1.Targeting WEE1: a rising therapeutic strategy for hematologic malignancies.
Hao-Bo LI ; Thekra KHUSHAFA ; Chao-Ying YANG ; Li-Ming ZHU ; Xing SUN ; Ling NIE ; Jing LIU
Acta Physiologica Sinica 2025;77(5):839-854
Hematologic malignancies, including leukemia, lymphoma, and multiple myeloma, are hazardous diseases characterized by the uncontrolled proliferation of cancer cells. Dysregulated cell cycle resulting from genetic and epigenetic abnormalities constitutes one of the central events. Importantly, cyclin-dependent kinases (CDKs), complexed with their functional partner cyclins, play dominating roles in cell cycle control. Yet, efforts in translating CDK inhibitors into clinical benefits have demonstrated disappointing outcomes. Recently, mounting evidence highlights the emerging significance of WEE1 G2 checkpoint kinase (WEE1) to modulate CDK activity, and correspondingly, a variety of therapeutic inhibitors have been developed to achieve clinical benefits. Thus, WEE1 may become a promising target to modulate the abnormal cell cycle. However, its function in hematologic diseases remains poorly elucidated. In this review, focusing on hematologic malignancies, we describe the biological structure of WEE1, emphasize the latest reported function of WEE1 in the carcinogenesis, progression, as well as prognosis, and finally summarize the therapeutic strategies by targeting WEE1.
Humans
;
Protein-Tyrosine Kinases/physiology*
;
Hematologic Neoplasms/drug therapy*
;
Cell Cycle Proteins/antagonists & inhibitors*
;
Nuclear Proteins/antagonists & inhibitors*
;
Cyclin-Dependent Kinases
;
Molecular Targeted Therapy
;
Animals
2.Research progress on the regulation of Hippo -YAP signaling pathway in osteoarthritis.
Xi-Yao TAI ; De-Cai HOU ; Jiang ZHANG ; Xiao-Lei DENG
China Journal of Orthopaedics and Traumatology 2025;38(7):759-764
Osteoarthritis (OA) is the most common degenerative joint disease. Its pathological process is related to inflammatory response, chondrocyte apoptosis, and cartilage degeneration. Hippo-yes-associate protein(YAP) signaling pathway plays an important role in mediating organ size and tissue homeostasis. In recent years, the key effector protein YAP in the Hippo-YAP pathway has become a research hotspot in osteoarthritis. This article introduces the activation process of Hippo-YAP signaling pathway and the biological role of YAP. It reviews the progress of YAP in regulating osteoarthritis by influencing the proliferation and differentiation of mesenchymal stem cells and the proliferation, differentiation, and apoptosis of articular chondrocytes. It analyzed the problems encountered in YAP research in OA, introduces the research potential of YAP in other orthopedic diseases, and provides new ideas for subsequent research in Osteoarthritis.
Osteoarthritis/metabolism*
;
Humans
;
Signal Transduction
;
Protein Serine-Threonine Kinases/physiology*
;
Hippo Signaling Pathway
;
YAP-Signaling Proteins
;
Adaptor Proteins, Signal Transducing/physiology*
;
Animals
;
Transcription Factors
;
Chondrocytes/cytology*
;
Cell Cycle Proteins
3.Research on the inhibitory effects of evodiamine on activated T cell proliferation.
Jianan TANG ; Xingyan LUO ; Jingjing HE ; Xiaoxin ZENG ; Yang LIU ; Yi LAI
Chinese Journal of Cellular and Molecular Immunology 2025;41(6):524-530
Objective To explore the characteristics of the inhibitory effect of Evodiamine on the proliferation of activated T cells. Methods Mononuclear cells from peripheral blood (PBMCs) were obtained from healthy donors through density gradient centrifugation, and T cells were subsequently purified by using immunomagnetic bead separation. T cell activation was induced by employing anti-human CD3 and anti-human CD28 antibodies. T cells were treated with different concentrations of EVO (0.37, 1.11, 3.33, and 10)μmol/L. Flow cytometry was applied to evaluate the proliferation index, apoptosis rate, viability, CD25 expression levels, and cell cycle distribution of T cells. The expression levels of cytokines IL-2, IL-17A, IL-4, and IL-10 were quantified by using ELISA. Results 1.11, 3.33 and 10 μmol/L EVO effectively inhibited the proliferation of activated T cells, with an IC50 of (1.5±0.3)μmol/L. EVO did not induce apoptosis in activated T cells and affect the survival rate of resting T cells. EVO did not affect the expression of CD25 and the secretion of IL-2 in activated T cells. EVO arrested the T cell cycle at the G2/M phase, resulting in an increase in G2/M phase cells, and exhibited a concentration-dependent effect. EVO did not affect the secretion of IL-4, IL-10 by activated T cells, but significantly inhibited the secretion of IL-17A. Conclusion EVO did not significantly affect the activation process of T cells but inhibited T cell proliferation by arresting the cell cycle at the G2/M phase and significantly suppressed the secretion of the pro-inflammatory cytokine IL-17A, which suggests that EVO has the potential to serve as a lead compound for the development of low-toxicity and high-efficiency immunosuppressants and elucidates the mechanisms underlying the anti-inflammatory and immunomodulatory effects of the traditional Chinese medicine Evodia rutaecarpa.
