyclin-Dependent Kinase Inhibitor Proteins/metabolism* ; Cell Proliferation ; Neoplasm Invasiveness ; Male ; Female ; Dual-Specificity Phosphatases

OBJECTIVE: To observe the therapeutic effects and underlying mechanism of baicalin against colon cancer. METHODS: The effects of baicalin on the proliferation and growth of colon cancer cells MC38 and CT26. WT were observed and predicted potential molecular targets of baicalin for colon cancer therapy were studied by network pharmacology. Furthermore, molecular docking and drug affinity responsive target stability (DARTS) analysis were performed to confirm the interaction between potential targets and baicalin. Finally, the mechanisms predicted by in silico analyses were experimentally verified in-vitro and in-vivo. RESULTS: Baicalin significantly inhibited proliferation, invasion, migration, and induced apoptosis in MC38 and CT26 cells (all P<0.01). Additionally, baicalin caused cell cycle arrest at the S phase, while the G₀/G₁ phase was detected in the tiny portion of the cells. Subsequent network pharmacology analysis identified 6 therapeutic targets associated with baicalin, which potentially affect various pathways including 39 biological processes and 99 signaling pathways. In addition, molecular docking and DARTS predicted the potential binding of baicalin with cyclin dependent kinase inhibitor 2A (CDKN2A), protein kinase B (AKT), caspase 3, and mitogen-activated protein kinase (MAPK). In vitro, the expressions of CDKN2A, MAPK, and p-AKT were suppressed by baicalin in MC38 and CT26 cells. In vivo, baicalin significantly reduced the tumor size and weight (all P<0.01) in the colon cancer mouse model via inactivating p-AKT, CDKN2A, cyclin dependent kinase 4, cyclin dependent kinase 2, interleukin-1, tumor necrosis factor α, and activating caspase 3 and mouse double minute 2 homolog signaling (all P<0.05). CONCLUSION Baicalin suppressed the CDKN2A protein level to prevent colon cancer and could be used as a therapeutic target for colon cancer.
Flavonoids/pharmacology* ; Colonic Neoplasms/prevention & control* ; Animals ; Cell Line, Tumor ; Molecular Docking Simulation ; Cell Proliferation/drug effects* ; Apoptosis/drug effects* ; Cyclin-Dependent Kinase Inhibitor p16/metabolism* ; Mice ; Mice, Inbred BALB C ; Cell Movement/drug effects* ; Humans ; Gene Expression Regulation, Neoplastic/drug effects* ; Cell Cycle Checkpoints/drug effects*

The maintenance of hematopoietic stem cells (HSCs) is a complex process involving numerous cell-extrinsic and -intrinsic regulators. The first member of the cyclin-dependent kinase family of inhibitors to be identified, p21, has been reported to perform a wide range of critical biological functions, including cell cycle regulation, transcription, differentiation, and so on. Given the previous inconsistent results regarding the functions of p21 in HSCs in a p21-knockout mouse model, we employed p21-tdTomato (tdT) mice to further elucidate its role in HSCs during homeostasis. The results showed that p21-tdT+ HSCs exhibited increased self-renewal capacity compared to p21-tdT- HSCs. Zbtb18, a transcriptional repressor, was upregulated in p21-tdT+ HSCs, and its knockdown significantly impaired the reconstitution capability of HSCs. Furthermore, p21 interacted with ZBTB18 to co-repress the expression of cKit in HSCs and thus regulated the self-renewal of HSCs. Our data provide novel insights into the physiological role and mechanisms of p21 in HSCs during homeostasis independent of its conventional role as a cell cycle inhibitor.
Animals ; Hematopoietic Stem Cells/cytology* ; Cyclin-Dependent Kinase Inhibitor p21/genetics* ; Mice ; Cell Self Renewal ; Repressor Proteins/genetics* ; Mice, Inbred C57BL ; Mice, Knockout ; Humans ; Gene Expression Regulation

OBJECTIVE: N6-methyladenosine (m ⁶A) is a common epigenetic modification in eukaryotes. In this study, we explore the potential impact of m ⁶A-associated single nucleotide polymorphisms (m ⁶A-SNPs) on heart failure (HF). METHODS: Data from genome-wide association studies (GWAS) investigating HF in humans and from m ⁶A-SNPs datasets were used to identify HF-associated m ⁶A-SNPs. Their functions were explored using expression quantitative trait locus (eQTL), gene expression, and gene enrichment analyses. Mediation protein quantitative trait locus (pQTL)-Mendelian randomization (MR) was used to investigate the potential mechanism between critical protein levels and risk factors for HF. RESULTS: We screened 44 HF-associated m ⁶A-SNPs, including 10 m ⁶A-SNPs that showed eQTL signals and differential expressions in HF. The SNP rs1801270 in CDKN1A showed the strongest association with HF ( P = 7.75 × 10 ^-6). Additionally, MR verified the genetic association between the CDKN1A protein and HF, as well as the mediating effect of blood pressure (BP) in this pathway. Higher circulating level of CDKN1A was associated with a lower risk of HF (odds ratio [ OR] = 0.82, 95% confidence interval [ CI]: 0.69 to 0.99). The proportions of hypertension, systolic BP, and diastolic BP were 48.10%, 28.94%, and 18.02%, respectively. Associations of PDIA6 ( P = 1.30 × 10 ^-2) and SMAD3 ( P = 4.80 × 10 ^-2) with HF were also detected. CONCLUSION Multiple HF-related m ⁶A-SNPs were identified in this study. Genetic associations of CDKN1A and other proteins with HF and its risk factors were demonstrated, providing new ideas for further exploration of the molecular mechanisms of HF.
Humans ; Polymorphism, Single Nucleotide ; Heart Failure/genetics* ; Mendelian Randomization Analysis ; Genome-Wide Association Study ; Cyclin-Dependent Kinase Inhibitor p21/metabolism* ; Quantitative Trait Loci ; Adenosine/metabolism* ; Male ; Female ; Genetic Predisposition to Disease

Aging is an independent risk factor for chronic diseases in the elderly, and understanding aging mechanisms is one of the keys to achieve early prevention and effective intervention for the diseases. Aging process is dynamic and systemic, making it difficult for mechanistic study. With recent advances in aging biomarkers and development of live-imaging technologies, more and more reporter mouse models have been generated, which can live monitor the aging process, and help investigate aging mechanisms at systemic level and develop intervention strategies. This review summarizes recent advances in live-imaging aging reporter mouse models based on widely used aging biomarkers (p16^Ink4a, p21^Waf1/Cip1, p53 and Glb1), and discusses their applications in aging research.
Humans ; Animals ; Mice ; Aged ; Aging ; Cyclin-Dependent Kinase Inhibitor p16/metabolism* ; Cyclin-Dependent Kinase Inhibitor p21/metabolism* ; Biomarkers ; Tumor Suppressor Protein p53