1.P4HA1 mediates YAP hydroxylation and accelerates collagen synthesis in temozolomide-resistant glioblastoma.
Xueru LI ; Gangfeng YU ; Xiao ZHONG ; Jiacheng ZHONG ; Xiangyu CHEN ; Qinglong CHEN ; Jinjiang XUE ; Xi YANG ; Xinchun ZHANG ; Yao LING ; Yun XIU ; Yaqi DENG ; Hongda LI ; Wei MO ; Yong ZHU ; Ting ZHANG ; Liangjun QIAO ; Song CHEN ; Fanghui LU
Chinese Medical Journal 2025;138(16):1991-2005
BACKGROUND:
Temozolomide (TMZ) resistance is a significant challenge in treating glioblastoma (GBM). Collagen remodeling has been shown to be a critical factor for therapy resistance in other cancers. This study aimed to investigate the mechanism of TMZ chemoresistance by GBM cells reprogramming collagens.
METHODS:
Key extracellular matrix components, including collagens, were examined in paired primary and recurrent GBM samples as well as in TMZ-treated spontaneous and grafted GBM murine models. Human GBM cell lines (U251, TS667) and mouse primary GBM cells were used for in vitro studies. RNA-sequencing analysis, chromatin immunoprecipitation, immunoprecipitation-mass spectrometry, and co-immunoprecipitation assays were conducted to explore the mechanisms involved in collagen accumulation. A series of in vitro and in vivo experiments were designed to assess the role of the collagen regulators prolyl 4-hydroxylase subunit alpha 1 (P4HA1) and yes-associated protein (YAP) in sensitizing GBM cells to TMZ.
RESULTS:
This study revealed that TMZ exposure significantly elevated collagen type I (COL I) expression in both GBM patients and murine models. Collagen accumulation sustained GBM cell survival under TMZ-induced stress, contributing to enhanced TMZ resistance. Mechanistically, P4HA1 directly binded to and hydroxylated YAP, preventing ubiquitination-mediated YAP degradation. Stabilized YAP robustly drove collagen type I alpha 1 ( COL1A1) transcription, leading to increased collagen deposition. Disruption of the P4HA1-YAP axis effectively reduced COL I deposition, sensitized GBM cells to TMZ, and significantly improved mouse survival.
CONCLUSION
P4HA1 maintained YAP-mediated COL1A1 transcription, leading to collagen accumulation and promoting chemoresistance in GBM.
Temozolomide
;
Humans
;
Glioblastoma/drug therapy*
;
Animals
;
Mice
;
Cell Line, Tumor
;
Drug Resistance, Neoplasm/genetics*
;
YAP-Signaling Proteins
;
Hydroxylation
;
Dacarbazine/pharmacology*
;
Adaptor Proteins, Signal Transducing/metabolism*
;
Transcription Factors/metabolism*
;
Collagen/biosynthesis*
;
Collagen Type I/metabolism*
;
Prolyl Hydroxylases/metabolism*
;
Antineoplastic Agents, Alkylating/therapeutic use*
2.Buyang Huanwu Decoction targets PPARG/SPP1/CD44 signaling pathway: mechanisms of lipid dysregulation and treatment in idiopathic pulmonary fibrosis.