Humans
;
Cell Proliferation/drug effects*
;
Quinazolines/pharmacology*
;
T-Lymphocytes/metabolism*
;
Lymphocyte Activation/drug effects*
;
Apoptosis/drug effects*
;
Interleukin-4/metabolism*
;
Interleukin-10/metabolism*
;
Interleukin-2 Receptor alpha Subunit/metabolism*
;
Interleukin-17/metabolism*
;
Interleukin-2/metabolism*
;
Cell Cycle/drug effects*
;
Cells, Cultured
4.Expression and Biological Function of SPOP in Acute Myeloid Leukemia.
Xue-Ying WAN ; Jing XU ; Xiao-Li LIU ; Hong-Wei WANG
Journal of Experimental Hematology 2025;33(1):32-38
OBJECTIVE:
To study the expression of SPOP in patients with acute myeloid leukemia (AML) and its effect on proliferation, apoptosis and cycle of AML cells.
METHODS:
RT-qPCR was used to detect the expression of SPOP mRNA in bone marrow samples of patients with newly diagnosed AML and normal controls. The stable overexpression of SPOP in AML cell lines THP-1 and U937 were constructed by liposome transfection. The effect of SPOP on cell proliferation was detected by CCK-8, and the effect of SPOP on apoptosis and cell cycle was detected by flow cytometry. The expressions of anti-apoptotic protein Bcl-2 and apoptotic protein Bax, Caspase3 were detected by Western blot.
RESULTS:
The median expression level of SPOP mRNA in normal control group was 0.993 1(0.6303, 1.433), while that in AML group was 0.522 1(0.242 2, 0.723 7). The expression level of SPOP in AML group was significantly lower than that in normal control group ( P < 0.001). After the overexpression of SPOP, the proportion of apoptotic cells in the U937 overexpression group and THP-1 overexpression group was 10.9%±0.3% and 4.6%±015%, which were higher than 8.9%±0.3% and 3.0%±0.30% in the Empty Vector group, respectively (both P < 0.05). The expression of Caspase3 in U937 overexpression group and THP-1 overexpression group was 1.154±0.086 and 1.2±0.077, which were higher than 1 in Empty Vector group, respectively (both P < 0.05). The ratio of Bax/Bcl-2 in U937 overexpression group and THP-1 overexpression group was 1.328±0.057 and 1.669±0.15, which were higher than 1 in Empty Vector group, respectively (both P < 0.05). In the cell proliferation experiment, the number of cells in the U937 overexpression group and THP-1 overexpression group were both slightly lower than those in the Empty Vector group, but the differences were not statistically significant (P >0.05). In the cell cycle experiment, the proportion of G1 cells in the U937 overexpression group and THP-1 overexpression group were both slightly higher than those in the Empty Vector group, but the differences were not statistically significant (P >0.05).
CONCLUSION
SPOP can promote the apoptosis of leukemic cells, and its mechanism may be related to down-regulation of Bcl-2 expression and up-regulation of Bax and Caspase3 expression.
Humans
;
Leukemia, Myeloid, Acute/pathology*
;
Apoptosis
;
Repressor Proteins/genetics*
;
Cell Proliferation
;
Nuclear Proteins/genetics*
;
Cell Cycle
;
Proto-Oncogene Proteins c-bcl-2/metabolism*
;
Caspase 3/metabolism*
;
bcl-2-Associated X Protein/metabolism*
;
U937 Cells
;
Cell Line, Tumor
;
RNA, Messenger/genetics*
5.Clinical Analysis of Dyskeratosis Congenita in Children.
