OBJECTIVE: To explore the mechanism of BNIP3-mediated mitophagy in m.3635G>A related Leber's hereditary optic neuropathy (LHON). METHODS: A trans-mitochondrial cybrid cell line derived from a Chinese LHON patient carrying the m.3635G>A, diagnosed at the Eye Hospital of Wenzhou Medical University in September 2013, was selected as the study subject. A trans-mitochondrial cybrid cell line from a healthy control with an identical mitochondrial background was included as a control. Immunofluorescence, real-time quantitative PCR (RT-qPCR), and Western blotting were employed to assess the expression of autophagy-related proteins, aiming to explore the role of BNIP3-mediated mitophagy in m.3635G>A related LHON. This study was approved by the Medical Ethics Committee of the Eye Hospital of Wenzhou Medical University (Ethics No. 2023-J-096). RESULTS: Compared with the control group, the protein expression levels of autophagy-related markers LC3 (LC3-II/LC3-I) and LAMP1 were significantly reduced in the variant group (P < 0.05). Additionally, the protein levels of macroautophagy-related proteins ATG12, ATG7, and ATG5 were also significantly decreased (P < 0.05). Compared with the control cells, the mRNA and protein expression levels of mitophagy-associated protein BNIP3 were significantly reduced in the cells of the variant group (P < 0.05). Compared with the control group, both mRNA and protein expression levels of the mitophagy-related protein BNIP3 were significantly reduced in the variant group (P < 0.05). CONCLUSION The m.3635G>A inhibits BNIP3-mediated mitophagy, thereby contributing to the pathogenesis of LHON.
Humans ; Proto-Oncogene Proteins/metabolism* ; Mitophagy/genetics* ; Membrane Proteins/metabolism* ; Optic Atrophy, Hereditary, Leber/metabolism* ; Mitochondria/metabolism* ; Cell Line ; Male

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a patient with De-differentiated liposarcoma (DDLPS). METHODS: A 38-year-old female patient with DDLPS who had visited Hunan Provincial People's Hospital in January 2025 was selected as the study subject. A retrospective study method was adopted to collect the patient's clinical data, including current and past medical history, auxiliary examinations, pathological diagnosis, and results of genetic testing. This study was approved by the Ethics Committee of Hunan Provincial People's Hospital (Ethics No.: KY2025-150). RESULTS: The patient had presented with abdominal pain and abdominal mass. Imaging studies revealed ascites and space-occupying abdominal lesions. Postoperative pathological examination showed that the tumor was composed of spindle cells, and its morphology and immunohistochemistry had made it difficult to distinguish between DDLPS and leiomyosarcoma. High-throughput sequencing revealed characteristic molecular alterations of DDLPS, and fluorescence in situ hybridization confirmed MDM2 gene amplification, leading to a diagnosis of DDLPS. CONCLUSION The patient was diagnosed with DDLPS. Her clinical manifestations and pathological features were consistent with the characteristics of DDLPS. Molecular pathological testing played a crucial role in the diagnosis and provided a crucial reference for subsequent treatment.
Humans ; Female ; Adult ; Liposarcoma/diagnosis* ; Phenotype ; Proto-Oncogene Proteins c-mdm2/genetics*

OBJECTIVE: To explore the clinical and genetic characteristics of a patient with Beck-Fahrner syndrome attributed to a TET3 gene variants. METHODS: A case of Beck-Fahrner syndrome (proband) who was treated at the Children's Hospital of Nanjing Medical University in December 2021 was selected as the study subject. Clinical data of the family were collected. Peripheral blood samples of the proband and his parents were collected, and genomic DNA was extracted for whole exome sequencing (WES). Candidate variants were verified in the family by Sanger sequencing. According to the "Classification Criteria and Guidelines for Genetic Variations" formulated by the American College of Medical Genetics and Genomics (hereinafter referred to as "ACMG guidelines"), the pathogenicity of the TET3 gene variant sites was rated. This study was approved by the Medical Ethics Committee of the Children's Hospital of Nanjing Medical University (Ethics No.: 202402022-1). RESULTS: The proband was a male, with a age of 9 months at the time of consultation. His clinical manifestations included decreased muscle tone, global developmental delay, long face, and open mouth. WES revealed that he has harbored a c.2811_c.2812insAGAC (p.T938fs*27) (NM_001287491) truncation variant in exon 7 of the TET3 gene. Sanger sequencing showed that neither of his parents has harbored the same variant. According to the ACMG guidelines, the variant was rated as pathogenic (PVS1+PS2+PM2_Supporting). CONCLUSION The TET3 gene c.2811_c.2812insAGAC variant probably underlay the pathogenesis of Beck-Fahrner syndrome in the proband. Above discovery has enriched the mutational spectrum of the TET3 gene and provided a reference for the diagnosis and treatment of this disease.
Humans ; Male ; Frameshift Mutation ; Infant ; Dioxygenases/genetics* ; Exome Sequencing ; Female ; Proto-Oncogene Proteins/genetics* ; Pedigree