Gang-Gang LI ; Xiao-Chuan PAN ; Fei WANG ; Quan-Yu DU
China Journal of Chinese Materia Medica 2025;50(14):3821-3834
Idiopathic pulmonary fibrosis(IPF) is a chronic progressive interstitial lung disease characterized by a complex pathogenesis and limited treatment options. Although studies have indicated that lipid metabolism dysregulation is associated with the progression of IPF, the core regulatory mechanisms remain unclear. By integrating RNA sequencing data from the GEO database, we identified four key genes related to lipid metabolism: peroxisome proliferator-activated receptor gamma(PPARG), secreted phosphoprotein 1(SPP1), caspase 3(CASP3), and platelet endothelial cell adhesion molecule 1(PECAM1). Further validation using single-cell RNA sequencing revealed the cell-specific expression patterns of these genes. The results found that PPARG was significantly downregulated in alveolar macrophages while SPP1 was significantly upregulated. Mechanistic studies indicated that PPARG negatively regulated SPP1 expression, and the interaction between SPP1 and cluster of differentiation 44(CD44) activated intercellular signaling pathways that promoted fibrosis. Through network pharmacology and molecular docking, it was predicted that the bioactive components of the traditional Chinese medicine formula, namely Buyang Huanwu Decoction may target PPARG to modulate lipid metabolism pathways. In a bleomycin-induced rat model with IPF, this paper randomly divided the rats into six groups(control, group, model group, pirfenidone group, and low, middle, and high-dose groups of Buyang Huanwu Decoction). The results demonstrated that Buyang Huanwu Decoction treatment significantly improved tissue pathological damage, reduced collagen deposition, and alleviated lipid metabolism dysregulation. Western blot analysis confirmed that Buyang Huanwu Decoction mediated the upregulation of PPARG and inhibited the activation of the SPP1/CD44 pathway. The multi-omics study elucidated the role of the PPARG/SPP1/CD44 pathway as a key regulatory factor in lipid metabolism in IPF, providing evidence that Buyang Huanwu Decoction exerted its antifibrotic effects through this novel mechanism and thus offering new insights into the therapeutic prospects for IPF.
Animals
;
Drugs, Chinese Herbal/administration & dosage*
;
Signal Transduction/drug effects*
;
PPAR gamma/genetics*
;
Humans
;
Osteopontin/genetics*
;
Lipid Metabolism/drug effects*
;
Idiopathic Pulmonary Fibrosis/genetics*
;
Hyaluronan Receptors/genetics*
;
Rats
;
Male
;
Rats, Sprague-Dawley
;
Molecular Docking Simulation
3.Diterpenoids and lignans from fossil Chinese medicinal succinum and their activity against renal fibrosis.
Yefei CHEN ; Yunfei WANG ; Yunyun LIU ; Yongming YAN ; Yongxian CHENG
Chinese Journal of Natural Medicines (English Ed.) 2025;23(7):888-896
Five previously undescribed diterpenoids, named succipenoids D‒H (1‒5), along with four undescribed lignans, named succignans A‒D (6‒9), were isolated from the dichloromethane extract of Chinese medicinal succinum. Compounds 1‒5 were characterized as nor-abietane diterpenoids, while compounds 6‒9 were identified as lignans polymerized from two groups of phenylpropanoid units. The structures of these novel compounds, including their absolute configurations, were determined through spectroscopic and computational methods. Biological assessments of renal fibrosis demonstrated that compounds 6 and 7 effectively reduce the expression of proteins associated with renal fibrosis, including α-smooth muscle actin (α-SMA), collagen I, and fibronectin in transforming growth factor-β1 (TGF-β1) induced normal rat kidney proximal tubular epithelial cells (NRK-52e).
Animals
;
Rats
;
Lignans/isolation & purification*
;
Diterpenes/isolation & purification*
;
Fibrosis/drug therapy*
;
Drugs, Chinese Herbal/pharmacology*
;
Molecular Structure
;
Cell Line
;
Kidney Diseases/pathology*
;
Transforming Growth Factor beta1/genetics*
;
Kidney/metabolism*
;
Actins/genetics*
;
Fibronectins/genetics*
;
Collagen Type I/genetics*
;
Epithelial Cells/metabolism*
4.Bioactive glass 45S5 promotes odontogenic differentiation of apical papilla cells through autophagy.
Weilin LIU ; Can SU ; Caiyun CUI
West China Journal of Stomatology 2025;43(1):37-45
OBJECTIVES:
The mechanism of the odontogenic differentiation of apical papillary cells (APCs) stimulated by bioactive glass 45S5 is still unclear. This study aims to investigate the effect of autophagy on the odontogenic differentiation of APCs stimulated by bioactive glass 45S5.