Wen-Qi LU ; Shao-Yan HU ; Jing GAO ; Wei GAO ; Jun-Jie FAN
Journal of Experimental Hematology 2025;33(3):906-912
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
6.Effects of Down-regulation of NCL Expression on the Biological Behavior of Acute Myeloid Leukemia Kasumi-1 Cells.
Hui-Li LIU ; Wen-Xin XU ; Yang-Yan CAI ; Hong-Mei LI
Journal of Experimental Hematology 2025;33(5):1312-1317
OBJECTIVE:
To investigate the role of nucleolin (NCL) in acute myeloid leukemia (AML) Kasumi-1 cells and its underlying mechanism.
METHODS:
The Kasumi-1 cells were infected with lentivirus carrying shRNA to downregulate NCL expression. Cell proliferation was detected by CCK-8 assay, and cell apoptosis and cell cycle were determined by flow cytometry. Transcriptome next-generation sequencing (NGS) was performed to predict associated signaling pathways, the expression levels of related genes were measured by RT-PCR.
RESULTS:
Down-regulation of NCL expression significantly inhibited the proliferation of Kasumi-1 cells (P <0.01) and markedly increased the apoptosis rate (P <0.001). Cell cycle analysis showed significant changes in the distribution of cells in the G1 and S phases after NCL knockdown (P <0.05), while no significant difference was observed in the G2 phase (P >0.05). Transcriptome sequencing analysis demonstrated that differentially expressed genes in Kasumi-1 cells with low expression of NCL were primarily enriched in key signaling pathways, including ribosome, spliceosome, RNA transport, cell cycle, and amino acid biosynthesis. qPCR validation showed that the expression of BAX, CASP3, CYCS, PMAIP1, TP53 , and CDKN1A was significantly upregulated after NCL downregulation (P <0.05), with CDKN1A exhibiting the most pronounced difference.
CONCLUSION
NCL plays a critical role in regulating the proliferation, apoptosis, and cell cycle progression of Kasumi-1 cells. The mechanism likely involves suppressing cell cycle progression through activation of the TP53-CDKN1A pathway and promoting apoptosis by upregulating apoptosis-related genes.
Humans
;
Leukemia, Myeloid, Acute/pathology*
;
Down-Regulation
;
Cell Proliferation
;
Apoptosis
;
RNA-Binding Proteins/genetics*
;
Nucleolin
;
Cell Line, Tumor
;
Phosphoproteins/metabolism*
;
Cell Cycle
;
Signal Transduction
;
RNA, Small Interfering
7.Tanshinone II A Facilitates Chemosensitivity of Osteosarcoma Cells to Cisplatin via Activation of p38 MAPK Pathway.
Da-Ming XIE ; Zhi-Yun LI ; Bing-Kai REN ; Rui GONG ; Dong YANG ; Sheng HUANG
Chinese journal of integrative medicine 2025;31(4):326-335
OBJECTIVE:
To examine the mechanism of action of tanshinone II A (Tan II A) in promoting chemosensitization of osteosarcoma cells to cisplatin (DDP).
METHODS:
The effects of different concentrations of Tan II A (0-80 µ mol/L) and DDP (0-2 µ mol/L) on the proliferation of osteosarcoma cell lines (U2R, U2OS, 143B, and HOS) at different times were examined using the cell counting kit-8 and colony formation assays. Migration and invasion of U2R and U2OS cells were detected after 24 h treatment with 30 µ mol/L Tan II A, 0.5 µ mol/L DDP alone, and a combination of 10 µ mol/L Tan II A and 0.25 µ mol/L DDP using the transwell assay. After 48 h of treatment of U2R and U2OS cells with predetermined concentrations of each group of drugs, the cell cycle was analyzed using a cell cycle detection kit and flow cytometry. After 48 h treatment, apoptosis of U2R and U2OS cells was detected using annexin V-FITC apoptosis detection kit and flow cytometry. U2R cells were inoculated into the unilateral axilla of nude mice and then the mice were randomly divided into 4 groups of 6 nude mice each. The 4 groups were treated with equal volume of Tan II A (15 mg/kg), DDP (3 mg/kg), Tan II A (7.5 mg/kg) + DDP (1.5 mg/kg), and normal saline, respectively. The body weight of the nude mice was weighed, and the tumor volume and weight were measured. Cell-related gene and signaling pathway expression were detected by RNA sequencing and Kyoto Encyclopedia of Genes and Genomes pathway analysis. p38 MAPK signaling pathway proteins and apoptotic protein expressions were detected by Western blot.