OBJECTIVES: To investigate the mechanism mediating the regulatory effect of miR-155-5p on proliferation of human submandibular gland epithelial cells (HSGECs) in primary Sjogren's syndrome (pSS). METHODS: Dual luciferase reporter assay was used to verify the targeting relationship between miR-155-5p and the PI3K/AKT pathway. In a HSGEC model of pSS induced by simulation with TRAIL and INF-γ, the effects of miR-155-inhibitor-NC or miR-155 inhibitor on cell viability, cell cycle, apoptosis and proliferation were evaluated using CKK8 assay, flow cytometry and colony formation assay. ELISA and RT-PCR were used to detect the expressions of inflammatory cytokines and miR-155-5p mRNA in the cells; Western blotting was performed to detect the expressions of proteins in the PI3K/AKT signaling pathway. RESULTS: Dual luciferase assay showed that miR-155-5p targets the PI3K/AKT pathway via PIK3R1 mRNA. The HSGEC model of pSS showed significantly decreased cell viability, cell clone formation ability and expressions IL-10 and IL-4 and increased cell apoptosis, cell percentage in G2 phase, expressions of TNF‑α, IL-6, miR-155-5p and PIK3R1 mRNA, p-PI3K/PI3K ratio, p-Akt/AKT ratio, and PIK3R1 protein expression. Treatment of the cell models with miR-155 inhibitor significantly increased the cell viability, G1 phase cell percentage, colony formation ability, and expressions of IL-10 and IL-4 levels, and obviously reduced cell apoptosis rate, G2 phase cell percentage, expressions of TNF-α, IL-6, miR-155-5p and PIK3R1 mRNA, p-PI3K/PI3K ratio, p-AKT/AKT ratio, and PIK3R1 protein expression. CONCLUSIONS In HSGEC model of pSS, inhibition of miR-155-5p can promote cell proliferation and reduced cell apoptosis by targeting PI3K1 mRNA to negatively regulate the overexpression of PI3K/AKT signaling pathway.
Humans ; MicroRNAs/genetics* ; Cell Proliferation ; Signal Transduction ; Proto-Oncogene Proteins c-akt/metabolism* ; Sjogren's Syndrome/pathology* ; Epithelial Cells/cytology* ; Submandibular Gland/cytology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Apoptosis ; Class Ia Phosphatidylinositol 3-Kinase ; Cells, Cultured

OBJECTIVES: To investigate the effect of downregulation of medium-chain acyl-coenzyme A dehydrogenase (ACADM) on invasion and migration of estrogen receptor-positive breast cancer cells and the underlying mechanism. METHODS: The Kaplan-Meier Plotter database was used to analyze the ACADM expression levels in breast cancer and normal tissues and their association with patient prognosis. Human breast cancer MCF-7 and T47D cell lines with lentivirus-mediated ACADM knockdown were established, and their in situ tumor formation and metastasis after tail vein injection were evaluated in nude mice. The MCF-7 and T47D cells with ACADM knockdown and their unmodified parental cells were examined with oil-red O staining assay, ROS assay, mitochondrial respiratory chain function assay before and after treatments with ROS scavenger, Elamipretide (a cardiolipin oxidation inhibitor) or SC79 (an AKT activator), and the changes in migration and invasion abilities of the treated cells were analyzed with Transwell invasion assay and Boyden chamber assay. Western blotting was used to detect protein expression levels of related signaling pathways in the treated cells. RESULTS: ACADM overexpression was associated with a significantly shorter overall survival of breast cancer patients. In MCF-7 and T47D cells, ACADM knockdown resulted in downregulation of N calnexin, vimentin, p-P13K and p-AKT proteins, increased levels of free fatty acids and reactive oxygen species, lowered activities of mitochondrial respiratory chain complex III and V, and reduced mitochondrial inner phospholipids. ACADM knockdown significantly decreased the invasive capacity of the cells, which were obviously reversed by treatment with ROS scavenger, Elamipretide, and SC79. CONCLUSIONS Down-regulation of ACADM inhibits migration and invasion ability of estrogen receptor-positive breast cancer cells by lowering lipotoxicity and impairing mitochondrial function through the ROS/PI3K/AKT pathway.
Humans ; Breast Neoplasms/metabolism* ; Female ; Mice, Nude ; Down-Regulation ; Neoplasm Invasiveness ; Animals ; Mice ; Receptors, Estrogen/metabolism* ; MCF-7 Cells ; Cell Movement ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Acyl-CoA Dehydrogenase/genetics* ; Signal Transduction ; Neoplasm Metastasis ; Proto-Oncogene Proteins c-akt/metabolism*