METHODS:
APCs were isolated and cultured <i>in vitroi>, and the cell origin was identified by flow cytometry. The culture medium was prepared with 1 mg/mL 45S5, and its pH and ion concentration were determined. The experiments were divided into control, 45S5, and 3-methyladenine (3-MA) 45S5 groups. In the 45S5 group, APCs were induced to culture with 1 mg/mL 45S5. In the 3-MA 45S5 group, the autophagy inhibitor 3-MA was added to 1 mg/mL 45S5. Protein immunoblotting assay (Western blot) was used to detect the expression of autophagy-associated proteins of microtubule-associated protein 1 light-chain 3β (LC3B) and P62 after 24 h of induction culture in each group. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of bone sialoprotein (BSP), Runt-related transcription factor 2 (Runx2), dentin sialophosphoprotein (DSPP), and dentin matrix protein-1 (DMP-1) after 7 d of induction culture. Cellular alkaline phosphatase (ALP) staining analyzed cellular ALP activity at 7 d of induction, and alizarin red staining evaluated the formation of mineralized nodules at 21 d of induction.
RESULTS:
The pH of the 45S5 extract culture medium was 8.65±0.01, which was not significantly different from that of the control group (<i>Pi>>0.05). The silicon ion concentration of the 45S5 induction culture medium was (1.56±0.07) mmol/L, which was higher than that of the control group (0.08±0.01) mmol/L (<i>Pi><0.05). The calcium ion concentration of the 45S5 induction culture was (1.57±0.15) mmol/L, which was not significantly different from that of the control group (<i>Pi>>0.05). Western blot results showed that LC3B-Ⅱ/Ⅰ ratio increased and P62 expression decreased in the 45S5 group compared with those in the control group (<i>Pi><0.05). By contrast, the ratio decreased and the expression increased in the 3-MA 45S5 group compared with those in the 45S5 group (<i>Pi><0.05). RT-qPCR results showed that the expression of BSP, Runx2, DMP-1, and DSPP enhanced in the 45S5 group compared with that in the control group (<i>Pi><0.05), but the expression decreased in the 3-MA 45S5 group compared with that in the 45S5 group (<i>Pi><0.05). Semi-quantitative analysis of ALP staining and alizarin red staining showed that the ALP activity was enhanced, and the formation mineralized nodule increased in the 45S5 group compared with those in the control group. The ALP activity weakened, and the formation mineralized nodules were reduced in the 3-MA 45S5 group compared with that those in the 45S5 group.
CONCLUSIONS
Cell autophagy participates in the odontogenic differentiation of APCs induced by 1 mg/mL 45S5 <i>in vitroi>.
Autophagy/drug effects*
;
Cell Differentiation/drug effects*
;
Odontogenesis/drug effects*
;
Dental Papilla/cytology*
;
Humans
;
Microtubule-Associated Proteins/metabolism*
;
Glass/chemistry*
;
Cells, Cultured
;
Core Binding Factor Alpha 1 Subunit/metabolism*
;
Extracellular Matrix Proteins/metabolism*
;
Ceramics/pharmacology*
;
Adenine/pharmacology*
;
Sialoglycoproteins/metabolism*
;
Phosphoproteins/metabolism*
;
Integrin-Binding Sialoprotein/metabolism*
;
Alkaline Phosphatase/metabolism*
;
RNA-Binding Proteins
5.Effects of Gly mutations N-terminal to the integrin-binding sequence on the structure and function of recombinant collagen.