RESULTS:
In vitro studies have shown that Tan II A, DDP and the combination of Tan II A and DDP inhibit the proliferation, migration and invasion of osteosarcoma cells. The inhibitory effect was more pronounced in the Tan II A and DDP combined treatment group (P<0.05 or P<0.01). Osteosarcoma cells underwent significantly cell-cycle arrest and cell apoptosis by Tan II A-DDP combination treatment (P<0.05 or P<0.01). In vivo studies demonstrated that the Tan II A-DD combination treatment group significantly inhibited tumor growth compared to the Tan II A and DDP single drug group (P<0.01). Additionally, we found that the combination of Tan II A and DDP treatment enhanced the p38 MAPK signaling pathway. Western blot assays showed higher p-p38, cleaved caspase-3, and Bax and lower caspase-3, and Bcl-2 expressions with the combination of Tan II A and DDP treatment compared to the single drug treatment (P<0.01).
CONCLUSION
Tan II A synergizes with DDP by activating the p38/MAPK pathway to upregulate cleaved caspase-3 and Bax pro-apoptotic gene expressions, and downregulate caspase-3 and Bcl-2 inhibitory apoptotic gene expressions, thereby enhancing the chemosensitivity of osteosarcoma cells to DDP.
Abietanes/therapeutic use*
;
Osteosarcoma/enzymology*
;
Cisplatin/therapeutic use*
;
Humans
;
Cell Line, Tumor
;
Animals
;
Apoptosis/drug effects*
;
Mice, Nude
;
Cell Proliferation/drug effects*
;
Cell Movement/drug effects*
;
p38 Mitogen-Activated Protein Kinases/metabolism*
;
MAP Kinase Signaling System/drug effects*
;
Bone Neoplasms/enzymology*
;
Cell Cycle/drug effects*
;
Xenograft Model Antitumor Assays
;
Mice
;
Drug Resistance, Neoplasm/drug effects*
;
Neoplasm Invasiveness
;
Mice, Inbred BALB C
8.Hesperidin Suppressed Colorectal Cancer through Inhibition of Glycolysis.
Ke-Xiang SUN ; Wei-Shan TAN ; Hao-Yue WANG ; Jia-Min GAO ; Shu-Yun WANG ; Man-Li XIE ; Wan-Li DENG
Chinese journal of integrative medicine 2025;31(6):529-540
OBJECTIVE:
To explore the role of the natural compound hesperidin in glycolysis, the key ratelimiting enzyme, in colorectal cancer (CRC) cell lines.
METHODS:
In vitro, HCT116 and SW620 were treated with different doses of hesperidin (0-500 µmol/L), cell counting kit-8 and colone formation assays were utilized to detected inhibition effect of hesperidin on CRC cell lines. Transwell and wound healing assays were performed to detect the ability of hesperidin (0, 25, 50 and 75 µmol/L) to migrate CRC cells. To confirm the apoptotic-inducing effect of hesperidin, apoptosis and cycle assays were employed. Western blot, glucose uptake, and lactate production determination measurements were applied to determine inhibitory effects of hesperidin (0, 25 and 50 µmol/L) on glycolysis. In vivo, according to the random number table method, nude mice with successful tumor loading were randomly divided into vehicle, low-dose hesperidin (20 mg/kg) and high-dose hesperidin (60 mg/kg) groups, with 6 mice in each group. The body weights and tumor volumes of mice were recorded during 4-week treatment. The expression of key glycolysis rate-limiting enzymes was determined using Western blot, and glucose uptake and lactate production were assessed. Finally, protein interactions were probed with DirectDIA Quantitative Proteomics, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses.
RESULTS:
Hesperidin could inhibit CRC cell line growth (P<0.05 or P<0.01). Moreover, hesperidin presented an inhibitory effect on the migrating abilities of CRC cells. Hesperidin also promoted apoptosis and cell cycle alterations (P<0.05). The immunoblotting results manifested that hesperidin decreased the levels of hexokinase 2, glucose transporter protein 1 (GLUT1), GLUT3, L-lactate dehydrogenase A, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2), PFKFB3, and pyruvate kinase isozymes M2 (P<0.01). It remarkably suppressed tumor xenograft growth in nude mice. GO and KEGG analyses showed that hesperidin treatment altered metabolic function.