OBJECTIVES: To evaluate the protective effect of Lycium barbarum polysaccharides (LBP) against cisplatin-induced ovarian granulosa cell injury and investigate its possible mechanisms. METHODS: Human granulosa-like tumor cell line (KGN) were treated with 2.5 µg/mL cisplatin for 24 h, followed by treatment with 100, 500, and 1000 mg/L LBP, and the changes in cell viability, apoptosis, level of anti-Müllerian hormone (AMH), and cell ultrastructure were detected with CCK-8 assay, flow cytometry, ELISA and transmission electron microscopy. The cellular expressions of Bax, caspase-3, Bcl-2, and the PI3K/AKT pathway proteins were analyzed using Western blotting, and the expression of miR-23a was detected with RT-qPCR. KGN cell models with lentivirus-mediated miR-23a overexpression or knockdown were used to verify the therapeutic mechanism of LBP. RESULTS: Cisplatin treatment significantly inhibited cell viability, induced apoptosis, decreased AMH level, caused ultrastructural abnormalities, increased Bax and caspase-3 expression, and lowered Bcl-2 expression in KGN cells. Cisplatin also suppressed the activation of the PI3K/AKT signaling pathway and upregulated miR-23a expression in the cells. LBP intervention obviously alleviated cisplatin-induced injuries in KGN cells, and in particular, LBP treatment at the medium dose for 24 h significantly improved KGN cell viability, reduced apoptosis, enhanced their endocrine function, and ameliorated ultrastructural abnormalities. Mechanistically, medium-dose LBP obviously activated the PI3K/AKT pathway by downregulating miR-23a in cisplatin-treated cells, subsequently inhibiting Bax and caspase-3 while upregulating Bcl-2. Overexpression of miR-23a weakened while knockdown of miR-23a significantly enhanced the protective effects of LBP. CONCLUSIONS LBP alleviates cisplatin-induced apoptosis in KGN cells by inhibiting miR-23a expression and activating the PI3K/AKT pathway, suggesting a potential therapeutic strategy for ovarian function preservation.
Humans ; Cisplatin/adverse effects* ; MicroRNAs/genetics* ; Female ; Granulosa Cells/cytology* ; Apoptosis/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Down-Regulation ; Signal Transduction/drug effects* ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Cell Line, Tumor ; Cell Survival/drug effects*

The angiogenic response is essential for the repair of ischemic brain tissue. Integrin α6 (Itga6) expression has been shown to increase under hypoxic conditions and is expressed exclusively in vascular structures; however, its role in post-ischemic angiogenesis remains poorly understood. In this study, we demonstrate that mice with endothelial cell-specific knockout of Itga6 exhibit reduced neovascularization, reduced pericyte coverage on microvessels, and accelerated breakdown of microvascular integrity in the peri-infarct area. In vitro, endothelial cells with ITGA6 knockdown display reduced proliferation, migration, and tube-formation. Mechanistically, we demonstrated that ITGA6 regulates post-stroke angiogenesis through the PI3K/Akt-eNOS-VEGFA axis. Importantly, the specific overexpression of Itga6 in endothelial cells significantly enhanced neovascularization and enhanced the integrity of microvessels, leading to improved functional recovery. Our results suggest that endothelial cell Itga6 plays a crucial role in key steps of post-stroke angiogenesis, and may represent a promising therapeutic target for promoting recovery after stroke.
Animals ; Nitric Oxide Synthase Type III/metabolism* ; Mice ; Proto-Oncogene Proteins c-akt/metabolism* ; Integrin alpha6/genetics* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Stroke/pathology* ; Vascular Remodeling/physiology* ; Vascular Endothelial Growth Factor A/metabolism* ; Mice, Knockout ; Signal Transduction/physiology* ; Mice, Inbred C57BL ; Male ; Neovascularization, Physiologic/physiology*