Fei LI ; Yuxi HOU ; Ben RAO ; Xiaoyan LIU ; Yaping WANG ; Yimin QIU
Chinese Journal of Biotechnology 2025;41(4):1573-1587
Collagen, a vital matrix protein for various tissue and functions in animals, is widely applied in biomaterials. In type Ⅰ collagen, missense mutations of glycine (Gly) in the Gly-Xaa-Yaa triplet of the triple helix are a major cause of osteogenesis imperfecta (OI). Clinical manifestations exhibit marked heterogeneity, spanning a broad disease spectrum from mild skeletal fragility (Type Ⅰ) to severe limb deformities (Type Ⅲ) and perinatal lethal forms (Type Ⅱ). This study utilized recombinant collagen as a model to further elucidate whether Gly→Ala/Val mutations at the N-terminus of the integrin-binding sequence GFPGER affect collagen structure and function, and to explore the underlying mechanisms by which missense mutations impact the biological function of collagen. By introducing Ala and Val substitutions at seven Gly positions N-terminal to the GFPGER sequence, we systematically assessed the effects of these amino acid replacements on the triple-helical structure, thermal stability, integrin-binding ability, and cell adhesion of recombinant collagen. All constructs formed a stable triple-helix structure, with slightly compromised thermal stability. Gly→Val substitutions increased the susceptibility of recombinant collagen to trypsin, which suggested local conformational perturbations in the triple helix. In addition, Gly→Val substitutions significantly reduced the integrin-binding affinity and decreased HT1080 cell adhesion, with the effects stronger than Gly→Ala substitutions. Compared with Gly→Ala substitutions, substitution of Gly with the larger residue Val had enhanced negative effects on the structure and function of recombinant collagen. These findings provide new insights into the molecular mechanisms of osteogenesis imperfecta and offer theoretical references and experimental foundations for the design of collagen sequences and the development of collagen-based biomaterials.
Recombinant Proteins/biosynthesis*
;
Glycine/genetics*
;
Humans
;
Osteogenesis Imperfecta/genetics*
;
Integrins/metabolism*
;
Collagen/metabolism*
;
Collagen Type I/metabolism*
;
Amino Acid Substitution
;
Mutation
;
Mutation, Missense
6.Research on the mechanism of gentiopicroside preventing macrophage-mediated liver fibrosis by regulating the MIF-SPP1 signaling pathway in hepatic stellate cells.
Jixu WANG ; Yingbin ZHU ; Maoli CHEN ; Yongfeng HAN
Chinese Journal of Cellular and Molecular Immunology 2025;41(7):593-602
Objective To explore the mechanism by which gentiopicroside (GPS) prevents macrophage-mediated hepatic fibrosis by regulating the macrophage migration inhibitory factor (MIF)-secreted phosphoprotein 1 (SPP1) signaling pathway in hepatic stellate cells. Methods LX-2 cells were divided into control group, transforming growth factor β(TGF-β) group, and TGF-β combined with GPS (25, 50, 100, 150 μmol/mL) groups. Cell proliferation was detected by EDU assay, cell invasion was assessed by TranswellTM assay, and the protein expressions of α-smooth muscle actin (α-SMA) and type I collagen (COL1A1) were measured by Western blot. M1-type macrophage-conditioned medium (M1-CM) was used to treat LX-2 cells in the TGF-β group and TGF-β combined with GPS group. The concentrations of inducible nitric oxide synthase (iNOS) and arginase 1 (Arg1) in the cell supernatant, as well as cell proliferation, invasion ability, and the expressions of α-SMA and COL1A1 were detected. Bioinformatics analysis was performed to identify the target intersections of GPS, hepatic fibrosis, and macrophage-related genes. Drug affinity responsive target stability (DARTS) experiments and Western blot were used to verify the regulatory effect of GPS on MIF. Furthermore, LX-2 cells were divided into control group, TGF-β group, TGF-β combined with M2-CM group, TGF-β and oe-NC combined with M2-CM group, and TGF-β and oe-MIF combined with M2-CM group to analyze the concentrations of iNOS and Arg1 in the cell supernatant, as well as changes in cell proliferation, invasion, and the expressions of α-SMA and COL1A1. LX-2 cells were also divided into control group, TGF-β group, TGF-β combined with oe-NC group, TGF-β combined with oe-MIF group, and TGF-β and oe-MIF combined with GPS group