CONCLUSION
Hesperidin inhibits glycolysis and is a potential therapeutic choice for CRC treatment.
Hesperidin/therapeutic use*
;
Colorectal Neoplasms/metabolism*
;
Glycolysis/drug effects*
;
Animals
;
Humans
;
Apoptosis/drug effects*
;
Mice, Nude
;
Cell Movement/drug effects*
;
Cell Line, Tumor
;
Cell Proliferation/drug effects*
;
Glucose/metabolism*
;
Cell Cycle/drug effects*
;
Mice, Inbred BALB C
;
Mice
;
HCT116 Cells
;
Lactic Acid
9.Resveratrol Attenuates Inflammation in Acute Lung Injury through ROS-Triggered TXNIP/NLRP3 Pathway.
Wen-Han HUANG ; Kai-Ying FAN ; Yi-Ting SHENG ; Wan-Ru CAI
Chinese journal of integrative medicine 2025;31(12):1078-1086
OBJECTIVE:
To evaluate the protective effects of resveratrol against acute lung injury (ALI) and investigate the potential mechanisms underlying the reactive oxygen species (ROS)-triggered thioredoxin-interacting protein (TXNIP)/NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) pathway.
METHODS:
C57BL/6 mice and J774A.1 cells were selected as the research subjects. Thirty Mice were randomly divided into 5 groups of 6 in each group: control with 0.9% saline, 5 mg/kg lipopolysaccharide (LPS) 24 h, 25 mg/kg resveratrol + 5 mg/kg LPS, 100 mg/kg resveratrol + 5 mg/kg LPS, and 4 mg/kg NLRP3 inhibitor CY-09 + 5 mg/kg LPS. For cell stimulation, cells were pretreated with 5 and 20 µmol/L resveratrol for 2 h, and stimulated with or without 1 µg/mL LPS and 3 mmol/L ATP for 2 h. The antioxidant N-acetyl-L-cysteine (NAC, 2 µmol/L) was used as the positive control group. Hematoxylin and eosin staining was used to evaluate the degree of lung LPS-induced tissue damage, and enzyme-linked immunosorbent assay was used to evaluate the contents of interleukin-1 β (IL-1 β) and IL-18 in the serum and cell supernatant. ROS and malondialdehyde (MDA) levels in the lung tissue were detected using the corresponding kits. Western blotting was used to detect the expressions of TXNIP, high-mobility group box 1 (HMGB1), NLRP3, as well as cysteine-aspartic acid protease 1 (caspase-1) and gasdermin D (GSDMD) along with their cleaved forms in lung tissue. Additionally, reverse transcription quantitative polymerase chain reaction was performed to analyze the expression of related inflammatory cytokines. ROS content was detected using flow cytometry and confocal laser microscopy. Mitochondrial morphological changes were observed using transmission electron microscopy, and HMGB1 expression was detected using immunofluorescence.
RESULTS:
Resveratrol significantly alleviated LPS-induced lung damage with reduced inflammation, interstitial edema, and leukocyte infiltration (P<0.01). It also decreased serum levels of IL-1 β and IL-18 (P<0.05), while downregulating the expressions of NLRP3, IL-6, and other inflammatory markers at both the protein and mRNA levels (P<0.05). Notably, the higher dose (100 mg/kg) demonstrated a better effect than the lower dose (25 mg/kg). In macrophages, resveratrol reduced IL-1 β and IL-18 following LPS and ATP stimulation, suppressed HMGB1 translocation, and inhibited formation and activation of the NLRP3 inflammasome (P<0.05 or P<0.01). These anti-inflammatory effects were mediated through the suppression ROS accumulation (P<0.01) and mitochondrial dysfunction. Transmission electron microscopy revealed that resveratrol preserved mitochondrial structure, preventing the mitochondrial damage seen in LPS-treated groups (P<0.01). The expressions of cleaved caspase-1, cleaved GSDMD, and cytoplasmic HMGB1 were all reduced following resveratrol treatment (P<0.01). Moreover, resveratrol inhibited dissociation of TXNIP from thioredoxin, blocking subsequent activation of NLRP3 and downstream inflammatory cytokines (P<0.01). Similarly, the higher concentration of resveratrol (20 µ mol/L) exhibited superior efficacy in vitro.