Hypoxia and aberrant activation of epidermal growth factor receptor (EGFR) are considered important features of various malignancies. However, whether hypoxia can directly trigger EGFR activation and its clinical implications remain unclear. In this study, we demonstrated that in oral cancer, a typical hypoxic tumor, hypoxia can induce chronic but constitutive phosphorylation of wild-type EGFR in the absence of ligands. Oral cancer cell lines exhibit different EGFR phosphorylation responses to hypoxia. In hypoxic HN4 and HN6 cells, ubiquitination-mediated endocytosis, lysosomal sorting, and degradation lead to low levels of EGFR phosphorylation. However, in CAL-27 and HN30 cells, a novel HIF-1α-induced long noncoding RNA (lncRNA), EUDAL, can compete with the E3 ligase/adaptor complex c-Cbl/Grb2 for binding to EGFR, stabilizing phosphorylated EGFR (pEGFR) and resulting in sustained activation of EGFR and its downstream STAT3/BNIP3 signaling. STAT3/BNIP3-mediated autophagy leads to antitumor drug resistance. A high EUDAL/EGFR/STAT3/autophagy pathway activation predicts poor response to chemotherapy in oral cancer patients. Collectively, hypoxia can induce noncanonical ligand-independent EGFR phosphorylation. High EUDAL expression facilitates sustained EGFR phosphorylation in hypoxic tumor cells and leads to autophagy-related drug resistance.
Humans ; ErbB Receptors/metabolism* ; Mouth Neoplasms/pathology* ; RNA, Long Noncoding/genetics* ; Drug Resistance, Neoplasm/genetics* ; Cell Line, Tumor ; Phosphorylation ; Signal Transduction ; STAT3 Transcription Factor/metabolism* ; Cell Hypoxia ; Autophagy ; Proto-Oncogene Proteins c-cbl/metabolism*

Glutamine provides carbon and nitrogen to support the proliferation of cancer cells. However, the precise reason why cancer cells are particularly dependent on glutamine remains unclear. In this study, we report that glutamine modulates the tumor suppressor F-box and WD repeat domain-containing 7 (FBW7) to promote cancer cell proliferation and survival. Specifically, lysine 604 (K604) in the sixth of the 7 substrate-recruiting WD repeats of FBW7 undergoes glutaminylation (Gln-K604) by glutaminyl tRNA synthetase. Gln-K604 inhibits SCFFBW7-mediated degradation of c-Myc and Mcl-1, enhances glutamine utilization, and stimulates nucleotide and DNA biosynthesis through the activation of c-Myc. Additionally, Gln-K604 promotes resistance to apoptosis by activating Mcl-1. In contrast, SIRT1 deglutaminylates Gln-K604, thereby reversing its effects. Cancer cells lacking Gln-K604 exhibit overexpression of c-Myc and Mcl-1 and display resistance to chemotherapy-induced apoptosis. Silencing both c-MYC and MCL-1 in these cells sensitizes them to chemotherapy. These findings indicate that the glutamine-mediated signal via Gln-K604 is a key driver of cancer progression and suggest potential strategies for targeted cancer therapies based on varying Gln-K604 status.
Glutamine/metabolism* ; Myeloid Cell Leukemia Sequence 1 Protein/genetics* ; Humans ; Proto-Oncogene Proteins c-myc/genetics* ; Cell Proliferation ; Signal Transduction ; Neoplasms/pathology* ; F-Box-WD Repeat-Containing Protein 7/genetics* ; Cell Survival ; Cell Line, Tumor ; Apoptosis

Psoriasis is a chronic inflammatory skin disease, and its pathogenesis is largely modulated by abnormal angiogenesis. Previous research has indicated that AlkB homolog 5 (ALKBH5), an important demethylase affecting N⁶-methyladenosine (m⁶A) modification, plays a role in regulating angiogenesis in cardiovascular and eye diseases. Our present study found that ALKBH5 was upregulated and co-localized with cluster of differentiation 31 (CD31) in the skin of IMQ group compared with control group. ALKBH5-deficient mice decreased IMQ-induced psoriatic dermatitis and exhibited histological improvements, including decreased epidermal thickness, hyperkeratosis, numbers of dermal capillary vessels and inflammatory cell infiltration. ALKBH5-KO mice alleviated angiogenesis in psoriatic lesions by downregulating the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway. Additionally, the expression of ALKBH5 was significantly upregulated in IL-17A-induced human umbilical vein endothelial cells (HUVECs), which further promoted the expression of angiogenesis-related cytokines and endothelial cell proliferation. Cell proliferation and angiogenesis were suppressed in ALKBH5 knockdown group, whereas ALKBH5 overexpression promoted these processes. The regulation of angiogenesis in HUVECs by ALKBH5 was facilitated through the AKT-mTOR pathway. Collectively, ALKBH5 plays a pivotal role in psoriatic dermatitis and angiogenesis, which may offer a new potential targets for treating psoriasis.
Animals ; Psoriasis/chemically induced* ; Mice ; Humans ; Neovascularization, Pathologic/genetics* ; Human Umbilical Vein Endothelial Cells/metabolism* ; AlkB Homolog 5, RNA Demethylase/genetics* ; Proto-Oncogene Proteins c-akt/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Cell Proliferation ; Mice, Knockout ; Disease Models, Animal ; Signal Transduction ; Male ; Skin/blood supply* ; Mice, Inbred C57BL ; Angiogenesis