to determine the protein expressions of MIF and SPP1 by Western blot. A rat model of hepatic fibrosis was constructed to explore the potential therapeutic effects of GPS on hepatic fibrosis in vivo. Results Compared with the control group, the proliferation and invasion abilities of LX-2 cells in the TGF-β group were increased, and the protein expressions of α-SMA and COL1A1 were enhanced. GPS intervention inhibited the proliferation and invasion of LX-2 cells under TGF-β conditions and reduced the expressions of α-SMA and COL1A1. Compared with the control group, the concentration of iNOS in the cell supernatant of the TGF-β group was upregulated, while the concentration of Arg1 was decreased. M1-CM treatment further increased the concentration of iNOS, decreased the concentration of Arg1, and promoted cell proliferation and invasion, as well as upregulated the expressions of α-SMA and COL1A1 on the basis of TGF-β intervention. However, GPS could reverse the effects of M1-CM intervention. Bioinformatics analysis revealed that MIF was one of the target intersections of GPS, hepatic fibrosis, and macrophage-related genes, and GPS could target and inhibit its expression. Compared with the TGF-β group, after M2-CM intervention, the concentration of iNOS in the cell supernatant decreased, the concentration of Arg1 increased, the proliferation and invasion abilities of LX-2 cells were reduced, and the expressions of α-SMA and COL1A1 were weakened. However, overexpression of MIF reversed the effects of M2-CM intervention. Western blot results showed that compared with the control group, the protein expressions of MIF and SPP1 were enhanced in the TGF-β group. Overexpression of MIF further enhanced the expressions of MIF and SPP1, while GPS intervention inhibited the expressions of MIF and SPP1. In the animal experiment, GPS intervention treatment alleviated liver injury in rats with hepatic fibrosis and inhibited the expressions of MIF and SPP1, as well as α-SMA and COL1A1 in liver tissue. Conclusion GPS may prevent macrophage-mediated hepatic fibrosis by inhibiting the MIF-SPP1 signaling pathway in hepatic stellate cells.
Hepatic Stellate Cells/metabolism*
;
Signal Transduction/drug effects*
;
Macrophage Migration-Inhibitory Factors/genetics*
;
Liver Cirrhosis/prevention & control*
;
Macrophages/drug effects*
;
Iridoid Glucosides/pharmacology*
;
Humans
;
Cell Proliferation/drug effects*
;
Animals
;
Cell Line
;
Collagen Type I/metabolism*
;
Collagen Type I, alpha 1 Chain
;
Intramolecular Oxidoreductases/genetics*
;
Rats
;
Transforming Growth Factor beta/pharmacology*
;
Actins/metabolism*
7.Changes in circulating levels of calcium and bone metabolism biochemical markers in patients receiving denosumab treatment.
Yuancheng CHEN ; Wen WU ; Ling XU ; Haiou DENG ; Ruixue WANG ; Qianwen HUANG ; Liping XUAN ; Xueying CHEN ; Ximei ZHI
Journal of Southern Medical University 2025;45(4):760-764
OBJECTIVES:
To investigate the changes in blood levels of calcium and bone metabolism biochemical markers in patients with primary osteoporosis receiving treatment with denosumab.
METHODS:
Seventy-three patients with primary osteoporosis treated in our Department between December, 2021 and December 2023 were enrolled. All the patients were treated with calcium supplements, vitamin D and calcitriol in addition to regular denosumab treatment every 6 months. Blood calcium, parathyroid hormone (PTH), osteocalcin (OC), type I procollagen amino-terminal propeptide (PINP), and type I collagen carboxy-terminal telopeptide β special sequence (β‑CTX) data before and at 3, 6, 9, and 12 months after the first treatment were collected from each patient.
RESULTS:
Three months after the first denosumab treatment, the bone turnover markers (BTMs) OC, PINP, and β-CTX were significantly decreased compared to their baseline levels by 39.5% (<i>Pi><0.001), 56.2% (<i>Pi><0.001), and 81.8% (<i>Pi><0.001), respectively. At 6, 9, and 12 months of treatment, OC, PINP, and β-CTX remained significantly lower than their baseline levels (<i>Pi><0.001). Blood calcium level was decreased (<i>Pi><0.05) and PTH level increased (<i>Pi><0.05) significantly in these patients at months of denosumab treatment, but their levels were comparable to the baseline levels at 6, 9, and 12 months of the treatment (<i>Pi>>0.05).