CONCLUSION
Resveratrol can reduce the inflammatory response following ALI and inhibit the activation of NLRP3 inflammasome and the level of HMGB1 in the cytoplasm by inhibiting ROS overproduction.
Acute Lung Injury/metabolism*
;
NLR Family, Pyrin Domain-Containing 3 Protein/metabolism*
;
Animals
;
Resveratrol/pharmacology*
;
Reactive Oxygen Species/metabolism*
;
Inflammation/complications*
;
Mice, Inbred C57BL
;
Carrier Proteins/metabolism*
;
Signal Transduction/drug effects*
;
Lipopolysaccharides
;
Thioredoxins/metabolism*
;
Mice
;
Lung/drug effects*
;
Male
;
Cell Line
;
Interleukin-1beta/metabolism*
;
Cell Cycle Proteins
;
Stilbenes/therapeutic use*
10.Application and mechanisms of targeting BRD4 in osteosarcoma.
Ding CHEN ; Jiaming TIAN ; Yihe DONG ; Zi LI ; Jun HUANG
Journal of Central South University(Medical Sciences) 2025;50(3):416-429
OBJECTIVES:
Metastasis is the primary cause of death in osteosarcoma, and current clinical treatments remain limited. BRD4, a key epigenetic regulator, has shown therapeutic promise in various cancers through its inhibition. However, the mechanistic role of BRD4 in osteosarcoma remains poorly understood. This study aims to elucidate the molecular mechanisms by which BRD4 regulate osteosarcoma progression and to explore novel therapeutic strategies.
METHODS:
Immunofluorescence was used to assess BRD4 expression levels in a tissue microarray containing 80 osteosarcoma samples from different patients. The Gene Expression Omnibus (GEO) dataset (GSE42352, containing survival data from 88 osteosarcoma patients) was downloaded to perform Kaplan-Meier survival analysis based on BRD4 gene expression levels. In vivo, an orthotopic intramedullary osteosarcoma model was established using HOS cells in C57 mice, followed by treatment with varying doses of the BRD4 inhibitor (+)-JQ1. Micro-CT, 3D reconstruction of bone tissue, and HE staining were employed to evaluate pathological changes in bone and intestinal lymph nodes. In vitro, cell viability was measured using the methyl thiazolyl tetrazolium (MTT) assay, while colony formation and Transwell assays assessed proliferative and invasive capacities. Chromatin-bound BRD4 was analyzed via co-immunoprecipitation combined with mass spectrometry (Co-IP/MS), and O-GlcNAc glycosylation sites and glycan chains of BRD4 were identified using Co-IP with Nano-LC MS/MS. Real-time PCR and Western blotting were used to analyze the relative mRNA and protein expression levels of target genes, respectively.
RESULTS:
BRD4 was positively expressed in 61.25% (49/80) of osteosarcoma tissues. Patients with high BRD4 expression exhibited significantly shorter survival times (P<0.05). In the orthotopic mouse model, intervention with (+)-JQ1, a potent and commonly used BETi, significantly inhibited tumor growth in vivo and reduced bone destruction (P<0.05). (+)-JQ1 treatment significantly suppressed the proliferation (P<0.001), invasion (P<0.001), and migration (P<0.05) of HOS cells. In osteosarcoma cells, BRD4 exhibited O-GlcNAc modifications at both N- and C- C-termini, particularly at Thr73, which is essential for protein stability. This modification also contributed to the activation of the EGFR tyrosine kinase inhibitor resistance pathway (KEGG Pathway: hsa01521). (+)-JQ1 treatment displaced BRD4 from enhancers and downregulated the transcription of pathway-related genes, such as EGFR and PDGFC, thereby suppressing the malignant behavior of osteosarcoma cells.
CONCLUSIONS
BRD4 promotes osteosarcoma progression via O-GlcNAc modification at Thr73 and plays a crucial role in tumor growth and metastasis.
Osteosarcoma/drug therapy*
;
Humans
;
Transcription Factors/metabolism*
;
Animals
;
Cell Cycle Proteins
;
Mice
;
Bone Neoplasms/drug therapy*
;
Azepines/pharmacology*
;
Cell Line, Tumor
;
Cell Proliferation/drug effects*
;
Triazoles/pharmacology*
;
Mice, Inbred C57BL
;
Nuclear Proteins/metabolism*
;
Gene Expression Regulation, Neoplastic
;
Male
;
Bromodomain Containing Proteins

Result Analysis
Print
Save
E-mail