CONCLUSIONS
Denosumab can suppress BTMs and has a good therapeutic effect in patients with primary osteoporosis, but reduction of blood calcium and elevation of PTH levels can occur during the first 3 months in spite of calcium supplementation. Blood calcium and PTH levels can recover the baseline levels as the treatment extended, suggesting the importance of monitoring blood calcium and PTH levels during denosumab treatment.
Humans
;
Denosumab/therapeutic use*
;
Calcium/blood*
;
Parathyroid Hormone/blood*
;
Biomarkers/blood*
;
Osteoporosis/blood*
;
Osteocalcin/blood*
;
Procollagen/blood*
;
Female
;
Collagen Type I/blood*
;
Peptide Fragments/blood*
;
Bone Density Conservation Agents/therapeutic use*
;
Bone and Bones/metabolism*
;
Male
;
Middle Aged
;
Vitamin D
;
Peptides/blood*
;
Aged
8.Abnormal collagen deposition mediated by cartilage oligomeric matrix protein in the pathogenesis of oral submucous fibrosis.
Yafei XIONG ; Xuechun LI ; Bincan SUN ; Jie ZHANG ; Xiaoshan WU ; Feng GUO
International Journal of Oral Science 2025;17(1):25-25
Abnormal accumulation of collagen fibrils is a hallmark feature of oral submucous fibrosis (OSF). However, the precise characteristics and underlying mechanisms remain unclear, impeding the advancement of potential therapeutic approaches. Here, we observed that collagen I, the main component of the extracellular matrix, first accumulated in the lamina propria and subsequently in the submucosa of OSF specimens as the disease progressed. Using RNA-seq and Immunofluorescence in OSF specimens, we screened the cartilage oligomeric matrix protein (COMP) responsible for the abnormal collagen accumulation. Genetic COMP deficiency reduced arecoline-stimulated collagen I deposition significantly in vivo. In comparison, both COMP and collagen I were upregulated under arecoline stimulation in wild-type mice. Human oral buccal mucosal fibroblasts (hBMFs) also exhibited increased secretion of COMP and collagen I after stimulation in vitro. COMP knockdown in hBMFs downregulates arecoline-stimulated collagen I secretion. We further demonstrated that hBMFs present heterogeneous responses to arecoline stimulation, of which COMP-positive fibroblasts secrete more collagen I. Since COMP is a molecular bridge with Fibril-associated collagens with Interrupted Triple helices (FACIT) in the collagen network, we further screened and identified collagen XIV, a FACIT member, co-localizing with both COMP and collagen I. Collagen XIV expression increased under arecoline stimulation in wild-type mice, whereas it was hardly expressed in the Comp-/- mice, even with under stimulation. In summary, we found that COMP may mediates abnormal collagen I deposition by functions with collagen XIV during the progression of OSF, suggesting its potential to be targeted in treating OSF.
Oral Submucous Fibrosis/pathology*
;
Cartilage Oligomeric Matrix Protein/genetics*
;
Animals
;
Mice
;
Humans
;
Fibroblasts/metabolism*
;
Collagen Type I/metabolism*
;
Arecoline/pharmacology*
;
Mouth Mucosa/metabolism*
;
Cells, Cultured
;
Fluorescent Antibody Technique
9.Expert consensus on peri-implant keratinized mucosa augmentation at second-stage surgery.
Shiwen ZHANG ; Rui SHENG ; Zhen FAN ; Fang WANG ; Ping DI ; Junyu SHI ; Duohong ZOU ; Dehua LI ; Yufeng ZHANG ; Zhuofan CHEN ; Guoli YANG ; Wei GENG ; Lin WANG ; Jian ZHANG ; Yuanding HUANG ; Baohong ZHAO ; Chunbo TANG ; Dong WU ; Shulan XU ; Cheng YANG ; Yongbin MOU ; Jiacai HE ; Xingmei YANG ; Zhen TAN ; Xiaoxiao CAI ; Jiang CHEN ; Hongchang LAI ; Zuolin WANG ; Quan YUAN
International Journal of Oral Science 2025;17(1):51-51
Peri-implant keratinized mucosa (PIKM) augmentation refers to surgical procedures aimed at increasing the width of PIKM. Consensus reports emphasize the necessity of maintaining a minimum width of PIKM to ensure long-term peri-implant health. Currently, several surgical techniques have been validated for their effectiveness in increasing PIKM. However, the selection and application of PIKM augmentation methods may present challenges for dental practitioners due to heterogeneity in surgical techniques, variations in clinical scenarios, and anatomical differences. Therefore, clear guidelines and considerations for PIKM augmentation are needed. This expert consensus focuses on the commonly employed surgical techniques for PIKM augmentation and the factors influencing their selection at second-stage surgery. It aims to establish a standardized framework for assessing, planning, and executing PIKM augmentation procedures, with the goal of offering evidence-based guidance to enhance the predictability and success of PIKM augmentation.
Humans
;
Consensus
;
Dental Implants
;
Mouth Mucosa/surgery*
;
Keratins
10.Clinical and genetic analysis of two children with Knobloch syndrome due to variants of COL18A1 gene.
Xuyuan GAO ; Yongping TANG ; Zailong CHI
Chinese Journal of Medical Genetics 2025;42(11):1308-1315
OBJECTIVE:
To explore the clinical phenotype and genetic characteristics in two children with Knobloch syndrome (KNO) due to variants of COL18A1 gene.
METHODS:
Two children presented at the Genetic Eye Disease Clinic of the Eye Hospital of Wenzhou Medical University in October 2023 for ocular lesions were selected as the study subjects. Relevant clinical data and peripheral venous blood samples were collected from the children and their parents. Following genomic DNA extraction, whole-exome sequencing (WES) was carried out. Candidate variants were verified by Sanger sequencing of the family members. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2021-212-K-185).
RESULTS:
Both children exhibited characteristic ocular features of KNO including nystagmus, high myopia, and leopard spot fundus. Additionally, child 1 also presented with congenital occipital bone dysplasia and occipital encephalocele, while child 2 was diagnosed with vitreoretinochoroidopathy and bilateral high myopia. WES has identified compound heterozygous variants of the COL18A1 gene in both children, including a c.3013+3A>C splice-site variant and a c.2743C>T (p.Arg915Ter) nonsense variant in child 1, and a novel c.1702-1G>A splice-site variant and a c.3836C>T (p.Ser1279Leu) missense variant in child 2. A comprehensive literature review has identified 63 domestic and international articles involving 167 patients with KNO whom can be classified into three subtypes, with KNO type I being the most common and caused by pathogenic variants in the COL18A1 gene. Both probands in this study were children with KNO type I. Analysis of the genotype-phenotype correlations and population distribution characteristics revealed that the KNO patients exhibited significant clinical and genetic heterogeneity, along with a broad geographic distribution, with a relatively greater number of cases reported in Brazil and China. and a broad geographic distribution, with the highest numbers reported in Brazil and China. While no significant difference in genotype distribution was observed between Chinese and non-Chinese patients, phenotypic disparities were noted, with the non-Chinese cohort showing significantly higher rates of retinal detachment and developmental delay (P < 0.05), whereas Chinese patients exhibited a greater proportion of macular hypoplasia (P < 0.05).
CONCLUSION
The main clinical manifestations of KNO include high myopia, vitreoretinal dystrophy, and occipital encephalocele. The novel c.1702-1G>A splice-site variant identified in the COL18A1 gene has expanded the mutational spectrum of KNO type I and provided valuable insights for genetic diagnosis, counseling, and clinical management of the disease.
Humans
;
Retinal Detachment/congenital*
;
Male
;
Female
;
Child
;
Encephalocele/genetics*
;
Exome Sequencing
;
Collagen Type XVIII/genetics*
;
Phenotype
;
Retinal Degeneration/genetics*
;
Mutation
;
Child, Preschool

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